Heterotopic ossification of the elbow after closed reduction and retrograde intramedullary nailing for radial neck fracture treated by anconeus interposition.

PubMed

Sreenivas, T; Menon, Jagdish; Nataraj, A R

2013-12-01

Heterotopic ossification around the elbow can lead to considerable functional disability. We describe a case of a 42-year-old man who developed heterotopic ossification of his elbow after closed reduction of the elbow dislocation and radial neck fracture and retrograde intramedullary nailing for radial neck fracture. During the follow-up after initial surgery, movements of the elbow were gradually deteriorated and diagnosed as heterotopic ossification of the elbow. Implant removal, radial head excision along with heterotopic mass, and also interposition of the anconeus muscle resulted in improvement of his elbow mobility. At 18 months of follow-up, patient had elbow flexion arc of 15°-110°, 70° of supination, and 50° of pronation without recurrence of heterotopic ossification. The uniqueness of this case lies in the treatment of heterotopic ossification of the elbow to prevent its recurrence, which was developed after retrograde intramedullary nailing for radial neck fracture following closed reduction.

Variation Among Pediatric Orthopaedic Surgeons When Treating Medial Epicondyle Fractures.

PubMed

Hughes, Meghan; Dua, Karan; O'Hara, Nathan N; Brighton, Brian K; Ganley, Theodore J; Hennrikus, William L; Herman, Martin J; Hyman, Joshua E; Lawrence, J Todd; Mehlman, Charles T; Noonan, Kenneth J; Otsuka, Norman Y; Schwend, Richard M; Shrader, M Wade; Smith, Brian G; Sponseller, Paul D; Abzug, Joshua M

2017-10-18

Medial epicondyle fractures are a common pediatric and adolescent injury accounting for 11% to 20% of elbow fractures in this population. This purpose of this study was to determine the variability among pediatric orthopaedic surgeons when treating pediatric medial epicondyle fractures. A discrete choice experiment was conducted to determine which patient and injury attributes influence the management of medial epicondyle fractures by pediatric orthopaedic surgeons. A convenience sample of 13 pediatric orthopaedic surgeons reviewed 60 case vignettes of medial epicondyle fractures that included elbow radiographs and patient/injury characteristics. Displacement was incorporated into the study model as a fixed effect. Surgeons were queried if they would treat the injury with immobilization alone or open reduction and internal fixation (ORIF). Statistical analysis was performed using a mixed effect regression model. In addition, surgeons filled out a demographic questionnaire and a risk assessment to determine if these factors affected clinical decision-making. Elbow dislocation and fracture displacement were the only attributes that significantly influenced surgeons to perform surgery (P<0.05). The presence of an elbow dislocation had the largest impact on surgeons when choosing operative care (β=-0.14; P=0.02). In addition, for every 1 mm increase in displacement, surgeons tended to favor ORIF by a factor of 0.09 (P<0.01). Sex, mechanism of injury, and sport participation did not influence decision-making. In total, 54% of the surgeons demonstrated a preference for ORIF for the included scenarios. On the basis of the personality Likert scale, participants were neither high-risk takers nor extremely risk adverse with an average-risk score of 2.24. Participant demographics did not influence decision-making. There is substantial variation among pediatric orthopaedic surgeons when treating medial epicondyle fractures. The decision to operate is significantly based on the degree of fracture displacement and if there is a concomitant elbow dislocation. There is no standardization regarding how to treat medial epicondyle fractures and better treatment algorithms are needed to provide better patient outcomes. Level V.

Milch versus Stimson technique for nonsedated reduction of anterior shoulder dislocation: a prospective randomized trial and analysis of factors affecting success.

PubMed

Amar, Eyal; Maman, Eran; Khashan, Morsi; Kauffman, Ehud; Rath, Ehud; Chechik, Ofir

2012-11-01

The shoulder is regarded as the most commonly dislocated major joint in the human body. Most dislocations can be reduced by simple methods in the emergency department, whereas others require more complicated approaches. We compared the efficacy, safety, pain, and duration of the reduction between the Milch technique and the Stimson technique in treating dislocations. We also identified factors that affected success rate. All enrolled patients were randomized to either the Milch technique or the Stimson technique for dislocated shoulder reduction. The study cohort consisted of 60 patients (mean age, 43.9 years; age range, 18-88 years) who were randomly assigned to treatment by either the Stimson technique (n = 25) or the Milch technique (n = 35). Oral analgesics were available for both groups. The 2 groups were similar in demographics, patient characteristics, and pain levels. The first reduction attempt in the Milch and Stimson groups was successful in 82.8% and 28% of cases, respectively (P < .001), and the mean reduction time was 4.68 and 8.84 minutes, respectively (P = .007). The success rate was found to be affected by the reduction technique, the interval between dislocation occurrence and first reduction attempt, and the pain level on admittance. The success rate and time to achieve reduction without sedation were superior for the Milch technique compared with the Stimson technique. Early implementation of reduction measures and low pain levels at presentation favor successful reduction, which--in combination with oral pain medication--constitutes an acceptable and reasonable management alternative to reduction with sedation. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Evaluation of outcome of corrective ulnar osteotomy with bone grafting and annular ligament reconstruction in neglected monteggia fracture dislocation in children.

PubMed

Datta, Tanmay; Chatterjee, Nd; Pal, Ananda Kisor; Das, Sunil Kumar

2014-06-01

Neglected Monteggia fracture dislocation in the paediatric age group constitutes significant disability in respect to pain, stiffness, deformity, neurological compromise and restriction of activities of daily living. A longitudinal prospective study was done on 21 children with old Monteggia fracture-dislocation which included 18 cases of Bado type I and 3 cases of Bado type III at the department of orthopaedics, IPGME&R,SSKM hospital, Kolkata, India between 2007 and 2012. All were treated by modified Hirayama corrective osteotomy of ulna with wedge bone grafting along with restoration of its length and reconstruction of annular ligament using Bell Tawse method and fixation of radial head with transcapitellar Kirschner wire. Average follow up period was 5.5 years. Results were evaluated on the basis of 100 point Mayo Elbow Performance Index, radiology and questionnaire. The mean postoperative increase in Mayo Elbow Performance Index score was 30 with average increase in the range of movement by 30o. In three cases, there was subluxation of radial head and in addition one had transient palsy of posterior interosseous nerve. Three cases showed distortion of the radial head which were insignificant functionally. Results of improvement in mean MEPI were analysed by chi-square test and was significant at 0 .01 level of significance. Study showed good results with modified Hirayama osteotomy with annular ligament reconstruction using Bell Tawse procedure which is a more biological option for restoration of elbow biomechanics.

Spontaneous displacement of olecranon fracture through geode salvaged by elbow replacement.

PubMed

Jaiswal, Anuj; Thakur, Raman; Relwani, Jaikumar; Ogufere, Wallace

2010-04-01

We present a case of pathological fracture of olecranon through a giant geode. Fracture was initially undisplaced and was treated conservatively. It later progressed to a transolecranon dislocation as a result of a pseudarthrosis at the fracture site. The patient presented 4 years later when she developed symptoms of ulnar nerve palsy. She was treated by a total elbow arthroplasty with ulnar nerve transposition. The current report highlights this unusual case and reviews the relevant literature.

[Efficient imaging of elbow injuries in children and adolescents].

PubMed

Kraus, R; Berthold, L D; von Laer, L

2007-01-01

The purpose of imaging of the elbow region in children after acute trauma is the diagnosis of injuries that require further treatment. Basic diagnostic consists of standard X-rays of the elbow in two planes. Exceptions can be made in the case of nursemaid's elbow lesion (subluxation of the radial head; pronation douloureuse; Chassaignac lesion) with unambiguous mechanism of the trauma where no X-ray imaging is needed and in heavily dislocated fractures for which one plane can be sufficient. X-ray imaging of the uninjured side is obsolete. Follow-up X-ray imaging is only allowed if consequences for the further treatment are expected. Ultrasound may partially replace X-rays in the future if further standardization of this technique can be achieved. MRI provides additional information in acute trauma which, however, remains currently without consequences for the further treatment strategy.

Episodic snapping of the medial head of the triceps due to weightlifting.

PubMed

Spinner, R J; Wenger, D E; Barry, C J; Goldner, R D

1999-01-01

We describe two patients who had episodic elbow snapping and ulnar nerve dysesthesias only after weightlifting. These symptoms would disappear soon afterward. The episodic nature of their complaints and findings led to misdiagnosis. We documented by repeated clinical examinations and magnetic resonance imaging that the presence of these symptoms correlated directly with the finding of intermittent, activity-related snapping of the medial triceps. In both patients, the symptoms disappeared when the medial portion of the triceps migrated medially but did not dislocate over the medial epicondyle with elbow flexion. Thus, a minor change in the configuration of the medial portion of the triceps (fluid accumulation) in the same individual at different times can cause intermittent dislocation of the medial triceps. Previous papers dealing with patients with snapping of the medial triceps describe symptoms exacerbated by athletic activities, but the constant finding of snapping on sequential examinations.

Modified Boytchev procedure for treatment of recurrent anterior dislocation of shoulder

PubMed Central

Garg, Anant Kumar; Ayan, Saankritya; Keshari, Vikas; Kundu, Debi; Mukhopadhyay, Kiran Kumar; Acharyya, Biplab

2011-01-01

Background: More than 200 different operations have been described for the treatment of recurrent anterior dislocation of shoulder. The Modified Boytchev procedure employs rerouting of the detached tip of coracoid process with its attached conjoined tendon (short head of biceps and coracobrachialis) deep to subscapularis and reattaches to its anatomical location. We conducted a study on evaluation of long-term effect of modified Boytchev procedure and to compare our results with other studies published in literature. Materials and Methods: Since June 2002, modified Boytchev procedure was performed on 48 patients, who presented with recurrent anterior dislocation. 45 were men and 3 were women and were in the age group of 18-40 years (mean 27.83±4.95 years). Forty patients were affected on the dominant side and rest on the non-dominant side. The mean number of dislocations in these patients was 18.22±12.08. The mean followup period was 58.13±19.06 months (range 18-96 months). The patients were evaluated by visual analogue score, modified American Shoulder and Elbow Surgeon's Score (ASES), and Single Assessment Numeric Evaluation (SANE) score at the last followup. Results: All the patients regained almost preoperative range of forward flexion at the last followup. In the preoperative period the mean external rotation deficit at 0° and at 90° of abduction was 13.22°±5.16° and 18.06°±6.50°, respectively. At the last followup, the mean external rotation deficit at 0° and at 90° of abduction was 8.06°±2.47° and 8.95°±2.07°, respectively. This improvement in external rotation deficit was statistically significant (P<.05). Preoperative scores were compared with the most recent followup scores for all variables with use of a paired t test. All patients had significant improvement in visual analogue score, modified American Shoulder and Elbow Surgeon's Score (ASES), and Single Assessment Numeric Evaluation (SANE) score at the last followup. Four of the patients developed superficial infection which got resolved after treating with antibiotics, and two of the patients developed transient musculocutaneous nerve paresis. There was no radiological evidence of loosening and migration of coracoid screw or any glenohumeral arthritis on subsequent followup of skiagrams in any of our patients. Conclusion: Modified Boytchev procedure is an efficacious and technically simple procedure to treat recurrent anterior dislocation of shoulder. PMID:21772627

In-game Management of Common Joint Dislocations

PubMed Central

Skelley, Nathan W.; McCormick, Jeremy J.; Smith, Matthew V.

2014-01-01

Context: Sideline management of sports-related joint dislocations often places the treating medical professional in a challenging position. These injuries frequently require prompt evaluation, diagnosis, reduction, and postreduction management before they can be evaluated at a medical facility. Our objective is to review the mechanism, evaluation, reduction, and postreduction management of sports-related dislocations to the shoulder, elbow, finger, knee, patella, and ankle joints. Evidence Acquisition: A literature review was performed using the PubMed database to evaluate previous and current publications focused on joint dislocations. This review focused on articles published between 1980 and 2013. Study Design: Clinical review. Level of Evidence: Level 4. Results: The clinician should weigh the benefits and risks of on-field reduction based on their knowledge of the injury and the presence of associated injuries. Conclusion: When properly evaluated and diagnosed, most sports-related dislocations can be reduced and initially managed at the game. PMID:24790695

ELBOW AND WRIST INJURIES IN SPORTS

PubMed Central

Marmor, Leonard; Bechtol, Charles O.

1960-01-01

Any disabling injury of the elbow or wrist should be studied roentgenographically for evidence of fracture which may not be otherwise evident but which may cause permanent disability unless the joint is immobilized for healing. “Tennis elbow” may be treated with physical therapy and analgesic injection but may require splinting or tendon stripping. Elbow sprain can occur in the growing epiphysis but is rare in adults. A jarring fall on the hand may cause fracture or dislocation at the elbow. Full extension of the joint should be restored gradually by active exercise rather than passive or forcible stretching. Fracture at the head of the radius may cause joint hemorrhage with severe pain which can be relieved by aspiration. A displacing fracture at the head of the radius requires removal of the head to prevent arthritic changes. Myositis ossificans contraindicates operation until after it has cleared. Healing of wrist fractures may be facilitated by exercise of the shoulder and elbow while the wrist is still in a cast. Fractures of the navicular bone are difficult to detect even roentgenographically and splinting may have to be done on clinical evidence alone. PMID:14421374

Loss of reduction and complications of coracoclavicular ligament reconstruction with autogenous tendon graft in acute acromioclavicular dislocations.

PubMed

Choi, Nam Hong; Lim, Seok Min; Lee, Sang Young; Lim, Tae Kang

2017-04-01

This study was conducted to report loss of reduction and complications after single-tunnel coracoclavicular (CC) ligament reconstruction with autogenous semitendinosus tendon graft for acute acromioclavicular (AC) joint dislocations. This retrospective study included patients with acute, unstable AC dislocations (surgery within 6 weeks after trauma). We excluded patients with chronic injury and distal clavicle fractures with CC ligaments disruption. We measured the CC distance on anteroposterior radiographs of both clavicles, preoperatively, immediately postoperatively, and at the final follow-up visit. We evaluated clinical outcomes using the American Shoulder and Elbow Surgeons Shoulder Assessment and the University of California, Los Angeles Shoulder Rating Scale scores and perioperative complications. There were 30 patients (27 men and 3 women) with mean age of 41 years (range, 19-70 years). The mean follow-up period was 31 months (range, 12-186 months). Mean CC distance was 15.5 ± 3.7 mm (84% ± 14% of the contralateral shoulder) preoperatively, 8.9 ± 2.6 mm (9% ± 40%) immediately postoperatively (P < .001), and 10.6 ± 3.3 mm (24% ± 39%) at the final assessment (P < .001), showing an increase of the CC distance during the follow-up. Loss of reduction (defined as >25% increase of CC distance) developed in 14 patients (47%), and complications occurred in 6 patients (20%), including 3 distal clavicle fractures through the tunnel. Final clinical scores were significantly lower in patients with complications (27 vs. 33 of the University of California, Los Angeles assessment [P < .001] and 81 vs. 95 of the American Shoulder and Elbow Surgeons Shoulder assessment [P < .001]). In acute AC joint dislocation, single-tunnel CC ligament reconstruction using autogenous tendon graft resulted in loss of reduction rate of 47% and a complication rate of 20%. The development of complications adversely affected clinical outcomes. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Open segmental fracture of both bone forearm and dislocation of ipsilateral elbow with extruded middle segment radius

PubMed Central

Kumar, Pawan; Manjhi, Lal Bahadur; Rajak, Ramesh Lal

2013-01-01

Extruded middle segment of radius with open segmental fracture both bone forearm and dislocation of ipsilateral elbow is a rare injury. A 12-year-old child presented to us within 4 hours following fall from tree. The child's mother was carrying a 12-cm-long extruded soiled segment of radius. The extruded bone was thoroughly washed. The medullary cavity was properly syringed with antiseptic solution. The bone was autoclaved and put in the muscle plane of the distal forearm after debridement of the wound. After 5 days, a 2.5-mm K-wire was introduced by retrograde method into the proximal radius by passing through the extruded segment. Another 2.5-mm K-wire was passed in ulna. The limb was evaluated clinicoradiologically every 2 weeks. The wound was healed by primary intention. At 4 months, the reposed bone appeared less dense radiologically and K-wire seemed to be out of the bone. In the subsequent months, the roentgenograms show remodeling of the extruded fragment. After 20 weeks, the K-wires were removed (first ulnar and then radial). Complete union was achieved with full range of movement except loss of few degrees of extension of elbow and thumb. This case is reported to show a good outcome following successful incorporation of an extruded segment of radius in an open fracture. PMID:23798764

Surgical treatment of acute type V acromioclavicular joint dislocations in professional athletes: an anatomic ligament reconstruction with synthetic implant augmentation.

PubMed

Triantafyllopoulos, Ioannis K; Lampropoulou-Adamidou, Kalliopi; Schizas, Nikitas P; Karadimas, Eleftherios V

2017-12-01

Most acromioclavicular (AC) joint injuries occur in men in their third decade of life during high-speed or high-impact body contact sports. The management of acute complete AC joint dislocation is surgical. Current surgical techniques include anatomic reconstruction of the main restraints of the AC joint and aim to improve functional outcomes and to reduce the complication rate. We present 10 cases of acute type V AC joint dislocation in professional athletes treated surgically with anatomic reconstruction of the coracoclavicular and AC ligaments and augmentation with the use of a synthetic polyester tape. The minimum follow-up of the patients was 2 years (mean, 48 months; range, 24-86 months). The postoperative functional outcome was assessed at 1 year and 2 years using the Constant-Murley, American Shoulder and Elbow Surgeons, and modified University of California-Los Angeles scoring systems. In all cases, the postoperative scores were significantly improved (P < .005 in all comparisons with the preoperative scores), and all patients returned to their preinjury high level of activity 6 months postoperatively. Radiographs at 1 month and 6 months revealed the maintenance of reduction. There were no complications. According to the results of our series of patients, demanding cases of acute AC joint dislocation Rockwood type V, in professional athletes, require anatomic fixation of both coracoclavicular and AC ligaments for return to sports as soon as possible and at the preinjury level of performance. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Neglected Monteggia fracture dislocations in children: a systematic review.

PubMed

Goyal, Tarun; Arora, Shobha S; Banerjee, Sumit; Kandwal, Pankaj

2015-05-01

Monteggia fractures are uncommon and frequently missed injuries in children. This article aims to study, in a systematic manner, the surgical management and complications of treatment of chronic radial head dislocations. After screening of relevant abstracts, a total of 28 studies were included in the systematic review. A narrative synthesis of various treatment modalities has been discussed. This article concludes that open reduction should be attempted unless dysmorphism of the radial head restricts it. Open reduction with ulnar osteotomy with or without annular ligament reconstruction is the most commonly performed procedure and is expected to result in reduced pain and elbow deformity.

Biceps Tendon Lengthening Surgery for Failed Serial Casting Patients With Elbow Flexion Contractures Following Brachial Plexus Birth Injury.

PubMed

Nath, Rahul K; Somasundaram, Chandra

2016-01-01

Assessment of surgical outcomes of biceps tendon lengthening (BTL) surgery in obstetric brachial plexus injury (OBPI) patients with elbow flexion contractures, who had unsuccessful serial casting. Serial casting and splinting have been shown to be effective in correcting elbow flexion contractures in OBPI. However, the possibilities of radial head dislocations and other complications have been reported in serial casting and splinting. Literature indicates surgical intervention when such nonoperative techniques and range-of-motion exercises fail. Here, we demonstrated a significant reduction of the contractures of the affected elbow and improvement in arm length to more normal after BTL in these patients, who had unsuccessful serial casting. Ten OBPI patients (6 girls and 4 boys) with an average age of 11.2 years (4-17.7 years) had BTL surgery after unsuccessful serial casting. Mean elbow flexion contracture was 40° before and 37° (average) after serial casting. Mean elbow flexion contracture was reduced to 8° (0°-20°) post-BTL surgical procedure with an average follow-up of 11 months. This was 75% improvement and statistically significant (P < .001) when compared to 7% insignificant (P = .08) improvement after serial casting. These OBPI patients in our study had 75% significant reduction in elbow flexion contractures and achieved an improved and more normal length of the affected arm after the BTL surgery when compared to only 7% insignificant reduction and no improvement in arm length after serial casting.

Radial nerve injury following elbow external fixator: report of three cases and literature review.

PubMed

Trigo, Luis; Sarasquete, Juan; Noguera, Laura; Proubasta, Ignacio; Lamas, Claudia

2017-07-01

Radial nerve palsy is a rare but serious complication following elbow external fixation. Only 11 cases have been reported in the literature to date, but the incidence may be underreported. We present three new cases of this complication. We analyzed the three cases of radial palsy seen in our center following the application of an external fixator as treatment for complex elbow injuries. Mean patient age at surgery was 50 years. Two patients were female and one was male. In the three cases, the initial lesion was a posterior elbow dislocation, associated with a fracture of the radial shaft in one and a radial head fracture and coronoid fracture, respectively, in the other two. Due to persistent elbow instability, an external fixator was applied in all three cases. The fixator pins were introduced percutaneously in two cases and under direct vision in an open manner in the third case. Radial palsy was noted immediately postoperatively in all cases. It was permanent in two cases and temporary in the third. Radial nerve palsy after placement of an external elbow fixator was resolved in only 1 of our 3 cases and in 6 of the 11 cases in the literature to date. Although the event is rare, these alarming results highlight the need for recommendations to avoid this complication.

Biceps Tendon Lengthening Surgery for Failed Serial Casting Patients With Elbow Flexion Contractures Following Brachial Plexus Birth Injury

PubMed Central

Somasundaram, Chandra

2016-01-01

Objective: Assessment of surgical outcomes of biceps tendon lengthening (BTL) surgery in obstetric brachial plexus injury (OBPI) patients with elbow flexion contractures, who had unsuccessful serial casting. Background: Serial casting and splinting have been shown to be effective in correcting elbow flexion contractures in OBPI. However, the possibilities of radial head dislocations and other complications have been reported in serial casting and splinting. Literature indicates surgical intervention when such nonoperative techniques and range-of-motion exercises fail. Here, we demonstrated a significant reduction of the contractures of the affected elbow and improvement in arm length to more normal after BTL in these patients, who had unsuccessful serial casting. Methods and Patients: Ten OBPI patients (6 girls and 4 boys) with an average age of 11.2 years (4-17.7 years) had BTL surgery after unsuccessful serial casting. Results: Mean elbow flexion contracture was 40° before and 37° (average) after serial casting. Mean elbow flexion contracture was reduced to 8° (0°-20°) post-BTL surgical procedure with an average follow-up of 11 months. This was 75% improvement and statistically significant (P < .001) when compared to 7% insignificant (P = .08) improvement after serial casting. Conclusion: These OBPI patients in our study had 75% significant reduction in elbow flexion contractures and achieved an improved and more normal length of the affected arm after the BTL surgery when compared to only 7% insignificant reduction and no improvement in arm length after serial casting. PMID:27648115

Formation, Migration, and Reactivity of Au CO Complexes on Gold Surfaces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Jun; McEntee, Monica; Tang, Wenjie

2016-01-12

Here, we report experimental as well as theoretical evidence that suggests Au CO complex formation upon the exposure of CO to active sites (step edges and threading dislocations) on a Au(111) surface. Room-temperature scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy, transmission infrared spectroscopy, and density functional theory calculations point to Au CO complex formation and migration. Room-temperature STM of the Au(111) surface at CO pressures in the range from 10^ 8 to 10^ 4 Torr (dosage up to 10^6 langmuir) indicates Au atom extraction from dislocation sites of the herringbone reconstruction, mobile Au CO complex formation and diffusion, and Aumore » adatom cluster formation on both elbows and step edges on the Au surface. The formation and mobility of the Au CO complex result from the reduced Au Au bonding at elbows and step edges leading to stronger Au CO bonding and to the formation of a more positively charged CO (CO +) on Au. These studies indicate that the mobile Au CO complex is involved in the Au nanoparticle formation and reactivity, and that the positive charge on CO increases due to the stronger adsorption of CO at Au sites with lower coordination numbers.« less

Modified technique for correction of isolated radial head dislocation without apparent ulnar bowing: a retrospective case study

PubMed Central

Tan, Lei; Li, Yan-Hui; Sun, Da-Hui; Zhu, Dong; Ning, Shu-Yan

2015-01-01

Objective: There is currently no general consensus on the optimal treatment of chronic radial head dislocation. Material and Methods: Considering that the annular ligament is important in maintaining elbow stability, we developed a modified method for annular ligament reconstruction in pediatric cases of radial head dislocation without ulnar bowing. We retrospectively investigated the therapeutic outcomes of this technique in a series of cases. We used our modified technique for the treatment of five patients between January 2006 and January 2012. The average age of the patients at the time of injury was 9 years (range, 6-14 years), and the patients were followed up for 1 to 3 years. Results: The perioperative and follow-up data of the patients were examined. All five surgical procedures were completed uneventfully and had been tolerated well by the patients, with minimal complications. Remarkable improvement was noted in all the cases at the end of the follow-up period. Conclusions: Our modified technique for annular ligament reconstruction was effective in achieving good reduction of the radial head dislocation with minimal complications in pediatric cases of isolated radial head dislocation without apparent ulnar bowing. PMID:26770420

Incidence of and risk factors for traumatic anterior shoulder dislocation: an epidemiologic study in high-school rugby players.

PubMed

Kawasaki, Takayuki; Ota, Chihiro; Urayama, Shingo; Maki, Nobukazu; Nagayama, Masataka; Kaketa, Takefumi; Takazawa, Yuji; Kaneko, Kazuo

2014-11-01

The incidence of reinjuries due to glenohumeral instability and the major risk factors for primary anterior shoulder dislocation in youth rugby players have been unclear. The purpose of this study was to investigate the incidence, mechanisms, and intrinsic risk factors of shoulder dislocation in elite high-school rugby union teams during the 2012 season. A total of 378 male rugby players from 7 high-school teams were investigated by use of self-administered preseason and postseason questionnaires. The prevalence of a history of shoulder dislocation was 14.8%, and there were 21 events of primary shoulder dislocation of the 74 overall shoulder injuries that were sustained during the season (3.2 events per 1000 player-hours of match exposure). During the season, 54.3% of the shoulders with at least one episode of shoulder dislocation had reinjury. This study also indicated that the persistence of glenohumeral instability might affect the player's self-assessed condition, regardless of the incidence during the current season. By a multivariate logistic regression method, a history of shoulder dislocation on the opposite side before the season was found to be a risk factor for contralateral primary shoulder dislocation (odds ratio, 3.56; 95% confidence interval, 1.27-9.97; P = .02). High-school rugby players with a history of shoulder dislocation are not playing at full capacity and also have a significant rate of reinjury as well as a high risk of dislocating the other shoulder. These findings may be helpful in deciding on the proper treatment of primary anterior shoulder dislocation in young rugby players. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

The prevalence of the complications and their associated factors in humeral lengthening for achondroplasia: retrospective study of 54 cases.

PubMed

Nakano-Matsuoka, Natsuko; Fukiage, Kenichi; Harada, Yuki; Kashiwagi, Naoya; Futami, Tohru

2017-11-01

The aim of this study is to evaluate the complications of humeral lengthening and their associated factors. Fifty-four achondroplastic patients were treated by bilateral humeral lengthening. Our original shoulder sling was sufficient to prevent shoulder dislocation. Pre-existing radial head dislocation was observed in 18 patients. Lengthening was accomplished in all cases without a decrease in the elbow function. Seven humeri fractured after the fixator removal. The risk factors for postoperative fracture were a waiting period of less than 5 days, a healing index less than 25, and the concave shape of the callus. There was no radial nerve palsy.

Appearance of wavefront dislocations under interference among beams with simple wavefronts

NASA Astrophysics Data System (ADS)

Angelsky, Oleg V.; Besaha, R. N.; Mokhun, Igor I.

1997-12-01

The appearance of wave front dislocations under interference among beams with simple wave fronts is considered. It is shown, that even two beams with the smooth wave fonts is possible the formation of dislocations screw type. The screw dislocations are formed in cross point of lines of equal amplitude of beams and minimum of an interference pattern.

Congenital joint dislocations caused by carbohydrate sulfotransferase 3 deficiency in recessive Larsen syndrome and humero-spinal dysostosis.

PubMed

Hermanns, Pia; Unger, Sheila; Rossi, Antonio; Perez-Aytes, Antonio; Cortina, Hector; Bonafé, Luisa; Boccone, Loredana; Setzu, Valeria; Dutoit, Michel; Sangiorgi, Luca; Pecora, Fabio; Reicherter, Kerstin; Nishimura, Gen; Spranger, Jürgen; Zabel, Bernhard; Superti-Furga, Andrea

2008-06-01

Deficiency of carbohydrate sulfotransferase 3 (CHST3; also known as chondroitin-6-sulfotransferase) has been reported in a single kindred so far and in association with a phenotype of severe chondrodysplasia with progressive spinal involvement. We report eight CHST3 mutations in six unrelated individuals who presented at birth with congenital joint dislocations. These patients had been given a diagnosis of either Larsen syndrome (three individuals) or humero-spinal dysostosis (three individuals), and their clinical features included congenital dislocation of the knees, elbow joint dysplasia with subluxation and limited extension, hip dysplasia or dislocation, clubfoot, short stature, and kyphoscoliosis developing in late childhood. Analysis of chondroitin sulfate proteoglycans in dermal fibroblasts showed markedly decreased 6-O-sulfation but enhanced 4-O-sulfation, confirming functional impairment of CHST3 and distinguishing them from diastrophic dysplasia sulphate transporter (DTDST)-deficient cells. These observations provide a molecular basis for recessive Larsen syndrome and indicate that recessive Larsen syndrome, humero-spinal dysostosis, and spondyloepiphyseal dysplasia Omani type form a phenotypic spectrum.

The Impact of Specialty on Cases Performed During Hand Surgery Fellowship Training.

PubMed

Silvestre, Jason; Upton, Joseph; Chang, Benjamin; Steinberg, David R

2018-03-07

Hand surgery fellowship programs in the United States are predominately sponsored by departments or divisions of orthopaedic surgery or plastic surgery. This study compares the operative experiences of hand surgery fellows graduating from orthopaedic or plastic surgery hand surgery fellowships. Operative case logs of 3 cohorts of hand surgery fellows graduating during the academic years of 2012-2013, 2013-2014, and 2014-2015 were analyzed. The median case volumes were compared by specialty via Mann-Whitney U tests. An arbitrary 1,000% change between the 90th and 10th percentiles of fellows was used as a threshold to highlight case categories with substantial variability. In this study, 413 orthopaedic hand surgery fellows (87%) and 62 plastic surgery hand surgery fellows (13%) were included. Plastic surgery fellows reported more cases in the following categories: wound closure with graft; wound reconstruction with flap; vascular repair, reconstruction, replantation, or microvascular; closed treatment of fracture or dislocation; nerve injury; and congenital (p < 0.05). Orthopaedic surgery fellows reported more cases in the following categories: wound irrigation and debridement fasciotomy or wound preparation; hand reconstruction or releases; wrist reconstruction, releases, or arthrodesis; forearm, elbow, or shoulder reconstruction or releases; hand fractures, dislocation, or ligament injury; wrist fractures or dislocations; forearm and proximal fractures or dislocations; miscellaneous insertion or removal of devices; shoulder arthroscopy, elbow arthroscopy, and wrist arthroscopy; decompression of tendon sheath, synovectomy, or ganglions; nerve decompression; Dupuytren; and tumor or osteomyelitis (p < 0.05). Plastic surgery fellows reported substantial variability for 12 case categories (range, 1,024% to 2,880%). Orthopaedic surgery fellows reported substantial variability for 9 case categories (range, 1,110% to 9,700%). Orthopaedic and plastic hand surgery fellowships afford disparate operative experiences. Understanding these differences may help to align prospective trainees with future career goals and to guide discussions to better standardize hand surgery training.

Treatment strategy and long-term functional outcome of traumatic elbow dislocation in childhood: a single centre study.

PubMed

Nussberger, G; Schädelin, S; Mayr, J; Studer, D; Zimmermann, P

2018-04-01

Traumatic elbow dislocation (TED) is the most common injury of large joints in children. There is an ongoing debate on the optimal treatment for TED. We aimed to assess the functional outcome after operative and nonoperative treatment of TED. We analysed the medical records of patients with TED treated at the University Children's Hospital, Basel, between March 2006 and June 2015. Functional outcome was assessed using the Mayo Elbow Performance Score (MEPS) and Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) Sport and Music Module score. These scores were compared between nonoperatively and operatively treated patients. A total of 37 patients (mean age 10.2 years, 5.2 to 15.3) were included. Of these, 21 (56.8%) children had undergone nonoperative treatment, with 16 (43.2%) patients having had operative treatment. After a mean follow-up of 5.6 years (1.2 to 5.9), MEPS and QuickDASH Sport and Music Module scores in the nonoperative group and operative group were similar: MEPS: 97.1 points (SD 4.6) versus 97.2 points (SD 2.6); 95% confidence interval (CI)-2.56 to 2.03); p = 0.53; QuickDASH Sport and Music Module score: 3.9 points (SD 6.1) versus 3.1 points (SD 4.6); 95% CI 2.60 to 4.17; p = 0.94. We noted no significant differences regarding the long-term functional outcome between the subgroup of children treated operatively versus those treated nonoperatively for TED with accompanying fractures of the medial epicondyle and medial condyle. Functional outcome after TED was excellent, independent of the treatment strategy. If clear indications for surgery are absent, a nonoperative approach for TED should be considered. Level III - therapeutic, retrospective, comparative study.

Medial Elbow Joint Space Increases With Valgus Stress and Decreases When Cued to Perform A Maximal Grip Contraction.

PubMed

Pexa, Brett S; Ryan, Eric D; Myers, Joseph B

2018-04-01

Previous research indicates that the amount of valgus torque placed on the elbow joint during overhead throwing is higher than the medial ulnar collateral ligament (UCL) can tolerate. Wrist and finger flexor muscle activity is hypothesized to make up for this difference, and in vitro studies that simulated activity of upper extremity musculature, specifically the flexor digitorum superficialis and flexor carpi ulnaris, support this hypothesis. To assess the medial elbow joint space at rest, under valgus stress, and under valgus stress with finger and forearm flexor contraction by use of ultrasonography in vivo. Controlled laboratory study. Participants were 22 healthy males with no history of elbow dislocation or UCL injury (age, 21.25 ± 1.58 years; height, 1.80 ± 0.08 m; weight, 79.43 ± 18.50 kg). Medial elbow joint space was measured by use of ultrasonography during 3 separate conditions: at rest (unloaded), under valgus load (loaded), and with a maximal grip contraction under a valgus load (loaded-contracted) in both limbs. Participants lay supine with their arm abducted 90° and elbow flexed 30° with the forearm in full supination. A handgrip dynamometer was placed in the participants' hand to grip against during the contracted condition. Images were reduced in ImageJ to assess medial elbow joint space. A 2-way (condition × limb) repeated-measures analysis of variance and Cohen's d effect sizes were used to assess changes in medial elbow joint space. Post hoc testing was performed with a Bonferroni adjustment to assess changes within limb and condition. The medial elbow joint space was significantly larger in the loaded condition (4.91 ± 1.16 mm) compared with the unloaded condition (4.26 ± 1.23 mm, P < .001, d = 0.712) and the loaded-contracted condition (3.88 ± 0.94 mm, P < .001, d = 1.149). No significant change was found between the unloaded and loaded-contracted conditions ( P = .137). Medial elbow joint space increases under a valgus load and then decreases when a maximal grip contraction is performed. This indicates that wrist and finger flexor muscle contraction may assist in limiting medial elbow joint space, a result similar to findings of previous research in vitro. Muscle activation of the upper extremity limits the medial elbow joint space, suggesting that injury prevention programs for throwing athletes should incorporate exercises for the elbow, wrist, and hand to limit excessive medial elbow joint space gapping during activities that create high valgus load.

New Design of a Soft Robotics Wearable Elbow Exoskeleton Based on Shape Memory Alloy Wire Actuators

PubMed Central

Cano, Enrique; Moreno, Luis; Blanco, Dolores

2017-01-01

The elbow joint is a complex articulation composed of the humeroulnar and humeroradial joints (for flexion-extension movement) and the proximal radioulnar articulation (for pronation-supination movement). During the flexion-extension movement of the elbow joint, the rotation center changes and this articulation cannot be truly represented as a simple hinge joint. The main goal of this project is to design and assemble a medical rehabilitation exoskeleton for the elbow with one degree of freedom for flexion-extension, using the rotation center for proper patient elbow joint articulation. Compared with the current solutions, which align the exoskeleton axis with the elbow axis, this offers an ergonomic physical human-robot interface with a comfortable interaction. The exoskeleton is actuated with shape memory alloy wire-based actuators having minimum rigid parts, for guiding the actuators. Thanks to this unusual actuation system, the proposed exoskeleton is lightweight and has low noise in operation with a simple design 3D-printed structure. Using this exoskeleton, these advantages will improve the medical rehabilitation process of patients that suffered stroke and will influence how their lifestyle will change to recover from these diseases and improve their ability with activities of daily living, thanks to brain plasticity. The exoskeleton can also be used to evaluate the real status of a patient, with stroke and even spinal cord injury, thanks to an elbow movement analysis. PMID:29104424

New Design of a Soft Robotics Wearable Elbow Exoskeleton Based on Shape Memory Alloy Wire Actuators.

PubMed

Copaci, Dorin; Cano, Enrique; Moreno, Luis; Blanco, Dolores

2017-01-01

The elbow joint is a complex articulation composed of the humeroulnar and humeroradial joints (for flexion-extension movement) and the proximal radioulnar articulation (for pronation-supination movement). During the flexion-extension movement of the elbow joint, the rotation center changes and this articulation cannot be truly represented as a simple hinge joint. The main goal of this project is to design and assemble a medical rehabilitation exoskeleton for the elbow with one degree of freedom for flexion-extension, using the rotation center for proper patient elbow joint articulation. Compared with the current solutions, which align the exoskeleton axis with the elbow axis, this offers an ergonomic physical human-robot interface with a comfortable interaction. The exoskeleton is actuated with shape memory alloy wire-based actuators having minimum rigid parts, for guiding the actuators. Thanks to this unusual actuation system, the proposed exoskeleton is lightweight and has low noise in operation with a simple design 3D-printed structure. Using this exoskeleton, these advantages will improve the medical rehabilitation process of patients that suffered stroke and will influence how their lifestyle will change to recover from these diseases and improve their ability with activities of daily living, thanks to brain plasticity. The exoskeleton can also be used to evaluate the real status of a patient, with stroke and even spinal cord injury, thanks to an elbow movement analysis.

The Snapping Elbow Syndrome as a Reason for Chronic Elbow Neuralgia in a Tennis Player - MR, US and Sonoelastography Evaluation.

PubMed

Łasecki, Mateusz; Olchowy, Cyprian; Pawluś, Aleksander; Zaleska-Dorobisz, Urszula

2014-01-01

Ulnar neuropathy is the second most common peripheral nerve neuropathy after median neuropathy, with an incidence of 25 cases per 100 000 men and 19 cases per 100 000 women each year. Skipping (snapping) elbow syndrome is an uncommon cause of pain in the posterior-medial elbow area, sometimes complicated by injury of the ulnar nerve. One of the reason is the dislocation of the abnormal insertion of the medial triceps head over the medial epicondyle during flexion and extension movements. Others are: lack of the Osboune fascia leading to ulnar nerve instability and focal soft tissue tumors (fibromas, lipomas, etc). Recurrent subluxation of the nerve at the elbow results in a tractional and frictional neuritis with classical symptoms of peripheral neuralgia. As far as we know snapping triceps syndrome had never been evaluated in sonoelastography. A 28yo semi-professional left handed tennis player was complaining about pain in posterior-medial elbow area. Initial US examination suggest golfers elbow syndrome which occurs quite commonly and has a prevalence of 0.3-0.6% in males and 0-3-1.1% in women and may be associated (approx. 50% of cases) with ulnar neuropathy. However subsequently made MRI revealed unusual distal triceps anatomy, moderate ulnar nerve swelling and lack of medial epicondylitis symptoms. Followed (second) US examination and sonoelastography have detected slipping of the both ulnar nerve and the additional band of the medial triceps head. Snapping elbow syndrome is a poorly known medical condition, sometimes misdiagnosed as the medial epicondylitis. It describes a broad range of pathologies and anatomical abnormalities. One of the most often reasons is the slipping of the ulnar nerve as the result of the Osborne fascia/anconeus epitrochlearis muscle absence. Simultaneously presence of two or more "snapping reasons" is rare but should be always taken under consideration. There are no sonoelastography studies describing golfers elbow syndrome, additional triceps band and ulnar neuritis. Our data suggest that the sonoelastography signs are similar to those seen in well described lateral epicondylitis syndrome, Achilles tendinitis and medial nerve neuralgia.

Ligamentous and capsular injuries to the metacarpophalangeal joints of the hand.

PubMed

Shah, Smiresh Suresh; Techy, Fernando; Mejia, Alfonso; Gonzalez, Mark H

2012-01-01

The mechanism of dorsal dislocation of the metacarpophalangeal (MCP) joint is with forced hyperextension of the joint and the main structure injured is the volar plate. A simple dislocation can be reduced by closed means whereas a complex dislocation cannot. Care must be taken not to put traction across the joint, which may cause the volar plate to slip into the joint, converting a simple dislocation into a complex dislocation. Volar dislocations are rare and mainly treated nonoperatively. Sagittal band injuries can be treated with extension splinting or surgical management with direct repair or reconstruction. A locked MCP joint can usually be treated with closed manipulation. This article discusses these injuries and management options.

Vertical Patellar Dislocation: Reduction by the Push Up and Rotate Method, A Case Report and Literature Review.

PubMed

Ahmad Khan, Hayat; Bashir Shah, Adil; Kamal, Younis

2016-11-01

Patellar dislocation is an emergency. Vertical patellar dislocation is rare, often seen in adolescents and mostly due to sports injuries or high-velocity trauma. Few cases have been reported in the literature. Closed or open reduction under general anesthesia is often needed. We report a case of vertical locked patellar dislocation in a 26-year-old male, which was reduced by a simple closed method under spinal anaesthesia. A literature review regarding the various methods of treatment is also discussed. A 26-year-old male experienced a trivial accident while descending stairs, sustaining patellar dislocation. The closed method of reduction was attempted, using a simple technique. Reduction was confirmed and postoperative rehabilitation was started. Follow-up was uneventful. Vertical patellar dislocations are encountered rarely in the emergency department. Adolescents are not the only victims, and high-velocity trauma is not the essential cause. Unnecessary manipulation should be avoided. The closed reduction method is simple, but the surgeon should be prepared for open reduction.

Snapping plicae associated with radiocapitellar chondromalacia.

PubMed

Antuna, S A; O'Driscoll, S W

2001-05-01

Painful snapping of the elbow joint is usually attributed to intra-articular loose bodies, instability, or medial dislocation of the triceps muscle over the medial epicondyle. We report our experience with 14 patients who were treated arthroscopically for snapping elbow that was found to be caused by hypertrophic synovial folds associated with radiocapitellar chondromalacia. Case series. The records of 14 patients who were treated arthroscopically for painful snapping elbows caused by intra-articular plicae were reviewed. There were 6 women and 8 men with an average age of 36 years (range, 27 to 48 years). Nine patients had had some type of trauma to the joint. Four patients had been previously diagnosed with lateral epicondylitis and 5 with intra-articular loose bodies. The average time from initial onset of symptoms to treatment was 13 months (range, 8 to 36 months). Average follow-up was 24 months (range, 6 to 66 months). All patients complained of painful snapping in the posterolateral or anterolateral aspect of the elbow. The snapping occurred between 90 degrees and 110 degrees of flexion with the forearm in pronation. In 7 patients, the snapping was reproducible by passively flexing the pronated elbow, which we refer to as the flexion-pronation test. At the time of arthroscopic surgery, all patients had a thickened synovial plica that would snap back and forward over the radial head, usually associated with a chondromalacic area on the radial head. Twelve patients had complete relief of their snapping after surgery. One patient in whom there was associated posterolateral rotatory elbow instability did not improve. One patient became asymptomatic for 4 years but then had recurrence of her symptoms, which persisted despite 2 subsequent arthroscopies. The presence of synovial plicae in the radiocapitellar joint must be considered in the differential diagnosis of painful snapping elbow. Arthroscopy confirms the diagnosis and allows excision of the plica.

Use of a shorter humeral stem in revision reverse shoulder arthroplasty.

PubMed

Wagner, Eric R; Statz, Joseph M; Houdek, Matthew T; Cofield, Robert H; Sánchez-Sotelo, Joaquín; Sperling, John W

2017-08-01

The purpose of this study was to examine the outcomes of revision reverse arthroplasty using short bone-preserving humeral components in revising a long-stemmed component. During a 7-year period, 39 patients who underwent revision reverse shoulder arthroplasty using the long to short humeral component technique were included. The mean age was 72 years. Prior implants used in the primary setting included anatomic (n = 26), hemiarthroplasty (n = 11), and reverse (n = 2). At a follow-up of 3 years (2-5), 5 shoulders (13%) required revision surgery, including 1 for a periprosthetic humerus fracture and 4 for glenoid component loosening. The survival free of revision for any reason and revision for humeral disease was 84% and 94%, respectively. One patient experienced a nondisplaced greater tuberosity fracture at 18 months postoperatively that healed without operative intervention. There were no dislocations or infections. Overall, patients experienced excellent overall improvements in their pain levels and shoulder motion (P < .001), with a postoperative 91% satisfaction rate as well as postoperative American Shoulder and Elbow Surgeons score of 68 and Simple Shoulder Test score of 6.7. At most recent radiographic follow-up, 1 (5%) patient had grade 3 humeral lucency. Preserving bone stock through conversion to a shorter reverse humeral stem in the revision setting is a reasonable option with good short- to intermediate-term results and low rates of humeral complications. Using the shorter stem components provides adequate stability and high rates of humeral component ingrowth. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

A continuum theory of edge dislocations

NASA Astrophysics Data System (ADS)

Berdichevsky, V. L.

2017-09-01

Continuum theory of dislocation aims to describe the behavior of large ensembles of dislocations. This task is far from completion, and, most likely, does not have a "universal solution", which is applicable to any dislocation ensemble. In this regards it is important to have guiding lines set by benchmark cases, where the transition from a discrete set of dislocations to a continuum description is made rigorously. Two such cases have been considered recently: equilibrium of dislocation walls and screw dislocations in beams. In this paper one more case is studied, equilibrium of a large set of 2D edge dislocations placed randomly in a 2D bounded region. The major characteristic of interest is energy of dislocation ensemble, because it determines the structure of continuum equations. The homogenized energy functional is obtained for the periodic dislocation ensembles with a random contents of the periodic cell. Parameters of the periodic structure can change slowly on distances of order of the size of periodic cells. The energy functional is obtained by the variational-asymptotic method. Equilibrium positions are local minima of energy. It is confirmed the earlier assertion that energy density of the system is the sum of elastic energy of averaged elastic strains and microstructure energy, which is elastic energy of the neutralized dislocation system, i.e. the dislocation system placed in a constant dislocation density field making the averaged dislocation density zero. The computation of energy is reduced to solution of a variational cell problem. This problem is solved analytically. The solution is used to investigate stability of simple dislocation arrays, i.e. arrays with one dislocation in the periodic cell. The relations obtained yield two outcomes: First, there is a state parameter of the system, dislocation polarization; averaged stresses affect only dislocation polarization and cannot change other characteristics of the system. Second, the structure of dislocation phase space is strikingly simple. Dislocation phase space is split in a family of subspaces corresponding to constant values of dislocation polarizations; in each equipolarization subspace there are many local minima of energy; for zero external stresses the system is stuck in a local minimum of energy; for non-zero slowly changing external stress, dislocation polarization evolves, while the system moves over local energy minima of equipolarization subspaces. Such a simple picture of dislocation dynamics is due to the presence of two time scales, slow evolution of dislocation polarization and fast motion of the system over local minima of energy. The existence of two time scales is justified for a neutral system of edge dislocations.

Dislocation-induced stress in polycrystalline materials: mesoscopic simulations in the dislocation density formalism

NASA Astrophysics Data System (ADS)

Berkov, D. V.; Gorn, N. L.

2018-06-01

In this paper we present a simple and effective numerical method which allows a fast Fourier transformation-based evaluation of stress generated by dislocations with arbitrary directions and Burgers vectors if the (site-dependent) dislocation density is known. Our method allows the evaluation of the dislocation stress using a rectangular grid with shape-anisotropic discretization cells without employing higher multipole moments of the dislocation interaction coefficients. Using the proposed method, we first simulate the stress created by relatively simple non-homogeneous distributions of vertical edge and so-called ‘mixed’ dislocations in a disk-shaped sample, which is necessary to understand the dislocation behavior in more complicated systems. The main part of our research is devoted to the stress distribution in polycrystalline layers with the dislocation density rapidly varying with the distance to the layer bottom. Considering GaN as a typical example of such systems, we investigate dislocation-induced stress for edge and mixed dislocations, having random orientations of Burgers vectors among crystal grains. We show that the rapid decay of the dislocation density leads to many highly non-trivial features of the stress distributions in such layers and study in detail the dependence of these features on the average grain size. Finally we develop an analytical approach which allows us to predict the evolution of the stress variance with the grain size and compare analytical predictions with numerical results.

A syndrome of dislocated hips and radial heads, carpal coalition, and short stature in Puerto Rican children.

PubMed

Steel, H H; Piston, R W; Clancy, M; Betz, R R

1993-02-01

An orthopaedic syndrome that apparently had not been reported previously was identified in twenty-three children. Characteristics shared by all twenty-three children included Hispanic descent, residence in Puerto Rico, bilateral dislocation of the hip, dislocated radial heads, short stature, and other osseous anomalies. Twelve dislocated hips in six patients were not treated. All of these hips were functioning satisfactorily at the time of the review, but only four of the children had reached skeletal maturity. Sixteen hips in eight patients remained reduced after closed reduction. Of these eight patients, the four who were skeletally immature at the time of the review had a satisfactory result, and the four who were skeletally mature had an unsatisfactory result because of discomfort or fibrous ankylosis. Eighteen hips in nine patients were treated with a reduction augmented by some form of operation. All of these hips redislocated. Of the forty-six elbows in the twenty-three children, thirty-three were dislocated, as seen clinically and radiographically; eight were normal, both clinically and radiographically; and there was dysplasia at the radiocapitellar articulation of the remaining five. Twenty of the twenty-three children were found to have carpal coalitions. Fourteen children had scoliosis, and five of them were managed with spinal arthrodesis and correction. Three patients had an anomaly of the cervical spine, with one deformity causing symptoms and signs that were treated with decompression. Eight patients had talipes cavus bilaterally, which was not treated.

A modified surgical technique for reconstruction of an acute acromioclavicular joint dislocation

PubMed Central

Marchie, Anthony; Kumar, Arun; Catre, Melanio

2009-01-01

We report a modified surgical technique for reconstruction of coracoclavicular and acromioclavicular ligaments after acute dislocation of acromioclavicular joint using suture anchors. We have repaired 3 consecutive type III acromioclavicular dislocations with good results. This technique is simple and safe and allows anatomical reconstruction of the ligaments in acute dislocations. PMID:20671868

Revision to Reverse Total Shoulder Arthroplasty Restores Stability for Patients With Unstable Shoulder Prostheses.

PubMed

Hernandez, Nicholas M; Chalmers, Brian P; Wagner, Eric R; Sperling, John W; Cofield, Robert H; Sanchez-Sotelo, Joaquin

2017-11-01

Instability after shoulder arthroplasty remains a complication with limited salvage options. Reoperation for instability with anatomic designs has led to high rates of persistent instability, therefore we aimed to evaluate the use of RSA for treatment of prosthetic instability. (1) After revision shoulder arthroplasty to a reverse prosthesis (RSA), what is the survivorship free from dislocations at 2 and 5 years? (2) What factors are associated with dislocations? (3) What is the survivorship free from revision after revision to RSA? (4) From preoperation to postrevision to RSA, what are the clinical outcomes-the proportion of patients with moderate to severe pain, shoulder elevation and external rotation ROM, American Shoulder and Elbow Surgeons scores, and Simple Shoulder Test scores? All shoulder arthroplasties revised for prosthetic instability using RSA components between January 2004 and July 2014 were retrospectively studied. During the period in question, we performed 82 revisions for instability of an anatomic total shoulder arthroplasty (TSA) (n = 62), hemiarthroplasty (n = 13), or reverse TSA (n = 7). We typically used a reverse TSA to treat this problem, but we identified 12 treated in other ways, including revision of a TSA to hemiarthroplasty (n = 3), revision of a reverse TSA to hemiarthroplasty (n = 2), revision of hemiarthroplasty to a hemiarthroplasty (n = 1), and revision of an anatomic TSA to another anatomic TSA (n = 6). This left 70 patients for evaluation; of those, 65 (93%) were available for analysis at a mean of 3 years (range, 2-10 years). A total of seven patients died. Eight of the 65 shoulders were not evaluated during the last 5 years, including three in patients who died earlier. The mean age of the patients at the time of revision RSA was 65 years (range, 40-89 years). Data were obtained from a longitudinally maintained institutional joint registry. Instability was defined as severe subluxation confirmed on clinical and radiographic examinations. We evaluated pain and ROM, and Kaplan-Meier curves were used to estimate survivorship. The survivorship free from dislocation at 2 and 5 years was 87% (95% CI, 80%-94%) and 79% (95% CI, 67%-91%) respectively, with 10 of 65 (15%) patients having an episode of dislocation after revision surgery. Persistent instability was more common in those with a BMI greater than 35 kg/m 2 (hazard ratio [HR], 5; 95% CI, 2-16; p = 0.008) and prior hemiarthroplasty (HR, 5; 95% CI, 2-16; p = 0.005), whereas patients who had undergone a previous TSA were less likely to have persistent instability (HR, 0.08; 95% CI, 0.0-0.30; p < 0.001) The survival free from rerevision for any indication at 2 and 5 years was 85% (95% CI, 76%-94%) and 78% (95% CI, 66%-90%) respectively; with the numbers available, we were not able to find associated factors. Fewer patients had moderate or severe pain after revision to RSA (preoperative: 48 of 65 [74%]; postoperative: nine of 65 [14%]; p < 0.001). After surgery, patients showed improvement in shoulder elevation (preoperative: 42° [± 30°], postoperative: 112° [42°]; mean difference, 70° [95% CI, - 83 o to 57°]; p < 0.001) and external rotation (preoperative: 20° [± 22°], postoperative: 42° [± 23°]; mean difference, 22° [95% CI, - 30° to - 14°]; p < 0.001). American Shoulder and Elbow Surgeons scores improved (preoperative: 21 [± 10], postoperative: 68 [± 14], mean difference, 46 [95% CI, - 58 to - 35]; p < 0.001); where a higher score is better. Simple Shoulder Test scores also improved (preoperative: 2/12 [± 2], postoperative: 7/12 [± 3]; mean difference, 5 [95% CI, - 7 to - 2.17]; p < 0.001); where a higher score is better. Revision RSA for prosthetic instability after shoulder arthroplasty is associated with reasonable implant survival and few complications. Approximately one in seven patients will have a recurrent dislocation. In patients with persistent instability or with risk factors for instability, consideration should be given for use of larger glenospheres and increasing the lateral offset at the time of RSA. Level IV, therapeutic study.

A study on operative findings and pathogenic factors in ulnar neuropathy at the elbow.

PubMed

Kojima, T; Kurihara, K; Nagano, T

1979-01-01

A study was made of operative findings obtained in 44 cases of ulnar nerve neuropathy at the elbow in an attempt to help elucidate the pathogenetic factors for the condition. Distinction must be made between Lig. epitrochleo-anconeum or a ligament-like thickening at the same site and the tendinous arch of M. flexor carpi ulnaris. These 2 sites constitute the entrapment points for the condition. A thick tendinous arch, Lig. epitrochleo-anconeum of M. anconeus epitrochlearis deters the ulnar nerve from being mobile, thereby contributing to the development of neuropathy with trauma acting as a precipitating factor. Dislocation of the ulnar nerve cannot be considered a factor of major etiologic significance. An important part is played by the tendinous arch in the pathogenesis of neuropathy, regardless of whether it is in association with ganglion, osteochondromatosis or osteoarthritis. In surgery for ulnar neuropathy decompression of the nerve is of primary necessity. Division of the tendinous arch is mandatory. Medial epicondylectomy may be added as required.

Tension band wiring of the olecranon: is it really a dynamic principle of osteosynthesis?

PubMed

Brink, P R G; Windolf, M; de Boer, P; Brianza, S; Braunstein, V; Schwieger, K

2013-04-01

The tension band principle as applied to transverse olecranon fractures fixed by tension band wiring is based on the premise that distraction forces on the outer cortex of the ulna during elbow flexion are converted to compression forces on the articular surface of the olecranon at the fracture site. In view of some clinical outcomes, where hardware failure and secondary dislocations occur, the question arises if the dynamic compression theory is correct. Compressive forces during active flexion and extension after tension band wiring of a transverse osteotomy of the olecranon were measured in 6 fresh frozen human cadaveric models using a pressure-sensor in the osteotomy gap. We could collect 30 measurements during active flexion and 30 during active extension. Active flexion did not cause any compressive forces in the osteotomy gap. Extension with the humerus in an upright position and the elbow actively extended causes some compression (0.37-0.51 MPa) at the articular surface comparing with active flexion (0.2 MPa) due to gravity forces. Posterior, there was no significant pressure difference observed (0.41-0.45 versus 0.36-0.32 MPa) between active flexion and extension. The tension band wiring principle only exists during active extension in a range of 30-120° of flexion of the elbow. Postoperative exercise programs should be modified in order to prevent loss of compression at the fracture site of transverse olecranon fractures, treated with tension band wiring when the elbow is mobilised. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evaluation of a computational model to predict elbow range of motion

PubMed Central

Nishiwaki, Masao; Johnson, James A.; King, Graham J. W.; Athwal, George S.

2014-01-01

Computer models capable of predicting elbow flexion and extension range of motion (ROM) limits would be useful for assisting surgeons in improving the outcomes of surgical treatment of patients with elbow contractures. A simple and robust computer-based model was developed that predicts elbow joint ROM using bone geometries calculated from computed tomography image data. The model assumes a hinge-like flexion-extension axis, and that elbow passive ROM limits can be based on terminal bony impingement. The model was validated against experimental results with a cadaveric specimen, and was able to predict the flexion and extension limits of the intact joint to 0° and 3°, respectively. The model was also able to predict the flexion and extension limits to 1° and 2°, respectively, when simulated osteophytes were inserted into the joint. Future studies based on this approach will be used for the prediction of elbow flexion-extension ROM in patients with primary osteoarthritis to help identify motion-limiting hypertrophic osteophytes, and will eventually permit real-time computer-assisted navigated excisions. PMID:24841799

Elbow arthroscopy: setup, portal placement, and simple procedures.

PubMed

Ahmad, Christopher S; Vitale, Mark A

2011-01-01

Elbow arthroscopy has become an accepted treatment for numerous elbow conditions, including loose bodies, lateral epicondylitis, contractures, painful osteophytes, synovitis, osteochondritis dissecans, synovial plica, and osteoarthritis. It is absolutely necessary that the treating surgeon have complete knowledge of elbow anatomy. Three options exist for patient positioning: supine, prone, and lateral decubitus. Standard arthroscopic probes, grasping forceps, punches, and motorized shavers and burrs are used in the procedure. Retractors are essential for visualizing, exposing, and protecting nerves. Specially designed capsular biters can be used to develop a plane between the capsule and the surrounding soft tissues to facilitate capsulotomy and capsulectomy. Among elbow arthroscopists, the sequence of portal placement varies; however, there is little variation in the exact location of portal placement because of neurovascular constraints. Loose body removal and extensor carpi radialis brevis release for lateral epicondylitis are common procedures suitable for the beginning arthroscopist. For beginning and advanced procedures, the surgeon's skill and competence must be at a level consistent with the procedure to avoid complications.

“Conjugate Channeling” Effect in Dislocation Core Diffusion: Carbon Transport in Dislocated BCC Iron

PubMed Central

Ishii, Akio; Li, Ju; Ogata, Shigenobu

2013-01-01

Dislocation pipe diffusion seems to be a well-established phenomenon. Here we demonstrate an unexpected effect, that the migration of interstitials such as carbon in iron may be accelerated not in the dislocation line direction , but in a conjugate diffusion direction. This accelerated random walk arises from a simple crystallographic channeling effect. is a function of the Burgers vector b, but not , thus a dislocation loop possesses the same everywhere. Using molecular dynamics and accelerated dynamics simulations, we further show that such dislocation-core-coupled carbon diffusion in iron has temperature-dependent activation enthalpy like a fragile glass. The 71° mixed dislocation is the only case in which we see straightforward pipe diffusion that does not depend on dislocation mobility. PMID:23593255

"Conjugate channeling" effect in dislocation core diffusion: carbon transport in dislocated BCC iron.

PubMed

Ishii, Akio; Li, Ju; Ogata, Shigenobu

2013-01-01

Dislocation pipe diffusion seems to be a well-established phenomenon. Here we demonstrate an unexpected effect, that the migration of interstitials such as carbon in iron may be accelerated not in the dislocation line direction ξ, but in a conjugate diffusion direction. This accelerated random walk arises from a simple crystallographic channeling effect. c is a function of the Burgers vector b, but not ξ, thus a dislocation loop possesses the same everywhere. Using molecular dynamics and accelerated dynamics simulations, we further show that such dislocation-core-coupled carbon diffusion in iron has temperature-dependent activation enthalpy like a fragile glass. The 71° mixed dislocation is the only case in which we see straightforward pipe diffusion that does not depend on dislocation mobility.

Effect of lateral offset center of rotation in reverse total shoulder arthroplasty: a biomechanical study.

PubMed

Henninger, Heath B; Barg, Alexej; Anderson, Andrew E; Bachus, Kent N; Burks, Robert T; Tashjian, Robert Z

2012-09-01

Lateral offset center of rotation (COR) reduces the incidence of scapular notching and potentially increases external rotation range of motion (ROM) after reverse total shoulder arthroplasty (rTSA). The purpose of this study was to determine the biomechanical effects of changing COR on abduction and external rotation ROM, deltoid abduction force, and joint stability. A biomechanical shoulder simulator tested cadaveric shoulders before and after rTSA. Spacers shifted the COR laterally from baseline rTSA by 5, 10, and 15 mm. Outcome measures of resting abduction and external rotation ROM, and abduction and dislocation (lateral and anterior) forces were recorded. Resting abduction increased 20° vs native shoulders and was unaffected by COR lateralization. External rotation decreased after rTSA and was unaffected by COR lateralization. The deltoid force required for abduction significantly decreased 25% from native to baseline rTSA. COR lateralization progressively eliminated this mechanical advantage. Lateral dislocation required significantly less force than anterior dislocation after rTSA, and both dislocation forces increased with lateralization of the COR. COR lateralization had no influence on ROM (adduction or external rotation) but significantly increased abduction and dislocation forces. This suggests the lower incidence of scapular notching may not be related to the amount of adduction deficit after lateral offset rTSA but may arise from limited impingement of the humeral component on the lateral scapula due to a change in joint geometry. Lateralization provides the benefit of increased joint stability, but at the cost of increasing deltoid abduction forces. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Rapid feedback responses correlate with reach adaptation and properties of novel upper limb loads.

PubMed

Cluff, Tyler; Scott, Stephen H

2013-10-02

A hallmark of voluntary motor control is the ability to adjust motor patterns for novel mechanical or visuomotor contexts. Recent work has also highlighted the importance of feedback for voluntary control, leading to the hypothesis that feedback responses should adapt when we learn new motor skills. We tested this prediction with a novel paradigm requiring that human subjects adapt to a viscous elbow load while reaching to three targets. Target 1 required combined shoulder and elbow motion, target 2 required only elbow motion, and target 3 (probe target) required shoulder but no elbow motion. This simple approach controlled muscle activity at the probe target before, during, and after the application of novel elbow loads. Our paradigm allowed us to perturb the elbow during reaching movements to the probe target and identify several key properties of adapted stretch responses. Adapted long-latency responses expressed (de-) adaptation similar to reaching errors observed when we introduced (removed) the elbow load. Moreover, reaching errors during learning correlated with changes in the long-latency response, showing subjects who adapted more to the elbow load displayed greater modulation of their stretch responses. These adapted responses were sensitive to the size and direction of the viscous training load. Our results highlight an important link between the adaptation of feedforward and feedback control and suggest a key part of motor adaptation is to adjust feedback responses to the requirements of novel motor skills.

Osteochondritis Dissecans Involving the Trochlear Groove Treated With Retrograde Drilling

PubMed Central

Kaji, Yoshio; Nakamura, Osamu; Yamaguchi, Konosuke; Yamamoto, Tetsuji

2015-01-01

Abstract Osteochondritis dissecans (OCD) occurs frequently in the humeral capitellum of the upper extremity, whereas OCD involving the trochlear groove (trochlear groove OCD) is rarely reported. A standard treatment for trochlear groove OCD has therefore not been determined, although several methods have been tried. The case of a 14-year-old male gymnast with bilateral trochlear groove OCD is presented. Retrograde drilling from the lateral condyle of the humerus was applied for the OCD lesion of the left elbow, since it was larger in size than that in the right elbow and was symptomatic. Conversely, since the right lesion was small and asymptomatic, it was managed conservatively. After treatment, consolidation of the OCD lesions was observed in both elbows. However, the time to healing was shorter in the left elbow treated surgically than in the right elbow managed conservatively. In conclusion, retrograde drilling is a very simple and minimally invasive treatment. This case suggests that retrograde drilling for trochlear groove OCD may be a useful procedure that may accelerate the healing process for OCD lesions. PMID:26356703

Ibuprofen impairs capsulolabral healing in a rat model of anterior glenohumeral instability.

PubMed

Packer, Jonathan D; Varthi, Arya G; Zhu, David S; Javier, Frances G; Young, Jason D; Garver, Jennie V; Henry, Havalee; Tommasini, Steven M; Blaine, Theodore A

2018-02-01

Failure of glenoid labrum and capsular healing after glenohumeral dislocation can lead to persistent shoulder instability. The purpose of this study was to determine the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on the healing glenoid labrum and capsule after glenohumeral dislocation in a rat model. Sixty-six rats had surgically induced anterior-inferior labral tears and anterior glenohumeral dislocation. Postoperatively, the animals were assigned to either normal (n = 32) or ibuprofen drinking water (n = 31). Animals were euthanized at 2 and 4 weeks postoperatively for biomechanical testing and histologic analysis. The maximum load increased from 2 to 4 weeks after injury in the NSAID groups but not in the control groups. At 2 weeks, the maximum load was lower in the NSAID group compared with the control group. In a matched comparison between injured and uninjured limbs, the maximum load was significantly decreased in the injured limb of the 2-week NSAID group. At 4 weeks, the NSAID group had decreased stiffness compared with the 4-week control group. In a new rat model of glenohumeral instability, the postinjury administration of ibuprofen resulted in decreased capsulolabral healing. A matched pair analysis of injured to uninjured limbs supported the findings of impaired healing in the NSAID-treated animals. These findings demonstrate that the use of NSAIDs after glenohumeral dislocation may impair capsulolabral healing and should be limited or avoided to optimize glenohumeral stability. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Radial head reconstruction in elbow fracture-dislocation: monopolar or bipolar prosthesis?

PubMed

Hartzler, Robert U; Morrey, Bernard F; Steinmann, Scott P; Llusa-Perez, Manuel; Sanchez-Sotelo, Joaquin

2014-07-01

Monopolar and bipolar radial head prosthetic arthroplasties have been used successfully to treat elbow fracture-dislocation with unsalvageable radial head fractures. The relative stability of these two designs in different clinical situations is a topic of ongoing investigation. We tested the effects of monopolar and bipolar fixed-neck prosthetic radial head implants on improvement in elbow coronal and axial plane laxity in a terrible triad biomechanical model that accounted for lateral collateral ligament integrity and the presence of a transverse coronoid fracture. Kinematic data were collected on six fresh-frozen cadaveric upper extremities tested with passive motion throughout the flexion arc. Varus and valgus gravity stress were applied with the wrist in neutral position. A lateral collateral ligament reconstruction was simulated. We assessed instability after radial head resection and reconstruction with either a monopolar or bipolar implant in the presence of a transversely fractured (Regan and Morrey Type 2) or fixed coronoid process. With collateral ligament integrity, no difference was detected, with the numbers available, in valgus laxity between implants under valgus stress (p = 1.0). Laxity improvement with each prosthesis was higher when the coronoid was fractured (mean ± SD: monopolar: 7.4° ± 1.6°, p < 0.001; bipolar: 6.4° ± 1.6°, p = 0.003) than when it was fixed (monopolar: 4.0° ± 1.6°, p = 0.02; bipolar: 4.2° ± 1.6°, p = 0.01). With the numbers available, there was no difference in external rotation laxity between implants under valgus stress (p = 1.0). The greatest stabilizing effect of the prostheses occurred when the coronoid was fractured (monopolar: 3.3° ± 1.2°, p = 0.15; bipolar: 3.3° ± 1.2°, p = 0.17). Radial head arthroplasty offered no substantial stability under varus stress for varus or internal rotation laxity. In our terrible triad cadaveric model, coronoid fixation was effective in improving varus laxity with a monopolar or bipolar prosthesis in place. Also, both types of prostheses were effective in improving valgus and external rotation laxity to the elbow, regardless of coronoid status. With collateral ligaments reconstructed, no large kinematic differences were noted between implants regardless of the varus-valgus position or whether the coronoid was fractured or fixed. The data from our cadaveric model support the use of either implant type in terrible triad injuries if the collateral ligaments are intact or reconstructed.

Use of commercially available foam pipe insulation as a protective device for wounds over the elbow joint area in five dogs.

PubMed

Pavletic, Michael M

2011-11-01

4 large-breed dogs were referred because of nonhealing skin wounds involving the elbow joint area of several weeks to months in duration. One additional large-breed dog was evaluated because of a draining abscess with overlying skin necrosis. Previous attempts at closing each wound over the elbow joint area had been unsuccessful. At the time of hospital admission, open wounds had variable degrees of bacterial contamination and infection. Open wounds over the elbow joint area were closed by use of bipedicle advancement flaps or direct suture apposition of opposing sides of the wound. Lengths of pipe insulation were applied to the forelimb in a fashion to prevent contact pressure to the olecranon for a prolonged period (4 to 13 weeks) after surgery. All wounds healed completely. Release incisions (donor areas) healed by second intention within 3 weeks after surgery. One dog developed periostitis of the olecranon, which responded to antimicrobial administration. A second dog developed a skin bacterial infection below the surgical area that was markedly resistant to antimicrobials. The layered application of commercially available foam pipe insulation provided a simple and economical protective device after closure of problematic skin wounds involving the elbow joint area. Prolonged protection of the olecranon area helped to assure healing was complete and skin coverage was sufficiently stable to reduce the risk of reinjury after removal of the device. Each patient was able to use the involved forelimb during the treatment period. Paired bipedicle advancement flaps (release incisions) were particularly useful for closing small to moderate defects overlying the olecranon in which simple apposition was not feasible.

A micro S-shaped optical fiber temperature sensor based on dislocation fiber splice

NASA Astrophysics Data System (ADS)

Yan, Haitao; Li, Pengfei; Zhang, Haojie; Shen, Xiaoyue; Wang, Yongzhen

2017-12-01

We fabricated a simple, compact, and stable temperature sensor based on an S-shaped dislocated optical fiber. The dislocation optical fiber has two splice points, and we obtained the optimal parameters based on the theory and our experiment, such as the dislocation amount and length of the dislocation optical fiber. According to the relationship between the temperature and the peak wavelength shift, the temperature of the environment can be obtained. Then, we made this fiber a micro bending as S-shape between the two dislocation points, and the S-shaped micro bending part could release stress with the change in temperature and reduce the effect of stress on the temperature measurement. This structure could solve the problem of sensor distortion caused by the cross response of temperature and stress. We measured the S-shaped dislocation fiber sensor and the dislocation fiber without S-shape under the same environment and conditions, and the S-shaped dislocation fiber had the advantages of the stable reliability and good linearity.

The Prevalence, Rate of Progression, and Treatment of Elbow Flexion Contracture in Children with Brachial Plexus Birth Palsy

PubMed Central

Sheffler, Lindsey C.; Lattanza, Lisa; Hagar, Yolanda; Bagley, Anita; James, Michelle A.

2012-01-01

Background: Elbow flexion contracture is a well-known complication of brachial plexus birth palsy that adversely affects upper-extremity function. The prevalence, risk factors, and rate of progression of elbow flexion contracture associated with brachial plexus birth palsy have not been established, and the effectiveness of nonoperative treatment involving nighttime splinting or serial casting has not been well studied. Methods: The medical records of 319 patients with brachial plexus birth palsy who had been seen at our institution between 1992 and 2009 were retrospectively reviewed to identify patients with an elbow flexion contracture (≥10°). The chi-square test for trend and the Kaplan-Meier estimator were used to evaluate risk factors for contracture, including age, sex, and the extent of brachial plexus involvement. Longitudinal models were used to estimate the rate of contracture progression and the effectiveness of nonoperative treatment. Results: An elbow flexion contracture was present in 48% (152) of the patients with brachial plexus birth palsy. The median age of onset was 5.1 years (range, 0.25 to 14.8 years). The contracture was ≥30° in 36% (fifty-four) of these 152 patients and was accompanied by a documented radial head dislocation in 6% (nine). The prevalence of contracture increased with increasing age (p < 0.001) but was not significantly associated with sex or with the extent of brachial plexus involvement. The magnitude of the contracture increased by 4.4% per year before treatment (p < 0.01). The magnitude of the contracture decreased by 31% when casting was performed (p < 0.01) but thereafter increased again at the same rate of 4.4% per year. The magnitude of the contracture did not improve when splinting was performed but the rate of increase thereafter decreased to <0.1% per year (p = 0.04). Conclusions: The prevalence of elbow flexion contracture in children with brachial plexus birth palsy may be greater than clinicians perceive. The prevalence increased with patient age but was not significantly affected by sex or by the extent of brachial plexus involvement. Serial casting may initially improve severe contractures, whereas nighttime splinting may prevent further progression of milder contractures. Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence. PMID:22398733

A new technique for repair of a dislocated sternoclavicular joint using a sternal tension cable system.

PubMed

Janson, Jacques T; Rossouw, Gawie J

2013-02-01

An unstable anterior or posterior sternoclavicular joint dislocation can cause severe morbidity with poor shoulder movement and strength. These dislocations need to be repaired, which can be challenging. Many different procedures have been described to obtain a stable joint fixation with varying results. We report a new technique for repairing a sternoclavicular joint dislocation by using a figure-of-eight sternal cable system. This procedure is relatively simple and reproducible to create a stable and functional sternoclavicular joint. Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Chronic bilateral dislocation of temporomandibular joint.

PubMed

Shakya, S; Ongole, R; Sumanth, K N; Denny, C E

2010-01-01

Dislocation of the condyle of the mandible is a common condition that may occur in an acute or chronic form. It is characterised by inability to close the mouth with or without pain. Dislocation has to be differentiated from subluxation which is a self reducible condition. Dislocation can occur in any direction with anterior dislocation being the commonest one. Various predisposing factors have been associated with dislocation like muscle fatigue and spasm, the defect in the bony surface like shallow articular eminence, and laxity of the capsular ligament. People with defect in collagen synthesis like Ehler Danlos syndrome, Marfan syndrome are said to be genetically predisposed to this condition. Various treatment modalities have been used ranging from conservative techniques to surgical methods. Acute dislocations can be reduced manually or with conservative approach and recurrent and chronic cases can be reduced by surgical intervention. Though the dislocation in our case was 4 months a simple manual reduction proved to be successful. We believe that manual reduction can be attempted as first line of treatment prior to surgical intervention.

Fast Fourier transform discrete dislocation dynamics

NASA Astrophysics Data System (ADS)

Graham, J. T.; Rollett, A. D.; LeSar, R.

2016-12-01

Discrete dislocation dynamics simulations have been generally limited to modeling systems described by isotropic elasticity. Effects of anisotropy on dislocation interactions, which can be quite large, have generally been ignored because of the computational expense involved when including anisotropic elasticity. We present a different formalism of dislocation dynamics in which the dislocations are represented by the deformation tensor, which is a direct measure of the slip in the lattice caused by the dislocations and can be considered as an eigenstrain. The stresses arising from the dislocations are calculated with a fast Fourier transform (FFT) method, from which the forces are determined and the equations of motion are solved. Use of the FFTs means that the stress field is only available at the grid points, which requires some adjustments/regularizations to be made to the representation of the dislocations and the calculation of the force on individual segments, as is discussed hereinafter. A notable advantage of this approach is that there is no computational penalty for including anisotropic elasticity. We review the method and apply it in a simple dislocation dynamics calculation.

Harnessing atomistic simulations to predict the rate at which dislocations overcome obstacles

NASA Astrophysics Data System (ADS)

Saroukhani, S.; Nguyen, L. D.; Leung, K. W. K.; Singh, C. V.; Warner, D. H.

2016-05-01

Predicting the rate at which dislocations overcome obstacles is key to understanding the microscopic features that govern the plastic flow of modern alloys. In this spirit, the current manuscript examines the rate at which an edge dislocation overcomes an obstacle in aluminum. Predictions were made using different popular variants of Harmonic Transition State Theory (HTST) and compared to those of direct Molecular Dynamics (MD) simulations. The HTST predictions were found to be grossly inaccurate due to the large entropy barrier associated with the dislocation-obstacle interaction. Considering the importance of finite temperature effects, the utility of the Finite Temperature String (FTS) method was then explored. While this approach was found capable of identifying a prominent reaction tube, it was not capable of computing the free energy profile along the tube. Lastly, the utility of the Transition Interface Sampling (TIS) approach was explored, which does not need a free energy profile and is known to be less reliant on the choice of reaction coordinate. The TIS approach was found capable of accurately predicting the rate, relative to direct MD simulations. This finding was utilized to examine the temperature and load dependence of the dislocation-obstacle interaction in a simple periodic cell configuration. An attractive rate prediction approach combining TST and simple continuum models is identified, and the strain rate sensitivity of individual dislocation obstacle interactions is predicted.

Size-Tuned Plastic Flow Localization in Irradiated Materials at the Submicron Scale

NASA Astrophysics Data System (ADS)

Cui, Yinan; Po, Giacomo; Ghoniem, Nasr

2018-05-01

Three-dimensional discrete dislocation dynamics (3D-DDD) simulations reveal that, with reduction of sample size in the submicron regime, the mechanism of plastic flow localization in irradiated materials transitions from irradiation-controlled to an intrinsic dislocation source controlled. Furthermore, the spatial correlation of plastic deformation decreases due to weaker dislocation interactions and less frequent cross slip as the system size decreases, thus manifesting itself in thinner dislocation channels. A simple model of discrete dislocation source activation coupled with cross slip channel widening is developed to reproduce and physically explain this transition. In order to quantify the phenomenon of plastic flow localization, we introduce a "deformation localization index," with implications to the design of radiation-resistant materials.

Changes in pennation with joint angle and muscle torque: in vivo measurements in human brachialis muscle.

PubMed Central

Herbert, R D; Gandevia, S C

1995-01-01

1. Estimates of pennation in human muscles are usually obtained from cadavers. In this study, pennation of human brachialis was measured in vivo using sonography. Effects of static and dynamic changes in elbow angle and torque were investigated. 2. Pennation was measured in eight subjects using an 80 mm, 5 MHz, linear-array ultrasound transducer to generate sagittal images of the brachialis during maximal and submaximal isometric contractions at various elbow angles. It was shown that estimates of pennation were reproducible, representative of measurements made throughout the belly of the muscle and not distorted by compression of the muscle with the transducer or rotation of the muscle out of the plane of the transducer. 3. Mean resting pennation was 9.0 +/- 2.0 deg (S.D., range 6.5-12.9 deg). When the muscle was relaxed there was no effect of elbow angle on pennation. However, during a maximal isometric contraction (MVC), with the elbow flexed to 90 deg, pennation increased non-linearly with elbow torque to between 22 and 30 deg (mean 24.7 +/- 2.4 deg). The effect of increasing torque was small when the elbow was fully extended. The relationship between elbow angle, elbow torque and brachialis pennation suggests that the relaxed brachialis muscle is slack over much of its physiological range of lengths. 4. There was no hysteresis in the relationship between torque and pennation during slow isometric contractions (0.2 MVC s-1), and the relationship between elbow angle and pennation was similar during slow shortening and lengthening contractions. 5. Two consequences follow from these findings. Firstly, intramuscular mechanics are complex and simple planar models of muscles underestimate the increases in pennation which occur during muscle contraction. Second, spindle afferents from relaxed muscles may not encode joint angle over the full range of movement. Images Figure 2 PMID:7602542

Effect of deltoid tension and humeral version in reverse total shoulder arthroplasty: a biomechanical study.

PubMed

Henninger, Heath B; Barg, Alexej; Anderson, Andrew E; Bachus, Kent N; Tashjian, Robert Z; Burks, Robert T

2012-04-01

No clear recommendations exist regarding optimal humeral component version and deltoid tension in reverse total shoulder arthroplasty (TSA). A biomechanical shoulder simulator tested humeral versions (0°, 10°, 20° retroversion) and implant thicknesses (-3, 0, +3 mm from baseline) after reverse TSA in human cadavers. Abduction and external rotation ranges of motion as well as abduction and dislocation forces were quantified for native arms and arms implanted with 9 combinations of humeral version and implant thickness. Resting abduction angles increased significantly (up to 30°) after reverse TSA compared with native shoulders. With constant posterior cuff loads, native arms externally rotated 20°, whereas no external rotation occurred in implanted arms (20° net internal rotation). Humeral version did not affect rotational range of motion but did alter resting abduction. Abduction forces decreased 30% vs native shoulders but did not change when version or implant thickness was altered. Humeral center of rotation was shifted 17 mm medially and 12 mm inferiorly after implantation. The force required for lateral dislocation was 60% less than anterior and was not affected by implant thickness or version. Reverse TSA reduced abduction forces compared with native shoulders and resulted in limited external rotation and abduction ranges of motion. Because abduction force was reduced for all implants, the choice of humeral version and implant thickness should focus on range of motion. Lateral dislocation forces were less than anterior forces; thus, levering and inferior/posterior impingement may be a more probable basis for dislocation (laterally) than anteriorly directed forces. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Are “knife and fork” good enough for day case surgery of resistant tennis elbow?

PubMed Central

Govindaswamy, Raja; Elbouni, Tariq; Chambler, Andrew F. W.

2008-01-01

This observational retrospective study was performed on 22 consecutive patients treated surgically in a day surgery unit for resistant tennis elbow to ascertain the effectiveness of the “knife and fork” procedure. All patients had an unfavourable response to nonsurgical treatment lasting at least six months. A simple and inexpensive “knife and fork” technique yielded excellent results in 90.5% of patients and a high percentage (95.2%) of satisfied patients at an average follow-up of two years. There were no fair or poor results and no complications. We conclude that the “knife and fork” technique is a simple and dependable day case procedure. In the present National Health Service (NHS) era of tariff and “payment by results”, this approach is more cost effective than an arthroscopic alternative. PMID:19096844

Outcome of Percutaneous Release of Tennis Elbow: A Non-Randomized Controlled Trial Study.

PubMed

Panthi, Sagar; Khatri, Kishor; Kharel, Krishna; Byanjankar, Subin; Shrestha, Rahul; Sharma, Jay R; Vaishya, Raju; Agarwal, Amit Kumar; Vijay, Vipul

2017-01-02

Tennis elbow is a common disorder of the upper extremity. It can be treated conservatively in the majority of patients, but some resistant cases eventually can be treated by percutaneous release with good functional outcome. This non-randomized control trial was conducted at the Department of Orthopaedics Surgery in a tertiary care hospital from July 2015 to June 2016 on 50 patients who underwent percutaneous release of the common extensor origin using an 18 gauge hypodermic needle. These patients did not respond to conservative treatment including rest, nonsteroidal anti-inflammatory drugs (NSAIDS) and local steroid injections. The outcome was graded as Excellent, Good, Fair, and Poor. Fifty patients (50 elbows) were included in the study. Thirty-two patients were female (64%), and 18 were male (36%). The right side was affected in 37 patients (74%) and left side in 13 (26%). The time taken to achieve a completely pain-free elbow ranged from one day to two months (average of 26.2 days). Those who did not achieve a pain-free elbow had a residual pain of 1.5 to six on the visual analogue scale (VAS) (average 2.32). Excellent outcome was noticed in 24 patients (48%); Good result in eight patients (36% ); Fair in four patients (eight percent) and Poor in four patients (eight percent). Tennis elbow probably results from the degenerative tear of the common extensor origin, and a percutaneous tenotomy using an 18 gauge hypodermic needle is a simple, safe, patient-friendly, efficient, and easily reproducible method of treating tennis elbow in those who are resistant to conservative treatment, and it can be done as an outpatient procedure.

Outcome of Percutaneous Release of Tennis Elbow: A Non-Randomized Controlled Trial Study

PubMed Central

Khatri, Kishor; Kharel, Krishna; Byanjankar, Subin; Shrestha, Rahul; Sharma, Jay R; Vaishya, Raju; Agarwal, Amit kumar; Vijay, Vipul

2017-01-01

Background Tennis elbow is a common disorder of the upper extremity. It can be treated conservatively in the majority of patients, but some resistant cases eventually can be treated by percutaneous release with good functional outcome. Materials and methods This non-randomized control trial was conducted at the Department of Orthopaedics Surgery in a tertiary care hospital from July 2015 to June 2016 on 50 patients who underwent percutaneous release of the common extensor origin using an 18 gauge hypodermic needle. These patients did not respond to conservative treatment including rest, nonsteroidal anti-inflammatory drugs (NSAIDS) and local steroid injections. The outcome was graded as Excellent, Good, Fair, and Poor. Results Fifty patients (50 elbows) were included in the study. Thirty-two patients were female (64%), and 18 were male (36%). The right side was affected in 37 patients (74%) and left side in 13 (26%). The time taken to achieve a completely pain-free elbow ranged from one day to two months (average of 26.2 days). Those who did not achieve a pain-free elbow had a residual pain of 1.5 to six on the visual analogue scale (VAS) (average 2.32). Excellent outcome was noticed in 24 patients (48%); Good result in eight patients (36% ); Fair in four patients (eight percent) and Poor in four patients (eight percent). Conclusion Tennis elbow probably results from the degenerative tear of the common extensor origin, and a percutaneous tenotomy using an 18 gauge hypodermic needle is a simple, safe, patient-friendly, efficient, and easily reproducible method of treating tennis elbow in those who are resistant to conservative treatment, and it can be done as an outpatient procedure. PMID:28168130

Impact of screw and edge dislocations on the thermal conductivity of individual nanowires and bulk GaN: a molecular dynamics study.

PubMed

Termentzidis, Konstantinos; Isaiev, Mykola; Salnikova, Anastasiia; Belabbas, Imad; Lacroix, David; Kioseoglou, Joseph

2018-02-14

We report the thermal transport properties of wurtzite GaN in the presence of dislocations using molecular dynamics simulations. A variety of isolated dislocations in a nanowire configuration are analyzed and found to considerably reduce the thermal conductivity while impacting its temperature dependence in a different manner. Isolated screw dislocations reduce the thermal conductivity by a factor of two, while the influence of edge dislocations is less pronounced. The relative reduction of thermal conductivity is correlated with the strain energy of each of the five studied types of dislocations and the nature of the bonds around the dislocation core. The temperature dependence of the thermal conductivity follows a physical law described by a T -1 variation in combination with an exponent factor that depends on the material's nature, type and the structural characteristics of the dislocation core. Furthermore, the impact of the dislocation density on the thermal conductivity of bulk GaN is examined. The variation and absolute values of the total thermal conductivity as a function of the dislocation density are similar for defected systems with both screw and edge dislocations. Nevertheless, we reveal that the thermal conductivity tensors along the parallel and perpendicular directions to the dislocation lines are different. The discrepancy of the anisotropy of the thermal conductivity grows with increasing density of dislocations and it is more pronounced for the systems with edge dislocations. Besides the fundamental insights of the presented results, these could also be used for the identification of the type of dislocations when one experimentally obtains the evolution of thermal conductivity with temperature since each type of dislocation has a different signature, or one could extract the density of dislocations with a simple measurement of thermal anisotropy.

[Treatment of proximal ulna and olecranon fractures by reconstruction plate combined with tension band wiring].

PubMed

Teng, Lin; Zhong, Gang; Xiao, Cong; Liu, Gang; Xiang, Zhou; Cen, Shiqiang; Huang, Fuguo

2011-01-01

OBJECTIVE To review the efficacy of reconstruction plate combined with tension band wiring for treating proximal ulna and olecranon fractures. Between November 2004 and September 2009, 10 patients with proximal ulna and olecranon fractures were treated by reconstruction plate combined with tension band wiring. There were 6 males and 4 females with an average age of 45.3 years (range, 21-75 years). Five fractures were caused by traffic accident, 2 by falling from height, 2 by tumbling, and 1 by a machine strangulation. The locations were the left side and the right side in 5 cases respectively. One case was open fracture (Gustilo II) and the other 9 were closed fractures. Olecranon fractures included 4 cases of traverse fractures and 6 cases of comminuted fractures, and proximal ulna fractures included 6 cases of comminuted fractures and 4 cases of oblique fractures. The combined fractures included 6 radial head fractures, 4 coronoid process fractures, 2 proximal humerus fractures, and 3 scapula fractures; other injury included 1 elbow dislocation and 1 shoulder dislocation. Two patients had secondary operation; the other 8 patients received the primary operations and the time from injury to operation varied from 7 days to 20 days, with an average of 11 days. One case had infection at the incision 1 week after operation, and recovered after 2 months of antibiotics and debridement; incisions healed by first intention in other 9 patients. All patients were followed up 12-64 months (mean, 40.5 months). The X-ray films showed that fracture healing was achieved at 10-24 weeks (mean, 12 weeks). There was no ulnar nerve symptom in all cases. Heterotopic ossification occurred in 1 case at 2 months and stiffness of the elbow in 1 case at 3 months after operation; they were both cured after symptomatic treatment. Proximal migration of Kirschner wires was found in 1 case at 6 months after operation, whose implants were taken out at 9 months after the first operation because fracture had healed. At last follow-up, the flexion and extension are of the elbow averaged 92.8 degrees (range, 23-130 degrees), and the arc of forearm rotation averaged 124.4 degrees (range, 42-175 degrees). According to the American Hospital for Special Surgery (HSS) evaluation method, the results were classified as excellent in 6 cases, good in 2, fair in 1, and poor in 1. Treating proximal ulna and olecranon fractures by reconstruction plate combined with tension band wiring allows patients to do postoperative exercise early and could effectively avoid complications.

A combined dislocation fan-finite element (DF-FE) method for stress field simulation of dislocations emerging at the free surfaces of 3D elastically anisotropic crystals

NASA Astrophysics Data System (ADS)

Balusu, K.; Huang, H.

2017-04-01

A combined dislocation fan-finite element (DF-FE) method is presented for efficient and accurate simulation of dislocation nodal forces in 3D elastically anisotropic crystals with dislocations intersecting the free surfaces. The finite domain problem is decomposed into half-spaces with singular traction stresses, an infinite domain, and a finite domain with non-singular traction stresses. As such, the singular and non-singular parts of the traction stresses are addressed separately; the dislocation fan (DF) method is introduced to balance the singular traction stresses in the half-spaces while the finite element method (FEM) is employed to enforce the non-singular boundary conditions. The accuracy and efficiency of the DF method is demonstrated using a simple isotropic test case, by comparing it with the analytical solution as well as the FEM solution. The DF-FE method is subsequently used for calculating the dislocation nodal forces in a finite elastically anisotropic crystal, which produces dislocation nodal forces that converge rapidly with increasing mesh resolutions. In comparison, the FEM solution fails to converge, especially for nodes closer to the surfaces.

Treatment of post-traumatic elbow deformities in children with the Ilizarov distraction osteogenesis technique.

PubMed

Özkan, Cenk; Deveci, Mehmet Ali; Tekin, Mustafa; Biçer, Ömer Sunkar; Gökçe, Kadir; Gülşen, Mahir

2017-01-01

The present study assessed functional and radiographic outcomes of distraction osteogenesis treatment of post-traumatic elbow deformities in children. Eight children were treated between 2008 and 2013 for post-traumatic elbow deformities using distraction osteogenesis. Mean age at time of operation was 10.9 years. Six patients had varus and 2 had valgus deformity. Magnitude of correction, fixator index, complications, carrying angle, and elbow range of motion were assessed. Functional results were graded according to protocol of Bellemore et al. Mean follow-up was 43 months. Mean preoperative varus deformity in 6 patients was 29.2° and valgus deformity in 2 patients was 28.5°. Preoperative flexion and extension of elbow were 123.8° and -10.6°, respectively. Mean carrying angle was 9° valgus at last follow-up. Mean flexion and extension were 134.4° and -6.0°, respectively. Change in carrying angle was statistically significant (p = 0.002). There were 2 grade 1 pin tract infections and 1 diaphyseal fracture of humerus. Functional outcome was rated excellent in 7 patients and good in 1 patient. Ilizarov distraction osteogenesis is a valuable alternative in treatment of elbow deformities in children. The surgical technique is simple and correction is adjustable. Gradual correction prevents possible neurovascular complications and minimally invasive surgery produces less scarring. Compliance of patient and family is key factor in the success of the outcome. Level IV, therapeutic study. Copyright © 2016 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

[A clinical study and analysis of congenital lenticular dislocation (35 cases)].

PubMed

Guo, X; Mao, W; Chen, Y; Ma, Q; Zeng, L; Luo, T

1991-12-01

Thirty-five cases of congenital lenticular dislocation seen in our Center since 1985 have been studied and analyzed clinically. By the survey of pedigrees and examination of these patients, including ocular, systemic, skeletal X-ray, psychocardiogram, and urinary sodium-nitroprusside test, 21 cases were diagnosed as Marfan's syndrome, 6 cases as simple ectopia lentis, 3 cases as Weill-Marchesani's syndrome, 4 cases as aniridia and 1 case as homecys tinuria. We found that the most significant ocular manifestation of congenital lenticular dislocation was reduction in visual acuity. The severity of visual disturbance varied with the types of dislocation and the visual deficiency was closely related to the intermediate-grade (II) dislocation of the lens. Examination of ERG showed normal function in most of the patients. From this, we believe that the major cause of visual reduction in congenital lenticular dislocation is lenticular myopia and astigmatism. There fore, early diagnosis and effective correction of vision should be emphasized to prevent the occurrence of amblyopia.

Statistics of dislocation pinning at localized obstacles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dutta, A.; Bhattacharya, M., E-mail: mishreyee@vecc.gov.in; Barat, P.

2014-10-14

Pinning of dislocations at nanosized obstacles like precipitates, voids, and bubbles is a crucial mechanism in the context of phenomena like hardening and creep. The interaction between such an obstacle and a dislocation is often studied at fundamental level by means of analytical tools, atomistic simulations, and finite element methods. Nevertheless, the information extracted from such studies cannot be utilized to its maximum extent on account of insufficient information about the underlying statistics of this process comprising a large number of dislocations and obstacles in a system. Here, we propose a new statistical approach, where the statistics of pinning ofmore » dislocations by idealized spherical obstacles is explored by taking into account the generalized size-distribution of the obstacles along with the dislocation density within a three-dimensional framework. Starting with a minimal set of material parameters, the framework employs the method of geometrical statistics with a few simple assumptions compatible with the real physical scenario. The application of this approach, in combination with the knowledge of fundamental dislocation-obstacle interactions, has successfully been demonstrated for dislocation pinning at nanovoids in neutron irradiated type 316-stainless steel in regard to the non-conservative motion of dislocations. An interesting phenomenon of transition from rare pinning to multiple pinning regimes with increasing irradiation temperature is revealed.« less

Biceps tenodesis is a viable option for salvage of failed SLAP repair.

PubMed

Werner, Brian C; Pehlivan, Hakan C; Hart, Joseph M; Lyons, Matthew L; Gilmore, C Jan; Garrett, Cara B; Carson, Eric W; Diduch, David R; Miller, Mark D; Brockmeier, Stephen F

2014-08-01

Outcomes of arthroscopic superior labral anterior-posterior (SLAP) repairs have been well reported with generally favorable outcomes. Unfortunately, a percentage of patients remain dissatisfied or suffer further injury after SLAP repair and may seek additional treatment. The purpose of this study was to evaluate the surgical outcomes of biceps tenodesis for failed SLAP repairs. A retrospective review of all patients undergoing biceps tenodesis was completed. Inclusion criteria were previous SLAP repair and subsequent revision biceps tenodesis. Exclusion criteria were additional shoulder procedures including rotator cuff repair, instability procedures, and preoperative frozen shoulder. Objective outcomes were postoperative assessments with Constant score, American Shoulder and Elbow Surgeons score, Single Assessment Numeric Evaluation, Simple Shoulder Test, and Veterans RAND 36-Item Health Survey. Physical examination was conducted to determine postoperative range of motion and strength compared with the nonoperative shoulder. A cohort of 24 patients was identified, and of these, 17 patients (71%) completed the study at 2 years' follow-up. The average postoperative Constant score was 84.4; American Shoulder and Elbow Surgeons score, 75.5; Single Assessment Numeric Evaluation score, 73.1%; Simple Shoulder Test score, 9.2; and Veterans RAND 36-Item Health Survey score, 76.1. Postoperative range of motion of the operative shoulder returned to near that of the asymptomatic nonoperative shoulder. Workers' compensation status led to inferior results. Options for patients with a failed prior SLAP repair are limited. As a salvage operation for failed SLAP repair, biceps tenodesis serves the majority of patients well, with favorable outcomes by validated measures and excellent shoulder range of motion and elbow strength at 2 years' follow-up. Workers' compensation status may predispose patients to poorer outcomes. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Management of distal humeral coronal shear fractures

PubMed Central

Yari, Shahram S; Bowers, Nathan L; Craig, Miguel A; Reichel, Lee M

2015-01-01

Coronal shear fractures of the distal humerus are rare, complex fractures that can be technically challenging to manage. They usually result from a low-energy fall and direct compression of the distal humerus by the radial head in a hyper-extended or semi-flexed elbow or from spontaneous reduction of a posterolateral subluxation or dislocation. Due to the small number of soft tissue attachments at this site, almost all of these fractures are displaced. The incidence of distal humeral coronal shear fractures is higher among women because of the higher rate of osteoporosis in women and the difference in carrying angle between men and women. Distal humeral coronal shear fractures may occur in isolation, may be part of a complex elbow injury, or may be associated with injuries proximal or distal to the elbow. An associated lateral collateral ligament injury is seen in up to 40% and an associated radial head fracture is seen in up to 30% of these fractures. Given the complex nature of distal humeral coronal shear fractures, there is preference for operative management. Operative fixation leads to stable anatomic reduction, restores articular congruity, and allows initiation of early range-of-motion movements in the majority of cases. Several surgical exposure and fixation techniques are available to reconstruct the articular surface following distal humeral coronal shear fractures. The lateral extensile approach and fixation with countersunk headless compression screws placed in an anterior-to-posterior fashion are commonly used. We have found a two-incision approach (direct anterior and lateral) that results in less soft tissue dissection and better outcomes than the lateral extensile approach in our experience. Stiffness, pain, articular incongruity, arthritis, and ulnohumeral instability may result if reduction is non-anatomic or if fixation fails. PMID:25984515

Open inferior capsular shift for multidirectional shoulder instability in adolescents with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome.

PubMed

Vavken, Patrick; Tepolt, Frances A; Kocher, Mininder S

2016-06-01

The objective of this study was to assess the outcome of open inferior capsular shift for multidirectional shoulder instability in patients with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome. Data were obtained for 18 open inferior capsular shift surgeries in 15 adolescent patients with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome with a mean follow-up of 7.5 years. End points were subjective clinical outcome (pain, stability, satisfaction, return to sport), objective clinical outcome (recurrence, complications), and functional outcome scores (American Shoulder and Elbow Surgeons, 11-item version of the Disabilities of Arm, Shoulder and Hand). Thirteen patients (87%) reported improved pain and stability and were satisfied with the procedure. Nine patients (64%) were able to return to sports. One patient (7%) was dissatisfied with continuous pain and recurrent instability and considered a surgical failure. Seven patients (47%) reported no further episodes of instability. The mean American Shoulder and Elbow Surgeons score at a mean of 7.5 years of follow-up was 88 ± 10 points, and the mean score for the 11-item version of the Disabilities of Arm, Shoulder and Hand was 14 ± 14 points. The management of multidirectional shoulder instability in adolescent patients with generalized ligamentous hyperlaxity or Ehlers-Danlos syndrome is challenging. Open inferior capsular shift results in improvement in subjective and objective shoulder function and stability in adolescent patients with ligamentous hyperlaxity or Ehlers-Danlos who have failed nonoperative treatment. We found no effect of the recalled number of prior dislocations, laterality, and type of hyperlaxity on subjective and objective clinical outcomes. Level IV; Case Series; Treatment Study. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Predictors of surgical revision after in situ decompression of the ulnar nerve.

PubMed

Krogue, Justin D; Aleem, Alexander W; Osei, Daniel A; Goldfarb, Charles A; Calfee, Ryan P

2015-04-01

This study was performed to identify factors associated with the need for revision surgery after in situ decompression of the ulnar nerve for cubital tunnel syndrome. This case-control investigation examined all patients treated at one institution with open in situ decompression for cubital tunnel syndrome between 2006 and 2011. The case patients were 44 failed decompressions that required revision, and the controls were 79 randomly selected patients treated with a single operation. Demographic data and disease-specific data were extracted from the medical records. The rate of revision surgery after in situ decompression was determined from our 5-year experience. A multivariate logistic regression model was used based on univariate testing to determine predictors of revision cubital tunnel surgery. Revision surgery was required in 19% (44 of 231) of all in situ decompressions performed during the study period. Predictors of revision surgery included a history of elbow fracture or dislocation (odds ratio [OR], 7.1) and McGowan stage I disease (OR, 3.2). Concurrent surgery with in situ decompression was protective against revision surgery (OR, 0.19). The rate of revision cubital tunnel surgery after in situ nerve decompression should be weighed against the benefits of a less invasive procedure compared with transposition. When considering in situ ulnar nerve decompression, prior elbow fracture as well as patients requesting surgery for mild clinically graded disease should be viewed as risk factors for revision surgery. Patient factors often considered relevant to surgical outcomes, including age, sex, body mass index, tobacco use, and diabetes status, were not associated with a greater likelihood of revision cubital tunnel surgery. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Dislocation dynamics in non-convex domains using finite elements with embedded discontinuities

NASA Astrophysics Data System (ADS)

Romero, Ignacio; Segurado, Javier; LLorca, Javier

2008-04-01

The standard strategy developed by Van der Giessen and Needleman (1995 Modelling Simul. Mater. Sci. Eng. 3 689) to simulate dislocation dynamics in two-dimensional finite domains was modified to account for the effect of dislocations leaving the crystal through a free surface in the case of arbitrary non-convex domains. The new approach incorporates the displacement jumps across the slip segments of the dislocations that have exited the crystal within the finite element analysis carried out to compute the image stresses on the dislocations due to the finite boundaries. This is done in a simple computationally efficient way by embedding the discontinuities in the finite element solution, a strategy often used in the numerical simulation of crack propagation in solids. Two academic examples are presented to validate and demonstrate the extended model and its implementation within a finite element program is detailed in the appendix.

Binary dislocation junction formation and strength in hexagonal close-packed crystals

DOE PAGES

Wu, Chi -Chin; Aubry, Sylvie; Arsenlis, Athanasios; ...

2015-12-17

This work examines binary dislocation interactions, junction formation and junction strengths in hexagonal close-packed ( hcp ) crystals. Through a line-tension model and dislocation dynamics (DD) simulations, the interaction and dissociation of different sets of binary junctions are investigated involving one dislocation on the (011¯0) prismatic plane and a second dislocation on one of the following planes: (0001) basal, (11¯00) prismatic, (11¯01) primary pyramidal, or (2¯112) secondary pyramidal. Varying pairs of Burgers vectors are chosen from among the common types the basal type < a > 1/3 < 112¯0 >, prismatic type < c > <0001>, and pyramidal type 1/3 < 112¯3¯ >. For binary interaction due to dislocation intersection, both the analytical results and DD-simulations indicate a relationship between symmetry of interaction maps and the relative magnitude of the Burgers vectors that constitute the junction. Using analytical formulae, a simple regressive model is also developed to represent the junction yield surface. The equation is treated as a degenerated super elliptical equation to quantify the aspect ratio and tilting angle. Lastly, the results provide analytical insights on binary dislocation interactions that may occur in general hcp metals.« less

An approach to enhance self-compensation capability in paper-based devices for chemical sensing.

PubMed

Lo, Shih-Jie; Chen, Kuan-Hung; Yao, Da-Jeng

2015-12-01

This paper describes a simple design for increasing the tolerance of reagent dislocation on a paper-based platform using a combination of wax-treated paper and a vortex mixer. To date, massive budgetary funds are required in the biotechnological industry to develop new applications; a large part of that cost is attributable to the screening of specific chemical compounds. Here, we propose using a liquid-handling robot to automatically deposit selected reagents on a paper-based platform. We also present a preliminary concept approach for developing a reagent placing device with simple and inexpensive features. A defect of inaccuracy was observed between droplet location and test well location after viewing the performance of the liquid-handling robot on our paper-based platform. Because of dislocation error resulting from robotic reagent placement, we decided to apply an external, rotational force following droplet placement in order to compensate for the distance of reagent dislocation. Note, the largest distance of reagent dislocation was determined by examining the results of altering applied reagent volume, but not concentration, in volumes from 5 µL to 30 µL in a series of experiments. As a result of these experiments, we observed that dislocation was positively affected by an increase in applied volume. A colorimetric assay for nitrite detection was also performed to confirm the feasibility of this method. This work, we believe, can minimize the cost of chemical compound screening for the biotechnological industry. Copyright © 2015 Elsevier B.V. All rights reserved.

Microplastic flow in SIC/AL composites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shi, N.; Arsenault, R.J.

Experimentally it has been determined that if a composite containing a reinforcement which has a different (in general lower) thermal coefficient of expansion as compared to the matrix, then upon cooling from the processing or annealing temperature, plastic relaxation of the misfit strain will occur. Also, experimentally it has been shown that as the size of the reinforcement is increased, i.e., from small spheres to large spheres, there is a decrease in the summation of the effective plastic strain in the matrix. In other words there is a decrease in the average dislocation density in the matrix. However, if themore » shape of the reinforcement is changed from spherical to short fiber to continuous filament, then the dislocation density increases. This experimental data is obtained at a constant volume fraction. A very simple model of plastic relaxation based on prismatic punching of dislocations from the interface can account for the decrease in the dislocation density with an increase reinforcement size, and the increase in dislocation density when changing the shape from a sphere to a continuous filament. A FEM analysis of the shape factor is also capable of predicting the correct trend. However, at present the continuum mechanics methods that have been investigated can not predict the size dependence. A simple model to explain the size effect in Al{sub 2}O{sub 3}/NiAl composites based on the deformation characteristics of NiAl will be discussed.« less

[Clavicular hook plate combined with suture anchor for the treatment of type Tossy III chronic acromioclavicular dislocation].

PubMed

Xu, Zhi-Bin; Wang, Jin

2014-05-01

To observe the clinical effects of clavicular hook plate combined with suture anchor in treating type Tossy III chronic acromioclavicular dislocation. From January 2008 to December 2012,18 patients with type Tossy III chronic acromioclavicular dislocation were treated with clavicular hook plate and suture anchor. There were 12 males and 6 females, aged from 20 to 56 years old with an average of 31.5 years. Ten cases were left dislocation and 8 cases were right dislocation. Operation time was 3 weeks to 4 months after injury with a mean of 1.8 months. Functional exercise was adopted 2 weeks after operation. And Karlsson standard was used to evaluate curative effect. All patients were followed up for 6 to 24 months with an average of 16 months. According to Karlsson standard, 17 cases were excellent and 1 was poor. Clavicular hook plate combined with suture anchor can repair conoid ligament and trapezoid ligament in treating type Tossy III chronic acromioclavicular dislocation, and had advantages of simple operation, less trauma, stable fixation, it can obtain satisfactory effects.

Mobile application MDDCS for modeling the expansion dynamics of a dislocation loop in FCC metals

NASA Astrophysics Data System (ADS)

Kirilyuk, Vasiliy; Petelin, Alexander; Eliseev, Andrey

2017-11-01

A mobile version of the software package Dynamic Dislocation of Crystallographic Slip (MDDCS) designed for modeling the expansion dynamics of dislocation loops and formation of a crystallographic slip zone in FCC-metals is examined. The paper describes the possibilities for using MDDCS, the application interface, and the database scheme. The software has a simple and intuitive interface and does not require special training. The user can set the initial parameters of the experiment, carry out computational experiments, export parameters and results of the experiment into separate text files, and display the experiment results on the device screen.

Management of Chronic Recurrent Dislocation of Temporomandibular Joint Using 'U' Shaped Graft: A New Restrictive Technique.

PubMed

Gadre, Kiran; Singh, Divya; Gadre, Pushkar; Halli, Rajshekhar

2017-06-01

Numerous procedures have been described for the treatment of chronic recurrent dislocation of the temporo-mandibular joint (TMJ), either in the form of enhancement or restriction of the condylar movement, with their obvious merits and demerits. We present a new technique of using U shaped iliac bone graft to restrict the condylar movement and its advantages over the conventional techniques.We have used this technique successfully in 8 cases where Dautrey's procedure had failed with follow up period of 2 years. No patient complained of recurrent dislocation postoperatively. This a very simple and effective technique where other procedures have failed.

Bilateral recurrent discloation of the patella associated with below knee amputation: A case report

PubMed Central

Batra, Sumit; Kumar, Ratnesh; Lenka, Prasanna

2005-01-01

Background Recurrent dislocation of the patella in patients with below knee amputation is a known entity. Abnormally high-riding patella (patella alta) and medial patellofemoral ligament insufficiency in these patients predisposes them to patellar instability. The established treatment of this problem is surgical realignment. Case presentation A 25 year old male patient with bilateral below knee amputation presented with bilateral recurrent dislocation of the patella while walking on knees on uneven ground. Clinical and radiographic studies showed patella alta. A simple shoe modification was used to treat this patient. Conclusions A simple shoe modification can be used to treat such a condition which is otherwise treated surgically. PMID:15717922

Quantifying selective elbow movements during an exergame in children with neurological disorders: a pilot study.

PubMed

van Hedel, Hubertus J A; Häfliger, Nadine; Gerber, Corinna N

2016-10-21

It is difficult to distinguish between restorative and compensatory mechanisms underlying (pediatric) neurorehabilitation, as objective measures assessing selective voluntary motor control (SVMC) are scarce. We aimed to quantify SVMC of elbow movements in children with brain lesions. Children played an airplane game with the glove-based YouGrabber system. Participants were instructed to steer an airplane on a screen through a cloud-free path by correctly applying bilateral elbow flexion and extension movements. Game performance measures were (i) % time on the correct path and (ii) similarity between the ideal flight path and the actually flown path. SVMC was quantified by calculating a correlation coefficient between the derivative of the ideal path and elbow movements. A therapist scored whether the child had used compensatory movements. Thirty-three children with brain lesions (11 girls; 12.6 ± 3.6 years) participated. Clinical motor and cognitive scores correlated moderately with SVMC (0.50-0.74). Receiver Operating Characteristics analyses showed that SVMC could differentiate well and better than clinical and game performance measures between compensatory and physiological movements. We conclude that a simple measure assessed while playing a game appears promising in quantifying SVMC. We propose how to improve the methodology, and how this approach can be easily extended to other joints.

Accumulated distribution of material gain at dislocation crystal growth

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rakin, V. I., E-mail: rakin@geo.komisc.ru

2016-05-15

A model for slowing down the tangential growth rate of an elementary step at dislocation crystal growth is proposed based on the exponential law of impurity particle distribution over adsorption energy. It is established that the statistical distribution of material gain on structurally equivalent faces obeys the Erlang law. The Erlang distribution is proposed to be used to calculate the occurrence rates of morphological combinatorial types of polyhedra, presenting real simple crystallographic forms.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gibert, Ivan, E-mail: gibert1993@mail.ru; Kiseleva, Svetlana, E-mail: kisielieva1946@mail.ru; Popova, Natalya, E-mail: natalya-popova-44@mail.ru

The investigation of excess dislocation density accumulation in the deformed polycrystalline austenitic steel was carried out using transmission electron microscopy (TEM). The distributions of the excess dislocation density in the grains of the deformed austenitic steel with different bending types were obtained and plotted. It was established that in the austenitic polycrystalline steel at the deformation degrees ε = 14 and 25 % the distributions of the excess dislocation density are multimodal. In both cases the grain with compound bending is more stressed. The values of the average excess dislocation density in the grains with the compound and simple bendingmore » are less at ε = 25 % than that at ε = 14 %. This is explained by a significant relaxation of the internal stresses in steel with the increase of the deformation degree from 14 % to 25 %. The increase of the number of twinning systems and the material volume fraction covered by twinning leads to the internal stress relaxation and consequently to the increase of the excess dislocation density. The presence of microtwins in the deformed material has an influence on the distribution of the excess dislocation density. In the deformed polycrystalline austenitic steel the number of grains with compound bending is increased with the increase of the plastic deformation degree.« less

Effects of solutes on dislocation nucleation from grain boundaries

DOE PAGES

Borovikov, Valery; Mendelev, Mikhail I.; King, Alexander H.

2016-12-27

When grain sizes are reduced to the nanoscale, grain boundaries (GB) become the dominant sources of the dislocations that enable plastic deformation. Here, we present the first molecular dynamics (MD) study of the effect of substitutional solutes on the dislocation nucleation process from GBs during uniaxial tensile deformation. A simple bi-crystal geometry is utilized in which the nucleation and propagation of dislocations away from a GB is the only active mechanism of plastic deformation. Solutes with atomic radii both larger and smaller than the solvent atomic radius were considered. Although the segregation sites are different for the two cases, bothmore » produce increases in the stress required to nucleate a dislocation. MD simulations at room temperature revealed that this increase in the nucleation stress is associated with changes of the GB structure at the emission site caused by dislocation emission, leading to increases in the heats of segregation of the solute atoms, which cannot diffuse to lower-energy sites on the timescale of the nucleation event. These results contribute directly to understanding the strength of nanocrystalline materials, and suggest suitable directions for nanocrystalline alloy design leading toward structural applications.« less

[Clinical applications of sternoclavicular hook plate for the treatment of sternoclavicular joint dislocation].

PubMed

Chen, Fang-Hu; Zhao, Xiao-Ping; Zheng, Wen-Biao; Zeng, Han-Bing; Ran, Bo; Huang, Hui; Wang, Hai-Bao

2013-05-01

To observe the clinical therapeutic effects of sternoclavicular hook plate for the treatment of sternoclavicular joint dislocation. From June 2010 to June 2012, 7 patients with sternoclavicular joint dislocation were treated with sternoclavicular hook plate fixation. Among the 7 patients, 5 patients were male and 2 patients were female, and the average age was 42.3 years, ranging from 38 to 54 years. The course of the disease ranged from 1 to 4 weeks. All the patients had trauma history. The clinical manifestations included: obvious swelling and pain of sternoclavicular joint, restricted shoulder joint activity. The sternoclavicular joint dislocation was proved by preoperative X-ray and CT. The postoperative curative effect was evaluated according to Rockwood scoring method. According to Rockwood scoring method, the excellent results obtained in 6 cases, good in 1. There were no complications such as internal fixation loosening or broken, second dislocation, pain in the sternoclavicular joint, and deformity. The function of shoulder joint was good, and the limb activity was free and no pain appeared. The sternoclavicular hook plate for the treatment of sternoclavicular joint dislocation has follow advantages: simple procedure, stable fixation, definite therapeutic effects.

Local Variability of the Peierls Barrier of Screw Dislocations in Ta-10W.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Foiles, Stephen M.

2017-10-01

It is well know that the addition of substitutional elements changes the mechanical behavior of metals, a effect referred to solid solution hardening. For body-centered-cubic (BCC) metals, screw dislocation play a key role in the mechanical properties. Here the detailed modification of the Peierls barrier for screw dislocation motion in Ta with W substitutional atoms is computing using density functional theory (DFT). A reduced order model (ROM) of the influence of W substitution on the Peierls barrier is developed. The mean field change in the Peierls barrier for a Ta10W alloy is determined and shown to be larger than anticipatedmore » based on simple elasticity considerations. The ROM could be used in future calculations to determine the local variability of the Peierls barrier and the resultant influence on the motion of screw dislocation in this alloy.« less

K-wire and tension band wire fixation in treating sternoclavicular joint dislocation.

PubMed

Chen, Qing-yu; Cheng, Shao-wen; Wang, Wei; Lin, Zhong-qin; Zhang, Wei; Kou, Dong-quan; Shen, Yue; Ying, Xiao-zhou; Cheng, Xiao-jie; Lv, Chuan-zhu; Peng, Lei

2011-02-01

To evaluate the feasibility and therapeutic effect of treating sternoclavicular joint dislocation by K-wire and tension band wire fixation, and to improve the safety and stability of this technique. This study consisted of 9 cases, 6 males and 3 females with the mean age of 25 years (range, 9-62 years). The causes were traffic accident in 7 cases, falling in 1 case and fight in 1 case. The duration from injury to operation was 2 hours to 7 days. There were 5 left dislocations and 4 right dislocations; 8 anterior dislocations and 1 posterior dislocation, including one combined with left scapular fracture and one with left olecranon fracture. Open reduction and internal fixation using K-wires and tension band wires were performed to treat dislocations. All patients were followed up for 6 to 24 months, 10 months on average. According to Rockwood's rating scale on postoperative sternoclavicular joint, 8 cases achieved excellent outcomes with an average score of 13.88, and the rest case achieved a good outcome with the score of 12. Anatomical reduction was obtained in all cases. There were no such postoperative complications as severe infection, injury to blood vessel and nerve, failure of fixation, etc. Patients were all satisfied with the anatomical reduction and functional recovery. The technique of K-wire and tension band wire fixation is safe, simple, effective, less invasive and has been successfully used in orthopedic surgery. It is effective in treating sternoclavicular joint dislocation though it has some disadvantages.

Outcomes After Arthroscopic Bankart Repair in Adolescent Athletes Participating in Collision and Contact Sports

PubMed Central

Saper, Michael G.; Milchteim, Charles; Zondervan, Robert L.; Andrews, James R.; Ostrander, Roger V.

2017-01-01

Background: Literature on arthroscopic stabilization in adolescent patients participating in collision and contact sports is limited, as most studies include adolescents within a larger sample group comprised primarily of adults. Purpose: To review the outcomes of arthroscopic Bankart repair for anterior shoulder instability in an adolescent population participating in collision and contact sports. Study Design: Case series; Level of evidence, 4. Methods: This retrospective review included 39 shoulders in 37 adolescent (≤19 years) athletes who underwent primary arthroscopic Bankart repair using suture anchors with at least 2-year follow-up. All patients had a history of trauma to their shoulder resulting in an anterior dislocation. Outcome measures included patient satisfaction, the visual analog scale (VAS) for pain, American Shoulder and Elbow Surgeons (ASES) score, and Rowe score. Recurrence of dislocation and return to sporting activity were also assessed. Results: The mean age at the time of surgery was 16.9 years (range, 15-19 years), and the mean follow-up was 6.3 years (range, 4.3-10.0 years); 58.6% of patients participated in collision sports. Time to surgery after the initial dislocation episode was 9.2 months (range, 0.5-36.2 months). Four shoulders (10.3%) had dislocation events postoperatively. The majority (78.1%) of patients returned to sports at the same level of competition. Mean VAS was 0.49 ± 1.0, and the mean ASES and Rowe scores were 92.8 ± 12.6 and 85.0 ± 24.2, respectively. Univariate analyses demonstrated that subjective functional outcomes were negatively correlated with recurrence (ASES, P = .005; Rowe, P = .001) and failure to return to sport (ASES, P = .016; Rowe, P = .004). Independent variables shown to have no significant relationship to functional outcomes included age, follow-up, number of preoperative dislocations, time to surgery, sport classification, competition level, tear extent, number of anchors, concurrent Hill-Sachs lesion, and repair of a superior labral anterior-posterior (SLAP) lesion. Conclusion: Arthroscopic Bankart repair is an effective surgical option for traumatic shoulder instability in adolescents participating in collision and contact sports. At a minimum 4-year follow-up, arthroscopic Bankart repair effectively restored stability in 90% of cases; 80% returned to their preinjury level of sport. PMID:28451607

A Case of Acromioclavicular Joint Dislocation Associated with Coracoid Process Fracture.

PubMed

Nakamura, Yosuke; Gotoh, Masafumi; Mitsui, Yasuhiro; Shirachi, Isao; Yoshikawa, Eiichiro; Uryu, Takuya; Murakami, Hidetaka; Okawa, Takahiro; Higuchi, Fujio; Shiba, Naoto

2015-01-01

Rupture of any two or more parts of the superior shoulder suspensory complex (SSSC) including the distal clavicle, acromion, coracoid process, glenoid cavity of the scapula, acromioclavicular ligament, and coracoclavicular ligament is associated with shoulder girdle instability and is an indication for surgery. Here we report a case of acromioclavicular joint dislocation associated with coracoid process fracture. A 48-year-old man sustained a hard blow to the left shoulder from a fall, and simple radiography detected a coracoid process fracture and acromioclavicular joint dislocation. The injury consisted of a rupture of two parts of the SSSC. For the coracoid process fracture, osteosynthesis was performed using hollow cancellous bone screws. For the acromioclavicular joint dislocation, hook plate fixation and the modified Neviaser's procedure were performed. The bone healed well 5 months after surgery, at which time the screws were removed. At 18 months after initial surgery, the coracoid process fracture had healed with a 10% rate of dislocation on radiography, and the patient currently has no problem performing daily activities, no range of motion limitations, and a Japanese Orthopaedic Association scale score of 93.

Sideline Coverage

PubMed Central

Gould, Sara J.; Cardone, Dennis A.; Munyak, John; Underwood, Philipp J.; Gould, Stephen A.

2014-01-01

Context: Sidelines coverage presents unique challenges in the evaluation of injured athletes. Health care providers may be confronted with the question of when to obtain radiographs following an injury. Given that most sidelines coverage occurs outside the elite level, radiographs are not readily available at the time of injury, and the decision of when to send a player for radiographs must be made based on physical examination. Clinical tools have been developed to aid in identifying injuries that are likely to result in radiographically important fractures or dislocations. Evidence Acquisition: A search for the keywords x-ray and decision rule along with the anatomic locations shoulder, elbow, wrist, knee, and ankle was performed using the PubMed database. No limits were set regarding year of publication. We selected meta-analyses, randomized controlled trials, and survey results. Our selection focused on the largest, most well-studied published reports. We also attempted to include studies that reported the application of the rules to the field of sports medicine. Study Design: Retrospective literature review. Level of Evidence: Level 4. Results: The Ottawa Foot and Ankle Rules have been validated and implemented and are appropriate for use in both pediatric and adult populations. The Ottawa Knee Rules have been widely studied, validated, and accepted for evaluation of knee injuries. There are promising studies of decision rules for clinically important fractures of the wrist, but these studies have not been validated. The elbow has been evaluated with good outcomes via the elbow extension test, which has been validated in both single and multicenter studies. Currently, there are no reliable clinical decision tools for traumatic sports injuries to the shoulder to aid in the decision of when to obtain radiographs. Conclusion: Clinical decision tools have been developed to aid in the diagnosis and management of injuries commonly sustained during sporting events. Tools that have been appropriately validated in populations outside the initial study population can assist sports medicine physicians in the decision of when to get radiographs from the sidelines. PMID:24790698

Sideline coverage: when to get radiographs? A review of clinical decision tools.

PubMed

Gould, Sara J; Cardone, Dennis A; Munyak, John; Underwood, Philipp J; Gould, Stephen A

2014-05-01

Sidelines coverage presents unique challenges in the evaluation of injured athletes. Health care providers may be confronted with the question of when to obtain radiographs following an injury. Given that most sidelines coverage occurs outside the elite level, radiographs are not readily available at the time of injury, and the decision of when to send a player for radiographs must be made based on physical examination. Clinical tools have been developed to aid in identifying injuries that are likely to result in radiographically important fractures or dislocations. A search for the keywords x-ray and decision rule along with the anatomic locations shoulder, elbow, wrist, knee, and ankle was performed using the PubMed database. No limits were set regarding year of publication. We selected meta-analyses, randomized controlled trials, and survey results. Our selection focused on the largest, most well-studied published reports. We also attempted to include studies that reported the application of the rules to the field of sports medicine. Retrospective literature review. Level 4. The Ottawa Foot and Ankle Rules have been validated and implemented and are appropriate for use in both pediatric and adult populations. The Ottawa Knee Rules have been widely studied, validated, and accepted for evaluation of knee injuries. There are promising studies of decision rules for clinically important fractures of the wrist, but these studies have not been validated. The elbow has been evaluated with good outcomes via the elbow extension test, which has been validated in both single and multicenter studies. Currently, there are no reliable clinical decision tools for traumatic sports injuries to the shoulder to aid in the decision of when to obtain radiographs. Clinical decision tools have been developed to aid in the diagnosis and management of injuries commonly sustained during sporting events. Tools that have been appropriately validated in populations outside the initial study population can assist sports medicine physicians in the decision of when to get radiographs from the sidelines.

From Mild to WildLV14378 Fluctuations in Crystal Plasticity

NASA Astrophysics Data System (ADS)

Weiss, J.; Rhouma, W. Ben; Richeton, T.; Dechanel, S.; Louchet, F.; Truskinovsky, L.

2015-03-01

Macroscopic crystal plasticity is classically viewed as an outcome of uncorrelated dislocation motions producing Gaussian fluctuations. An apparently conflicting picture emerged in recent years emphasizing highly correlated dislocation dynamics characterized by power-law distributed fluctuations. We use acoustic emission measurements in crystals with different symmetries to show that intermittent and continuous visions of plastic flow are not incompatible. We demonstrate the existence of crossover regimes where strongly intermittent events coexist with a Gaussian quasiequilibrium background and propose a simple theoretical framework compatible with these observations.

Current evidence for effectiveness of interventions for cubital tunnel syndrome, radial tunnel syndrome, instability, or bursitis of the elbow: a systematic review.

PubMed

Rinkel, Willem D; Schreuders, Ton A R; Koes, Bart W; Huisstede, Bionka M A

2013-12-01

To provide an evidence-based overview of the effectiveness of interventions for 4 nontraumatic painful disorders sharing the anatomic region of the elbow: cubital tunnel syndrome, radial tunnel syndrome, elbow instability, and olecranon bursitis. The Cochrane Library, PubMed, Embase, PEDro, and CINAHL were searched to identify relevant reviews and randomized clinical trials (RCTs). Two reviewers independently extracted data and assessed the quality of the methodology. A best-evidence synthesis was used to summarize the results. One systematic review and 6 RCTs were included. For the surgical treatment of cubital tunnel syndrome (1 review, 3 RCTs), comparing simple decompression with anterior ulnar nerve transposition, no evidence was found in favor of either one of these. Limited evidence was found in favor of medial epicondylectomy versus anterior transposition and for early postoperative therapy versus immobilization. No evidence was found for the effect of local steroid injection in addition to splinting. No RCTs were found for radial tunnel syndrome. For olecranon bursitis (1 RCT), limited evidence for effectiveness was found for methylprednisolone acetate injection plus naproxen. Concerning elbow instability, including 2 RCTs, one showed that nonsurgical treatment resulted in similar results compared with surgery, whereas the other found limited evidence for the effectiveness in favor of early mobilization versus 3 weeks of immobilization after surgery. In this review no, or at best, limited evidence was found for the effectiveness of nonsurgical and surgical interventions to treat painful cubital tunnel syndrome, radial tunnel syndrome, elbow instability, or olecranon bursitis. Well-designed and well-conducted RCTs are clearly needed in this field.

Latarjet Procedure for Anterior Shoulder Instability Due to Tramadol-Induced Seizures: A Multicenter Study.

PubMed

Khater, Ahmad Hany; Sobhy, Mohamed H; Said, Hatem G; Kandil, Ahmed; Reda, Walid; Seifeldin, Ahmed Fouad; Moustafa, Ramez; Elassal, Maher A; Kamel, Ezzat M

2016-04-01

Seizures, commonly due to epilepsy, are known to cause shoulder instability. Tramadol addiction has recently been found to induce seizures in patients who exceed the recommended dose. Because of the easy accessibility and low cost of tramadol, an increasingly alarming phenomenon of tramadol abuse has been demonstrated in recent years. The purpose of this multicenter study was to investigate shoulder instability resulting from tramadol-induced seizure (TIS) as well as to recommended management for such shoulder instability. The hypothesis was that TIS leads to anterior shoulder dislocations with major bony defects, which favors bony reconstructive procedures as a suitable method of treatment. Case series; Level of evidence, 4. This prospective case series study was conducted on 73 patients (78 shoulders) who presented with anterior shoulder dislocations and a clear history of tramadol abuse. The mean age of the patients was 26.8 years, and the mean number of dislocations was 14. The mean duration of addiction was 17 months, with a mean dose of 752 mg of tramadol hydrochloride per day. Glenoid and humeral bone loss ranged from 15% to 35% and from 15% to 40%, respectively. The mean follow-up period was 28 months. All patients underwent an open Latarjet procedure. Postoperative mean Rowe score and American Shoulder and Elbow Surgeons score at final follow-up (24 months) improved significantly from 20 to 84 and from 44 to 91, respectively (P < .05). The patient satisfaction rate reached 95%, and the mean period of return to work was 12.8 weeks. Five patients (9%) had postoperative seizures due to relapse of the tramadol abuse, but only 3 patients (5%) had redislocations with nonunion or breakage of the graft or hardware. Tramadol addiction has evolved as an important cause of seizures that can result in shoulder dislocation. Anterior shoulder instability with TIS occurs mainly with higher levels of addiction and results in significant humeral and/or glenoid bone defects. The Latarjet procedure is recommended for these patients, after control of addiction, and provides 95% satisfaction at midterm follow-up. © 2016 The Author(s).

Elastic strain relaxation in interfacial dislocation patterns: I. A parametric energy-based framework

NASA Astrophysics Data System (ADS)

Vattré, A.

2017-08-01

A parametric energy-based framework is developed to describe the elastic strain relaxation of interface dislocations. By means of the Stroh sextic formalism with a Fourier series technique, the proposed approach couples the classical anisotropic elasticity theory with surface/interface stress and elasticity properties in heterogeneous interface-dominated materials. For any semicoherent interface of interest, the strain energy landscape is computed using the persistent elastic fields produced by infinitely periodic hexagonal-shaped dislocation configurations with planar three-fold nodes. A finite element based procedure combined with the conjugate gradient and nudged elastic band methods is applied to determine the minimum-energy paths for which the pre-computed energy landscapes yield to elastically favorable dislocation reactions. Several applications on the Au/Cu heterosystems are given. The simple and limiting case of a single set of infinitely periodic dislocations is introduced to determine exact closed-form expressions for stresses. The second limiting case of the pure (010) Au/Cu heterophase interfaces containing two crossing sets of straight dislocations investigates the effects due to the non-classical boundary conditions on the stress distributions, including separate and appropriate constitutive relations at semicoherent interfaces and free surfaces. Using the quantized Frank-Bilby equation, it is shown that the elastic strain landscape exhibits intrinsic dislocation configurations for which the junction formation is energetically unfavorable. On the other hand, the mismatched (111) Au/Cu system gives rise to the existence of a minimum-energy path where the fully strain-relaxed equilibrium and non-regular intrinsic hexagonal-shaped dislocation rearrangement is accompanied by a significant removal of the short-range elastic energy.

Generation of phase edge singularities by coplanar three-beam interference and their detection.

PubMed

Patorski, Krzysztof; Sluzewski, Lukasz; Trusiak, Maciej; Pokorski, Krzysztof

2017-02-06

In recent years singular optics has gained considerable attention in science and technology. Up to now optical vortices (phase point dislocations) have been of main interest. This paper presents the first general analysis of formation of phase edge singularities by coplanar three-beam interference. They can be generated, for example, by three-slit interference or self-imaging in the Fresnel diffraction field of a sinusoidal grating. We derive a general condition for the ratio of amplitudes of interfering beams resulting in phase edge dislocations, lateral separation of dislocations depends on this ratio as well. Analytically derived properties are corroborated by numerical and experimental studies. We develop a simple, robust, common path optical self-imaging configuration aided by a coherent tilted reference wave and spatial filtering. Finally, we propose an automatic fringe pattern analysis technique for detecting phase edge dislocations, based on the continuous wavelet transform. Presented studies open new possibilities for developing grating based sensing techniques for precision metrology of very small phase differences.

Dislocation filtering in GaN nanostructures.

PubMed

Colby, Robert; Liang, Zhiwen; Wildeson, Isaac H; Ewoldt, David A; Sands, Timothy D; García, R Edwin; Stach, Eric A

2010-05-12

Dislocation filtering in GaN by selective area growth through a nanoporous template is examined both by transmission electron microscopy and numerical modeling. These nanorods grow epitaxially from the (0001)-oriented GaN underlayer through the approximately 100 nm thick template and naturally terminate with hexagonal pyramid-shaped caps. It is demonstrated that for a certain window of geometric parameters a threading dislocation growing within a GaN nanorod is likely to be excluded by the strong image forces of the nearby free surfaces. Approximately 3000 nanorods were examined in cross-section, including growth through 50 and 80 nm diameter pores. The very few threading dislocations not filtered by the template turn toward a free surface within the nanorod, exiting less than 50 nm past the base of the template. The potential active region for light-emitting diode devices based on these nanorods would have been entirely free of threading dislocations for all samples examined. A greater than 2 orders of magnitude reduction in threading dislocation density can be surmised from a data set of this size. A finite element-based implementation of the eigenstrain model was employed to corroborate the experimentally observed data and examine a larger range of potential nanorod geometries, providing a simple map of the different regimes of dislocation filtering for this class of GaN nanorods. These results indicate that nanostructured semiconductor materials are effective at eliminating deleterious extended defects, as necessary to enhance the optoelectronic performance and device lifetimes compared to conventional planar heterostructures.

Vortex breakdown in simple pipe bends

NASA Astrophysics Data System (ADS)

Ault, Jesse; Shin, Sangwoo; Stone, Howard

2016-11-01

Pipe bends and elbows are one of the most common fluid mechanics elements that exists. However, despite their ubiquity and the extensive amount of research related to these common, simple geometries, unexpected complexities still remain. We show that for a range of geometries and flow conditions, these simple flows experience unexpected fluid dynamical bifurcations resembling the bubble-type vortex breakdown phenomenon. Specifically, we show with simulations and experiments that recirculation zones develop within the bends under certain conditions. As a consequence, fluid and particles can remain trapped within these structures for unexpectedly-long time scales. We also present simple techniques to mitigate this recirculation effect which can potentially have impact across industries ranging from biomedical and chemical processing to food and health sciences.

Proximal humeral fractures: the role of calcium sulphate augmentation and extended deltoid splitting approach in internal fixation using locking plates.

PubMed

Somasundaram, K; Huber, C P; Babu, V; Zadeh, H

2013-04-01

The aim of our study is to analyse the results of our surgical technique for the treatment of proximal humeral fractures and fracture dislocations using locking plates in conjunction with calcium sulphate bone-substitute augmentation and tuberosity repair using high-strength sutures. We used the extended deltoid-splitting approach for fracture patterns involving displacement of both lesser and greater tuberosities and for fracture-dislocations. Optimal surgical management of proximal humeral fractures remains controversial. Locking plates have become a popular method of fixation. However, failure of fixation may occur if they are used as the sole method of fixation in comminuted fractures, especially in osteopenic bone. We retrospectively analysed 22 proximal humeral fractures in 21 patients; 10 were male and 11 female with an average age of 64.6 years (range 37-77). Average follow-up was 24 months. Eleven of these fractures were exposed by the extended deltoid-splitting approach. Fractures were classified according to Neer and Hertel systems. Preoperative radiographs and computed tomography (CT) scans in three- and four-part fractures were done to assess the displacement and medial calcar length for predicting the humeral head vascularity. According to the Neer classification, there were five two-part, six three-part, five four-part fractures and six fracture-dislocations (two anterior and four posterior). Results were assessed clinically with disabilities of the arm, shoulder and hand (DASH) scores, modified Constant and Murley scores and serial postoperative radiographs. The mean DASH score was 16.18 and the modified Constant and Murley score was 64.04 at the last follow-up. Eighteen out of twenty-two cases achieved good clinical outcome. All the fractures united with no evidence of infection, failure of fixation, malunion, tuberosity failure, avascular necrosis or adverse reaction to calcium sulphate bone substitute. There was no evidence of axillary nerve injury. Four patients had a longer recovery period due to stiffness, associated wrist fracture and elbow dislocation. The CaSO4 bone substitute was replaced by normal appearing trabecular bone texture at an average of 6 months in all patients. In our experience, we have found the use of locking plates, calcium sulphate bone substitute and tuberosity repair with high-strength sutures to be a safe and reliable method of internal fixation for complex proximal humeral fractures and fracture-dislocations. Furthermore, we have also found the use of the extended deltoid-splitting approach to be safe and to provide excellent exposure facilitating accurate reduction for fixation of the fracture patterns involving displacement of both lesser and greater tuberosities and for fracture-dislocations. Copyright © 2012 Elsevier Ltd. All rights reserved.

Preferences of orthopedic surgeons for treating midshaft clavicle fracture in adults

PubMed Central

de Oliveira, Adilson Sanches; Roberto, Bruno Braga; Lenza, Mario; Pintan, Guilherme Figueiredo; Ejnisman, Benno; Schor, Breno; Carrera, Eduardo da Frota; Murachovsky, Joel

2017-01-01

ABSTRACT Objective To determine the current clinical practice in Latin America for treating midshaft clavicle fractures, including surgical and non-surgical approaches. Methods A cross-sectional study using a descriptive questionnaire. Shoulder and elbow surgeons from the Brazilian Society of Shoulder and Elbow Surgery and from the Latin American Society of Shoulder and Elbow were contacted and asked to complete a short questionnaire (SurveyMonkey®) on the management of midshaft fractures of the clavicle. Incomplete or inconsistent answers were excluded. Results The type of radiographic classification preferably used was related to description of fracture morphology, according to 41% of participants. Allman classification ranked second and was used by 24.1% of participants. As to indications for surgical treatment, only the indications with shortening and imminence of skin exposure were statistically significant. Conservative treatment was chosen in cortical contact. Regarding immobilization method, the simple sling was preferred, and treatment lasted from 4 to 6 weeks. Although the result was not statistically significant, the blocked plate was the preferred option in surgical cases. Conclusion The treatment of midshaft clavicle fractures in Latin America is in accordance with the current literature. PMID:29091151

Modular one-to-many clutchable actuator for a soft elbow exosuit.

PubMed

Canesi, M; Xiloyannis, M; Ajoudani, A; Biechi, A; Masia, L

2017-07-01

Exoskeletons have been developed for a wide range of applications, from the military to the medical field, with the aim of augmenting human performance or compensating for neuromuscular deficiencies. However, to empower the high number of degrees of freedom of the human body, they often employ a high number of motors, increasing the size, weight and power consumption of the system. We hereby present an actuation strategy to empower our elbow exosuit that adopts a single motor to drive multiple, independently actuated, degrees of freedom. This paradigm, known as One-to-many, is achieved using a modular design where each module comprises a clutchable mechanism that allows to convert a single directional motion from the prime mover to a selectable bidirectional output. Moreover, the mechanism has a locking feature that enables the wearer of the exoskeleton to hold a static load with a minimal power consumption. We present a simple controller for the clutchable unit based on a finite-state machine model, and evaluate its performance for varying input velocities. The system is shown to have a bandwidth of 1.5 Hz, sufficient for daily elbow movements, whilst retaining a compact design.

DEFORMATION PROCESSES IN MATERIALS. Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Washburn, J.; Parker, E.R.; Tinder, R.F.

1962-08-01

It was found that irreversible plastic deformation occurs in polycrystaliine specimens of zinc, copper and its dilute alloys, and aluminum at room temperature, beginning at stresses indetectably above zero applied stress. Neither Frank-Read source generation nor simple bowing of dislocations between fixed nodes can explain the irreversible plastic behavior observed at small stresses in the metals studied. More extensive rearrangements of the dislocation substructure that probably involve glide of nodes and formation of new nodes seem to be required. Prestrained specimens of copper and its dilute alloys often exhibited bursts of plastic deformation which could possibly be due to cooperativemore » rearrangement of the dislocation substructure in one or a few grains. The introduction, by particle bombardment, of new lengths of dislocations into the gage section surface of specimens of copper and its dilute alloys produced extensive irreversible plastic flow beginning at stresses indetectably above zero applied stress. The effect of prestraln on the shape of the loading and unloading curves for zinc shows that dislocation rearrangements that cause forward and reverse strain can occur simultaneously. The net strain rate can be the algebraic sum of the strain recovery rate and the forward creep rate. The present quantitative theories of the Peierls-Nabarro stress are insufficient to permit an estimate of its magnitude from the results of this investigation. In dilute copper alloys containing up to 0.1 at.% impurity, there were many dislocations in the grown-in networks that were not locked by segregation of the foreign atoms. The study of creep behavior over a range of temperatures and at the same strain sensitivity used in these experiments combined with dislocation etch pit observations of dislocation substructure appears to be a particularly fruitful field for further investigation. (auth)« less

Does arthroscopic rotator cuff repair improve patients' activity levels?

PubMed

Baumgarten, Keith M; Chang, Peter S; Dannenbring, Tasha M; Foley, Elaine K

2018-06-04

Rotator cuff repair decreases pain, improves range of motion, and increases strength. Whether these improvements translate to an improvement in a patient's activity level postoperatively remains unknown. The Shoulder Activity Level is a valid and reliable outcomes survey that can be used to measure a patient's shoulder-specific activity level. Currently, there are no studies that examine the effect of rotator cuff repair on shoulder activity level. Preoperative patient-determined outcomes scores collected prospectively on patients undergoing rotator cuff repair were compared with postoperative scores at a minimum of 2 years. These scores included the Shoulder Activity Level, Western Ontario Rotator Cuff Index, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, Single Assessment Numeric Evaluation, and simple shoulder test. Inclusion criteria were patients undergoing arthroscopic rotator cuff repair. Included were 281 shoulders from 273 patients with a mean follow-up of 3.7 years. The postoperative median Western Ontario Rotator Cuff Index (42 vs. 94), American Shoulder and Elbow Surgeons (41 vs. 95), Single Assessment Numeric Evaluation (30 vs. 95), and simple shoulder test (4 vs. 11) scores were statistically significantly improved compared with preoperative scores (P < .0001). The postoperative median Shoulder Activity Level score decreased compared with the preoperative score (12 vs. 11; P < .0001). Patients reported a statistically significant deterioration of their Shoulder Activity Level score after rotator cuff repair compared with their preoperative scores, although disease-specific and joint-specific quality of life scores all had statistically significantly improvement. This study suggests that patients generally have (1) significant improvements in their quality of life and (2) small deteriorations in activity level after arthroscopic rotator cuff repair. Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Nirschl surgical technique for concomitant lateral and medial elbow tendinosis: a retrospective review of 53 elbows with a mean follow-up of 11.7 years.

PubMed

Schipper, Oliver N; Dunn, Jonathan H; Ochiai, Derek H; Donovan, J Skye; Nirschl, Robert P

2011-05-01

Combined lateral elbow tendinosis (tennis elbow) and medial elbow tendinosis (golfer's elbow) can be a disabling condition that, if unresponsive to nonoperative treatments, may be effectively treated surgically. The authors are not aware of any study that reports the outcome of a combined operation for lateral and medial elbow tendinosis (country club elbow) performed in the same operative setting. Combined surgical treatment of country club elbow in the same operative setting has similar outcomes to those seen in the literature for single operative procedures. Case series; Level of evidence 4. Outcome measurements included the Numeric Pain Intensity Scale, the Nirschl tennis elbow scoring system, and the American Shoulder and Elbow Surgeons elbow form. Forty-eight patients (53 clinical elbows) were available by telephone, with a minimum time to follow-up of 5 years (range, 5-19 years; mean, 11.7 years). The average Nirschl tennis elbow score improved from 16.7 preoperatively to 70.8 postoperatively (P < .01). The average American Shoulder and Elbow Surgeons elbow score improved from 45.2 to 90.4 (P < .01). The Numeric Pain Intensity Scale score improved from 8.8 to 1.7 (P < .01). By the criteria of the Nirschl tennis elbow score, results were rated excellent in 38 elbows, good in 7 elbows, fair in 5 elbows, and poor in 3 elbows, with 85% (45 of 53) good to excellent results. Patient satisfaction with the surgery averaged 8.7 out of 10. Of the 46 patients who played sports, 44 (96%) reported returning to their sports. When nonoperative treatment of lateral and medial elbow tendinosis fails, combined surgical intervention via the Nirschl operative techniques for country club elbow is highly effective, with results similar to those of single-sided intervention.

A clinical and ultrasonographic study of risk factors for elbow injury in young baseball players.

PubMed

Tajika, T; Kobayashi, T; Yamamoto, A; Kaneko, T; Shitara, H; Shimoyama, D; Iizuka, Y; Okamura, K; Yonemoto, Y; Warita, T; Ohsawa, T; Nakajima, I; Iizuka, H; Takagishi, K

2016-04-01

To determine the risk factors for elbow injury and its association with glenohumeral internal rotation deficit among young baseball players. 229 baseball players aged 9 to 14 (mean, 11) years completed a self-administered questionnaire with items related to years of playing baseball, hours of training per weekday, days of training per week, and past and present experience of elbow pain. Two orthopaedic surgeons measured the range of motion of both shoulders and elbows. Another 2 orthopaedic surgeons performed ultrasonography to detect any elbow abnormality such as fragmentation of the medial epicondylar apophysis and osteochondritis dissecans of the capitellum. Using univariate and multivariable analyses, participants with or without elbow abnormality were compared to determine the risk factors for elbow abnormality. Elbow abnormality was detected in 100 of the participants and comprised osteochondritis dissecans of the capitellum (n=18) and fragmentation of the medial epicondylar apophysis (n=82). Elbow abnormality was associated with being a pitcher, past and present experience of elbow pain, loss of elbow extension, and the side-to-side internal rotation difference. The 100 participants with elbow abnormality were stratified into symptomatic (n=57) or asymptomatic (n=43) of elbow pain. Those with elbow abnormality and elbow pain was associated with being a pitcher. Being a pitcher was a risk factor for both elbow abnormality and elbow pain. Nonetheless, 43% of baseball players with elbow abnormality were asymptomatic. The use of ultrasonography was effective in detecting elbow abnormality and enabling early treatment.

The barrier to misfit dislocation glide in continuous, strained, epitaxial layers on patterned substrates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Watson, G.P.; Ast, D.G.; Anderson, T.J.

1993-09-01

In a previous report [G. P. Watson, D. G. Ast, T. J. Anderson, and Y. Hayakawa, Appl. Phys. Lett. [bold 58], 2517 (1991)] we demonstrated that the motion of misfit dislocations in InGaAs, grown by organometallic vapor phase epitaxy on patterned GaAs substrates, can be impeded even if the strained epitaxial layer is continuous. Trenches etched into GaAs before growth are known to act as a barrier to misfit dislocation propagation [E. A. Fitzgerald, G. P. Watson, R. E. Proano, D. G. Ast, P. D. Kirchner, G. D. Pettit, and J. M. Woodall, J. Appl. Phys. [bold 65], 2220 (1989)]more » when those trenches create discontinuities in the epitaxial layers; but even shallow trenches, with continuous strained layers following the surface features, can act as barriers. By considering the strain energy required to change the length of the dislocation glide segments that stretch from the interface to the free surface, a simple model is developed that explains the major features of the unique blocking action observed at the trench edges. The trench wall angle is found to be an important parameter in determining whether or not a trench will block dislocation glide. The predicted blocking angles are consistent with observations made on continuous 300 and 600 nm thick In[sub 0.04]Ga[sub 0.96]As films on patterned GaAs. Based on the model, a structure is proposed that may be used as a filter to yield misfit dislocations with identical Burgers vectors or dislocations which slip in only one glide plane.« less

Phyllotactic transformations as plastic deformations of tubular crystals with defects

NASA Astrophysics Data System (ADS)

Beller, Daniel; Nelson, David

Tubular crystals are 2D lattices in cylindrical topologies, which could be realized as assemblies of colloidal particles, and occur naturally in biological microtubules and in single-walled carbon nanotubes. Their geometry can be understood in the language of phyllotaxis borrowed from botany. We study the mechanics of plastic deformations in tubular crystals in response to tensile stress, as mediated by the formation and separation of dislocation pairs in a triangular lattice. Dislocation motion allows the growth of one phyllotactic arrangement at the expense of another, offering a low-energy, stepwise mode of plastic deformation in response to external stresses. Through theory and simulation, we examine how the tube's radius and helicity affects, and is in turn altered by, dislocation glide. The crystal's bending modulus is found to produce simple but important corrections to the tube's deformation mechanics.

The Effects of Elbow Bracing on Medial Elbow Joint Space Gapping Associated With Repetitive Throwing in High School Baseball Players

PubMed Central

Hattori, Hiroshi; Akasaka, Kiyokazu; Otsudo, Takahiro; Takei, Keiichi; Yamamoto, Mitsuru

2017-01-01

Background: Throwing athletes risk medial elbow injury from extreme valgus stress generated across the medial elbow during throwing. Braces have been developed to protect the elbow joint; however, no previous study has investigated the effects of elbow bracing on medial elbow joint space gapping associated with repetitive throwing. Hypothesis/Purpose: The purpose of this study was to investigate the effects of elbow bracing on medial elbow joint space gapping during repetitive throwing. Our hypothesis was that an elbow brace may reduce mechanical stress on the elbow by reducing medial elbow joint space gapping. Study Design: Controlled laboratory study. Methods: Twenty-five high school baseball players participated in this study. Each subject pitched 100 times under 2 conditions: control (without elbow brace) and elbow brace. The ulnohumeral joint space was measured ultrasonically before pitching and after every block of 20 pitches. Measurement of the ulnohumeral joint space was carried out using ultrasound with the forearm hanging by the side. Two-way repeated-measures analysis of variance and post hoc tests were used to compare ulnohumeral joint space with repeated pitching and between the elbow brace and control conditions. Results: In the control condition, ulnohumeral joint space after 60 pitches was significantly greater than that before pitching (P < .01). In contrast, in the elbow brace condition, ulnohumeral joint space was not significantly different after repeated pitching. When comparing these 2 conditions, ulnohumeral joint space in the control condition was significantly greater than that in the elbow brace condition after 60 pitches (P < .01). Conclusion: An elbow brace has the effect of preventing medial elbow joint space gapping with repeated throwing when determined ultrasonically by measuring the ulnohumeral joint space under gravity load. Clinical Relevance: An elbow brace worn during baseball pitching practice may help reduce mechanical stress on the elbow by reducing medial elbow joint space gapping. PMID:28451622

The Effects of Elbow Bracing on Medial Elbow Joint Space Gapping Associated With Repetitive Throwing in High School Baseball Players.

PubMed

Hattori, Hiroshi; Akasaka, Kiyokazu; Otsudo, Takahiro; Takei, Keiichi; Yamamoto, Mitsuru

2017-04-01

Throwing athletes risk medial elbow injury from extreme valgus stress generated across the medial elbow during throwing. Braces have been developed to protect the elbow joint; however, no previous study has investigated the effects of elbow bracing on medial elbow joint space gapping associated with repetitive throwing. The purpose of this study was to investigate the effects of elbow bracing on medial elbow joint space gapping during repetitive throwing. Our hypothesis was that an elbow brace may reduce mechanical stress on the elbow by reducing medial elbow joint space gapping. Controlled laboratory study. Twenty-five high school baseball players participated in this study. Each subject pitched 100 times under 2 conditions: control (without elbow brace) and elbow brace. The ulnohumeral joint space was measured ultrasonically before pitching and after every block of 20 pitches. Measurement of the ulnohumeral joint space was carried out using ultrasound with the forearm hanging by the side. Two-way repeated-measures analysis of variance and post hoc tests were used to compare ulnohumeral joint space with repeated pitching and between the elbow brace and control conditions. In the control condition, ulnohumeral joint space after 60 pitches was significantly greater than that before pitching ( P < .01). In contrast, in the elbow brace condition, ulnohumeral joint space was not significantly different after repeated pitching. When comparing these 2 conditions, ulnohumeral joint space in the control condition was significantly greater than that in the elbow brace condition after 60 pitches ( P < .01). An elbow brace has the effect of preventing medial elbow joint space gapping with repeated throwing when determined ultrasonically by measuring the ulnohumeral joint space under gravity load. An elbow brace worn during baseball pitching practice may help reduce mechanical stress on the elbow by reducing medial elbow joint space gapping.

Modeling of dislocation channel width evolution in irradiated metals

DOE PAGES

Doyle, Peter J.; Benensky, Kelsa M.; Zinkle, Steven J.

2017-11-08

Defect-free dislocation channel formation has been reported to promote plastic instability during tensile testing via localized plastic flow, leading to a distinct loss of ductility and strain hardening in many low-temperature irradiated materials. In order to study the underlying mechanisms governing dislocation channel width and formation, the channel formation process is modeled via a simple stochastic dislocation-jog process dependent upon grain size, defect cluster density, and defect size. Dislocations traverse a field of defect clusters and jog stochastically upon defect interaction, forming channels of low defect-density. And based upon prior molecular dynamics (MD) simulations and in-situ experimental transmission electron microscopymore » (TEM) observations, each dislocation encounter with a dislocation loop or stacking fault tetrahedron (SFT) is assumed to cause complete absorption of the defect cluster, prompting the dislocation to jog up or down by a distance equal to half the defect cluster diameter. Channels are predicted to form rapidly and are comparable to reported TEM measurements for many materials. Predicted channel widths are found to be most strongly dependent on mean defect size and correlated well with a power law dependence on defect diameter and density, and distance from the dislocation source. Due to the dependence of modeled channel width on defect diameter and density, maximum channel width is predicted to slowly increase as accumulated dose increases. The relatively weak predicted dependence of channel formation width with distance, in accordance with a diffusion analogy, implies that after only a few microns from the source, most channels observed via TEM analyses may not appear to vary with distance because of limitations in the field-of-view to a few microns. Furthermore, examinations of the effect of the so-called “source-broadening” mechanism of channel formation showed that its effect is simply to add a minimum thickness to the channel without affecting channel dependence on the given parameters.« less

Modeling of dislocation channel width evolution in irradiated metals

NASA Astrophysics Data System (ADS)

Doyle, Peter J.; Benensky, Kelsa M.; Zinkle, Steven J.

2018-02-01

Defect-free dislocation channel formation has been reported to promote plastic instability during tensile testing via localized plastic flow, leading to a distinct loss of ductility and strain hardening in many low-temperature irradiated materials. In order to study the underlying mechanisms governing dislocation channel width and formation, the channel formation process is modeled via a simple stochastic dislocation-jog process dependent upon grain size, defect cluster density, and defect size. Dislocations traverse a field of defect clusters and jog stochastically upon defect interaction, forming channels of low defect-density. Based upon prior molecular dynamics (MD) simulations and in-situ experimental transmission electron microscopy (TEM) observations, each dislocation encounter with a dislocation loop or stacking fault tetrahedron (SFT) is assumed to cause complete absorption of the defect cluster, prompting the dislocation to jog up or down by a distance equal to half the defect cluster diameter. Channels are predicted to form rapidly and are comparable to reported TEM measurements for many materials. Predicted channel widths are found to be most strongly dependent on mean defect size and correlated well with a power law dependence on defect diameter and density, and distance from the dislocation source. Due to the dependence of modeled channel width on defect diameter and density, maximum channel width is predicted to slowly increase as accumulated dose increases. The relatively weak predicted dependence of channel formation width with distance, in accordance with a diffusion analogy, implies that after only a few microns from the source, most channels observed via TEM analyses may not appear to vary with distance because of limitations in the field-of-view to a few microns. Further, examinations of the effect of the so-called "source-broadening" mechanism of channel formation showed that its effect is simply to add a minimum thickness to the channel without affecting channel dependence on the given parameters.

Modeling of dislocation channel width evolution in irradiated metals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doyle, Peter J.; Benensky, Kelsa M.; Zinkle, Steven J.

Defect-free dislocation channel formation has been reported to promote plastic instability during tensile testing via localized plastic flow, leading to a distinct loss of ductility and strain hardening in many low-temperature irradiated materials. In order to study the underlying mechanisms governing dislocation channel width and formation, the channel formation process is modeled via a simple stochastic dislocation-jog process dependent upon grain size, defect cluster density, and defect size. Dislocations traverse a field of defect clusters and jog stochastically upon defect interaction, forming channels of low defect-density. And based upon prior molecular dynamics (MD) simulations and in-situ experimental transmission electron microscopymore » (TEM) observations, each dislocation encounter with a dislocation loop or stacking fault tetrahedron (SFT) is assumed to cause complete absorption of the defect cluster, prompting the dislocation to jog up or down by a distance equal to half the defect cluster diameter. Channels are predicted to form rapidly and are comparable to reported TEM measurements for many materials. Predicted channel widths are found to be most strongly dependent on mean defect size and correlated well with a power law dependence on defect diameter and density, and distance from the dislocation source. Due to the dependence of modeled channel width on defect diameter and density, maximum channel width is predicted to slowly increase as accumulated dose increases. The relatively weak predicted dependence of channel formation width with distance, in accordance with a diffusion analogy, implies that after only a few microns from the source, most channels observed via TEM analyses may not appear to vary with distance because of limitations in the field-of-view to a few microns. Furthermore, examinations of the effect of the so-called “source-broadening” mechanism of channel formation showed that its effect is simply to add a minimum thickness to the channel without affecting channel dependence on the given parameters.« less

21 CFR 888.3170 - Elbow joint radial (hemi-elbow) polymer prosthesis.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Elbow joint radial (hemi-elbow) polymer prosthesis. 888.3170 Section 888.3170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-elbow) polymer prosthesis. (a) Identification. An elbow joint radial (hemi-elbow) polymer...

21 CFR 888.3170 - Elbow joint radial (hemi-elbow) polymer prosthesis.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Elbow joint radial (hemi-elbow) polymer prosthesis. 888.3170 Section 888.3170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-elbow) polymer prosthesis. (a) Identification. An elbow joint radial (hemi-elbow) polymer...

21 CFR 888.3170 - Elbow joint radial (hemi-elbow) polymer prosthesis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Elbow joint radial (hemi-elbow) polymer prosthesis. 888.3170 Section 888.3170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-elbow) polymer prosthesis. (a) Identification. An elbow joint radial (hemi-elbow) polymer...

21 CFR 888.3170 - Elbow joint radial (hemi-elbow) polymer prosthesis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Elbow joint radial (hemi-elbow) polymer prosthesis. 888.3170 Section 888.3170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-elbow) polymer prosthesis. (a) Identification. An elbow joint radial (hemi-elbow) polymer...

21 CFR 888.3170 - Elbow joint radial (hemi-elbow) polymer prosthesis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Elbow joint radial (hemi-elbow) polymer prosthesis. 888.3170 Section 888.3170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-elbow) polymer prosthesis. (a) Identification. An elbow joint radial (hemi-elbow) polymer...

The role of strain hardening in the transition from dislocation-mediated to frictional deformation of marbles within the Karakoram Fault Zone, NW India

NASA Astrophysics Data System (ADS)

Wallis, David; Lloyd, Geoffrey E.; Hansen, Lars N.

2018-02-01

The onset of frictional failure and potentially seismogenic deformation in carbonate rocks undergoing exhumation within fault zones depends on hardening processes that reduce the efficiency of aseismic dislocation-mediated deformation as temperature decreases. However, few techniques are available for quantitative analysis of dislocation slip system activity and hardening in natural tectonites. Electron backscatter diffraction maps of crystal orientations offer one such approach via determination of Schmid factors, if the palaeostress conditions can be inferred and the critical resolved shear stresses of slip systems are constrained. We analyse calcite marbles deformed in simple shear within the Karakoram Fault Zone, NW India, to quantify changes in slip system activity as the rocks cooled during exhumation. Microstructural evidence demonstrates that between ∼300 °C and 200-250 °C the dominant deformation mechanisms transitioned from dislocation-mediated flow to twinning and frictional failure. However, Schmid factor analysis, considering critical resolved shear stresses for yield of undeformed single crystals, indicates that the fraction of grains with sufficient resolved shear stress for glide apparently increased with decreasing temperature. Misorientation analysis and previous experimental data indicate that strain-dependent work hardening is responsible for this apparent inconsistency and promoted the transition from dislocation-mediated flow to frictional, and potentially seismogenic, deformation.

Distributional and regularized radiation fields of non-uniformly moving straight dislocations, and elastodynamic Tamm problem

NASA Astrophysics Data System (ADS)

Lazar, Markus; Pellegrini, Yves-Patrick

2016-11-01

This work introduces original explicit solutions for the elastic fields radiated by non-uniformly moving, straight, screw or edge dislocations in an isotropic medium, in the form of time-integral representations in which acceleration-dependent contributions are explicitly separated out. These solutions are obtained by applying an isotropic regularization procedure to distributional expressions of the elastodynamic fields built on the Green tensor of the Navier equation. The obtained regularized field expressions are singularity-free, and depend on the dislocation density rather than on the plastic eigenstrain. They cover non-uniform motion at arbitrary speeds, including faster-than-wave ones. A numerical method of computation is discussed, that rests on discretizing motion along an arbitrary path in the plane transverse to the dislocation, into a succession of time intervals of constant velocity vector over which time-integrated contributions can be obtained in closed form. As a simple illustration, it is applied to the elastodynamic equivalent of the Tamm problem, where fields induced by a dislocation accelerated from rest beyond the longitudinal wave speed, and thereafter put to rest again, are computed. As expected, the proposed expressions produce Mach cones, the dynamic build-up and decay of which is illustrated by means of full-field calculations.

Arthroscopic repair of anterior-inferior glenohumeral instability using a portal at the 5:30-o'clock position: analysis of the effects of age, fixation method, and concomitant shoulder injury on surgical outcomes.

PubMed

Imhoff, Andreas B; Ansah, Patrick; Tischer, Thomas; Reiter, Christoph; Bartl, Christoph; Hench, Maximilian; Spang, Jeffrey T; Vogt, Stephan

2010-09-01

Traumatic anterior-inferior shoulder joint dislocations are common injuries among the young athletic population. The aim of this study was to assess which factors, including concomitant injury (rotator cuff tears, superior labral anterior posterior [SLAP] lesions), patient age, and fixation methods, led to redislocation after arthroscopic stabilization. There are several risk factors for the outcome after arthroscopic anterior-inferior glenohumeral stabilization. Cohort Study; Level of evidence, 3. Between 1996 and 2000, 221 patients were treated with arthroscopic stabilization for anterior-inferior shoulder dislocation. Of these 221 consecutive patients, 190 (140 male, 50 female) with an average age of 28.0 years (range, 14.4-59.2 years) were available for follow-up (average follow-up, 37.4 +/- 15.8 months). Fixation methods were FASTak (n = 138), Suretac (n = 28), or Panalok (n = 24) anchors. Concomitant SLAP lesions were seen in 38 of 190 cases (20%). Redislocation rates varied between anchor systems (FASTak, 6.5%; Suretac, 25%; Panalok, 16.8%). Superior labral anterior posterior lesions, when treated, did not influence clinical outcomes or redislocation rate. A concomitant rotator cuff tear did not influence redislocation rate. Postoperative outcomes (Rowe score, Constant score, American Shoulder and Elbow Surgeons [ASES] shoulder index, 12-item questionnaire) in patients with a partial tear were also not altered. On the other hand, the redislocation rate correlated with patient age and number of prior dislocations. Return to sports at preinjury level was possible in 80% of cases. Arthroscopic repair of anterior-inferior instability using the 5:30-o'clock portal is dependent on anchor type and can show good to excellent results. Because of several coinjuries in anterior-inferior instability, an arthroscopic approach may be required to identify and treat such lesions.

Three-dimensional scapular dyskinesis in hook-plated acromioclavicular dislocation including hook motion.

PubMed

Kim, Eugene; Lee, Seunghee; Jeong, Hwa-Jae; Park, Jai Hyung; Park, Se-Jin; Lee, Jaewook; Kim, Woosub; Park, Hee Jin; Lee, So Yeon; Murase, Tsuyoshi; Sugamoto, Kazuomi; Ikemoto, Sumika

2018-06-01

The purpose of this study is to analyze the 3-dimensional scapular dyskinesis and the kinematics of a hook plate relative to the acromion after hook-plated acromioclavicular dislocation in vivo. Reported complications of acromioclavicular reduction using a hook plate include subacromial erosion and impingement. However, there are few reports of the 3-dimensional kinematics of the hook and scapula after the aforementioned surgical procedure. We studied 15 cases of acromioclavicular dislocation treated with a hook plate and 15 contralateral normal shoulders using computed tomography in the neutral and full forward flexion positions. Three-dimensional motion of the scapula relative to the thorax during arm elevation was analyzed using a computer simulation program. We also measured the distance from the tip of the hook plate to the greater tuberosity, as well as the angular motion of the plate tip in the subacromial space. Decreased posterior tilting (22° ± 10° vs 31° ± 8°) in the sagittal plane and increased external rotation (19° ± 9° vs 7° ± 5°) in the axial plane were evident in the affected shoulders. The mean values of translation of the hook plate and angular motion against the acromion were 4.0 ± 1.6 mm and 15° ± 8°, respectively. The minimum value of the distance from the hook plate to the humeral head tuberosity was 6.9 mm during arm elevation. Acromioclavicular reduction using a hook plate may cause scapular dyskinesis. Translational and angular motion of the hook plate against the acromion could lead to subacromial erosion. However, the hook does not seem to impinge directly on the humeral head. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Dislocation dynamics simulations of plasticity at small scales

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhou, Caizhi

2010-01-01

As metallic structures and devices are being created on a dimension comparable to the length scales of the underlying dislocation microstructures, the mechanical properties of them change drastically. Since such small structures are increasingly common in modern technologies, there is an emergent need to understand the critical roles of elasticity, plasticity, and fracture in small structures. Dislocation dynamics (DD) simulations, in which the dislocations are the simulated entities, offer a way to extend length scales beyond those of atomistic simulations and the results from DD simulations can be directly compared with the micromechanical tests. The primary objective of this researchmore » is to use 3-D DD simulations to study the plastic deformation of nano- and micro-scale materials and understand the correlation between dislocation motion, interactions and the mechanical response. Specifically, to identify what critical events (i.e., dislocation multiplication, cross-slip, storage, nucleation, junction and dipole formation, pinning etc.) determine the deformation response and how these change from bulk behavior as the system decreases in size and correlate and improve our current knowledge of bulk plasticity with the knowledge gained from the direct observations of small-scale plasticity. Our simulation results on single crystal micropillars and polycrystalline thin films can march the experiment results well and capture the essential features in small-scale plasticity. Furthermore, several simple and accurate models have been developed following our simulation results and can reasonably predict the plastic behavior of small scale materials.« less

Barking up the wrong tree: injuries due to falls from trees in Solomon Islands.

PubMed

Negin, Joel; Vizintin, Pavle; Houasia, Patrick; Martiniuk, Alexandra L C

2014-12-11

To investigate tree-related injuries in Solomon Islands by the types of trees involved, who is affected and the types of injuries caused. Descriptive case series of all cases of injuries related to trees presenting to the National Referral Hospital in Honiara from 1994 to 2011. Data were collected by the attending clinician using a Trauma Epidemiology form, which provides information on age, sex, cause of injury and type of fracture. Number of injuries by tree type, sex and age. Of the 7651 injuries in the database, 1107 (14%) were caused by falls from trees. Falls from coconut trees led to the highest number of injuries, followed by falls from mango, guava, apple and nut trees. Overall, 85% of injuries occurred in individuals aged < 20 years. For injuries involving guava trees, 77% of patients were aged < 10 years, compared with 46% for the five most commonly involved tree types. Overall, 71% of injuries occurred among males. Of all injuries, 92% were fractures, 3% were dislocations and 5% were non-fracture, non-dislocation injuries. The arm (including wrist, elbow and hand) was the most common location of injury across all tree types. Distal radius fractures in the forearm were particularly common, as were ulna fractures. While mangos and guavas are undeniably delicious, the quest for their flesh can be hazardous. Children will always climb trees, but the search for food among children in lower-income settings may lead to higher rates of injury.

Active stiffness and strength in people with unilateral anterior shoulder instability: a bilateral comparison.

PubMed

Olds, Margie; McNair, Peter; Nordez, Antoine; Cornu, Christophe

2011-01-01

Active muscle stiffness might protect the unstable shoulder from recurrent dislocation. To compare strength and active stiffness in participants with unilateral anterior shoulder instability and to examine the relationship between active stiffness and functional ability. Cross-sectional study. University research laboratory. Participants included 16 males (age range, 16-40 years; height = 179.4 ± 6.1 cm; mass = 79.1 ± 6.8 kg) with 2 or more episodes of unilateral traumatic anterior shoulder instability. Active stiffness and maximal voluntary strength were measured bilaterally in participants. In addition, quality of life, function, and perceived instability were measured using the Western Ontario Stability Index, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form, and Single Alpha Numeric Evaluation, respectively. We found less horizontal adduction strength (t(15) = -4.092, P = .001) and less stiffness at 30% (t(14) = -3.796, P = .002) and 50% (t(12) = -2.341, P = .04) maximal voluntary strength in the unstable than stable shoulder. Active stiffness was not correlated with quality of life, function, or perceived instability (r range, 0.0-0.25; P > .05). The observed reduction in stiffness in the unstable shoulder warrants inclusion of exercises in the rehabilitation program to protect the joint from perturbations that might lead to dislocation. The lack of association between active stiffness and quality of life, function, or perceived instability might indicate that stiffness plays a less direct role in shoulder stability.

Elbow joint angle and elbow movement velocity estimation using NARX-multiple layer perceptron neural network model with surface EMG time domain parameters.

PubMed

Raj, Retheep; Sivanandan, K S

2017-01-01

Estimation of elbow dynamics has been the object of numerous investigations. In this work a solution is proposed for estimating elbow movement velocity and elbow joint angle from Surface Electromyography (SEMG) signals. Here the Surface Electromyography signals are acquired from the biceps brachii muscle of human hand. Two time-domain parameters, Integrated EMG (IEMG) and Zero Crossing (ZC), are extracted from the Surface Electromyography signal. The relationship between the time domain parameters, IEMG and ZC with elbow angular displacement and elbow angular velocity during extension and flexion of the elbow are studied. A multiple input-multiple output model is derived for identifying the kinematics of elbow. A Nonlinear Auto Regressive with eXogenous inputs (NARX) structure based multiple layer perceptron neural network (MLPNN) model is proposed for the estimation of elbow joint angle and elbow angular velocity. The proposed NARX MLPNN model is trained using Levenberg-marquardt based algorithm. The proposed model is estimating the elbow joint angle and elbow movement angular velocity with appreciable accuracy. The model is validated using regression coefficient value (R). The average regression coefficient value (R) obtained for elbow angular displacement prediction is 0.9641 and for the elbow anglular velocity prediction is 0.9347. The Nonlinear Auto Regressive with eXogenous inputs (NARX) structure based multiple layer perceptron neural networks (MLPNN) model can be used for the estimation of angular displacement and movement angular velocity of the elbow with good accuracy.

Tophaceous gout: quantitative evaluation by direct physical measurement.

PubMed

Schumacher, H Ralph; Becker, Michael A; Palo, William A; Streit, Janet; MacDonald, Patricia A; Joseph-Ridge, Nancy

2005-12-01

The absence of accepted standardized methods for monitoring tophaceous gout limits the ability to track tophus progression or regression. This multicenter study assessed intra- and interrater reproducibility of a simple and direct physical measurement. The quantitative evaluation was the area (mm2) of each measurable tophus and was determined independently by 2 raters on 2 occasions within 10 days. Intra- and interrater reproducibilities were determined by calculating mean differences and average percentage differences (APD) in measurements of areas for the same tophus at each of 2 visits and by each rater, respectively. Fifty-two tophi were measured in 13 subjects: 22 on the hand/wrist, 16 on the elbow, and 14 on the foot/ankle. The mean (+/- SD) difference in tophus areas between visits was -0.2 +/- 835 mm2 (95% CI -162 to 162 mm2) and the mean (+/- SD) APD was 29% +/- 33%. The mean (+/- SD) APD between raters was 32% +/- 27%. The largest variations in measurements were noted for elbow tophi and variations were least for well demarcated tophi on the hands. This simple and reproducible method can be easily utilized in clinical trials and in practice as a measure of efficacy of urate-lowering treatment in tophaceous gout. Among factors contributing to variability in these measurements were the anatomic site of tophi and rater experience with the method. Restriction of measurements to well circumscribed hand or foot tophi could improve reliability, but major changes, as expected with effective therapy, can clearly be documented with this simple technique.

Low- and High-Volume Water-Based Resistance Training Induces Similar Strength and Functional Capacity Improvements in Older Women: A Randomized Study.

PubMed

Reichert, Thaís; Delevatti, Rodrigo Sudatti; Prado, Alexandre Konig Garcia; Bagatini, Natália Carvalho; Simmer, Nicole Monticelli; Meinerz, Andressa Pellegrini; Barroso, Bruna Machado; Costa, Rochelle Rocha; Kanitz, Ana Carolina; Kruel, Luiz Fernando Martins

2018-03-27

Water-based resistance training (WRT) has been indicated to promote strength gains in elderly population. However, no study has compared different training strategies to identify the most efficient one. The aim of this study was to compare the effects of 3 WRT strategies on the strength and functional capacity of older women. In total, 36 women were randomly allocated to training groups: simple set of 30 seconds [1 × 30s; 66.41 (1.36) y; n = 12], multiple sets of 10 seconds [3 × 10s; 66.50 (1.43) y; n = 11], and simple set of 10 seconds [1 × 10s; 65.23 (1.09) y; n = 13]. Training lasted for 12 weeks. The maximal dynamic strength (in kilograms) and muscular endurance (number of repetitions) of knee extension, knee flexion, elbow flexion, and bench press, as well as functional capacity (number of repetitions), were evaluated. All types of training promoted similar gains in maximal dynamic strength of knee extension and flexion as well as elbow flexion. Only the 1 × 30s and 1 × 10s groups presented increments in bench press maximal strength. All 3 groups showed increases in muscular endurance in all exercises and functional capacity. WRT using long- or short-duration simple sets promotes the same gains in strength and functional capacity in older women as does WRT using multiple sets.

Significance of the Lateral Humeral Line for Evaluating Radiocapitellar Alignment in Children.

PubMed

Souder, Christopher D; Roocroft, Joanna H; Edmonds, Eric W

The radiocapitellar line (RCL) was originally described for evaluation of the alignment of the RC joint on lateral images of the elbow. Although, many authors have translated the utilization of RCL into coronal imaging, previous studies have not been performed to confirm validity. The purpose of this paper was to identify an accurate way of evaluating pediatric RC alignment in the coronal plane. Thirty-seven anteroposterior (AP) radiographs of 37 children were evaluated to determine the position of the RC joint in the coronal plane. All had acceptable magnetic resonance imaging (MRI) studies available for comparison. The lateral humeral line (LHL), consisting of a line along the lateral edge of the ossified condyle of the distal humerus parallel to the axis of the distal humeral shaft, was studied as it related to the lateral cortex of the radial neck. Three children with a confirmed diagnosis of a Bado III, lateral displaced radius, Monteggia fracture were also evaluated. The LHL passed along the edge of or lateral to the radial neck on all AP radiographs and all MRI studies. The RCL failed to intersect the capitellum on 2 AP radiographs. On MRI, the RCL also passed lateral to the capitellar ossification center in 3 patients. In addition, the RCL was seen passing through the capitellum at a mean of the lateral 30% (range, 0% to 64%) on AP radiographs and 26% (range, 0% to 48%) on MRI. For all 3 children with a Bado III Monteggia fracture, the LHL crossed the radial neck and the RCL did not intersect the capitellum. The RCL can fail to intersect the capitellar ossification center on AP radiographs and MRI in pediatric elbows without injury. The LHL consistently lies lateral to the radial neck in normal elbows and medial to the lateral aspect of the radial neck on all Bado III fracture-dislocations. It, therefore, can be used as an adjunct in evaluating the RC joint on AP imaging. The RCL most commonly intersects the lateral one third of the ossification center on both plain radiographs and MRIs. Level III-diagnostic.

Reverse shoulder prosthesis in the treatment of locked anterior shoulders: a comparison with classic reverse shoulder indications.

PubMed

Kurowicki, Jennifer; Triplet, Jacob J; Momoh, Enesi; Moor, Molly A; Levy, Jonathan C

2016-12-01

Locked anterior shoulder (LAS) with static instability and anterior glenoid bone loss is challenging in the elderly population. Reverse shoulder arthroplasty (RSA) has been employed in treating these patients. No study has compared RSA for LAS with classically indicated RSA. A retrospective case-control study of patients treated with RSA for LAS with glenoid bone loss and static instability was performed using matched controls treated with primary RSA for classic indications. Twenty-four cases and 48 controls were evaluated. Average follow-up was 25.5 months, and median age was 76 years. Motion, outcome assessments, and postoperative radiographs were compared. Preoperatively, LAS had significantly less rotation and lower baseline outcome scores. Glenoid bone grafting was more common (P = .05) in the control group (26%) than in the LAS group (6.3%). Larger glenospheres were used more often (P = .001) in the LAS group (75%) than in the control group (29%). Both groups demonstrated significant improvements in pain, function, and outcome scores. Postoperatively, the control group had significantly better elevation and functional outcome scores. With the exception of flexion and Simple Shoulder Test score, effectiveness of treatment was similar between groups. Postoperative acromion stress fractures were seen in 21% of LAS patients and 9% of controls (P = .023) with a predominance of type 3 fractures in LAS. Two LAS patients remained dislocated. Patients with LAS treated with RSA can anticipate improvements in pain and function by use of larger glenospheres, often without the need for glenoid bone grafting. Worse postoperative motion and function and a higher incidence of acromion stress fracture may be expected. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Solute segregation kinetics and dislocation depinning in a binary alloy

NASA Astrophysics Data System (ADS)

Dontsova, E.; Rottler, J.; Sinclair, C. W.

2015-06-01

Static strain aging, a phenomenon caused by diffusion of solute atoms to dislocations, is an important contributor to the strength of substitutional alloys. Accurate modeling of this complex process requires both atomic spatial resolution and diffusional time scales, which is very challenging to achieve with commonly used atomistic computational methods. In this paper, we use the recently developed "diffusive molecular dynamics" (DMD) method that is capable of describing the kinetics of the solute segregation process at the atomic level while operating on diffusive time scales in a computationally efficient way. We study static strain aging in the Al-Mg system and calculate the depinning shear stress between edge and screw dislocations and their solute atmospheres formed for various waiting times with different solute content and for a range of temperatures. A simple phenomenological model is also proposed that describes the observed behavior of the critical shear stress as a function of segregation level.

Primary osseous tumours of the elbow: 60 years of registry experience

PubMed Central

Halai, Mansur; Gupta, Sanjay; Wallace, David; Rymaszewski, Lech; Mahendra, Ashish

2015-01-01

Background We present the largest series of surgically treated primary bone tumours of the elbow in the English literature (75 cases). We sought to identify characteristics specific to these lesions and recommend an investigatory protocol. Methods The national registry and case notes were reviewed between 1954-2014. Tumours were classified according to Enneking's spectrum. Results There were no benign latent cases in this series as these were managed locally. All patients presented with persistent rest pain, with or without swelling. The distal humerus, in contrast to the proximal radius and ulna, was responsible for the majority and the more aggressive cases. Misdiagnosis was evident in 13% of cases; most of which were attributed to simple bone cysts. All patients that were referred required surgical intervention to either establish the diagnosis or for treatment. Benign tumours had a 19% recurrence rate, with giant cell tumour the most aggressive. Malignant tumours carried 39% local recurrence rate and a 5-year mortality of 61%. Conclusions The suspicion of a tumour should be raised in the patient with unremitting, unexplained, non-mechanical bony elbow pain. These echo the NICE recommendations and we recommend prompt specialist referral. With high rates of local recurrence, we recommend close postoperative monitoring. PMID:27582988

Elbow arthroscopy: indications, techniques, outcomes, and complications.

PubMed

Adams, Julie E; King, Graham J W; Steinmann, Scott P; Cohen, Mark S

2015-01-01

Elbow arthroscopy is a tool useful for the treatment of a variety of pathologies about the elbow. The major indications for elbow arthroscopy include débridement for septic elbow arthritis, synovectomy for inflammatory arthritis, débridement for osteoarthritis, loose body extraction, contracture release, treatment of osteochondral defects and selected fractures or instability, and tennis elbow release. To achieve favorable outcomes after elbow arthroscopy, the surgeon should be aware of contraindications, technical considerations, anatomic principles, and the need for proper patient positioning and portal selection. Elbow arthroscopy is an effective procedure for the treatment of inflammatory arthritis, osteoarthritis, and lateral epicondylitis.

[Intra-prosthetic dislocation of the Bousquet dual mobility socket].

PubMed

Lecuire, F; Benareau, I; Rubini, J; Basso, M

2004-05-01

The Bousquet system is a dual mobility head-polyethylene polyethylene-metal cup socket. The polyethylene insert retaining the femoral head moves in the noncemented metal cup, increasing both mobility and stability. Between 1989 and 1997, seven cases of intra-prosthetic dislocation (six patients) were observed. The femoral head escaped from the polyethylene insert due to wear. On the average, this complication occurred ten Years after implantation. Risk of dislocation was high in six of the seven hips. All patients had a large sized stem screwed into the femoral neck. There was a characteristic radiological aspect with loss of the concentric head metal cup configuration. The head was applied against the upper wall of the metal cup. Surgical replacement was undertaken early in six patients by simply changing the insert without modifying the other stable components. Outcome remained good at three to eight Years. One patient underwent late surgery. The insert and the cup were replaced with a classical implant. Functional outcome was good but recurrent dislocation occurred. At mid-term, intra-prosthetic dislocation of dual mobility sockets appears to be exceptional. Dislocation results from polyethylene wear leading to failure of the insert to retain the prosthetic head. Wear is favored by direct phenomena (direct contact between neck and insert which can occur early if there is a small difference in the head and neck diameters) or indirect phenomena (factors limiting polyethylene metal-cup mobility). Surgical treatment is necessary. If undertaken early, replacement with a modular head and insert can be sufficient if the prosthesis has not loosened but the metal cup may have to be replaced in the event of metal-metal contact between the head and the cup. Prosthesis loosening, wear of the metal cup, or an identified cause of dislocation imply replacing the failing implants. Implantation of the dual mobility system is particularly interesting for patients with a high risk of dislocation or a chronically unstable hip prosthesis. Careful technique is required to reduce or retard the risk of intra-prosthetic dislocation. Intra-prosthetic dislocation of a dual mobility socket is an exceptional complication at mid-term. Surgical treatment is required but may be limited to simple insert replacement. Systematic use of this type of implant in young subjects must be carefully examined, but for us, the risk of dislocation does not outweigh the advantages of this original concept of dual mobility. This type of socket remains an useful preventive technique for high-risk hips or for curative treatment of recurrent dislocation.

Lubrication of dislocation glide in MgO by hydrous defects

NASA Astrophysics Data System (ADS)

Skelton, Richard; Walker, Andrew M.

2018-02-01

Water-related defects, principally in the form of protonated cation vacancies, are potentially able to weaken minerals under high-stress or low-temperature conditions by reducing the Peierls stress required to initiate dislocation glide. In this study, we use the Peierls-Nabarro (PN) model to determine the effect of protonated Mg vacancies on the 1/2<110>{110} and 1/2<110>{100} slip systems in MgO. This PN model is parameterized using generalized stacking fault energies calculated using plane-wave density functional theory, with and without protonated Mg vacancies present at the glide plane. It found that these defects increase dislocation core widths and reduce the Peierls stress over the entire pressure range 0-125 GPa. Furthermore, 1/2<110>{110} slip is found to be more sensitive to the presence of protonated vacancies which increases in the pressure at which {100} becomes the easy glide plane for 1/2<110> screw dislocations. These results demonstrate, for a simple mineral system, that water-related defects can alter the deformation behavior of minerals in the glide-creep regime by reducing the stress required to move dislocations by glide. (Mg, Fe)O is the most anisotropic mineral in the Earth's lower mantle, so the differential sensitivity of the major slip systems in MgO to hydrous defects has potential implications for the interpretation of the seismic anisotropy in this region.

Experimental measurement of flexion-extension movement in normal and corpse prosthetic elbow joint.

PubMed

TarniŢă, Daniela; TarniŢă, DănuŢ Nicolae

2016-01-01

This paper presents a comparative experimental study of flexion-extension movement in healthy elbow and in the prosthetic elbow joint fixed on an original experimental bench. Measurements were carried out in order to validate the functional morphology and a new elbow prosthesis type ball head. The three-dimensional (3D) model and the physical prototype of our experimental bench used to test elbow endoprosthesis at flexion-extension and pronation-supination movements is presented. The measurements were carried out on a group of nine healthy subjects and on the prosthetic corpse elbow, the experimental data being obtained for flexion-extension movement cycles. Experimental data for the two different flexion-extension tests for the nine subjects and for the corpse prosthetic elbow were acquired using SimiMotion video system. Experimental data were processed statistically. The corresponding graphs were obtained for all subjects in the experimental group, and for corpse prosthetic elbow for both flexion-extension tests. The statistical analysis has proved that the flexion angles of healthy elbows were significantly close to the values measured at the prosthetic elbow fixed on the experimental bench. The studied elbow prosthesis manages to re-establish the mobility for the elbow joint as close to the normal one.

Risk factors for shoulder and elbow pain in youth baseball players.

PubMed

Matsuura, Tetsuya; Iwame, Toshiyuki; Suzue, Naoto; Arisawa, Kokichi; Sairyo, Koichi

2017-05-01

This study sought to quantify the 1-year cumulative incidence of shoulder and elbow pain among youth baseball players and identify risk factors associated with the occurrence of shoulder and elbow pain. In total, 900 youth baseball players (aged 7-11 years) were enrolled in a 1-year prospective follow-up study. One year later, the players were asked whether they had experienced episodes of shoulder or elbow pain and the following risk factors for such pain were investigated: age, position, length of baseball experience, training hours per week, and history of shoulder or elbow pain. Data for the groups with and without shoulder or elbow pain were analyzed using multivariate logistic regression models. Episodes of shoulder pain were reported by 18.3% of players and episodes of elbow pain were reported by 35.2% of players. Multivariate analysis showed that shoulder pain was associated with pitcher position, catcher position, longer training hours per week, and history of shoulder and elbow pain, and that elbow pain was associated with age, pitcher position, catcher position, longer training hours per week, and history of elbow pain. Length of baseball experience was not associated with shoulder or elbow pain. History of elbow pain, pitcher position, catcher position, and longer training hours per week were associated with both types of pain. History of shoulder pain was associated with shoulder pain but not elbow pain. Age was associated with elbow pain but not shoulder pain.

Materials science. Modeling strain hardening the hard way.

PubMed

Gumbsch, Peter

2003-09-26

The plastic deformation of metals results in strain hardening, that is, an increase in the stress with increasing strain. Materials engineers can provide a simple approximate description of such deformation and hardening behavior. In his perspective, Gumbsch discusses work by Madec et al. who have undertaken the formidable task of computing the physical basis for the development of strain hardening by individually following the fate of all the dislocations involved. Their simulations show that the collinear dislocation interaction makes a substantial contribution to strain hardening. It is likely that such simulations will play an important role in guiding the development of future engineering descriptions of deformation and hardening.

Comparative Readability of Shoulder and Elbow Patient Education Materials within Orthopaedic Websites.

PubMed

Beutel, Bryan G; Danna, Natalie R; Melamed, Eitan; Capo, John T

2015-12-01

There is growing concern that the readability of online orthopaedic patient education materials are too difficult for the general public to fully understand. It is recommended that this information be at the sixth grade reading level or lower. This study compared the readability of shoulder and elbow education articles from the American Academy of Orthopaedic Surgeons (AAOS) and American Society for Surgery of the Hand (ASSH) websites. Seventy-six patient education articles from the AAOS and ASSH concerning shoulder and elbow disorders were evaluated. Each article was assessed for the number of years since its last update, word count, percentage of passive sentences, Flesch Reading Ease score, Flesch-Kincaid grade level, Simple Measure of Gobbledygook (SMOG) grade, and New Dale-Chall grade level. Only one article was at or below the sixth grade reading level. The AAOS and ASSH articles had the following respective scores: a mean Flesch Reading Ease score of 54.3 and 51.8, Flesch-Kincaid grade level of 9.4 and 10.3, SMOG grade of 8.5 and 9.4, and New Dale-Chall grade of 10.4 and 11.0. Articles from the AAOS were longer (p < 0.001), had a lower percentage of passive sentences (p < 0.001), and were more recently updated (p = 0.02) than their ASSH counterparts. Higher percentages of passive sentences were found to correlate with more difficult readability. Patient education materials regarding the shoulder and elbow on the AAOS and ASSH websites have readability scores above the recommended reading level. These may be too challenging for the majority of patients to read and consequently serve as a barrier to proper patient education. Reducing the percentage of passive sentences may serve as a novel target for improving readability.

Posterolateral Rotatory Apprehension Test in Tennis Elbow.

PubMed

Chanlalit, Cholawish; Phorkhar, Termphong

2015-11-01

Tennis elbow is a syndrome that commonly diagnosed in patient who comes with lateral elbow pain. Instability pain in tennis elbow patient was observed and reported in many previous literatures. Posterolateral rotatory apprehension test was proposed for diagnosis of posterolateral rotatory instability of elbow. However, no review literatures that studied about posterolateral rotatory apprehensions test in tennis elbow. To find out the relationship between posterolateral rotatory apprehension test and tennis elbow. There were 44 patients that were recruited in this study. We examined the posterolateral rotatory apprehension test in tennis elbow patients. The examination was done in our outpatient clinic from March 2012 to April 2012. The data was collected to find out the ratio of negative test in tennis elbow patient. The results from the posterolateral rotatory apprehension test were negative in 43 patients. The ratio of the negative test result was 98%. A result from posterolateral rotatory apprehension test should be negative in general tennis elbow patients. If this test is used in a tennis elbow patients who are suspected with hidden instability and the result is positive, further evaluation is strongly suggested.

Ultrasound-Guided Elbow Procedures.

PubMed

Sussman, Walter I; Williams, Christopher J; Mautner, Ken

2016-08-01

High-resolution ultrasonography can help clinicians visualize key anatomic structures of the elbow and guide periarticular and intra-articular injections. Historically, most procedures done around the elbow have been done using landmark guidance, and few studies have reported the accuracy of ultrasonography-guided injections in the elbow region. This article reviews common musculoskeletal disorders about the elbow that can be evaluated with ultrasonography, reviews the literature on ultrasonography-guided injections of the elbow region, and describes the senior author's preferred approach for the most commonly performed elbow region injections. Copyright © 2016 Elsevier Inc. All rights reserved.

Shoulder internal rotation elbow flexion test for diagnosing cubital tunnel syndrome.

PubMed

Ochi, Kensuke; Horiuchi, Yukio; Tanabe, Aya; Waseda, Makoto; Kaneko, Yasuhito; Koyanagi, Takahiro

2012-06-01

Shoulder internal rotation enhances symptom provocation attributed to cubital tunnel syndrome. We present a modified elbow flexion test--the shoulder internal rotation elbow flexion test--for diagnosing cubital tunnel syndrome. Fifty-five ulnar nerves in cubital tunnel syndrome patients and 123 ulnar nerves in controls were examined with 5 seconds each of elbow flexion, shoulder internal rotation, and shoulder internal rotation elbow flexion tests before and after treatment (surgery in 18; conservative in others). For the shoulder internal rotation elbow flexion test position, 90° abduction, maximum internal rotation, and 10° flexion of the shoulder were combined with the elbow flexion test position. The test was considered positive if any symptom for cubital tunnel syndrome developed <5 seconds. Influence of the shoulder internal rotation elbow flexion test was evaluated by nerve conduction studies in 10 cubital tunnel syndrome nerves and 7 control nerves. The sensitivities/specificities of the 5-second elbow flexion, shoulder internal rotation, and shoulder internal rotation elbow flexion tests were 25%/100%, 58%/100%, and 87%/98%, respectively. Sensitivity differences between the shoulder internal rotation elbow flexion test and the other two tests were significant. Shoulder internal rotation elbow flexion test results and cubital tunnel syndrome symptoms were significantly correlated. Influence of the shoulder internal rotation elbow flexion test on the ulnar nerve was seen in 8 of 10 cubital tunnel syndrome nerves but not in controls. The 5-second shoulder internal rotation elbow flexion test is specific, easy and quick provocative test for diagnosing cubital tunnel syndrome. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Elbow arthroscopy: indications, techniques, outcomes, and complications.

PubMed

Adams, Julie E; King, Graham J W; Steinmann, Scott P; Cohen, Mark S

2014-12-01

Elbow arthroscopy is a tool useful for the treatment of a variety of pathologies about the elbow. The major indications for elbow arthroscopy include débridement for septic elbow arthritis, synovectomy for inflammatory arthritis, débridement for osteoarthritis, loose body extraction, contracture release, treatment of osteochondral defects and selected fractures or instability, and tennis elbow release. Contraindications, technical considerations, and favorable outcomes following treatment with elbow arthroscopy require careful patient evaluation, a thorough understanding of anatomic principles, and proper patient positioning and portal selection to guide preoperative planning and overall patient care. Elbow arthroscopy is an effective procedure for the treatment of inflammatory arthritis, osteoarthritis, and lateral epicondylitis. Copyright 2014 by the American Academy of Orthopaedic Surgeons.

Elbow replacement

MedlinePlus

... arthroplasty Patient Instructions Elbow replacement - discharge Surgical wound care - open Images Elbow prosthesis References Cohen MS, Chen NC. Total elbow arthroplasty. In: Wolfe SW, Hotchkiss RN, Pederson ...

Failure after reverse total shoulder arthroplasty: what is the success of component revision?

PubMed

Black, Eric M; Roberts, Susanne M; Siegel, Elana; Yannopoulos, Paul; Higgins, Laurence D; Warner, Jon J P

2015-12-01

Complication rates remain high after reverse total shoulder arthroplasty (RTSA). Salvage options after implant failure have not been well defined. This study examines the role of reimplantation and revision RTSA after failed RTSA, reporting outcomes and complications of this salvage technique. Sixteen patients underwent component revision and reimplantation after a prior failed RTSA from 2004 to 2011. Indications included baseplate failure (7 patients, 43.8%), instability (6 patients, 37.5%), infection (2 patients, 12.5%), and humeral loosening (1 patient, 6.3%). The average age of the patient during revision surgery was 68.6 years. Outcomes information at follow-up was recorded, including visual analog scale score for pain, subjective shoulder value, American Shoulder and Elbow Surgeons score, and Simple Shoulder Test score, and these were compared with pre-revision values. Repeated surgeries and complications were noted. Average time to follow-up from revision was 58.9 months (minimum, 2 years; range, 24-103 months). The average postoperative visual analog scale score for pain was 1.7/10 (7.5/10 preoperatively; P < .0001), and the subjective shoulder value was 62% (17% preoperatively; P < .0001). The average postoperative American Shoulder and Elbow Surgeons score was 66.7, and the Simple Shoulder Test score was 52.6. Fourteen patients (88%) noted that they felt "better" postoperatively than before their original RTSA and would go through the procedure again if given the option. Nine patients suffered major complications (56%), and 6 of these ultimately underwent further procedures (38% of cohort). Salvage options after failure of RTSA remain limited. Component revision and reimplantation can effectively relieve pain and improve function compared with baseline values, and patient satisfaction levels are moderately high. However, complication rates and reoperation rates are significant. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Human Toddlers’ Attempts to Match Two Simple Behaviors Provide No Evidence for an Inherited, Dedicated Imitation Mechanism

PubMed Central

Jones, Susan S.

2012-01-01

Influential theories of imitation have proposed that humans inherit a neural mechanism – an “active intermodal matching “ (AIM) mechanism or a mirror neuron system - that functions from birth to automatically match sensory input from others’ actions to motor programs for performing those same actions, and thus produces imitation. To test these proposals, 160 1- to 2½-year-old toddlers were asked to imitate two simple movements– bending the arm to make an elbow, and moving the bent elbow laterally. Both behaviors were almost certain to be in each child’s repertoire, and the lateral movement was goal-directed (used to hit a plastic cup). Thus, one or both behaviors should have been imitable by toddlers with a functioning AIM or mirror neuron system. Each child saw the two behaviors repeated 18 times, and was encouraged to imitate. Children were also asked to locate their own elbows. Almost no children below age 2 imitated either behavior. Instead, younger children gave clear evidence of a developmental progression, from reproducing only the outcome of the models’ movements (hitting the object), through trying (but failing) to reproduce the model’s arm posture and/or the arm-cup relations they had seen, to accurate imitation of arm bending by age 2 and of both movements by age 2½. Across age levels, almost all children who knew the word ‘elbow’ imitated both behaviors: very few who did not know the word imitated either behavior. The evidence is most consistent with a view of early imitation as the product of a complex system of language, cognitive, social, and motor competencies that develop in infancy. The findings do not rule out a role for an inherited neural mechanism, but they suggest that such a system would not by itself be sufficient to explain imitation at any age. PMID:23251500

Prevalence of posterior elbow problems in Japanese high school baseball players.

PubMed

Kida, Yoshikazu; Morihara, Toru; Furukawa, Ryuhei; Sukenari, Tsuyoshi; Kotoura, Yoshihiro; Yoshioka, Naoki; Hojo, Tatsuya; Oda, Ryo; Arai, Yuji; Sawada, Koshiro; Fujiwara, Hiroyoshi; Kubo, Toshikazu

2016-09-01

Various posterior elbow problems cause posterior elbow pain among baseball players. We aimed to determine the prevalence and diagnoses associated with posterior elbow problems and post-treatment recovery time for returning to sports in Japanese high school baseball players when treated in the off-season. A total of 576 Japanese high school baseball players who participated in baseball skill training camp during the off-season were enrolled in the study. The elbow of each player's throwing arm was assessed by use of a questionnaire and physical examination. Players with abnormal results were advised to visit the hospital. Players who visited the hospital were initially treated conservatively and underwent surgery if necessary. Retrospectively, players with positive physical examination results associated with posterior elbow pain, defined as olecranon tenderness and/or a positive elbow extension impingement test, were selected. Information about their position, elbow pain, physical examination results, diagnosis, treatment, and recovery time before returning to playing sports was assessed. Olecranon tenderness and/or positive elbow extension impingement test results were found in 76 players (13.2%). Of these, 33 agreed to visit the hospital for further diagnostic imaging and 25 players (75.8%) were diagnosed with posteromedial elbow impingement. By the next spring, 87.9% of players returned to sport, and 100% of players returned to sport before the next summer. The average recovery period was 77 ± 47 days. Physical examinations related to posterior elbow injuries were positive in 13.2% of high school baseball players. The most common diagnosis for posterior elbow pain was posteromedial elbow impingement. All players returned to competitive sports activity levels within 77 ± 47 days. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Factors affecting the stability of reverse shoulder arthroplasty: a biomechanical study.

PubMed

Clouthier, Allison L; Hetzler, Markus A; Fedorak, Graham; Bryant, J Tim; Deluzio, Kevin J; Bicknell, Ryan T

2013-04-01

Despite the success of reverse shoulder arthroplasty (RSA) in treating patients with painful pseudoparalytic shoulders, instability is a common complication and currently the factors affecting stability are not well understood. The objective of this study was to investigate a number of factors as well as the interactions between factors to determine how they affect the stability of the prosthesis. These factors included: active arm posture (abduction and abduction plane angles), loading direction, glenosphere diameter and eccentricity, and humeral socket constraint. Force required to dislocate the joint, determined using a biomechanical shoulder simulator, was used as a measure of stability. A factorial design experiment was implemented to examine the factors and interactions. Actively increasing the abduction angle by 15° leads to a 30% increase in stability and use of an inferior-offset rather than a centered glenosphere improved stability by 17%. Use of a more constrained humeral socket also increased stability; but the effect was dependent on loading direction, with a 88% improvement for superior loading, 66% for posterior, 36% for anterior, and no change for inferior loading. Abduction plane angle and glenosphere diameter had no effect on stability. Increased glenohumeral abduction and the use of an inferior-offset glenosphere were found to increase the stability of RSA. Additionally, use of a more constrained humeral socket increased stability for anterior, posterior, and superior loading. These identified factor effects have the potential to decrease the risk of dislocation following RSA. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Study on the anatomic relationship between the clavicle and the coracoid process using computed tomography scans of the shoulder.

PubMed

Sella, Guilherme do Val; Miyazaki, Alberto N; Nico, Marcelo A C; Filho, Guinel H; Silva, Luciana A; Checchia, Sergio L

2017-10-01

The current trend in the treatment of acromioclavicular dislocations is to reconstruct the coracoclavicular ligaments by using transosseous tunnels in the coracoid process or in the clavicle, yet there is no definition as to the location of these. To study the anatomic relationship between the coracoid process and the clavicle, we made measurements to find a convergence point (cP) between them that has intraoperative applicability for creating transosseous tunnels. We analyzed 74 computed tomography scans (40 female and 34 male patients). Measurements were taken in the axial and sagittal planes and obtained from a cP, as determined by the intersection of the cortical surface of the clavicle and the coracoid process, with various relationships having been established. On average, the cP was determined to be about 2.9 cm and 2.5 cm distant from the coracoid process apex for male and female patients, respectively, whereas the width at this position was determined to be 2.1 cm and 1.9 cm. In the clavicle, this point is on average 2.9 cm and 2.5 cm distant from the acromioclavicular joint in male and female patients, respectively, and its anteroposterior width at this point is on average 1.9 cm and 1.6 cm. The cP of the clavicle and the coracoid process was determined with the aim of preparing bone tunnels in operations for treating acromioclavicular dislocations. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

21 CFR 888.3160 - Elbow joint metal/polymer semi-constrained cemented prosthesis.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Elbow joint metal/polymer semi-constrained... Elbow joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An elbow joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an elbow...

21 CFR 888.3160 - Elbow joint metal/polymer semi-constrained cemented prosthesis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Elbow joint metal/polymer semi-constrained... Elbow joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An elbow joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an elbow...

21 CFR 888.3160 - Elbow joint metal/polymer semi-constrained cemented prosthesis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Elbow joint metal/polymer semi-constrained... Elbow joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An elbow joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an elbow...

21 CFR 888.3160 - Elbow joint metal/polymer semi-constrained cemented prosthesis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Elbow joint metal/polymer semi-constrained... Elbow joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An elbow joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an elbow...

Manipulation of domain-wall solitons in bi- and trilayer graphene

NASA Astrophysics Data System (ADS)

Jiang, Lili; Wang, Sheng; Shi, Zhiwen; Jin, Chenhao; Utama, M. Iqbal Bakti; Zhao, Sihan; Shen, Yuen-Ron; Gao, Hong-Jun; Zhang, Guangyu; Wang, Feng

2018-01-01

Topological dislocations and stacking faults greatly affect the performance of functional crystalline materials1-3. Layer-stacking domain walls (DWs) in graphene alter its electronic properties and give rise to fascinating new physics such as quantum valley Hall edge states4-10. Extensive efforts have been dedicated to the engineering of dislocations to obtain materials with advanced properties. However, the manipulation of individual dislocations to precisely control the local structure and local properties of bulk material remains an outstanding challenge. Here we report the manipulation of individual layer-stacking DWs in bi- and trilayer graphene by means of a local mechanical force exerted by an atomic force microscope tip. We demonstrate experimentally the capability to move, erase and split individual DWs as well as annihilate or create closed-loop DWs. We further show that the DW motion is highly anisotropic, offering a simple approach to create solitons with designed atomic structures. Most artificially created DW structures are found to be stable at room temperature.

Hardening mechanisms in olivine single crystal deformed at 1090 °C: an electron tomography study

NASA Astrophysics Data System (ADS)

Mussi, Alexandre; Cordier, Patrick; Demouchy, Sylvie; Hue, Benoit

2017-11-01

The dislocation microstructures in a single crystal of olivine deformed experimentally in uniaxial compression at 1090 °C and under a confining pressure of 300 MPa, have been investigated by transmission electron tomography in order to better understand deformation mechanisms at the microscale relevant for lithospheric mantle deformations. Investigation by electron tomography reveals microstructures, which are more complex than previously described, composed of ? and ? dislocations commonly exhibiting 3D configurations. Numerous mechanisms such as climb, cross-slip, double cross-slip as well as interactions like junction formations and collinear annihilations are the source of this complexity. The diversity observed advocates for microscale deformation of olivine significantly less simple than classic dislocation creep reported in metals or ice close to melting temperature. Deciphering mechanism of hardening in olivine at temperatures where ionic diffusion is slow and is then expected to play very little role is crucial to better understand and thus model deformation at larger scale and at temperatures (900-1100 °C) highly relevant for the lithospheric mantle.

A quantitative evaluation of the high elbow technique in front crawl.

PubMed

Suito, Hiroshi; Nunome, Hiroyuki; Ikegami, Yasuo

2017-07-01

Many coaches often instruct swimmers to keep the elbow in a high position (high elbow position) during early phase of the underwater stroke motion (pull phase) in front crawl, however, the high elbow position has never been quantitatively evaluated. The aims of this study were (1) to quantitatively evaluate the "high elbow" position, (2) to clarify the relationship between the high elbow position and required upper limb configuration and (3) to examine the efficacy of high elbow position on the resultant swimming velocity. Sixteen highly skilled and 6 novice male swimmers performed 25 m front crawl with maximal effort and their 3-dimensional arm stroke motion was captured at 60 Hz. An attempt was made to develop a new index to evaluate the high elbow position (I he : high elbow index) using 3-dimensional coordinates of the shoulder, elbow and wrist joints. I he of skilled swimmers moderately correlated with the average shoulder internal rotation angle (r = -0.652, P < 0.01) and swimming velocity (r = -0.683, P < 0.01) during the pull phase. These results indicate that I he is a useful index for evaluating high elbow arm stroke technique during the pull phase in front crawl.

Reverse shoulder arthroplasty in patients with os acromiale.

PubMed

Aibinder, William R; Schoch, Bradley S; Cofield, Robert H; Sperling, John W; Sánchez-Sotelo, Joaquin

2017-09-01

Os acromiale has been reported in up to 15% of the general population. Reverse total shoulder arthroplasty (RTSA) increases deltoid tension, which could potentially lead to excessive stress on a pre-existent os acromiale. The purpose of this study was to determine the outcome and complications of primary RTSA in patients with radiographic evidence of an os acromiale. Between 2005 and 2013, 25 shoulders underwent primary RTSA with an associated os acromiale, which was classified preacromion (3), mesoacromion (20), and meta-acromion (2). All patients were observed for a minimum of 2 years or until reoperation. Mean follow-up time was 30.8 (range, 1-81.4) months. Outcomes included pain scores, range of motion, patient satisfaction, American Shoulder and Elbow Surgeons scores, and radiographic outcomes. RTSA led to an improvement in pain scores in 24 of 25 shoulders. Mean elevation, external rotation, and internal rotation were improved at final follow-up (124°, 46°, and L4, respectively). Three patients required reoperation, including revision surgery for dislocation (2) and excision of a painful os acromiale (1). Postoperative tilting of the os acromiale was noted in 7 shoulders (28%). There was no statistically significant difference in any outcome measures between shoulders with and shoulders without postoperative tilt of the os acromiale. The outcome of RTSA does not seem to be negatively affected by the presence of an os acromiale. Pain around an os acromiale after RTSA is rare. Inferior tilting is observed in approximately one-third of the shoulders after RTSA and does not seem to change the overall outcome. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Scapular allograft reconstruction after total scapulectomy: surgical technique and functional results.

PubMed

Capanna, Rodolfo; Totti, Francesca; Van der Geest, Ingrid C M; Müller, Daniel A

2015-08-01

Scapular allograft reconstruction after total scapulectomy preserving the rotator cuff muscles is an oncologically safe procedure and results in good functional outcome with a low complication rate. The data of 6 patients who underwent scapular allograft reconstruction after a total scapulectomy for tumor resection were retrospectively reviewed. At least 1 of the rotator cuff muscles was preserved and the size-matched scapular allograft fixed to the residual host acromion with a plate and screws. The periscapular muscles and the residual joint capsule were sutured to the corresponding insertions of the allograft. The mean follow-up was 5.5 years (range, 24-175 months). In all patients, a wide surgical margin was achieved. The average functional scores were 20 points for the International Society of Limb Salvage score and 60 points for the American Shoulder and Elbow Surgeons score. Mean active shoulder flexion of 60° (range, 30°-90°) and mean active abduction of 62° (range, 30°-90°) were achieved. During the follow-up, 1 patient (16.6%) had a local recurrence and lung metastasis, whereas the remaining 5 patients (83.3%) were disease free. Two breakages of the osteosynthesis and 2 allograft fractures were observed, necessitating a revision surgery in 2 cases (33.3%). In this series, no infection, allograft resorption, or shoulder instability occurred. Allograft substitution of a completely removed scapula is an oncologically safe procedure, with good functional results, avoiding common complications in prosthetic replacements such as infection and dislocation of the shoulder joint. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Arthroscopic Bankart repair and subscapularis augmentation: an alternative technique treating anterior shoulder instability with bone loss.

PubMed

Maiotti, Marco; Russo, Raffaele; Zanini, Antonio; Schröter, Steffen; Massoni, Carlo; Bianchedi, Diana

2016-06-01

This study presents the preliminary results of a new arthroscopic technique consisting of the association of 2 procedures, capsulolabral repair and subscapularis augmentation tenodesis, in the treatment of traumatic anterior shoulder instability with both glenoid bone loss and a Hill-Sachs lesion. Eighty-nine patients engaged in sports were enrolled in this retrospective case-series study with 2 to 5 years' follow-up. All patients underwent a computed tomography scan to assess the percentage of glenoid bone loss by the Pico method. A prior stabilization procedure had failed in 20 patients, who were then segregated into a different group. Visual analog scale (VAS), Rowe, and American Shoulder and Elbow Surgeons (ASES) scores were used to assess the results. Only 3 of 89 patients had a post-traumatic redislocation. The mean length of follow-up was 31.5 months (range, 25-60 months). The VAS, Rowe, and ASES scores showed significant improvements: The VAS score decreased from a mean of 3.1 to 0.5 (P = .0157), the Rowe score increased from 58.9 to 94.1 (P = .0215), and the ASES score increased from 68.5 to 95.5 (P = .0197). The mean deficit of external rotation was 6° with the arm at the side of the trunk, and the mean deficit was 3° with the arm in 90° of abduction. The described procedure is a reproducible and effective technique used to restore joint stability in patients engaged in sports who have incurred anterior recurrent shoulder dislocation associated with glenoid bone loss (<25%) and a Hill-Sachs lesion. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Survey of upper extremity injuries among martial arts participants.

PubMed

Diesselhorst, Matthew M; Rayan, Ghazi M; Pasque, Charles B; Peyton Holder, R

2013-01-01

To survey participants at various experience levels of different martial arts (MA) about upper extremity injuries sustained during training and fighting. A 21-s question survey was designed and utilised. The survey was divided into four groups (Demographics, Injury Description, Injury Mechanism, and Miscellaneous information) to gain knowledge about upper extremity injuries sustained during martial arts participation. Chi-square testing was utilised to assess for significant associations. Males comprised 81% of respondents. Involvement in multiple forms of MA was the most prevalent (38%). The hand/wrist was the most common area injured (53%), followed by the shoulder/upper arm (27%) and the forearm/elbow (19%). Joint sprains/muscle strains were the most frequent injuries reported overall (47%), followed by abrasions/bruises (26%). Dislocations of the upper extremity were reported by 47% of participants while fractures occurred in 39%. Surgeries were required for 30% of participants. Females were less likely to require surgery and more likely to have shoulder and elbow injuries. Males were more likely to have hand injuries. Participants of Karate and Tae Kwon Do were more likely to have injuries to their hands, while participants of multiple forms were more likely to sustain injuries to their shoulders/upper arms and more likely to develop chronic upper extremity symptoms. With advanced level of training the likelihood of developing chronic upper extremity symptoms increases, and multiple surgeries were required. Hand protection was associated with a lower risk of hand injuries. Martial arts can be associated with substantial upper extremity injuries that may require surgery and extended time away from participation. Injuries may result in chronic upper extremity symptoms. Hand protection is important for reducing injuries to the hand and wrist.

An Integrated Approach to Social Work Practice in Nigeria

ERIC Educational Resources Information Center

Kazeem, Kolawole

2011-01-01

The number of people in need of care, support and assistance from afflictions (natural and artificial) keeps expanding by the day. From a simple traditional based dislocation to a sophisticated "man induced" social problems of wars, refugees, drug addiction, homosexuality, HIV/AIDS pandemics etc, the society today (either developed or…

78 FR 59808 - Standard Instrument Approach Procedures, and Takeoff Minimums and Obstacle Departure Procedures...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-30

... ODPs, in addition to their complex nature and the need for a special format make publication in the...-Lapeer, RNAV (GPS) RWY 36, Orig Elbow Lake, MN, Elbow Lake Muni--Pride of the Prairie, RNAV (GPS) RWY 14, Orig Elbow Lake, MN, Elbow Lake Muni--Pride of the Prairie, RNAV (GPS) RWY 32, Orig Elbow Lake, MN...

Does Excision of Heterotopic Ossification of the Elbow Result in Satisfactory Patient-Rated Outcomes?

PubMed

Sandeep, K N; Suresh, G; Gopisankar, B; Abhishek, N; Sujiv, A

2017-03-01

Treatment of heterotopic ossification (HO) of the elbow is challenging and fraught with complications. Patients who sustain direct trauma to the elbow joint, the central nervous system, and thermal burns are at increased risk for development of HO. There is a paucity of studies and reports on patient's self-evaluation after the excision of the heterotopic ossification. This retrospective study assessed outcomes after excision of heterotopic ossification around the elbow in a cohort of ten patients operated from 2012 to 2015. The outcome assessment was done by the Mayo Elbow Performance index (MEPI) and the American Shoulder and Elbow Surgeons-Elbow score (ASES-E scores). The mean follow-up was 18.11 months after the operation. The Mayo Elbow Performance Score was excellent in two elbows, good in six and fair in two. The mean gain in flexion-extension arc after excision of HO was 80 degrees. All of the patients had residual flexion deformity postoperatively. Eight of the nine patients were able to do activities requiring flexion at final follow-up. Excision of HO around the elbow is associated with satisfactory patient-rated outcomes in spite of failure to regain full range of motion.

Biomechanical comparison of graft fixation at 30° and 90° of elbow flexion for ulnar collateral ligament reconstruction by the docking technique.

PubMed

Cohen, Steven B; Woods, Daniel P; Siegler, Sorin; Dodson, Christopher C; Namani, Ramya; Ciccotti, Michael G

2015-02-01

Ulnar collateral ligament (UCL) injuries have been successfully treated by the docking reconstruction. Although fixation of the graft has been suggested at 30° of elbow flexion, no quantitative biomechanical data exist to provide guidelines for the optimal elbow flexion angle for graft fixation. Testing was conducted on 10 matched pairs of cadaver elbows with use of a loading system and optoelectric tracking device. After biomechanical data on the native UCL were obtained, reconstruction by the docking technique was performed with use of palmaris longus autograft with one elbow fixated at 30° and the contralateral elbow at 90° of elbow flexion. Biomechanical testing was undertaken on these specimens. The load to failure of the native UCL (mean, 20.1 N-m) was significantly higher (P = .004) than that of the reconstructed UCL (mean, 4.6 N-m). There was no statistically significant difference in load to failure of the UCL reconstructions fixated at 30° of elbow flexion (average, 4.86 N-m) compared with those at 90° (average, 4.35 N-m). Elbows reconstructed at 30° and 90° of elbow flexion produced similar kinematic coupling and valgus laxity characteristics compared with each other and with the intact UCL. Although not statistically significant, the reconstructions fixated at 30° more closely resembled the biomechanical characteristics of the intact elbow than did reconstructions fixated at 90°. No statistically significant difference was found in comparing the docking technique of UCL reconstruction with graft fixation at 30° vs. 90° of elbow flexion. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

The morphologic change of the ulnar collateral ligament of elbow in high school baseball pitchers, with and without symptoms, by sonography.

PubMed

Tajika, Tsuyoshi; Yamamoto, Atsushi; Oya, Noboru; Ichinose, Tsuyoshi; Shimoyama, Daisuke; Sasaki, Tsuyoshi; Shitara, Hitoshi; Kitagawa, Takanori; Saito, Kenichi; Osawa, Takashi; Takagishi, Kenji

2016-08-01

Few reports in the literature relate morphologic changes of the ulnar collateral ligament (UCL) to prior elbow symptoms. This study used ultrasonography (US) to assess the ulnohumeral joint space width, with and without stress, and elucidate morphologic changes of the UCL of the elbow in high school pitchers with and without a history of elbow symptoms. Each of 122 high school baseball pitchers who underwent US of the medial aspect of both elbows completed a self-administered questionnaire related to the self-satisfaction score (0-100) for pitching performance and throwing-related elbow joint pain sustained during the prior 3 years. We conducted gravity stress US elbow examination with 30° of flexion with and without valgus stress. Comparisons of the UCL thickness and ulnohumeral joint space width, with and without valgus stress, were made among the 122 high school pitchers with and without a history of elbow symptoms. Pitchers with an elbow symptom history exhibited a greater difference between the UCL thickness on the throwing side than those with no elbow symptom history (P = .0013). A negative significant association was found between UCL thickness on the pitching side and the self-evaluation score for pitching performance (r = -0.20, P = .04). US assessment demonstrated that the UCL in the dominant side with elbow symptom history was thicker than that with no elbow symptom history. The UCL thickness might reflect the prior pitching condition of high school baseball pitchers. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Impingement of Droplets in 60 Deg Elbows with Potential Flow

NASA Technical Reports Server (NTRS)

Hacker, Paul T.; Saper, Paul G.; Kadow, Charles F.

1956-01-01

Trajectories were determined for water droplets or other aerosol particles in air flowing through 600 elbows especially designed for two-dimensional potential motion. The elbows were established by selecting as walls of each elbow two streamlines of a flow field produced by a complex potential function that establishes a two-dimensional flow around. a 600 bend. An unlimited number of elbows with slightly different shapes can be established by selecting different pairs of streamlines as walls. Some of these have a pocket on the outside wall. The elbows produced by the complex potential function are suitable for use in aircraft air-inlet ducts and have the following characteristics: (1) The resultant velocity at any point inside the elbow is always greater than zero but never exceeds the velocity at the entrance. (2) The air flow field at the entrance and exit is almost uniform and rectilinear. (3) The elbows are symmetrical with respect to the bisector of the angle of bend. These elbows should have lower pressure losses than bends of constant cross-sectional area. The droplet impingement data derived from the trajectories are presented along with equations so that collection efficiency, area, rate, and distribution of droplet impingement can be determined for any elbow defined by any pair of streamlines within a portion of the flow field established by the complex potential function. Coordinates for some typical streamlines of the flow field and velocity components for several points along these streamlines are presented in tabular form. A comparison of the 600 elbow with previous calculations for a comparable 90 elbow indicated that the impingement characteristics of the two elbows were very similar.

Physical examination of the athlete's elbow.

PubMed

Hsu, Stephanie H; Moen, Todd C; Levine, William N; Ahmad, Christopher S

2012-03-01

Elbow injury is encountered less frequently than are other joint conditions. The bony architecture, muscle, ligament, and nerve anatomy are complex, and the forces leading to injury in the athlete's elbow are unique. Appreciating the pathomechanics leading to injury and a detailed knowledge of elbow anatomy are the foundation for conducting a directed history and physical examination that achieves an accurate diagnosis. Recent advances in physical examination have improved our ability to accurately diagnose and treat athletic elbow disorders. This article reviews general and focused physical examination maneuvers of the elbow in a systematic anatomic fashion.

Common extensor origin release in recalcitrant lateral epicondylitis - role justified?

PubMed Central

2010-01-01

The aim of our study was to analyse the efficacy of operative management in recalcitrant lateral epicondylitis of elbow. Forty patients included in this study were referred by general practitioners with a diagnosis of tennis elbow to the orthopaedic department at a district general hospital over a five year period. All had two or more steroid injections at the tender spot, without permanent relief of pain. All subsequently underwent simple fasciotomy of the extensor origin. Of forty patients thirty five had improvement in pain and function, two had persistent symptoms and three did not perceive any improvement. Twenty five had excellent, ten had well, two had fair and three had poor outcomes (recurrent problem; pain at rest and night). Two patients underwent revision surgery. Majority of the patients had improvement in pain and function following operative treatment. In this study, an extensor fasciotomy was demonstrated to be an effective treatment for refractory chronic lateral epicondylitis; however, further studies are warranted. PMID:20459701

An Epidemiological Comparison of Elbow Injuries Among United States High School Baseball and Softball Players, 2005-2006 Through 2014-2015.

PubMed

Pytiak, Andrew V; Kraeutler, Matthew J; Currie, Dustin W; McCarty, Eric C; Comstock, R Dawn

Pitching is a common mechanism of injury in baseball, with known risk factors for elbow injuries among adolescent pitchers. Elbow injury rates and mechanisms will differ between high school baseball and softball players. Descriptive epidemiology study. Level 3. Baseball- and softball-related injury data from the 2005-2006 through 2014-2015 academic years were collected from the High School Reporting Information Online (RIO) Internet-based data collection tool. Athlete-exposure (AE) and injury data were collected by certified athletic trainers. Rate ratios (RRs) were calculated comparing injury rates in the 2 populations. Injury proportion ratios (IPRs) comparing elbow injuries in pitchers and nonpitchers were calculated as the proportion of all elbow injuries in pitchers divided by the proportion of all elbow injuries in nonpitchers. A total of 214 elbow injuries in male baseball players occurred over 2,327,774 AEs, for an overall elbow injury rate of 0.92 per 10,000 AEs. A total of 75 elbow injuries were reported in female softball players over 1,731,644 AEs, for an overall rate of 0.43 per 10,000 AEs. The rate of elbow injury was significantly higher for baseball than softball (RR, 2.12; 95% CI, 1.64-2.77). A significantly greater proportion of elbow injuries in baseball were pitching-related compared with those from softball, with 50.2% occurring while pitching in baseball versus 11.0% in softball (IPR, 4.58; 95% CI, 2.35-8.93). If all injuries occurring during pitching were removed from both sports, the difference in elbow injury rate for baseball and softball would no longer be significant (RR, 1.19; 95% CI, 0.88-1.62). The rate of elbow injuries is significantly higher in baseball than softball. This is attributable to differences in rates of pitching-related injuries between these 2 groups. These results demonstrate that overhand pitching increases risk of elbow injury in high school athletes.

Inferring nonlinear mantle rheology from the shape of the Hawaiian swell.

PubMed

Asaadi, N; Ribe, N M; Sobouti, F

2011-05-26

The convective circulation generated within the Earth's mantle by buoyancy forces of thermal and compositional origin is intimately controlled by the rheology of the rocks that compose it. These can deform either by the diffusion of point defects (diffusion creep, with a linear relationship between strain rate and stress) or by the movement of intracrystalline dislocations (nonlinear dislocation creep). However, there is still no reliable map showing where in the mantle each of these mechanisms is dominant, and so it is important to identify regions where the operative mechanism can be inferred directly from surface geophysical observations. Here we identify a new observable quantity--the rate of downstream decay of the anomalous seafloor topography (swell) produced by a mantle plume--which depends only on the value of the exponent in the strain rate versus stress relationship that defines the difference between diffusion and dislocation creep. Comparison of the Hawaiian swell topography with the predictions of a simple fluid mechanical model shows that the swell shape is poorly explained by diffusion creep, and requires a dislocation creep rheology. The rheology predicted by the model is reasonably consistent with laboratory deformation data for both olivine and clinopyroxene, suggesting that the source of Hawaiian lavas could contain either or both of these components.

Risk of nerve injury during arthroscopy portal placement in the elbow joint: A cadaveric study

PubMed Central

Chaware, Prashant N; Santoshi, John A; Pakhare, Abhijit P; Rathinam, Bertha A D

2016-01-01

Background: Elbow arthroscopy has become a routine procedure now. However, placing portals is fraught with dangers of injuring the neurovascular structures around elbow. There are not enough data documenting the same amongst the Indians. We aimed to determine the relative distances of nerves around the elbow to the arthroscopy portals and risk of injury in different positions of the elbow. Materials and Methods: Six standard elbow arthroscopy portals were established in 12 cadaveric upper limbs after joint distension. Then using standard dissection techniques all the nerves around the elbow were exposed, and their distances from relevant portals were measured using digital vernier caliper in 90° elbow flexion and 0° extension. Descriptive statistical analysis was used for describing distance of the nerves from relevant portal. Wilcoxon-signed rank test and Friedman's test were used for comparison. Results: There was no major nerve injury at all the portals studied in both positions of the elbow. The total incidence of cutaneous nerve injury was 8.3% (12/144); medial cutaneous nerve of forearm 10/48 and posterior cutaneous nerve of forearm 2/24. No significant changes were observed in the distance of a nerve to an individual portal at 90° flexion or 0° extension position of the elbow. Conclusion: This study demonstrates the risk of injury to different nerves at the standard portals of elbow arthroscopy. In practice, the actual incidence of nerve injury may still be lower. We conclude that elbow arthroscopy is a safe procedure when all precautions as described are duly followed. PMID:26952128

Elbow arthroscopy.

PubMed

Dodson, Christopher C; Nho, Shane J; Williams, Riley J; Altchek, David W

2008-10-01

Arthroscopy of the elbow was originally considered to be an unsafe procedure because of the small size of the elbow joint capsule and its proximity to several crucial neurovascular structures. Over the past decade, however, the procedure has become safer and more effective. These improvements can be attributed to a better understanding of elbow anatomy and of the disorders about the elbow as well as to advances in arthroscopic equipment and surgical technique. The most common indications for elbow arthroscopy include removal of loose bodies, synovectomy, débridement and/or excision of osteophytes, capsular release, and the assessment and treatment of osteochondritis dissecans. More recent advances have expanded the indications of elbow arthroscopy to include fracture management (eg, radial head fractures) and the treatment of lateral epicondylitis.

Cutaneous lupus erythematosus of elbows: A distinct entity?

PubMed

Singh, Nidhi; Chandrashekar, Laxmisha; Kumar, Nava; Kar, Rakhee; Sylvia, Mary Theresa; Thappa, Devinder Mohan

2016-01-01

The elbow is not recognized as common site for cutaneous lupus erythematosus (CLE) lesions. Twelve cases of CLE over the elbows were evaluated for systemic involvement and Cutaneous Lupus Disease Area and Severity Index activity and damage scores and Systemic Lupus Erythematosus Disease Activity Index scoring was done. Histopathological examination of the affected skin was performed in doubtful cases. Most of the patients were women (10, 83.3%) with mean age of 28.75 years. Three patients had only elbow lesions and the remaining nine patients had CLE lesions at sites other than the elbows, of which five had elbow lesions preceding skin lesions elsewhere over the body and three patients were not aware of whether elbow lesions preceded or succeeded CLE lesions at other sites, and one patient had noticed malar rash 9 months prior to elbow lesions. All the patients antinuclear antibody positivity, systemic involvement, and fulfilled criteria for systemic lupus erythematosus. This peculiar localization of CLE to the elbows may be associated with a greater risk of systemic involvement and may be an predictor of flare of LE.

Mechanisms of strain accommodation in plastically-deformed zircon under simple shear deformation conditions during amphibolite-facies metamorphism

NASA Astrophysics Data System (ADS)

Kovaleva, Elizaveta; Klötzli, Urs; Wheeler, John; Habler, Gerlinde

2018-02-01

This study documents the strain accommodation mechanisms in zircon under amphibolite-facies metamorphic conditions in simple shear. Microstructural data from undeformed, fractured and crystal-plastically deformed zircon crystals are described in the context of the host shear zone, and evaluated in the light of zircon elastic anisotropy. Our work challenges the existing model of zircon evolution and shows previously undescribed rheological characteristics for this important accessory mineral. Crystal-plastically deformed zircon grains have axis oriented parallel to the foliation plane, with the majority of deformed grains having axis parallel to the lineation. Zircon accommodates strain by a network of stepped low-angle boundaries, formed by switching between tilt dislocations with the slip systems <100>{010} and < 1 bar 10>{110} and rotation axis [001], twist dislocations with the rotation axis [001], and tilt dislocations with the slip system <100>{001} and rotation axis [010]. The slip system < 1 bar 10>{110} is newly described for zircon. Most misorientation axes in plastically-deformed zircon grains are parallel to the XY plane of the sample and have [001] crystallographic direction. Such behaviour of strained zircon lattice is caused by elastic anisotropy that has a direct geometric control on the rheology, deformation mechanisms and dominant slip systems in zircon. Young's modulus and P wave velocity have highest values parallel to zircon [001] axis, indicating that zircon is elastically strong along this direction. Poisson ratio and Shear modulus demonstrate that zircon is also most resistant to shearing along [001]. Thus, [001] axis is the most common rotation axis in zircon. The described zircon behaviour is important to take into account during structural and geochronological investigations of (poly)metamorphic terrains. Geometry of dislocations in zircon may help reconstructing the geometry of the host shear zone(s), large-scale stresses in the crust, and, possibly, the timing of deformation, if the isotopic systems of deformed zircon were reset.

Epidemiology of shoulder and elbow pain in youth baseball players.

PubMed

Matsuura, Tetsuya; Suzue, Naoto; Iwame, Toshiyuki; Arisawa, Kokichi; Fukuta, Shoji; Sairyo, Koichi

2016-01-01

There are relatively few published epidemiological studies examining the differences in the risk of shoulder and elbow pain in young baseball players. The purpose of this study was to investigate risk factors for shoulder and elbow pain in child and adolescent baseball players. A total of 1563 players aged 7 to 12 years participated in this investigation. Subjects were asked whether they had experienced episodes of shoulder or elbow pain. We investigated the following risk factors for shoulder and elbow pain: age, position, years of baseball experience, and training hours per week. Data from the groups with and without shoulder and elbow pain were analyzed using multivariate logistic regression models. Among the 1563 participants, 15.9% and 29.2% reported episodes of shoulder and elbow pain, respectively. Multivariate analysis showed that shoulder pain was associated with age 10, 11, and 12 years, and that elbow pain was associated with age 10, 11, and 12 years, playing catcher, and >2 years of baseball experience. Training hours per week were not associated with either shoulder or elbow pain. In over 1000 baseball players aged 7 to 12 years, 15.9% reported episodes of shoulder pain, while 29.2% reported elbow pain in the throwing arm. The associated risk factors were different for each type of pain. Shoulder pain was associated with increased age while elbow pain was associated with increased age, increased years of baseball experience, and playing catcher.

A randomized controlled trial of nonoperative treatment versus open reduction and internal fixation for stable, displaced, partial articular fractures of the radial head: the RAMBO trial

PubMed Central

2014-01-01

Background The choice between operative or nonoperative treatment is questioned for partial articular fractures of the radial head that have at least 2 millimeters of articular step-off on at least one radiograph (defined as displaced), but less than 2 millimeter of gap between the fragments (defined as stable) and that are not associated with an elbow dislocation, interosseous ligament injury, or other fractures. These kinds of fractures are often classified as Mason type-2 fractures. Retrospective comparative studies suggest that operative treatment might be better than nonoperative treatment, but the long-term results of nonoperative treatment are very good. Most experts agree that problems like reduced range of motion, painful crepitation, nonunion or bony ankylosis are infrequent with both nonoperative and operative treatment of an isolated displaced partial articular fracture of the radial head, but determining which patients will have problems is difficult. A prospective, randomized comparison would help minimize bias and determine the balance between operative and nonoperative risks and benefits. Methods/Design The RAMBO trial (Radial Head – Amsterdam – Amphia – Boston - Others) is an international prospective, randomized, multicenter trial. The primary objective of this study is to compare patient related outcome defined by the ‘Disabilities of Arm, Shoulder and Hand (DASH) score’ twelve months after injury between operative and nonoperative treated patients. Adult patients with partial articular fractures of the radial head that comprise at least 1/3rd of the articular surface, have ≥ 2 millimeters of articular step-off but less than 2 millimeter of gap between the fragments will be enrolled. Secondary outcome measures will be the Mayo Elbow Performance Index (MEPI), the Oxford Elbow Score (OES), pain intensity through the ‘Numeric Rating Scale’, range of motion (flexion arc and rotational arc), radiographic appearance of the fracture (heterotopic ossification, radiocapitellar and ulnohumeral arthrosis, fracture healing, and signs of implant loosening or breakage) and adverse events (infection, nerve injury, secondary interventions) after one year. Discussion The successful completion of this trial will provide evidence on the best treatment for stable, displaced, partial articular fractures of the radial head. Trial registration The trial is registered at the Dutch Trial Register: NTR3413. PMID:24885637

[Efficacies of arthroscopic debridement and olecranon fossa plasty in the treatment of osteoarthritis and posterior elbow impingement].

PubMed

Liu, Yu-jie; Wang, Jun-liang; Li, Hai-feng; Qi, Wei; Wang, Ning

2012-07-17

To evaluate the efficacies of arthroscopic debridement and removal of osteophyma for olecroanon and olecranon fossa plasty for posterior impingement of elbow joint. Between 1999 and 2008, a total of 21 cases were diagnosed with osteoarthritis and posterior elbow impingement. There were 15 males and 6 females. And there were 16 right and 15 left cases. They included volleyball players (n = 7), tennis players (n = 7), golf enthusiasts (n = 4) and fencers (n = 3). The average duration of onset-operation was 3.5 years (range: 2.5 - 8). Arthroscopic exploration revealed synovial hyperplasia hypertrophy, cartilage degeneration and olecranon fossa hyperplasia with deformed olecranon fossa. Debridement and plasty were performed. Loose bodies were removed from elbow joint in 6 patients. Partial resection of posterior olecranon tip was performed and osteophytes or fibrous tissue removed in this area. Dynamic observation showed no posterior elbow impingement. Postoperative follow-up was conducted in 19 cases and 2 cases became lost to follow-up. The average follow-up period was 25.3 months (range: 18 - 42). All patients were evaluated preoperatively and postoperatively with the Hospital for Special Surgery Elbow Assessment Scale. The outcomes were excellent (n = 12), good (n = 7) and fair (n = 2). Postoperative patients elbow swelling and pain relieve, sports and life function returns to normal, elbow flexion and rotating mobility obviously improved. With the elbow radiological films to measure the range of motion, the average range of motion was 90.5° preoperatively and improved to 130° postoperatively. There was significant improvement in all cases. Posterior elbow impingement is caused by hyperextension trauma and elbow overuse during specific sporting activities. Arthroscopic debridement and olecroanon or olecranon fossa plasty demonstrates excellent results for posterior impingement of elbow joint.

Characteristics and prognosis of medial epicondylar fragmentation of the humerus in male junior tennis players.

PubMed

Harada, Mikio; Takahara, Masatoshi; Maruyama, Masahiro; Takagi, Michiaki

2014-10-01

Although medial epicondylar fragmentation of the humerus is a reported elbow injury in junior tennis players, there have been only a few studies on this entity, and none have investigated the characteristics and prognosis of medial epicondylar fragmentation. Forty-one male junior tennis players, aged 11 to 14 years (mean, 13 years), underwent elbow examination by ultrasonography. Elbow re-examination was performed in subjects with medial epicondylar fragmentation at an average of 20 months (12-30 months) after the initial examination. On examination, 9 subjects (22%) had elbow pain. Ultrasonography showed that 6 subjects (15%) had medial epicondylar fragmentation, all of whom had elbow pain. Medial epicondylar fragmentation was present in 5 (38%) of 13 subjects aged 11 to 12 years and in 1 (4%) of 28 aged 13 to 14 years. More subjects aged 11 to 12 years had medial epicondylar fragmentation (P = .0084). All 6 subjects with medial epicondylar fragmentation continued to play tennis between the initial elbow examination and the re-examination. At re-examination, although ultrasonography showed that 5 developed bone union and 1 had nonunion, 3 subjects (50%) reported elbow pain. Our results demonstrated that subjects aged 11 to 12 years had a high frequency (38%) of medial epicondylar fragmentation. Although medial epicondylar fragmentation was the main cause of elbow pain (67%) at the initial elbow examination, all 6 players with medial epicondylar fragmentation continued to play tennis between the initial elbow examination and the re-examination. At re-examination, 5 subjects presented spontaneous bone union (83%), but 3 subjects (50%) reported elbow pain. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Prevalence and inheritance of and selection for elbow arthrosis in Bernese mountain dogs and Rottweilers in Sweden and benefit: cost analysis of a screening and control program.

PubMed

Swenson, L; Audell, L; Hedhammar, A

1997-01-15

To determine the prevalence and charges over time in the prevalence of elbow arthrosis in Bernese Mountain Dogs and Rottweilers, to ascertain whether prevalence or severity of elbow arthrosis was associated with sex of the dogs, age at the time of elbow joint examination, or ancestral background, to determine the effects of selective breeding, and to conduct an economic evaluation of the elbow arthrosis program operated by the Swedish Kennel Club. Analysis of radiographic evaluations of elbow joint conformity. 4,515 dogs from 2 breeds registered by the Swedish Kennel Club. All radiographs were scrutinized by a single radiologist (LA), and elbow joint conformation was classified as normal or arthrotic, with the degree of arthrosis classified as 1, 2, or 3. Decreasing prevalence of elbow arthrosis corresponding to selection of breeding stock and high heritabilities was found. Sex differences were documented in both breeds, but with contradictory directions. This was interpreted as breed differences in the distribution of genes related to elbow arthrosis. Economic analyses showed that costs of screening and registration of elbow joints was less than the value of dogs estimated to have been saved from moderate and severe elbow arthrosis in both breeds. Documented effects of age suggest that all dogs should be screened at the same age, rather than screening a few dogs at an older, more revealing age. In screening and control programs based on an open registry with access to family records, decreasing prevalence of elbow arthrosis can be expected, and related to selection of breeding stock.

Feasibility of four-dimensional preoperative simulation for elbow debridement arthroplasty.

PubMed

Yamamoto, Michiro; Murakami, Yukimi; Iwatsuki, Katsuyuki; Kurimoto, Shigeru; Hirata, Hitoshi

2016-04-02

Recent advances in imaging modalities have enabled three-dimensional preoperative simulation. A four-dimensional preoperative simulation system would be useful for debridement arthroplasty of primary degenerative elbow osteoarthritis because it would be able to detect the impingement lesions. We developed a four-dimensional simulation system by adding the anatomical axis to the three-dimensional computed tomography scan data of the affected arm in one position. Eleven patients with primary degenerative elbow osteoarthritis were included. A "two rings" method was used to calculate the flexion-extension axis of the elbow by converting the surface of the trochlea and capitellum into two rings. A four-dimensional simulation movie was created and showed the optimal range of motion and the impingement area requiring excision. To evaluate the reliability of the flexion-extension axis, interobserver and intraobserver reliabilities regarding the assessment of bony overlap volumes were calculated twice for each patient by two authors. Patients were treated by open or arthroscopic debridement arthroplasties. Pre- and postoperative examinations included elbow range of motion measurement, and completion of the patient-rated questionnaire Hand20, Japanese Orthopaedic Association-Japan Elbow Society Elbow Function Score, and the Mayo Elbow Performance Score. Measurement of the bony overlap volume showed an intraobserver intraclass correlation coefficient of 0.93 and 0.90, and an interobserver intraclass correlation coefficient of 0.94. The mean elbow flexion-extension arc significantly improved from 101° to 125°. The mean Hand20 score significantly improved from 52 to 22. The mean Japanese Orthopaedic Association-Japan Elbow Society Elbow Function Score significantly improved from 67 to 88. The mean Mayo Elbow Performance Score significantly improved from 71 to 91 at the final follow-up evaluation. We showed that four-dimensional, preoperative simulation can be generated by adding the rotation axis to the one-position, three-dimensional computed tomography image of the affected arm. This method is feasible for elbow debridement arthroplasty.

Evaluation of common elbow pathologies: a focus on physical examination.

PubMed

Laratta, Joseph; Caldwell, Jon-Michael; Lombardi, Joseph; Levine, William; Ahmad, Christopher

2017-05-01

Elbow tendinopathy accounts for the majority of elbow pathology in patients presenting to upper extremity and sports medicine surgeons. With increased participation in overhead sports in an aging population, the incidence of elbow injuries has risen. A comprehensive knowledge of elbow anatomy and biomechanical function of the elbow complex is prerequisite in the assessment of patients with elbow injuries; however, a thorough understanding of alternative and confounding pathologies is essential for accurate diagnosis. Because tendinopathy, tendonitis, and tendon tears have an anatomic basis for their pathology, a targeted history and meticulous physical examination often yields an accurate clinical diagnosis. The importance of physical examination and provocative examination maneuvers must be stressed in a technologically advanced era where clinical diagnosis is too commonly attained solely by advanced imaging modalities. A revived dedication to the physical examination may enhance our ability to correctly diagnose various pathologies about the elbow. Early and accurate clinical diagnosis is the first step in the proper initiation of treatment modalities and improvement in overall patient outcome.

Articular Contact Area and Pressure in Posteromedial Rotatory Instability of the Elbow.

PubMed

Bellato, Enrico; Fitzsimmons, James S; Kim, Youngbok; Bachman, Daniel R; Berglund, Lawrence J; Hooke, Alexander W; O'Driscoll, Shawn W

2018-03-21

Joint incongruity in posteromedial rotatory instability (PMRI) has been theorized to determine early articular degenerative changes. Our hypothesis was that the articular contact area and contact pressure differ significantly between an intact elbow and an elbow affected by PMRI. Seven cadaveric elbows were tested under gravity varus stress using a custom-made machine designed to simulate muscle loads and allow passive elbow flexion (0° to 90°). The mean contact area and contact pressure data were collected and processed using the Tekscan sensor and software. After testing the intact specimen (intact elbow), a PMRI injury was simulated (PMRI elbow) and the specimen was tested again. The PMRI elbows were characterized by initial joint subluxation and significantly elevated articular contact pressure. Both worsened, corresponding with a reduction in contact area, as the elbow was flexed from 0° until the joint subluxation and incongruity spontaneously reduced (at a mean [and standard error] of 60° ± 5° of flexion), at which point the mean contact pressure decreased from 870 ± 50 kPa (pre-reduction) to 440 ± 40 kPa (post-reduction) (p < 0.001) and the mean contact area increased from 80 ± 8 mm to 150 ± 58 mm (p < 0.001). This reduction of the subluxation was also followed by a shift of the contact area from the coronoid fracture edge toward the lower portion of the coronoid. At the flexion angle at which the PMRI elbows reduced, both the contact area and the contact pressure of the intact elbows differed significantly from those of the PMRI elbows, both before and after the elbow reduction (p < 0.001). The reduction in contact area and increased contact pressures due to joint subluxation and incongruity could explain the progressive arthritis seen in some elbows affected by PMRI. This biomechanical study suggests that the early degenerative changes associated with PMRI reported in the literature could be subsequent to joint incongruity and an increase in contact pressure between the coronoid fracture surface and the trochlea.

Multiple forearm robotic elbow configuration

DOEpatents

Fisher, John J.

1990-01-01

A dual forearmed robotic elbow configuration comprises a main arm having a double elbow from which two coplanar forearms depend, two actuators carried in the double elbow for moving the forearms, and separate, independent end effectors, operated by a cable carried from the main arm through the elbow, is attached to the distal end of each forearm. Coiling the cables around the actuators prevents bending or kinking when the forearms are rotated 360 degrees. The end effectors can have similar or different capabilities. Actuator cannisters within the dual elbow are modular for rapid replacement or maintenance. Coarse and fine resolver transducers within the actuators provide accurate position referencing information.

Pressure loss in elbow pipes of unplasticized polyvinyl chloride.

PubMed

Iwasaki, T; Ojima, J

1996-01-01

In the ductwork of local exhaust systems, 90 degrees elbow pipes (JIS K 6739) are commonly used to alter the direction of airflow; thus, are important components of polyvinyl chloride (PVC) ducts. Pressure loss in 90 degrees PVC elbow pipes was investigated by measuring static pressure, and the characteristics of airflow was determined. First, a linear decrease in static pressure was observed at points of the downstream side beyond a distance of 10 times the diameter (10d) from the flanged round opening of the smooth VU ducts (JIS K6741). The linear decrease was also observed at points of the downstream side located at distances of greater than 30d from the elbow pipe. Coefficients of loss in the PVC elbow pipes were found to be constant for the Reynolds numbers ranging from 3.38 x 10(4) to 5.96 x 10(5) for all diameters examined, and a chart of pressure loss was constructed with these coefficients. The coefficients of loss in PVC elbow pipes were not equivalent to those of metal stamped elbows for any R/d. However, the differences in the coefficients between the metal stamped elbow and the PVC elbow were smaller with larger R/d values.

Elbow Injuries in Professional Baseball: Epidemiological Findings From the Major League Baseball Injury Surveillance System.

PubMed

Ciccotti, Michael G; Pollack, Keisha M; Ciccotti, Michael C; D'Angelo, John; Ahmad, Christopher S; Altchek, David; Andrews, James; Curriero, Frank C

2017-08-01

Elbow injuries cause significant disability for the throwing athlete. Scant data are available on the distribution and characteristics of these injuries in elite baseball players. No study exists that focuses solely on the epidemiological characteristics of elbow injuries in professional baseball players using a comprehensive injury surveillance system. Professional baseball players have a high occurrence of elbow injuries influenced by factors including length of time playing, time period within the annual baseball season, and specific position played. Descriptive epidemiological study. Data on elbow injuries occurring during the 2011-2014 seasons were collected from Major League Baseball's Health Injury and Tracking System, a comprehensive injury surveillance system. Each specific type of elbow injury was evaluated with respect to overall injury rate, years as a professional player, mechanism of injury, treatment, average time lost, and return to play. During the study period, 3185 elbow injuries (n = 430 Major League; n = 2755 Minor League) occurred. The mean number of days missed and percentage requiring surgery were similar between Major and Minor League players. Overall, 20.0% (650/3185) of the injuries required surgical treatment. Pitchers were the most likely to incur an elbow injury (40.0% of injured athletes were pitchers), were the most likely to require surgery (34.2% of injured pitchers required surgery), and had the greatest mean number of days missed when treated nonsurgically (33.2 days). Medial injuries composed 42.1% (1342/3185) of all elbow injuries. Of all elbow surgeries performed during the study period, the highest percentage involved ligaments (372/650; 57.2%). Elbow injuries are a considerable source of disability in professional baseball players. Pitchers are most likely to incur these injuries, are most likely to require surgery, and have the highest mean number of days missed when treated nonsurgically. The most common injuries involve the medial elbow, with ligament injuries most often requiring surgery. This study represents the only investigation to date using a comprehensive injury surveillance system to examine elbow injuries in professional baseball players. It provides a basis for injury prevention and treatment recommendations, establishes the most thorough framework for determining elbow injury risk, and focuses continued research on elbow injury prevention in the elite baseball player.

Fracture toughness of materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burns, S.J.

Crack tip dislocation emission in bulk specimens have been measured in single crystal specimens and the measurements are well below the accepted theoretical values for dislocation emission. The image forces on a dislocation due to the presence of a semi-infinite crack are used to calculate the potential energy of the dislocation around the crack. Expressions for the radial and tangential forces and for slip and climb forces have been found. Crack tip deformation in Mode I and Mode II fractures on both {l brace}100{r brace} and {l brace}110{r brace} planes have been observed in crystals of LiF. The deformation ismore » shown to nearly completely shield {l brace}110{r brace} plane cracks and prevent their propagation while deformation is less effective in shielding {l brace}100{r brace} plane cracks. The fracture toughness of MgO-partially-stabilized ZrO{sub 2} exhibiting transformation toughening been measured. The equations of linear elastic fracture mechanics have been self-consistantly formulated to include the residual displacement from the transformation wake. MgO single crystals were fatigued in plastic strain control at elevated temperatures. At high temperatures, dense bundles of dislocations were observed in transmission electron microscopy aligned perpendicular to the Burgers' vector directions. The thermodynamics of a superconducting second order phase transformation has been related to jumps in physical properties. A simple energy balance, without assuming an equation of state, is used to relate the rate of change of state variables to measurable physical properties. There are no preconceived assumptions about the superconducting mechanism.« less

Analysis of elbow muscle strength parameters in Brazilian jiu-jitsu practitioners.

PubMed

Follmer, Bruno; Dellagrana, Rodolfo André; de Lima, Luis Antonio Pereira; Herzog, Walter; Diefenthaeler, Fernando

2017-12-01

Upper-body dynamic and isometric maximum strength are essential components for success in Brazilian jiu-jitsu (BJJ). This study was aimed at analysing strength parameters in the elbow flexor and extensor muscles of BJJ practitioners. Participants (n = 28) performed maximum isometric contractions of elbow flexors and extensors to determine peak torque (PT), rate of force development (RFD), and the torque-angle (T-A) relationship at elbow angles of 45°, 60°, 75°, 90°, 105°, and 120°. Additionally, concentric and eccentric PTs were measured at 1.04 rad·s -1 . Student t-test and ANOVA were performed using α = 0.05. Elbow flexors were stronger isometrically (P < 0.001, ES = 1.23) but weaker concentrically (P < 0.05, ES = 0.54) than extensor muscles, possibly because of the extensive grip disputes and pushing of opponents in BJJ. The T-A relationship had an inverted "U"-shape. Torque differences across elbow angles were moderate (ES = 0.62) for the extensor and large (ES = 0.92) for the flexor muscles. Isometric torque was greatest for elbow angles of 105° and 75° and smallest for 45° and 120° for extensor and flexor muscles, respectively. Elbow flexors had a greater RFD than extensors, regardless of elbow angle. The present study provides comprehensive results for elbow muscle strength in BJJ practitioners.

Modelling Thin Film Microbending: A Comparative Study of Three Different Approaches

NASA Astrophysics Data System (ADS)

Aifantis, Katerina E.; Nikitas, Nikos; Zaiser, Michael

2011-09-01

Constitutive models which describe crystal microplasticity in a continuum framework can be envisaged as average representations of the dynamics of dislocation systems. Thus, their performance needs to be assessed not only by their ability to correctly represent stress-strain characteristics on the specimen scale but also by their ability to correctly represent the evolution of internal stress and strain patterns. In the present comparative study we consider the bending of a free-standing thin film. We compare the results of 3D DDD simulations with those obtained from a simple 1D gradient plasticity model and a more complex dislocation-based continuum model. Both models correctly reproduce the nontrivial strain patterns predicted by DDD for the microbending problem.

A new fiber sensor based on graphene coating technique for wearable equipment

NASA Astrophysics Data System (ADS)

Wu, Ensen; Zhang, Jinnan; Qiao, Min; Cao, Yanghua; Wang, Qi; Ren, Xiaomin; Zuo, Yong

2018-02-01

We propose and implement a graphene-based composite fiber sensor in this paper. The advantages of this composite fiber lie in simple and practicable fabrication, high sensitivity to tensile strain deformation, wide maximal sensing range. The experiment shows that the composite fiber can monitor small signals of the body and massive movements in conventionality condition such as human pulse and the movement of elbow. This suggests that this graphene-based composite fiber has a broad prospect in health monitoring and movement recognition.

Pulled elbow in children.

PubMed

Yamanaka, Syunsuke; Goldman, Ran D

2018-06-01

Question Our practice is seeing children with relatively minor injuries to their elbows, with a history of "swinging" them when their hands are being held to cross the road. Nothing is usually found on a physical examination. I know that this is likely a "pulled elbow." Can we manage this in the clinic setting rather than sending the family to the emergency department? What would be the best course of action in the clinic setting? Answer Pulled elbow, also called nursemaid's elbow , is a radial head subluxation caused by axial traction or a sudden pull of the extended pronated arm, and it is a very common phenomenon. The practice of swinging children while holding their hands should be abandoned. In the case of pulled elbow, the child usually avoids moving the affected arm, holding it close to his or her body, without considerable pain, and no obvious swelling or deformity can be seen. While a fracture should be excluded, pulled elbow can usually be identified based on this presentation. The reduction procedure can easily be done in the office setting, with an 80% success rate and no complications. The hyperpronation maneuver (holding the elbow at 90° and then firmly pronating the wrist) to reduce pulled elbow has been found to be better than a supination-flexion maneuver (holding the elbow at 90° with one hand, supinating and flexing the elbow rapidly with the other) and should be exercised first. When 2 trials of reduction are unsuccessful, the child's arm should be splinted and the family should be sent for further evaluation. Copyright© the College of Family Physicians of Canada.

Biomechanical Evaluation of Standard Versus Extended Proximal Fixation Olecranon Plates for Fixation of Olecranon Fractures.

PubMed

Boden, Allison L; Daly, Charles A; Dalwadi, Poonam P; Boden, Stephanie A; Hutton, William C; Muppavarapu, Raghuveer C; Gottschalk, Michael B

2018-01-01

Small olecranon fractures present a significant challenge for fixation, which has resulted in development of plates with proximal extension. Olecranon-specific plates with proximal extensions are widely thought to offer superior fixation of small proximal fragments but have distinct disadvantages: larger dissection, increased hardware prominence, and the increased possibility of impingement. Previous biomechanical studies of olecranon fracture fixation have compared methods of fracture fixation, but to date there have been no studies defining olecranon plate fixation strength for standard versus extended olecranon plates. The purpose of this study is to evaluate the biomechanical utility of the extended plate for treatment of olecranon fractures. Sixteen matched pairs of fresh-frozen human cadaveric elbows were used. Of the 16, 8 matched pairs received a transverse osteotomy including 25% and 8 including 50% of the articular surface on the proximal fragment. One elbow from each pair was randomly assigned to a standard-length plate, and the other elbow in the pair received the extended-length plate, for fixation of the fracture. The ulnae were cyclically loaded and subsequently loaded to failure, with ultimate load, number of cycles, and gap formation recorded. There was no statistically significant difference between the standard and extended fixation plates in simple transverse fractures at either 25% or 50% from the proximal most portion of the articular surface of the olecranon. Standard fixation plates are sufficient for the fixation of small transverse fractures, but caution should be utilized particularly with comminution and nontransverse fracture patterns.

Does Flooring Substrate Impact Kennel and Dog Cleanliness in Commercial Breeding Facilities?

PubMed Central

Stella, Judith; Hurt, Moriah; Bauer, Amy; Croney, Candace

2018-01-01

Simple Summary It is important to understand how the flooring substrate used in dog housing impacts dog health and well-being. Aspects to consider include paw, elbow, and hock health, the cleanliness of the dog, and the ability of the floors to be cleaned easily and thoroughly. This pilot study assessed the health and cleanliness of 118 dogs housed on three different types of flooring commonly found in commercial breeding kennels. No serious paw, elbow, or hock problems were identified. Thirty-one percent or fewer kennels at each facility were found to have fecal contamination after routine cleaning and the majority of dogs were clean. These findings indicate that a well-managed kennel can maintain clean, healthy dogs on different types of flooring substrates. Abstract Evaluation of kennel flooring surfaces is needed to understand their impacts on dog health and well-being. This pilot study aimed to characterize aspects of physical health, kennel cleanliness, and dog body cleanliness on flooring types common in US breeding kennels. Subjects were 118 adult dogs housed on diamond-coated expanded metal (DCEM), polypropylene (POLY), or concrete (CON) flooring at five commercial breeding facilities in Indiana, U.S. Body condition, paw, elbow, and hock health scores were recorded. Each indoor kennel and dog was visually assessed for cleanliness. Kennels were swabbed immediately after cleaning with electrostatic dry cloths and cultured for Escherichia coli. Descriptive statistics were used for analysis. Mean body condition score (BCS), kennel and dog cleanliness scores were all near ideal (3, 1.15, and 1.04, respectively). Thirty-one percent or fewer kennels at each facility were culture-positive for E. coli after cleaning. No serious paw, elbow, or hock problems were identified. Overall, the findings indicate that with appropriate management and regular access to additional surfaces, dog foot health, cleanliness, and kennel cleanliness can be maintained on the flooring types investigated. PMID:29690514

Inhalant abuse of 1,1-difluoroethane (DFE) leading to heterotopic ossification: a case report

PubMed Central

Little, Jill; Hileman, Barbara; Ziran, Bruce H

2008-01-01

Background Heterotopic ossification (HO) is the formation of mature, lamellar bone within soft tissues other than the periosteum. There are three recognized etiologies of HO: traumatic, neurogenic, and genetic. Presently, there are no definitively documented causal factors of HO. The following factors are presumed to place a patient at higher risk: 60 years of age or older, male, previous HO, hypertrophic osteoarthritis, ankylosing spondylitis, diffuse idiopathic skeletal hyperostosis, prior hip surgery, and surgical risk factors. Case presentation A 33-year-old male, involved in a motor vehicle crash, sustained an irreducible acetabulum fracture/dislocation, displaced proximal humerus fracture, and an impacted pilon fracture. During the time of injury, he was intoxicated from inhaling the aerosol propellant used in "dust spray" cans (1,1-difluoroethane, C2H4F2). Radiographs identified rapid pathologic bone formation about the proximal humeral metaphysis, proximal femur, elbow, and soft tissue several months following the initial injury. Discussion The patient did not have any genetic disorders that could have attributed to the bone formation but had some risk factors (male, fracture with dislocation). Surgically, the recommended precautions were followed to decrease the chance of HO. Although the patient did not have neurogenic injuries, the difluoroethane in dusting spray can cause damage to the central nervous system. Signals may have been mixed causing the patient's body to produce bone instead of tissue to strengthen the injured area. Conclusion What is unusual in this case is the rate at which the pathological bone formation appeared, which was long outside the 4–6 week window in which HO starts to appear. The authors are not certain as to the cause of this rapid formation but suspect that the patient's continued abuse of inhaled aerosol propellants may be the culprit. PMID:18973696

Inhalant abuse of 1,1-difluoroethane (DFE) leading to heterotopic ossification: a case report.

PubMed

Little, Jill; Hileman, Barbara; Ziran, Bruce H

2008-10-30

Heterotopic ossification (HO) is the formation of mature, lamellar bone within soft tissues other than the periosteum. There are three recognized etiologies of HO: traumatic, neurogenic, and genetic. Presently, there are no definitively documented causal factors of HO. The following factors are presumed to place a patient at higher risk: 60 years of age or older, male, previous HO, hypertrophic osteoarthritis, ankylosing spondylitis, diffuse idiopathic skeletal hyperostosis, prior hip surgery, and surgical risk factors. A 33-year-old male, involved in a motor vehicle crash, sustained an irreducible acetabulum fracture/dislocation, displaced proximal humerus fracture, and an impacted pilon fracture. During the time of injury, he was intoxicated from inhaling the aerosol propellant used in "dust spray" cans (1,1-difluoroethane, C2H4F2). Radiographs identified rapid pathologic bone formation about the proximal humeral metaphysis, proximal femur, elbow, and soft tissue several months following the initial injury. The patient did not have any genetic disorders that could have attributed to the bone formation but had some risk factors (male, fracture with dislocation). Surgically, the recommended precautions were followed to decrease the chance of HO. Although the patient did not have neurogenic injuries, the difluoroethane in dusting spray can cause damage to the central nervous system. Signals may have been mixed causing the patient's body to produce bone instead of tissue to strengthen the injured area. What is unusual in this case is the rate at which the pathological bone formation appeared, which was long outside the 4-6 week window in which HO starts to appear. The authors are not certain as to the cause of this rapid formation but suspect that the patient's continued abuse of inhaled aerosol propellants may be the culprit.

Early return to baseline range of motion and strength after anterior shoulder instability surgery: a Multicenter Orthopaedic Outcomes Network (MOON) shoulder group cohort study.

PubMed

Buckwalter V, Joseph A; Wolf, Brian R; Glass, Natalie; Bollier, Matt; Kuhn, John E; Hettrich, Carolyn M

2018-03-23

Patients often return to higher-level activities and sports at 4 to 8 months after anterior shoulder stabilization procedures. It is unknown what percentage of patients have regained normal function at this time frame and what factors predict residual deficits, range of motion (ROM), and strength after anterior shoulder instability surgery. Ten participating sites throughout the United States enrolled patients in a prospective cohort study including primary, revision, arthroscopic, and open anterior stabilization procedures. Baseline demographic data and patient outcomes questionnaires were collected with initial physical examination, treatment, surgical findings, and surgical repair details. At the 6-month follow-up visit, ROM and strength measurements were collected and compared with preoperative measurements. There were 348 patients identified who underwent surgical treatment for anterior shoulder instability. Of these, 259 patients (74.0%) returned to baseline, and 89 (26.0%) did not return to baseline shoulder ROM (≥20° loss of ROM) or strength. A higher Beighton score (P = .01) and number of dislocations (P < .01) were associated with failure to regain baseline ROM and strength at early follow-up. No surgical variables were found to influence return to baseline function, including open vs. arthroscopic surgery, primary vs. revision surgery, and number of suture anchors. By 4 to 8 months postoperatively, 76% of patients return to baseline ROM, 98% return to baseline strength, and 74% return to both baseline ROM and strength. An increased number of dislocations and generalized joint laxity were associated with failure to return to baseline ROM and strength at early follow-up after anterior shoulder instability surgery. Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Truly anatomic coracoclavicular ligament reconstruction with 2 Endobutton devices for acute Rockwood type V acromioclavicular joint dislocations.

PubMed

Xue, Cheng; Song, Li-Jun; Zhang, Hao; Tang, Guo-Long; Li, Xiang; Fang, Jia-Hu

2018-06-01

Truly anatomic coracoclavicular ligament reconstruction (TACCR) according to the original insertions is a creative new method for the treatment of severe acromioclavicular separation. This research analyzed the clinical and radiologic results of TACCR in 25 patients with at least 2-year follow-up. The study enrolled 25 patients with Rockwood type V acromioclavicular joint dislocations who underwent TACCR using 2 Endobutton (Smith & Nephew Inc., Andover, MA, USA) devices from May 2013 to October 2015. Patients were assessed with clinical and radiologic follow-up at 3, 6, 12, 18, and 24 months postoperatively. The clinical assessments consisted of the visual analog scale and the Constant score. The radiographic evaluations were performed by measurements of the coracoclavicular distance. The mean follow-up was 34 ± 6.8 months (range, 24-48 months). The visual analog scale and Constant scores revealed significant advancements from 5 ± 0.9 (range, 4-7) and 45 ± 5.6 (range, 30-54) scores preoperatively to 0 ± 0.5 (range, 0-2) and 95 ± 2.9 (range, 91-98) scores at 24 months postoperatively, respectively. The coracoclavicular distance significantly decreased from 23 ± 5.4 mm (range, 16-34 mm) preoperatively to 8 ± 0.9 mm (range, 7-10 mm) at the final follow-up. TACCR represents a safe, reliable and creative surgical technique that yields good to excellent clinical and radiologic outcomes in the treatment of severe acromioclavicular separation. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

A primer for physical examination of the elbow.

PubMed

Zouzias, Ioannis C; Byram, Ian R; Shillingford, Jamal N; Levine, William N

2012-02-01

The elbow is a complex joint consisting of 3 separate but important articulations: the ulnohumeral, radiohumeral, and proximal radioulnar joints. The elbow assists in positioning the hand in space through 2 important motions, flexion-extension and pronation-supination. Although the elbow is not a weightbearing joint, it is subjected to significant loads, especially in overhead and throwing athletes. An accurate knowledge of the anatomy and physiology of the elbow joint is critical for conducting a focused physical examination and arriving at an accurate diagnosis. The goal of this article is to review general and focused physical examination of the elbow in a systematic manner based on medial, lateral, anterior, and posterior aspects.

Medial elbow pain

PubMed Central

Barco, Raul; Antuña, Samuel A.

2017-01-01

Medial elbow pain is uncommon when compared with lateral elbow pain. Medial epicondylitis is an uncommon diagnosis and can be confused with other sources of pain. Overhead throwers and workers lifting heavy objects are at increased risk of medial elbow pain. Differential diagnosis includes ulnar nerve disorders, cervical radiculopathy, injured ulnar collateral ligament, altered distal triceps anatomy or joint disorders. Children with medial elbow pain have to be assessed for ‘Little League elbow’ and fractures of the medial epicondyle following a traumatic event. This paper is primarily focused on the differential diagnosis of medial elbow pain with basic recommendations on treatment strategies. Cite this article: EFORT Open Rev 2017;2:362-371. DOI: 10.1302/2058-5241.2.160006 PMID:28932488

Neurological Complications Related to Elective Orthopedic Surgery: Part 1: Common Shoulder and Elbow Procedures.

PubMed

Dwyer, Tim; Henry, Patrick D G; Cholvisudhi, Phantila; Chan, Vincent W S; Theodoropoulos, John S; Brull, Richard

2015-01-01

Many anesthesiologists are unfamiliar with the rate of surgical neurological complications of the shoulder and elbow procedures for which they provide local anesthetic-based anesthesia and/or analgesia. Part 1 of this narrative review series on neurological complications of elective orthopedic surgery describes the mechanisms and likelihood of peripheral nerve injury associated with some of the most common shoulder and elbow procedures, including open and arthroscopic shoulder procedures, elbow arthroscopy, and total shoulder and elbow replacement. Despite the many articles available, the overall number of studied patients is relatively low. Large prospective trials are required to establish the true incidence of neurological complications following elective shoulder and elbow surgery. As the popularity of regional anesthesia increases with the development of ultrasound guidance, anesthesiologists should have a thoughtful understanding of the nerves at risk of surgical injury during elective shoulder and elbow procedures.

21 CFR 888.3160 - Elbow joint metal/polymer semi-constrained cemented prosthesis.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Elbow joint metal/polymer semi-constrained cemented prosthesis. 888.3160 Section 888.3160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Elbow joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An elbow joint metal...

21 CFR 888.3180 - Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis. 888.3180 Section 888.3180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3180...

21 CFR 888.3180 - Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis. 888.3180 Section 888.3180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3180...

21 CFR 888.3180 - Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis. 888.3180 Section 888.3180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3180...

21 CFR 888.3180 - Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis. 888.3180 Section 888.3180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3180...

21 CFR 888.3180 - Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis. 888.3180 Section 888.3180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES ORTHOPEDIC DEVICES Prosthetic Devices § 888.3180...

Effect of single dose radiation therapy on weight-bearing lameness in dogs with elbow osteoarthritis.

PubMed

Kapatkin, Amy S; Nordquist, Barbro; Garcia, Tanya C; Griffin, Maureen A; Theon, Alain; Kim, Sun; Hayashi, Kei

2016-07-19

To determine if a single low dose of radiation therapy in dogs with osteoarthritis of the elbow joint was associated with a detectable improvement in their lameness and pain as documented by force platform gait analysis. In this cohort longitudinal observational study, five Labrador Retrievers with lameness due to elbow osteoarthritis that was unresponsive to medical treatment were removed from all non-steroidal anti-inflammatory and analgesic medications. A single treatment of radiation therapy delivering 10 Gray was performed on the affected elbow joint(s). Force platform gait analysis was used to assess the ground reaction forces of a limb affected with elbow osteoarthritis both before and after radiation therapy. Significant differences occurred in the weight-bearing on an affected limb with elbow osteoarthritis after radiation therapy at weeks six and 14. Change due to treatment was particularly apparent in dogs with unilateral elbow osteoarthritis. Administering a single low dose of radiation therapy may have a short-term benefit in dogs with elbow osteoarthritis, which is similar to the evidence supporting the use of radiation therapy in horses with orthopaedic disease.

Use of the Liverpool Elbow Score as a postal questionnaire for the assessment of outcome after total elbow arthroplasty.

PubMed

Ashmore, Alexander M; Gozzard, Charles; Blewitt, Neil

2007-01-01

The Liverpool Elbow Score (LES) is a newly developed, validated elbow-specific score. It consists of a patient-answered questionnaire (PAQ) and a clinical assessment. The purpose of this study was to determine whether the PAQ portion of the LES could be used independently as a postal questionnaire for the assessment of outcome after total elbow arthroplasty and to correlate the LES and the Mayo Elbow Performance Score (MEPS). A series of 51 total elbow replacements were reviewed by postal questionnaire. Patients then attended the clinic for assessment by use of both the LES and the MEPS. There was an excellent response rate to the postal questionnaire (98%), and 44 elbows were available for clinical review. Good correlation was shown between the LES and the MEPS (Spearman correlation coefficient, 0.84; P < .001) and between the PAQ portion of the LES and the MEPS (Spearman correlation coefficient, 0.76; P < .001). We conclude that there is good correlation between the LES PAQ component and the MEPS, suggesting that outcome assessment is possible by postal questionnaire.

Rehabilitation of patient with brachial plexus lesion and break in axillary artery. Case study.

PubMed

Bajuk, S; Jelnikar, T; Ortar, M

1996-01-01

This paper describes the physiotherapy and occupational therapy used in treating a 74-year-old woman with a left brachial plexus lesion, a break in the axillary artery, dislocation of the acromioclavicular joint, a broken scapula and clavicula, serial left rib fractures, and lacerations on the upper and lower arm. After testing the patient, the following goals were set: reduce pain, soften scar tissue, and improve joint motion, muscle strength, and functionality of the hand. A 12-month outpatient program was used. Various analgesics were used to reduce pain, and a special aid was made to unweight the shoulder and elbow joints. Physiotherapy included kinesiotherapy, audiovisual biofeedback, electrical stimulation, friction massage, and lymph drainage. Occupational therapy included active functional exercises and re-education. As a result of this program, the patient no longer had pain, passive range of motion was close to normal, active motion where present was improved, swelling was reduced, and the hand became functional again. Complex physiotherapy, occupational therapy, and the patient's motivation resulted in the rehabilitation of severe trauma of the hand.

Association of polymorphisms rs1800012 in COL1A1 with sports-related tendon and ligament injuries: a meta-analysis

PubMed Central

Wang, Chunguang; Li, Hao; Chen, Kang; Wu, Bing; Liu, Haifeng

2017-01-01

It has been reported that the single nucleotide polymorphism (SNP) rs1800012 in COL1A1 might be associated with the susceptibility to sports-related tendon and ligament injuries such as ACL injuries, Achilles tendon injuries, shoulder dislocations and tennis elbow. But the data from different studies have been conflicting. Here we attempted to systematically summarize and clarify the association between the SNP and sports-related tendon and ligament injuries risk. Six eligible studies including 933 cases and 1,381 controls were acquired from PubMed, Web Of Science and Cochrane library databases. Significant association was identified in homozygote model (TT versus GG: OR=0.17, 95%CI 0.08-0.35, PH=0.00) and recessive model (TT versus GT/GG: OR=0.21, 95%CI 0.10-0.44, PH=0.00). Our results indicated that COL1A1 rs1800012 polymorphism may be associated with the reduced risk of sports-related tendon or ligament injuries, especially in ACL injuries, and that rare TT may played as a protective role. PMID:28206959

The effectiveness of wrist guards for reducing wrist and elbow accelerations resulting from simulated forward falls.

PubMed

Burkhart, Timothy A; Andrews, David M

2010-08-01

The effectiveness of wrist guards and modifying elbow posture for reducing impact-induced accelerations at the wrist and elbow, for the purpose of decreasing upper extremity injury risk during forward fall arrest, has not yet been documented in living people. A seated human pendulum was used to simulate the impact conditions consistent with landing on outstretched arms during a forward fall. Accelerometers measured the wrist and elbow response characteristics of 28 subjects following impacts with and without a wrist guard, and with elbows straight or slightly bent. Overall, the wrist guard was very effective, with significant reductions in peak accelerations at the elbow in the axial and off-axis directions, and in the off-axis direction at the wrist by almost 50%. The effect of elbow posture as an intervention strategy was mixed; a change in magnitude and direction of the acceleration response was documented at the elbow, while there was little effect at the wrist. Unique evidence was presented in support of wrist guard use in activities like in-line skating where impacts to the hands are common. The elbow response clearly shows that more proximal anatomical structures also need to be monitored when assessing the effectiveness of injury prevention strategies.

Long-latency reflexes of elbow and shoulder muscles suggest reciprocal excitation of flexors, reciprocal excitation of extensors, and reciprocal inhibition between flexors and extensors

PubMed Central

Meriggi, Jenna; Parikh, Nidhi; Saad, Kenneth

2016-01-01

Postural corrections of the upper limb are required in tasks ranging from handling an umbrella in the changing wind to securing a wriggling baby. One complication in this process is the mechanical interaction between the different segments of the arm where torque applied at one joint induces motion at multiple joints. Previous studies have shown the long-latency reflexes of shoulder muscles (50–100 ms after a limb perturbation) account for these mechanical interactions by integrating information about motion of both the shoulder and elbow. It is less clear whether long-latency reflexes of elbow muscles exhibit a similar capability and what is the relation between the responses of shoulder and elbow muscles. The present study utilized joint-based loads tailored to the subjects' arm dynamics to induce well-controlled displacements of their shoulder and elbow. Our results demonstrate that the long-latency reflexes of shoulder and elbow muscles integrate motion from both joints: the shoulder and elbow flexors respond to extension at both joints, whereas the shoulder and elbow extensors respond to flexion at both joints. This general pattern accounts for the inherent flexion-extension coupling of the two joints arising from the arm's intersegmental dynamics and is consistent with spindle-based reciprocal excitation of shoulder and elbow flexors, reciprocal excitation of shoulder and elbow extensors, and across-joint inhibition between the flexors and extensors. PMID:26864766

Movement-related and steady-state electromyographic activity of human elbow flexors in slow transition movements between two equilibrium states.

PubMed

Tal'nov, A N; Cherkassky, V L; Kostyukov, A I

1997-08-01

The electromyograms were recorded in healthy human subjects by surface electrodes from the mm. biceps brachii (caput longum et. brevis), brachioradialis, and triceps brachii (caput longum) during slow transition movements in elbow joint against a weak extending torque. The test movements (flexion transitions between two steady-states) were fulfilled under visual control through combining on a monitor screen a signal from a joint angle sensor with a corresponding command generated by a computer. Movement velocities ranged between 5 and 80 degrees/s, subjects were asked to move forearm without activation of elbow extensors. Surface electromyograms were full-wave rectified, filtered and averaged within sets of 10 identical tests. Amplitudes of dynamic and steady-state components of the electromyograms were determined in dependence on a final value of joint angle, slow and fast movements were compared. An exponential-like increase of dynamic component was observed in electromyograms recorded from m. biceps brachii, the component had been increased with movement velocity and with load increment. In many experiments a statistically significant decrease of static component could be noticed within middle range of joint angles (40-60 degrees) followed by a well expressed increment for larger movements. This pattern of the static component in electromyograms could vary in different experiments even in the same subjects. A steady discharge in m. brachioradialis at ramp phase has usually been recorded only under a notable load. Variable and quite often unpredictable character of the static components of the electromyograms recorded from elbow flexors in the transition movements makes it difficult to use the equilibrium point hypothesis to describe the central processes of movement. It has been assumed that during active muscle shortening the dynamic components in arriving efferent activity should play a predominant role. A simple scheme could be proposed for transition to a steady-state after shortening. Decrease of the efferent inflow can evoke internal lengthening of the contractile elements in muscle and, as a result, hysteresis increase in the muscle contraction efficiency. Effectiveness in maintenance of the steady position seems to also be enhanced due to muscle thixotropy and friction processes in the joint. Hysteresis after-effects in elbow flexors were demonstrated as a difference in steady-state levels of electromyograms with oppositely directed approaches to the same joint position.

The role of arthroscopy in chronic elbow instability.

PubMed

Goodwin, David; Dynin, Maria; Macdonnell, J Ryan; Kessler, Michael W

2013-12-01

Elbow arthroscopy has had an emerging role in the management of many disorders of the elbow. In patients with chronic elbow instability, several arthroscopic techniques have been described in the diagnosis and management of posterolateral rotatory instability and valgus instability. We performed a systematic review investigating the role of arthroscopy in posterolateral rotatory instability and valgus instability in the elbow using the PubMed and CINAHL (Cumulative Index to Nursing and Allied Health Literature) databases, and the Cochrane Database of Systematic Reviews, consisting of articles from peer-reviewed journals published in the English language after January 1, 1991. Search criteria initially identified 249 articles. Twenty-five articles met criteria for inclusion. This included 17 review articles, 4 cadaveric studies, 3 retrospective studies, and 1 prospective study. Two of the retrospective studies compared arthroscopic and open techniques. Articles included in this systematic review concluded that arthroscopy is an accurate adjunct to physical examination and imaging in the diagnosis of chronic elbow instability and affords an exceptional view of the joint with the ability to address intra-articular pathologic conditions. Arthroscopic surgical techniques have shown equivalent clinical outcomes in a comparison of arthroscopic and open techniques. Elbow arthroscopy is a valuable tool in the diagnosis and management of chronic elbow instability. Patients treated arthroscopically benefit from additional diagnostic techniques, improved visualization of the elbow joint, the ability to address coexisting intra-articular pathologic conditions, and minimal soft tissue injury with no clinical consequences in outcomes. With such significant advantages, the use of elbow arthroscopy is likely to expand in the management of chronic elbow instability. Level IV, systematic review. Copyright © 2013 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Total elbow arthroplasty for primary osteoarthritis.

PubMed

Schoch, Bradley S; Werthel, Jean-David; Sánchez-Sotelo, Joaquín; Morrey, Bernard F; Morrey, Mark

2017-08-01

Primary osteoarthritis of the elbow is a less common indication for total elbow arthroplasty (TEA). Higher complication rates in younger, active patients may offset short-term improvements in pain and function. The purpose of this study was to determine pain relief, functional outcomes, complications, and survival of TEA in this population. Between 1984 and 2011, 20 consecutive TEAs were performed for primary elbow osteoarthritis. Two patients died before the 2-year follow-up. Mean age at surgery was 68 years (range, 51-85 years). Outcome measures included pain, motion, Mayo Elbow Performance Score, satisfaction, complications, and reoperations. Mean follow-up was 8.9 years (range, 2-20 years). Three elbows sustained mechanical failures. Complications included intraoperative fracture (n = 2), wound irrigation and débridement (n = 1), bony ankylosis (n = 1), humeral loosening (n = 1), humeral component fracture (n = 1), and mechanical failure of a radial head component (n = 1). Fifteen elbows without mechanical failure were examined clinically. Pain improved from 3.6 to 1.5 (P < .001). Range of motion remained clinically unchanged (P > .05), with preoperative flexion contractures not improving. Mayo Elbow Performance Scores were available for 13 elbows without mechanical failure, averaging 81.5 points (range, 60-100 points); these were graded as excellent (n = 5), good (n = 2), and fair (n = 6). Subjectively, all patients without mechanical failure were satisfied. TEA represents a reliable surgical option for pain relief in patients with primary osteoarthritis. However, restoration of extension is not always obtained, indicating that more aggressive soft tissue releases or bony resection should be considered. Complications occurred in a large number of elbows, but mechanical failure was low considering the nature of this population and the length of follow-up. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Elbow reconstruction with a pedicled thoracodorsal artery perforator flap after excision of an upper-extremity giant hairy nevus.

PubMed

Oksüz, Sinan; Ulkür, Ersin; Tuncer, Serhan; Sever, Celalettin; Karagöz, Hüseyin

2013-04-01

The complexity of managing large soft-tissue defects at the elbow region by conventional techniques arises from the difficulty of providing sufficient tissue with adequate elasticity and durability. Reconstruction options that allow early mobilisation and avoid the risk of functional loss should be considered to achieve defect closure at the elbow region. A 21-year-old man presented with a congenital giant hairy nevus on his left upper extremity. The nevus was excised and the resulting raw surface after the excision was covered with a split-thickness skin graft except for the elbow region. The elbow was covered in one stage with an ipsilateral 24 cm long pedicled thoracodorsal artery perforator (TDAP) flap. The follow-up examination 3 years after total reconstruction demonstrated durable elbow support provided by the TDAP flap. The patient revealed no complaint considering pain or sensitivity even when exposed to mechanical stress. Split-thickness skin grafting of the large superficial defects is almost always possible; however, impairment of the function on joint areas due to gradual contraction and skin graft propensity to ulcers under mechanical stresses can be devastating. The elbow is a weight-bearing area of the body. Elbow defects require durable and thin soft-tissue coverage and the tissue cover must possess excellent elastic properties to re-establish elbow mobility. The TDAP flap is an ideal choice for elbow soft-tissue defects. The longest pedicle length reported for the TDAP flap is 23 cm. In our case, the pedicle length was 24 cm and it was possible to transfer this flap to the elbow on its pedicle. A pedicled TDAP skin flap so as to provide elbow coverage in one stage is a useful choice to retain in one's armamentarium. Copyright © 2012 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Arthroscopic Debridement for Primary Degenerative Osteoarthritis of the Elbow Leads to Significant Improvement in Range of Motion and Clinical Outcomes: A Systematic Review.

PubMed

Sochacki, Kyle R; Jack, Robert A; Hirase, Takashi; McCulloch, Patrick C; Lintner, David M; Liberman, Shari R; Harris, Joshua D

2017-12-01

The purpose of this investigation was to determine whether arthroscopic debridement of primary elbow osteoarthritis results in statistically significant and clinically relevant improvement in (1) elbow range of motion and (2) clinical outcomes with (3) low complication and reoperation rates. A systematic review was registered with PROSPERO and performed using PRISMA guidelines. Databases were searched for studies that investigated the outcomes of arthroscopic debridement for the treatment of primary osteoarthritis of the elbow in adult human patients. Study methodological quality was analyzed. Studies that included post-traumatic arthritis were excluded. Elbow motion and all elbow-specific patient-reported outcome scores were eligible for analysis. Comparisons between preoperative and postoperative values from each study were made using 2-sample Z-tests (http://in-silico.net/tools/statistics/ztest) using a P value < .05. Nine articles (209 subjects, 213 elbows, 187 males, 22 females, mean age 45.7 ± 7.1 years, mean follow-up 41.7 ± 16.3. months; 75% right, 25% left; 79% dominant elbow, 21% nondominant) were analyzed. Elbow extension (23.4°-10.7°, Δ 12.7°), flexion (115.9°-128.7°, Δ 12.8°), and global arc of motion (94.5°-117.6°, Δ 23.1°) had statistically significant and clinically relevant improvement following arthroscopic debridement (P < .0001 for all). There was also a statistically significant (P < .0001) and clinically relevant improvement in the Mayo Elbow Performance Score (60.7-84.6, Δ 23.9) postoperatively. Six patients (2.8%) had postoperative complications. Nine (4.2%) underwent reoperation. Elbow arthroscopic debridement for primary degenerative osteoarthritis results in statistically significant and clinically relevant improvement in elbow range of motion and clinical outcomes with low complication and reoperation rates. Systematic review of level IV studies. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Design of a Soft Robotic Elbow Sleeve with Passive and Intent-Controlled Actuation

PubMed Central

Koh, Tze Hui; Cheng, Nicholas; Yap, Hong Kai; Yeow, Chen-Hua

2017-01-01

The provision of continuous passive, and intent-based assisted movements for neuromuscular training can be incorporated into a robotic elbow sleeve. The objective of this study is to propose the design and test the functionality of a soft robotic elbow sleeve in assisting flexion and extension of the elbow, both passively and using intent-based motion reinforcement. First, the elbow sleeve was developed, using elastomeric and fabric-based pneumatic actuators, which are soft and lightweight, in order to address issues of non-portability and poor alignment with joints that conventional robotic rehabilitation devices are faced with. Second, the control system was developed to allow for: (i) continuous passive actuation, in which the actuators will be activated in cycles, alternating between flexion and extension; and (ii) an intent-based actuation, in which user intent is detected by surface electromyography (sEMG) sensors attached to the biceps and triceps, and passed through a logic sequence to allow for flexion or extension of the elbow. Using this setup, the elbow sleeve was tested on six healthy subjects to assess the functionality of the device, in terms of the range of motion afforded by the device while in the continuous passive actuation. The results showed that the elbow sleeve is capable of achieving approximately 50% of the full range of motion of the elbow joint among all subjects. Next, further experiments were conducted to test the efficacy of the intent-based actuation on these healthy subjects. The results showed that all subjects were capable of achieving electromyography (EMG) control of the elbow sleeve. These preliminary results show that the elbow sleeve is capable of carrying out continuous passive and intent-based assisted movements. Further investigation of the clinical implementation of the elbow sleeve for the neuromuscular training of neurologically-impaired persons, such as stroke survivors, is needed. PMID:29118693

Physical Risk Factors for a Medial Elbow Injury in Junior Baseball Players: A Prospective Cohort Study of 353 Players.

PubMed

Sakata, Jun; Nakamura, Emi; Suzukawa, Makoto; Akaike, Atsushi; Shimizu, Kuniaki

2017-01-01

The physical risk factors for a medial elbow injury in junior baseball players are unknown. To identify the risk factors for an initial medial elbow injury in junior baseball players. Case-control study; Level of evidence, 3. Junior baseball players (aged 6-12 years) without a history of elbow pain underwent a clinical assessment, ultrasonography, and physical function measurements before the baseball season started. Bilateral passive range of motion (ROM) of elbow extension and flexion, external rotation (ER) and internal rotation (IR) of the shoulder, and ER and IR of the hip were measured. IR and ER strength of the shoulder and scapular muscles were measured on both sides. The thoracic kyphosis angle was measured with participants in a relaxed standing position. Before these examinations, every participant completed a questionnaire regarding his or her age, sex, total years of baseball played, position in baseball, number of balls thrown, and episodes of pain during throwing. After the initial test session, each participant was followed up for 12 months to assess for the occurrence of a new injury. Multiple regression analysis was used to identify the risk factors for a medial elbow injury. Seventy-eight players (22.1%) sustained a medial elbow injury. Age ≥9 years (odds ratio [OR], 2.708; 95% CI, 1.224-5.990), pitcher position (OR, 2.620; 95% CI, 1.389-4.941), >100 throws per day (OR, 1.936; 95% CI, 1.072-3.497), thoracic kyphosis angle ≥30° (OR, 2.501; 95% CI, 1.381-4.531), and elbow extension deficit ≥5° (OR, 1.973; 95% CI, 1.022-3.809) were significantly associated with a medial elbow injury. The incidence of an initial medial elbow injury was 22.1%. Age, number of throws per day, thoracic kyphosis angle, and elbow extension deficit are newly discovered risk factors related to physical function. Improvement of the posture and early detection of a silent elbow extension deficit may prevent a medial elbow injury.

Revisiting the anatomy and biomechanics of the anconeus muscle and its role in elbow stability.

PubMed

Pereira, Barry P

2013-07-01

Recent studies have designated the anconeus muscle as an option for use as a pedicled flap for covering soft tissue defects about the elbow, with reported minimal risk of morbidity. This has raised the question as to the importance of the anconeus muscle and as to whether this is truly an accessory muscle that can be sacrificed, or whether the anconeus muscle significantly contributes to elbow and forearm stability? This study revisits the anatomy and biomechanics of the anconeus muscle and aims to investigate the neuromuscular compartments of the anconeus muscle and to determine the changes in the muscle length, fibre length and moment arm over a range of elbow flexion angles for each compartment. An anatomical study on 8 human cadavers (51-77 years of age) was done and a 2-dimensional kinematic elbow model developed to determine changes in the muscle length and moment arm of the muscle related to changes in elbow flexion angles. The muscle was modelled with two possible lines of action, one along the posterior and another on the anterior edge of the muscle as they had different muscle fibre lengths (posterior: average of 32 mm, anterior: average of 20 mm). The anterior edge also had an aponeurosis which was 70% of its length. From 0 to 120° elbow flexion, the length of the posterior and anterior edges increased with a maximum change recorded at 90° elbow flexion (31.7±1.0 mm and 65.3±1.4 mm, respectively). The moment arm is 14-mm at 0° flexion, but between the posterior and anterior edges it decreases at different rates with increasing elbow flexion angle. Beyond 80°, the anterior edge behaves as an elbow flexor, while the posterior edge remains an elbow extensor. The study demonstrates that the anconeus muscle has two neuromuscular compartments each with distinct intramuscular innervations and muscle fibre lengths. The posterior and deep aspect of the muscle functions as an elbow extensor decreasing in influence with increasing elbow flexion angle. The anterior superficial aspect which is adjacent and parallel to the lateral collateral ligaments, would most likely work in unison to provide constraint to the posterolateral stability of the elbow. Copyright © 2012. Published by Elsevier GmbH.

Heritabilities and genetic trends for elbow score as recorded by the New Zealand Veterinary Association Elbow Dysplasia Scheme (1992-2013) in four breeds of dog.

PubMed

Soo, M; Lopez-Villalobos, N; Worth, A J

2018-05-01

To estimate the heritability of the New Zealand Veterinary Association (NZVA) elbow phenotype, obtain estimated breeding values (EBV) for the worst-elbow score and estimate the genetic trends for this trait in four populous breeds of dogs, using the records from the NZVA Canine Elbow Dysplasia Scheme database (1992-2013). Overall, 4,070 elbow records from a pedigree of 11,311 dogs were available for animals scored between 1992 and 2013. The worst elbow score between the left and right elbows was identified for each dog and used for EBV analysis. Estimates of heritability and EBV for the elbow score of dogs from German Shepherd dog, Labrador Retriever, Golden Retriever and Rottweiler breeds were obtained using restricted maximum likelihood procedures with a within-breed linear animal model. The model included the fixed effects of sex and birth year, with age at scoring as a covariable, and the random effect of animal. Genetic trends for the worst-elbow score were calculated as the regression coefficient of the EBV, weighted by reliabilities, on year of birth. The estimates of heritability for worst-elbow score were 0.25 (SE 0.06) in German Shepherd dogs, 0.46 (SE 0.06) in Labrador Retrievers, 0.18 (SE 0.07) in Golden Retrievers and 0.29 (SE 0.11) in Rottweilers. The genetic trend for German Shepherd dogs was -0.0082 (SE 0.0015), for Labrador Retrievers was -0.0016 (SE 0.0016), for Golden Retrievers was -0.0033 (SE 0.0010) and for Rottweilers was -0.0070 (SE 0.0023) units per annum, which were different from zero (p<0.01) in all breeds except Labrador Retrievers. A small but favourable response to selection was achieved by three of the four breeds in the study period; during which selection for elbow traits has been largely voluntary. While the magnitude of genetic change in terms of elbow units per annum may appear small, it must be remembered that elbow scoring grades only range from 0-3. Greater improvement may be possible if compulsory screening was a requirement for pedigree breeding stock, and if greater selection pressure were applied on the basis on an individual's EBV, rather than the worst-elbow score alone. The maintenance of an open registry, with transparency of EBV information made available to all breeders, may enhance selection intensity opportunities and potentially assist with the process and progress of breeding selection.

Revision allograft reconstruction of the lateral collateral ligament complex in elbows with previous failed reconstruction and persistent posterolateral rotatory instability.

PubMed

Baghdadi, Yaser M K; Morrey, Bernard F; O'Driscoll, Shawn W; Steinmann, Scott P; Sanchez-Sotelo, Joaquin

2014-07-01

Primary reconstruction of the lateral collateral ligament complex (LCLC) using graft tissue restores elbow stability in many, but not all, elbows with acute or chronic posterolateral rotatory instability (PLRI). Revision reconstruction using a tendon allograft is occasionally considered for persistent PLRI, but the outcome of revision ligament reconstruction in this setting is largely unknown. We determined whether revision allograft ligament reconstruction can (1) restore the stability and (2) result in improved elbow scores for patients with persistent PLRI of the elbow after a previous failed primary reconstructive attempt and in the context of the diverse pathology being addressed. Between 2001 and 2011, 160 surgical elbow procedures were performed at our institution for the LCLC reconstruction using allograft tissue. Only patients undergoing revision allograft reconstruction of the LCLC for persistent PLRI with a previous failed primary reconstructive attempt using graft tissue and at least I year of followup were included in the study. Eleven patients (11 elbows) fulfilled our inclusion criteria and formed our study cohort. The cohort consisted of six female patients and five male patients. The mean age at the time of revision surgery was 36 years (range, 14-59 years). The revision allograft reconstruction was carried out after a mean of 3 years (range, 2.5 months to 9 years) from a failed attempted reconstruction of the LCLC. Osseous deficiency to some extent was identified in the preoperative radiographs of eight elbows. Mean followup was 5 years (range, 1-12 years). Revision allograft reconstruction of the LCLC restored elbow stability in eight of the 11 elbows; two of the three elbows with persistent instability were operated on a third time (at 6 and 7 months after allograft revision reconstruction). For elbows with no persistent instability, the mean Mayo Elbow Performance Score at most recent followup was 83 points (range, 60-100 points), and six elbows were rated with a good or excellent result. All patients with persistent instability had some degree of preoperative bone loss. Revision allograft reconstruction of the LCLC is an option for treating recurrent PLRI, although this is a complex and resistant problem, and nearly ½ of the patients in this cohort either had persistent instability and/or had a fair or poor elbow score. Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

MRI and arthroscopy correlations of the elbow: a case-based approach.

PubMed

Abrams, Geoffrey D; Stoller, David W; Safran, Marc R

2012-01-01

The number of elbow arthroscopies and indications for the procedure have increased significantly since the advent of modern elbow arthroscopy in the 1980s. In addition to the patient history, physical examination, and plain radiography, MRI is an important tool for the clinician in diagnosing several pathologies within and around the elbow. Understanding the pathophysiology and clinical presentation and being familiar with the MRI characteristics of a variety of elbow conditions will assist the physician in making an accurate diagnosis and help guide appropriate treatment.

Elbow injuries at the London 2012 Summer Olympic Games: demographics and pictorial imaging review.

PubMed

Bethapudi, Sarath; Robinson, Philip; Engebretsen, Lars; Budgett, Richard; Vanhegan, Ivor S; O'Connor, Philip

2013-09-01

Elbow injuries in Olympic sports and their imaging findings have not been described previously. The main objective of this article is to analyze the demographic data on imaging of elbow injuries at the London 2012 Summer Olympic Games and to review the spectrum of imaging findings. Elbow injuries were seen in a wide variety of sports. Judo and weight-lifting contributed nearly half of all injuries, with only a surprisingly small number of injuries seen in throwing athletes. Knowledge of elbow anatomy coupled with awareness of types of elbow injuries and their prevalence in various sports will contribute toward improving diagnostic accuracy, handling of workload, and overall provision of services at similar major international sporting events in the future.

Ultrasonographic Differentiation of Lateral Elbow Pain

PubMed Central

Obuchowicz, R.; Bonczar, M.

2016-01-01

Lateral elbow pain is often attributed to degenerative or posttraumatic impairment of the common extensor tendon. Ultrasonography assesses the soft tissue structures of the lateral elbow, allowing the differentiation between various underlying processes, including angiofibroblastic degeneration, hyaline degeneration, and inflammation, and exclusion of other possible causes of pain such as posterior interosseous and lateral antebrachial nerve compression. Furthermore, the real-time imaging nature of ultrasonography enables the detection of impingement of the lateral synovial fold, degenerative changes in the elbow recess, and elbow posterolateral instability during dynamic maneuvers. Ultrasonography is widely accessible and well tolerated by patients, making it a perfect method for establishing an initial diagnosis and monitoring the healing process. This review describes the possible causes of lateral elbow pain and their ultrasonographic differentiation. PMID:27689169

Anterior cervical distraction and screw elevating–pulling reduction for traumatic cervical spine fractures and dislocations

PubMed Central

Li, Haoxi; Yong, Zhiyao; Chen, Zhaoxiong; Huang, Yufeng; Lin, Zhoudan; Wu, Desheng

2017-01-01

Abstract Treatment of cervical fracture and dislocation by improving the anterior cervical technique. Anterior cervical approach has been extensively used in treating cervical spine fractures and dislocations. However, when this approach is used in the treatment of locked facet joints, an unsatisfactory intraoperative reduction and prying reduction increases the risk of secondary spinal cord injury. Thus, herein, the cervical anterior approach was improved. With distractor and screw elevation therapy during surgery, the restoration rate is increased, and secondary injury to the spinal cord is avoided. To discuss the feasibility of the surgical method of treating traumatic cervical spine fractures and dislocations and the clinical application. This retrospective study included the duration of patients’ hospitalization from January 2005 to June 2015. The potential risks of surgery (including death and other surgical complications) were explained clearly, and written consents were obtained from all patients before surgery. The study was conducted on 86 patients (54 males and 32 females, average age of 40.1 ± 5.6 years) with traumatic cervical spine fractures and dislocations, who underwent one-stage anterior approach treatment. The effective methods were evaluated by postoperative follow-up. The healing of the surgical incision was monitored in 86 patients. The follow-up duration was 18 to 36 (average 26.4 ± 7.1) months. The patients achieved bones grafted fusion and restored spine stability in 3 to 9 (average 6) months after the surgery. Statistically, significant improvement was observed by Frankel score, visual analog scale score, Japanese Orthopedic Association score, and correction rate of the cervical spine dislocation pre- and postoperative (P < .01). The modified anterior cervical approach is simple with a low risk but a good effect in reduction. In addition, it can reduce the risk of iatrogenic secondary spinal cord injury and maintain optimal cervical spine stability as observed during follow-ups. Therefore, it is suitable for clinical promotion and application. PMID:28658125

Nanostructural engineering of nitride nucleation layers for GaN substrate dislocation reduction.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koleske, Daniel David; Lee, Stephen Roger; Lemp, Thomas Kerr

2009-07-01

With no lattice matched substrate available, sapphire continues as the substrate of choice for GaN growth, because of its reasonable cost and the extensive prior experience using it as a substrate for GaN. Surprisingly, the high dislocation density does not appear to limit UV and blue LED light intensity. However, dislocations may limit green LED light intensity and LED lifetime, especially as LEDs are pushed to higher current density for high end solid state lighting sources. To improve the performance for these higher current density LEDs, simple growth-enabled reductions in dislocation density would be highly prized. GaN nucleation layers (NLs)more » are not commonly thought of as an application of nano-structural engineering; yet, these layers evolve during the growth process to produce self-assembled, nanometer-scale structures. Continued growth on these nuclei ultimately leads to a fully coalesced film, and we show in this research program that their initial density is correlated to the GaN dislocation density. In this 18 month program, we developed MOCVD growth methods to reduce GaN dislocation densities on sapphire from 5 x 10{sup 8} cm{sup -2} using our standard delay recovery growth technique to 1 x 10{sup 8} cm{sup -2} using an ultra-low nucleation density technique. For this research, we firmly established a correlation between the GaN nucleation thickness, the resulting nucleation density after annealing, and dislocation density of full GaN films grown on these nucleation layers. We developed methods to reduce the nuclei density while still maintaining the ability to fully coalesce the GaN films. Ways were sought to improve the GaN nuclei orientation by improving the sapphire surface smoothness by annealing prior to the NL growth. Methods to eliminate the formation of additional nuclei once the majority of GaN nuclei were developed using a silicon nitride treatment prior to the deposition of the nucleation layer. Nucleation layer thickness was determined using optical reflectance and the nucleation density was determined using atomic force microscopy (AFM) and Nomarski microscopy. Dislocation density was measured using X-ray diffraction and AFM after coating the surface with silicon nitride to delineate all dislocation types. The program milestone of producing GaN films with dislocation densities of 1 x 10{sup 8} cm{sup -2} was met by silicon nitride treatment of annealed sapphire followed by the multiple deposition of a low density of GaN nuclei followed by high temperature GaN growth. Details of this growth process and the underlying science are presented in this final report along with problems encountered in this research and recommendations for future work.« less

Isometric elbow extensors strength in supine- and prone-lying positions.

PubMed

Abdelzaher, Ibrahim E; Ababneh, Anas F; Alzyoud, Jehad M

2013-01-01

The purpose of this study was to compare isometric strength of elbow extensors measured in supine- and prone-lying positions at elbow flexion angles of 45 and 90 degrees. Twenty-two male subjects under single-blind procedures participated in the study. Each subject participated in both supine-lying and prone-lying measuring protocols. Calibrated cable tensiometer was used to measure isometric strength of the right elbow extensors and a biofeedback electromyography was used to assure no substitution movements from shoulder girdle muscles. The mean values of isometric strength of elbow extensors measured from supine-lying position at elbow flexion angles of 45 and 90 degrees were 11.1  ±  4.2 kg and 13.1  ±  4.6 kg, while those measured from prone-lying position were 9.9  ±  3.6 kg and 12  ±  4.2 kg, respectively. There is statistical significant difference between the isometric strength of elbow extensors measured from supine-lying position at elbow flexion angles of 45 and 90 degrees compared to that measured from prone-lying position (p  <  0.05). The results suggest that in manual muscle testing starting position can affect the isometric strength of elbow extensors since supine-lying starting position is better than prone-lying starting position.

Effect of Anconeus Muscle Blocking on Elbow Kinematics: Electromyographic, Inertial Sensors and Finite Element Study.

PubMed

Miguel-Andres, Israel; Alonso-Rasgado, Teresa; Walmsley, Alan; Watts, Adam C

2017-03-01

The specific contribution of the anconeus muscle to elbow function is still uncertain. This study aimed to investigate the effect on elbow kinematics and kinetics of blocking anconeus using lidocaine. Ten healthy volunteers performed experimental trials involving flexion-extension and supination-pronation movements in horizontal and sagittal planes. Inertial sensors and surface electromyography were used to record elbow kinematics and kinetics and electrical activity from the anconeus, biceps and triceps brachii before and after blocking anconeus. Moreover, a finite element model of the elbow was created to further investigate the contribution of anconeus to elbow kinematics. The electrical activity results from the trials before blocking clearly indicated that activity of anconeus was increased during extension, suggesting that it behaves as an extensor. However, blocking anconeus had no effect on the elbow kinematics and kinetics, including the angular velocity, net torque and power of the joint. The electrical activity of the biceps and triceps brachii did not alter significantly following anconeus blocking. These results suggest that anconeus is a weak extensor, and the relative small contribution of anconeus to extension before blocking was compensated by triceps brachii. The finite element results indicated that anconeus does not contribute significantly to elbow kinematics.

Linking of total elbow prosthesis during surgery; a biomechanical analysis.

PubMed

De Vos, Maarten J; Wagener, Marc L; Hendriks, Jan C M; Eygendaal, Denise; Verdonschot, Nico

2013-09-01

Presently, 2 types of elbow prostheses are used: unlinked and linked. The Latitude total elbow prosthesis allows the surgeon to decide during the implantation whether the prosthesis is placed unlinked or linked, and whether the native radial head is retained, resected, or replaced. The purpose of this study is to assess and to compare the varus and valgus laxity of the unlinked and linked version of the latitude total elbow prosthesis with: (1) the native radial head preserved, (2) the native radial head excised, and (3) the native radial head replaced by a radial head component. Biomechanical testing was performed on 14 fresh-frozen upper limb specimens. Linking the prosthesis predominantly influences the valgus laxity of the elbow. Linking the Latitude total elbow prosthesis results in increased valgus stability. In the linked version of the total elbow prosthesis, the radial head only plays a small part in both valgus and varus stability. An unlinked situation is not advised in absence of a native radial head or in case of inability to replace the radial head. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Phase-dependence of elbow muscle coactivation in front crawl swimming.

PubMed

Lauer, Jessy; Figueiredo, Pedro; Vilas-Boas, João Paulo; Fernandes, Ricardo J; Rouard, Annie Hélène

2013-08-01

Propulsion in swimming is achieved by complex sculling movements with elbow quasi-fixed on the antero-posterior axis to transmit forces from the hand and the forearm to the body. The purpose of this study was to investigate how elbow muscle coactivation was influenced by the front crawl stroke phases. Ten international level male swimmers performed a 200-m front crawl race-pace bout. Sagittal views were digitized frame by frame to determine the stroke phases (aquatic elbow flexion and extension, aerial elbow flexion and extension). Surface electromyograms (EMG) of the right biceps brachii and triceps brachii were recorded and processed using the integrated EMG to calculate a coactivation index (CI) for each phase. A significant effect of the phases on the CI was revealed with highest levels of coactivation during the aquatic elbow flexion and the aerial elbow extension. Swimmers stabilize the elbow joint to overcome drag during the aquatic phase, and act as a brake at the end of the recovery to replace the arm for the next stroke. The CI can provide insight into the magnitude of mechanical constraints supported by a given joint, in particular during a complex movement. Copyright © 2013 Elsevier Ltd. All rights reserved.

Golfer's Elbow

MedlinePlus

... your elbow can cause golfer's elbow. This includes painting, raking, hammering, chopping wood, using a computer, doing ... using older golfing irons, consider upgrading to lighter graphite clubs. If you play tennis, a racket with ...

A systematic, multimodality approach to emergency elbow imaging.

PubMed

Singer, Adam D; Hanna, Tarek; Jose, Jean; Datir, Abhijit

2016-01-01

The elbow is a complex synovial hinge joint that is frequently involved in both athletic and nonathletic injuries. A thorough understanding of the normal anatomy and various injury patterns is essential when utilizing diagnostic imaging to identify damaged structures and to assist in surgical planning. In this review, the elbow anatomy will be scrutinized in a systematic approach. This will be followed by a comprehensive presentation of elbow injuries that are commonly seen in the emergency department accompanied by multimodality imaging findings. A short discussion regarding pitfalls in elbow imaging is also included. Copyright © 2015 Elsevier Inc. All rights reserved.

Tennis elbow surgery

MedlinePlus

Lateral epicondylitis - surgery; Lateral tendinosis - surgery; Lateral tennis elbow - surgery ... Surgery to repair tennis elbow is often an outpatient surgery. This means you will not stay in the hospital overnight. You will be given ...

The Relationship of Throwing Arm Mechanics and Elbow Varus Torque: Within-Subject Variation for Professional Baseball Pitchers Across 82,000 Throws.

PubMed

Camp, Christopher L; Tubbs, Travis G; Fleisig, Glenn S; Dines, Joshua S; Dines, David M; Altchek, David W; Dowling, Brittany

2017-11-01

Likely due to the high level of strain exerted across the elbow during the throwing motion, elbow injuries are on the rise in baseball. To identify at-risk athletes and guide postinjury return-to-throw programs, a better understanding of the variables that influence elbow varus torque is desired. To describe the within-subject relationship between elbow varus torque and arm slot and arm rotation in professional baseball pitchers. Descriptive laboratory study. A total of 81 professional pitchers performed 82,000 throws while wearing a motusBASEBALL sensor and sleeve. These throws represented a combination of throw types, such as warm-up/catch, structured long-toss, bullpen throwing from a mound, and live game activity. Variables recorded for each throw included arm slot (angle of the forearm relative to the ground at ball release), arm speed (maximal rotational velocity of the forearm), arm rotation (maximal external rotation of the throwing arm relative to the ground), and elbow varus torque. Linear mixed-effects models and likelihood ratio tests were used to estimate the relationship between elbow varus torque and arm slot, arm speed, and arm rotation within individual pitchers. All 3 metrics-arm slot (χ 2 = 428, P < .001), arm speed (χ 2 = 57,683, P < .001), and arm rotation (χ 2 = 1392, P < .001)-were found to have a significant relationship with elbow varus torque. Within individual athletes, a 1-N.m increase in elbow varus torque was associated with a 13° decrease in arm slot, a 116 deg/s increase in arm speed, and an 8° increase in arm rotation. Elbow varus torque increased significantly as pitchers increased their arm rotation during the arm cocking phase, increased the rotational velocity of their arm during the arm acceleration phase of throwing, and decreased arm slot at ball release. Thus, shoulder flexibility, arm speed, and elbow varus torque (and likely injury risk) are interrelated and should be considered collectively when treating pitchers. It is well established that elbow varus torque is related to ulnar collateral ligament injuries in overhead throwers. This study describes the relationship of arm slot, arm speed, and arm rotation to elbow varus torque in an attempt to identify modifiable risk factors for injury.

A review of epidemiology of paediatric elbow injuries in sports.

PubMed

Magra, Merzesh; Caine, Dennis; Maffulli, Nicola

2007-01-01

The elbow is a common site of orthopaedic injury in the paediatric population. The number of these injuries continues to rise following increased levels of participation in paediatric recreational and competitive sport. Injuries to the paediatric elbow can be classified as either overuse or acute. Delineating injury patterns to the elbow in children can be challenging, given the cartilaginous composition of the distal humerus and the multiple secondary ossification centres that appear and unite with the epiphysis at defined ages. Pitching in baseball, serving in tennis, spiking in volleyball, passing in American football and launching in javelin-throwing can all produce elbow pathology by forceful valgus stress, with medial stretching, lateral compression and posterior impingement. In children and adolescents, the epiphyseal plate is weaker than the surrounding ligaments, predisposing them to epiphyseal plate injuries. On the other hand, post-pubescent or skeletally mature athletes are more prone to tendinous or ligamentous injury. Injuries may cause significant impact on the athlete, parents and healthcare system. With the exception of baseball, there are few prospective cohort studies on the epidemiological trends of childhood elbow injuries in other sports. This paper aims to describe the epidemiological trends in paediatric elbow injuries related to sports, suggests prevention strategies and discusses the scope for further research. A web-based search of existing articles pertaining to paediatric elbow injuries in sports was performed. The implications of acute and overuse injuries and the possibility of permanent damage should be understood by parents, coaches and the athletes. Proper understanding of the intrinsic and extrinsic risk factors that could lead to elbow injuries is thus required. Measures to prevent elbow injuries should include proper coaching, warm-up, officiation, legislation, medical expertise and protective gear. There are still many opportunities for prospective studies and other research projects among young athletes in various sports. Current studies will serve as a baseline for future research to assess the success of specific interventions in reducing the incidence of elbow injury in the paediatric athlete. Further epidemiological studies in various sports will help expand our knowledge and prevent potential disability and deformity in the paediatric elbow.

Can We Achieve Intuitive Prosthetic Elbow Control Based on Healthy Upper Limb Motor Strategies?

PubMed Central

Merad, Manelle; de Montalivet, Étienne; Touillet, Amélie; Martinet, Noël; Roby-Brami, Agnès; Jarrassé, Nathanaël

2018-01-01

Most transhumeral amputees report that their prosthetic device lacks functionality, citing the control strategy as a major limitation. Indeed, they are required to control several degrees of freedom with muscle groups primarily used for elbow actuation. As a result, most of them choose to have a one-degree-of-freedom myoelectric hand for grasping objects, a myoelectric wrist for pronation/supination, and a body-powered elbow. Unlike healthy upper limb movements, the prosthetic elbow joint angle, adjusted prior to the motion, is not involved in the overall upper limb movements, causing the rest of the body to compensate for the lack of mobility of the prosthesis. A promising solution to improve upper limb prosthesis control exploits the residual limb mobility: like in healthy movements, shoulder and prosthetic elbow motions are coupled using inter-joint coordination models. The present study aims to test this approach. A transhumeral amputated individual used a prosthesis with a residual limb motion-driven elbow to point at targets. The prosthetic elbow motion was derived from IMU-based shoulder measurements and a generic model of inter-joint coordinations built from healthy individuals data. For comparison, the participant also performed the task while the prosthetic elbow was implemented with his own myoelectric control strategy. The results show that although the transhumeral amputated participant achieved the pointing task with a better precision when the elbow was myoelectrically-controlled, he had to develop large compensatory trunk movements. Automatic elbow control reduced trunk displacements, and enabled a more natural body behavior with synchronous shoulder and elbow motions. However, due to socket impairments, the residual limb amplitudes were not as large as those of healthy shoulder movements. Therefore, this work also investigates if a control strategy whereby prosthetic joints are automatized according to healthy individuals' coordination models can lead to an intuitive and natural prosthetic control. PMID:29456499

Revision ulnar collateral ligament reconstruction using a suspension button fixation technique.

PubMed

Lee, Gregory H; Limpisvasti, Orr; Park, Maxwell C; McGarry, Michelle H; Yocum, Lewis A; Lee, Thay Q

2010-03-01

Revision ulnar collateral ligament reconstruction remains a challenging problem. The objective of this study was to biomechanically evaluate an ulnar collateral ligament reconstruction technique using a suspension button fixation technique that can be used even in the case of ulnar cortical bone loss. An ulnar suspension fixation technique for ulnar collateral ligament reconstruction can restore elbow kinematics and demonstrate failure strength comparable to that of currently available techniques. Controlled laboratory study. Nine pairs of cadaveric elbows were dissected free of soft tissue and potted. After simulating ulnar cortical bone loss, ulnar collateral ligament reconstruction was performed in 1 elbow of each pair using palmaris longus autograft and a 30-mm RetroButton suspended from the far (lateralmost) ulnar cortex. A docking technique was used for humeral fixation of the graft. Elbow valgus angle was quantified using a Microscribe 3DLX digitizer at multiple elbow flexion angles. Valgus angle was measured with the ulnar collateral ligament intact, transected, and reconstructed. In addition, load-to-failure testing was performed in 1 elbow of each pair. Release of the ulnar collateral ligament caused a significant increase in valgus angle at each flexion angle tested (P < .002). Reconstructed elbows demonstrated no significant differences in valgus angle from the intact elbow at all flexion angles tested. Load-to-failure tests showed that reconstructed elbows had an ultimate torque (10.3 + or - 5.7 N x m) significantly less than intact elbows (26.4 + or - 10.6 N x m) (P = .001). Ulnar collateral ligament reconstruction using a suspension button fixation technique reliably restored elbow kinematics to the intact state. Load-to-failure testing demonstrated comparable fixation strength to several historic controls of primary reconstruction techniques despite the simulated ulnar cortical bone loss. Ulnar collateral ligament reconstruction using a suspension button fixation technique can be considered in the case of ulnar cortical bone loss in a primary or revision setting.

Nursemaid's Elbow (For Parents)

MedlinePlus

... Parents Parents site Sitio para padres General Health Growth & Development Infections Diseases & Conditions Pregnancy & Baby Nutrition & Fitness Emotions & ... For Parents / Nursemaid's Elbow Print About Nursemaid's Elbow Toddlers and preschoolers are at risk for a common ...

Isometric torque-angle relationship and movement-related activity of human elbow flexors: implications for the equilibrium-point hypothesis.

PubMed

Hasan, Z; Enoka, R M

1985-01-01

Since the moment arms for the elbow-flexor muscles are longest at intermediate positions of the elbow and shorter at the extremes of the range of motion, it was expected that the elbow torque would also show a peak at an intermediate angle provided the activity of the flexor muscles remained constant. We measured the isometric elbow torque at different elbow angles while the subject attempted to keep constant the electromyographic activity (EMG) of the brachioradialis muscle. The torque-angle relationship thus obtained exhibited a peak, as expected, but the shape of the relationship varied widely among subjects. This was due in part to differences in the variation of the biceps brachii EMG with elbow angle among the different subjects. The implications of these observations for the equilibrium-point hypothesis of movement were investigated as follows. The subject performed elbow movements in the presence of an external torque (which tended to extend the elbow joint) provided by a weight-and-pulley arrangement. We found in the case of flexion movements that invariably there was a transient increase in flexor EMG, as would seem necessary for initiating the movement. However, the steady-state EMG after the movement could be greater or less than the pre-movement EMG. Specifically, the least flexor EMG was required for equilibrium in the intermediate range of elbow angles, compared to the extremes of the range of motion. The EMG-angle relationship, however, varied with the muscle and the subject. The observation that the directions of change in the transient and the steady-state EMG are independent of each other militates against the generality of the equilibrium-point hypothesis. However, a form of the hypothesis which includes the effects of the stretch reflex is not contradicted by this observation.

Floating elbow injuries in adults: prognostic factors affecting clinical outcomes.

PubMed

Ditsios, Konstantinos; Boutsiadis, Achilleas; Papadopoulos, Pericles; Karataglis, Dimitrios; Givissis, Panagiotis; Hatzokos, Ippokratis; Christodoulou, Anastasios

2013-01-01

Floating elbow fractures in adults are rare and complex injuries with unpredictable outcomes. The present study was designed to assess our experience, analyze possible compilations and illustrate prognostic factors of the final outcome. Between 2002 and 2009, 19 patients with floating elbow fractures were treated in our department (mean follow-up, 26 months). The fractures were open in 10 patients (52.6%), and concomitant nerve palsy was present in 10 patients. Although the term "floating elbow" refers only to concomitant ipsilateral humeral and forearm shaft fractures, we also included injuries with intra-articular involvement. We categorized the patients into 4 groups: group I (10 patients) included shaft fractures of humerus and forearm, group IIa (5 patients) and IIb (1 patient) included partial intra-articular injuries, and group III (3 patients) involved only intra-articular comminuted fractures of the elbow region. Fracture healing was observed 14 weeks postoperatively, except in 2 patients, in which elbow arthroplasty was applied, and in 1 with brachial artery injury. Nine patients with nerve neuropraxia recovered 4 months postoperatively, and tendon transfers were necessary in 1 patient. Recovery in patients with nerve palsy was worse than in those without nerve injury (Mayo Elbow Performance Score, 73 vs 88.34; Khalfayan score, 72 vs 88.3). In addition, intra-articular involvement (groups II and III) negatively influenced the final clinical outcome compared with isolated shaft fractures (group I; Mayo Elbow Performance Score, 71.1 vs 88.5; Khalfayan score, 72.67 vs 86.1). Although the nature of floating elbow injuries is complex, the presence of nerve injury and intra-articular involvement predispose to worse clinical outcomes. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Comparative study of phrenic and intercostal nerve transfers for elbow flexion after global brachial plexus injury.

PubMed

Liu, Yuzhou; Lao, Jie; Zhao, Xin

2015-04-01

Global brachial plexus injuries (BPIs) are devastating events frequently resulting in severe functional impairment. The widely used nerve transfer sources for elbow flexion in patients with global BPIs include intercostal and phrenic nerves. The aim of this study was to compare phrenic and intercostal nerve transfers for elbow flexion after global BPI. A retrospective review of 33 patients treated with phrenic and intercostal nerve transfer for elbow flexion in posttraumatic global root avulsion BPI was carried out. In the phrenic nerve transfer group, the phrenic nerve was transferred to the anterolateral bundle of the anterior division of the upper trunk (23 patients); in the intercostal nerve transfer group, three intercostal nerves were coapted to the anterolateral bundles of the musculocutaneous nerve. The British Medical Research Council (MRC) grading system, angle of elbow flexion, and electromyography (EMG) were used to evaluate the recovery of elbow flexion at least 3 years postoperatively. The efficiency of motor function in the phrenic nerve transfer group was 83%, while it was 70% in the intercostal nerve transfer group. The two groups were not statistically different in terms of the MRC grade (p=0.646) and EMG results (p=0.646). The outstanding rates of angle of elbow flexion were 48% and 40% in the phrenic and intercostal nerve transfer groups, respectively. There was no significant difference of outstanding rates in the angle of elbow flexion between the two groups. Phrenic nerve transfer had a higher proportion of good prognosis for elbow flexion than intercostal nerve transfer, but the effective and outstanding rate had no significant difference for biceps reinnervation between the two groups according to MRC grading, angle of elbow flexion, and EMG. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of elbow and forearm position on contact pressure between the extensor origin and the lateral side of the capitellum.

PubMed

Tanaka, Yoshitaka; Aoki, Mitsuhiro; Izumi, Tomoki; Wada, Takuro; Fujimiya, Mineko; Yamashita, Toshihiko

2011-01-01

Bone-to-tendon contact in the origin of the common extensor tendons is considered to be one of the causes of lateral epicondylitis. Some factors, including elbow and forearm position, varus stress to the elbow, or contraction of the wrist extensor tendons, are considered to affect this bone-to-tendon contact. However, no studies have evaluated the effect of the elbow and forearm position on bone-tendon interface. The purpose of this study is to evaluate the effect of the position of the elbow and forearm on the contact pressure of the tendinous origin of the common wrist and finger extensors. We used 8 fresh cadaveric upper extremities. Contact pressure between the origin of the common extensor tendons and the lateral side of the capitellum was measured with a pressure sensor and was compared among various conditions, including elbow flexion angle (0°, 30°, 60°, and 90°), forearm rotation position (neutral and 81.5° pronation position), and varus stress load of the elbow (none, gravity on the forearm, and gravity on the forearm +1.96 Nm). Contact pressure was also measured during tension force of the extensor carpi radialis longus, extensor carpi radialis brevis, and extensor digitorum communis by 0, 9.8, and 19.6 N. Contact pressure was significantly increased with the elbow extension position, forearm pronation position, and varus stress to the elbow under tension of the extensor carpi radialis longus or extensor carpi radialis brevis. This study provides data about the amount of contact pressure between bone and tendon at the origin of the common extensor tendons in the elbow. This information may lead to a better understanding of, and better treatment for, lateral epicondylitis. Copyright © 2011. Published by Elsevier Inc.

The effect of repetitive baseball pitching on medial elbow joint space gapping associated with 2 elbow valgus stressors in high school baseball players.

PubMed

Hattori, Hiroshi; Akasaka, Kiyokazu; Otsudo, Takahiro; Hall, Toby; Amemiya, Katsuya; Mori, Yoshihisa

2018-04-01

To prevent elbow injury in baseball players, various methods have been used to measure medial elbow joint stability with valgus stress. However, no studies have investigated higher levels of elbow valgus stress. This study investigated medial elbow joint space gapping measured ultrasonically resulting from a 30 N valgus stress vs. gravitational valgus stress after a repetitive throwing task. The study included 25 high school baseball players. Each subject pitched 100 times. The ulnohumeral joint space was measured ultrasonographically, before pitching and after each successive block of 20 pitches, with gravity stress or 30 N valgus stress. Two-way repeated measures analysis of variance and Pearson correlation coefficient analysis were used. The 30 N valgus stress produced significantly greater ulnohumeral joint space gapping than gravity stress before pitching and at each successive 20-pitch block (P < .01). For the 2 stress methods, ulnohumeral joint space gapping increased significantly from baseline after 60 pitches (P < .01). Strong significant correlations were found between the 2 methods for measurement of medial elbow joint space gapping (r = 0.727-0.859, P < .01). Gravity stress and 30 N valgus stress may produce different effects with respect to medial elbow joint space gapping before pitching; however, 30 N valgus stress appears to induce greater mechanical stress, which may be preferable when assessing joint instability but also has the potential to be more aggressive. The present results may indicate that constraining factors to medial elbow joint valgus stress matched typical viscoelastic properties of cyclic creep. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Is bipolar latissimus dorsi transfer a reliable option to restore elbow flexion in children with arthrogryposis? A review of 13 tendon transfers.

PubMed

Zargarbashi, Ramin; Nabian, Mohammad Hossein; Werthel, Jean-David; Valenti, Philippe

2017-11-01

Scant data are published about different available therapeutic options for restoration of active elbow flexion in arthrogryposis with varying degrees of improvement. In this retrospective study we evaluated medium-term effects of bipolar latissimus dorsi transfer in patients with arthrogryposis. Pedicled latissimus dorsi bipolar muscle transfer was used to restore elbow flexion in 11 patients (13 limbs) with arthrogryposis. Elbow and shoulder range of motions and strength of elbow flexion were measured preoperatively and at the last follow-up. The functional use of the upper limb was examined by observation of activities of daily living and presence of adaptive mechanisms. General satisfaction was assessed at the final follow-up. The patients were a mean age of 5.69 ± 2.49 years. The follow-up period was 27.31 ± 17.8 months. At the last examination, according to transferred muscle function and elbow range of motion, function of 12 limbs was graded as excellent and good, and 1 was graded poor. The active postoperative elbow range of motion was 97.7° ± 34.5°. The general satisfaction of the patients with the surgical results was 92.3%. Activities of daily living were improved in 10 of 13 limbs, but adaptive mechanisms were detected in all patients except 2 at the last follow-up. We suggest pedicled bipolar latissimus dorsi transfer as a reliable therapeutic option to restore active elbow flexion in arthrogryposis with acceptable results regarding regaining range of motion and patient satisfaction. Functional passive elbow range of motion and good quality of latissimus dorsi muscle preoperatively is mandatory. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Assessment of medial elbow laxity by gravity stress radiography: comparison of valgus stress radiography with gravity and a Telos stress device.

PubMed

Harada, Mikio; Takahara, Masatoshi; Maruyama, Masahiro; Nemoto, Tadanobu; Koseki, Kazuhiko; Kato, Yoshihiro

2014-04-01

Valgus instability was reported to be higher with the elbow in 60° of flexion, rather than in 30° of flexion, although there are no studies using valgus stress radiography by gravity (gravity radiography) with the elbow in 60° of flexion. Fifty-seven patients with medial elbow pain participated. For both elbows, valgus stress radiography by use of a Telos device (Telos radiography) and gravity radiography, with the elbow in 60° of flexion, were performed for the assessment of medial elbow laxity. In both radiographs, the medial elbow joint space (MJS) on the affected side was compared with that on the opposite side, and the increase in the MJS on the affected side was assessed. For the Telos radiographs, the mean MJS was 4.7 mm on the affected side and 4.0 mm on the opposite side, with the mean increase in the MJS on the affected side being 0.7 mm. For the gravity radiographs, the mean MJS was 5.0 mm on the affected side and 4.2 mm on the opposite side, with the mean increase in the MJS on the affected side being 0.8 mm. There were significant correlations between the Telos and gravity radiographs in the MJS on the affected side, the MJS on the opposite side, and the increase in the MJS on the affected side (respectively, P < .0001). There was also a high level of intraobserver and interobserver reliability for the assessment of the gravity radiographs. Gravity radiography is useful for assessment of medial elbow laxity, similar to Telos radiography. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Leaving No Worker Behind: Community Colleges Retrain the Michigan Workforce--and Themselves

ERIC Educational Resources Information Center

Hilliard, Tom

2011-01-01

In 2007, Michigan undertook a bold mission: to retrain tens of thousands of adults to qualify for jobs in emerging and expanding sectors of the economy. The state's proposal to jobless, dislocated, and low-income residents was simple but appealing: enroll in up to two years of postsecondary education, and Michigan would cover up to $5,000 in…

Comparison between real and modeled maregraphic data obtained using a simple dislocation model of the 27.02.2010 Chilian seismic source

NASA Astrophysics Data System (ADS)

Roger, J.; Simao, N.; Ruegg, J.-C.; Briole, P.; Allgeyer, S.

2010-05-01

On the 27th February 2010, a magnitude Mw=8.8 earthquake shook a wide part of Chile. It was the result of a release of energy due to a rupture on the subduction fault plane of the Pacific oceanic plate beneath the South-American plate. It generated a widespread tsunami that struck the whole Pacific Ocean Coasts. In addition to the numerous casualties and destructions fathered by the earthquake itself, the tsunami reached several meters high in some near-field locations inundating important urban areas (for example in Talcahano). In some far-field places as in the Marquesas Islands (FR), it reached several meters high too. This tsunami has been recorded by numerous coastal tide gages and DART buoys and, more particularly, some sea level records are available in the rupture area (Valparaiso, Talcahano, Arica, Ancud, Corral, Coquimbo). The aim of this study is to use a simple dislocation model determined from a moment tensor solution, aftershocks locations and GPS measurements, to calculate the initial offshore bottom deformation. This deformation is introduced in a tsunami propagation code to produce synthetic mareogramms on specific points that are compared to the real recorded maregraphic data.

Elbow-specific clinical rating systems: extent of established validity, reliability, and responsiveness.

PubMed

The, Bertram; Reininga, Inge H F; El Moumni, Mostafa; Eygendaal, Denise

2013-10-01

The modern standard of evaluating treatment results includes the use of rating systems. Elbow-specific rating systems are frequently used in studies aiming at elbow-specific pathology. However, proper validation studies seem to be relatively sparse. In addition, these scoring systems might not always be used for appropriate populations of interest. Both of these issues might give rise to invalid conclusions being reported in the literature. Our aim was to investigate the extent to which the available elbow-specific outcome measurement tools have been validated and the quality of the validation itself. We also aimed to provide characteristics of the populations used for validation of these scales to enable clinicians to use them appropriately. A literature search identified 17 studies of 12 different elbow-specific scoring systems. These were assessed for validity, reliability, and responsiveness characteristics. The quality of these assessments was rated according to the Consensus Based Standards for the Selection of Health Measurement Instruments (COSMIN) checklist criteria, a standardized and validated tool developed specifically for this purpose. Currently, the only elbow-specific rating system that is validated using high-quality methodology is the Oxford Elbow Score, a patient-administered outcome measure tool that has been validated on heterogeneous study populations. Other rating systems still have to be proven in the future to be as good as the Oxford Elbow Score for clinical or research purposes. Additional validation studies are needed. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Glenoid bone grafting in primary reverse total shoulder arthroplasty.

PubMed

Ernstbrunner, Lukas; Werthel, Jean-David; Wagner, Eric; Hatta, Taku; Sperling, John W; Cofield, Robert H

2017-08-01

Severe glenoid bone loss remains a challenge in patients requiring shoulder arthroplasty and may necessitate glenoid bone grafting. The purpose of this study was to determine results, complications, and rates of failure of glenoid bone grafting in primary reverse shoulder arthroplasty. Forty-one shoulders that underwent primary reverse arthroplasty between 2006 and 2013 with a minimum follow-up of 2 years (mean, 2.8 years; range, 2-6 years) were reviewed. Thirty-four (83%) received corticocancellous grafts and 7 (17%) structural grafts. Active range of motion and pain levels were significantly improved (P < .001), with mean American Shoulder and Elbow Surgeons score of 77, Simple Shoulder Test score of 9, and patient satisfaction of 93% at the most recent follow-up. Preoperative severe glenoid erosion and increasing body mass index were significantly associated with worse American Shoulder and Elbow Surgeons scores (P = .04). On radiographic evaluation, 7 patients (18%) had grade 1 or grade 2 glenoid lucency. Glenoid bone graft incorporation was observed in 31 patients (78%). Twelve patients (30%) suffered from grade 1 or grade 2 scapular notching. All of the patients with structural grafts showed graft incorporation and no signs of glenoid lucency. Although glenoid lucency, glenoid graft resorption, and scapular notching were present at short-term to midterm follow-up, none of the patients needed revision surgery. Primary reverse shoulder arthroplasty with glenoid reconstruction using bone graft relieved pain and restored shoulder function and stability. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

A Force-Velocity Relationship and Coordination Patterns in Overarm Throwing

PubMed Central

van den Tillaar, Roland; Ettema, Gertjan

2004-01-01

A force-velocity relationship in overarm throwing was determined using ball weights varying from 0.2 to 0.8 kg. Seven experienced handball players were filmed at 240 frames per second. Velocity of joints of the upper extremity and ball together with the force on the ball were derived from the data. A statistically significant negative relationship between force and maximal ball velocity, as well as between ball weight and maximal ball velocity was observed. Also, with increase of ball weight the total throwing movement time increased. No significant change in relative timing of the different joints was demonstrated, suggesting that the subjects did not change their “global ”coordination pattern (kinematics) within the tested range of ball weights. A simple model revealed that 67% of ball velocity at ball release was explained by the summation of effects from the velocity of elbow extension and internal rotation of the shoulder. With regard to the upper extremity the internal rotation of the shoulder and elbow extension are two important contributors to the total ball velocity at release. Key Points An inverse relationship between load and velocity and a linear force-velocity exists in overarm throwing with ball weights varying from 0.2 to 0.8 kg. Qualitatively, no changes in coordination pattern (relative timing) occur with increasing ball weight within the tested range of ball weights. The absolute throwing movement time increased with ball weight. Quantitatively, with regard to the upper extremity, the internal rotation of the shoulder and elbow extension are two important contributors to the total ball velocity at release. PMID:24624005

Medical diagnosis of cubital tunnel syndrome ameliorated with thrust manipulation of the elbow and carpals

PubMed Central

Kearns, Gary; Wang, Sharon

2012-01-01

This case report describes the effectiveness of thrust manipulation to the elbow and carpals in the management of a patient referred with a medical diagnosis of cubital tunnel syndrome (CuTS). The patient was a 45-year-old woman with a 6-week history of right medial elbow pain, ulnar wrist pain, and intermittent paresthesia in the ulnar nerve distribution. Upon initial assessment, she presented with a positive elbow flexion test and upper limb neurodynamic test with ulnar nerve bias. A biomechanical assessment of the elbow and carpals revealed a loss of lateral glide of the humerus on the ulna and a loss of palmar glide of the triquetral on the hamate. After the patient received two thrust manipulations of the elbow and one thrust manipulation of the carpals over the course of four sessions, her pain and paresthesia were resolved. This case demonstrates that the use of thrust manipulation to the elbow and carpals may be an effective approach in the management of insidious onset CuTS. This patient was successfully treated with thrust manipulation when joint dysfunction of the elbow and wrist were appropriately identified. This case report may shed light on the examination and management of insidious onset CuTS. PMID:23633888

Does the Length of Elbow Flexors and Visual Feedback Have Effect on Accuracy of Isometric Muscle Contraction in Men after Stroke?

PubMed Central

Juodzbaliene, Vilma; Darbutas, Tomas; Skurvydas, Albertas

2016-01-01

The aim of the study was to determine the effect of different muscle length and visual feedback information (VFI) on accuracy of isometric contraction of elbow flexors in men after an ischemic stroke (IS). Materials and Methods. Maximum voluntary muscle contraction force (MVMCF) and accurate determinate muscle force (20% of MVMCF) developed during an isometric contraction of elbow flexors in 90° and 60° of elbow flexion were measured by an isokinetic dynamometer in healthy subjects (MH, n = 20) and subjects after an IS during their postrehabilitation period (MS, n = 20). Results. In order to evaluate the accuracy of the isometric contraction of the elbow flexors absolute errors were calculated. The absolute errors provided information about the difference between determinate and achieved muscle force. Conclusions. There is a tendency that greater absolute errors generating determinate force are made by MH and MS subjects in case of a greater elbow flexors length despite presence of VFI. Absolute errors also increase in both groups in case of a greater elbow flexors length without VFI. MS subjects make greater absolute errors generating determinate force without VFI in comparison with MH in shorter elbow flexors length. PMID:27042670

Normative values of isometric elbow strength in healthy adults: a systematic review.

PubMed

Kotte, Shamala H P; Viveen, Jetske; Koenraadt, Koen L M; The, Bertram; Eygendaal, Denise

2018-07-01

Post-traumatic deformities such as biceps tendon rupture or (peri-)articular fractures of the elbow are often related to a decrease in muscle strength. Postoperative evaluation of these deformities requires normative values of elbow strength. The purpose of this systematic review was to determine these normative values of isometric elbow strength in healthy adults resulting from studies evaluating this strength (i.e. flexion, extension, pronation and supination strength). The databases of PubMed, EMBASE and Web of Sciences were searched and screened for studies involving the isometric elbow strength as measured in asymptomatic volunteers. The quality of the studies was assessed and studies of low quality were excluded. Nineteen studies met the inclusion criteria and were of sufficiently high quality to be included in the present review. In these studies, elbow strength was measured in a total of 1880 healthy volunteers. The experimental set-up and devices used to measure elbow strength varied between studies. Using some assumptions, a normative values table was assembled. Large standard deviations of normative values in combination with different measurement devices used, as well as the different measurement positions of the subjects, demonstrated that there is no consensus about measuring the isometric elbow strength and therefore the normative values have to be interpreted with caution.

Elbow Injuries and Disorders

MedlinePlus

... Many things can make your elbow hurt. A common cause is tendinitis, an inflammation or injury to the tendons that attach muscle to bone. Tendinitis of the elbow is a sports injury, often from playing tennis or golf. You ...

Elbow flexor and extensor muscle weakness in lateral epicondylalgia.

PubMed

Coombes, Brooke K; Bisset, Leanne; Vicenzino, Bill

2012-05-01

To evaluate whether deficits of elbow flexor and extensor muscle strength exist in lateral epicondylalgia (LE) in comparison with a healthy control population. Cross-sectional study. 150 participants with unilateral LE were compared with 54 healthy control participants. Maximal isometric elbow flexion and extension strength were measured bilaterally using a purpose-built standing frame such that gripping was avoided. The authors found significant side differences in elbow extensor (-6.54 N, 95% CI -11.43 to -1.65, p=0.008, standardised mean difference (SMD) -0.45) and flexor muscle strength (-11.26 N, 95% CI -19.59 to -2.94, p=0.009, SMD -0.46) between LE and control groups. Within the LE group, only elbow extensor muscle strength deficits between sides was significant (affected-unaffected: -2.94 N, 95% CI -5.44 to -0.44). Small significant deficits of elbow extensor and flexor muscle strength exist in the affected arm of unilateral LE in comparison with healthy controls. Notably, comparing elbow strength between the affected and unaffected sides in unilateral epicondylalgia is likely to underestimate these deficits. Trial Registration Australian New Zealand Clinical Trials Register ACTRN12609000051246.

Impingement of Droplets in 90 deg Elbows with Potential Flow

NASA Technical Reports Server (NTRS)

Hacker, Paul T.; Brun, Rinaldo J.; Boyd, Bemrose

1953-01-01

Trajectories were determined for droplets in air flowing through 90 deg elbows especially designed for two-dimensional potential motion with low pressure losses. The elbows were established by selecting as walls of each elbow two streamlines of the flow field produced by a complex potential function that establishes a two-dimensional flow around a 90 deg bend. An unlimited number of elbows with slightly different shapes can be established by selecting different pairs of streamlines as walls. The elbows produced by the complex potential function selected are suitable for use in aircraft air-intake ducts. The droplet impingement data derived from the trajectories are presented along with equations in such a manner that the collection efficiency, the area, the rate, and the distribution of droplet impingement can be determined for any elbow defined by any pair of streamlines within a portion of the flow field established by the complex potential function. Coordinates for some typical streamlines of the flow field and velocity components for several points along these streamlines are presented in tabular form.

Humeral Torsion as a Risk Factor for Shoulder and Elbow Injury in Professional Baseball Pitchers.

PubMed

Noonan, Thomas J; Thigpen, Charles A; Bailey, Lane B; Wyland, Douglas J; Kissenberth, Michael; Hawkins, Richard J; Shanley, Ellen

2016-09-01

Numerous studies have demonstrated that humeral retrotorsion is increased in the dominant arms of throwing athletes. No study has clearly defined the relationship between humeral retrotorsion and shoulder and elbow injury. Uninjured professional pitchers will display more dominant humeral torsion (HT) than professional pitchers who sustain shoulder injuries but less than pitchers who sustain elbow injuries. Case-control study; Level of evidence, 3. Pitchers from the Colorado Rockies professional baseball organization were recruited for participation for this prospective injury study from 2009 to 2013. HT was assessed using indirect ultrasonographic techniques and was measured prospectively in 255 pitchers before each spring training (average of 2 trials). From the beginning of the preseason to the end of the postseason, overuse upper extremity injuries (shoulder or elbow) were tracked for each participating athlete. All athletes who reported pain or injury to their coach were referred to the organization's athletic trainer for evaluation and classification of each injury. The difference in HT was calculated by subtracting measurement of the dominant arm from the nondominant arm, and 3 separate mixed-model analyses of variance (side × injury group) were used to compare the dominant and nondominant HT between all pitchers who developed an arm injury (shoulder and elbow combined), as well as comparing pitchers who developed a shoulder or elbow injury to those who did not miss games due to shoulder or elbow injury (α = .05). During the course of the study, 60 arm (30 shoulder; 30 elbow) injuries were observed; 195 pitchers did not suffer an injury. There were no differences when HT was compared between all injured (shoulder and elbow injuries combined) and uninjured pitchers (P = .13; effect size 0.14). There was a significant interaction effect showing that pitchers who suffered a shoulder injury displayed 4° less dominant humeral retrotorsion compared with pitchers without injury (P = .04) and that pitchers with elbow injury displayed 5° greater humeral retrotorsion (P = .04). In addition, those who suffered an ulnar collateral ligament injury requiring reconstruction (n = 17) also displayed 4(o) greater dominant retrotorsion and 5° less nondominant humeral retrotorsion compared with pitchers who did not suffer an injury (n = 195; P = .05). There was not a significant difference between nondominant HT among pitchers who sustained shoulder and elbow injuries and pitchers without injury. The results of this study show a contrast in dominant humeral retrotorsion between pitchers who suffered shoulder and elbow injuries compared with those without an injury. Pitchers who sustained shoulder injuries had less dominant humeral retrotorsion compared with noninjured pitchers. In contrast, pitchers who sustained time-loss elbow injuries displayed increased humeral retrotorsion compared with noninjured pitchers. Together, these results suggest that increased adaptive humeral retrotorsion is protective against shoulder injuries but a harmful contributor for elbow injuries in professional pitchers. This is the first study to show differing injury risk profiles for shoulder and elbow injury. © 2016 The Author(s).

Natural course in tennis elbow--lateral epicondylitis after all?

PubMed

Zeisig, Eva

2012-12-01

Tennis elbow is a common and difficult-to-treat condition largely because of lack of evidence. The natural history is unknown, but the condition is described as self-limiting. The objective of this case report is to describe the natural course of two control participants (pain free), who later developed tennis elbow, patient history, clinical findings, and ultrasound and colour Doppler examination before, during and after a period of tennis elbow.

Accuracy of visual estimates of joint angle and angular velocity using criterion movements.

PubMed

Morrison, Craig S; Knudson, Duane; Clayburn, Colby; Haywood, Philip

2005-06-01

A descriptive study to document undergraduate physical education majors' (22.8 +/- 2.4 yr. old) estimates of sagittal plane elbow angle and angular velocity of elbow flexion visually was performed. 42 subjects rated videotape replays of 30 movements organized into three speeds of movement and two criterion elbow angles. Video images of the movements were analyzed with Peak Motus to measure actual values of elbow angles and peak angular velocity. Of the subjects 85.7% had speed ratings significantly correlated with true peak elbow angular velocity in all three angular velocity conditions. Few (16.7%) subjects' ratings of elbow angle correlated significantly with actual angles. Analysis of the subjects with good ratings showed the accuracy of visual ratings was significantly related to speed, with decreasing accuracy for slower speeds of movement. The use of criterion movements did not improve the small percentage of novice observers who could accurately estimate body angles during movement.

Finite Element Analysis and Experimental Study on Elbow Vibration Transmission Characteristics

NASA Astrophysics Data System (ADS)

Qing-shan, Dai; Zhen-hai, Zhang; Shi-jian, Zhu

2017-11-01

Pipeline system vibration is one of the significant factors leading to the vibration and noise of vessel. Elbow is widely used in the pipeline system. However, the researches about vibration of elbow are little, and there is no systematic study. In this research, we firstly analysed the relationship between elbow vibration transmission characteristics and bending radius by ABAQUS finite element simulation. Then, we conducted the further vibration test to observe the vibration transmission characteristics of different elbows which have the same diameter and different bending radius under different flow velocity. The results of simulation calculation and experiment both showed that the vibration acceleration levels of the pipeline system decreased with the increase of bending radius of the elbow, which was beneficial to reduce the transmission of vibration in the pipeline system. The results could be used as reference for further studies and designs for the low noise installation of pipeline system.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nesterova, E.V.; Bouvier, S.; Bacroix, B.

Transmission electron microscopy (TEM) microstructures of a high-strength dual-phase steel DP800 have been examined after moderate plastic deformations in simple shear and uniaxial tension. Special attention has been paid to the effect of the intergranular hard phase (martensite) on the microstructure evolution in the near-grain boundary regions. Quantitative parameters of dislocation patterning have been determined and compared with the similar characteristics of previously examined single-phase steels. The dislocation patterning in the interiors of the ferrite grains in DP800 steel is found to be similar to that already observed in the single-phase IF (Interstitial Free) steel whereas the martensite-affected zones presentmore » a delay in patterning and display very high gradients of continuous (gradual) disorientations associated with local internal stresses. The above stresses are shown to control the work-hardening of dual-phase materials at moderate strains for monotonic loading and are assumed to influence their microstructure evolution and mechanical behavior under strain-path changes. - Highlights: • The microstructure evolution has been studied by TEM in a DP800 steel. • It is influenced by both martensite and dislocations in the initial state. • The DP800 steel presents a high work-hardening rate due to internal stresses.« less

EBIC investigation of hydrogenation of crystal defects in EFG solar silicon ribbons

NASA Technical Reports Server (NTRS)

Sullivan, T.; Ast, D. G.

1983-01-01

Changes in the contrast and resolution of defect structures in 205 Ohm-cm EFG polysilicon ribbon subjected to annealing and hydrogenation treatments were observed in a JEOL 733 Superprobe scanning electron microscope, using electron beam induced current (EBIC) collected at an A1 Schottky barrier. The Schottky barrier was formed by evaporation of A1 onto the cleaned and polished surface of the ribbon material. Measurement of beam energy, beam current, and the current induced in the Schottky diode enabled observations to be quantified. Exposure to hydrogen plasma increased charge collection efficiency. However, no simple causal relationship between the hydrogenation and charge collection efficiency could be inferred, because the collection efficiency also displayed an unexpected thermal dependence. Good quality intermediate-magnification (1000X-5400X) EBIC micrographs of several specific defect structures were obtained. Comparison of grown-in and stress-induced dislocations after annealing in vacuum at 500 C revealed that stress-induced dislocations are hydrogenated to a much greater degree than grown-in dislocations. The theoretical approximations used to predict EBIC contrast and resolution may not be entirely adequate to describe them under high beam energy and low beam current conditions.

Effect of orientation of prismatic dislocation loops on interaction with free surfaces in BCC iron

NASA Astrophysics Data System (ADS)

Fikar, Jan; Gröger, Roman; Schäublin, Robin

2017-12-01

The prismatic loops appear in metals as a result of high-energy irradiation. Understanding their formation and interaction is important for quantification of irradiation-induced deterioration of mechanical properties. Characterization of dislocation loops in thin foils is commonly made using transmission electron microscopy (TEM), but the results are inevitably influenced by the proximity of free surfaces. The prismatic loops are attracted to free surfaces by image forces. Depending on the type, shape, size, orientation and depth of the loop in the foil, they can escape to the free surface creating denuded loop-free zones and thus invalidating TEM observations. In our previous studies we described a simple general method to determine the critical depth and the critical stress to move prismatic dislocation loops. The critical depths can be further used to correct measurements of the loop density by TEM. Here, we use this procedure to compare 〈100〉 loops and 1/2 〈111〉 loops in body-centered cubic (BCC) iron. The influences of the interatomic potential and the loop orientation are studied in detail. The difference between interstitial and vacancy type loop is also investigated.

Racquet string tension directly affects force experienced at the elbow: implications for the development of lateral epicondylitis in tennis players

PubMed Central

Mohandhas, Badri R; Makaram, Navnit; Drew, Tim S; Wang, Weijie; Arnold, Graham P

2016-01-01

Background Lateral epicondylitis (LE) occurs in almost half of all tennis players. Racket-string tension is considered to be an important factor influencing the development of LE. No literature yet exists that substantiates how string-tension affects force transmission to the elbow, as implicated in LE development. We establish a quantitative relationship between string-tension and elbow loading, analyzing tennis strokes using rackets with varying string-tensions. Methods Twenty recreational tennis players simulated backhand tennis strokes using three rackets strung at tensions of 200 N, 222 N and 245 N. Accelerometers recorded accelerations at the elbow, wrist and racket handle. Average peak acceleration was determined to correlate string-tension with elbow loading. Results Statistically significant differences (p < 0.05) were observed when average peak acceleration at the elbow at 200 N string-tension (acceleration of 5.58 m/s2) was compared with that at 222 N tension (acceleration of 6.83 m/s2) and 245 N tension (acceleration of 7.45 m/s2). The 200 N racket induced the least acceleration at the elbow. Conclusions Although parameters determining force transmission to the elbow during a tennis stroke are complex, the present study was able to control these parameters, isolating the effect of string-tension. Lower string-tensions transmit less force to the elbow in backhand strokes. Reducing string-tension should be considered favourably with respect to reducing the risk of developing LE. PMID:27583017

The "moving valgus stress test" for medial collateral ligament tears of the elbow.

PubMed

O'Driscoll, Shawn W M; Lawton, Richard L; Smith, Adam M

2005-02-01

The diagnosis of a painful partial tear of the medial collateral ligament in overhead-throwing athletes is challenging, even for experienced elbow surgeons and despite the use of sophisticated imaging techniques. The "moving valgus stress test" is an accurate physical examination technique for diagnosis of medial collateral ligament attenuation in the elbow. Cohort study (diagnosis); Level of evidence, 2. Twenty-one patients underwent surgical intervention for medial elbow pain due to medial collateral ligament insufficiency or other abnormality of chronic valgus overload, and they were assessed preoperatively with an examination called the moving valgus stress test. To perform the moving valgus stress test, the examiner applies and maintains a constant moderate valgus torque to the fully flexed elbow and then quickly extends the elbow. The test is positive if the medial elbow pain is reproduced at the medial collateral ligament and is at maximum between 120 degrees and 70 degrees. The moving valgus stress test was highly sensitive (100%, 17 of 17 patients) and specific (75%, 3 of 4 patients) when compared to assessment of the medial collateral ligament by surgical exploration or arthroscopic valgus stress testing. The mean shear range (ie, the arc within which pain was produced with the moving valgus stress test) was 120 degrees to 70 degrees. The mean angle at which pain was at a maximum was 90 degrees of elbow flexion. The moving valgus stress test is an accurate physical examination technique that, when performed and interpreted correctly, is highly sensitive for medial elbow pain arising from the medial collateral ligament.

Isokinetic profile of elbow flexion and extension strength in elite junior tennis players.

PubMed

Ellenbecker, Todd S; Roetert, E Paul

2003-02-01

Descriptive study. To determine whether bilateral differences exist in concentric elbow flexion and extension strength in elite junior tennis players. The repetitive nature of tennis frequently produces upper extremity overuse injuries. Prior research has identified tennis-specific strength adaptation in the dominant shoulder and distal upper extremity musculature of elite players. No previous study has addressed elbow flexion and extension strength. Thirty-eight elite junior tennis players were bilaterally tested for concentric elbow flexion and extension muscle performance on a Cybex 6000 isokinetic dynamometer at 90 degrees/s, 210 degrees/s, and 300 degrees/s. Repeated-measures ANOVAs were used to test for differences between extremities, muscle groups, and speed. Significantly greater (P<0.002) dominant-arm elbow extension peak torque values were measured at 90 degrees/s, 210 degrees/s, and 300 degrees/s for males. Significantly greater (P<0.002) dominant-arm single-repetition work values were also measured at 90 degrees/s and 210 degrees/s for males. No significant difference was measured between extremities in elbow flexion muscular performance in males and for elbow flexion or extension peak torque and single-repetition work values in females. No significant difference between extremities was measured in elbow flexion/extension strength ratios in females and significant differences between extremities in this ratio were only present at 210 degrees/s in males (P<0.002). These data indicate muscular adaptations around the dominant elbow in male elite junior tennis players but not females. These data have ramifications for clinicians rehabilitating upper extremity injuries in patients from this population.

Functional Results in Arthroscopic Treatment in Patients with Chronic Lateral Elbow Pain.

PubMed

Phorkhar, Termphong; Chanlalit, Cholawish

2015-11-01

Modern surgery as elbow arthroscopic surgery is an accepted operation due to benefit in precise intra-articular lesion detection and minimally invasive surgery. To report the functional results when using arthroscopic surgery to treat chronic lateral elbow pain. The data was collected from 25 patients with chronic lateral elbow pain that failed in non-operative treatment and treated with elbow arthroscopic surgery. Five patients were excluded from this study due to diagnosed as instability that needed the ligament reconstruction. The etiology of pain were grouped in to tennis elbow (4 pts), plica (9 pts), tennis elbow combined with plica (4 pts) and cartilage lesion (3 pts). Thai quick DASH questionnaire was used to evaluate the functional results by comparing pre and post operation score and calculated statistic results with paired t-test by level of significance p < 0.05. The mean follow-up after surgery was 22 months by mean disability module pre and post-operative score is 68 and 18 respectively. In the occupation module was 74 and 25 respectively and in sports module was 81 and 17 respectively. All modules, scores was significant improved with p-value = 0.000, 0.000 and 0.004 respectively. The disability mean score in pre and post-operative along the diagnosis, tennis elbow mean score was 74 and 33, in plica lesion mean score was 65 and 11, combined lesions mean score was 60 and 18 and cartilage lesion mean score was 60 and 20. Approaching chronic lateral elbow pain with arthroscopy can maintain the signficant improvement of functional result in midterm follow-up.

Changes in head and neck position have a greater effect on elbow joint position sense in people with whiplash-associated disorders.

PubMed

Knox, Joanna Joy; Beilstein, Darren Jay; Charles, Scott Darren; Aarseth, Geir Arne; Rayar, Shivanthi; Treleaven, Julia; Hodges, Paul William

2006-01-01

It has been shown that perception of elbow joint position is affected by changes in head and neck position. Further, people with whiplash-associated disorders (WAD) present with deficits in upper limb coordination and movement. This study is aimed to determine whether the effect of changes in head position on elbow joint position error (JPE) is more pronounced in people with WAD, and to determine whether this is related to the participant's pain and anxiety levels. Nine people with chronic and disabling WAD and 11 healthy people participated in this experiment. The ability to reproduce a position at the elbow joint was assessed after changes in the position of the head and neck to 30 degrees , and with the head in the midline. Pain was monitored in WAD participants. Absolute elbow JPE with the head in neutral was not different between WAD and control participants (P=0.5). Changes in the head and neck position increased absolute elbow JPE in the WAD group (P<0.05), but did not affect elbow JPE in the control group (P=0.4). There was a connection between pain during testing and the effect of changes in head position on elbow JPE (P<0.05). Elbow JPE is affected by movement of the head and neck, with smaller angles of neck rotation in people with WAD than in healthy individuals. This observation may explain deficits in upper limb coordination in people with WAD, which may be due to the presence of pain or reduced range of motion in this population.

Single-stage Reconstruction of Elbow Flexion Associated with Massive Soft-Tissue Defect Using the Latissimus Dorsi Muscle Bipolar Rotational Transfer

PubMed Central

Cuéllar, Vanessa G.; Ghiassi, Alidad; Sharpe, Frances

2016-01-01

Introduction: In the upper extremity, the latissimus dorsi muscle can be used as an ipsilateral rotational muscle flap for soft-tissue coverage or functional reconstruction of arm and elbow. Patients who have both major soft-tissue loss and functional deficits can be successfully treated with a single-stage functional latissimus dorsi rotational muscle transfer that provides simultaneous soft-tissue coverage and functional reconstruction. Methods: Our data base was queried for all patients undergoing a rotational latissimus dorsi muscle transfer for simultaneous soft-tissue coverage and functional reconstruction of elbow flexion. Four patients were identified. A chart review documented the mechanism of injury, associated injuries, soft-tissue defect size, number of surgical procedures, length of follow-up, last elbow range of motion, and flexion strength. Results: Four patients with loss of elbow flexion due to traumatic loss of the anterior compartment muscles and the overlying soft tissue underwent simultaneous soft-tissue coverage and elbow flexorplasty using the ipsilateral latissimus dorsi as a bipolar muscle rotational tissue transfer. All flaps survived and had a recovery of Medical Research Council Grade 4/5 elbow flexion strength. No additional procedures were required for elbow flexion. The surgical technique is described and supplemented with surgical technique video and patient outcome. Conclusions: This patient series augments the data provided in other series supporting the safety and efficacy of this procedure which provides both soft-tissue coverage and functional restoration of elbow flexion as a single-stage procedure in the setting of massive traumatic soft-tissue loss of the arm. PMID:27757363

Single-stage Reconstruction of Elbow Flexion Associated with Massive Soft-Tissue Defect Using the Latissimus Dorsi Muscle Bipolar Rotational Transfer.

PubMed

Stevanovic, Milan V; Cuéllar, Vanessa G; Ghiassi, Alidad; Sharpe, Frances

2016-09-01

In the upper extremity, the latissimus dorsi muscle can be used as an ipsilateral rotational muscle flap for soft-tissue coverage or functional reconstruction of arm and elbow. Patients who have both major soft-tissue loss and functional deficits can be successfully treated with a single-stage functional latissimus dorsi rotational muscle transfer that provides simultaneous soft-tissue coverage and functional reconstruction. Our data base was queried for all patients undergoing a rotational latissimus dorsi muscle transfer for simultaneous soft-tissue coverage and functional reconstruction of elbow flexion. Four patients were identified. A chart review documented the mechanism of injury, associated injuries, soft-tissue defect size, number of surgical procedures, length of follow-up, last elbow range of motion, and flexion strength. Four patients with loss of elbow flexion due to traumatic loss of the anterior compartment muscles and the overlying soft tissue underwent simultaneous soft-tissue coverage and elbow flexorplasty using the ipsilateral latissimus dorsi as a bipolar muscle rotational tissue transfer. All flaps survived and had a recovery of Medical Research Council Grade 4/5 elbow flexion strength. No additional procedures were required for elbow flexion. The surgical technique is described and supplemented with surgical technique video and patient outcome. This patient series augments the data provided in other series supporting the safety and efficacy of this procedure which provides both soft-tissue coverage and functional restoration of elbow flexion as a single-stage procedure in the setting of massive traumatic soft-tissue loss of the arm.

78 FR 68907 - Agency Information Collection (Elbow and Forearm Conditions Disability Benefits Questionnaire...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-15

... Forearm Conditions Disability Benefits Questionnaire) Under OMB Review AGENCY: Veterans Benefits... Control No. 2900- NEW (Elbow and Forearm Conditions Disability Benefits Questionnaire)'' in any... Benefits Questionnaire)''. SUPPLEMENTARY INFORMATION: Title: Elbow and Forearm Conditions Disability...

Deficits in glenohumeral passive range of motion increase risk of elbow injury in professional baseball pitchers: a prospective study.

PubMed

Wilk, Kevin E; Macrina, Leonard C; Fleisig, Glenn S; Aune, Kyle T; Porterfield, Ron A; Harker, Paul; Evans, Timothy J; Andrews, James R

2014-09-01

Injuries to the elbow joint in baseball pitchers appear common. There appears to be a correlation between shoulder range of motion and elbow injuries. To prospectively determine whether decreased ROM of the throwing shoulder is correlated with the onset of elbow injuries in professional baseball pitchers. Cohort study; Level of evidence, 2. For 8 consecutive years (2005-2012), passive range of motion of both the throwing and nonthrowing shoulders of all major and minor league pitchers within a single professional baseball organization were measured by using a bubble goniometer during spring training. In total, 505 examinations were conducted on 296 pitchers. Glenohumeral external rotation and internal rotation were assessed in the supine position with the arm at 90° of abduction and in the plane of the scapula. The scapula was stabilized per methods previously established. Total rotation was defined as the sum of external rotation and internal rotation. Passive shoulder flexion was assessed with the subject supine and the scapula stabilized per methods previously established. Elbow injuries and days missed because of elbow injuries were assessed and recorded by the medical staff of the team. Throwing and nonthrowing shoulder measurements were compared by using Student t tests; 1-tailed Fisher exact tests were performed to identify significant associations between shoulder motion and elbow injury. Nominal logistic regression was performed to determine the odds of elbow injury. Significant differences were noted during side-to-side comparisons within subjects. There were 49 elbow injuries and 8 surgeries in 38 players, accounting for a total of 2551 days missed. Neither glenohumeral internal rotation deficit nor external rotation insufficiency was correlated with elbow injuries. Pitchers with deficits of >5° in total rotation in their throwing shoulders had a 2.6 times greater risk for injury. Pitchers with deficit of ≥5° in flexion of the throwing shoulder had a 2.8 times greater risk for injury. Bilateral differences in shoulder total rotation and flexion had a significant effect on the risk for elbow injuries in pitchers. Clinicians need to be aware of these findings and plan preventive programs that address these issues in hopes of reducing elbow injuries. © 2014 The Author(s).

Intraoperative Physical Examination for Diagnosis of Interosseous Ligament Rupture-Cadaveric Study.

PubMed

Kachooei, Amir Reza; Rivlin, Michael; Wu, Fei; Faghfouri, Aram; Eberlin, Kyle R; Ring, David

2015-09-01

To study the intraobserver and interobserver reliability of the diagnosis of interosseous ligament (IOL) rupture in a cadaver model. On 12 fresh frozen cadavers, radial heads were cut using an identical incision and osteotomy. After randomization, the soft tissues of the limbs were divided into 4 groups: both IOL and triangular fibrocartilage (TFCC) intact; IOL disruption but TFCC intact; both IOL and TFCC divided; and IOL intact but TFCC divided. All incisions had identical suturing. After standard instruction and demonstration of radius pull-push and radius lateral pull tests, 10 physician evaluators with different levels of experience examined the cadaver limbs in a standardized way (elbow at 90° with the forearm held in both supination and pronation) and were asked to classify them into one of the 4 groups. Next, the same examiners were asked to re-examine the limbs after randomly changing the order of examination. The interobserver reliability of agreement for the diagnosis of IOL injury (groups 2 and 3) was fair in both rounds of examination and the intraobserver reliability was moderate. The intra- and interobserver reliabilities of agreement for the 4 groups of injuries among the examiners were fair in both rounds of examination. The sensitivity, specificity, accuracy, positive, and negative predictive values were all around 70%. The likelihood of a positive test corresponding with the presence of IOL rupture (positive likelihood ratio) was 2.2. The likelihood of a negative test correctly diagnosing an intact IOL was 0.40. In cadavers, intraoperative tests had fair reliability and 70% accuracy for the diagnosis of IOL rupture using the push-pull and lateral pull maneuvers. The level of experience did not have any effect on the correct diagnosis of intact versus disrupted IOL. Although not common, some failure of surgeries for traumatic elbow fracture-dislocations is because of failure in timely diagnosis of IOL disruption. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Results of revision anterior shoulder stabilization surgery in adolescent athletes.

PubMed

Blackman, Andrew J; Krych, Aaron J; Kuzma, Scott A; Chow, Roxanne M; Camp, Christopher; Dahm, Diane L

2014-11-01

The purpose of this study was to determine failure rates, functional outcomes, and risk factors for failure after revision anterior shoulder stabilization surgery in high-risk adolescent athletes. Adolescent athletes who underwent primary anterior shoulder stabilization were reviewed. Patients undergoing subsequent revision stabilization surgery were identified and analyzed. Failure rates after revision surgery were assessed by Kaplan-Meier analysis. Failure was defined as recurrent instability requiring reoperation. Functional outcomes included the Marx activity score; American Shoulder and Elbow Surgeons score; and University of California, Los Angeles score. The characteristics of patients who required reoperation for recurrent instability after revision surgery were compared with those of patients who required only a single revision to identify potential risk factors for failure. Of 90 patients who underwent primary anterior stabilization surgery, 15 (17%) had failure and underwent revision surgery (mean age, 16.6 years; age range, 14 to 18 years). The mean follow-up period was 5.5 years (range, 2 to 12 years). Of the 15 revision patients, 5 (33%) had recurrent dislocations and required repeat revision stabilization surgery at a mean of 50 months (range, 22 to 102 months) after initial revision. No risk factors for failure were identified. The Kaplan-Meier reoperation-free estimates were 86% (95% confidence interval, 67% to 100%) at 24 months and 78% (95% confidence interval, 56% to 100%) at 48 months after revision surgery. The mean final Marx activity score was 14.8 (range, 5 to 20); American Shoulder and Elbow Surgeons score, 82.1 (range, 33 to 100); and University of California, Los Angeles score, 30.8 (range, 16 to 35). At 5.5 years' follow-up, adolescent athletes had a high failure rate of revision stabilization surgery and modest functional outcomes. We were unable to convincingly identify specific risk factors for failure of revision surgery. Level IV, retrospective therapeutic case series. Copyright © 2014 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

The application of an atomistic J-integral to a ductile crack.

PubMed

Zimmerman, Jonathan A; Jones, Reese E

2013-04-17

In this work we apply a Lagrangian kernel-based estimator of continuum fields to atomic data to estimate the J-integral for the emission dislocations from a crack tip. Face-centered cubic (fcc) gold and body-centered cubic (bcc) iron modeled with embedded atom method (EAM) potentials are used as example systems. The results of a single crack with a K-loading compare well to an analytical solution from anisotropic linear elastic fracture mechanics. We also discovered that in the post-emission of dislocations from the crack tip there is a loop size-dependent contribution to the J-integral. For a system with a finite width crack loaded in simple tension, the finite size effects for the systems that were feasible to compute prevented precise agreement with theory. However, our results indicate that there is a trend towards convergence.

High temperature lined conduits, elbows and tees

DOEpatents

De Feo, Angelo; Drewniany, Edward

1982-01-01

A high temperature lined conduit comprising, a liner, a flexible insulating refractory blanket around and in contact with the liner, a pipe member around the blanket and spaced therefrom, and castable rigid refractory material between the pipe member and the blanket. Anchors are connected to the inside diameter of the pipe and extend into the castable material. The liner includes male and female slip joint ends for permitting thermal expansion of the liner with respect to the castable material and the pipe member. Elbows and tees of the lined conduit comprise an elbow liner wrapped with insulating refractory blanket material around which is disposed a spaced elbow pipe member with castable refractory material between the blanket material and the elbow pipe member. A reinforcing band is connected to the elbow liner at an intermediate location thereon from which extend a plurality of hollow tubes or pins which extend into the castable material to anchor the lined elbow and permit thermal expansion. A method of fabricating the high temperature lined conduit, elbows and tees is also disclosed which utilizes a polyethylene layer over the refractory blanket after it has been compressed to maintain the refractory blanket in a compressed condition until the castable material is in place. Hot gases are then directed through the interior of the liner for evaporating the polyethylene and setting the castable material which permits the compressed blanket to come into close contact with the castable material.

Compensating for intersegmental dynamics across the shoulder, elbow, and wrist joints during feedforward and feedback control.

PubMed

Maeda, Rodrigo S; Cluff, Tyler; Gribble, Paul L; Pruszynski, J Andrew

2017-10-01

Moving the arm is complicated by mechanical interactions that arise between limb segments. Such intersegmental dynamics cause torques applied at one joint to produce movement at multiple joints, and in turn, the only way to create single joint movement is by applying torques at multiple joints. We investigated whether the nervous system accounts for intersegmental limb dynamics across the shoulder, elbow, and wrist joints during self-initiated planar reaching and when countering external mechanical perturbations. Our first experiment tested whether the timing and amplitude of shoulder muscle activity account for interaction torques produced during single-joint elbow movements from different elbow initial orientations and over a range of movement speeds. We found that shoulder muscle activity reliably preceded movement onset and elbow agonist activity, and was scaled to compensate for the magnitude of interaction torques arising because of forearm rotation. Our second experiment tested whether elbow muscles compensate for interaction torques introduced by single-joint wrist movements. We found that elbow muscle activity preceded movement onset and wrist agonist muscle activity, and thus the nervous system predicted interaction torques arising because of hand rotation. Our third and fourth experiments tested whether shoulder muscles compensate for interaction torques introduced by different hand orientations during self-initiated elbow movements and to counter mechanical perturbations that caused pure elbow motion. We found that the nervous system predicted the amplitude and direction of interaction torques, appropriately scaling the amplitude of shoulder muscle activity during self-initiated elbow movements and rapid feedback control. Taken together, our results demonstrate that the nervous system robustly accounts for intersegmental dynamics and that the process is similar across the proximal to distal musculature of the arm as well as between feedforward (i.e., self-initiated) and feedback (i.e., reflexive) control. NEW & NOTEWORTHY Intersegmental dynamics complicate the mapping between applied joint torques and the resulting joint motions. We provide evidence that the nervous system robustly predicts these intersegmental limb dynamics across the shoulder, elbow, and wrist joints during reaching and when countering external perturbations. Copyright © 2017 the American Physiological Society.

Romantic Resonances in the Rhetoric of Peter Elbow's "Writing Without Teachers."

ERIC Educational Resources Information Center

Yager, Kristi

1996-01-01

Seeks to uncover the historical roots within English Romanticism of Peter Elbow's thinking in order to show the depth and complexity of his assumptions about writing. Implicitly refutes charges questioning the intellectual credibility of Elbow's work. (TB)

The co-evolution of microstructure features in self-ion irradiated HT9 at very high damage levels

NASA Astrophysics Data System (ADS)

Getto, Elizabeth Margaret

The objective of this study was to understand the co-evolution of microstructure features in self-ion irradiated HT9 at very high damage levels. HT9 (heat 84425) was pre-implanted with 10 atom parts per million helium and then irradiated with 5 MeV Fe++ in the temperature range of 440-480°C to 188 dpa. A damage dependence study from 75 to 650 dpa was performed at the peak swelling temperature of 460°C. The swelling, dislocation and precipitate evolution was determined using Analytic Electron Microscopes in both Conventional Transmission electron microscopy (CTEM) and Scanning Transmission Electron Microscopy (STEM) modes. Void swelling reached a nominally linear rate of 0.03%/dpa from 188 to 650 dpa at 460°C. G phase precipitates were observed by 75 dpa and grew linearly up to 650 dpa. M 2X was observed by 250 dpa and peaked in volume fraction at 450 dpa. Dislocation loop evolution was observed up to 650 dpa including a step change in diameter between 375 and 450 dpa; which correlated with nucleation and growth of M2X. The experimental results were interpreted using a rate theory model, the Radiation Induced Microstructure Evolution (RIME), in the damage range from 188 to 650 dpa. A simple system of voids and dislocations was modeled in which the dislocations measured from experiment were used as input, or the dislocations were allowed to evolve dynamically, resulting in swelling that was overestimated by 63% relative to that observed experimentally. G phase had limited effect on the void or dislocation behavior. The behavior of M2X within the microstructure was characterized as a direct effect as a coherent sink, and as an indirect effect in consuming carbon from the matrix, which had the largest impact on both void and dislocation behavior. A slowly monotonically increasing swelling rate was observed both experimentally and computationally, with swelling rates of ˜0.025%/dpa and ˜0.036%/dpa before and after 450 dpa. The agreement in void behavior between experiment and model when all effects (loops, network, G phase, M2X formation and growth, and removal of carbon) are accounted for demonstrates the importance of characterizing the evolution of the full microstructure over a large dpa range.

Phenotypic hip and elbow dysplasia trends in Rottweilers and Labrador retrievers in South Africa (2007-2015): Are we making progress?

PubMed

Kirberger, Robert M

2017-11-22

Canine hip and elbow dysplasia are major orthopaedic problems prevalent the world over, and South Africa is no exception. Hip and elbow dysplasia phenotypic status is certified by a number of different radiographic schemes in the world. South Africa uses the Fédération Cynologique Internationale system to certify hips, and the International Elbow Working Group scheme to certify elbows. One way of reducing these often crippling conditions is by selective breeding using only dogs with no or marginal dysplastic joints. In South Africa, only seven breeds, including the Rottweiler, have breeding restrictions for hip dysplasia. There are no such restrictions for elbow dysplasia. This study assessed the prevalence of hip and elbow dysplasia over a 9-year-period in the Rottweiler and the Labrador retriever in South Africa as evaluated by official national scrutineers. Records from 1148 Rottweilers and 909 Labrador retrievers were obtained and were graded as normal or dysplastic, and numerical values were also evaluated. Data were compared between the two breeds, males and females as well as over time and were compared with similar data of the Orthopaedic Foundation for Animals in the United States. The prevalence values for hip dysplasia in Rottweilers and Labrador retrievers were 22% and 31%, respectively, whereas for elbow dysplasia the values were 39% and 19%, respectively. In Labrador retrievers, this incidence was much higher than in the American population. Rottweiler hip and elbow dysplasia numerical scores significantly improved over time, whereas in Labrador retrievers, only hip dysplasia showed a minor but significant improvement. This study proved that prescribing minimum breeding requirements, as in the Rottweiler in this study, significantly improved the breeding stock, suggesting that minimum hip and elbow breeding requirements should be initiated for all breeds at risk of these often crippling conditions.

Functional outcomes of "floating elbow" injuries in adult patients.

PubMed

Yokoyama, K; Itoman, M; Kobayashi, A; Shindo, M; Futami, T

1998-05-01

To assess elbow function, complications, and problems of floating elbow fractures in adults receiving surgical treatment. Retrospective clinical review. Level I trauma center in Kanagawa, Japan. Fourteen patients with fifteen floating elbow injuries, excluding one immediate amputation, seen at the Kitasato University Hospital from January 1, 1984, to April 30, 1995. All fractures were managed surgically by various methods. In ten cases, the humeral and forearm fractures were treated simultaneously with immediate fixation. In three cases, both the humeral and forearm fractures were treated with delayed fixation on Day 1, 4, or 7. In the remaining two cases, the open forearm fracture was managed with immediate fixation and the humerus fracture with delayed fixation on Day 10 or 25. All subjects underwent standardized elbow evaluations, and results were compared with an elbow score based on a 100-point scale. The parameters evaluated were pain, motion, elbow and grip strength, and function during daily activities. Complications such as infections, nonunions, malunions, and refractures were investigated. Mean follow-up was forty-three months (range 13 to 112 months). At final follow-up, the mean elbow function score was 79 points, with 67 percent (ten of fifteen) of the subjects having good or excellent results. The functional outcome did not correlate with the Injury Severity Score of the individual patients, the existence of open injuries or neurovascular injuries, or the timing of surgery. There were one deep infection, two nonunions of the humerus, two nonunions of the forearm, one varus deformity of the humerus, and one forearm refracture. Based on the present data, we could not clarify the factors influencing the final functional outcome after floating elbow injury. These injuries, however, potentially have many complications, such as infection or nonunion, especially when there is associated brachial plexus injury. We consider that floating elbow injuries are severe injuries and that surgical stabilization is needed; beyond that, there are no specific forms of surgical treatment to reliably guarantee excellent results.

Current Concepts in Examination and Treatment of Elbow Tendon Injury

PubMed Central

Ellenbecker, Todd S.; Nirschl, Robert; Renstrom, Per

2013-01-01

Context: Injuries to the tendons of the elbow occur frequently in the overhead athlete, creating a significant loss of function and dilemma to sports medicine professionals. A detailed review of the anatomy, etiology, and pathophysiology of tendon injury coupled with comprehensive evaluation and treatment information is needed for clinicians to optimally design treatment programs for rehabilitation and prevention. Evidence Acquisitions: The PubMed database was searched in January 2012 for English-language articles pertaining to elbow tendon injury. Results: Detailed information on tendon pathophysiology was found along with incidence of elbow injury in overhead athletes. Several evidence-based reviews were identified, providing a thorough review of the recommended rehabilitation for elbow tendon injury. Conclusions: Humeral epicondylitis is an extra-articular tendon injury that is common in athletes subjected to repetitive upper extremity loading. Research is limited on the identification of treatment modalities that can reduce pain and restore function to the elbow. Eccentric exercise has been studied in several investigations and, when coupled with a complete upper extremity strengthening program, can produce positive results in patients with elbow tendon injury. Further research is needed in high-level study to delineate optimal treatment methods. PMID:24427389

[Post-traumatic arthritis in the young patient : Treatment options before the endoprosthesis].

PubMed

Burkhart, K J; Hollinger, B

2016-10-01

In the young patient, treatment of post-traumatic elbow arthritis remains difficult. Total elbow arthroplasty must be delayed for as long as possible. Therapy starts with nonoperative treatment. If this fails, operative options can be discussed. The aim of surgery is to provide a functional range of motion with acceptable pain without obstructing future treatment options. Patients with pain at terminal extension and/or flexion may benefit from arthroscopic or open debridement. Patients with advanced osteoarthritis and pain throughout the complete range of motion, who are too young for total elbow arthroplasty, are offered interposition arthroplasty or arthrodesis. Arthrodesis of the elbow leads to significant restrictions in daily life due to the complete loss of extension/flexion. Therefore, arthrodesis is only offered as treatment in exceptional circumstances. Interposition arthroplasty is a reasonable option for the young patient without significant bony defects, which may provide a stable, functional flexion arc with an acceptable pain level. Interposition arthroplasty preserves the revision options of re-interposition arthroplasty as well as the withdrawal to total elbow arthroplasty. Partial and total elbow arthroplasty are treatment options of elbow arthritis but are not subjects of this article.

Calcific periarthritis of the elbow presenting as acute tennis elbow.

PubMed

Jawad, F; Jawad, A S M

2014-01-01

A 28-year-old woman presented with sudden acute lateral epicondylitis. There was no history of preceding trauma or repetitive use of the arm. Because of the acute onset and signs of acute inflammation, an X-ray was arranged. The X-ray showed a hyperdense calcified elongated globule distal to the lateral epicondyle. A diagnosis of calcific periarthritis (calcium apatite) of the elbow was made. Calcific periarthritis has rarely been reported as a cause of acute elbow pain.

Traumatic elbow luxation in a free-ranging hedgehog (Erinaceus europaeus): surgical management using circumferential suture prostheses.

PubMed

Vallefuoco, Rosario; Pignon, Charly; Furst, Anna; Personne, Lauriane; Courreau, Jean-Francois; Moissonnier, Pierre

2013-06-01

A free-ranging adult female hedgehog (Erinaceus europaeus) was presented injured, presumably from vehicular trauma. Clinical and radiographic examination under general anesthesia revealed a lateral elbow luxation. Closed reduction was unsuccessful, so a surgical approach with circumferential suture prostheses was used to stabilize the elbow. Neither perioperative nor postoperative complications were recorded. The hedgehog regained good range of motion of the elbow and was fully able to run and to roll into a ball.

Elbow joint fatigue and bench-press training.

PubMed

Huang, Yen-Po; Chou, You-Li; Chen, Feng-Chun; Wang, Rong-Tyai; Huang, Ming-Jer; Chou, Paul Pei-Hsi

2014-01-01

Bench-press exercises are among the most common form of training exercise for the upper extremity because they yield a notable improvement in both muscle strength and muscle endurance. The literature contains various investigations into the effects of different bench-press positions on the degree of muscle activation. However, the effects of fatigue on the muscular performance and kinetics of the elbow joint are not understood fully. To investigate the effects of fatigue on the kinetics and myodynamic performance of the elbow joint in bench-press training. Controlled laboratory study. Motion research laboratory. A total of 18 physically healthy male students (age = 19.6 ± 0.8 years, height = 168.7 ± 5.5 cm, mass = 69.6 ± 8.6 kg) participated in the investigation. All participants were right-hand dominant, and none had a history of upper extremity injuries or disorders. Participants performed bench-press training until fatigued. Maximal possible number of repetitions, cycle time, myodynamic decline rate, elbow-joint force, and elbow-joint moment. We observed a difference in cycle time in the initial (2.1 ± 0.42 seconds) and fatigue (2.58 ± 0.46 seconds) stages of the bench-press exercise (P = .04). As the participants fatigued, we observed an increase in the medial-lateral force (P = .03) and internal-external moment (P ≤ .04) acting on the elbow joint. Moreover, a reduction in the elbow muscle strength was observed in the elbow extension-flexion (P ≤ .003) and forearm supination-pronation (P ≤ .001) conditions. The results suggest that performing bench-press exercises to the point of fatigue increases elbow-joint loading and may further increase the risk of injury. Therefore, when clinicians design bench-press exercise regimens for general athletic training, muscle strengthening, or physical rehabilitation, they should control carefully the maximal number of repetitions.

Comparison of short- to medium-term results of Coonrad-Morrey elbow replacement in patients with rheumatoid arthritis versus patients after elbow injuries

PubMed Central

Szyluk, Karol; Widuchowski, Wojciech; Jasiński, Andrzej; Koczy, Bogdan; Widuchowski, Jerzy

2013-01-01

Background The aim of this study was to assess the utility of the Coonrad-Morrey elbow prosthesis in patients with severe elbow dysfunction secondary to rheumatoid arthritis (RA) or post-traumatic elbow dysfunction. Material/Methods The study involved 35 patients followed up for a mean of 36 months. The patients were divided into those with RA (Group I) and those with post-traumatic elbow dysfunction (Group II). Treatment outcomes were evaluated according to the Mayo Elbow Performance Score (MEPS) and the Disabilities of the Arm, Shoulder and Hand Score (Quick DASH). Results According to the MEPS, there were 20 (57.15%) excellent, 12 (34.3%) good, 1 (2.85%) fair, and 2 (5.7%) poor outcomes. The mean post-operative Quick-DASH score for the entire study group was 37.73 points. In subgroup analysis, the MEPS-based evaluation revealed: 14 (70%) excellent, 5 (25%) good, and 1 (5%) satisfactory outcome in Group I, versus 6 (40%) excellent, 7 (46.7%) good, and 2 (13.3%) poor outcomes in Group II. The mean Quick Dash scores were 78.64 points in Group I and 76.36 points in Group II. The final MEPS scores in Group I (p=0.000018) and Group II (p=0.00065) were most markedly influenced by reduction in elbow pain and improvement in the ability to perform activities of daily living (ADL): p=0.000018 in Group I and p=0.000713 in Group II. Conclusions The treatment outcomes confirm the utility of arthroplasty for severe elbow dysfunctions; they were most strongly influenced by pain reduction and improved ability to perform activities of daily living. PMID:23291737

Arthroscopically assisted elbow interposition arthroplasty without hinged external fixation: surgical technique and patient outcomes.

PubMed

Chauhan, Aakash; Palmer, Bradley A; Baratz, Mark E

2015-06-01

Total elbow arthroplasty is successful in older, lower demand patients but not in the younger, more active individual with severe elbow arthritis. Interposition arthroplasty is an alternative for younger patients who hope to minimize the degree to which arm use is restricted. Interposition arthroplasty traditionally involves release of all ligaments and capsule. As a result, the postoperative care included the use of a hinged external fixator of the elbow to apply distraction and to permit motion during the early phases of healing. We describe a novel surgical technique without a hinged external fixator that allows secure fixation of the interposition graft through arthroscopic assistance and maintains the integrity of the medial collateral ligament with only a takedown and repair of the lateral collateral ligament complex. A retrospective chart review was performed to analyze 4 patients with an average age of 57 years who underwent surgery between 2007 and 2011. The patients were also contacted to assess elbow-specific American Shoulder and Elbow Surgeons and Disabilities of the Arm, Shoulder, and Hand scores. The average follow-up was 3.6 years (range, 2.5-6 years), and 1 patient was converted to a total elbow arthroplasty after 2.5 years because of persistent pain. The remaining 3 patients have done well with regard to pain control, stability, and functional use of the operative extremity. There were no postoperative complications. On the basis of our small series of patients, an arthroscopically assisted elbow interposition arthroplasty without hinged external fixation can provide satisfactory medium-term outcomes as a salvage procedure for a difficult condition with limited options. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Biomechanical influence of pin placement and elbow angle on joint distraction and hinge alignment for an arthrodiatasis elbow-pin-fixator construct.

PubMed

Lee, Wei-Shiun; Linz, Shang-Chih; Shih, Kao-Shang; Chao, Ching-Kong; Chen, Yeung-Jen; Fan, Chang-Yuan

2012-10-01

Stiffness and contracture of the periarticular tissues are common complications of a post-traumatic elbow. Arthrodiatasis is a surgical technique that uses an external fixator for initial immobilization and subsequent distraction. The two prerequisites for an ideal arthrodiatasis are concentric distraction (avoiding bony contact) and hinge alignment (reducing internal stress). This study used the finite element (FE) method to clarify the relationship between these two prerequisites and the initial conditions (pin placement, elbow angle, and distraction mode). A total of 12 variations of the initial conditions were symmetrically arranged to evaluate their biomechanical influence on concentric distraction and hinge alignment. The humeroulnar surface was hypothesized to be ideally distracted orthogonal to the line joining the tips of the olecranon and the coronoid. The eccentric separation of the humeroulnar surfaces is a response to the non-orthogonality of the distracting force and joining line. Pin placement significantly affects the effective moment arm of the fixing pins to distract the bridged elbow. Both elbow angle and distraction mode directly alter the direction of the distracting force at the elbow center. In general, the hinges misalignment occurs in a direction opposite to the distraction-activated site. After joint distraction, the elastic deflection of the fixing pins inevitably makes both elbow and fixator hinges to misalign. This indicates that both joint distraction and hinge alignment are the interactive mechanisms. The humeroulnar separation is more concentric in the situation of the 120 degrees humeral distraction by using stiffer pins with convergent placement. Even so, the eccentric displacement of the elbow hinge is a crucial consideration in the initial placement of the guiding pin to compensate for hinge misalignment.

IMPACT OF GRAVITY LOADING ON POST-STROKE REACHING AND ITS RELATIONSHIP TO WEAKNESS

PubMed Central

Beer, Randall F.; Ellis, Michael D.; Holubar, Bradley G.; Dewald, Julius P.A.

2010-01-01

The ability to extend the elbow following stroke depends on the magnitude and direction of torques acting at the shoulder. The mechanisms underlying this link remain unclear. The purpose of this study was to evaluate whether the effects of shoulder loading on elbow function were related to weakness or its distribution in the paretic limb. Ten subjects with longstanding hemiparesis performed movements with the arm either passively supported against gravity by an air bearing, or by activation of shoulder muscles. Isometric maximum voluntary torques at the elbow and shoulder were measured using a load cell. The speed and range of elbow extension movements were negatively impacted by actively supporting the paretic limb against gravity. However, the effects of gravity loading were not related to proximal weakness or abnormalities in the elbow flexor–extensor strength balance. The findings support the existence of abnormal descending motor commands that constrain the ability of stroke survivors to generate elbow extension torque in combination with abduction torque at the shoulder. PMID:17486581

Impact of gravity loading on post-stroke reaching and its relationship to weakness.

PubMed

Beer, Randall F; Ellis, Michael D; Holubar, Bradley G; Dewald, Julius P A

2007-08-01

The ability to extend the elbow following stroke depends on the magnitude and direction of torques acting at the shoulder. The mechanisms underlying this link remain unclear. The purpose of this study was to evaluate whether the effects of shoulder loading on elbow function were related to weakness or its distribution in the paretic limb. Ten subjects with longstanding hemiparesis performed movements with the arm either passively supported against gravity by an air bearing, or by activation of shoulder muscles. Isometric maximum voluntary torques at the elbow and shoulder were measured using a load cell. The speed and range of elbow extension movements were negatively impacted by actively supporting the paretic limb against gravity. However, the effects of gravity loading were not related to proximal weakness or abnormalities in the elbow flexor-extensor strength balance. The findings support the existence of abnormal descending motor commands that constrain the ability of stroke survivors to generate elbow extension torque in combination with abduction torque at the shoulder.

Effect of strength training on regional hypertrophy of the elbow flexor muscles.

PubMed

Drummond, Marcos D M; Szmuchrowski, Leszek A; Goulart, Karine N O; Couto, Bruno P

2016-10-01

Muscle hypertrophy is the main structural adaptation to strength training. We investigated the chronic effects of strength training on muscle hypertrophy in different regions of the elbow flexor muscles. Eleven untrained men (21.8 ± 1.62 years) underwent magnetic resonance imaging to determine the proximal, medial, distal, and mean cross-sectional areas (CSA) of the elbow flexors. The volunteers completed 12 weeks of strength training. The training protocol consisted of 4 sets of 8-10 maximum repetitions of unilateral elbow flexion. The interval between sets was 120 s. The training frequency was 3 sessions per week. The magnetic resonance images verified the presence of significant and similar hypertrophy in the distal, medial, and proximal portions of the elbow flexor muscles. Muscle hypertrophy may be assessed using only the medial CSA. We should not expect different degrees of hypertrophy among the regions of the elbow flexor muscles. Muscle Nerve 54: 750-755, 2016. © 2016 Wiley Periodicals, Inc.

sEMG feature evaluation for identification of elbow angle resolution in graded arm movement.

PubMed

Castro, Maria Claudia F; Colombini, Esther L; Aquino, Plinio T; Arjunan, Sridhar P; Kumar, Dinesh K

2014-11-25

Automatic and accurate identification of elbow angle from surface electromyogram (sEMG) is essential for myoelectric controlled upper limb exoskeleton systems. This requires appropriate selection of sEMG features, and identifying the limitations of such a system.This study has demonstrated that it is possible to identify three discrete positions of the elbow; full extension, right angle, and mid-way point, with window size of only 200 milliseconds. It was seen that while most features were suitable for this purpose, Power Spectral Density Averages (PSD-Av) performed best. The system correctly classified the sEMG against the elbow angle for 100% cases when only two discrete positions (full extension and elbow at right angle) were considered, while correct classification was 89% when there were three discrete positions. However, sEMG was unable to accurately determine the elbow position when five discrete angles were considered. It was also observed that there was no difference for extension or flexion phases.

Evaluation of a collagenase generated osteoarthritis biomarker in the synovial fluid from elbow joints of dogs with medial coronoid disease and unaffected dogs.

PubMed

Prink, Adam; Hayashi, Kei; Kim, Sun-Young; Kim, James; Kapatkin, Amy

2010-01-01

To evaluate whether synovial fluid concentrations of an osteoarthritis biomarker in dysplastic canine elbows with medial coronoid disease (MCD) are elevated compared with unaffected elbows and to determine if these concentrations correlate to the degree of articular cartilage damage. Cross sectional clinical study. Dogs (n=19; 35 elbows) with MCD and dogs (8; 16 elbows) with unaffected elbows. Concentrations of a collagenase-generated cleavage neoepitope of type II collagen (Col2-3/4C(long mono), or C2C) in joint fluid from elbows were analyzed and compared between dogs with MCD and unaffected dogs. Correlation of C2C concentration with subjective grading of articular cartilage surface damage was also evaluated. Mean (+/-SD) C2C concentration from MCD dogs was significantly higher (112.3+/-24.8 ng/mL) than in unaffected dogs (76.1+/-16.9 ng/mL; P<.05). There was a moderate correlation between cartilage damage grade and increasing C2C concentrations (P<.05, r=0.62) C2C concentrations are elevated in the synovial fluid of dogs with MCD compared with unaffected elbows, and a moderate, significant correlation was identified between these concentrations and subjective grading of articular cartilage damage. This preliminary data suggest that C2C concentrations in synovial fluid may have potential as a biomarker for diagnosis of articular cartilage damage associated with MCD and as a means of objectively determining the degree of articular cartilage damage.

Rhythmic Isometric Fatigue Patterns of the Elbow Flexors and Knee Extensors

ERIC Educational Resources Information Center

Ordway, George A.; And Others

1977-01-01

During a rhythmic, all-out task, the rates of fatigue experienced by elbow flexor and knee extendor muscle groups tend to differ, with the elbow flexors fatiguing more rapidly initially, but reaching a plateau at a relatively higher level than the knee extensors. (Author)

Shoulder disorders in an outpatient clinic: an epidemiological study.

PubMed

Malavolta, Eduardo Angeli; Gracitelli, Mauro Emilio Conforto; Assunção, Jorge Henrique; Pinto, Gustavo de Mello Ribeiro; da Silveira, Arthur Zorzi Freire; Ferreira, Arnaldo Amado

2017-01-01

To describe shoulder disorders in patients evaluated by two shoulder and elbow surgeons. This cross-sectional study analyzed patients evaluated by two authors, excluding acute fractures and dislocations and patients with symptoms not involving the shoulder. Age and sex distribution was determined for the different diagnoses. We evaluated 1001 patients. Mean age was 51.43±15.15 years and 51.0% were female. Disorders of the rotator cuff occurred in 64.3% (41.2% tendinopathy, 11.0% partial tears and 12.2% full-thickness tears). Adhesive capsulitis occurred in 13.5% of cases and glenohumeral instability in 8.1%. Rotator cuff disorders were more common in women, with a peak between 50 and 59 years for tendinopathy and partial tears and between 60 and 69 years for full-thickness tears. Glenohumeral instability was more frequent in men, with a peak between 30 and 39 years. The most frequent diagnosis was rotator cuff tendinopathy, followed by adhesive capsulitis, full-thickness rotator cuff tears, partial rotator cuff tears and glenohumeral instability. Rotator cuff lesions were more common in women, with a peak between 60 and 69 years for full-thickness tears. Level of Evidence IV, Case Series.

Allograft reconstruction after resection of malignant tumors of the scapula.

PubMed

Mnaymneh, Walid A; Temple, H Thomas; Malinin, Theodore I

2002-12-01

The oncologic and functional outcomes of six patients who had scapular allograft reconstruction after scapulectomy for malignant tumors were reviewed. Five patients had Stage IIB and one patient had Stage IB tumors. Total scapulectomy was done in five patients, and partial scapulectomy (glenoid and neck) was done in one patient. Frozen glycerolized scapular allografts were implanted and fixed with plates and screws. The scapular muscles were reattached to the allograft. Tendon reconstruction to replace the excised muscles was done in two patients. The patients were followed up for an average of 3.8 years (range, 2-6 years). Cosmesis, elbow, and hand function were good in all patients. There were no infections, nonunions, or shoulder dislocations. One patient fractured the body of the allograft after a fall. One patient had local recurrence and had scapulectomy 5 years postoperatively. Two patients died 3 and 5 years postoperatively with lung metastases but with functioning grafts. The mean functional result using the Musculoskeletal Tumor Society functional score was 82 (range, 77-87). In this series, scapular allograft reconstruction restored cosmesis, shoulder stability, and function. Preservation or reconstruction of rotator cuff muscles is recommended.

Analysis of combat sports players' injuries according to playing style for sports physiotherapy research.

PubMed

Noh, Ji-Woong; Park, Byoung-Sun; Kim, Mee-Young; Lee, Lim-Kyu; Yang, Seung-Min; Lee, Won-Deok; Shin, Yong-Sub; Kim, Ju-Hyun; Lee, Jeong-Uk; Kwak, Taek-Yong; Lee, Tae-Hyun; Kim, Ju-Young; Park, Jaehong; Kim, Junghwan

2015-08-01

[Purpose] This study describes the characteristics of injuries in strike and non-strike combat sports, and the results are intended for use in the area of sports physiotherapy research. [Subjects and Methods] The study was conducted on 159 athletes involved in a variety of combat sports. The participants included elite college players of the following sports: judo (47), ssireum (19), wrestling (13), kendo (30), boxing (16), and taekwondo (34). Of the participants, 133 were male and 26 were female. In the case of ssireum and boxing, all of the athletes were male. [Results] In the case of the combat sports, the types of injury and injured regions differed according to playing style. Dislocation and injuries to the neck, shoulders, and elbows were more frequent in the non-strike sports, while injuries to the wrists and hands were more frequent in the strike sports. There was a high incidence of sprains, strains, bruises, and injuries to the lower limbs in both groups. [Conclusion] We suggest that the characteristics of injuries in combat sports differ according to playing style, and our study will therefore provide physical therapists and researchers with information that can be used to prevent injury.

Analysis of combat sports players’ injuries according to playing style for sports physiotherapy research

PubMed Central

Noh, Ji-Woong; Park, Byoung-Sun; Kim, Mee-Young; Lee, Lim-Kyu; Yang, Seung-Min; Lee, Won-Deok; Shin, Yong-Sub; Kim, Ju-Hyun; Lee, Jeong-Uk; Kwak, Taek-Yong; Lee, Tae-Hyun; Kim, Ju-Young; Park, Jaehong; Kim, Junghwan

2015-01-01

[Purpose] This study describes the characteristics of injuries in strike and non-strike combat sports, and the results are intended for use in the area of sports physiotherapy research. [Subjects and Methods] The study was conducted on 159 athletes involved in a variety of combat sports. The participants included elite college players of the following sports: judo (47), ssireum (19), wrestling (13), kendo (30), boxing (16), and taekwondo (34). Of the participants, 133 were male and 26 were female. In the case of ssireum and boxing, all of the athletes were male. [Results] In the case of the combat sports, the types of injury and injured regions differed according to playing style. Dislocation and injuries to the neck, shoulders, and elbows were more frequent in the non-strike sports, while injuries to the wrists and hands were more frequent in the strike sports. There was a high incidence of sprains, strains, bruises, and injuries to the lower limbs in both groups. [Conclusion] We suggest that the characteristics of injuries in combat sports differ according to playing style, and our study will therefore provide physical therapists and researchers with information that can be used to prevent injury. PMID:26357420

Midterm results of osteochondral allograft transplantation to the humeral head.

PubMed

Riff, Andrew J; Yanke, Adam B; Shin, Jason J; Romeo, Anthony A; Cole, Brian J

2017-07-01

This study evaluated clinical outcomes of osteochondral allograft (OCA) transplantation for humeral head osteochondral defects. We hypothesized that patients with isolated humeral head disease would achieve favorable results and that patients with bipolar disease would experience inferior outcomes. We identified patients who underwent humeral head OCA transplantation. Subjective questionnaire data were obtained preoperatively and at a minimum of 2 years postoperatively. Radiographs were evaluated for graft incorporation. Failure was defined by conversion to shoulder arthroplasty, American Shoulder and Elbow Surgeons score <50, or dissatisfaction with the surgical result. Twenty patients (65% male) met inclusion criteria. Patients were an average age of 24.8 ± 8.1 years. Eleven patients underwent concomitant glenoid surgery (microfracture or meniscal allograft resurfacing). Follow-up was available for 18 patients (90%) at mean of 67 months. All grafts incorporated except 2. Four patients underwent shoulder arthroplasty at mean of 25 months postoperatively (all after pain pump chondrolysis). Eleven of the 20 patients were satisfied (all dissatisfied patients underwent glenoid surgery). Significant improvements (P < .001) were seen for the visual analog scale (from 6.1 to 1.5), Simple Shoulder Test (from 32 to 73), American Shoulder and Elbow Surgeons score (from 39 to 76), and the physical component of the 12-Item Short Form Survey (from 38 to 48). Pain pump patients who did not progress to arthroplasty experienced inferior satisfaction (40% vs. 87.5%, P = .04) and a trend toward inferior outcomes compared with the rest of the cohort. OCA transplantation is a viable option for young patients with isolated humeral chondral injury. Patients with bipolar disease or a history of intra-articular pain pump have increased failure and decreased subjective outcomes. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

[Modified osteotomy of olecranon for the management of inter-condylar fracture of the humerus].

PubMed

Mei, Zheng-Feng; Lei, Wen-Tao; Huang, Dong-Hui; Zhao, Qi-Hui; Qu, Hang-Bo; Ni, Lian-Zhi

2017-01-25

To explore the surgical method and clinical outcome of modified osteotomy of olecranon for the treatment of inter-condylar fracture of humerus. From May 2007 to December 2012, 32 patients of intercondylar fracture of humerus were treated surgically through the approach of modified osteotomy of olecranon. The patients were 21 males and 11 females with a mean age of 46.3 years (ranged 18 to 65 years). Nineteen fractures occurred on the right extremity and 13 on the left extremity. According to the AO classification, type C1 fracture was found in 7, C2 in 11 and C3 in 14. Five patients suffered from open fracture (Gustilo type Iin 3, type II in 2). Other fractures occurred in 6 patients and the primary injury of nerve occurred 6. The healing of the osteotomy was evaluated with physical examination and plain X-ray film, and the function of elbow was assessed according to Cassebaum scale. All the patients were followed from 9 months to 5 years(average, 1.9 years). All the osteotomies healed at 7.4 weeks averagely after operation, and no nonunion, delayed union, fracture of ulna olecranon were found. Two cases had little pain on the elbow, heterotopic ossification occurred in 2 cases and cutting bone block loosed in 1 case. The function of the elbow showed excellent in 19 cases, good in 8, fair in 4 and poor in 1. The use of the approach of modified olecranon osteotomy for surgical management of intercondylar fracture of humerus has some advantages, it provides satisfactory stability with simple technical procedures avoiding inter-articular invasion, and it facilitates rehabilitation exercises and providing good results with low complication rates.

Platelet-rich plasma in tendon-related disorders: results and indications.

PubMed

Filardo, Giuseppe; Di Matteo, Berardo; Kon, Elizaveta; Merli, Giulia; Marcacci, Maurilio

2016-09-24

Platelet-rich plasma (PRP) is currently the most exploited strategy in the clinical practice to provide a regenerative stimulus for tendon healing. The aim of the present study was to systematically review the available evidence on the treatment of the main tendon disorders where PRP is currently applied. A systematic review of the literature was performed on the use of PRP as a treatment for tendinopathies focusing on the following sites: Achilles tendon, patellar tendon, rotator cuff tendons, and lateral elbow tendons. The following inclusion criteria for relevant articles were used: clinical trials written in English language up to 21 June 2016 on the use of PRP in the conservative or surgical treatment of the aforementioned tendinopathies. The research identified the following clinical trials dealing with the application of PRP in the selected tendons: 19 papers on patellar tendon (6 being RCTs: 4 dealing with PRP conservative application and 2 surgical), 24 papers on Achilles tendon (4 RCTs: 3 conservative and 1 surgical), 29 on lateral elbow tendons (17 RCTs, all conservative), and 32 on rotator cuff (22 RCTs: 18 surgical and 3 conservative). Patellar tendons seem to benefit from PRP injections, whereas in the Achilles tendon, PRP application is not indicated neither as a conservative approach nor as a surgical augmentation. Lateral elbow tendinopathy showed an improvement in most of the high-level studies, but the lack of proven superiority with respect to the more simple whole-blood injections still questions its use in the clinical practice. With regard to rotator cuff pathology, the vast majority of surgical RCTs documented a lack of beneficial effects, whereas there is still inconclusive evidence concerning its conservative application in rotator cuff disorders. Systematic review of level I-IV trials, Level IV.

Concerns on Little League Elbow.

ERIC Educational Resources Information Center

Wells, Michael J.; Bell, Gerald W.

1995-01-01

Little league elbow is a common overuse injury resulting from repetitive valgus stress on the elbow during overhead throwing. Prevention and treatment should emphasize education of athletes, parents, and coaches about its etiology. The paper examines bone development, noting that the condition is highly treatable if diagnosed in early development.…

Elbow hemiarthroplasty for the management of distal humeral fractures: current technique, indications and results.

PubMed

Phadnis, Joideep; Watts, Adam C; Bain, Gregory I

2016-07-01

There has been a growing recent interest in the use of elbow hemiarthroplasty for the treatment of distal humeral trauma in select patients. However, the current available evidence regarding outcome after elbow hemiarthroplasty is limited to case series and biomechanical data. Consequently, the procedure remains unfamiliar to many surgeons. The aim of the present review is to outline the evidence regarding elbow hemiarthroplasty and to use this, along with the author's experience, to better describe the indications, surgical technique and outcomes after this procedure.

Elbow hemiarthroplasty for the management of distal humeral fractures: current technique, indications and results

PubMed Central

Watts, Adam C; Bain, Gregory I

2016-01-01

There has been a growing recent interest in the use of elbow hemiarthroplasty for the treatment of distal humeral trauma in select patients. However, the current available evidence regarding outcome after elbow hemiarthroplasty is limited to case series and biomechanical data. Consequently, the procedure remains unfamiliar to many surgeons. The aim of the present review is to outline the evidence regarding elbow hemiarthroplasty and to use this, along with the author’s experience, to better describe the indications, surgical technique and outcomes after this procedure. PMID:27583016

Soft tissue coverage of the elbow in a developing country.

PubMed

Pirela-Cruz, Miguel A; Reddy, Kartheek K; Higgs, Matthew

2007-09-01

Two cases that required soft tissue coverage to the anterior aspect of the elbow are presented. A fasciocutaneous intercostal perforator chest wall flap was used for one patient when only skin and fascia coverage was required. A latissimus dorsi myocutaneous flap was used to provide soft tissue coverage and supply motor power for elbow flexion after contracture release in the other. The surgical techniques for each of these flaps are discussed in the context of addressing soft tissue traumatic injuries about the elbow in a developing country with limited resources.

Effect of Reynolds number on flow and mass transfer characteristics of a 90 degree elbow

NASA Astrophysics Data System (ADS)

Fujisawa, Nobuyuki; Ikarashi, Yuya; Yamagata, Takayuki; Taguchi, Syoichi

2016-11-01

The flow and mass transfer characteristics of a 90 degree elbow was studied experimentally by using the mass transfer measurement by plaster dissolution method, the surface flow visualization by oil film method and stereo PIV measurement. The experiments are carried out in a water tunnel of a circular pipe of 56mm in diameter with a working fluid of water. The Reynolds number was varied from 30000 to 200000. The experimental result indicated the change of the mass transfer coefficient distribution in the elbow with increasing the Reynolds number. This phenomenon is further examined by the surface flow visualization and measurement of secondary flow pattern in the elbow, and the results showed the suggested change of the secondary flow pattern in the elbow with increasing the Reynolds numbers.

Muscle contributions to elbow joint rotational stiffness in preparation for sudden external arm perturbations.

PubMed

Holmes, Michael W R; Keir, Peter J

2014-04-01

Understanding joint stiffness and stability is beneficial for assessing injury risk. The purpose of this study was to examine joint rotational stiffness for individual muscles contributing to elbow joint stability. Fifteen male participants maintained combinations of three body orientations (standing, supine, sitting) and three hand preloads (no load, solid tube, fluid filled tube) while a device imposed a sudden elbow extension. Elbow angle and activity from nine muscles were inputs to a biomechanical model to determine relative contributions to elbow joint rotational stiffness, reported as percent of total stiffness. A body orientation by preload interaction was evident for most muscles (P<.001). Brachioradialis had the largest change in contribution while standing (no load, 18.5%; solid, 23.8%; fluid, 26.3%). Across trials, the greatest contributions were brachialis (30.4±1.9%) and brachioradialis (21.7±2.2%). Contributions from the forearm muscles and triceps were 5.5±0.6% and 9.2±1.9%, respectively. Contributions increased at time points closer to the perturbation (baseline to anticipatory), indicating increased neuromuscular response to resist rotation. This study quantified muscle contributions that resist elbow perturbations, found that forearm muscles contribute marginally and showed that orientation and preload should be considered when evaluating elbow joint stiffness and safety.

Anatomic factors related to the cause of tennis elbow.

PubMed

Bunata, Robert E; Brown, David S; Capelo, Roderick

2007-09-01

The pathogenesis of lateral epicondylitis remains unclear. Our purpose was to study the anatomy of the lateral aspect of the elbow under static and dynamic conditions in order to identify bone-to-tendon and tendon-to-tendon contact or rubbing that might cause abrasion of the tissues. Eighty-five cadaveric elbows were examined to determine details related to the bone structure and musculotendinous origins. We identified the relative positions of the musculotendinous units and the underlying bone when the elbow was in different degrees of flexion. We also recorded the contact between the extensor carpi radialis brevis and the lateral edge of the capitellum as elbow motion occurred, and we sought to identify the areas of the capitellum and extensor carpi radialis brevis where contact occurs. The average site of origin of the extensor carpi radialis brevis on the humerus lay slightly medial and superior to the outer edge of the capitellum. As the elbow was extended, the undersurface of the extensor carpi radialis brevis rubbed against the lateral edge of the capitellum while the extensor carpi radialis longus compressed the brevis against the underlying bone. The extensor carpi radialis brevis tendon has a unique anatomic location that makes its undersurface vulnerable to contact and abrasion against the lateral edge of the capitellum during elbow motion.

Tennis elbow: associated psychological factors.

PubMed

Aben, Aurelie; De Wilde, Lieven; Hollevoet, Nadine; Henriquez, Carlos; Vandeweerdt, Marc; Ponnet, Koen; Van Tongel, Alexander

2018-03-01

The etiology of tennis elbow is multifactorial. Overuse of the wrist extensors along with anatomic factors, such as flexibility problems, aging, and poor blood circulation, may play a role. This study investigated whether patients with tennis elbow have a different psychological profile compared with healthy controls. Patients with clinical signs of tennis elbow, consulting at the Ghent University Hospital between September 2015 and January 2017, were offered a paper-and-pencil questionnaire about Big Five personality traits, perfectionism, anxiety, depression, work satisfaction, and working conditions. Healthy controls in the same risk group were offered the same questionnaires. We recruited 69 patients (35 men, 34 women) and 100 controls (44 men, 56 women). Tennis elbow patients scored significantly lower on the personality traits extraversion and agreeableness. Men, in particular, scored significantly higher on perfectionism and were more likely to develop an anxiety disorder or a depression. Concerning work, patients indicated a significantly higher workload (especially men) and a significantly lower autonomy (especially women). Female patients also indicated less contact with colleagues. However, work satisfaction was relatively high in both groups. The results suggest that there is a relationship between complaints related to tennis elbow and psychological characteristics. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

The effect of elbow flexor fatigue on spine kinematics and muscle activation in response to sudden loading at the hands.

PubMed

Zwambag, Derek P; Freeman, Nikole E; Brown, Stephen H M

2015-04-01

Sudden loads, originating at either the hands or the feet, can cause injury to spine structures. As muscles are primarily responsible for stabilization following a perturbation, the effect of spine muscle fatigue in this context has been well investigated. However, the effect of fatigue of arm muscles, which can help control perturbations originating at the hands, on the spine is unknown. The purpose of this study was to determine if the magnitude of spine flexion or the pre-activation, reflex amplitude, and reflex latency of spine muscles were altered by elbow flexor fatigue during a sudden loading (6.8 kg) perturbation at the hands. Elbow flexor fatigue was induced by an isometric 30% maximal elbow flexion moment until failure. Results demonstrate that spine kinematics were not altered in the presence of elbow flexor fatigue. Small magnitude differences in trunk muscle pre- and peak activation indicate that the presence of elbow flexor fatigue does not necessitate substantially greater spine muscle action under the tested conditions. Despite fatigued elbow flexors, the arm muscles were sufficiently able to control the perturbation. Interestingly, 5/14 participants demonstrated altered reflex latencies in all observed muscles that lasted up to 10 min after the fatiguing task. Copyright © 2015 Elsevier Ltd. All rights reserved.

Serial casting for elbow flexion contractures in neonatal brachial plexus palsy.

PubMed

Duijnisveld, B J; Steenbeek, D; Nelissen, R G H H

2016-09-02

The objective of this study was to evaluate the effectiveness of serial casting of elbow flexion contractures in neonatal brachial plexus palsy. A prospective consecutive cohort study was performed with a median follow-up of 5 years. Forty-one patients with elbow flexion contractures ≥ 30° were treated with serial casting until the contracture was ≤ 10°, for a maximum of 8 weeks. Range of motion, number of recurrences and patient satisfaction were recorded and analyzed using Wilcoxon signed-rank and Cox regression tests. Passive extension increased from a median of -40° (IQR -50 to -30) to -15° (IQR -10 to -20, p < 0.001). Twenty patients showed 37 recurrences. The baseline severity of passive elbow extension had a hazard ratio of 0.93 (95% CI 0.89 to 0.96, p < 0.001) for first recurrence. Median patient satisfaction was moderate. Four patients showed loss of flexion mobility and in two patients serial casting had to be prematurely replaced by night splinting due to complaints. Serial casting improved elbow flexion contractures, although recurrences were frequent. The severity of elbow flexion contracture is a predictor of recurrence. We recommend more research on muscle degeneration and determinants involved in elbow flexion contractures to improve treatment strategies and prevent side-effects.

ANALYSIS OF THE PATTERN AND MECHANISM OF ELBOW INJURIES RELATED TO ARMBAR-TYPE ARMLOCKS IN JIU-JITSU FIGHTERS.

PubMed

Almeida, Thiago Bernardo Carvalho DE; Dobashi, Eiffel Tsuyoshi; Nishimi, Alexandre Yukio; Almeida, Eduardo Bernardo DE; Pascarelli, Luciano; Rodrigues, Luciano Miller Reis

2017-01-01

The objective of this study was to analyze elbow injuries and their probable mechanism in Jiu-Jitsu fighters resulting from the armbar-type armlock. We evaluated 5 high-performance Jiu-Jitsu fighters from the Gracie Elite gym who were injured during a tournament. All were healthy males with a mean age of 28.8 years. The right arm was involved in three patients (60%). The athletes were followed for approximately 4.6 months, and pain was present in all cases. Clinical examination of the elbow was performed immediately after the injury and when magnetic resonance imaging (MRI) was performed. The radiography showed no changes. Clinical examination detected specific tender points on the medial and anterior topography of the elbows, but no ligamentous instability of the elbow was seen during dynamic testing. The main MRI findings were injury to the common flexor tendon and the ulnar collateral ligament, bone contusion of the distal humerus and olecranon, and joint effusion. The main pattern of injury indicated by the MRI in the athletes was injury to the medial elbow complex. The primary mechanism that determined the injury was most likely elbow hyperextension applied with the forearm in neutral position of forearm. Level of Evidence IV, Case Series.

ANALYSIS OF THE PATTERN AND MECHANISM OF ELBOW INJURIES RELATED TO ARMBAR-TYPE ARMLOCKS IN JIU-JITSU FIGHTERS

PubMed Central

ALMEIDA, THIAGO BERNARDO CARVALHO DE; DOBASHI, EIFFEL TSUYOSHI; NISHIMI, ALEXANDRE YUKIO; ALMEIDA, EDUARDO BERNARDO DE; PASCARELLI, LUCIANO; RODRIGUES, LUCIANO MILLER REIS

2017-01-01

ABSTRACT Objective: The objective of this study was to analyze elbow injuries and their probable mechanism in Jiu-Jitsu fighters resulting from the armbar-type armlock. Methods: We evaluated 5 high-performance Jiu-Jitsu fighters from the Gracie Elite gym who were injured during a tournament. All were healthy males with a mean age of 28.8 years. The right arm was involved in three patients (60%). The athletes were followed for approximately 4.6 months, and pain was present in all cases. Clinical examination of the elbow was performed immediately after the injury and when magnetic resonance imaging (MRI) was performed. The radiography showed no changes. Clinical examination detected specific tender points on the medial and anterior topography of the elbows, but no ligamentous instability of the elbow was seen during dynamic testing. Results: The main MRI findings were injury to the common flexor tendon and the ulnar collateral ligament, bone contusion of the distal humerus and olecranon, and joint effusion. Conclusion: The main pattern of injury indicated by the MRI in the athletes was injury to the medial elbow complex. The primary mechanism that determined the injury was most likely elbow hyperextension applied with the forearm in neutral position of forearm. Level of Evidence IV, Case Series. PMID:29081707

Arthroscopic Fragment Resection for Capitellar Osteochondritis Dissecans in Adolescent Athletes: 5- to 12-Year Follow-up

PubMed Central

Ueda, Yusuke; Sugaya, Hiroyuki; Takahashi, Norimasa; Matsuki, Keisuke; Tokai, Morihito; Onishi, Kazutomo; Hoshika, Shota; Hamada, Hiroshige

2017-01-01

Background: Capitellar osteochondritis dissecans (OCD) in skeletally immature athletes has often been seen in baseball players and gymnasts. The choice of surgical procedure for unstable lesions in skeletally immature athletes remains controversial. Purpose: To investigate functional outcomes and radiographic changes in the midterm to long-term postoperative period after arthroscopic (AS) resection for small to large capitellar OCD lesions in skeletally immature athletes. Study Design: Case series; Level of evidence, 4. Methods: A total of 38 elbows in 38 patients (33 boys, 5 girls; mean age, 14 years [range, 13-15 years]) with skeletally immature elbows underwent AS resection for capitellar OCD. Patients were observed for at least 5 years (mean, 8 years [range, 5-12 years]). Elbows with a lesion width that did not exceed one-half of the radial head diameter were assigned to group 1 (n = 17 elbows), and larger lesions were assigned to group 2 (n = 21 elbows). Functional scores, patient satisfaction, range of motion (ROM), and osteoarthritis (OA) grades were evaluated between the groups. Results: All patients returned to sports activity. Functional scores at the final follow-up were not significantly different between the groups. Patient satisfaction scores were significantly higher in group 1 than in group 2. There was significant improvement in flexion ROM at the final follow-up compared with preoperative values in group 1 (P = .017), and there was a significant between-group difference (group 1: 141°; group 2: 133°; P = .002). Extension ROM showed significant improvement in both groups (group 1: from –8° to 3°; group 2: from –17° to –1°; P < .001 for both). Group 1 tended to have better extension than group 2, but the difference was not significant. There were no elbows with severe OA in either group, but the OA grade progressed in 5 elbows (29%) in group 1 and 9 elbows (43%) in group 2, and this rate of OA progression was statistically significant between groups (P = .005). Conclusion: Both functional outcomes and radiological findings after AS fragment resection were excellent in elbows with small lesions. Although overall outcomes were acceptable in elbows with larger lesions, flexion ROM and patient satisfaction scores were significantly inferior to those in elbows with smaller lesions. PMID:29276715

Quantifying the errors due to the superposition of analytical deformation sources

NASA Astrophysics Data System (ADS)

Neuberg, J. W.; Pascal, K.

2012-04-01

The displacement field due to magma movement in the subsurface is often modelled using a Mogi point source or a dislocation Okada source embedded in a homogeneous elastic half-space. When the magmatic system cannot be modelled by a single source it is often represented by several sources, their respective deformation fields are superimposed. However, in such a case the assumption of homogeneity in the half-space is violated and the interaction between sources in an elastic medium is neglected. In this investigation we have quantified the effects of neglecting the interaction between sources on the surface deformation field. To do so, we calculated the vertical and horizontal displacements for models with adjacent sources and we tested them against the solutions of corresponding numerical 3D finite element models. We implemented several models combining spherical pressure sources and dislocation sources, varying the pressure or dislocation of the sources and their relative position. We also investigated three numerical methods to model a dike as a dislocation tensile source or as a pressurized tabular crack. We found that the discrepancies between simple superposition of the displacement field and a fully interacting numerical solution depend mostly on the source types and on their spacing. The errors induced when neglecting the source interaction are expected to vary greatly with the physical and geometrical parameters of the model. We demonstrated that for certain scenarios these discrepancies can be neglected (<5%) when the sources are separated by at least 4 radii for two combined Mogi sources and by at least 3 radii for juxtaposed Mogi and Okada sources

The hematoma block: a simple, effective technique for closed reduction of ankle fracture dislocations.

PubMed

Ross, Adrianne; Catanzariti, Alan R; Mendicino, Robert W

2011-01-01

Management of a dislocated ankle fracture can be challenging because of instability of the ankle mortise, a compromised soft tissue envelope, and the potential neurovascular compromise. Every effort should be made to quickly and efficiently relocate the disrupted ankle joint. Within the emergency department setting, narcotics and benzodiazepines can be used to sedate the patient before attempting closed reduction. The combination of narcotics and benzodiazepines provides relief of pain and muscle guarding; however, it conveys a risk of seizure as well as respiratory arrest. An alternative to conscious sedation is the hematoma block, or an intra-articular local anesthetic injection in the ankle joint and the associated fracture hematoma. The hematoma block offers a comparable amount of analgesia to conscious sedation without the additional cardiovascular risk, hospital cost, and procedure time. Copyright © 2011 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Limits on passivating defects in semiconductors: the case of Si edge dislocations.

PubMed

Chan, Tzu-Liang; West, D; Zhang, S B

2011-07-15

By minimizing the free energy while constraining dopant density, we derive a universal curve that relates the formation energy (E(form)) of doping and the efficiency of defect passivation in terms of segregation of dopants at defect sites. The universal curve takes the simple form of a Fermi-Dirac distribution. Our imposed constraint defines a chemical potential that assumes the role of "Fermi energy," which sets the thermodynamic limit on the E(form) required to overcome the effect of entropy such that dopant segregation at defects in semiconductors can occur. Using Si edge dislocation as an example, we show by first-principles calculations how to map the experimentally measurable passivation efficiency to our calculated E(form) by using the universal curve for typical n- and p-type substitutional dopants. We show that n-type dopants are ineffective. Among p-type dopants, B can satisfy the thermodynamic limit while improving electronic properties.

Phenomenological model for transient deformation based on state variables

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jackson, M S; Cho, C W; Alexopoulos, P

The state variable theory of Hart, while providing a unified description of plasticity-dominated deformation, exhibits deficiencies when it is applied to transient deformation phenomena at stresses below yield. It appears that the description of stored anelastic strain is oversimplified. Consideration of a simple physical picture based on continuum dislocation pileups suggests that the neglect of weak barriers to dislocation motion is the source of these inadequacies. An appropriately modified description incorporating such barriers then allows the construction of a macroscopic model including transient effects. Although the flow relations for the microplastic element required in the new theory are not known,more » tentative assignments may be made for such functions. The model then exhibits qualitatively correct behavior when tensile, loading-unloading, reverse loading, and load relaxation tests are simulated. Experimental procedures are described for determining the unknown parameters and functions in the new model.« less

Decreased Shoulder External Rotation and Flexion Are Greater Predictors of Injury Than Internal Rotation Deficits: Analysis of 132 Pitcher-Seasons in Professional Baseball.

PubMed

Camp, Christopher L; Zajac, John M; Pearson, David B; Sinatro, Alec M; Spiker, Andrea M; Werner, Brian C; Altchek, David W; Coleman, Struan H; Dines, Joshua S

2017-09-01

The primary aims of this work were to (1) describe normal range of motion (ROM) profiles for elite pitchers, (2) describe the characteristics of shoulder and elbow injuries in professional pitchers over a 6-year period in one Major League Baseball organization, and (3) identify ROM measures that were independently associated with a future shoulder or elbow injury. Over 6 seasons (2010-2015), a preseason assessment was performed on all pitchers invited to Major League Baseball Spring Training for a single organization. ROM measures included shoulder flexion, horizontal adduction, external rotation (ER), internal rotation, as well as elbow flexion and extension, were measured for both the dominant and nondominant arm, and total range of motion and deficits were calculated. All noncontact shoulder and elbow injuries were identified. Using multivariate binomial logistic regression analysis to control for age, height, weight, and all other ROM measures, the factors associated with an increased risk of subsequent shoulder or elbow injury were identified. A total of 53 shoulder (n = 25) and elbow (n = 28) injuries occurred during 132 pitcher seasons (n = 81 pitchers). The most significant categorical risk factor associated with increased elbow injury rates was the presence of a shoulder flexion deficit >5° (odds ratio [OR] 2.83; P = .042). For continuous variables, the risk of elbow injury increased by 7% for each degree of increased shoulder ER deficit (OR 1.07; P = .030) and 9% for each degree of decreased shoulder flexion (OR 1.09; P = .017). None of the measures significantly correlated with shoulder injuries. Preseason shoulder ER and flexion deficits are independent risk factors for the development of elbow injuries during the upcoming season. Although prior work has supported the importance of reducing glenohumeral internal rotation deficits in pitchers, this study demonstrates that deficits in shoulder ER and flexion are more significant predictors of subsequent elbow injury. Level III, retrospective comparative study. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Ulnar neuropathy and medial elbow pain in women's fastpitch softball pitchers: a report of 6 cases.

PubMed

Smith, Adam M; Butler, Thomas H; Dolan, Michael S

2017-12-01

Elite-level women's fastpitch softball players place substantial biomechanical strains on the elbow that can result in medial elbow pain and ulnar neuropathic symptoms. There is scant literature reporting the expected outcomes of the treatment of these injuries. This study examined the results of treatment in a series of these patients. We identified 6 female softball pitchers (4 high school and 2 collegiate) with medial elbow pain and ulnar neuropathic symptoms. Trials of conservative care failed in all 6, and they underwent surgical treatment with subcutaneous ulnar nerve transposition. These patients were subsequently monitored postoperatively to determine outcome. All 6 female pitchers had early resolution of elbow pain and neuropathic symptoms after surgical treatment. Long-term follow-up demonstrated that 1 patient quit playing softball because of other injuries but no longer reported elbow pain or paresthesias. One player was able to return to pitching at the high school level but had recurrent forearm pain and neuritis 1 year later while playing a different sport and subsequently stopped playing competitive sports. Four patients continued to play at the collegiate level without further symptoms. Medial elbow pain in women's softball pitchers caused by ulnar neuropathy can be treated effectively with subcutaneous ulnar nerve transposition if nonsurgical options fail. Further study is necessary to examine the role of overuse, proper training techniques, and whether pitching limits may be necessary to avoid these injuries. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Direct Coaptation of the Phrenic Nerve With the Posterior Division of the Lower Trunk to Restore Finger and Elbow Extension Function in Patients With Total Brachial Plexus Injuries.

PubMed

Wang, Shu-feng; Li, Peng-cheng; Xue, Yun-hao; Zou, Ji-yao; Li, Wen-jun; Li, Yucheng

2016-02-01

To overcome the mismatch in nerve sizes in phrenic nerve transfer to the radial nerve for elbow and finger extension reanimation for patients with total brachial plexus injuries (TBPI), a selective neurotization procedure was designed. To investigate the long-term results of phrenic nerve transfer to the posterior division of the lower trunk with direct coaptation in restoring elbow and finger extension after TBPI. Phrenic nerve was transferred to and directly coapted with the posterior division of the lower trunk in 27 patients with TBPI. Seven patients were <18 years old (adolescent group), and the remaining 20 patients ≥18 years (adult group). Postoperative mean follow-up period was 54 ± 9 months (range, 48-85 months). The motor function attained M3 or greater in 81.5% of patients for elbow extension and in 48% of patients for finger extension. The percentage of patients who regained M3 or greater muscle power of finger extension in the adolescent group and the adult group was 71.4%, and 40%, respectively. Meanwhile, 85.7% in the adolescent group and 80% in the adult group achieved M3 or greater muscle power of elbow extension. There were no significant differences between the 2 groups. The elbow extension and finger extension were synchronous contractions and did not become independent of respiratory effort. This procedure simultaneously and effectively restores the function of elbow and finger extension in patients after TBPI. However, the patients could not do elbow and finger extension separately.

Limb position sense, proprioceptive drift and muscle thixotropy at the human elbow joint

PubMed Central

Tsay, A; Savage, G; Allen, T J; Proske, U

2014-01-01

These experiments on the human forearm are based on the hypothesis that drift in the perceived position of a limb over time can be explained by receptor adaptation. Limb position sense was measured in 39 blindfolded subjects using a forearm-matching task. A property of muscle, its thixotropy, a contraction history-dependent passive stiffness, was exploited to place muscle receptors of elbow muscles in a defined state. After the arm had been held flexed and elbow flexors contracted, we observed time-dependent changes in the perceived position of the reference arm by an average of 2.8° in the direction of elbow flexion over 30 s (Experiment 1). The direction of the drift reversed after the arm had been extended and elbow extensors contracted, with a mean shift of 3.5° over 30 s in the direction of elbow extension (Experiment 2). The time-dependent changes could be abolished by conditioning elbow flexors and extensors in the reference arm at the test angle, although this led to large position errors during matching (±10°), depending on how the indicator arm had been conditioned (Experiments 3 and 4). When slack was introduced in the elbow muscles of both arms, by shortening muscles after the conditioning contraction, matching errors became small and there was no drift in position sense (Experiments 5 and 6). These experiments argue for a receptor-based mechanism for proprioceptive drift and suggest that to align the two forearms, the brain monitors the difference between the afferent signals from the two arms. PMID:24665096

Effect of Obesity on Complication Rate After Elbow Arthroscopy in a Medicare Population.

PubMed

Werner, Brian C; Fashandi, Ahmad H; Chhabra, A Bobby; Deal, D Nicole

2016-03-01

To use a national insurance database to explore the association of obesity with the incidence of complications after elbow arthroscopy in a Medicare population. Using Current Procedural Terminology (CPT) and International Classification of Diseases, 9th Revision (ICD-9) procedure codes, we queried the PearlDiver database for patients undergoing elbow arthroscopy. Patients were divided into obese (body mass index [BMI] >30) and nonobese (BMI <30) cohorts using ICD-9 codes for BMI and obesity. Nonobese patients were matched to obese patients based on age, sex, tobacco use, diabetes, and rheumatoid arthritis. Postoperative complications were assessed with ICD-9 and Current Procedural Terminology codes, including infection, nerve injury, stiffness, and medical complications. A total of 2,785 Medicare patients who underwent elbow arthroscopy were identified from 2005 to 2012; 628 patients (22.5%) were coded as obese or morbidly obese, and 628 matched nonobese patients formed the control group. There were no differences between the obese patients and matched control nonobese patients regarding type of elbow arthroscopy, previous elbow fracture or previous elbow arthroscopy. Obese patients had greater rates of all assessed complications, including infection (odds ratio [OR] 2.8, P = .037), nerve injury (OR 5.4, P = .001), stiffness (OR 1.9, P = .016) and medical complications (OR 6.9, P < .0001). Obesity is associated with significantly increased rates of all assessed complications after elbow arthroscopy in a Medicare population, including infection, nerve injury, stiffness, and medical complications. Therapeutic Level III, case-control study. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Elbow mass flow meter

DOEpatents

McFarland, Andrew R.; Rodgers, John C.; Ortiz, Carlos A.; Nelson, David C.

1994-01-01

Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.

Haptic Recreation of Elbow Spasticity

PubMed Central

Kim, Jonghyun; Damiano, Diane L.

2013-01-01

The aim of this paper is to develop a haptic device capable of presenting standardized recreation of elbow spasticity. Using the haptic device, clinicians will be able to repeatedly practice the assessment of spasticity without requiring patient involvement, and these practice opportunities will help improve accuracy and reliability of the assessment itself. Haptic elbow spasticity simulator (HESS) was designed and prototyped according to mechanical requirements to recreate the feel of elbow spasticity. Based on the data collected from subjects with elbow spasticity, a mathematical model representing elbow spasticity is proposed. As an attempt to differentiate the feel of each score in Modified Ashworth Scale (MAS), parameters of the model were obtained respectively for three different MAS scores 1, 1+, and 2. The implemented haptic recreation was evaluated by experienced clinicians who were asked to give MAS scores by manipulating the haptic device. The clinicians who participated in the study were blinded to each other’s scores and to the given models. They distinguished the three models and the MAS scores given to the recreated models matched 100% with the original MAS scores from the patients. PMID:22275660

Computing muscle, ligament, and osseous contributions to the elbow varus moment during baseball pitching

PubMed Central

Buffi, James H.; Werner, Katie; Kepple, Tom; Murray, Wendy M.

2014-01-01

Baseball pitching imposes a dangerous valgus load on the elbow that puts the joint at severe risk for injury. The goal of this study was to develop a musculoskeletal modeling approach to enable evaluation of muscle-tendon contributions to mitigating elbow injury risk in pitching. We implemented a forward dynamic simulation framework that used a scaled biomechanical model to reproduce a pitching motion recorded from a high school pitcher. The medial elbow muscles generated substantial, protective, varus elbow moments in our simulations. For our subject, the triceps generated large varus moments at the time of peak valgus loading; varus moments generated by the flexor digitorum superficialis were larger, but occurred later in the motion. Increasing muscle-tendon force output, either by augmenting parameters associated with strength and power or by increasing activation levels, decreased the load on the ulnar collateral ligament. Published methods have not previously quantified the biomechanics of elbow muscles during pitching. This simulation study represents a critical advancement in the study of baseball pitching and highlights the utility of simulation techniques in the study of this difficult problem. PMID:25281409

Effect of window length on performance of the elbow-joint angle prediction based on electromyography

NASA Astrophysics Data System (ADS)

Triwiyanto; Wahyunggoro, Oyas; Adi Nugroho, Hanung; Herianto

2017-05-01

The high performance of the elbow joint angle prediction is essential on the development of the devices based on electromyography (EMG) control. The performance of the prediction depends on the feature of extraction parameters such as window length. In this paper, we evaluated the effect of the window length on the performance of the elbow-joint angle prediction. The prediction algorithm consists of zero-crossing feature extraction and second order of Butterworth low pass filter. The feature was used to extract the EMG signal by varying window length. The EMG signal was collected from the biceps muscle while the elbow was moved in the flexion and extension motion. The subject performed the elbow motion by holding a 1-kg load and moved the elbow in different periods (12 seconds, 8 seconds and 6 seconds). The results indicated that the window length affected the performance of the prediction. The 250 window lengths yielded the best performance of the prediction algorithm of (mean±SD) root mean square error = 5.68%±1.53% and Person’s correlation = 0.99±0.0059.

A CRITICAL REVIEW OF THE CURRENT CONSERVATIVE THERAPIES FOR TENNIS ELBOW (LATERAL EPICONDYLITIS)

PubMed Central

Viola, Leonardo

1998-01-01

The pathogenesis, pathology, natural course, and in particular the treatment of lateral epicondylitis (tennis elbow) remains controversial. An extensive review of the scientific literature with respect to the conservative treatment of tennis elbow, revealed that acceptable epidemiological techniques of the prospective randomised control trials or case controlled studies are scarce. While administration of steroid compounds has traditionally been the mainstay of conservative treatment of tennis elbow, the high recurrence rate of side effects and structural tissue changes associated with steroid therapy, leaves this modality as the most controversial approach in the treatment of tennis elbow. In contrast, in some studies evidence in favour of a role for classical acupuncture, ultrasound and low level laser as effective therapeutic means in the treatment of tennis elbow has been provided. As these modalities have not been associated with any side effects, in view of the ease of application, low cost and good curative effects, their increased application has been suggested by some authors. This proposition, however, remains rather conjectural until it could be convincingly substantiated by future studies with appropriate epidemiological design. PMID:17987156

A clinically oriented comprehensive pictorial review of canine elbow anatomy.

PubMed

Constantinescu, Gheorghe M; Constantinescu, Ileana A

2009-02-01

The clinically oriented canine elbow anatomy in its complexity earned a high importance in surgery especially after multiple imaging modalities have been used in the benefit of diagnosis and treatment of canine elbow disorders. The bony, joint, and muscular structures, the arteries, the veins and the nerves supplying the elbow are described and illustrated in textbooks and atlases in the context of the comparative anatomy. Nevertheless, there is no publication focused on all of these structures described together from the skin to the bones in a systematic and topographic order, nor through cross and/or sagittal and coronal sections. The figures used in this article are original and drawn after dissection, cross, sagittal, and coronal sections of the elbow structures. The sections are correlated to the multiple imaging modalities shown in the next article.

Series elastic actuation of an elbow rehabilitation exoskeleton with axis misalignment adaptation.

PubMed

Wu, Kuan-Yi; Su, Yin-Yu; Yu, Ying-Lung; Lin, Kuei-You; Lan, Chao-Chieh

2017-07-01

Powered exoskeletons can facilitate rehabilitation of patients with upper limb disabilities. Designs using rotary motors usually result in bulky exoskeletons to reduce the problem of moving inertia. This paper presents a new linearly actuated elbow exoskeleton that consists of a slider crank mechanism and a linear motor. The linear motor is placed beside the upper arm and closer to shoulder joint. Thus better inertia properties can be achieved while lightweight and compactness are maintained. A passive joint is introduced to compensate for the exoskeleton-elbow misalignment and intersubject size variation. A linear series elastic actuator (SEA) is proposed to obtain accurate force and impedance control at the exoskeleton-elbow interface. Bidirectional actuation between exoskeleton and forearm is verified, which is required for various rehabilitation processes. We expect this exoskeleton can provide a means of robot-aided elbow rehabilitation.

Accuracy in identifying the elbow rotation axis on simulated fluoroscopic images using a new anatomical landmark.

PubMed

Wiggers, J K; Snijders, R M; Dobbe, J G G; Streekstra, G J; den Hartog, D; Schep, N W L

2017-11-01

External fixation of the elbow requires identification of the elbow rotation axis, but the accuracy of traditional landmarks (capitellum and trochlea) on fluoroscopy is limited. The relative distance (RD) of the humerus may be helpful as additional landmark. The first aim of this study was to determine the optimal RD that corresponds to an on-axis lateral image of the elbow. The second aim was to assess whether the use of the optimal RD improves the surgical accuracy to identify the elbow rotation axis on fluoroscopy. CT scans of elbows from five volunteers were used to simulate fluoroscopy; the actual rotation axis was calculated with CT-based flexion-extension analysis. First, three observers measured the optimal RD on simulated fluoroscopy. The RD is defined as the distance between the dorsal part of the humerus and the projection of the posteromedial cortex of the distal humerus, divided by the anteroposterior diameter of the humerus. Second, eight trauma surgeons assessed the elbow rotation axis on simulated fluoroscopy. In a preteaching session, surgeons used traditional landmarks. The surgeons were then instructed how to use the optimal RD as additional landmark in a postteaching session. The deviation from the actual rotation axis was expressed as rotational and translational error (±SD). Measurement of the RD was robust and easily reproducible; the optimal RD was 45%. The surgeons identified the elbow rotation axis with a mean rotational error decreasing from 7.6° ± 3.4° to 6.7° ± 3.3° after teaching how to use the RD. The mean translational error decreased from 4.2 ± 2.0 to 3.7 ± 2.0 mm after teaching. The humeral RD as additional landmark yielded small but relevant improvements. Although fluoroscopy-based external fixator alignment to the elbow remains prone to error, it is recommended to use the RD as additional landmark.

Elbow stress indices using finite element analysis

NASA Astrophysics Data System (ADS)

Yu, Lixin

Section III of the ASME Boiler and Pressure Vessel Code (the Code) specifies rules for the design of nuclear power plant components. NB-3600 of the Code presents a simplified design method using stress indices---Scalar Coefficients used the modify straight pipe stress equations so that they can be applied to elbows, tees and other piping components. The stress indices of piping components are allowed to be determined both analytically and experimentally. This study concentrates on the determination of B2 stress indices for elbow components using finite element analysis (FEA). First, the previous theoretical, numerical and experimental investigations on elbow behavior were comprehensively reviewed, as was the philosophy behind the use of stress indices. The areas of further research was defined. Then, a comprehensive investigation was carried out to determine how the finite element method should be used to correctly simulate an elbow's structural behavior. This investigation included choice of element type, convergence of mesh density, use of boundary restraint and a reconciliation study between FEA and laboratory experiments or other theoretical formulations in both elastic and elasto-plastic domain. Results from different computer programs were also compared. Reasonably good reconciliation was obtained. Appendix II of the Code describes the experimental method to determine B2 stress indices based on load-deflection curves. This procedure was used to compute the B2 stress indices for various loading modes on one particular elbow configuration. The B2 stress indices thus determined were found to be about half of the value calculated from the Code equation. Then the effect on B2 stress indices of those factors such as internal pressure and flange attachments were studied. Finally, the investigation was extended to other configurations of elbow components. A parametric study was conducted on different elbow sizes and schedules. Regression analysis was then used to obtain a modified coefficient and exponent for the Code equation used to calculate B2 index for elbows.

Elbow Joint Fatigue and Bench-Press Training

PubMed Central

Huang, Yen-Po; Chou, You-Li; Chen, Feng-Chun; Wang, Rong-Tyai; Huang, Ming-Jer; Chou, Paul Pei-Hsi

2014-01-01

Context: Bench-press exercises are among the most common form of training exercise for the upper extremity because they yield a notable improvement in both muscle strength and muscle endurance. The literature contains various investigations into the effects of different bench-press positions on the degree of muscle activation. However, the effects of fatigue on the muscular performance and kinetics of the elbow joint are not understood fully. Objective: To investigate the effects of fatigue on the kinetics and myodynamic performance of the elbow joint in bench-press training. Design: Controlled laboratory study. Setting: Motion research laboratory. Patients or Other Participants: A total of 18 physically healthy male students (age = 19.6 ± 0.8 years, height = 168.7 ± 5.5 cm, mass = 69.6 ± 8.6 kg) participated in the investigation. All participants were right-hand dominant, and none had a history of upper extremity injuries or disorders. Intervention(s): Participants performed bench-press training until fatigued. Main Outcome Measure(s): Maximal possible number of repetitions, cycle time, myodynamic decline rate, elbow-joint force, and elbow-joint moment. Results: We observed a difference in cycle time in the initial (2.1 ± 0.42 seconds) and fatigue (2.58 ± 0.46 seconds) stages of the bench-press exercise (P = .04). As the participants fatigued, we observed an increase in the medial-lateral force (P = .03) and internal-external moment (P ≤ .04) acting on the elbow joint. Moreover, a reduction in the elbow muscle strength was observed in the elbow extension-flexion (P ≤ .003) and forearm supination-pronation (P ≤ .001) conditions. Conclusions: The results suggest that performing bench-press exercises to the point of fatigue increases elbow-joint loading and may further increase the risk of injury. Therefore, when clinicians design bench-press exercise regimens for general athletic training, muscle strengthening, or physical rehabilitation, they should control carefully the maximal number of repetitions. PMID:24533529

Biomechanics of the elbow joint in tennis players and relation to pathology

PubMed Central

Eygendaal, Denise; Rahussen, F T G; Diercks, R L

2007-01-01

Elbow injuries constitute a sizeable percentage of tennis injuries. A basic understanding of biomechanics of tennis and analysis of the forces, loads and motions of the elbow during tennis will improve the understanding of the pathophysiology of these injuries. All different strokes in tennis have a different repetitive biomechanical nature that can result in tennis‐related injuries. In this article, a biomechanically‐based evaluation of tennis strokes is presented. This overview includes all tennis‐related pathologies of the elbow joint, whereby the possible relation of biomechanics to pathology is analysed, followed by treatment recommendations. PMID:17638843

MR imaging of the elbow in the injured athlete.

PubMed

Wenzke, Daniel R

2013-03-01

This article summarizes key MR imaging findings in common athletic elbow injuries including little leaguer's elbow, Panner disease, osteochondritis dissecans, olecranon stress fracture, occult fracture, degenerative osteophyte formation, flexor-pronator strain, ulnar collateral ligament tear, lateral ulnar collateral ligament and radial collateral ligament tear, lateral epicondylitis, medial epicondylitis, biceps tear, bicipitoradial bursitis, triceps tear, olecranon bursitis, ulnar neuropathy, posterior interosseous nerve syndrome, and radial tunnel syndrome. The article also summarizes important technical considerations in elbow MR imaging that enhance image quality and contribute to the radiologist's success. Copyright © 2013 Elsevier Inc. All rights reserved.

Biomechanics of the elbow joint in tennis players and relation to pathology.

PubMed

Eygendaal, Denise; Rahussen, F Th G; Diercks, R L

2007-11-01

Elbow injuries constitute a sizeable percentage of tennis injuries. A basic understanding of biomechanics of tennis and analysis of the forces, loads and motions of the elbow during tennis will improve the understanding of the pathophysiology of these injuries. All different strokes in tennis have a different repetitive biomechanical nature that can result in tennis-related injuries. In this article, a biomechanically-based evaluation of tennis strokes is presented. This overview includes all tennis-related pathologies of the elbow joint, whereby the possible relation of biomechanics to pathology is analysed, followed by treatment recommendations.

A comparison of manual and quantitative elbow strength testing.

PubMed

Shahgholi, Leili; Bengtson, Keith A; Bishop, Allen T; Shin, Alexander Y; Spinner, Robert J; Basford, Jeffrey R; Kaufman, Kenton R

2012-10-01

The aim of this study was to compare the clinical ratings of elbow strength obtained by skilled clinicians with objective strength measurement obtained through quantitative testing. A retrospective comparison of subject clinical records with quantitative strength testing results in a motion analysis laboratory was conducted. A total of 110 individuals between the ages of 8 and 65 yrs with traumatic brachial plexus injuries were identified. Patients underwent manual muscle strength testing as assessed on the 5-point British Medical Research Council Scale (5/5, normal; 0/5, absent) and quantitative elbow flexion and extension strength measurements. A total of 92 subjects had elbow flexion testing. Half of the subjects clinically assessed as having normal (5/5) elbow flexion strength on manual muscle testing exhibited less than 42% of their age-expected strength on quantitative testing. Eighty-four subjects had elbow extension strength testing. Similarly, half of those displaying normal elbow extension strength on manual muscle testing were found to have less than 62% of their age-expected values on quantitative testing. Significant differences between manual muscle testing and quantitative findings were not detected for the lesser (0-4) strength grades. Manual muscle testing, even when performed by experienced clinicians, may be more misleading than expected for subjects graded as having normal (5/5) strength. Manual muscle testing estimates for the lesser strength grades (1-4/5) seem reasonably accurate.

Distal nerve transfer versus supraclavicular nerve grafting: comparison of elbow flexion outcome in neonatal brachial plexus palsy with C5-C7 involvement.

PubMed

Heise, Carlos O; Siqueira, Mario G; Martins, Roberto S; Foroni, Luciano H; Sterman-Neto, Hugo

2017-09-01

Ulnar and median nerve transfers to arm muscles have been used to recover elbow flexion in infants with neonatal brachial plexus palsy, but there is no direct outcome comparison with the classical supraclavicular nerve grafting approach. We retrospectively analyzed patients with C5-C7 neonatal brachial plexus palsy submitted to nerve surgery and recorded elbow flexion recovery using the active movement scale (0-7) at 12 and 24 months after surgery. We compared 13 patients submitted to supraclavicular nerve grafting with 21 patients submitted to distal ulnar or median nerve transfer to biceps motor branch. We considered elbow flexion scores of 6 or 7 as good results. The mean elbow flexion score and the proportion of good results were better using distal nerve transfers than supraclavicular grafting at 12 months (p < 0.01), but not at 24 months. Two patients with failed supraclavicular nerve grafting at 12 months showed good elbow flexion recovery after ulnar nerve transfers. Distal nerve transfers provided faster elbow flexion recovery than supraclavicular nerve grafting, but there was no significant difference in the outcome after 24 months of surgery. Patients with failed supraclavicular grafting operated early can still benefit from late distal nerve transfers. Supraclavicular nerve grafting should remain as the first line surgical treatment for children with neonatal brachial plexus palsy.

In vivo axial humero-ulnar rotation in normal and dysplastic canine elbow joints.

PubMed

Rohwedder, Thomas; Fischer, Martin; Böttcher, Peter

2018-04-01

To prospectively compare relative axial (internal-external) humero-ulnar rotation in normal and dysplastic canine elbow joints. Six normal elbows (five dogs) and seven joints (six dogs) with coronoid disease were examined. After implantation of 0.8 mm tantalum beads into humerus and ulna, biplanar x-ray movies of the implanted elbows were taken while dogs were walking on a treadmill. Based on the 2D bead coordinates of the synchronized x-ray movies virtual 3D humero-ulnar animations were calculated. Based on these, relative internal-external humero-ulnar rotation was measured over the first third of stance phase and expressed as maximal rotational amplitude. Amplitudes from three consecutive steps were averaged and groupwise compared using an unpaired t-test. In normal elbow joints mean axial relative humero-ulnar rotation was 2.9° (SD 1.1). Dysplastic joints showed a significantly greater rotational amplitude (5.3°, SD 2.0; p = 0.0229, 95% confidence interval 0.4-4.4). Dysplastic elbow joints show greater relative internal-external humero-ulnar rotation compared to normal elbows, which might reflect rotational joint instability. Increased relative internal-external humero-ulnar rotation might alter physiological joint contact and pressure patterns. Future studies are needed to verify if this plays a role in the pathogenesis of medial coronoid disease. Schattauer GmbH.

Dural ectasia in a child with Larsen syndrome.

PubMed

Jain, Viral V; Anadio, Jennifer M; Chan, Gilbert; Sturm, Peter F; Crawford, Alvin H

2014-01-01

We present a case of an incidental finding of dural ectasia in a child diagnosed with Larsen syndrome. Larsen syndrome is a rare inherited disorder of connective tissue characterized by facial dysmorphism, congenital joint dislocations of the hips, knees and elbows, and deformities of the hands and feet. Dural ectasia is as an abnormal expansion of the dural sac surrounding the spinal cord and may result in spinal morphologic changes, instability, and spontaneous dislocation. To the best of our knowledge, the presence of dural ectasia in Larsen syndrome has not previously been reported. A 6-year-old boy diagnosed with Larsen syndrome presented with an upper thoracic curve measuring 74 degrees, a right thoracic curve measuring 65 degrees, and significant cervicothoracic kyphosis with 50% anterior subluxation of C6 on C7 and C7 on T1. Advanced imaging studies showed dural ectasia (evidenced by spinal canal and dural sac expansion), thinning of pedicles and lamina, and C4 and C6 pars defects with cervical foramen enlargement. The patient received growing rod instrumentation (attached to cervical spine fixation) by a combined anterior/posterior surgical approach using intraoperative halo. Complications included intraoperative medial breach (fully resolved), wound dehiscence, 2 instances of bilateral broken rods, and a broken cervical rod. Following 7 lengthening procedures, the patient underwent definitive fusion. Surgeons should be aware of the potential for dural ectasia in patients with Larsen syndrome. Its presence will cause difficulties in the surgical intervention for spinal deformity. Multiple factors must be considered, and surgical approach and technique will require modification to avoid complications. Although dural ectasia confounds surgical intervention in these patients, surgery still appears to outweigh the risks associated with delayed intervention. The presence of dural ectasia should not preclude surgical decompression and stabilization. This report adds to the body of knowledge on the treatment of Larsen syndrome by demonstrating the potential existence of dural ectasia and highlights the importance of careful and thorough preoperative evaluation and diagnostic imaging.

Image-guided elbow interventions: a literature review of interventional treatment options

PubMed Central

Sorani, Alan

2016-01-01

Over the years, a wide range of image-guided interventional therapies have been used in treating different elbow pathologies, many of which are predominantly based on anecdotal and low-level study findings. This article critically assesses the existing literature and discusses the efficacy of the most commonly utilized interventional procedures for elbow pathology. PMID:26206415

Exposures of the elbow.

PubMed

Axelrod, Terry S

2014-11-01

This article describes the basic bony, ligamentous, and neurologic anatomy of the structures about the elbow. The surgical exposures of the elbow joint are described, providing details of the various posterior, lateral, and medial approaches to the articular segments. Clinical applications describing the potential benefits of each surgical exposure are provided as examples. Copyright © 2014 Elsevier Inc. All rights reserved.

49 CFR 192.313 - Bends and elbows.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Bends and elbows. 192.313 Section 192.313... Lines and Mains § 192.313 Bends and elbows. (a) Each field bend in steel pipe, other than a wrinkle bend made in accordance with § 192.315, must comply with the following: (1) A bend must not impair the...

49 CFR 192.313 - Bends and elbows.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 3 2011-10-01 2011-10-01 false Bends and elbows. 192.313 Section 192.313... Lines and Mains § 192.313 Bends and elbows. (a) Each field bend in steel pipe, other than a wrinkle bend made in accordance with § 192.315, must comply with the following: (1) A bend must not impair the...

Early results of Latitude primary total elbow replacement with a minimum follow-up of 2 years.

PubMed

Mehta, Saurabh S; Watts, Adam C; Talwalkar, Sumedh C; Birch, Ann; Nuttall, David; Trail, Ian A

2017-10-01

The aim of this study was to present outcomes of primary Latitude total elbow replacement (TER) with a minimum follow-up of 2 years. A retrospective cohort study was undertaken with prospective outcome data collection for the latest outcome. Included were 63 consecutive primary Latitude TERs in 58 patients performed during a period of 5 years at a specialist orthopedic hospital. The mean age of the patients was 62 years (33-85 years). Five primary TERs (4 patients) were lost to follow-up. The primary diagnosis was rheumatoid arthritis in 49, osteoarthritis in 8, and trauma in 6 elbows. The mean flexion-extension arc was 75° preoperatively and 97° postoperatively. Mean postoperative Elbex pain score was 19/100, and function score was 37/100. Mean postoperative scores were 42/100 for the Quick Disabilities of the Arm, Shoulder, and Hand and 38/50 for the elbow-specific American Shoulder and Elbow Surgeons assessment. Four patients died of unrelated causes, and 8 of 63 underwent further surgical intervention, including explantation and conversion from unlinked to linked implant. On radiographic review of 41 surviving TERs, aseptic radiologic loosening was observed of the humeral component in 4 elbows and of the ulnar component in 9. Seven elbows had no radial component, and of the remaining 34 elbows, 16 (47%) had signs of loosening of the radial implant. Complications included 1 heterotopic ossification, 1 olecranon fracture, and 3 further procedures for ulnar nerve entrapment. The results indicate that the early outcome of Latitude TER is comparable to that of other prostheses. There is concern about early radiologic loosening of the radial component. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

Shoulder and elbow pain in elementary school baseball players: The results from a nation-wide survey in Japan.

PubMed

Takagishi, Kenji; Matsuura, Tetsuya; Masatomi, Takashi; Chosa, Etsuo; Tajika, Tsuyoshi; Watanabe, Mikihiko; Iwama, Tetsu; Otani, Toshiro; Inagaki, Katsunori; Ikegami, Hiroyasu; Aoki, Mitsuhiro; Kato, Ko; Okuwaki, Toru; Sairyo, Koichi; Kameyama, Yasushi; Maeda, Akira; Beppu, Moroe

2017-07-01

Despite recommendations on how to prevent baseball injuries in youths by the Japanese Society of Clinical Sports Medicine, shoulder and elbow pain still frequently occurs in young baseball players. We conducted a questionnaire survey among baseball players at elementary schools across the country to understand the practice conditions of players, examining the risk factors of shoulder and elbow pain in baseball players. The questionnaire survey was conducted among elementary school baseball players as members of the Baseball Federation of Japan in September 2015. A total of 8354 players belonging to 412 teams (average age: 8.9) responded to the survey. Among 7894 players who did not have any shoulder and/or elbow pain in September 2014, elbow pain was experienced in 12.3% of them, shoulder pain in 8.0% and shoulder and/or elbow pain in 17.4% during the previous one year. A total of 2835 (39.9% of the total) practiced four days or more per week and 97.6% practiced 3 h or more per day on Saturdays and Sundays. The risk factors associated shoulder and elbow pain included a male sex, older age, pitchers and catchers, and players throwing more than 50 balls per day. It has been revealed that Japanese elementary school baseball players train too much. Coaches should pay attention to older players, male players, pitchers and catchers in order to prevent shoulder and elbow pain. Furthermore, elementary school baseball players should not be allowed to throw more than 50 balls per day. Retrospective cohort study. Copyright © 2017 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

Risk factors for cartilage damage and osteoarthritis of the elbow joint: case-control study and systematic literature review.

PubMed

Spahn, Gunter; Lipfert, Jens Uwe; Maurer, Constance; Hartmann, Bernd; Schiele, Rainer; Klemm, Holm-Torsten; Grifka, Joachim; Hofmann, Gunther O

2017-04-01

This case-control study compares patients with healthy elbows to a group of symptomatic patients with cartilage damage/osteoarthritis. The control group (n = 126) was recruited during routine medical examinations of patients (general medical offices). Included in the case group were a total of 92 patients who were undergoing arthroscopy as a result of chronic elbow discomfort. All patients were questioned with regard to occupational stress and athletic stress. A significantly increased risk of cartilage damage/osteoarthritis was found with subjectively perceived increased stress in occupational settings: OR = 3.8 (95% CI 2.1-6.7); p < 0.001; for the individual stresses of the elbow joint in occupational settings, the following severities in effects were found: Exposure to heavy work OR = 3.9 (95% CI 2.2-6.8); Force OR = 3.7 (95% CI 2.1-6.5); Vibration OR = 4.6 (95% CI 2.5-8.5); Repetition OR = 9.2 (95% CI 3.6-23.3); p < 0.001. Elbow-stressing sport types represent a potential risk factor for the development of cartilage damage/osteoarthritis of the elbow joint: OR = 2.5 (95% CI 1.3-4.7); p = 0.003. Cartilage damage/radiographic osteoarthritis of the elbow joint are rare with respect to the overall prevalence of osteoarthritis. In the large number of patients with cartilage damage/radiographic osteoarthritis of the elbow joint, occupational or athletic stress factors and injuries sustained, in addition to other causes (rheumatism, gout), can prove as possible causes of these as secondary to symptomatic forms of osteoarthritis.

In vivo and 3-dimensional functional anatomy of the anterior bundle of the medial collateral ligament of the elbow.

PubMed

Miyake, Junichi; Moritomo, Hisao; Masatomi, Takashi; Kataoka, Toshiyuki; Murase, Tsuyoshi; Yoshikawa, Hideki; Sugamoto, Kazuomi

2012-08-01

Although the anterior bundle of the medial collateral ligament (AMCL) is a critical stabilizer of the elbow joint, little information exists on in vivo and 3-dimensional functional anatomy of the AMCL. The purposes of this study were to investigate in vivo changes in the length of the AMCL during elbow flexion and to clarify the 3-dimensional functional anatomy of the AMCL. We created 3-dimensional models of the AMCL and bones from computed tomography data of 4 healthy elbows in 5 different elbow positions. The AMCL was subdivided into 9 ligaments. We calculated changes in lengths of ligaments during flexion and related ligament origins to the axis of rotation of the elbow joint. There were 4 uniquely configured isometric ligaments, where their origins aligned broadly along the course of the axis of rotation in the coronal plane. The medially originating ligaments inserted on the posterior portion of the tubercle of the coronoid process, whereas the laterally originating ligaments inserted on its anterior portion. There were 5 non-isometric ligaments, 3 of which had origins proximal to the axis and became taut only in extension and the other 2 having origins distal to the axis and becoming taut only in flexion. Isometric ligaments within the AMCL do not originate from a narrow area; rather, they originate from a broader area that extends more medially in the coronal plane than previously thought, which explains how the AMCL reconciles isometricity and robustness. The proximal and distal ligaments act as checkreins that work only at the limits of elbow motion. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Validation of a photography-based goniometry method for measuring joint range of motion.

PubMed

Blonna, Davide; Zarkadas, Peter C; Fitzsimmons, James S; O'Driscoll, Shawn W

2012-01-01

A critical component of evaluating the outcomes after surgery to restore lost elbow motion is the range of motion (ROM) of the elbow. This study examined if digital photography-based goniometry is as accurate and reliable as clinical goniometry for measuring elbow ROM. Instrument validity and reliability for photography-based goniometry were evaluated for a consecutive series of 50 elbow contractures by 4 observers with different levels of elbow experience. Goniometric ROM measurements were taken with the elbows in full extension and full flexion directly in the clinic (once) and from digital photographs (twice in a blinded random manner). Instrument validity for photography-based goniometry was extremely high (intraclass correlation coefficient: extension = 0.98, flexion = 0.96). For extension and flexion measurements by the expert surgeon, systematic error was negligible (0° and 1°, respectively). Limits of agreement were 7° (95% confidence interval [CI], 5° to 9°) and -7° (95% CI, -5° to -9°) for extension and 8° (95% CI, 6° to 10°) and -7° (95% CI, -5° to -9°) for flexion. Interobserver reliability for photography-based goniometry was better than that for clinical goniometry. The least experienced observer's photographic goniometry measurements were closer to the reference measurements than the clinical goniometry measurements. Photography-based goniometry is accurate and reliable for measuring elbow ROM. The photography-based method relied less on observer expertise than clinical goniometry. This validates an objective measure of patient outcome without requiring doctor-patient contact at a tertiary care center, where most contracture surgeries are done. Copyright © 2012 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Flexor bias of joint position in humans during spaceflight

NASA Technical Reports Server (NTRS)

McCall, G. E.; Goulet, C.; Boorman, G. I.; Roy, R. R.; Edgerton, V. R.

2003-01-01

The ability to estimate ankle and elbow joint position was tested before, during, and after a 17-day spaceflight. Subjects estimated targeted joint angles during isovelocity (IsoV) joint movements with agonist muscle groups either active or relaxed. These movements included elbow extension (EE) and elbow flexion (EF), and plantarflexion (PF) and dorsiflexion (DF) of the ankle. Subjects also estimated these joint positions while moving the dynamometer at their chosen (variable) velocity (VarV) during EE and PF. For IsoV tests, no differences were observed between active and passive movements for either the ankle or elbow. Compared with those of pre-flight test days, estimates of targeted elbow joint angles were approximately 5 degrees to 15 degrees more flexed in-flight, and returned toward the pre-flight values during recovery. The spaceflight effects for the ankle were inconsistent and less prevalent than those for the elbow. The VarV PF test condition for the 120 degrees target angle at the ankle exhibited approximately 5 degrees to 7 degrees more DF target angle estimates in-flight compared with those pre- or post-flight. In contrast, during IsoV PF there was a tendency for ankle estimates to be approximately 2 degrees to 3 degrees more PF after 2-3 days exposure to spaceflight. These data indicate that during spaceflight the perception of elbow extension is greater than actuality, and are consistent with the interpretation that microgravity induced a flexor bias in the estimation of the actual elbow joint position. Moreover, these effects in joint proprioception during spaceflight were observed in individual isolated single-joint movements during tasks in which vestibular function in maintaining posture were minimal.

Percutaneous ultrasonic tenotomy for chronic elbow tendinosis: a prospective study.

PubMed

Barnes, Darryl E; Beckley, James M; Smith, Jay

2015-01-01

Elbow tendinopathy is the most common cause of elbow pain affecting active populations. Surgical excision is reserved for patients with refractory symptoms. Percutaneous ultrasonic tenotomy performed under local anesthesia also removes degenerated tissue and therefore provides an alternative treatment option to surgical excision. This investigation prospectively documented the safety and 1-year efficacy of ultrasonic percutaneous tenotomy performed by a single operator. Nineteen patients, aged 38 to 67 years, in whom >6 months of conservative management for medial (7) or lateral (12) elbow tendinopathy had failed were prospectively studied. All patients were treated with percutaneous ultrasonic tenotomy of the elbow by a single operator. Visual analog scale (VAS) for pain, the 11-item version of the Disabilities of the Arm, Shoulder, and Hand (Quick DASH) index, and the Mayo Elbow Performance Score (MEPS) were assessed by an independent observer before treatment and at 6 weeks, 3 months, 6 months, and 12 months after treatment. No procedural complications occurred. Total treatment time was <15 minutes, and ultrasonic energy time averaged 38.6 ± 8.8 seconds per procedure. Average VAS scores were significantly improved from 6.4 to 2.6 at 6 weeks and were 0.7 at 12 months (P < .0001). Similar improvement occurred with the Quick DASH (pretreatment, 44.1; 12 months, 8.6, P < .0001) and MEPS (pretreatment, 59.1; 12 months, 83.4; P < .0001). Percutaneous ultrasonic tenotomy performed under local anesthesia appears to be a safe and effective treatment option for chronic, refractory lateral or medial elbow tendinopathy up to 1 year after the procedure. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Flexor bias of joint position in humans during spaceflight.

PubMed

McCall, G E; Goulet, C; Boorman, G I; Roy, R R; Edgerton, V R

2003-09-01

The ability to estimate ankle and elbow joint position was tested before, during, and after a 17-day spaceflight. Subjects estimated targeted joint angles during isovelocity (IsoV) joint movements with agonist muscle groups either active or relaxed. These movements included elbow extension (EE) and elbow flexion (EF), and plantarflexion (PF) and dorsiflexion (DF) of the ankle. Subjects also estimated these joint positions while moving the dynamometer at their chosen (variable) velocity (VarV) during EE and PF. For IsoV tests, no differences were observed between active and passive movements for either the ankle or elbow. Compared with those of pre-flight test days, estimates of targeted elbow joint angles were approximately 5 degrees to 15 degrees more flexed in-flight, and returned toward the pre-flight values during recovery. The spaceflight effects for the ankle were inconsistent and less prevalent than those for the elbow. The VarV PF test condition for the 120 degrees target angle at the ankle exhibited approximately 5 degrees to 7 degrees more DF target angle estimates in-flight compared with those pre- or post-flight. In contrast, during IsoV PF there was a tendency for ankle estimates to be approximately 2 degrees to 3 degrees more PF after 2-3 days exposure to spaceflight. These data indicate that during spaceflight the perception of elbow extension is greater than actuality, and are consistent with the interpretation that microgravity induced a flexor bias in the estimation of the actual elbow joint position. Moreover, these effects in joint proprioception during spaceflight were observed in individual isolated single-joint movements during tasks in which vestibular function in maintaining posture were minimal.

Elbow hemiarthroplasty using a "triceps-on" approach for the management of acute distal humeral fractures.

PubMed

Phadnis, Joideep; Banerjee, Samik; Watts, Adam C; Little, Nicholas; Hearnden, Anthony; Patel, Vipul R

2015-08-01

Total elbow arthroplasty is an established option for the primary treatment of acute distal humeral fractures, but there are sparse data regarding elbow hemiarthroplasty (EHA) as an alternative. We present the outcome of EHA performed with a modular anatomic prosthesis and a "triceps-on" surgical technique. Eighteen consecutive patients underwent EHA for an acute fracture. Two patients died, leaving a study group of 16 patients with minimum 2-year follow-up. Clinical evaluation included range of motion; Mayo Elbow Performance Score; Quick Disabilities of the Arm, Shoulder, and Hand score; and Oxford Elbow Score. Radiographic assessment looked at alignment, evidence of loosening, ulnar and radial head wear, heterotopic ossification, and whether healing of the condyles had occurred. Mean follow-up was 35 months (24-79 months). The mean scores were as follows: Mayo Elbow Performance Score, 89.6; shortened Disabilities of the Arm, Shoulder, and Hand score, 11.2; and Oxford Elbow Score, 43.7. The mean flexion and pronation-supination arcs were 116° and 172° respectively. Radial head wear was absent in 13 patients and mild in 3. Ulnar wear was absent in 6 patients, mild in 8, and moderate in 2. Wear was not associated with greater pain or inferior functional scores. There was no sign of aseptic loosening, and complete condylar bone union occurred in 15 elbows. There was 1 complication, a transient ulnar nerve neurapraxia that resolved without intervention. EHA with a modular anatomic implant using a triceps-on approach is a reliable technique for the management of acute unreconstructible distal humeral fractures in older patients. Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.

Results of Operative and Nonoperative Treatment of Rockwood Types III and V Acromioclavicular Joint Dislocation

PubMed Central

Joukainen, Antti; Kröger, Heikki; Niemitukia, Lea; Mäkelä, E. Antero; Väätäinen, Urho

2014-01-01

Background: The optimal treatment of acute, complete dislocation of the acromioclavicular joint (ACJ) is still unresolved. Purpose: To determine the difference between operative and nonoperative treatment in acute Rockwood types III and V ACJ dislocation. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: In the operative treatment group, the ACJ was reduced and fixed with 2 transarticular Kirschner wires and ACJ ligament suturing. The Kirschner wires were extracted after 6 weeks. Nonoperatively treated patients received a reduction splint for 4 weeks. At the 18- to 20-year follow-up, the Constant, University of California at Los Angeles Shoulder Rating Scale (UCLA), Larsen, and Simple Shoulder Test (SST) scores were obtained, and clinical and radiographic examinations of both shoulders were performed. Results: Twenty-five of 35 potential patients were examined at the 18- to 20-year follow-up. There were 11 patients with Rockwood type III and 14 with type V dislocations. Delayed surgical treatment for ACJ was used in 2 patients during follow-up: 1 in the operatively treated group and 1 in the nonoperatively treated group. Clinically, ACJs were statistically significantly less prominent or unstable in the operative group than in the nonoperative group (normal/prominent/unstable: 9/4/3 and 0/6/3, respectively; P = .02) and in the operative type III (P = .03) but not type V dislocation groups. In operatively and nonoperatively treated patients, the mean Constant scores were 83 and 85, UCLA scores 25 and 27, Larsen scores 11 and 11, and SST scores 11 and 12 at follow-up, respectively. There were no statistically significant differences in type III and type V dislocations. In the radiographic analysis, the ACJ was wider in the nonoperative than the operative group (8.3 vs 3.4 mm; P = .004), and in the type V dislocations (nonoperative vs operative: 8.5 vs 2.4 mm; P = .007). There was no statistically significant difference between study groups in the elevation of the lateral end of the clavicle. Both groups showed equal levels of radiologic signs of ACJ osteoarthritis and calcification of the coracoclavicular ligaments. Conclusion: Nonoperative treatment was shown to produce more prominent or unstable and radiographically wider ACJs than was operative treatment, but clinical results were equally good in the study groups at 18- to 20-year follow-up. Both treatment methods showed statistically significant radiographic elevations of the lateral clavicle when compared with a noninjured ACJ. PMID:26535287

Use of an elastic transarticular external fixator construct for immobilization of the elbow joint.

PubMed

Vedrine, Bertrand

2017-04-01

Transarticular external skeletal fixation usually involves rigid bars that result in a stable but stiff joint. This study describes the technique and the outcome of an elastic transarticular external fixator (ETEF) applied to the elbow joint. Four cases of elbow luxation with collateral ligament injuries were managed with closed reduction and application of an ETEF to maintain the reduction. A triceps tendon avulsion was surgically managed before applying an ETEF. The clinical outcome was considered excellent in 2 cats, good in 2 dogs (1 elbow luxation and the avulsion of the triceps tendon), and poor in 1 dog presented for elbow luxation and a permanent neurological defect. The procedure was rapid, easy to perform, and inexpensive. All animals except the one with a neurological defect had an early return to weight bearing. This method maintains extension of the joint while permitting its motion thereby promoting rehabilitation.

Management of tennis elbow by Agnikarma.

PubMed

Mahanta, Vyasadeva; Dudhamal, Tukaram S; Gupta, Sanjay Kumar

2013-01-01

Tennis elbow is a painful condition and causes restricted movement of forearm which requires treatment for long period. Till date only symptomatic treatments are available like use of anti-inflammatory analgesic drugs, steroids injection, physiotherapy, exercise etc. But none of these provide satisfactory result. Long term use of anti-inflammatory, analgesic drugs and steroids injection is also not free from the adverse effects. Usually, 'wait-and-see policy' of treatment guideline is recommended in most of medical texts. According to Ayurveda, snayugata vata can be correlated with the condition of tennis elbow. Sushruta has advised Agnikarma for disorders of snayu (ligaments and tendons), asthi (bone), siddhi (joints) etc. Hence, in this study a case of tennis elbow (snayugata vata) was treated by Agnikarma, along with administration of powder of Ashwagandha and Navajivana Rasa orally, for a period of 03 weeks. This combination therapy provided considerable relief in pain and movement of the elbow joint.

Use of an elastic transarticular external fixator construct for immobilization of the elbow joint

PubMed Central

Vedrine, Bertrand

2017-01-01

Transarticular external skeletal fixation usually involves rigid bars that result in a stable but stiff joint. This study describes the technique and the outcome of an elastic transarticular external fixator (ETEF) applied to the elbow joint. Four cases of elbow luxation with collateral ligament injuries were managed with closed reduction and application of an ETEF to maintain the reduction. A triceps tendon avulsion was surgically managed before applying an ETEF. The clinical outcome was considered excellent in 2 cats, good in 2 dogs (1 elbow luxation and the avulsion of the triceps tendon), and poor in 1 dog presented for elbow luxation and a permanent neurological defect. The procedure was rapid, easy to perform, and inexpensive. All animals except the one with a neurological defect had an early return to weight bearing. This method maintains extension of the joint while permitting its motion thereby promoting rehabilitation. PMID:28373726

Conservative management of the post-traumatic stiff elbow: a physiotherapist’s perspective

PubMed Central

2016-01-01

Elbow stiffness is a common consequence following trauma with the management of this condition posing a challenge to therapists and surgeons alike. This paper discusses the role of conservative treatment, such as exercise and splinting, in the prevention and management of the stiff elbow, along with a review of available evidence, to justify their usage. PMID:27583012

Pediatric sports elbow injuries.

PubMed

Greiwe, R Michael; Saifi, Comron; Ahmad, Christopher S

2010-10-01

Elbow injuries in the pediatric and adolescent population represent a spectrum of pathology that can be categorized as medial tension injuries, lateral compression injuries, and posterior shear injuries. Early and accurate diagnosis can improve outcomes for both nonoperative and operative treatments. Prevention strategies are important to help reduce the increasing incidence of elbow injuries in youth athletes. Copyright © 2010 Elsevier Inc. All rights reserved.

Analysis of elbow-joints misalignment in upper-limb exoskeleton.

PubMed

Malosio, Matteo; Pedrocchi, Nicola; Vicentini, Federico; Tosatti, Lorenzo Molinari

2011-01-01

This paper presents advantages of introducing elbow-joints misalignments in an exoskeleton for upper limb rehabilitation. Typical exoskeletons are characterized by axes of the device as much as possible aligned to the rotational axes of human articulations. This approach leads to advantages in terms of movements and torques decoupling, but can lead to limitations nearby the elbow singular configuration. A proper elbow axes misalignment between the exoskeleton and the human can improve the quality of collaborative rehabilitation therapies, in which a correct torque transmission from human articulations to mechanical joints of the device is required to react to torques generated by the patient. © 2011 IEEE

Clinical anatomy of the elbow and shoulder.

PubMed

Villaseñor-Ovies, Pablo; Vargas, Angélica; Chiapas-Gasca, Karla; Canoso, Juan J; Hernández-Díaz, Cristina; Saavedra, Miguel Ángel; Navarro-Zarza, José Eduardo; Kalish, Robert A

The elbow patients herein discussed feature common soft tissue conditions such as tennis elbow, golfers' elbow and olecranon bursitis. Relevant anatomical structures for these conditions can easily be identified and demonstrated by cross examination by instructors and participants. Patients usually present rotator cuff tendinopathy, frozen shoulder, axillary neuropathy and suprascapular neuropathy. The structures involved in tendinopathy and frozen shoulder can be easily identified and demonstrated under normal conditions. The axillary and the suprascapular nerves have surface landmarks but cannot be palpated. In neuropathy however, physical findings in both neuropathies are pathognomonic and will be discussed. Copyright © 2012 Elsevier España, S.L. All rights reserved.

A musculoskeletal model of the elbow joint complex

NASA Technical Reports Server (NTRS)

Gonzalez, Roger V.; Barr, Ronald E.; Abraham, Lawrence D.

1993-01-01

This paper describes a musculoskeletal model that represents human elbow flexion-extension and forearm pronation-supination. Musculotendon parameters and the skeletal geometry were determined for the musculoskeletal model in the analysis of ballistic elbow joint complex movements. The key objective was to develop a computational model, guided by optimal control, to investigate the relationship among patterns of muscle excitation, individual muscle forces, and movement kinematics. The model was verified using experimental kinematic, torque, and electromyographic data from volunteer subjects performing both isometric and ballistic elbow joint complex movements. In general, the model predicted kinematic and muscle excitation patterns similar to what was experimentally measured.

Nerve injuries do occur in elbow arthroscopy.

PubMed

Hilgersom, Nick F J; van Deurzen, Derek F P; Gerritsma, Carina L E; van der Heide, Huub J L; Malessy, Martijn J A; Eygendaal, Denise; van den Bekerom, Michel P J

2018-01-01

The purpose is to create more awareness as well as emphasize the risk of permanent nerve injury as a complication of elbow arthroscopy. Patients who underwent elbow arthroscopy complicated by permanent nerve injury were retrospectively collected. Patients were collected using two strategies: (1) by word-of-mouth throughout the Dutch Society of Shoulder and Elbow Surgery, and the Leiden University Nerve Centre, and (2) approaching two medical liability insurance companies. Medical records were reviewed to determine patient characteristics, disease history and postoperative course. Surgical records were reviewed to determine surgical details. A total of eight patients were collected, four men and four women, ageing 21-54 years. In five out of eight patients (62.5%), the ulnar nerve was affected; in the remaining three patients (37.5%), the radial nerve was involved. Possible causes for nerve injury varied among patients, such as portal placement and the use of motorized instruments. A case series on permanent nerve injury as a complication of elbow arthroscopy is presented. Reporting on this sequel in the literature is little, however, its risk is not to be underestimated. This study emphasizes that permanent nerve injury is a complication of elbow arthroscopy, concurrently increasing awareness and thereby possibly aiding to prevention. IV, case series.

Characteristics of upper limb muscular strength in male wheelchair tennis players

PubMed Central

Moon, Hyo-Bin; Park, Seung-Jae; Kim, Al-Chan; Jang, Jee-Hun

2013-01-01

The purpose of this study was to identify the characteristics of muscular strength in upper limb and to present the preliminary information for development of sports injury prevention program and exercise rehabilitation program in wheelchair tennis players. Participants were 12 male wheelchair tennis players. Muscular strength was measured in shoulder and elbow joints with isokinetic dynamometer. Ipsilateral (IR) and bilateral (BR) balance ratio were calculated with isokinetic strength at 60°/sec. As a result, extension strength (ES) was significantly higher than flexion strength (FS) (P< 0.001), and IR in both sides and BR in ES were maintained within normal range whereas BR in FS was lower than normal range in shoulder joint. In elbow joint FS was significantly higher than ES (P< 0.05), and IR and BR were lower than normal range. Consequently, the different tendency in IR between shoulder and elbow joints and lower IR and BR in elbow joints could be the characteristics in male wheelchair tennis players. It is suggested that flexor strengthening program in nondominant shoulder joint, extensor strengthening program in both elbow joint, and flexor strengthening program in non-dominant elbow joint should be introduced for male wheelchair tennis players. PMID:24278887

Synergic co-activation of muscles in elbow flexion via fractional Brownian motion.

PubMed

Chang, Shyang; Hsyu, Ming-Chun; Cheng, Hsiu-Yao; Hsieh, Sheng-Hwu

2008-12-31

In reflex and volitional actions, co-activations of agonist and antagonist muscles are believed to be present. Recent studies indicate that such co-activations can be either synergic or dyssynergic. The aim of this paper is to investigate if the co-activations of biceps brachii, brachialis, and triceps brachii during volitional elbow flexion are in the synergic or dyssynergic state. In this study, two groups with each containing six healthy male volunteers participated. Each person of the first group performed 30 trials of volitional elbow flexion while each of the second group performed 30 trials of passive elbow flexion as control experiments. Based on the model of fractional Brownian motion, the intensity and frequency information of the surface electromyograms (EMGs) could be extracted simultaneously. No statistically significant changes were found in the control group. As to the other group, results indicated that the surface EMGs of all five muscle groups were temporally synchronized in frequencies with persistent intensities during each elbow flexion. In addition, the mean values of fractal dimensions for rest and volitional flexion states revealed significant differences with P < 0.01. The obtained positive results suggest that these muscle groups work together synergically to facilitate elbow flexion during the co-activations.

Treatment of elbow osteomyelitis with an interposition arthroplasty using a rectus abdominis free flap.

PubMed

Jaiswal, Rohit; Busse, Brittany; Allen, Robert; Sahar, David

2015-05-01

Osteomyelitis of the elbow may be a complex clinical problem. Treatment goals include the eradication of infection and preservation of maximal joint function. Bony debridement may be necessary in addition to elbow joint arthroplasty. The use of synthetic material or allograft as the arthroplasty material may be contraindicated in the setting of infection. The use of free muscle transfer as an arthroplasty medium has not been well described. A 22-year-old paraplegic man developed recurrent osteomyelitis of the right elbow, necessitating extensive bony debridement by the orthopedic surgery team. Reconstruction arthroplasty was performed using a free rectus abdominis muscle flap as the arthroplasty material to serve as a source of biologically active, well-vascularized arthroplasty medium in the presence of ongoing infection. A successful free muscle flap arthroplasty was performed. External fixation and physical therapy were implemented postoperatively. The patient had resolution of osteomyelitis and excellent functional use of the elbow for activities of daily living and wheelchair motion. Elbow arthroplasty in the setting of active infection may be accomplished by means of free tissue muscle transfer. Elimination of infection and acceptable joint function may be possible with this form of reconstruction.

Phenotypic disparity of the elbow joint in domestic dogs and wild carnivores.

PubMed

Figueirido, Borja

2018-05-16

In this article, I use geometric morphometrics in 2D from a sample of 366 elbow joints to quantify phenotypic disparity in domestic dog breeds, in wild canids, and across the order Carnivora. The elbow joint is a well-established morphological indicator of forearm motion and, by extension, of functional adaptations towards locomotor or predatory behavior in living carnivores. The study of the elbow joint in domestic dogs allows the exploration of potential convergences between (i) pursuit predators and fast-running dogs, and (ii) ambush predators and fighting breeds. The results indicate that elbow shape disparity among domestic dogs exceeds that in wolves; it is comparable to the disparity of wild Caninae, but is significantly lower than the one observed throughout Canidae and Carnivora. Moreover, fast-running and fighting breeds are not convergent in elbow joint shape with extreme pursuit and ambush wild carnivores, respectively. The role of artificial selection and developmental constraints in shaping limb phenotypic disparity through the extremely fast evolution of the domestic dog is discussed in the light of this new evidence. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Ultrasound shear wave elastography in the assessment of passive biceps brachii muscle stiffness: influences of sex and elbow position.

PubMed

Chen, Johnson; O'Dell, Michael; He, Wen; Du, Li-Juan; Li, Pai-Chi; Gao, Jing

To assess differences in biceps brachii muscle (BBM) stiffness as evaluated by ultrasound shear wave elastography (SWE). The passive stiffness of the BBM was quantified with shear wave velocity (SWV) measurements obtained from 10 healthy volunteers (5 men and 5 women, mean age 50years, age range 42-63 years) with the elbow at full extension and 30° flexion in this IRB-approved study. Potential differences between two depths within the muscle, two elbow positions, the two arms, and sexes were assessed by using two-tailed t-test. The reproducibility of SWV measurements was tested by using intraclass correlation coefficient (ICC). Significantly higher passive BBM stiffness was found at full elbow extension compared to 30° of flexion (p≤0.00006 for both arms). Significantly higher passive stiffness in women was seen for the right arm (p=0.04 for both elbow positions). Good correlation of shear wave velocity measured at the different depths. The ICC for interobserver and intraobserver variation was high. SWE is a reliable quantitative tool for assessing BBM stiffness, with differences in stiffness based on elbow position demonstrated and based on sex suggested. Copyright © 2017 Elsevier Inc. All rights reserved.

Prolonged phone-call posture causes changes of ulnar motor nerve conduction across elbow.

PubMed

Padua, Luca; Coraci, Daniele; Erra, Carmen; Doneddu, Pietro Emiliano; Granata, Giuseppe; Rossini, Paolo Maria

2016-08-01

Postures and work-hobby activities may play a role in the origin and progression of ulnar neuropathy at the elbow (UNE), whose occurrence appears to be increasing. The time spent on mobile-phone has increased in the last decades leading to an increased time spent with flexed elbow (prolonged-phone-posture, PPP). We aimed to assess the effect of PPP both in patients with symptoms of UNE and in symptom-free subjects. Patients with pure sensory symptoms of UNE and negative neurophysiological tests (MIN-UNE) and symptom-free subjects were enrolled. We evaluated ulnar motor nerve conduction velocity across elbow at baseline and after 6, 9, 12, 15, and 18min of PPP in both groups. Fifty-six symptom-free subjects and fifty-eight patients were enrolled. Globally 186 ulnar nerves from 114 subjects were studied. Conduction velocity of ulnar nerve across the elbow significantly changed over PPP time in patients with MIN-UNE, showing a different evolution between the two groups. PPP causes a modification of ulnar nerve functionality in patients with MIN-UNE. PPP may cause transient stress of ulnar nerve at elbow. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Manual handling methods evaluation based on oxygen consumption

NASA Astrophysics Data System (ADS)

Nurmianto, E.; Ciptomulyono, U.; Suparno; Kromodihardjo, S.; Setijono, H.; Arief, N. A.

2018-04-01

Mining industry has become one of the largest industries in Indonesia, now competing in billions dollar market, with numbers people employed. Deliveries of a Return Rolls (RR) involve the use of a hand truck and, in many cases, a shoulder/elbow-mode of carriage. Workers usually prefer to the Gendong (carrying on the small of the back or the hip, supported by the waist and arm) mode or Manggul (carrying on some stuff shoulder) mode, because they feel safer by carrying RR on the shoulder/elbow. In this study, the physiological workload involved in shoulder/elbow-mode carrying was investigated, especially focusing on the effects of load weight and inclination. To measure heart rate and oxygen uptake while carrying on the shoulder/elbow, a laboratory experiment was conducted and safety guidelines for such tasks were proposed, based on the experimental results. Four healthy male subjects performed shoulder/elbow-mode carrying, weight between 20 and 24 kg: (1) on inclination of 10o, (2) 20o and (3) 30o. The results showed that inclination involved an increased physiological burden, and that a load of 24 kg entailed a significantly higher physiological cost than carrying a load of 20 kg. Although shoulder/elbow-mode carrying has some advantages, the worker should be advised to carry a load of less than 20 kg, to avoid a high physiological load. During shoulder/elbow-mode carrying, it is also recommended that a person prepare more training in order to have muscular strength.

Determinants of shoulder and elbow flexion range: results from the San Antonio Longitudinal Study of Aging.

PubMed

Escalante, A; Lichtenstein, M J; Hazuda, H P

1999-08-01

To gain a knowledge of factors associated with impaired upper extremity range of motion (ROM) in order to understand pathways that lead to disability. Shoulder and elbow flexion range was measured in a cohort of 695 community-dwelling subjects aged 65 to 74 years. Associations between subjects' shoulder and elbow flexion ranges and their demographic and anthropometric characteristics, as well as the presence of diabetes mellitus or self-reported physician-diagnosed arthritis, were examined using multivariate regression models. The relationship between shoulder or elbow flexion range and subjects' functional reach was examined to explore the functional significance of ROM in these joints. The flexion range for the 4 joints studied was at least 120 degrees in nearly all subjects (> or = 99% of the subjects for each of the 4 joints). Multivariate models revealed significant associations between male sex, Mexican American ethnic background, the use of oral hypoglycemic drugs or insulin to treat diabetes mellitus, and a lower shoulder flexion range. A lower elbow flexion range was associated with male sex, increasing body mass index, and the use of oral hypoglycemic drugs or insulin. A higher shoulder or elbow flexion range was associated with a lower likelihood of having a short functional reach. The great majority of community-dwelling elderly have a flexion range of shoulder and elbow joints that can be considered functional. Diabetes mellitus and obesity are two potentially treatable factors associated with reduced flexion range of these two functionally important joints.

The Boyd–McLeod procedure for tennis elbow: mid- to long-term results

PubMed Central

Jeavons, Richard; Richards, Ian; Bayliss, Neil

2014-01-01

Background Tennis elbow is a common condition that usually responds to conservative measures. In refractory cases, surgical intervention is indicated. A plethora of surgical techniques have been described. We report the mid- to long-term outcomes of the Boyd–McLeod procedure for refractory tennis elbow. Methods A retrospective analysis and current review of patients that had undergone the Boyd–McLeod procedure over a 12-year period was undertaken. Demographics, time to discharge, length of follow-up and outcome scores were collected. Results Seventy patients underwent surgery. Mean time to discharge was 15.35 weeks, with 88% successful outcomes. Fifty-four patients were available for current follow-up at mean of 5.52 years (range 1.17 years to 11.49 years). Range of motion in all patients was unchanged. There were no revision procedures. Mean (SD) Mayo Elbow Performance Score was 90.85 (13.11), with 75.5% returning a good or excellent score and 24.5% a fair outcome. The mean (SD) Oxford Elbow Score was 44.04 (6.92); mean (SD) pain score was 89.5 (17.58); mean (SD) function score was 95.34 (9.59) and mean (SD) socio-psychological score was 91.50 (17.01). Overall, 83% of patients had an Oxford Elbow Score of 43 or greater, suggesting excellent outcome. Conclusions We show that the Boyd–McLeod procedure is an excellent option over both the short- and long-term for refractory tennis elbow. PMID:27582946

Open arthrolysis and prosthetic replacement of the radial head for elbow stiffness associated with rotation limitation.

PubMed

Liu, Shen; Liu, Jun-jian; Li, Xu-jun; Ruan, Hong-jiang; Fan, Cun-yi

2013-02-01

Limited forearm rotation is a frequent combined disorder in elbow stiffness. If the radial head cannot be saved during open arthrolysis, prosthetic replacement might be considered because it enhances stability and allows early motion. In this study we retrospectively analyzed the outcome of 8 patients (7 men, 1 woman) who underwent open arthrolysis and simultaneous prosthetic replacement after resection of the radial head to restore elbow range of motion and forearm rotation. Patients were a mean age of 31.7 years (range, 22-40 years). Postoperatively, the mean (range) active range of motion improved from 29.4° (0°-70°) to 113.1° (80°-135°), mean (range) supination increased from 38.8° (0°-80°) to 77.5° (50°-90°), and mean (range) pronation improved from 18.8° (0°-80°) to 68.8° (50°-80°). The Mayo Elbow Performance Score improved from a mean (range) of 57.5 (50-70) to 92.5 (85-100) points. No elbow valgus instability was detected over a mean duration of 26 months of follow-up. The implant was considered stable in all patients. Open arthrolysis and prosthetic replacement of the radial head are effective in treating elbow stiffness with associated rotation limitation after resection of the radial head. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

The Amount and Preferred Orientation of Simple-shear in a Deformation Tensor: Implications for Detecting Shear Zones and Faults with GPS

NASA Astrophysics Data System (ADS)

Johnson, A. M.; Griffiths, J. H.

2007-05-01

At the 2005 Fall Meeting of the American Geophysical Union, Griffiths and Johnson [2005] introduced a method of extracting from the deformation-gradient (and velocity-gradient) tensor the amount and preferred orientation of simple-shear associated with 2-D shear zones and faults. Noting the 2-D is important because the shear zones and faults in Griffiths and Johnson [2005] were assumed non-dilatant and infinitely long, ignoring the scissors- like action along strike associated with shear zones and faults of finite length. Because shear zones and faults can dilate (and contract) normal to their walls and can have a scissors-like action associated with twisting about an axis normal to their walls, the more general method of detecting simple-shear is introduced and called MODES "method of detecting simple-shear." MODES can thus extract from the deformation-gradient (and velocity- gradient) tensor the amount and preferred orientation of simple-shear associated with 3-D shear zones and faults near or far from the Earth's surface, providing improvements and extensions to existing analytical methods used in active tectonics studies, especially strain analysis and dislocation theory. The derivation of MODES is based on one definition and two assumptions: by definition, simple-shear deformation becomes localized in some way; by assumption, the twirl within the deformation-gradient (or the spin within the velocity-gradient) is due to a combination of simple-shear and twist, and coupled with the simple- shear and twist is a dilatation of the walls of shear zones and faults. The preferred orientation is thus the orientation of the plane containing the simple-shear and satisfying the mechanical and kinematical boundary conditions. Results from a MODES analysis are illustrated by means of a three-dimensional diagram, the cricket- ball, which is reminiscent of the seismologist's "beach ball." In this poster, we present the underlying theory of MODES and illustrate how it works by analyzing the three- dimensional displacements measured with the Global Positioning System across the 1999 Chi-Chi earthquake ground rupture in Taiwan. In contrast to the deformation zone in the upper several meters of the ground below the surface detected by Yu et al. [2001], MODES determines the orientation and direction of shift of a shear zone representing the earthquake fault within the upper several hundred or thousand meters of ground below the surface. Thus, one value of the MODES analysis in this case is to provide boundary conditions for dislocation solutions for the subsurface shape of the main rupture during the earthquake.

Effet Bauschinger lors de la plasticité cyclique de l'aluminium pur monocristallin

NASA Astrophysics Data System (ADS)

Alhamany, A.; Chicois, J.; Fougères, R.; Hamel, A.

1992-08-01

This paper is concerned with the study of microscopic mechanisms which control the cyclic deformation of pure aluminium and especially with the analysis of the Bauschinger effect which appears in aluminium single crystals deformed by cyclic straining. Fatigue tests are performed on Al single crystals with the crystal axis parallel to [ overline{1}23] at room temperature, at plastic shear strain amplitudes in the range from 10^{-4} to 3× 10^{-3}. Mechanical saturation is not obtained at any strain level. Instead, a hardening-softening-secondary hardening sequence is found. The magnitude of the Bauschinger effect as the difference between yield stresses in traction and in compression, changes all along the fatigue loop and during the fatigue test. The Bauschinger effect disappears at two points of the fatigue loop, one in the traction part, the other in the compression one. At these points, the Bauschinger effect is inverted. Dislocation arrangement evolutions with fatigue conditions can explain the cyclic behaviour of Al single crystals. An heterogeneous dislocation distribution can be observed in the cyclically strained metal : dislocation tangles, long dislocation walls and dislocation cell walls, separated by dislocation poor channels appear in the material as a function of the cycle number. The long range internal stress necessary to ensure the compatibility of deformation between the hard and soft regions controls the observed Bauschinger effect. Ce travail s'inscrit dans le cadre de l'étude des mécanismes microsocopiques intervenant lors de la déformation cyclique de l'aluminium pur et concerne en particulier l'analyse de l'effet Bauschinger apparaissant au cours de la solliciation cyclique des monocristaux. L'étude a été menée à température ambiante sur des monocristaux d'aluminium pur orientés pour un glissement simple (axe [ overline{1}23] ), à des amplitudes de déformation plastique comprise entre 10^{-4} et quelques 10^{-3}. Nous n'avons pas obtenu de véritable saturation mécanique. Nous sommes en présence d'une séquence durcissement-adoucissement-durcissement secondaire. L'amplitude de l'effet Bauschinger considéré comme la différence entre les limites élastiques en traction et en compression mesurées selon une procédure appropriée, évolue le long d'une boucle de fatigue, s'annule pour deux points particuliers l'un en traction l'autre en compression. De part et d'autre de ces points, le signe de l'effet Bauschinger est inversé. Les microstructures des états fatigués sont caractérisés par une répartition hétérogène des dislocations constituée d'amas, de murs ou des parois, suivant le degré de déformation cyclique, séparés par des zones à faible densité de dislocations. Les contraintes internes liées aux incompatibilités de déformation résultant de cette répartition hétérogène des dislocations sont à l'origine de l'effet Bauschinger observé dans les monocristaux. Ces contraintes et l'évolution de la quantité de cellules de dislocations avec la fatigue expliquent le durcissement secondaire.

Is digital photography an accurate and precise method for measuring range of motion of the shoulder and elbow?

PubMed

Russo, Russell R; Burn, Matthew B; Ismaily, Sabir K; Gerrie, Brayden J; Han, Shuyang; Alexander, Jerry; Lenherr, Christopher; Noble, Philip C; Harris, Joshua D; McCulloch, Patrick C

2018-03-01

Accurate measurements of shoulder and elbow motion are required for the management of musculoskeletal pathology. The purpose of this investigation was to compare three techniques for measuring motion. The authors hypothesized that digital photography would be equivalent in accuracy and show higher precision compared to the other two techniques. Using infrared motion capture analysis as the reference standard, shoulder flexion/abduction/internal rotation/external rotation and elbow flexion/extension were measured using visual estimation, goniometry, and digital photography on 10 fresh frozen cadavers. These measurements were performed by three physical therapists and three orthopaedic surgeons. Accuracy was defined by the difference from the reference standard (motion capture analysis), while precision was defined by the proportion of measurements within the authors' definition of clinical significance (10° for all motions except for elbow extension where 5° was used). Analysis of variance (ANOVA), t-tests, and chi-squared tests were used. Although statistically significant differences were found in measurement accuracy between the three techniques, none of these differences met the authors' definition of clinical significance. Precision of the measurements was significantly higher for both digital photography (shoulder abduction [93% vs. 74%, p < 0.001], shoulder internal rotation [97% vs. 83%, p = 0.001], and elbow flexion [93% vs. 65%, p < 0.001]) and goniometry (shoulder abduction [92% vs. 74%, p < 0.001] and shoulder internal rotation [94% vs. 83%, p = 0.008]) than visual estimation. Digital photography was more precise than goniometry for measurements of elbow flexion only [93% vs. 76%, p < 0.001]. There was no clinically significant difference in measurement accuracy between the three techniques for shoulder and elbow motion. Digital photography showed higher measurement precision compared to visual estimation for shoulder abduction, shoulder internal rotation, and elbow flexion. However, digital photography was only more precise than goniometry for measurements of elbow flexion. Overall digital photography shows equivalent accuracy to visual estimation and goniometry, but with higher precision than visual estimation. Copyright © 2017. Published by Elsevier B.V.

[A new kinematics method of determing elbow rotation axis and evaluation of its feasibility].

PubMed

Han, W; Song, J; Wang, G Z; Ding, H; Li, G S; Gong, M Q; Jiang, X Y; Wang, M Y

2016-04-18

To study a new positioning method of elbow external fixation rotation axis, and to evaluate its feasibility. Four normal adult volunteers and six Sawbone elbow models were brought into this experiment. The kinematic data of five elbow flexion were collected respectively by optical positioning system. The rotation axes of the elbow joints were fitted by the least square method. The kinematic data and fitting results were visually displayed. According to the fitting results, the average moving planes and rotation axes were calculated. Thus, the rotation axes of new kinematic methods were obtained. By using standard clinical methods, the entrance and exit points of rotation axes of six Sawbone elbow models were located under X-ray. And The kirschner wires were placed as the representatives of rotation axes using traditional positioning methods. Then, the entrance point deviation, the exit point deviation and the angle deviation of two kinds of located rotation axes were compared. As to the four volunteers, the indicators represented circular degree and coplanarity of elbow flexion movement trajectory of each volunteer were both about 1 mm. All the distance deviations of the moving axes to the average moving rotation axes of the five volunteers were less than 3 mm. All the angle deviations of the moving axes to the average moving rotation axes of the five volunteers were less than 5°. As to the six Sawbone models, the average entrance point deviations, the average exit point deviations and the average angle deviations of two different rotation axes determined by two kinds of located methods were respectively 1.697 2 mm, 1.838 3 mm and 1.321 7°. All the deviations were very small. They were all in an acceptable range of clinical practice. The values that represent circular degree and coplanarity of volunteer's elbow single curvature movement trajectory are very small. The result shows that the elbow single curvature movement can be regarded as the approximate fixed axis movement. The new method can replace the traditional method in accuracy. It can make up the deficiency of the traditional fixed axis method.

Tennis elbow

MedlinePlus

Epitrochlear bursitis; Lateral epicondylitis; Epicondylitis - lateral; Tendonitis - elbow ... Philadelphia, PA: Elsevier; 2017:chap 25. Biundo JJ. Bursitis, tendinitis, and other periarticular disorders and sports medicine. ...

Experimental study of plastic responses of pipe elbows

DOE Office of Scientific and Technical Information (OSTI.GOV)

Greenstreet, W.L.

Load-deflection responses were determined experimentally for sixteen 152.4-mm (6-in.) (nominal) commercial carbon steel pipe elbows and four 152.4-mm (6-in.) stainless steel elbows. Each specimen was loaded with an external force of sufficient magnitude to produce predominantly plastic response. The influences of bend radius and wall thickness were studied, as well as the effect of internal prssure on load-deflection behavior. Comparisons of results from stainless steel and from carbon steel elbows indicate differences in responses attributable to material differences. The results were interpreted in terms of limit analysis concepts, and collapse loads were determined. Trends given by the collapse loads aremore » identified and discussed.« less

Mechanical solution for a mechanical problem: Tennis elbow.

PubMed

Rothschild, Bruce

2013-07-18

Lateral epicondylitis is a relatively common clinical problem, easily recognized on palpation of the lateral protuberance on the elbow. Despite the "itis" suffix, it is not an inflammatory process. Therapeutic approaches with topical non-steroidal anti-inflammatory drugs, corticosteroids and anesthetics have limited benefit, as would be expected if inflammation is not involved. Other approaches have included provision of healing cytokines from blood products or stem cells, based on the recognition that this repetitive effort-derived disorder represents injury. Noting calcification/ossification of tendon attachments to the lateral epicondyle (enthesitis), dry needling, radiofrequency, shock wave treatments and surgical approaches have also been pursued. Physiologic approaches, including manipulation, therapeutic ultrasound, phonophoresis, iontophoresis, acupuncture and exposure of the area to low level laser light, has also had limited success. This contrasts with the benefit of a simple mechanical intervention, reducing the stress on the attachment area. This is based on displacement of the stress by use of a thin (3/4-1 inch) band applied just distal to the epicondyle. Thin bands are required, as thick bands (e.g., 2-3 inch wide) simply reduce muscle strength, without significantly reducing stress. This approach appears to be associated with a failure rate less than 1%, assuming the afflicted individual modifies the activity that repeatedly stresses the epicondylar attachments.

Mechanical solution for a mechanical problem: Tennis elbow

PubMed Central

Rothschild, Bruce

2013-01-01

Lateral epicondylitis is a relatively common clinical problem, easily recognized on palpation of the lateral protuberance on the elbow. Despite the “itis” suffix, it is not an inflammatory process. Therapeutic approaches with topical non-steroidal anti-inflammatory drugs, corticosteroids and anesthetics have limited benefit, as would be expected if inflammation is not involved. Other approaches have included provision of healing cytokines from blood products or stem cells, based on the recognition that this repetitive effort-derived disorder represents injury. Noting calcification/ossification of tendon attachments to the lateral epicondyle (enthesitis), dry needling, radiofrequency, shock wave treatments and surgical approaches have also been pursued. Physiologic approaches, including manipulation, therapeutic ultrasound, phonophoresis, iontophoresis, acupuncture and exposure of the area to low level laser light, has also had limited success. This contrasts with the benefit of a simple mechanical intervention, reducing the stress on the attachment area. This is based on displacement of the stress by use of a thin (3/4-1 inch) band applied just distal to the epicondyle. Thin bands are required, as thick bands (e.g., 2-3 inch wide) simply reduce muscle strength, without significantly reducing stress. This approach appears to be associated with a failure rate less than 1%, assuming the afflicted individual modifies the activity that repeatedly stresses the epicondylar attachments. PMID:23878775

Improved CHESS imaging with the use of rice pads: Investigation in the neck, shoulder, and elbow.

PubMed

Moriya, Susumu; Miki, Yukio; Yokobayashi, Tsuneo; Yamamoto, Akira; Kanagaki, Mitsunori; Komori, Yoshiaki; Fujimoto, Koji; Ishikawa, Mitsunori

2010-06-01

To investigate the feasibility of rice pads for improving nonuniform fat suppression in magnetic resonance imaging (MRI) of the neck, shoulder, and elbow using the chemical shift selective (CHESS) technique. CHESS imaging of the neck, shoulder, and elbow was performed on 10 healthy volunteers with and without the use of rice pads. Images were visually assessed by one radiologist and one radiologic technologist using a four-point scale. Results were compared using Wilcoxon's signed rank sum test. Images with and without rice pads were rated 3.9 and 1.5 for the neck (P = 0.002), 3.85 and 2.5 for the shoulder (P = 0.002), and 3.4 and 2.45 for the elbow (P = 0.004). Fat-suppressed images obtained using the CHESS technique were significantly improved by rice pads for the neck, shoulder, and elbow, indicating that image deterioration with CHESS caused by magnetic field nonuniformity can be improved by rice pads in all body areas.

Acute effects of one session dry needling on a chronic golfer’s elbow disability

PubMed Central

Shariat, Ardalan; Noormohammadpour, Pardis; Memari, Amir Hossein; Ansari, Noureddin Nakhostin; Cleland, Joshua A.; Kordi, Ramin

2018-01-01

A 40-year-old retired male elite athlete with more than 20 years’ experience in wrestling and bodybuilding with mild elbow pain and disability of 2 years presented to our clinic reporting an acute pain in medial aspect of the elbow. Physical examination revealed symptoms of left Golfer’s elbow during target-directed movements. The results of sonography in left elbow showed low level of hypo echo irregularity and increased blood flow in color Doppler mode in the common flexor origin. The pain amplitude was moderate at rest and extremely high during kinetic and intentional movements. During last 2 years, the patient tried different types of therapy including manual therapy, Transcutaneous electrical nerve stimulation and also received a variety of injections none of which were effective for reducing pain and disability. This is the first study showed that one sessions of dry needling improved both pain and disability and helped to return to a normal life and exercise training. PMID:29511665

[Imaging of the elbow joint with focus MRI. Part 2: muscles, nerves and synovial membranes].

PubMed

Rehm, J; Zeifang, F; Weber, M-A

2014-03-01

This review article discusses the magnetic resonance imaging (MRI) features and pathological changes of muscles, nerves and the synovial lining of the elbow joint. Typical imaging findings are illustrated and discussed. In addition, the cross-sectional anatomy and anatomical variants, such as accessory muscles and plicae are discussed. Injuries of the muscles surrounding the elbow joint, as well as chronic irritation are particularly common in athletes. Morphological changes in MRI, for example tennis or golfer's elbow are typical and often groundbreaking. By adapting the examination sequences, imaging planes and slices, complete and incomplete tendon ruptures can be reliably diagnosed. Although the clinical and electrophysiological examinations form the basis for the diagnosis of peripheral neuropathies, MRI provides useful additional information about the precise localization due to its high resolution and good soft tissue contrast and helps to rule out differential diagnoses. Synovial diseases, such as inflammatory arthritis, proliferative diseases and also impinging plicae must be considered in the MRI diagnostics of the elbow joint.

Rehabilitation of the Overhead Athlete’s Elbow

PubMed Central

Wilk, Kevin E.; Macrina, Leonard C.; Cain, E. Lyle; Dugas, Jeffrey R.; Andrews, James R.

2012-01-01

The activities required during overhead sports, particularly during baseball pitching, produce large forces at the elbow joint. Injuries to the elbow joint frequently occur in the overhead athlete because of the large amount of forces observed during the act of throwing, playing tennis, or playing golf. Injuries may result because of repetitive overuse, leading to tissue failure. Rehabilitation following injury or surgery to the throwing elbow is vital to fully restore normal function and return the athlete to competition as quickly and safely as possible. Rehabilitation of the elbow, whether following injury or postsurgical, must follow a progressive and sequential order, building on the previous phase, to ensure that healing tissues are not compromised. Emphasis is placed on restoring full motion, muscular strength, and neuromuscular control while gradually applying loads to healing tissue. In addition, when one is creating a rehabilitation plan for athletes, it is imperative to treat the entire upper extremity, core, and legs to create and dissipate the forces generated at each joint. PMID:23016113

The role of total elbow arthroplasty in traumatology.

PubMed

Mansat, P; Bonnevialle, N; Rongières, M; Bonnevialle, P

2014-10-01

Fractures of the distal humerus account for 5% of osteoporotic fractures in subjects older than 60 years. A history of osteoporosis, co-morbidities, and joint comminution make their management difficult. The therapeutic options are limited to functional treatments, osteosynthesis, or either partial or total arthroplasty. Functional treatment of distal humerus fractures in the elderly subject provide inconsistent results, often with persistence of pain with a stiff or unstable elbow. Osteosynthesis remains the reference treatment for these fractures, following the principle of stable and rigid osteosynthesis allowing early mobilization. However, joint comminution and a history of osteoporosis occasionally make it impossible to meet this objective, with a considerable rate of complications and surgical revisions. Total elbow arthroplasty remains an alternative to osteosynthesis with very satisfactory immediate results restoring a painless, stable, and functional elbow. These results seem reproducible and sustainable over time. The complication rate is not uncommon with an approximately 10% surgical revision rate. Elbow hemiarthroplasty remains to be validated in this indication. V. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Arthroscopic management of the painful total elbow arthroplasty.

PubMed

Phadnis, Joideep; Bain, Gregory I

2016-01-01

Failure of total elbow arthroplasty is more common than after other major joint arthroplasties and is often a result of aseptic loosening, peri-prosthetic infection, fracture and instability. Infection can be a devastating complication, yet there are no established guidelines for the pre-operative diagnosis of total elbow peri-prosthetic infection. This is because pre-operative clinical, radiographic and biochemical tests are often unreliable. Using three case examples, a standardized protocol for the clinical and arthroscopic assessment of the painful total elbow arthroplasty is described. This is used to provide a mechanical and microbiological diagnosis of the patient's pain. There have been no complications resulting from the use of this technique in the three patients described, nor in any other patient to date. The staged protocol described in the present study, utilizing arthroscopic assessment, has refined the approach to the painful total elbow arthroplasty because it directly influences the definitive surgical management of the patient. It is recommended that other surgeons follow the principles outlined in the present study when faced with this challenging problem.

The Effects of a Functional Elbow Brace on Medial Joint Stability: A Case Study

PubMed Central

Pincivero, Danny M.; Rijke, Arie M.; Heinrichs, Kristinn; Perrin, David H.

1994-01-01

Medical elbow ligament sprains in athletics can be traumatic and disabling. In this case report, we outline the effect of a prototype functional elbow brace on joint stability in a female collegiate javelin thrower with an ulnar collateral ligament sprain. A valgus force to both elbows was applied using graded stress radiography (Telos GA-II/E stress device) at 0, 5, 10, and 15 kiloPascals (kPa) of pressure. The increase in gap width between the coronoid process and the medial epicondyle was measured from anteroposterior radiographs to determine medial displacement. The brace resulted in less displacement in both injured and noninjured ulnar collateral ligament; injured ulnar collateral ligament demonstrated greater displacement regardless of condition. The brace restored medial stability to the elbow joint by 49%, 38%, and 35% at 5, 10, and 15 kPa of pressure, respectively. The application of the brace may be useful in athletes with ulnar collateral ligament injuries. ImagesFig 1Fig 2 PMID:16558285

Bipolar Transfer of Latissimus Dorsi Myocutaneous Flap for Restoration of Elbow Flexion in Late Traumatic Brachial Plexus Injury: Evaluation of 13 Cases.

PubMed

Azab, Ahmed Abo-Hashem; Alsabbahi, Mohammad Salah

2017-02-01

Restoration of elbow flexion following traumatic brachial plexus injury represents a great challenge to the reconstructive surgeons. Functional muscle transfers come next to the sophisticated types of nerve surgery in this area. Many transfers are well known for restoration of elbow flexion; bipolar or unipolar latissimus dorsi, triceps brachii, sternocleidomastoid, pectoralis major, and Steindler flexorplasty. Evaluation of the outcome of bipolar transfer of latissimus dorsi myocutaneous flap when used to restore elbow flexion in late traumatic brachial plexus injury. Thirteen patients were included in this case series with careful evaluation both preoperatively and postoperatively both clinically and using electromyography. Almost 84.6% of patients (11 of 13) developed G3-4 on the Medical Research Council grading with relatively minimal both donor-site and recipient-site morbidity. Bipolar transfer of latissimus dorsi myocutaneous flap is a reliable method for restoration of elbow flexion in patients suffering from late sequelae of traumatic brachial plexus injury.

General Halleck's itchy elbows.

PubMed

Cropley, Thomas G

2007-01-01

General Henry Wager Halleck served as general-in-chief and chief of staff of the Federal army from 1862-1865. Unpopular with troops as well as with many members of the Lincoln administration, he was a particular source of irritation to Secretary of Navy Gideon Welles. In his posthumously-published diary of the war years, Welles viciously criticized Halleck for his failings as army commander. Welles also derided Halleck's personality and personal appearance. Welles found the general's habitual elbow-scratching annoying enough to mention it in five separate diary entries. This depiction of Halleck ceaselessly, nervously scratching his elbows has entered Civil War folklore. Why did Halleck scratch his elbows? Two possibilities exist. Either he did so compulsively, as a nervous habit, or he was scratching an itch. In this paper, I present a speculative argument that Halleck may have had a skin disease, possibly atopic dermatitis, and that this may have contributed to or have been the sole cause of his elbow scratching.

Phrenic Nerve Transfer for Reconstruction of Elbow Extension in Severe Brachial Plexus Injuries.

PubMed

Flores, Leandro P; Socolovsky, Mariano

2016-09-01

Background Restoring elbow extension is an important objective to pursue when repairing the brachial plexus in patients with a flail arm. Based upon the good results obtained using the phrenic nerve to restore elbow flexion and shoulder stability, we hypothesized that this nerve could also be employed to reconstruct elbow extension in patients with severe brachial plexus injuries. Methods A retrospective study of 10 patients in which the phrenic nerve targeted the radial nerve (7 patients) or the branch to the long head of the triceps (3 patients) as a surgical strategy for reconstruction of the brachial plexus. Results The mean postoperative follow-up time was 34 months. At final follow-up, elbow extension graded as M4 was measured in three patients, Medical Research Council MRC M3 in five patients, and M2 in one patient, while one patient experienced no measurable recovery (M0). No patient complained or demonstrated any signs of respiratory insufficiency postoperatively. Conclusions The phrenic nerve is a reliable donor for reanimation of elbow extension in such cases, and the branch to the long head of the triceps should be considered as a better target for the nerve transfer. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Voluntary activation of biceps-to-triceps and deltoid-to-triceps transfers in quadriplegia.

PubMed

Peterson, Carrie L; Bednar, Michael S; Bryden, Anne M; Keith, Michael W; Perreault, Eric J; Murray, Wendy M

2017-01-01

The biceps or the posterior deltoid can be transferred to improve elbow extension function for many individuals with C5 or C6 quadriplegia. Maximum strength after elbow reconstruction is variable; the patient's ability to voluntarily activate the transferred muscle to extend the elbow may contribute to the variability. We compared voluntary activation during maximum isometric elbow extension following biceps transfer (n = 5) and deltoid transfer (n = 6) in three functional postures. Voluntary activation was computed as the elbow extension moment generated during maximum voluntary effort divided by the moment generated with full activation, which was estimated via electrical stimulation. Voluntary activation was on average 96% after biceps transfer and not affected by posture. Individuals with deltoid transfer demonstrated deficits in voluntary activation, which differed by posture (80% in horizontal plane, 69% in overhead reach, and 70% in weight-relief), suggesting inadequate motor re-education after deltoid transfer. Overall, individuals with a biceps transfer better activated their transferred muscle than those with a deltoid transfer. This difference in neural control augmented the greater force-generating capacity of the biceps leading to increased elbow extension strength after biceps transfer (average 9.37 N-m across postures) relative to deltoid transfer (average 2.76 N-m across postures) in our study cohort.

Voluntary activation of biceps-to-triceps and deltoid-to-triceps transfers in quadriplegia

PubMed Central

Peterson, Carrie L.; Bednar, Michael S.; Bryden, Anne M.; Keith, Michael W.; Perreault, Eric J.; Murray, Wendy M.

2017-01-01

The biceps or the posterior deltoid can be transferred to improve elbow extension function for many individuals with C5 or C6 quadriplegia. Maximum strength after elbow reconstruction is variable; the patient’s ability to voluntarily activate the transferred muscle to extend the elbow may contribute to the variability. We compared voluntary activation during maximum isometric elbow extension following biceps transfer (n = 5) and deltoid transfer (n = 6) in three functional postures. Voluntary activation was computed as the elbow extension moment generated during maximum voluntary effort divided by the moment generated with full activation, which was estimated via electrical stimulation. Voluntary activation was on average 96% after biceps transfer and not affected by posture. Individuals with deltoid transfer demonstrated deficits in voluntary activation, which differed by posture (80% in horizontal plane, 69% in overhead reach, and 70% in weight-relief), suggesting inadequate motor re-education after deltoid transfer. Overall, individuals with a biceps transfer better activated their transferred muscle than those with a deltoid transfer. This difference in neural control augmented the greater force-generating capacity of the biceps leading to increased elbow extension strength after biceps transfer (average 9.37 N-m across postures) relative to deltoid transfer (average 2.76 N-m across postures) in our study cohort. PMID:28253262

Assessing the therapeutic effect of 625-nm light-emitting diodes

NASA Astrophysics Data System (ADS)

Mao, Zongzhen; Xu, Guodong; Yang, Yi

2014-09-01

To evaluate the effects of red Light-Emitting Diodes on elbow extensor and flexor strength and the recovery of exercise induced fatigue, the torque values from the isokinetic dynamometer as well as biochemistry parameters were used as outcome measures. A randomized double-blind placebo-controlled crossover trial was performed with twenty male young tennis athletes. Active LED therapy (LEDT, with wavelength 625nm, 10 minutes total irradiation time, irradiated area amount to 30cm2, and 900J of total energy irradiated) or an identical placebo was delivered under double-blinded conditions to the left elbow just before exercise. The isokinetic muscle strength was measured immediately after irradiation. The blood lactate levels were sampled pre-exercise and post-exercise. The peak torque values of elbow extensor strength were significantly different between two groups. As in elbow flexor strength, the difference of peak torque was not significant. The blood lactate concentration of LEDT group post-exercise was significantly lower than those of placebo group. The results indicate that 625nm LED therapy is effective in preventing muscle fatigue as it can significantly reduce peak torque value of elbow extensors and blood lactate concentration. It has no effect on the strength of left elbow flexor or backhand performance in tennis.

Arthroscopic resection of humeroradial synovial plica for persistent lateral elbow pain.

PubMed

Rajeev, Aysha; Pooley, Joesph

2015-04-01

To review the outcome of 121 patients who underwent arthroscopic resection of a humeroradial synovial plica for persistent lateral elbow pain. 92 men and 29 women aged 24 to 56 (mean, 38) years with chronic lateral elbow pain underwent arthroscopic resection of a humeroradial synovial plica using a motorised soft tissue shaver, followed by intensive physiotherapy. The modified elbow score and range of motion were assessed, as were wound healing, infection, soft tissue swelling or effusion, tenderness, ligamentous instability, and motor strength. No patient had any ligamentous instability. 80 patients were pain-free at 3 months; only 3 patients were taking pain medication at 6 months. All patients had full pronation and supination; the mean range of motion was 3º to 135º of flexion. The mean modified elbow score at 12 months was 93.2 (range, 72-100). The percentages of patients with excellent, good, fair, and poor score were 70%, 17%, 8%, and 5% at 3 months, 74%, 20%, 3%, and 3% at 6 months, and 76%, 18%, 3%, and 3% at 12 months, respectively. A humeroradial synovial plica is one of the causes of chronic lateral elbow pain. Arthroscopic resection of the synovial plica followed by intensive physiotherapy achieved good outcome.

Visualization of 3D elbow kinematics using reconstructed bony surfaces

NASA Astrophysics Data System (ADS)

Lalone, Emily A.; McDonald, Colin P.; Ferreira, Louis M.; Peters, Terry M.; King, Graham J. W.; Johnson, James A.

2010-02-01

An approach for direct visualization of continuous three-dimensional elbow kinematics using reconstructed surfaces has been developed. Simulation of valgus motion was achieved in five cadaveric specimens using an upper arm simulator. Direct visualization of the motion of the ulna and humerus at the ulnohumeral joint was obtained using a contact based registration technique. Employing fiducial markers, the rendered humerus and ulna were positioned according to the simulated motion. The specific aim of this study was to investigate the effect of radial head arthroplasty on restoring elbow joint stability after radial head excision. The position of the ulna and humerus was visualized for the intact elbow and following radial head excision and replacement. Visualization of the registered humerus/ulna indicated an increase in valgus angulation of the ulna with respect to the humerus after radial head excision. This increase in valgus angulation was restored to that of an elbow with a native radial head following radial head arthroplasty. These findings were consistent with previous studies investigating elbow joint stability following radial head excision and arthroplasty. The current technique was able to visualize a change in ulnar position in a single DoF. Using this approach, the coupled motion of ulna undergoing motion in all 6 degrees-of-freedom can also be visualized.

Biomechanics principle of elbow joint for transhumeral prostheses: comparison of normal hand, body-powered, myoelectric & air splint prostheses.

PubMed

Abd Razak, Nasrul Anuar; Abu Osman, Noor Azuan; Gholizadeh, Hossein; Ali, Sadeeq

2014-09-10

Understanding of kinematics force applied at the elbow is important in many fields, including biomechanics, biomedical engineering and rehabilitation. This paper provides a comparison of a mathematical model of elbow joint using three different types of prosthetics for transhumeral user, and characterizes the forces required to overcome the passive mechanical of the prosthetics at the residual limb. The study modeled the elbow as a universal joint with intersecting axes of x-axis and y-axis in a plain of upper arm and lower arm. The equations of force applied, torque, weight and length of different type of prosthetics and the anthropometry of prosthetics hand are discussed in this study. The study also compares the force, torque and pressure while using all three types of prosthetics with the normal hand. The result was measured from the elbow kinematics of seven amputees, using three different types of prosthetics. The F-Scan sensor used in the study is to determine the pressure applied at the residual limb while wearing different type of prostheses. These technological advances in assessment the biomechanics of an elbow joint for three different type of prosthetics with the normal hand bring the new information for the amputees and prosthetist to choose the most suitable device to be worn daily.

Reconstruction of the elbow and forearm for Ewing sarcoma of ulna: A new biological technique

PubMed Central

Puri, Ajay; Gulia, Ashish; Byregowda, Suman; Ramanujan, Vishnu

2016-01-01

Primary bone tumors around the elbow represent <1% of all the skeletal tumors. Surgery with or without adjuvant therapy (radiotherapy, chemotherapy) is the treatment of choice for malignant tumors. Reconstruction of the elbow and forearm in malignant tumors is challenging as it involves a complex interplay between multiple joints which need to be stabilized for the optimal functional outcome. We describe a new technique for the reconstruction of the elbow after resection of a proximal ulna tumor with articular radio-ulnar synostosis with the creation of a single bone forearm. We attempted to achieve a mobile elbow and stable wrist joint with the radio-ulnar union at the proximal articular surface of the ulna resulting in a single bone forearm. The procedure involves an oblique osteotomy preserving the olecranon process (after taking adequate margins based on oncological principles) and its articular cartilage along with the attachment of the triceps tendon. Then the radial head was partially denuded of its cartilage using a burr, leaving cartilage only on the volar side, and then fused to the remnant olecranon. Osteosynthesis was done using compression screw and tension band wiring. The advantages of this procedure are that the mobility at wrist and elbow are retained, it requires minimal hardware and allows for primary closure of the wound. PMID:27186061

Elbow joint adductor moment arm as an indicator of forelimb posture in extinct quadrupedal tetrapods

PubMed Central

Fujiwara, Shin-ichi; Hutchinson, John R.

2012-01-01

Forelimb posture has been a controversial aspect of reconstructing locomotor behaviour in extinct quadrupedal tetrapods. This is partly owing to the qualitative and subjective nature of typical methods, which focus on bony articulations that are often ambiguous and unvalidated postural indicators. Here we outline a new, quantitatively based forelimb posture index that is applicable to a majority of extant tetrapods. By determining the degree of elbow joint adduction/abduction mobility in several tetrapods, the carpal flexor muscles were determined to also play a role as elbow adductors. Such adduction may play a major role during the stance phase in sprawling postures. This role is different from those of upright/sagittal and sloth-like creeping postures, which, respectively, depend more on elbow extensors and flexors. Our measurements of elbow muscle moment arms in 318 extant tetrapod skeletons (Lissamphibia, Synapsida and Reptilia: 33 major clades and 263 genera) revealed that sprawling, sagittal and creeping tetrapods, respectively, emphasize elbow adductor, extensor and flexor muscles. Furthermore, scansorial and non-scansorial taxa, respectively, emphasize flexors and extensors. Thus, forelimb postures of extinct tetrapods can be qualitatively classified based on our quantitative index. Using this method, we find that Triceratops (Ceratopsidae), Anhanguera (Pterosauria) and desmostylian mammals are categorized as upright/sagittally locomoting taxa. PMID:22357261

Delayed repair of distal biceps tendon ruptures is successful: a case-control study.

PubMed

Haverstock, John; Grewal, Ruby; King, Graham J W; Athwal, George S

2017-06-01

The literature has shown an increased complication rate with a delay to surgical repair of acute distal biceps tendon ruptures; however, little has been documented regarding the outcome of delayed repairs. This case-control study compared a study cohort of delayed (>21 days) distal biceps tendon repairs with a control cohort repaired acutely (<21 days). Sixteen delayed repair cases were reviewed and matched with acute controls (1:3) based on repair technique, age, and workers' compensation status. The delayed cohort was reviewed and completed isometric strength testing and the Disabilities of the Arm, Shoulder and Hand questionnaire; Patient-Rated Elbow Evaluation; and American Shoulder and Elbow Surgeons elbow questionnaire. The time to surgery averaged 37 ± 12 days in the delayed cohort versus 10 ± 6 days in the acute cohort. Complications occurred in 63% of patients in the delayed cohort versus 29% in the acute cohort (P = .04); however, 90% of the delayed cohort's complications consisted of transient paresthesias. Follow-up scores on the Patient-Rated Elbow Evaluation, Disabilities of the Arm, Shoulder and Hand questionnaire, and American Shoulder and Elbow Surgeons elbow questionnaire were not statistically different between cohorts (P > .37, P > .22, and P > .46, respectively). Despite a high rate of initial complications, patients treated with distal biceps tendon repair after a delay (>21 days) can expect similar functional outcomes to those treated acutely. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Corticosteroid and platelet-rich plasma injection therapy in tennis elbow (lateral epicondylalgia): a survey of current U.K. specialist practice and a call for clinical guidelines.

PubMed

Titchener, Andrew G; Booker, Simon J; Bhamber, Nivraj S; Tambe, Amol A; Clark, David I

2015-11-01

Tennis elbow is a common condition with a variety of treatment options, but little is known about which of these options specialists choose most commonly. Corticosteroid injections in tennis elbow may reduce pain in the short-term but delay long-term recovery. We have undertaken a UK-wide survey of upper limb specialists to assess current practice. Cross-sectional electronic survey of current members of the British Elbow and Shoulder Society (BESS) and the British Society for Surgery of the Hand (BSSH). 271 of 1047 eligible members responded (25.9%); consultant surgeons constituted the largest group (232/271, 85%). 131 respondents (48%) use corticosteroid injections as their first-line treatment for tennis elbow. 206 respondents (77%) believed that corticosteroid injections are not potentially harmful in the treatment of tennis elbow, while 31 (11%) did not use them in their current practice. In light of recent evidence of the potential harmful effects of corticosteroid therapy, 136 (50%) had not changed their practice while 108 (40.1%) had reduced or discontinued their use. 43 respondents (16%) reported having used platelet-rich plasma injections. Recent high-quality evidence that corticosteroids may delay recovery in tennis elbow appears to have had a limited effect on current practice. Treatment is not uniform among specialists and a proportion of them use platelet-rich plasma injections. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Monitoring Hip and Elbow Dysplasia achieved modest genetic improvement of 74 dog breeds over 40 years in USA.

PubMed

Hou, Yali; Wang, Yachun; Lu, Xuemei; Zhang, Xu; Zhao, Qian; Todhunter, Rory J; Zhang, Zhiwu

2013-01-01

Hip (HD) and Elbow Dysplasia (ED) are two common complex developmental disorders of dogs. In order to decrease their prevalence and severity, the Orthopedic Foundation for Animals (OFA) has a voluntary registry of canine hip and elbow conformation certified by boarded radiologists. However, the voluntarily reports have been severely biased against exposing dogs with problems, especially at beginning period. Fluctuated by additional influential factors such as age, the published raw scores barely showed trends of improvement. In this study, we used multiple-trait mixed model to simultaneously adjust these factors and incorporate pedigree to derive Estimated Breeding Values (EBV). A total of 1,264,422 dogs from 74 breeds were evaluated for EBVs from 760,455 hip scores and 135,409 elbow scores. These EBVs have substantially recovered the reporting bias and the other influences. Clear and steady trends of genetic improvement were observed over the 40 years since 1970. The total genetic improvements were 16.4% and 1.1% of the phenotypic standard deviation for HD and ED, respectively. The incidences of dysplasia were 0.83% and 2.08%, and the heritabilities were estimated as 0.22 and 0.17 for hip and elbow scores, respectively. The genetic correlation between them was 0.12. We conclude that EBV is more effective than reporting raw phenotype. The weak genetic correlation suggested that selection based on hip scores would also slightly improve elbow scores but it is necessary to allocate effort toward improvement of elbow scores alone.

Monitoring Hip and Elbow Dysplasia Achieved Modest Genetic Improvement of 74 Dog Breeds over 40 Years in USA

PubMed Central

Zhang, Xu; Zhao, Qian; Todhunter, Rory J.; Zhang, Zhiwu

2013-01-01

Hip (HD) and Elbow Dysplasia (ED) are two common complex developmental disorders of dogs. In order to decrease their prevalence and severity, the Orthopedic Foundation for Animals (OFA) has a voluntary registry of canine hip and elbow conformation certified by boarded radiologists. However, the voluntarily reports have been severely biased against exposing dogs with problems, especially at beginning period. Fluctuated by additional influential factors such as age, the published raw scores barely showed trends of improvement. In this study, we used multiple-trait mixed model to simultaneously adjust these factors and incorporate pedigree to derive Estimated Breeding Values (EBV). A total of 1,264,422 dogs from 74 breeds were evaluated for EBVs from 760,455 hip scores and 135,409 elbow scores. These EBVs have substantially recovered the reporting bias and the other influences. Clear and steady trends of genetic improvement were observed over the 40 years since 1970. The total genetic improvements were 16.4% and 1.1% of the phenotypic standard deviation for HD and ED, respectively. The incidences of dysplasia were 0.83% and 2.08%, and the heritabilities were estimated as 0.22 and 0.17 for hip and elbow scores, respectively. The genetic correlation between them was 0.12. We conclude that EBV is more effective than reporting raw phenotype. The weak genetic correlation suggested that selection based on hip scores would also slightly improve elbow scores but it is necessary to allocate effort toward improvement of elbow scores alone. PMID:24124555

Capitellar Erosion after Radial Head Arthroplasty: A Comparative Biomechanical Study of Operated Radial Head Fractures on Cadaveric Specimens.

PubMed

Chytas, I D; Antonopoulos, C; Cheva, A; Givissis, P

2018-03-23

We asked whether either open reduction and internal fixation (ORIF) or radial head arthroplasty (RHA), common techniques used for the confrontation of displaced or comminuted radial head fractures, are correlated with cartilage wear of the capitulum. We hypothesized that neither ORIF nor RHA are correlated with capitellar cartilage wear. On 5 cadaveric elbow specimens, osteotomies were employed to simulate radial head comminuted fractures followed with ORIF by Herbert screws. Radial heads were also excised from other 5 cadaveric elbow specimens and were replaced by metallic monopolar implants. Finally 2 elbows were not operated and used as a control group. Custom-made rotary machines, working unstoppably, generated 700.000 pronation and supination forearm movements at an 110° arc of motion. The elbow joints were examined with pre- and postoperative Magnetic Resonance Imaging (MRI) scans and the articular surfaces of the capitula were resected and sent for histopathology study. In the 2 cadaveric elbows of the control group and the 4 elbows treated with ORIF no cartilage damage was found. The fifth one displayed cartilage fissures which were classified according to International Cartilage Repair Society (ICRS) grading system as grade I cartilage damage. On the contrary, all 5 elbows treated with RHA sustained complete cartilage loss, exposure of the subchondral bone and were classified as ICRS grade IV cartilage damage. Our study suggests that metallic monopolar RHA after a displaced or comminuted radial head fracture carries a high risk of rapidly evolving cartilage loss of the capitulum. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

In vivo three-dimensional elbow biomechanics during forearm rotation.

PubMed

Omori, Shinsuke; Miyake, Junichi; Oka, Kunihiro; Tanaka, Hiroyuki; Yoshikawa, Hideki; Murase, Tsuyoshi

2016-01-01

It is unclear how elbow kinematics changes during forearm rotation. This study investigated in vivo 3-dimensional elbow kinematics during forearm rotation. We studied 12 normal elbows using in vivo 3-dimensional computed tomography data in maximum forearm supination, neutral, and maximum pronation with the elbows in extension. We measured the motion of the radius and ulna relative to the humerus using a markerless bone registration technique and the contact area of the radiocapitellar joint, proximal radioulnar joint, and ulnohumeral joint using a proximity mapping method. When the forearm rotated from the supinated position to the pronated position, the radius showed significant varus rotation, internal rotation, and extension relative to the humerus. The center of the radial head significantly translated anteriorly, proximally, and laterally. The ulna significantly rotated in valgus, and the deepest point on the sagittal ridge of the trochlear notch translated medially with forearm pronation. The contact area of the radiocapitellar joint was largest in pronation. The contact area of the proximal radioulnar joint was largest in supination. The contact area of the ulnohumeral joint showed no significant change during forearm rotation. In pronation, because of the proximal migration of the radial head, the radiocapitellar joint was most congruent compared with other positions. The proximal radioulnar joint was most congruent in supination. The ulnohumeral joint congruency was not affected by forearm rotation. This study provides useful information for understanding 3-dimensional elbow motion and joint osseous stability related to forearm rotation. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Pronation-Supination Motion Is Altered in a Rat Model of Post-Traumatic Elbow Contracture.

PubMed

Dunham, Chelsey L; Castile, Ryan M; Chamberlain, Aaron M; Galatz, Leesa M; Lake, Spencer P

2017-07-01

The elbow joint is highly susceptible to joint contracture, and treating elbow contracture is a challenging clinical problem. Previously, we established an animal model to study elbow contracture that exhibited features similar to the human condition including persistent decreased range of motion (ROM) in flexion-extension and increased capsule thickness/adhesions. The objective of this study was to mechanically quantify pronation-supination in different injury models to determine if significant differences compared to control or contralateral persist long-term in our animal elbow contracture model. After surgically inducing soft tissue damage in the elbow, Injury I (anterior capsulotomy) and Injury II (anterior capsulotomy with lateral collateral ligament transection), limbs were immobilized for 6 weeks (immobilization (IM)). Animals were evaluated after the IM period or following an additional 6 weeks of free mobilization (FM). Total ROM for pronation-supination was significantly decreased compared to the uninjured contralateral limb for both IM and FM, although not different from control limbs. Specifically, for both IM and FM, total ROM for Injury I and Injury II was significantly decreased by ∼20% compared to contralateral. Correlations of measurements from flexion-extension and pronation-supination divulged that FM did not affect these motions in the same way, demonstrating that joint motions need to be studied/treated separately. Overall, injured limbs exhibited persistent motion loss in pronation-supination when comparing side-to-side differences, similar to human post-traumatic joint contracture. Future work will use this animal model to study how elbow periarticular soft tissues contribute to contracture.

Functional Consequence of Distal Brachioradialis Tendon Release: A Biomechanical Study

PubMed Central

Tirrell, Timothy F.; Franko, Orrin I.; Bhola, Siddharth; Hentzen, Eric R.; Abrams, Reid A.; Lieber, Richard L.

2013-01-01

Purpose Open reduction and internal fixation of distal radius fractures often necessitates release of the brachioradialis from the radial styloid. However, this common procedure has the potential to decrease elbow flexion strength. To determine the potential morbidity associated with brachioradialis release, we measured the change in elbow torque as a function of incremental release of the brachioradialis insertion footprint. Methods In 5 upper extremity cadaveric specimens, the brachioradialis tendon was systematically released from the radius, and the resultant effect on brachioradialis elbow flexion torque was measured. Release distance was defined as the distance between the release point and the tip of the radial styloid. Results Brachioradialis elbow flexion torque dropped to 95%, 90% and 86% of its original value at release distances of 27mm, 46mm, and 52mm, respectively. Importantly, brachioradialis torque remained above 80% of its original value at release distances up to 7 centimeters. Conclusions Our data demonstrate that release of the brachioradialis tendon from its insertion has minor effects on its ability to transmit force to the distal radius. Clinical Relevance These data may imply that release of the distal brachioradialis tendon during distal radius open reduction internal fixation can be performed without meaningful functional consequences to elbow flexion torque. Even at large release distances, overall elbow flexion torque loss after brachioradialis release would be expected to be less than 5% due to the much larger contributions of the biceps and brachialis. Use of the brachioradialis as a tendon transfer donor should not be limited by concerns of elbow flexion loss, and the tendon could be considered as an autograft donor. PMID:23528425

Three-dimensional analysis of elbow soft tissue footprints and anatomy.

PubMed

Capo, John T; Collins, Christopher; Beutel, Bryan G; Danna, Natalie R; Manigrasso, Michaele; Uko, Linda A; Chen, Linda Y

2014-11-01

Tendinous and ligamentous injuries commonly occur in the elbow. This study characterized the location, surface areas, and origin and insertional footprints of major elbow capsuloligamentous and tendinous structures in relation to bony landmarks with the use of a precision 3-dimensional modeling system. Nine unpaired cadaveric elbow specimens were dissected and mounted on a custom jig. Mapping of the medial collateral ligament (MCL), lateral ulnar collateral ligament (LUCL), triceps, biceps, brachialis, and capsular reflections was then performed with 3-dimensional digitizing technology. The location, surface areas, and footprints of the soft tissues were calculated. The MCL had a mean origin (humeral) footprint of 216 mm(2), insertional footprint of 154 mm(2), and surface area of 421 mm(2). The LUCL had a mean origin footprint of 136 mm(2), an insertional footprint of 142 mm(2), and a surface area of 532 mm(2). Of the tendons, the triceps maintained the largest insertional footprint, followed by the brachialis and the biceps (P < .001-.03). The MCL, LUCL, and biceps footprint locations were consistent, with little variability. The surface areas of the anterior (1251 mm(2)) and posterior (1147 mm(2)) capsular reflections were similar (P = .82), and the anterior capsule extended farther proximally. Restoring the normal anatomy of key elbow capsuloligamentous and tendinous structures is crucial for effective reconstruction after bony or soft tissue trauma. This study provides the upper extremity surgeon with information that may aid in restoring elbow biomechanics and preserving range of motion in these patients. Copyright © 2014 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

The first 100 elbow arthroscopies of one surgeon: analysis of complications.

PubMed

Marti, Darius; Spross, Christian; Jost, Bernhard

2013-04-01

Elbow arthroscopy is technically challenging and prone to complications especially due to the close relation of nerves and vessels. Complication rates up to 20% are reported, depending on indication and how complications are defined. This study analyzes the complications of the first 100 elbow arthroscopies done by 1 fellowship- and cadaver-trained surgeon. From September 2004 to April 2009, 100 consecutive elbow arthroscopies were performed, and thus consequently standardized, by 1 surgeon in 1 institution. The clinical data of all patients were retrospectively analyzed for indication-specific complications. Complications were divided into minor (transient) and major (persistent or infection). Included were 65 male and 35 female patients (mean age, 41 years; range, 12-70 years) with a minimum follow-up of 12 months (clinical or telephone). The following indications were documented (several per patient were possible): osteoarthritis in 29, stiffness in 27, loose bodies in 27, tennis elbow in 24, traumatic sequelae in 19, and others in 24. No major complications occurred, but 6 minor complications occurred in 5 patients (5%), comprising 2 hematoma, 2 transient nerve lesions, 1 wound-healing problem, and 1 complex regional pain syndrome. No revision surgery was necessary. Complications were not significantly associated with the indication for operation or the surgeon's learning curve. This study shows an acceptable complication rate of the first 100 elbow arthroscopies from a single surgeon. A profound clinical education, including cadaver training as well as standardization of patient position, portals, and surgery, help to achieve this. Copyright © 2013 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Mosby, Inc. All rights reserved.

Kinematic analysis of the thoracic limb of healthy dogs during descending stair and ramp exercises.

PubMed

Kopec, Nadia L; Williams, Jane M; Tabor, Gillian F

2018-01-01

OBJECTIVE To compare the kinematics of the thoracic limb of healthy dogs during descent of stairs and a ramp with those during a trot across a flat surface (control). ANIMALS 8 privately owned dogs. PROCEDURES For each dog, the left thoracic limb was instrumented with 5 anatomic markers to facilitate collection of 2-D kinematic data during each of 3 exercises (descending stairs, descending a ramp, and trotting over a flat surface). The stair exercise consisted of 4 steps with a 35° slope. For the ramp exercise, a solid plank was placed over the steps to create a ramp with a 35° slope. For the flat exercise, dogs were trotted across a flat surface for 2 m. Mean peak extension, peak flexion, and range of movement (ROM) of the shoulder, elbow, and carpal joints were compared among the 3 exercises. RESULTS Mean ROM for the shoulder and elbow joints during the stair exercise were significantly greater than during the flat exercise. Mean peak extension of the elbow joint during the flat exercise was significantly greater than that during both the stair and ramp exercises. Mean peak flexion of the elbow joint during the stair exercise was significantly greater than that during the flat exercise. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that descending stairs may be beneficial for increasing the ROM of the shoulder and elbow joints of dogs. Descending stair exercises may increase elbow joint flexion, whereas flat exercises may be better for targeting elbow joint extension.

Reliability and precision of stress sonography of the ulnar collateral ligament.

PubMed

Bica, David; Armen, Joseph; Kulas, Anthony S; Youngs, Kevin; Womack, Zachary

2015-03-01

Musculoskeletal sonography has emerged as an additional diagnostic tool that can be used to assess medial elbow pain and laxity in overhead throwers. It provides a dynamic, rapid, and noninvasive modality in the evaluation of ligamentous structural integrity. Many studies have demonstrated the utility of dynamic sonography for medial elbow and ulnar collateral ligament (UCL) integrity. However, evaluating the reliabilityand precision of these measurements is critical if sonography is ultimately used as a clinical diagnostic tool. The purpose of this study was to evaluate the reliability and precision of stress sonography applied to the medial elbow. We conducted a cross-sectional study during the 2011 baseball off-season. Eighteen National Collegiate Athletic Association Division I pitchers were enrolled, and 36 elbows were studied. Using sonography, the medial elbow was assessed, and measurements of the UCL length and ulnohumeral joint gapping were performed twice under two conditions (unloaded and loaded) and bilaterally. Intraclass correlation coefficients (0.72-0.94) and standard errors of measurements (0.3-0.9 mm) for UCL length and ulnohumeral joint gapping were good to excellent. Mean differences between unloaded and loaded conditions for the dominant arms were 1.3 mm (gapping; P < .001) and 1.4 mm (UCL length; P < .001). Medial elbow stress sonography is a reliable and precise method for detecting changes in ulnohumeral joint gapping and UCL lengthening. Ultimately, this method may provide clinicians valuable information regarding the medial elbow's response to valgus loading and may help guide treatment options. © 2015 by the American Institute of Ultrasound in Medicine.

A method to determine the orientation of the upper arm about its longitudinal axis during dynamic motions.

PubMed

Gordon, Brian J; Dapena, Jesús

2013-01-04

Inaccuracy in determining the orientation of the upper arm about its longitudinal axis (twist orientation) has been a pervasive problem in sport biomechanics research. The purpose of this study was to develop a method to improve the calculation of the upper arm twist orientation in dynamic sports activities. The twist orientation of the upper arm is defined by the orientation of its mediolateral axis. The basis for the new method is that at any angle in the flexion/extension range of an individual's elbow, it is possible to define a true mediolateral axis and also a surrogate mediolateral axis perpendicular to the plane containing the shoulder, elbow and wrist joints. The difference between the twist orientations indicated by these two versions of the mediolateral axis will vary from one elbow angle to another, but if the elbow joint deforms equally in different activities, for any given subject the difference should be constant at any given value of the elbow angle. Application of the new method required individuals to execute sedate elbow extension trials prior to the dynamic trials. Three-dimensional motion analysis of the sedate extension trials allowed quantification of the difference between the true and surrogate mediolateral axes for all angles in the entire flexion/extension range of an individual's elbow. This made it possible to calculate in any dynamic trial the twist orientation defined by the true mediolateral axis from the twist orientation defined by the surrogate mediolateral axis. The method was tested on a wooden model of the arm. Copyright © 2012 Elsevier Ltd. All rights reserved.

Proprioceptive illusions created by vibration of one arm are altered by vibrating the other arm.

PubMed

Hakuta, Naoyuki; Izumizaki, Masahiko; Kigawa, Kazuyoshi; Murai, Norimitsu; Atsumi, Takashi; Homma, Ikuo

2014-07-01

There is some evidence that signals coming from both arms are used to determine the perceived position and movement of one arm. We examined whether the sense of position and movement of one (reference) arm is altered by increases in muscle spindle signals in the other (indicator) arm in blindfolded participants (n = 26). To increase muscle spindle discharge, we applied 70-80 Hz muscle vibration to the elbow flexors of the indicator arm. In a first experiment, proprioceptive illusions in the vibrated reference arm in a forearm position-matching task were compared between conditions in which the indicator arm elbow flexors were vibrated or not vibrated. We found that the vibration illusion of arm extension induced by vibration of reference arm elbow flexors was reduced in the presence of vibration of the indicator elbow flexors. In a second experiment, participants were asked to describe their perception of the illusion of forearm extension movements of the reference arm evoked by vibration of reference arm elbow flexors in response to on/off and off/on transitions of vibration of non-reference arm elbow flexors. When vibration of non-reference arm elbow flexors was turned on, they reported a sensation of slowing down of the illusion of the reference arm. When it was turned off, they reported a sensation of speeding up. To conclude, the present study shows that both the sense of limb position and the sense of limb movement of one arm are dependent to some extent on spindle signals coming from the other arm.

Continuous passive motion and physical therapy (CPM) versus physical therapy (PT) versus delayed physical therapy (DPT) after surgical release for elbow contractures; a study protocol for a prospective randomized controlled trial.

PubMed

Viveen, Jetske; Doornberg, Job N; Kodde, Izaak F; Goossens, Pjotr; Koenraadt, Koen L M; The, Bertram; Eygendaal, Denise

2017-11-22

The elbow is prone to stiffness after trauma. To regain functional elbow motion several conservative- and surgical treatment options are available. Conservative treatment includes physical therapy, intra-articular injections with corticosteroids and a static progressive or dynamic splinting program. If conservative treatment fails, an operative release of the posttraumatic stiff elbow is often performed. The best Evidence-Based rehabilitation protocol for patients after an operative release is unknown to date and differs per surgeon, hospital and country. Options include early- or delayed motion supervised by a physical therapist, immediate continuous passive motion (CPM), (night) splinting and a static progressive or dynamic splinting program. The SET-Study (Stiff Elbow Trial) is a single-centre, prospective, randomized controlled trial. The primary objective of this study is to compare the active Range of Motion (ROM) (flexion arc and rotational arc) twelve months after surgery between three groups. The first group will receive in-hospital CPM in combination with early motion Physical Therapy (PT) supervised by a physical therapist, the second group will receive only in-hospital early motion PT supervised by a physical therapist and the third group will receive outpatient supervised PT from postoperative day seven till ten. Secondary outcome measures will be Patient Reported Outcome Measures (PROMs) including the Mayo Elbow Performance Score (MEPS), the Oxford Elbow Score (OES), the quick Disabilities of Arm, Shoulder and Hand (qDASH) score, Visual Analogue pain Scale in rest and activity (VAS), Pain Catastrophizing Scale (PCS), the Short Form (SF)-36, the Centre for Epidemiological Studies Depression Scale Revised (CESD-R) and the Work Rehabilitation Questionnaire (WORQ) for the upper limb. A successful completion of this trial will provide evidence on the best rehabilitation protocol in order to (re)gain optimal motion after surgical release of the stiff elbow. The trial is registered at the Dutch Trial Register: NTR6067 , 31-8-2016.

Ulnohumeral chondral and ligamentous overload: biomechanical correlation for posteromedial chondromalacia of the elbow in throwing athletes.

PubMed

Osbahr, Daryl C; Dines, Joshua S; Breazeale, Nathan M; Deng, Xiang-Hua; Altchek, David W

2010-12-01

Previous studies have documented increased posteromedial contact forces with the elbow at lower flexion angles associated with valgus extension overload; however, the authors believe that posteromedial elbow impingement in association with valgus laxity is a complex pathological process that may occur throughout the entire throwing motion in the form of ulnohumeral chondral and ligamentous overload. Valgus laxity with the elbow at 90° of flexion may lead to chondromalacia secondary to a subtle shift in the contact point between the tip of the olecranon and the distal humeral trochlea. Controlled laboratory study. Six fresh human cadaveric elbows were dissected and subjected to a static valgus load. Pressure-sensitive Fuji film measured the contact pressure, contact area, and shift in contact area across the posteromedial elbow before and after sectioning the anterior bundle of the ulnar collateral ligament. The contact pressure between the tip of the olecranon process and the medial crista of the posterior humeral trochlea significantly increased, from an average of 0.27 ± 0.06 kg/cm² to 0.40 ± 0.08 kg/cm². The contact area also significantly decreased, from an average of 30.34 ± 9.17 mm² to 24.59 ± 6.44 mm², and shifted medially on the medial humeral crista, which corresponds to the position of the posteromedial chondral lesions that was observed in throwing athletes in the authors' clinical practice. While simulating the early acceleration phase of the throwing motion with the elbow in 90° of flexion, the results illustrate that abnormal contact may occur as a result of valgus laxity through increased contact pressures across the posteromedial elbow between the medial tip of the olecranon and medial crista of the humeral trochlea. In addition, congruency of the ulnohumeral joint changed, as there was a statistically significant medial shift of the olecranon on the posterior humeral trochlea with the elbow at 90° of flexion after sectioning the anterior bundle of the ulnar collateral ligament. In the throwing athlete who continues the repetitive, throwing motion despite valgus laxity from ulnar collateral ligament insufficiency, the authors believe that these results provide a plausible mechanism for injury throughout the entire throwing motion secondary to ulnohumeral chondral and ligamentous overload. As throwing athletes may produce a tremendous amount of force and subsequent chondromalacia within the posteromedial aspect of the elbow, the findings of this study illustrate the importance of prompt clinical recognition of ulnar collateral ligament insufficiency.

Creep Deformation of Allvac 718Plus

DOE PAGES

Hayes, Robert W.; Unocic, Raymond R.; Nasrollahzadeh, Maryam

2014-11-11

The creep deformation behavior of Allvac 718Plus was studied over the temperature range 650° to 732°C at initial applied stress levels ranging from 517 to 655 MPa. Over the entire experimental temperature stress regime this alloy exhibits Class M type creep behavior with all creep curves exhibiting a decelerating strain rate with strain or time throughout primary creep. However, unlike pure metals or simple solid solution alloys this gamma prime strengthened superalloy does not exhibit steady state creep. Rather, primary creep is instantly followed by a long duration of accelerating strain rate with strain or time. These creep characteristics aremore » common amongst the gamma prime strengthened superalloys. Allvac 718Plus also exhibits a very high temperature dependence of creep rate. Detailed TEM examination of the deformation structures of selected creep samples reveals dislocation mechanisms similar to those found in high volume fraction gamma prime strengthened superalloys. Strong evidence of microtwinning is found in several of the deformation structures. The presence of microtwinning may account for the strong temperature dependence of creep rate observed in this alloy. In addition, due to the presence of Nb and thus, grain boundary delta phase, matrix dislocation activity which is not present in non Nb bearing superalloys occurs in this alloy. The creep characteristics and dislocation mechanisms are presented and discussed in detail.« less

Dislocation, crystallite size distribution and lattice strain of magnesium oxide nanoparticles

NASA Astrophysics Data System (ADS)

Sutapa, I. W.; Wahid Wahab, Abdul; Taba, P.; Nafie, N. L.

2018-03-01

The oxide of magnesium nanoparticles synthesized using sol-gel method and analysis of the structural properties was conducted. The functional groups of nanoparticles has been analysed by Fourier Transform Infrared Spectroscopy (FT-IR). Dislocations, average size of crystal, strain, stress, the energy density of crystal, crystallite size distribution and morphologies of the crystals were determined based on X-ray diffraction profile analysis. The morphological of the crystal was analysed based on the image resulted from SEM analysis. The crystallite size distribution was calculated with the contention that the particle size has a normal logarithmic form. The most orientations of crystal were determined based on the textural crystal from diffraction data of X-ray diffraction profile analysis. FT-IR results showed the stretching vibration mode of the Mg-O-Mg in the range of 400.11-525 cm-1 as a broad band. The average size crystal of nanoparticles resulted is 9.21 mm with dislocation value of crystal is 0.012 nm-2. The strains, stress, the energy density of crystal are 1.5 x 10-4 37.31 MPa; 0.72 MPa respectively. The highest texture coefficient value of the crystal is 0.98. This result is supported by morphological analysis using SEM which shows most of the regular cubic-shaped crystals. The synthesis method is suitable for simple and cost-effective synthesis model of MgO nanoparticles.

Dynamic strain aging and plastic instabilities

NASA Astrophysics Data System (ADS)

Mesarovic, Sinisa Dj.

1995-05-01

A constitutive model proposed by McCormick [(1988) Theory of flow localization due to dynamic strain ageing. Acta. Metall.36, 3061-3067] based on dislocation-solute interaction and describing dynamic strain aging behavior, is analyzed for the simple loading case of uniaxial tension. The model is rate dependent and includes a time-varying state variable, representing the local concentration of the impurity atoms at dislocations. Stability of the system and its post-instability behavior are considered. The methods used include analytical and numerical stability and bifurcation analysis with a numerical continuation technique. Yield point behavior and serrated yielding are found to result for well defined intervals of temperature and strain rate. Serrated yielding emerges as a branch of periodic solutions of the relaxation oscillation type, similar to frictional stick-slip. The distinction between the temporal and spatial (loss of homogeneity of strain) instability is emphasized. It is found that a critical machine stiffness exists above which a purely temporal instability cannot occur. The results are compared to the available experimental data.

Deformational Features and Microstructure Evolution of Copper Fabricated by a Single Pass of the Elliptical Cross-Section Spiral Equal-Channel Extrusion (ECSEE) Process

NASA Astrophysics Data System (ADS)

Wang, Chengpeng; Li, Fuguo; Liu, Juncheng

2018-04-01

The objectives of this work are to study the deformational feature, textures, microstructures, and dislocation configurations of ultrafine-grained copper processed by the process of elliptical cross-section spiral equal-channel extrusion (ECSEE). The deformation patterns of simple shear and pure shear in the ECSEE process were evaluated with the analytical method of geometric strain. The influence of the main technical parameters of ECSEE die on the effective strain distribution on the surface of ECSEE-fabricated samples was examined by the finite element simulation. The high friction factor could improve the effective strain accumulation of material deformation. Moreover, the pure copper sample fabricated by ECSEE ion shows a strong rotated cube shear texture. The refining mechanism of the dislocation deformation is dominant in copper processed by a single pass of ECSEE. The inhomogeneity of the micro-hardness distribution on the longitudinal section of the ECSEE-fabricated sample is consistent with the strain and microstructure distribution features.

SMALL ANGLE SCATTERING OF X-RAYS BY PLASTICALLY DEFORMED SINGLE CRYSTALS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robinson, W.H.; Smoluchowski, R.

1959-05-01

The small-angle scattering of x rays from single crystals of magnesium plastically deformed by simple shear was measured in the angular range of 4' to 5 deg . The crystals were subjected to both unidirectional and cyclic shear stresses applied along the STAl 1 2-bar 0! direction. Thin slices of the deformed single crystals were prepared using strainfree cutting and polishing techniques. The thin slices had orientations such that the slip direction was either parallel or perpendicular to the incident x-ray beam in order to observe any anisotropy in the scattering that might be due to dislocations. It was foundmore » that those samples which contained deformation twins within the irradiated volume produced rather large scattered intensity. This scattered intensity is interpreted as being due to double Bragg scattering. The scattered intensity from other specimens was attributed to surface scattering. No evidence for small angle scattering by dislocations was found. (auth)« less

Management of comminuted proximal ulna fracture-dislocations using a multiplanar locking intramedullary nail.

PubMed

Edwards, Scott G; Argintar, Evan; Lamb, Joshua

2011-06-01

Intramedullary nails have been used for the fixation of olecranon fractures in an attempt to reduce the soft tissue irritation and resulting need for hardware removal seen with plating and tension banding. Further benefits include preservation of vascular supply, and increase stability and improved compression over some alternative techniques. Most intramedullary nails have been limited to simple olecranon fractures or osteotomies. One novel multiplanar, locking intramedullary nail, however, is indicated to stabilize all fracture patterns of the proximal ulna, including the coronoid. This particular locking nail has screws that radiate in multiple planes and form a fixed-angle lattice throughout the bone. The nail also has fixed-angle screws dedicated to the 3 parts of the coronoid: process tip, medial facet, and medial wall. This allows the nail to secure multiple fragments regardless of the fracture pattern's extent of instability. The objective of this article is to illustrate the recommended steps in reducing and stabilizing a comminuted proximal ulna fracture-dislocation using this multiplanar locking intramedullary nail.

Multiscale modeling of dislocation-precipitate interactions in Fe: From molecular dynamics to discrete dislocations.

PubMed

Lehtinen, Arttu; Granberg, Fredric; Laurson, Lasse; Nordlund, Kai; Alava, Mikko J

2016-01-01

The stress-driven motion of dislocations in crystalline solids, and thus the ensuing plastic deformation process, is greatly influenced by the presence or absence of various pointlike defects such as precipitates or solute atoms. These defects act as obstacles for dislocation motion and hence affect the mechanical properties of the material. Here we combine molecular dynamics studies with three-dimensional discrete dislocation dynamics simulations in order to model the interaction between different kinds of precipitates and a 1/2〈111〉{110} edge dislocation in BCC iron. We have implemented immobile spherical precipitates into the ParaDis discrete dislocation dynamics code, with the dislocations interacting with the precipitates via a Gaussian potential, generating a normal force acting on the dislocation segments. The parameters used in the discrete dislocation dynamics simulations for the precipitate potential, the dislocation mobility, shear modulus, and dislocation core energy are obtained from molecular dynamics simulations. We compare the critical stresses needed to unpin the dislocation from the precipitate in molecular dynamics and discrete dislocation dynamics simulations in order to fit the two methods together and discuss the variety of the relevant pinning and depinning mechanisms.

[Homolateral Monteggia and Galeazzi fractures: a case report and review of the literature].

PubMed

Kanso, I; Tawil, H J; Lignac, F

2002-05-01

We report a very rare case of Monteggia and Galeazzi fractures of the same forearm in a 23-year-old female traffic accident victim. Fractures of the two forearm bones were reduced and fixed with a solid assembly. Dislocation of the radial head reduced spontaneously. Inferior radioulnar instability was treated by blocking the joint with a K wire for one month. At 24 months, outcome was satisfactory with 40 degrees pronation and 70 degrees supination. Elbow and wrist flexion-extension and muscle force were the same as on the healthy side. Surgery is indicated in this rare association in adults. As it is very important to restore exactly the anatomy with solid fixation of the ulna to achieve and maintain reduction of the radial head. Surgical exploration of the humeroradial joint is not required unless reduction cannot be achieved. The same is true for fixation of the radius after Galeazzi fracture. If an inferior radioulnar instability persists, we propose temporary stabilization with a K wire. Our experience with this case would argue against first intention resection of the distal portion of the ulna as proposed by Hughston. We prefer to postpone resection which would be performed only in case of bothersome instability. A Sauvé-Kapandji procedure would then be a possible solution.

Treating Intractable Post-Amputation Phantom Limb Pain with Ambulatory Continuous Peripheral Nerve Blocks

DTIC Science & Technology

2016-01-01

Upper ☐Lower Side of amputation: ☐Right ☐Left Level of original amputation (distal to…): ☐wrist/ ankle ☐elbow/knee...Right ☐Left Level of original amputation (distal to…): ☐wrist/ ankle ☐elbow/knee ☐shoulder/hip Initial Amputation Etiology...extremity: ☐Upper ☐Lower Side of amputation: ☐Right ☐Left Level of original amputation (distal to…): ☐wrist/ ankle ☐elbow/knee

Restoration of Elbow Flexion.

PubMed

Loeffler, Bryan J; Lewis, Daniel R

2016-08-01

Active elbow flexion is required to position the hand in space, and loss of this function is debilitating. Nerve transfers or nerve grafts to restore elbow flexion may be options when the target muscle is viable, but in delayed reconstruction when the biceps and brachialis are atrophied or damaged, muscle transfer options should be considered. Muscle transfer options are discussed with attention to the advantages and disadvantages of each transfer option. Copyright © 2016 Elsevier Inc. All rights reserved.

Extending prayer marks as a sign of worsening chronic disease.

PubMed

Cangiano, M; Chisti, Mohammod J; Pietroni, Mark A C; Smith, Jonathan H

2011-06-01

A 60-year-old Muslim man was admitted to the Dhaka Hospital of ICDDR,B with an exacerbation of his chronic obstructive pulmonary disease. Incidental hyperpigmented skin lesions were noticed overlying the dorsum of his ankles, knees, and elbows. Such asymptomatic areas of thickened, lichenified and hyperpigmented skin are called 'prayer marks' and are well-imprinted on the knees, ankles, and forehead. These are secondary to prolonged periods of pressure over bony prominences during prayer. The patient's wife stated that the appearance of the elbow marks had coincided with an increase in his breathlessness and subsequent use of his elbows to rise from daily prayers. Prayer marks extending to the elbows could be a sign of worsening chronic disease.

Total elbow arthroplasty in primary osteoarthritis of the elbow.

PubMed

Kozak, T K; Adams, R A; Morrey, B F

1998-10-01

Primary osteoarthritis of the elbow is an infrequent condition typically managed by some form of debridement. There is no comment in the literature regarding prosthetic replacement for this condition. We report 5 patients (mean age, 68), with a minimum assessment of 3 years (range, 37-125 years) after total elbow arthroplasty. Complications in 4 patients included subluxation, fracture of a humeral component with particulate synovitis, heterotopic ossification, recurrent osteophyte formation, and transient ulnar neuropathy. Although revision was required in 2 of the 5, currently all experience had satisfactory outcomes. While replacement has proven ultimately to be a successful option for this high-demand patient group because of the high complication rate, we do not recommend replacement unless alternate operative options are deemed unacceptable.

Determination of optimal tool parameters for hot mandrel bending of pipe elbows

NASA Astrophysics Data System (ADS)

Tabakajew, Dmitri; Homberg, Werner

2018-05-01

Seamless pipe elbows are important components in mechanical, plant and apparatus engineering. Typically, they are produced by the so-called `Hamburg process'. In this hot forming process, the initial pipes are subsequently pushed over an ox-horn-shaped bending mandrel. The geometric shape of the mandrel influences the diameter, bending radius and wall thickness distribution of the pipe elbow. This paper presents the numerical simulation model of the hot mandrel bending process created to ensure that the optimum mandrel geometry can be determined at an early stage. A fundamental analysis was conducted to determine the influence of significant parameters on the pipe elbow quality. The chosen methods and approach as well as the corresponding results are described in this paper.

Turbulent Heat-Transfer Coefficients in the Vicinity of Surface Protuberances

NASA Technical Reports Server (NTRS)

Wisniewski, Richard J.

1958-01-01

Local turbulent heating rates were obtained in the vicinity of surface protuberances mounted on the cylinder section of a cone cylinder model at a Mach number of 3.12. Data were obtained at Reynolds number per foot of 4.5 and 6 million for an unswept cylinder, a 45 deg swept cylinder, a 45 deg elbow, and several 90 deg elbows. The unswept cylinder and the 90 deg elbows increased the local turbulent heating rates in the vicinity of the surface protuberances. The data of the 45 deg swept cylinder and the 45 deg elbow resulted in heating rates lower than those observed without surface protuberances. In general, sweeping a surface protuberance resulted in heating rates comparable or lower than those measured without surface protuberances.

Dislocation evolution in 316 L stainless steel during multiaxial ratchetting deformation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dong Yawei; Kang Guozheng, E-mail: guozhengkang@yahoo.com.cn; Liu Yujie

2012-03-15

Dislocation patterns and their evolutions in 316 L stainless steel during the multiaxial ratchetting deformation were observed by transmission electron microscopy (TEM). The microscopic observations indicate that the dislocation evolution presented during the multiaxial ratchetting with four kinds of multiaxial loading paths is similar to that in the uniaxial case [G. Z. Kang et al., Mater Sci Eng A 527 (2010) 5952]. That is, dislocation networks and dislocation tangles are formed quickly by the multiple-slip and cross-slip of dislocation activated by applied multiaxial stress; and then polarized patterns such as dislocation walls and elongated incipient dislocation cells are formed atmore » the last stage of multiaxial ratchetting. The dislocation patterns evolve more quickly from the modes at low dislocation density to the ones at high density during the multiaxial ratchetting than that in the uniaxial case, and some traces of multiple-slip are observed in the multiaxial ones. The dislocation evolution during the multiaxial ratchetting deformation is summarized by comparing the observed dislocation patterns with those presented in the multiaxial strain-controlled and symmetrical stress-controlled cyclic tests. The multiaxial ratchetting of 316 L stainless steel can be microscopically and qualitatively explained by the observed evolution of dislocation patterns. - Highlights: Black-Right-Pointing-Pointer Dislocation patterns change from lines and nets to tangles, walls and cells. Black-Right-Pointing-Pointer Dislocation patterns evolve quicker in the multiaxial case. Black-Right-Pointing-Pointer Aligned dislocation arrays and some traces of multiple slips are observed. Black-Right-Pointing-Pointer Heterogeneous dislocation patterns result in the multiaxial ratchetting.« less

Worker Dislocation. Case Studies of Causes and Cures.

ERIC Educational Resources Information Center

Cook, Robert F., Ed.

Case studies were made of the following dislocated worker programs: Cummins Engine Company Dislocated Worker Project; GM-UAW Metropolitan Pontiac Retraining and Employment Program; Minnesota Iron Range Dislocated Worker Project; Missouri Dislocated Worker Program Job Search Assistance, Inc.; Hillsborough, North Carolina, Dislocated Worker Project;…

Column-by-column observation of dislocation motion in CdTe: Dynamic scanning transmission electron microscopy

NASA Astrophysics Data System (ADS)

Li, Chen; Zhang, Yu-Yang; Pennycook, Timothy J.; Wu, Yelong; Lupini, Andrew R.; Paudel, Naba; Pantelides, Sokrates T.; Yan, Yanfa; Pennycook, Stephen J.

2016-10-01

The dynamics of partial dislocations in CdTe have been observed at the atomic scale using aberration-corrected scanning transmission electron microscopy (STEM), allowing the mobility of different dislocations to be directly compared: Cd-core Shockley partial dislocations are more mobile than Te-core partials, and dislocation cores with unpaired columns have higher mobility than those without unpaired columns. The dynamic imaging also provides insight into the process by which the dislocations glide. Dislocations with dangling bonds on unpaired columns are found to be more mobile because the dangling bonds mediate the bond exchanges required for the dislocations to move. Furthermore, a screw dislocation has been resolved to dissociate into a Shockley partial-dislocation pair along two different directions, revealing a way for the screw dislocation to glide in the material. The results show that dynamic STEM imaging has the potential to uncover the details of dislocation motion not easily accessible by other means.

[Case-control study on measurement of coracoclavicular and acromioclavicular ligament injuries during internal fixation operation for the treatment of fresh acromioclavicular joint dislocation of Tossy type III].

PubMed

Guan, Ting-Jin; Sun, Peng; Zheng, Liang-Guo; Qi, Xiang-Yang

2014-01-01

To study measurement methods of acromioclavicular and coracoclavicular ligament injuries,its therapeutic effects and complications during internal fixation operation for the treatment of fresh acromioclavicular joint dislocations of Tossy type III. From July 2003 to May 2012,127 patients with acromioclavicular joint dislocations of Tossy type III were treated with wire fixation from coracoid process to clavicle or hook-plate fixation. The patients were divided into group A (63 cases) and group B (64 cases) according to whether acromioclavicular ligament and coracoclavicular ligament were repaired or not. In group A (ligaments repaired), there were 39 males and 24 females with an average age of (33.25 +/- 8.46) years old (ranged from 17 to 59 years). And in group B (no ligaments repaired), there were 41 males and 23 females with an average age of (34.10 +/- 7.19) years (ranged from 19 to 57 years). The operation times, intraoperative blood loss, postoperative infections, internal fixation failure, recurrence and other complications, together with therapeutic effects were compared between two groups. The outcome was analyzed according to Karlsson standard. In group A, 54 patients got an excellent result and 9 good according to Karlsson standard;the average operative time was (55.90 +/- 26.56) min; the average intraoperative bleeding amount was (99.80 +/- 50.30) ml; 1 patient had wire broken without re-dislocation at 16 weeks after operation, 3 patients got wound fat liquefaction and recovered after treatment, 1 patient had pain after shoulder joint motion and pain disappeared after implants were taken out. In group B, 52 patients got an excellent result and 12 good according to Karlsson standard; the average operative time was (49.50 +/- 23.14) min; the average intraoperative bleeding amount was (87.30 +/- 46.41) ml; 2 patients got wound fat liquefaction, and 2 patients had pain after shoulder joint motion. All the patients were followed up, and the duration ranged from 9 to 16 months. All internal steel-wire or hook plate were taken out during 4 to 9 months without acromioclavicular joint re dislocation. There were no significant difference in the average operative time, the average intraoperative blood less, complication recurrence rates of fixation failure, wound fat liquefaction, postoperative infection, acromioclavicular joint re-dislocation, and therapeutic effects between two groups. Both wire and clavicular hook plate fixation, performed for fresh acromioclavicular joint dislocation with Tossy type III, are simple, effective, less invasive method with less blood loss. In addition, the treatment without ligaments repaired could not increase incidence of complications.

Habitual dislocation of patella: A review

PubMed Central

Batra, Sumit; Arora, Sumit

2014-01-01

Habitual dislocation of patella is a condition where the patella dislocates whenever the knee is flexed and spontaneously relocates with extension of the knee. It is also termed as obligatory dislocation as the patella dislocates completely with each flexion and extension cycle of the knee and the patient has no control over the patella dislocating as he or she moves the knee1. It usually presents after the child starts to walk, and is often well tolerated in children, if it is not painful. However it may present in childhood with dysfunction and instability. Very little literature is available on habitual dislocation of patella as most of the studies have combined cases of recurrent dislocation with habitual dislocation. Many different surgical techniques have been described in the literature for the treatment of habitual dislocation of patella. No single procedure is fully effective in the surgical treatment of habitual dislocation of patella and a combination of procedures is recommended. PMID:25983506

Effect of distal ulnar collateral ligament tear pattern on contact forces and valgus stability in the posteromedial compartment of the elbow.

PubMed

Hassan, Sheref E; Parks, Brent G; Douoguih, Wiemi A; Osbahr, Daryl C

2015-02-01

It is not known whether the pattern of ulnar collateral ligament (UCL) tear affects elbow biomechanics. There will be a significant change in elbow biomechanics with 50% proximal but not 50% distal simulated rupture of the UCL. Controlled laboratory study. Pressure sensors in the posteromedial elbow joint of 25 male cadaveric elbows (average age, 54.9 years; range, 26-66 years) were used to measure contact area, pressure, and valgus torque at 90° and 30° of elbow flexion. Thirteen specimens were tested with the UCL intact, then with proximal-to-distal detachment of 50%, and then with proximal-to-distal detachment of 100% of the anterior band of the UCL from the ulnar attachment. This method was repeated in the remaining 12 specimens in a distal-to-proximal direction. With 50% proximal-to-distal detachment, contact area decreased significantly versus intact at 90° (91.3 ± 23.6 vs 112.2 ± 26.0 mm(2); P < .001) and 30° (69.3 ± 14.8 vs 83.1 ± 21.6 mm(2); P < .001) of elbow flexion; the center of pressure (COP) moved significantly proximally versus intact at 90° (3.8 ± 2.5 vs 5.4 ± 2.3 mm; P < .001) and 30° (5.9 ± 2.8 vs 7.4±1.9 mm; P < .001). With 50% distal-to-proximal UCL detachment versus intact, no significant change was observed in contact area, movement of the COP, or valgus laxity at either flexion position. With 100% proximal-to-distal and distal-to-proximal detachment, significant change in contact area, movement of the COP, and valgus laxity versus intact was found at 90° and 30° of elbow flexion (P < .05). No significant difference in contact pressure was observed in any test conditions. Significant change in contact area and proximal movement of the COP with 50% proximal UCL detachment and the lack of significant change with 50% distal UCL detachment suggest that the proximal half of the UCL ulnar footprint has a primary role in maintaining posteromedial elbow biomechanics. The findings suggest that surgical reconstruction should aim to reestablish at least the proximal 50% of the UCL ulnar footprint. © 2014 The Author(s).

Observations on the deformation-induced beta internal friction peak in bcc metals

NASA Technical Reports Server (NTRS)

Dicarlo, J. A.

1974-01-01

During a study of the effects of electron irradiation on the tungsten alpha mechanism, internal friction data were obtained. The data indicate that the mechanism underlying the beta peak does not possess the relaxation parameters generally associated with a simple dislocation process. The significance of the experimental results in the light of beta observations in other metals is discussed. It is suggested that the beta peaks in deformed bcc metals are the anelastic result of the thermally-activated relaxation of deformation-induced imperfections.

Atomic-scale investigation of point defects and hydrogen-solute atmospheres on the edge dislocation mobility in alpha iron

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhatia, M. A.; Solanki, K. N., E-mail: kiran.solanki@asu.edu; Groh, S.

2014-08-14

In this study, we present atomistic mechanisms of 1/2 [111](11{sup ¯}0) edge dislocation interactions with point defects (hydrogen and vacancies) and hydrogen solute atmospheres in body centered cubic (bcc) iron. In metals such as iron, increases in hydrogen concentration can increase dislocation mobility and/or cleavage-type decohesion. Here, we first investigate the dislocation mobility in the presence of various point defects, i.e., change in the frictional stress as the edge dislocation interacts with (a) vacancy, (b) substitutional hydrogen, (c) one substitutional and one interstitial hydrogen, (d) interstitial hydrogen, (e) vacancy and interstitial hydrogen, and (f) two interstitial hydrogen. Second, we examinemore » the role of a hydrogen-solute atmosphere on the rate of local dislocation velocity. The edge dislocation simulation with a vacancy in the compression side of the dislocation and an interstitial hydrogen atom at the tension side exhibit the strongest mechanical response, suggesting a higher potential barrier and hence, the higher frictional stress (i.e., ∼83% higher than the pure iron Peierls stress). In the case of a dislocation interacting with a vacancy on the compressive side, the vacancy binds with the edge dislocation, resulting in an increase in the friction stress of about 28% when compared with the Peierls stress of an edge dislocation in pure iron. Furthermore, as the applied strain increases, the vacancy migrates through a dislocation transportation mechanism by attaining a velocity of the same order as the dislocation velocity. For the case of the edge dislocation interacting with interstitial hydrogen on the tension side, the hydrogen atom jumps through one layer perpendicular to the glide plane during the pinning-unpinning process. Finally, our simulation of dislocation interactions with hydrogen show first an increase in the local dislocation velocity followed by a pinning of the dislocation core in the atmosphere, resulting in resistance to dislocation motion as the dislocation moves though the hydrogen-solute atmospheres. With this systematic, atomistic study of the edge dislocation with various point defects, we show significant increase in obstacle strengths in addition to an increase in the local dislocation velocity during interaction with solute atmospheres. The results have implications for constitutive development and modeling of the hydrogen effect on dislocation mobility and deformation in metals.« less

[Classification and Treatment of Sacroiliac Joint Dislocation].

PubMed

Tan, Zhen; Huang, Zhong; Li, Liang; Meng, Wei-Kun; Liu, Lei; Zhang, Hui; Wang, Guang-Lin; Huang, Fu-Guo

2017-09-01

To develop a renewed classification and treatment regimen for sacroiliac joint dislocation. According to the direction of dislocation of sacroiliac joint,combined iliac,sacral fractures,and fracture morphology,sacroiliac joint dislocation was classified into 4 types. Type Ⅰ (sacroiliac anterior dislocation): main fracture fragments of posterior iliac wing dislocated in front of sacroiliac joint. Type Ⅱ (sacroiliac posterior dislocation): main fracture fragments of posterior iliac wing dislocated in posterior of sacroiliac joint. Type Ⅲ (Crescent fracturedislocation of the sacroiliac joint): upward dislocation of posterior iliac wing with oblique fracture through posterior iliac wing. Type ⅢA: a large crescent fragment and dislocation comprises no more than onethird of sacroiliac joint,which is typically inferior. Type ⅢB: intermediatesize crescent fragment and dislocation comprises between one and twothirds of joint. Type ⅢC: a small crescent fragment where dislocation comprises most,but not the entire joint. Different treatment regimens were selected for different types of fractures. Treatment for type Ⅰ sacroiliac joint dislocation: anterior iliac fossa approach pry stripping reset; sacroiliac joint fixed with sacroiliac screw through percutaneous. Treatment for type Ⅱ sacroiliac joint dislocation: posterior sacroiliac joint posterior approach; sacroiliac joint fixed with sacroiliac screw under computer guidance. Treatment for type ⅢA and ⅢB sacroiliac joint dislocation: posterior sacroiliac joint approach; sacroiliac joint fixed with reconstruction plate. Treatment for type ⅢC sacroiliac joint dislocation: sacroiliac joint closed reduction; sacroiliac joint fixed with sacroiliac screw through percutaneous. Treatment for type Ⅳ sacroiliac joint dislocation: posterior approach; sacroiliac joint fixed with spinal pelvic fixation. Results of 24 to 72 months patient follow-up (mean 34.5 months): 100% survival,100% wound healing,and 100% fracture healing. Two cases were identified as type Ⅰ sacroiliac joint dislocation,including one with coexistence of nerve injury. Patients recovered completely 12 months after surgery. Eight cases were identified as type Ⅱ sacroiliac joint dislocation; none had obvious nerve injury during treatments. Twelve cases were identified as type Ⅲ sacroiliac joint dislocation,including one with coexistence of nerve injury. Patients recovered completely 12 months after surgery. Three cases were identified as type Ⅳ sacroiliac joint dislocation with coexistence of nerve injury. Two patients fully recovered 12 months after surgery. One had partial recovery of neurological function. The classification and treatment regimen for sacroiliac joint dislocation have achieved better therapeutic effect,which is worth promoting.

Comparison of shoulder internal rotation test with the elbow flexion test in the diagnosis of cubital tunnel syndrome.

PubMed

Ochi, Kensuke; Horiuchi, Yukio; Tanabe, Aya; Morita, Kozo; Takeda, Kentaro; Ninomiya, Ken

2011-05-01

To compare the shoulder internal rotation test-a new, provocative test-with the elbow flexion test in the diagnosis of cubital tunnel syndrome (CubTS). Twenty-five patients with CubTS were examined before and after surgery with 10 seconds each of the elbow flexion and shoulder internal rotation tests. Fifty-four asymptomatic individuals and 14 neuropathy patients with a diagnosis other than CubTS were also examined as control cases. For the shoulder internal rotation test, the patient's upper extremity was kept at 90° abduction, maximum internal rotation, and 10° flexion at the shoulder, with 90° elbow flexion and neutral position of the forearm and wrist, with finger extension. Test results were considered positive if any slight symptom attributable to CubTS occurred within 10 seconds. Extraneural pressure inside the cubital tunnel was intraoperatively measured with the positions of both the elbow flexion and shoulder internal rotation tests, in 15 of the CubTS cases. Statistical analyses were performed using Student's t-test with a confidence level of 95%. The preoperative sensitivity in CubTS cases was 80% in the 10-second shoulder internal rotation test and 36% in the 10-second elbow flexion test, and these differences were significant. None of the control cases had positive results in either test. All the CubTS cases improved with surgery; after surgery, neither test provoked symptoms in any surgical patient. The extraneural pressure increased in both provocative positions with no significant difference. Positive results for the 10-second shoulder internal rotation test were more sensitive than that for the elbow flexion test of the same duration and seemed specific to CubTS. Copyright © 2011 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Risk factors for decreased range of motion and poor outcomes in open periarticular elbow fractures.

PubMed

Dickens, Jonathan F; Wilson, Kevin W; Tintle, Scott M; Heckert, Reed; Gordon, Wade T; D'Alleyrand, Jean-Claude G; Potter, Benjamin K

2015-04-01

The purpose of this study was to identify risk factors present at the time of injury that predict poor functional outcomes and heterotopic ossification (HO) in open periarticular elbow fractures. We performed a retrospective review of 136 combat-related open elbow fractures from 2003 to 2010. Patient demographics, injury characteristics, treatment variables, and complications were recorded. Functional outcomes were analyzed to determine range of motion (ROM) and Mayo Elbow Performance Score (MEPS). Secondary outcome measures included the development of HO, return to duty, and revision operation. At a median 2.7 years from injury the median MEPS was 67.8 (range 30-100) with an average ulnohumeral arc motion of 89°. Bipolar fractures, with periarticular fractures on both sides of the elbow and at least one side containing intra-articular extension, were independently associated with decreased ulnohumeral motion (p=0.02) and decreased MEPS (p<0.004). Additional independent risk factors for decreased ROM included more severe osseous comminution (p=0.001), and increased time to definitive fixation (p=0.03) and HO (p=0.02). More severe soft tissue injury (Gustilo and Anderson fracture type, p=0.02), peripheral nerve injury (p=0.04), and HO (p=0.03) were independently associated with decreased MEPS. HO developed in 65% (89/136) of extremities and was associated with more severe Orthopaedic Trauma Association (OTA) fracture type (p=0.01) and escalating Gustilo and Anderson fracture classification (p=0.049). In the largest series of open elbow fractures, we identified risk factors that portend a poor clinical outcome and decreased ROM. Bipolar elbow fractures, which have not previously been associated with worse results, are particularly prone to decreased ROM and worse outcomes. Prognostic level IV. Published by Elsevier Ltd.

Prospective multifactorial analysis of preseason risk factors for shoulder and elbow injuries in high school baseball pitchers.

PubMed

Shitara, Hitoshi; Kobayashi, Tsutomu; Yamamoto, Atsushi; Shimoyama, Daisuke; Ichinose, Tsuyoshi; Tajika, Tsuyoshi; Osawa, Toshihisa; Iizuka, Haku; Takagishi, Kenji

2017-10-01

To prospectively identify preseason physical factors for shoulder and elbow injuries during the season in high school baseball pitchers. The study included 105 high school baseball pitchers [median age 16 (15-17) years]. The range of motion of the shoulder (90° abducted external and internal rotation) and elbow (extension/flexion), shoulder muscle strength (abduction and prone internal and external rotation), shoulder and elbow laxity, horizontal flexion, and scapular dyskinesis were assessed. After the season, the participants completed questionnaires regarding shoulder and/or elbow injuries, with injury defined as an inability to play for ≥1 week due to elbow/shoulder problems. The results of two groups (injured and noninjured) were compared using t tests and Chi-square analyses. Stepwise forward logistic regression models were developed to identify risk factors. Twenty-one injuries were observed. In univariate analysis, 90° abducted internal rotation and total arc of the dominant shoulder and the ratio of prone external rotation in the dominant to nondominant sides in the injured group were significantly less than those in the noninjured group (P = 0.02, 0.04, and 0.01, respectively). In logistic regression analysis, 90° abducted internal rotation in the dominant shoulder and prone external rotation ratio were significantly associated with injuries (P = 0.02 and 0.03, respectively). A low prone external rotation ratio and decreased 90° abducted internal rotation in the dominant shoulder in the preseason were significant risk factors for shoulder and elbow injuries in high school baseball pitchers. The results may contribute to reduce the incidence of these injuries. II.

Clinical rating systems in elbow research-a systematic review exploring trends and distributions of use.

PubMed

Evans, Jonathan P; Smith, Chris D; Fine, Nicola F; Porter, Ian; Gangannagaripalli, Jaheeda; Goodwin, Victoria A; Valderas, Jose M

2018-04-01

Clinical rating systems are used as outcome measures in clinical trials and attempt to gauge the patient's view of his or her own health. The choice of clinical rating system should be supported by its performance against established quality standards. A search strategy was developed to identify all studies that reported the use of clinical rating systems in the elbow literature. The strategy was run from inception in Medline Embase and CINHAL. Data extraction identified the date of publication, country of data collection, pathology assessed, and the outcome measure used. We identified 980 studies that reported clinical rating system use. Seventy-two separate rating systems were identified. Forty-one percent of studies used ≥2 separate measures. Overall, 54% of studies used the Mayo Elbow Performance Score (MEPS). For arthroplasty, 82% used MEPS, 17% used Disabilities of Arm, Shoulder and Hand (DASH), and 7% used QuickDASH. For trauma, 66.7% used MEPS, 32% used DASH, and 23% used the Morrey Score. For tendinopathy, 31% used DASH, 23% used Patient-Rated Tennis Elbow Evaluation (PRTEE), and 13% used MEPS. Over time, there was an increased proportional use of the MEPS, DASH, QuickDASH, PRTEE, and the Oxford Elbow Score. This study identified a wide choice and usage of clinical rating systems in the elbow literature. Numerous studies reported measures without a history of either a specific pathology or cross-cultural validation. Interpretability and comparison of outcomes is dependent on the unification of outcome measure choice. This was not demonstrated currently. Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Intrarater reliability of goniometry and hand-held dynamometry for shoulder and elbow examinations in female team handball athletes and asymptomatic volunteers.

PubMed

Fieseler, Georg; Molitor, Thomas; Irlenbusch, Lars; Delank, Karl-Stefan; Laudner, Kevin G; Hermassi, Souhail; Schwesig, Rene

2015-12-01

To evaluate the intrarater reliability for examining active range of motion (ROM) and isometric strength of the shoulder and elbow among asymptomatic female team handball athletes and a control group using a manual goniometer and hand-held dynamometry (HHD). 22 female team handball athletes (age: 21.0 ± 3.7 years) and 25 volunteers (13 female, 12 male, age: 21.9 ± 1.24 years) participated to determine bilateral ROM for shoulder rotation and elbow flexion/extension, as well as isometric shoulder rotation and elbow flexion/extension strength. Subjects were assessed on two separate test sessions with 7 days between sessions. Relative (intraclass correlation coefficients (ICC) and standard error of measurement (SEM) reliability were calculated. Reliability for ROM and strength were good to excellent for both shoulders and groups (athletes: ICC = 0.94-0.97, SEM 1.07°-4.76 N, controls: ICC = 0.96-1.00, SEM = 0.00 N-4.48 N). Elbow measurements for both groups also showed good-to-excellent reliability (athletes: ICC = 0.79-0.97, SEM = 0.98°-5.94 N, controls: ICC = 0.87-1.00, SEM = 0.00 N-5.43 N). It is important to be able to reliably reproduce active ROM and isometric strength evaluations. Using a standardized testing position, goniometry and HHD are reliable instruments in the assessment of shoulder and elbow joint performance testing. We showed good-to-excellent reproducible results for male and female control subjects and female handball athletes, although the single parameters in ROM and strength were different for each group and between the shoulders and elbows.

FUNCTIONAL OUTCOMES AFTER DISTAL BICEPS BRACHII REPAIR: A CASE SERIES

PubMed Central

Morris, Tim; Otto, Charissa; Zerella, Tanisha; Semmler, John G; Human, Taaibos; Phadnis, Joideep; Bain, Gregory I

2016-01-01

Objectives To investigate outcomes after surgical repair of distal biceps tendon rupture and the influence of arm dominance on isokinetic flexion and supination results. Background/Purpose While relatively uncommon, rupture of the distal biceps tendon can result in significant strength deficits, for which surgical repair is recommended. The purpose of this study was to assess patient reported functional outcomes and muscle performance following surgery. Methods A sample of 23 participants (22 males, 1 female), who had previously undergone surgical repair of the distal biceps tendon, were re-examined at a minimum of one year after surgery. Biodex isokinetic elbow flexion and supination testing was performed to assess strength (as measured by peak torque) and endurance (as measured by total work and work fatigue). The Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) and Mayo Elbow Performance Scale (MEPS) were used to assess participants' subjectively reported functional recovery. Results At a mean of 7.6 years after surgical repair, there were no differences between the repaired and uninvolved elbows in peak torque (p = 0.47) or total work (p = 0.60) for flexion or supination. There was also no difference in elbow flexion work fatigue (p = 0.22). However, there was significantly less work fatigue in supination, which was likely influenced by arm dominance, as most repairs were to the dominant arm, F(1,22)=5.67, p = 0.03. Conclusion The long-term strength of the repaired elbow was similar to the uninvolved elbow after surgery to the distal biceps tendon. Endurance of the repaired elbow was similar in flexion but greater in supination, probably influenced by arm dominance. Study design Retrospective case series Level of Evidence Level 4 PMID:27904798

A review of outcomes in 18 patients with floating elbow.

PubMed

Solomon, Harrison B; Zadnik, Mary; Eglseder, W Andrew

2003-09-01

To assess functional outcomes and predictors of success in floating elbow injuries. Retrospective clinical review. Level 1 trauma center. Eighteen patients with floating elbow injuries seen at the trauma center from 1995-2001. All injuries were managed surgically. Each forearm fracture was managed with open reduction and internal fixation. Humerus fractures were managed with either open reduction and internal fixation or intramedullary nail. Definitive fixation was performed in all cases within 48 hours of arrival at the trauma center. Eighteen patients were available for follow-up at a minimum of 1 year and consented to enroll in the study. Each patient was evaluated with a standardized elbow score based on a 100-point scale. These scores were correlated with injury features including age, severity of fracture (AO classification), open fractures, nerve injuries, vascular injuries, type of fixation on the humerus, and the presence of concomitant intra-articular elbow injuries. The average elbow score was 68/100. Outcomes were divided into two groups. Eleven patients had a score greater than 75 (group I), with a mean score of 83, and were considered to have a good or excellent result. Seven patients had a score less than 75 (group II), with a mean score of 45, and were considered to have a satisfactory or poor result. The distribution of outcomes revealed two statistically distinct clusters. Additionally, there was a significantly higher incidence of nerve injuries in group 2 compared with group 1. Functional outcomes in floating elbow injuries tend to cluster into two groups-patients with good or excellent results and patients with poor results. Patients with associated nerve injuries have lower functional outcomes at a minimum of 1-year follow-up.

FUNCTIONAL OUTCOMES AFTER DISTAL BICEPS BRACHII REPAIR: A CASE SERIES.

PubMed

Redmond, Christine L; Morris, Tim; Otto, Charissa; Zerella, Tanisha; Semmler, John G; Human, Taaibos; Phadnis, Joideep; Bain, Gregory I

2016-12-01

To investigate outcomes after surgical repair of distal biceps tendon rupture and the influence of arm dominance on isokinetic flexion and supination results. While relatively uncommon, rupture of the distal biceps tendon can result in significant strength deficits, for which surgical repair is recommended. The purpose of this study was to assess patient reported functional outcomes and muscle performance following surgery. A sample of 23 participants (22 males, 1 female), who had previously undergone surgical repair of the distal biceps tendon, were re-examined at a minimum of one year after surgery. Biodex isokinetic elbow flexion and supination testing was performed to assess strength (as measured by peak torque) and endurance (as measured by total work and work fatigue). The Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) and Mayo Elbow Performance Scale (MEPS) were used to assess participants' subjectively reported functional recovery. At a mean of 7.6 years after surgical repair, there were no differences between the repaired and uninvolved elbows in peak torque ( p  = 0.47) or total work ( p  = 0.60) for flexion or supination. There was also no difference in elbow flexion work fatigue ( p  = 0.22). However, there was significantly less work fatigue in supination, which was likely influenced by arm dominance, as most repairs were to the dominant arm, F (1,22)=5.67, p  = 0.03. The long-term strength of the repaired elbow was similar to the uninvolved elbow after surgery to the distal biceps tendon. Endurance of the repaired elbow was similar in flexion but greater in supination, probably influenced by arm dominance. Retrospective case series. Level 4.

The Thrower's Elbow: Arthroscopic Treatment of Valgus Extension Overload Syndrome

PubMed Central

Altchek, David W.

2006-01-01

Injury to the medial collateral ligament of the elbow (MCL) can be a career-threatening injury for an overhead athlete without appropriate diagnosis and treatment. It has been considered separately from other athletic injuries due to the unique constellation of pathology that results from repetitive overhead throwing. The past decade has witnessed tremendous gains in understanding of the complex interplay between the dynamic and static stabilizers of the athlete's elbow. Likewise, the necessity to treat these problems in a minimally invasive manner has driven the development of sophisticated techniques and instrumentation for elbow arthroscopy. MCL injuries, ulnar neuritis, valgus extension overload with osteophyte formation and posteromedial impingement, flexor pronator strain, medial epicondyle pathology, and osteochondritis dissecans (OCD) of the capitellum have all been described as sequelae of the overhead throwing motion. In addition, loose body formation, bony spur formation, and capsular contracture can all be present in conjunction with these problems or as isolated entities. Not all pathology in the thrower's elbow is amenable to arthroscopic treatment; however, the clinician must be familiar with all of these problems in order to form a comprehensive differential diagnosis for an athlete presenting with elbow pain, and he or she must be comfortable with the variety of open and arthroscopic treatments available to best serve the patient. An understanding of the anatomy and biomechanics of the thrower's elbow is critical to the care of this population. The preoperative evaluation should focus on a thorough history and physical examination, as wellas on specific diagnostic imaging modalities. Arthroscopic setup, including anesthesia, patient positioning, and portal choices will be discussed. Operative techniques in the anterior and posterior compartments will bereviewed, as well as postoperative rehabilitationandsurgical results. Lastly, complications will be reviewed. PMID:18751853

Elbow joint position sense after neuromuscular training with handheld vibration.

PubMed

Tripp, Brady L; Faust, Donald; Jacobs, Patrick

2009-01-01

Clinicians use neuromuscular control exercises to enhance joint position sense (JPS); however, because standardizing such exercises is difficult, validations of their use are limited. To evaluate the acute effects of a neuromuscular training exercise with a handheld vibrating dumbbell on elbow JPS acuity. Crossover study. University athletic training research laboratory. Thirty-one healthy, college-aged volunteers (16 men, 15 women, age = 23 + or - 3 years, height = 173 + or - 8 cm, mass = 76 + or - 14 kg). We measured and trained elbow JPS using an electromagnetic tracking device that provided auditory and visual biofeedback. For JPS testing, participants held a dumbbell and actively identified the target elbow flexion angle (90 degrees ) using the software-generated biofeedback, followed by 3 repositioning trials without feedback. Each neuromuscular training protocol included 3 exercises during which participants held a 2.55-kg dumbbell vibrating at 15, 5, or 0 Hz and used software-generated biofeedback to locate and maintain the target elbow flexion angle for 15 seconds. We calculated absolute (accuracy) and variable (variability) errors using the differences between target and reproduced angles. Training protocols using 15-Hz vibration enhanced accuracy and decreased variability of elbow JPS (P < or = .005), whereas 5-Hz vibration did not affect accuracy (F(1,61) = 2.625, P = .100) but did decrease variability (F(1,61) = 7.250, P = .009). The control condition and 0-Hz training protocol had no effect on accuracy or variability (P > or = .200). Our results suggest these neuromuscular control exercises, which included low-magnitude, low-frequency handheld vibration, may enhance elbow JPS. Future researchers should examine vibration of various durations and frequencies, should include injured participants and functional multijoint and multiplanar measures, and should examine long-term effects of training protocols on JPS and injury.

Generalized continuum modeling of scale-dependent crystalline plasticity

NASA Astrophysics Data System (ADS)

Mayeur, Jason R.

The use of metallic material systems (e.g. pure metals, alloys, metal matrix composites) in a wide range of engineering applications from medical devices to electronic components to automobiles continues to motivate the development of improved constitutive models to meet increased performance demands while minimizing cost. Emerging technologies often incorporate materials in which the dominant microstructural features have characteristic dimensions reaching into the submicron and nanometer regime. Metals comprised of such fine microstructures often exhibit unique and size-dependent mechanical response, and classical approaches to constitutive model development at engineering (continuum) scales, being local in nature, are inadequate for describing such behavior. Therefore, traditional modeling frameworks must be augmented and/or reformulated to account for such phenomena. Crystal plasticity constitutive models have proven quite capable of capturing first-order microstructural effects such as grain orientation (elastic/plastic anisotropy), grain morphology, phase distribution, etc. on the deformation behavior of both single and polycrystals, yet suffer from the same limitations as other local continuum theories with regard to capturing scale-dependent mechanical response. This research is focused on the development, numerical implementation, and application of a generalized (nonlocal) theory of single crystal plasticity capable of describing the scale-dependent mechanical response of both single and polycrystalline metals that arises as a result of heterogeneous deformation. This research developed a dislocation-based theory of micropolar single crystal plasticity. The majority of nonlocal crystal plasticity theories are predicated on the connection between gradients of slip and geometrically necessary dislocations. Due to the diversity of existing nonlocal crystal plasticity theories, a review, summary, and comparison of representative model classes is presented in Chapter 2 from a unified dislocation-based perspective. The discussion of the continuum crystal plasticity theories is prefaced by a brief review of discrete dislocation plasticity, which facilitates the comparison of certain model aspects and also serves as a reference for latter segments of the research which make connection to this constitutive description. Chapter 2 has utility not only as a literature review, but also as a synthesis and analysis of competing and alternative nonlocal crystal plasticity modeling strategies from a common viewpoint. The micropolar theory of single crystal plasticity is presented in Chapter 3. Two different types of flow criteria are considered - the so-called single and multicriterion theories, and several variations of the dislocation-based strength models appropriate for each theory are presented and discussed. The numerical implementation of the two-dimensional version of the constitutive theory is given in Chapter 4. A user element subroutine for the implicit commercial finite element code Abaqus/Standard is developed and validated through the solution of initial-boundary value problems with closed-form solutions. Convergent behavior of the subroutine is also demonstrated for an initial-boundary value problem exhibiting strain localization. In Chapter 5, the models are employed to solve several standard initial-boundary value problems for heterogeneously deforming single crystals including simple shearing of a semi-infinite constrained thin film, pure bending of thin films, and simple shearing of a metal matrix composite with elastic inclusions. The simulation results are compared to those obtained from the solution of equivalent boundary value problems using discrete dislocation dynamics and alternative generalized crystal plasticity theories. Comparison and calibration with respect to the former provides guidance in the specification of non-traditional material parameters that arise in the model formulation and demonstrates its effectiveness at capturing the heterogeneous deformation fields and size-dependent mechanical behavior predicted by a finer scale constitutive description. Finally, in Chapter 6, the models are applied to simulate the deformation behavior of small polycrystalline ensembles. Several grain boundary constitutive descriptions are explored and the response characteristics are analyzed with respect to experimental observations as well as results obtained from discrete dislocation dynamics and alternative nonlocal crystal plasticity theories. Particular attention is focused on how the various grain boundary descriptions serve to either locally concentrate or diffuse deformation heterogeneity as a function of grain size.

Effects of equal-volume resistance training with different training frequencies in muscle size and strength in trained men

PubMed Central

Fisher, James; Steele, James; Campos, Mario H.; Silva, Marcelo H.; Paoli, Antonio; Giessing, Jurgen; Bottaro, Martim

2018-01-01

Background The objective of the present study was to compare the effects of equal-volume resistance training (RT) performed with different training frequencies on muscle size and strength in trained young men. Methods Sixteen men with at least one year of RT experience were divided into two groups, G1 and G2, that trained each muscle group once and twice a week, respectively, for 10 weeks. Elbow flexor muscle thickness (MT) was measured using a B-Mode ultrasound and concentric peak torque of elbow extensors and flexors were assessed by an isokinetic dynamometer. Results ANOVA did not reveal group by time interactions for any variable, indicating no difference between groups for the changes in MT or PT of elbow flexors and extensors. Notwithstanding, MT of elbow flexors increased significantly (3.1%, P < 0.05) only in G1. PT of elbow flexors and extensors did not increase significantly for any group. Discussion The present study suggest that there were no differences in the results promoted by equal-volume resistance training performed once or twice a week on upper body muscle strength in trained men. Only the group performing one session per week significantly increased the MT of their elbow flexors. However, with either once or twice a week training, adaptations appear largely minimal in previously trained males.

Effects of equal-volume resistance training with different training frequencies in muscle size and strength in trained men.

PubMed

Gentil, Paulo; Fisher, James; Steele, James; Campos, Mario H; Silva, Marcelo H; Paoli, Antonio; Giessing, Jurgen; Bottaro, Martim

2018-01-01

The objective of the present study was to compare the effects of equal-volume resistance training (RT) performed with different training frequencies on muscle size and strength in trained young men. Sixteen men with at least one year of RT experience were divided into two groups, G1 and G2, that trained each muscle group once and twice a week, respectively, for 10 weeks. Elbow flexor muscle thickness (MT) was measured using a B-Mode ultrasound and concentric peak torque of elbow extensors and flexors were assessed by an isokinetic dynamometer. ANOVA did not reveal group by time interactions for any variable, indicating no difference between groups for the changes in MT or PT of elbow flexors and extensors. Notwithstanding, MT of elbow flexors increased significantly (3.1%, P  < 0.05) only in G1. PT of elbow flexors and extensors did not increase significantly for any group. The present study suggest that there were no differences in the results promoted by equal-volume resistance training performed once or twice a week on upper body muscle strength in trained men. Only the group performing one session per week significantly increased the MT of their elbow flexors. However, with either once or twice a week training, adaptations appear largely minimal in previously trained males.

MR imaging of patients with lateral epicondylitis of the elbow: is the common extensor tendon an isolated lesion?

PubMed

Qi, Liang; Zhu, Zheng-Feng; Li, Feng; Wang, Ren-Fa

2013-01-01

To investigate whether an injury of the common extensor tendon (CET) is associated with other abnormalities in the elbow joint and find the potential relationships between these imaging features by using a high-resolution magnetic resonance imaging (MRI). Twenty-three patients were examined with 3.0 T MR. Two reviewers were recruited for MR images evaluation. Image features were recorded in terms of (1) the injury degree of CET; (2) associated injuries in the elbow joint. Spearman's rank correlation analysis was performed to analyze the relationships between the injury degree of CET and associated abnormalities of the elbow joint, correlations were considered significant at p<0.05. Total 24 elbows in 23 patients were included. Various degrees of injuries were found in total 24 CETs (10 mild, 7 moderate and 7 severe). Associated abnormalities were detected in accompaniments of the elbow joints including ligaments, tendons, saccussynovialis and muscles. A significantly positive correlation (r = 0.877,p<0.01) was found in injuries of CET and lateral ulnar collateral ligament (LUCL). Injury of the CET is not an isolated lesion for lateral picondylitis, which is mostly accompanied with other abnormalities, of which the LUCL injury is the most commonly seen in lateral epicondylitis, and there is a positive correlation between the injury degree in CET and LUCL.

Subject-specific computer simulation model for determining elbow loading in one-handed tennis backhand groundstrokes.

PubMed

King, Mark A; Glynn, Jonathan A; Mitchell, Sean R

2011-11-01

A subject-specific angle-driven computer model of a tennis player, combined with a forward dynamics, equipment-specific computer model of tennis ball-racket impacts, was developed to determine the effect of ball-racket impacts on loading at the elbow for one-handed backhand groundstrokes. Matching subject-specific computer simulations of a typical topspin/slice one-handed backhand groundstroke performed by an elite tennis player were done with root mean square differences between performance and matching simulations of < 0.5 degrees over a 50 ms period starting from ball impact. Simulation results suggest that for similar ball-racket impact conditions, the difference in elbow loading for a topspin and slice one-handed backhand groundstroke is relatively small. In this study, the relatively small differences in elbow loading may be due to comparable angle-time histories at the wrist and elbow joints with the major kinematic differences occurring at the shoulder. Using a subject-specific angle-driven computer model combined with a forward dynamics, equipment-specific computer model of tennis ball-racket impacts allows peak internal loading, net impulse, and shock due to ball-racket impact to be calculated which would not otherwise be possible without impractical invasive techniques. This study provides a basis for further investigation of the factors that may increase elbow loading during tennis strokes.

Experimental and numerical investigation of centrifugal pumps with asymmetric inflow conditions

NASA Astrophysics Data System (ADS)

Mittag, Sten; Gabi, Martin

2015-11-01

Most of the times pumps operate off best point states. Reasons are changes of operating conditions, modifications, pollution and wearout or erosion. As consequences non-rotational symmetric flows, transient operational conditions, increased risk of cavitation, decrease of efficiency and unpredictable wearout can appear. Especially construction components of centrifugal pumps, in particular intake elbows, contribute to this matter. Intake elbows causes additional losses and secondary flows, hence non-rotational velocity distributions as intake profile to the centrifugal pump. As a result the impeller vanes experience permanent changes of the intake flow angle and with it transient flow conditions in the blade channels. This paper presents the first results of a project, experimentally and numerically investigating the consequences of non-rotational inflow to leading edge flow conditions of a centrifugal pump. Therefore two pumpintake- elbow systems are compared, by only altering the intake elbow geometry: a common single bended 90° elbow and a numerically optimized elbow (improved regarding rotational symmetric inflow conditions and friction coefficient). The experiments are carried out, using time resolved stereoscopic PIV on a full acrylic pump with refractions index matched (RIM) working fluid. This allows transient investigations of the flow field simultaneously for all blade leading edges. Additional CFD results are validated and used to further support the investigation i.e. for comparing an analog pump system with ideal inflow conditions.

Directionally compliant legs influence the intrinsic pitch behaviour of a trotting quadruped

PubMed Central

Lee, David V; Meek, Sanford G

2005-01-01

Limb design is well conserved among quadrupeds, notably, the knees point forward (i.e. cranial inclination of femora) and the elbows point back (i.e. caudal inclination of humeri). This study was undertaken to examine the effects of joint orientation on individual leg forces and centre of mass dynamics. Steady-speed trotting was simulated in two quadrupedal models. Model I had the knee and elbow orientation of a quadruped and model II had a reversed leg configuration in which knees point back and elbows point forward. The model's legs showed directional compliance determined by the orientation of the knee/elbow. In both models, forward pointing knees/elbows produced a propulsive force bias, while rearward pointing knees/elbows produced a braking force bias. Hence, model I showed the same pattern of hind-leg propulsion and fore-leg braking observed in trotting animals. Simulations revealed minimal pitch oscillations during steady-speed trotting of model I, but substantially greater and more irregular pitch oscillations of model II. The reduced pitch oscillation of model I was a result of fore-leg and hind-leg forces that reduced pitching moments during early and late stance, respectively. This passive mechanism for reducing pitch oscillations was an emergent property of directionally compliant legs with the fore–hind configuration of model I. Such intrinsic stability resulting from mechanical design can simplify control tasks and lead to more robust running machines. PMID:15817430

Partial rotator cuff repair and biceps tenotomy for the treatment of patients with massive cuff tears and retained overhead elevation: midterm outcomes with a minimum 5 years of follow-up.

PubMed

Cuff, Derek J; Pupello, Derek R; Santoni, Brandon G

2016-11-01

A subset of patients with massive irreparable rotator cuff tears present with retained overhead elevation and pain as their primary complaint. Our aim was to evaluate the outcomes of partial arthroscopic rotator cuff repair with biceps tenotomy and to report the failure rate of this procedure for patients with >5 years of follow-up. Thirty-four patients underwent partial rotator cuff repair and biceps tenotomy for treatment of a massive rotator cuff tear. Patients had preoperative active forward elevation >120° and no radiographic evidence of glenohumeral arthritis. Patients were followed up clinically and radiographically, and 28 patients had a minimum of 5 years of follow-up. Failure was defined as an American Shoulder and Elbow Surgeons score of <70, loss of active elevation >90°, or revision to reverse shoulder arthroplasty during the study period. Patients demonstrated improvements in average preoperative to postoperative American Shoulder and Elbow Surgeons scores (46.6 to 79.3 [P < .001]) and Simple Shoulder Test scores (5.7 to 9.1 [P < .001]) along with decrease in visual analog scale for pain scores (6.9 to 1.9 [P < .001]). No significant change in forward elevation (168° to 154° [P = .07]), external rotation (38° to 39° [P = 1.0]), or internal rotation (84% to 80% [P = 1.0]) was identified; 36% of patients had progression of the Hamada stage. The failure rate was 29%; 75% of patients were satisfied with their index procedure. Partial rotator cuff repair and biceps tenotomy for patients with massive irreparable rotator cuff tears with retained overhead elevation and pain as the primary complaint produced reasonable outcomes at midterm follow-up of at least 5 years. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Tennis elbow surgery - discharge

MedlinePlus

Lateral epicondylitis surgery - discharge; Lateral tendinosis surgery - discharge; Lateral tennis elbow surgery - discharge ... Soon after surgery, severe pain will decrease, but you may have mild soreness for 3 to 6 months.

Arthroscopic management of the painful total elbow arthroplasty

PubMed Central

Bain, Gregory I

2015-01-01

Background Failure of total elbow arthroplasty is more common than after other major joint arthroplasties and is often a result of aseptic loosening, peri-prosthetic infection, fracture and instability. Infection can be a devastating complication, yet there are no established guidelines for the pre-operative diagnosis of total elbow peri-prosthetic infection. This is because pre-operative clinical, radiographic and biochemical tests are often unreliable. Methods Using three case examples, a standardized protocol for the clinical and arthroscopic assessment of the painful total elbow arthroplasty is described. This is used to provide a mechanical and microbiological diagnosis of the patient’s pain. Results There have been no complications resulting from the use of this technique in the three patients described, nor in any other patient to date. Conclusions The staged protocol described in the present study, utilizing arthroscopic assessment, has refined the approach to the painful total elbow arthroplasty because it directly influences the definitive surgical management of the patient. It is recommended that other surgeons follow the principles outlined in the present study when faced with this challenging problem. PMID:27583000

Electrodiagnosis of ulnar neuropathy at the elbow (Une): a Bayesian approach.

PubMed

Logigian, Eric L; Villanueva, Raissa; Twydell, Paul T; Myers, Bennett; Downs, Marlene; Preston, David C; Kothari, Milind J; Herrmann, David N

2014-03-01

In ulnar neuropathy at the elbow (UNE), we determined how electrodiagnostic cutoffs [across-elbow ulnar motor conduction velocity slowing (AECV-slowing), drop in across-elbow vs. forearm CV (AECV-drop)] depend on pretest probability (PreTP). Fifty clinically defined UNE patients and 50 controls underwent ulnar conduction testing recording abductor digiti minimi (ADM) and first dorsal interosseous (FDI), stimulating wrist, below-elbow, and 6-, 8-, and 10-cm more proximally. For various PreTPs of UNE, the cutoffs required to confirm UNE (defined as posttest probability = 95%) were determined with receiver operator characteristic (ROC) curves and Bayes Theorem. On ROC and Bayesian analyses, the ADM 10-cm montage was optimal. For PreTP = 0.25, the confirmatory cutoffs were >23 m/s (AECV-drop), and <38 m/s (AECV-slowing); for PreTP = 0.75, they were much less conservative: >14 m/s, and <47 m/s, respectively. (1) In UNE, electrodiagnostic cutoffs are critically dependent on PreTP; rigid cutoffs are problematic. (2) AE distances should be standardized and at least 10 cm. Copyright © 2013 Wiley Periodicals, Inc.

3D discrete dislocation dynamics study of creep behavior in Ni-base single crystal superalloys by a combined dislocation climb and vacancy diffusion model

NASA Astrophysics Data System (ADS)

Gao, Siwen; Fivel, Marc; Ma, Anxin; Hartmaier, Alexander

2017-05-01

A three-dimensional (3D) discrete dislocation dynamics (DDD) creep model is developed to investigate creep behavior under uniaxial tensile stress along the crystallographic [001] direction in Ni-base single crystal superalloys, which takes explicitly account of dislocation glide, climb and vacancy diffusion, but neglects phase transformation like rafting of γ‧ precipitates. The vacancy diffusion model takes internal stresses by dislocations and mismatch strains into account and it is coupled to the dislocation dynamics model in a numerically efficient way. This model is helpful for understanding the fundamental creep mechanisms in superalloys and clarifying the effects of dislocation glide and climb on creep deformation. In cases where the precipitate cutting rarely occurs, e.g. due to the high anti-phase boundary energy and the lack of superdislocations, the dislocation glide in the γ matrix and the dislocation climb along the γ/γ‧ interface dominate plastic deformation. The simulation results show that a high temperature or a high stress both promote dislocation motion and multiplication, so as to cause a large creep strain. Dislocation climb accelerated by high temperature only produces a small plastic strain, but relaxes the hardening caused by the filling γ channels and lets dislocations further glide and multiply. The strongest variation of vacancy concentration occurs in the horizontal channels, where more mixed dislocations exit and tend to climb. The increasing internal stresses due to the increasing dislocation density are easily overcome by dislocations under a high external stress that leads to a long-term dislocation glide accompanied by multiplication.

Interfacial dislocations in (111) oriented (Ba 0.7Sr 0.3)TiO 3 films on SrTiO 3 single crystal

DOE PAGES

Shen, Xuan; Yamada, Tomoaki; Lin, Ruoqian; ...

2015-10-08

In this study, we have investigated the interfacial structure of epitaxial (Ba,Sr)TiO 3 films grown on (111)-oriented SrTiO 3 single-crystal substrates using transmission electron microscopy (TEM) techniques. Compared with the (100) epitaxial perovskite films, we observe dominant dislocation half-loop with Burgers vectors of a<110> comprised of a misfit dislocation along <112>, and threading dislocations along <110> or <100>. The misfit dislocation with Burgers vector of a <110> can dissociate into two ½ a <110> partial dislocations and one stacking fault. We found the dislocation reactions occur not only between misfit dislocations, but also between threading dislocations. Via three-dimensional electron tomography,more » we retrieved the configurations of the threading dislocation reactions. The reactions between threading dislocations lead to a more efficient strain relaxation than do the misfit dislocations alone in the near-interface region of the (111)-oriented (Ba 0.7Sr 0.3)TiO 3 films.« less

Dislocation mechanisms in stressed crystals with surface effects

NASA Astrophysics Data System (ADS)

Wu, Chi-Chin; Crone, Joshua; Munday, Lynn; Discrete Dislocation Dynamics Team

2014-03-01

Understanding dislocation properties in stressed crystals is the key for important processes in materials science, including the strengthening of metals and the stress relaxation during the growth of hetero-epitaxial structures. Despite existing experimental approaches and theories, many dislocation mechanisms with surface effects still remain elusive in experiments. Even though discrete dislocation dynamics (DDD) simulations are commonly employed to study dislocations, few demonstrate sufficient computational capabilities for massive dislocations with the combined effects of surfaces and stresses. Utilizing the Army's newly developed FED3 code, a DDD computation code coupled with finite elements, this work presents several dislocation mechanisms near different types of surfaces in finite domains. Our simulation models include dislocations in a bended metallic cantilever beam, near voids in stressed metals, as well as threading and misfit dislocations in as-grown semiconductor epitaxial layers and their quantitative inter-correlations to stress relaxation and surface instability. Our studies provide not only detailed physics of individual dislocation mechanisms, but also important collective dislocation properties such as dislocation densities and strain-stress profiles and their interactions with surfaces.

Recombination properties of dislocations in GaN

NASA Astrophysics Data System (ADS)

Yakimov, Eugene B.; Polyakov, Alexander Y.; Lee, In-Hwan; Pearton, Stephen J.

2018-04-01

The recombination activity of threading dislocations in n-GaN with different dislocation densities and different doping levels was studied using electron beam induced current (EBIC). The recombination velocity on a dislocation, also known as the dislocation recombination strength, was calculated. The results suggest that dislocations in n-GaN giving contrast in EBIC are charged and surrounded by a space charge region, as evidenced by the observed dependence of dislocation recombination strength on dopant concentration. For moderate (below ˜108 cm-2) dislocation densities, these defects do not primarily determine the average diffusion length of nonequilibrium charge carriers, although locally, dislocations are efficient recombination sites. In general, it is observed that the effect of the growth method [standard metalorganic chemical vapor deposition (MOCVD), epitaxial lateral overgrowth versions of MOCVD, and hydride vapor phase epitaxy] on the recombination activity of dislocations is not very pronounced, although the average diffusion lengths can widely differ for various samples. The glide of basal plane dislocations at room temperature promoted by low energy electron irradiation does not significantly change the recombination properties of dislocations.

Elbow Pain

MedlinePlus

... tear damage than are many other joints. Seek emergency care if you have: An obvious deformity in ... http://www.mayoclinic.org/symptoms/elbow-pain/basics/definition/SYM-20050874 . Mayo Clinic Footer Legal Conditions and ...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trishkina, L., E-mail: trishkina.53@mail.ru; Zboykova, N.; Koneva, N., E-mail: koneva@tsuab.ru

The aim of the investigation was the determination of the statistic description of dislocation distribution in each dislocation substructures component forming after different deformation degrees in the Cu-Al alloys. The dislocation structures were investigated by the transmission diffraction electron microscopy method. In the work the statistic description of distance distribution between the dislocations, dislocation barriers and dislocation tangles in the deformed Cu-Al alloys with different concentration of Al and test temperature at the grain size of 100 µm was carried out. It was established that the above parameters influence the dislocation distribution in different types of the dislocation substructures (DSS): dislocationmore » chaos, dislocation networks without disorientation, nondisoriented and disoriented cells, in the walls and inside the cells. The distributions of the distances between dislocations in the investigated alloys for each DSS type formed at certain deformation degrees and various test temperatures were plotted.« less

Modeling and 2-D discrete simulation of dislocation dynamics for plastic deformation of metal

NASA Astrophysics Data System (ADS)

Liu, Juan; Cui, Zhenshan; Ou, Hengan; Ruan, Liqun

2013-05-01

Two methods are employed in this paper to investigate the dislocation evolution during plastic deformation of metal. One method is dislocation dynamic simulation of two-dimensional discrete dislocation dynamics (2D-DDD), and the other is dislocation dynamics modeling by means of nonlinear analysis. As screw dislocation is prone to disappear by cross-slip, only edge dislocation is taken into account in simulation. First, an approach of 2D-DDD is used to graphically simulate and exhibit the collective motion of a large number of discrete dislocations. In the beginning, initial grains are generated in the simulation cells according to the mechanism of grain growth and the initial dislocation is randomly distributed in grains and relaxed under the internal stress. During the simulation process, the externally imposed stress, the long range stress contribution of all dislocations and the short range stress caused by the grain boundaries are calculated. Under the action of these forces, dislocations begin to glide, climb, multiply, annihilate and react with each other. Besides, thermal activation process is included. Through the simulation, the distribution of dislocation and the stress-strain curves can be obtained. On the other hand, based on the classic dislocation theory, the variation of the dislocation density with time is described by nonlinear differential equations. Finite difference method (FDM) is used to solve the built differential equations. The dislocation evolution at a constant strain rate is taken as an example to verify the rationality of the model.

Development and evaluation of a musculoskeletal model of the elbow joint complex

NASA Technical Reports Server (NTRS)

Gonzalez, Roger V.; Hutchins, E. L.; Barr, Ronald E.; Abraham, Lawrence D.

1993-01-01

This paper describes the development and evaluation of a musculoskeletal model that represents human elbow flexion-extension and forearm pronation-supination. The length, velocity, and moment arm for each of the eight musculotendon actuators were based on skeletal anatomy and position. Musculotendon parameters were determined for each actuator and verified by comparing analytical torque-angle curves with experimental joint torque data. The parameters and skeletal geometry were also utilized in the musculoskeletal model for the analysis of ballistic elbow joint complex movements. The key objective was to develop a computational model, guided by parameterized optimal control, to investigate the relationship among patterns of muscle excitation, individual muscle forces, and movement kinematics. The model was verified using experimental kinematic, torque, and electromyographic data from volunteer subjects performing ballistic elbow joint complex movements.

Extracorporeal shock wave treatment for chronic lateral epicondylitis (tennis elbow).

PubMed

Ho, C

2007-01-01

(1) Electrohydraulic, electromagnetic, or piezoelectric devices are used to translate energy into acoustic waves during extracorporeal shock wave treatment (ESWT) for chronic lateral epicondylitis (CLE) of the elbow (elbow tendonitis or tennis elbow). These waves may help to accelerate the healing process via an unknown mechanism. (2) Results from randomized controlled trials have been conflicting. Half of the studies showed statistically significant improvement in pain in the treatment group, and half of the studies had data showing no benefit over placebo for any measured outcomes. (3) Limited evidence shows that ESWT is cheaper than arthroscopic surgery, open surgery, and other conservative therapies, such as steroid infiltrations and physiotherapy, that continue for more than six weeks. (4) The lack of convincing evidence regarding its effectiveness does not support the use of ESWT for CLE.

Myositis ossificans traumatica causing ankylosis of the elbow.

PubMed

Kanthimathi, B; Udhaya Shankar, S; Arun Kumar, K; Narayanan, V L

2014-12-01

Myositis ossificans traumatica is an unusual complication following a muscle contusion injury. A significantly large myositic mass causing ankylosis of the elbow is even rarer. We report a 13-year-old boy who presented with a 14-month history of a fixed elbow with no movement and a palpable bony mass in the anterior aspect of the elbow. He had sustained significant trauma to the affected limb 1 month prior to onset of symptoms, which was managed by native massage and bandaging for 4 weeks. The clinicoradiological diagnosis was suggestive of myositis ossificans, and the myositic mass was completely excised. Histopathology revealed lamellar bone. The 2-year follow-up showed full function of the affected limb and no signs of recurrence. We report this case of clinical interest due to the unusually large myositic mass.

ACOEM practice guidelines: elbow disorders.

PubMed

Hegmann, Kurt T; Hoffman, Harold E; Belcourt, Roger M; Byrne, Kevin; Glass, Lee; Melhorn, J Mark; Richman, Jack; Zinni, Phillip; Thiese, Matthew S; Ott, Ulrike; Tokita, Kylee; Passey, Deborah Gwenevere; Effiong, Atim Cecelia; Robbins, Riann Bree; Ording, Julie A

2013-11-01

The American College of Occupational and Environmental Medicine has updated the treatment guidelines in its Elbow Disorders chapter through revision processes begun in 2006. This abbreviated version of that chapter highlights some of the evidence and recommendations developed. Comprehensive systematic literature reviews were accomplished with article abstraction, critiquing, grading, evidence table compilation, and guideline finalization by a multidisciplinary expert panel and extensive peer-review to develop evidence-based guidance. Consensus recommendations were formulated when evidence was lacking and often relied on analogy to other disorders for which evidence exists. A total of 108 high- or moderate-quality trials were identified for elbow disorders. Guidance has been developed for 13 major diagnoses and includes 270 specific recommendations. Quality evidence is now available to guide treatment for elbow disorders, particularly for lateral epicondylalgia.

Modal analysis of dislocation vibration and reaction attempt frequency

DOE PAGES

Sobie, Cameron; Capolungo, Laurent; McDowell, David L.; ...

2017-02-04

Transition state theory is a fundamental approach for temporal coarse-graining. It estimates the reaction rate for a transition processes by quantifying the activation free energy and attempt frequency for the unit process. To calculate the transition rate of a gliding dislocation, the attempt frequency is often obtained from line tension estimates of dislocation vibrations, a highly simplified model of dislocation behavior. This work revisits the calculation of attempt frequency for a dislocation bypassing an obstacle, in this case a self-interstitial atom (SIA) loop. First, a direct calculation of the vibrational characteristics of a finite pinned dislocation segment is compared tomore » line tension estimates before moving to the more complex case of dislocation-obstacle bypass. The entropic factor associated with the attempt frequency is calculated for a finite dislocation segment and for an infinite glide dislocation interacting with an SIA loop. Lastly, it is found to be dislocation length independent for three cases of dislocation-self interstitial atom (SIA) loop interactions.« less

Dynamics of threading dislocations in porous heteroepitaxial GaN films

NASA Astrophysics Data System (ADS)

Gutkin, M. Yu.; Rzhavtsev, E. A.

2017-12-01

Behavior of threading dislocations in porous heteroepitaxial gallium nitride (GaN) films has been studied using computer simulation by the two-dimensional discrete dislocation dynamics approach. A computational scheme, where pores are modeled as cross sections of cylindrical cavities, elastically interacting with unidirectional parallel edge dislocations, which imitate threading dislocations, is used. Time dependences of coordinates and velocities of each dislocation from dislocation ensembles under investigation are obtained. Visualization of current structure of dislocation ensemble is performed in the form of a location map of dislocations at any time. It has been shown that the density of appearing dislocation structures significantly depends on the ratio of area of a pore cross section to area of the simulation region. In particular, increasing the portion of pores surface on the layer surface up to 2% should lead to about a 1.5-times decrease of the final density of threading dislocations, and increase of this portion up to 15% should lead to approximately a 4.5-times decrease of it.

Computational Fluid Dynamic simulations of pipe elbow flow.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Homicz, Gregory Francis

2004-08-01

One problem facing today's nuclear power industry is flow-accelerated corrosion and erosion in pipe elbows. The Korean Atomic Energy Research Institute (KAERI) is performing experiments in their Flow-Accelerated Corrosion (FAC) test loop to better characterize these phenomena, and develop advanced sensor technologies for the condition monitoring of critical elbows on a continuous basis. In parallel with these experiments, Sandia National Laboratories is performing Computational Fluid Dynamic (CFD) simulations of the flow in one elbow of the FAC test loop. The simulations are being performed using the FLUENT commercial software developed and marketed by Fluent, Inc. The model geometry and meshmore » were created using the GAMBIT software, also from Fluent, Inc. This report documents the results of the simulations that have been made to date; baseline results employing the RNG k-e turbulence model are presented. The predicted value for the diametrical pressure coefficient is in reasonably good agreement with published correlations. Plots of the velocities, pressure field, wall shear stress, and turbulent kinetic energy adjacent to the wall are shown within the elbow section. Somewhat to our surprise, these indicate that the maximum values of both wall shear stress and turbulent kinetic energy occur near the elbow entrance, on the inner radius of the bend. Additional simulations were performed for the same conditions, but with the RNG k-e model replaced by either the standard k-{var_epsilon}, or the realizable k-{var_epsilon} turbulence model. The predictions using the standard k-{var_epsilon} model are quite similar to those obtained in the baseline simulation. However, with the realizable k-{var_epsilon} model, more significant differences are evident. The maximums in both wall shear stress and turbulent kinetic energy now appear on the outer radius, near the elbow exit, and are {approx}11% and 14% greater, respectively, than those predicted in the baseline calculation; secondary maxima in both quantities still occur near the elbow entrance on the inner radius. Which set of results better reflects reality must await experimental corroboration. Additional calculations demonstrate that whether or not FLUENT's radial equilibrium pressure distribution option is used in the PRESSURE OUTLET boundary condition has no significant impact on the flowfield near the elbow. Simulations performed with and without the chemical sensor and associated support bracket that were present in the experiments demonstrate that the latter have a negligible influence on the flow in the vicinity of the elbow. The fact that the maxima in wall shear stress and turbulent kinetic energy occur on the inner radius is therefore not an artifact of having introduced the sensor into the flow.« less

Preventing pressure ulcers

MedlinePlus

... Hips Spine Tailbone area Elbows Shoulders and shoulder blades Back of the head Ears Call your health ... your tailbone area Under your shoulders and shoulder blades Under your elbows Other tips are: DO NOT ...

Sports and performing arts medicine. 2. Shoulder and elbow overuse injuries in sports.

PubMed

Akuthota, Venu; Chou, Larry H; Drake, David F; Nadler, Scott F; Toledo, Santiago D

2004-03-01

This self-directed learning module discusses classic topics and highlights new advances in this area. This article discusses upper-limb sports injuries as part of a section of the study guide on sports and performing arts medicine in the Self-Directed Physiatric Education Program for practitioners and trainees in physical medicine and rehabilitation. This article uses case vignettes as a vehicle to elaborate on shoulder and elbow pain in the athlete. To discuss shoulder and elbow overuse injuries in sports.

Posterolateral rotatory instability from multiple steroids injections for tennis elbow: a case report.

PubMed

Chanlalit, Cholawish; Limsricharoen, Warodom

2013-01-01

This article reports the complication (lateral collateral ligament rupture) arising from improper numbers of steroids injections for the chronic lateral elbow pain (tennis elbow). Clinical sign and investigation with MRI confirmed a diagnosis of LCL rupture. In the present report, we describe the successful outcome of one year results in surgical debridement and lateral collateral ligament (LCL) reconstruction. A discussion of the proper conservative role for the chronic lateral epicondyalgia and the surgical decision to resolve this complication is also included.

The thrower's elbow.

PubMed

Patel, Ronak M; Lynch, T Sean; Amin, Nirav H; Calabrese, Gary; Gryzlo, Stephen M; Schickendantz, Mark S

2014-07-01

Overhead throwing activities expose the elbow to tremendous valgus stress, making athletes vulnerable to a specific constellation of injuries. Although baseball players, in particular pitchers, are the athletes affected most commonly, overhead throwing athletes in football, volleyball, tennis, and javelin tossing also are affected. The purpose of this review is to review the anatomy, biomechanics, pathophysiology, and treatment of elbow disorders related to overhead throwing athletes. Although focus is on management of ulnar collateral ligament injuries, all common pathologies are discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

Density of bunched threading dislocations in epitaxial GaN layers as determined using X-ray diffraction

NASA Astrophysics Data System (ADS)

Barchuk, M.; Holý, V.; Rafaja, D.

2018-04-01

X-ray diffraction is one of the most popular experimental methods employed for determination of dislocation densities, as it can recognize both the strain fields and the local lattice rotations produced by dislocations. The main challenge of the quantitative analysis of the dislocation density is the formulation of a suitable microstructure model, which describes the dislocation arrangement and the effect of the interactions between the strain fields from neighboring dislocations reliably in order to be able to determine the dislocation densities precisely. The aim of this study is to prove the capability of X-ray diffraction and two computational methods, which are frequently used for quantification of the threading dislocation densities from X-ray diffraction measurements, in the special case of partially bunched threading dislocations. The first method is based on the analysis of the dislocation-controlled crystal mosaicity, and the other one on the analysis of diffuse X-ray scattering from threading dislocations. The complementarity of both methods is discussed. Furthermore, it is shown how the complementarity of these methods can be used to improve the results of the quantitative analysis of bunched and thus inhomogeneously distributed threading dislocations and to get a better insight into the dislocation arrangement.

Interaction of 〈1 0 0〉 dislocation loops with dislocations studied by dislocation dynamics in α-iron

NASA Astrophysics Data System (ADS)

Shi, X. J.; Dupuy, L.; Devincre, B.; Terentyev, D.; Vincent, L.

2015-05-01

Interstitial dislocation loops with Burgers vector of 〈1 0 0〉 type are formed in α-iron under neutron or heavy ion irradiation. As the density and size of these loops increase with radiation dose and temperature, these defects are thought to play a key role in hardening and subsequent embrittlement of iron-based steels. The aim of the present work is to study the pinning strength of the loops on mobile dislocations. Prior to run massive Dislocation Dynamics (DD) simulations involving experimentally representative array of radiation defects and dislocations, the DD code and its parameterization are validated by comparing the individual loop-dislocation reactions with those obtained from direct atomistic Molecular Dynamics (MD) simulations. Several loop-dislocation reaction mechanisms are successfully reproduced as well as the values of the unpinning stress to detach mobile dislocations from the defects.

ESTIMATION OF FUNCTIONALS OF SPARSE COVARIANCE MATRICES.

PubMed

Fan, Jianqing; Rigollet, Philippe; Wang, Weichen

High-dimensional statistical tests often ignore correlations to gain simplicity and stability leading to null distributions that depend on functionals of correlation matrices such as their Frobenius norm and other ℓ r norms. Motivated by the computation of critical values of such tests, we investigate the difficulty of estimation the functionals of sparse correlation matrices. Specifically, we show that simple plug-in procedures based on thresholded estimators of correlation matrices are sparsity-adaptive and minimax optimal over a large class of correlation matrices. Akin to previous results on functional estimation, the minimax rates exhibit an elbow phenomenon. Our results are further illustrated in simulated data as well as an empirical study of data arising in financial econometrics.