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1

ARTHROSCOPIC INTERPOSITION ARTHROPLASTY OF THE FIRST CARPOMETACARPAL JOINT  

Microsoft Academic Search

First carpometacarpal joint arthritis is a common condition encountered by hand surgeons. Traditionally, surgical approaches have included arthrodesis, trapeziectomy or reconstructive arthroplasty techniques. Previously, we described a technique for arthroscopic debridement and interposition arthroplasty of the first carpometacarpal joint. Patients with Eaton stages II and III symptomatic first carpometacarpal joint arthritis recalcitrant to >6 months of non-operative therapy underwent arthroscopic

J. E. ADAMS; S. M. MERTEN; S. P. STEINMANN

2007-01-01

2

Thumb carpometacarpal arthroplasty with ligament reconstruction and interposition costochondral arthroplasty.  

PubMed

Background Thumb arthritis at the carpometacarpal (CMC) joint is one of the most common sites of arthritis, especially in women. Thumb arthroplasty is an effective method of relieving pain and improving function. Materials and Methods Qualitative and quantitative outcomes were assessed clinically and radiographically in 58 patients (66 thumbs) with thumb basal joint arthritis limited to the trapeziometacarpal joint, treated with hemiresection arthroplasty of the trapezium, flexor carpi radialis (FCR) ligament reconstruction, and allograft costochondral interposition graft. Description of Technique The thumb CMC joint arthroplasty is performed using an FCR tendon for ligament reconstruction combined with removal of the distal half of the trapezium, which is replaced with a life preserver-shaped spacer that is carved out of allograft cartilage. Results Results of the validated Disability of Arm, Shoulder, and Hand (DASH) questionnaire at a mean follow-up time of 56 months (range, 24-103 months) revealed that 90% of the patients had a high level of function with minimal symptoms. Important improvements in web space with increased palmar and radial abduction and grip and pinch strength measurements were observed. The trapeziometacarpal space had decreased 21% after surgery, while trapeziometacarpal subluxation was 14% compared with 21% before surgery. There was an inverse correlation between the loss of trapezial height and subluxation and clinical outcome. Conclusions The results of this study demonstrate that, although the preoperative trapezial height was not maintained, the reconstructed thumbs remained stable, with little subluxation and improved clinical outcomes. Level of Evidence IV, retrospective case series. PMID:24436820

Trumble, Thomas; Rafijah, Gregory; Heaton, Dennis

2013-08-01

3

The Modified Oblique Keller Capsular Interpositional Arthroplasty for Hallux Rigidus  

PubMed Central

Background: Hallux rigidus is a common problem characterized by localized osteoarthritis and limited range of motion of the hallux. First metatarsophalangeal joint arthrodesis has been the accepted procedure for the treatment of late-stage disease. Despite the success of arthrodesis, some patients object to the notion of eliminating motion at the metatarsophalangeal joint. For this reason, motion-sparing procedures such as the modified oblique Keller capsular interpositional arthroplasty have been developed. Methods: We compared a cohort of ten patients (ten toes) who had undergone the modified Keller arthroplasty with a group of twelve patients (twelve toes) who had undergone a first metatarsophalangeal joint arthrodesis at an average of sixty-three and sixty-eight months, respectively. Clinical outcomes were evaluated, and range of motion, great toe dynamometer strength, plantar pressures, and radiographs were assessed. Results: Clinical outcome differences existed between the groups, with the American Orthopaedic Foot and Ankle Society score being significantly higher for the arthroplasty group than for the arthrodesis group. The arthroplasty group had a mean of 54° of passive and 30° of active range of motion of the first metatarsophalangeal joint. The plantar pressure data revealed significantly higher pressures in the arthrodesis group under the great toe but not under the second metatarsal head. Conclusions: The modified oblique Keller capsular interpositional arthroplasty appears to be a motion-sparing procedure with clinical outcomes equivalent to those of arthrodesis, and it is associated with a more normal pattern of plantar pressures during walking. Level of Evidence: Therapeutic Level III. See Instructions to Authors for a complete description of levels of evidence. PMID:20720136

Mackey, R. Brian; Thomson, A. Brian; Kwon, Ohyun; Mueller, Michael J.; Johnson, Jeffrey E.

2010-01-01

4

Poor results after interpositional arthroplasty with fascia lata allograft for arthritis of the trapezio-metacarpal joint  

Microsoft Academic Search

Arthrodesis or autologous tendon interposition can relieve pain associated with arthritis of the carpo-metacarpal joint of\\u000a the first ray (CMC-I), but has its limitations. The aim of this study was to assess whether trapezium resection and fascia\\u000a lata allograft (Tutoplast) interposition is a good alternative. Thirty-eight such combined CMC-I arthroplasties in 36 patients\\u000a with a median age of 57 years and

F. J. C. van der Veen; S. D. Strackee; R. B. Karim; J. J. Hage

2007-01-01

5

Salvage reconstruction of failed interposition arthroplasty at the base of the thumb.  

PubMed

We present an operative procedure designed to revise a failed arthroplasty at the base of the thumb. This report describes a reliable operation that corrects residual instability and malignment which results in thumbs that are weak and painful despite a previous procedure. The operation has also been used as a primary procedure for arthritis of the trapeziometacarpal joint where instability and subluxation was a major component of the problem requiring joint reconstruction. The unique features of this procedure include a reinforced double-thickness tendon graft, a unique tendon anchor, and a fascia lata allograft spacer. Significant functional improvement is anticipated when joint reconstruction provides increased proximal stability. Pinch and grip measurements improve. Pain scores also diminish after the operation. Hand function and patient satisfaction can be substantially improved with revision arthroplasty when the initial operation has failed to provide a thumb that is mobile, stable, and pain free. The technical features of the procedure address reduction of malignment, restoring of anatomic balance, and secure fixation of the proximal apex of the thumb metacarpal which restores thumb reduction position and digital balance. PMID:23160558

Braun, Richard M; Rechnic, Mark; Shah, Kalpit N

2012-12-01

6

Gap Balancing versus Measured Resection Technique for Total Knee Arthroplasty  

Microsoft Academic Search

Multiple differing surgical techniques are currently utilized to perform total knee arthroplasty (TKA). We compared knee arthroplasties\\u000a performed using either a measured resection or gap balancing technique to determine if either operative technique provides\\u000a superior coronal plane stability as measured by assessment of the incidence and magnitude of femoral condylar lift-off. We\\u000a performed 40 TKA using a measured resection technique

Douglas A. Dennis; Richard D. Komistek; Raymond H. Kim; Adrija Sharma

2010-01-01

7

Gap Balancing vs. Measured Resection Technique in Total Knee Arthroplasty  

PubMed Central

A goal of total knee arthroplasty is to obtain symmetric and balanced flexion and extension gaps. Controversy exists regarding the best surgical technique to utilize to obtain gap balance. Some favor the use of a measured resection technique in which bone landmarks, such as the transepicondylar, the anterior-posterior, or the posterior condylar axes are used to determine proper femoral component rotation and subsequent gap balance. Others favor a gap balancing technique in which the femoral component is positioned parallel to the resected proximal tibia with each collateral ligament equally tensioned to obtain a rectangular flexion gap. Two scientific studies have been performed comparing the two surgical techniques. The first utilized computer navigation and demonstrated a balanced and rectangular flexion gap was obtained much more frequently with use of a gap balanced technique. The second utilized in vivo video fluoroscopy and demonstrated a much high incidence of femoral condylar lift-off (instability) when a measured resection technique was used. In summary, the authors believe gap balancing techniques provide superior gap balance and function following total knee arthroplasty. PMID:24605183

Daines, Brian K.

2014-01-01

8

First Metatarsophalangeal Joint Interpositional Arthroplasty Using a Meniscus Allograft for the Treatment of Advanced Hallux RigidusSurgical Technique and Short-term Results  

Microsoft Academic Search

Hallux rigidus is a progressive disorder of the first metatarsophalangeal (MTP) joint. The disorder is characterized by a loss of range of motion, degenerative changes, and pain within the joint. In later stages of the disease, the surgical procedure of choice is arthrodesis of the joint. Recently, salvage procedures of the first MTP joint using soft tissue interposition has gained

Eugene L. DelaCruz; Adam R. Johnson; Benjamin L. Clair

2011-01-01

9

Salvage options for flexor carpi radialis tendon disruption during ligament reconstruction and tendon interposition or suspension arthroplasty of the trapeziometacarpal joint.  

PubMed

Several techniques of thumb basilar joint arthroplasty depend on an intact flexor carpi radialis (FCR) tendon. There are situations, however, when the FCR tendon may be attenuated or iatrogenically injured, which make these techniques difficult or unfeasible. Familiarity with intraoperative salvage techniques in this setting is imperative. We present techniques for stabilizing the base of the thumb metacarpal when the FCR is deficient or injured. PMID:23928018

Jones, David B; Rhee, Peter C; Shin, Alexander Y; Kakar, Sanjeev

2013-09-01

10

Extension and flexion gap balancing and its correlation with alignment in navigated total knee arthroplasty.  

PubMed

Computer-assisted surgery was developed to improve the results of conventional total knee arthroplasty (TKA). The authors investigated the preoperative varus/valgus deformity influence on the production of balanced extension and flexion gaps using computer-assisted surgery. This study evaluated data from a prospective case series. A total of 132 patients (107 women and 25 men) underwent navigated TKA. Patients were divided into the following 3 groups according to the degree of the initial varus/valgus deformity: group 1, 0° to 3°; group 2, 3° to 9°; and group 3, greater than 9°. The final lower limb mechanical axis (LLMA) and the final flexion and extension gaps were measured. Knees exhibiting up to 3° of deviation on the frontal plane and a difference of up to 3 mm between the lateral and medial gaps were considered to be aligned and balanced, respectively. Average LLMA deviation decreased from 5.58° (± 4.80°) to 1.87° (± 1.66°). For knees with varus deviation, the percentage of balancing relative to the flexion gaps was 97.8% and that relative to the extension gap was 100% (P>.05). For knees with valgus deviation, the percentage of balancing relative to the flexion gaps was 95.1% and that relative to the extension gap was 97.6% (P>.05). Approximately 92% of the LLMA alignment was achieved in the group with varus deformity, whereas 71.4% was observed in the group with valgus deformity (P<.05). Computer-assisted TKA could attain proper flexion and extension balance regardless of coronal plane malalignment magnitude. Severe valgus and varus knees are more difficult to align using navigation. No difference was found in the balance of flexion or extension gaps in valgus or varus knees, independent of the severity. PMID:25102503

Debieux, Pedro; de Oliveira, José Renato Lemos Marques; Franciozi, Carlos Eduardo da Silveira; Kubota, Marcelo Seiji; Granata, Geraldo; Luzo, Marcus Vinícius Malheiros

2014-08-01

11

Hallux rigidus. Excisional arthroplasty.  

PubMed

The authors feel that capsular interposition arthroplasty can give predictable pain relief in carefully selected individuals with severe (grade III) hallux rigidus. Attention to the relative lengths of the first and second metatarsals, minimal shortening of the proximal phalanx, and use of the dorsal capsule and EHB tendon as an interposition all contribute to good to excellent objective and subjective results. Approximately 30% of patients undergoing this procedure experience some degree of transfer metatarsalgia postoperatively and probably require orthoses for sports. The authors feel that this operation presents a reasonable alternative to many patients who are candidates for an arthrodesis of the first MTP joint for advanced degenerative disease. PMID:11232402

Hamilton, W G; Hubbard, C E

2000-09-01

12

21 CFR 872.3970 - Interarticular disc prosthesis (interpositional implant).  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Interarticular disc prosthesis (interpositional implant). 872... § 872.3970 Interarticular disc prosthesis (interpositional implant). (a) Identification. An interarticular disc prosthesis (interpositional implant) is...

2010-04-01

13

Flexion gap configuration in total knee arthroplasty following high tibial osteotomy  

Microsoft Academic Search

Previous reports have described the potentially compromising effect of a high tibial osteotomy (HTO) on the results of a subsequent total knee arthroplasty (TKA). Although the reasons are not clear, some authors reported problems in soft-tissue balancing. In a prospective study, 22 patients with an average interval of 5.8 years after closed-wedge HTO were operated for TKA. All operations were

H. Bäthis; L. Perlick; M. Tingart; C. Lüring; C. Perlick; J. Grifka

2004-01-01

14

Colonic interposition and supercharge for esophageal reconstruction  

Microsoft Academic Search

Aims  We evaluated the techniques of colonic interposition and supercharge for esophageal reconstruction and discussed the main\\u000a considerations related to these procedures.\\u000a \\u000a \\u000a \\u000a Patients and methods  In this study, we performed 51 esophageal reconstructions using colonic interposition. Twenty-eight of the 51 patients had\\u000a synchronous or allochronic gastric malignancy. We selected colonic interposition for high anastomosis in 11 patients and also\\u000a for esophageal bypass

Yasuhiro Shirakawa; Yoshio Naomoto; Kazuhiro Noma; Kazufumi Sakurama; Toshio Nishikawa; Tetsuji Nobuhisa; Masahiko Kobayashi; Takaomi Okawa; Shinya Asami; Tomoki Yamatsuji; Minoru Haisa; Junji Matsuoka; Motohiko Hanazaki; Kiyoshi Morita; Takao Hiraki; Noriaki Tanaka

2006-01-01

15

Salvage of first metatarsophalangeal joint arthroplasty complications.  

PubMed

There are two broad categories of surgical techniques for first metatarsophalangeal joint arthroplasty. Resection arthroplasty is a resection of the base of the proximal phalanx with or without an interposition graft of capsule or adjacent tendon. The second technique involves a partial or complete joint replacement. The primary indication for these procedures is first metatarsophalangeal joint pain caused by arthritic change. The salvage surgical options for failed metatarsophalangeal joint arthoplasty are directed toward decreasing or eliminating the symptoms arising from the complications of these procedures. PMID:12760573

Baumhauer, Judith F; DiGiovanni, Benedict F

2003-03-01

16

Ligament reconstruction tendon interposition with mersilene augmentation.  

PubMed

Many surgical procedures have been described for the treatment of thumb basilar joint osteoarthritis. Augmentation of the standard ligament reconstruction tendon interposition procedure with the use of a Mersilene suture tape suspension-plasty, to recreate the stability provided by the anterior oblique ligament and increase pinch strength, will be described. Satisfaction with this procedure was evaluated through surveys completed by patients. In addition, independent physical assessments were performed to demonstrate stability, range of motion, and strength. PMID:21358518

Stein, Andrew J; Schofield, Jennifer L; Marsh, Mike; Paulo, Jerry

2011-03-01

17

Relationship between joint gap difference and range of motion in total knee arthroplasty: a prospective randomised study between different platforms  

Microsoft Academic Search

The objective of this study was to investigate the range of motion (ROM) of the knee before and four years after total knee\\u000a arthroplasty (TKA) with a mobile or fixed type of platform and to prospectively evaluate whether there was a difference in\\u000a ligament balance between the platform types. The subjects were 68 patients involving 76 joints. The mobile type

Hiroshi Higuchi; Kazuhisa Hatayama; Masaki Shimizu; Atsushi Kobayashi; Tsutomu Kobayashi; Kenji Takagishi

2009-01-01

18

Gastric interposition following transhiatal esophagectomy: CT evaluation  

SciTech Connect

Transhiatal esophagectomy without thoracotomy (THE) but with gastric interposition results in less morbidity and mortality than standard transpleural esophagectomy with thoracotomy. Barium examination has been the primary radiographic study following THE for detecting postoperative complications. The authors reviewed computed tomography (CT) scans of 21 patients who had undergone THE and correlated CT appearance with clinical status and with findings of the barium studies. Local mediastinal recurrent neoplasm was detected by CT in seven patients; barium study within 2 weeks of the CT scan failed to detect tumor recurrence in three of these patients. CT is the modality of choice for detecting locally recurrent neoplasm and distant metastases following THE and may also be helpful in patients with postoperative mediastinal abscess. Normal mediastinal CT anatomy after esophagectomy is reviewed in order to warn against pitfalls in scan interpretation.

Gross, B.H.; Agha, F.P.; Glazer, G.M.; Orringer, M.B.

1985-04-01

19

Interposition vein graft for giant coronary aneurysm repair  

NASA Technical Reports Server (NTRS)

Coronary aneurysms in adults are rare. Surgical treatment is often concomitant to treating obstructing coronary lesions. However, the ideal treatment strategy is poorly defined. We present a case of successful treatment of a large coronary artery aneurysm with a reverse saphenous interposition vein graft. This modality offers important benefits over other current surgical and percutaneous techniques and should be considered as an option for patients requiring treatment for coronary aneurysms.

Firstenberg, M. S.; Azoury, F.; Lytle, B. W.; Thomas, J. D.

2000-01-01

20

Transport distraction osteogenesis as a method of reconstruction of the temporomandibular joint following gap arthroplasty for post-traumatic ankylosis in children: a clinical and radiological prospective assessment of outcome.  

PubMed

This clinical and radiographic study investigated the use of transport distraction osteogenesis in unilateral temporomandibular joint (TMJ) ankylosis patients. Six patients aged between 4 and 8 years were selected for the study; the mean preoperative maximal inter-incisal opening (MIO) was 3.5mm without lateral and protrusive mandibular movements. The ankylotic mass along with the posterior border of the ascending ramus was exposed via 'lazy-S' incision. A gap arthroplasty was performed, followed by a 'reverse L' osteotomy on the posterior border of the ramus. In-house manufactured extraoral distraction devices were used for this prospective study. Follow-up clinical and radiographic evaluation was carried out for 13-27 months after completion of the activation period. After a mean follow-up of 19 months, the mean MIO was 29.1mm and the lateral and protrusive movements changed from none to slight. Cone beam computed tomography images of all patients showed remodelled neocondyle created by transport distraction osteogenesis with no statistically significant differences observed for average cancellous bone density, trabecular number, and trabecular spacing between the neocondyle of the operated side (test) and the condyle of the non-operated side (control). Neocondyle formation by transport distraction osteogenesis using the in-house distraction device is a promising treatment option for TMJ reconstruction in ankylosis patients. PMID:24016549

Bansal, V; Singh, S; Garg, N; Dubey, P

2014-02-01

21

Patellofemoral arthroplasty.  

PubMed

Patellofemoral arthroplasty remains controversial, primarily due to the high failure rates reported with early implants. Several case series have been published over the years, which describe the results with various first- and second-generation implants. The purpose of this work was to summarize results published up to now and identify common themes for implants, surgical techniques, and indications. First-generation resurfacing implants had relatively high failure rates in the medium term. Second-generation implants, with femoral cuts based on TKA designs, have yielded more promising medium-term results. The surgical indications are quite specific and must be chosen carefully to minimize poor results. Short-term complications are generally related to patellar maltracking, while long-term complications are generally related to progression of osteoarthritis in the tibiofemoral joint. Implant loosening and polyethylene wear are rare. Overall, recent improvements in implant design and surgical techniques have resulted in better short- and medium-term results. But more work is required to assess the long-term outcomes of modern implant designs. PMID:24412044

Lustig, S

2014-02-01

22

Full thickness cartilage palisade tympanoplasty with malleus interposition: a study of the long term results.  

PubMed

The aim of this retrospective study is to review long term results of full-thickness cartilage palisade tympanoplasty (FTCPT) with malleus head interposition performed on 51 patients (56 ears); 36 women and 15 men (7-73 years, 44 years average). The pathology of ears which encourages this technique of tympanoplasty is presented. On average 12 years after surgery we have elaborated anatomic and functional results. Anatomic results were categorized based on empiric evaluation of the new tympanic membrane status: 40 (71%) tympanic membranes without anatomic irregularities, 14 (25%) with irregularities and 2 (4%) with secondary perforation. Functional results (tonal audiogram) are based on pure tone average air-bone gap (PTA-ABG) at 4 frequencies. Main functional results of 51 ears (51 audiograms performed): pre- and post-operative average PTA-ABGs were 27.07 +/- 9.98 and 10.77 +/- 7.85 dB (t = 10.36; p < 0.001). In the group of ears with a tympanic membrane with no anatomic irregularities, pre- and post-operative average PTA-ABGs were 27.30 +/- 10.56 and 10.82 +/- 8.33 dB (t = 8.09; p < 0.001). In the group of ears with cartilage resorption, pre- and post-operative PTA-ABGs were 24.92 +/- 8.19 and 9.33 +/- 6.58 dB (t = 6.21; p < 0.001). The differences between the two groups are irrelevant. Postoperative PTA-ABG values of ears after first surgery (N = 34) and revision surgery (N = 17) was significantly different (8.75 +/- 5.75 and 15.16 +/- 9.62 dB) (t = 2.60; p = 0.016). In spite of the thickness of the new tympanal membrane, FTCPT is a successful technique for solving advanced ear pathology. PMID:24851631

Velepic, Marko M; Manestar, Dubravko; Starcevi?, Radan; Velepic, Barbara Cesnik; Velepic, Sanja Zubovi?; Linsak, Zeljko

2014-03-01

23

Prevention of Frey syndrome with superficial temporal fascia interpositioning: a retrospective study.  

PubMed

Frey syndrome (FS) is a commonly documented postoperative complication following parotidectomy. The aim of this study was to clinically evaluate the efficacy of superficial temporal fascia (STF) as interpositioning barrier between the overlying skin flap and the parotid bed for the prevention of FS following superficial parotidectomy. A retrospective study was designed involving a population of patients from a single institution who underwent superficial parotidectomy for parotid tumours and refractory chronic sialadenitis from 2008 to 2011. Forty-eight cases were identified and divided into two groups: group I (n=25) had undergone STF interpositioning between the skin flap and the parotid bed after extending the modified Blair's incision in the temporal region, and group II (n=23) had undergone a superficial parotidectomy using the modified Blair's incision without any interpositioning. In group I, one of 25 cases (4%) developed mild FS; in group II, nine of 23 cases (39.1%) developed FS of varying severity. There were no cases of permanent facial palsy in either group. Alopecia along the temporal extension of the incision line was imperceptible in all group I cases. The use of an STF interpositioning barrier between the overlying skin flap and the parotid bed is a safe and effective procedure for the prevention of FS following superficial parotidectomy. PMID:24461587

Sharma, Rohit

2014-04-01

24

Treatment of radioulnar synostosis by radical excision and interposition of a radial forearm adipofascial flap.  

PubMed

A patient had radical excision of type II diaphyseal radioulnar synostosis and interposition of a radial forearm adipofascial flap. Neither adjuvant nonsteroidal anti-inflammatory medications nor radiation therapy were used. Three years after surgery the patient showed 90 degrees of pronation and 90 degrees of supination without any evidence of recurrence. PMID:15576229

Jones, Neil F; Esmail, Adil; Shin, Eon K

2004-11-01

25

Application of a wire-guided side-viewing duodenoscope in total esophagectomy with colonic interposition  

PubMed Central

Therapeutic endoscopic retrograde cholangiopancreatography (ERCP) is the mainstay treatment for bile duct disease. The procedure is difficult per se, especially when a side-viewing duodenoscope is used, and when the patient has altered anatomical features, such as colonic interposition. Currently, there is no consensus on the standard approach for therapeutic ERCP in patients with total esophagectomy and colonic interposition. We describe a novel treatment design that involves the use of a side-viewing duodenoscope to perform therapeutic ERCP in patients with total esophagectomy and colonic interposition. A gastroscope was initially introduced into the interposed colon and a radio-opaque standard guidewire was advanced to a distance beyond the papilla of Vater, before the gastroscope was withdrawn. A side-viewing duodenoscope was then introduced along the guidewire under fluoroscopic guidance. After cannulation into the papilla of Vater, endoscopic retrograde cholangiography (ERC) revealed a filling defect (maximum diameter: 15 cm) at the distal portion of the common bile duct (CBD). This defect was determined to be a stone, which was successfully retrieved by a Dormia basket after complete sphincterotomy. With this treatment design, it is possible to perform therapeutic ERCP in patients with colonic interposition, thereby precluding the need for percutaneous drainage or surgery. PMID:21483642

Yii, Chin-Yuan; Chou, Jen-Wei; Peng, Yen-Chun; Chow, Wai-Keung

2011-01-01

26

Mortality after shoulder arthroplasty.  

PubMed

One year post-operative mortality among patients with primary elective total shoulder arthroplasty (ETSA) and traumatic shoulder arthroplasty (TSA) were compared to the general population of a large healthcare system. Standardized mortality ratios (SMRs) and 95% confidence intervals (CIs) were calculated. 614 ETSA patients, 1.0% one year mortality, and 168 TSA patients, 5.4% mortality rate, were evaluated. Patients with ETSA (SMR = 0.4, 95% CI 0.1-0.7) had lower odds of mortality than expected, while patients with TSA (SMR = 1.8, 95% CI 0.6-3.0) did not have higher than expected odds of mortality compared to the reference population. Understanding excess mortality following shoulder arthroplasty surgery allows providers to evaluate current practices and identify ways to optimize patients prior to surgery. PMID:24836652

Inacio, Maria C S; Dillon, Mark T; Miric, Alexander; Anthony, Faith; Navarro, Ronald A; Paxton, Elizabeth W

2014-09-01

27

Successful delayed nose replantation following a dogbite: arterial and venous microanastomosis using interpositional vein grafts.  

PubMed

The nose is one of the most important aesthetic units of the face. Following traumatic amputation, although technically very challenging, replantation is undoubtedly the procedure of choice. We present the first successful replantation of a partially amputated nose subjected to an ischaemic time of over 12 h. The injury was sustained following a dog-bite and inter-positional vein grafts were used to re-establish both arterial and venous blood flow. PMID:24559733

Gilleard, Onur; Smeets, Laurent; Seth, Rohit; Jones, Martin E

2014-07-01

28

Retrograde stapling of a free cervical jejunal interposition graft: a technical innovation and case report  

PubMed Central

Background Free jejunal interposition is a useful technique for reconstruction of the cervical esophagus. However, the distal anastomosis between the graft and the remaining thoracic esophagus or a gastric conduit can be technically challenging when located very low in the thoracic aperture. We here describe a modified technique for retrograde stapling of a jejunal graft to a failed gastric conduit using a circular stapler on a delivery system. Case presentation A 56 year-old patient had been referred for esophageal squamous cell carcinoma at 20 cm from the incisors. On day 8 after thoracoabdominal esophagectomy with gastric pull-up, an anastomotic leakage was diagnosed. A proximal-release stent was successfully placed by gastroscopy and the patient was discharged. Two weeks later, an esophagotracheal fistula occurred proximal to the esophageal stent. Cervical esophagostomy was performed with cranial closure of the gastric conduit, which was left in situ within the right hemithorax. Three months later, reconstruction was performed using a free jejunal interposition. The anvil of a circular stapler (Orvil®, Covidien) was placed transabdominally through an endoscopic rendez-vous procedure into the gastric conduit. A free jejunal graft was retrogradely stapled to the proximal end of the conduit. Microvascular anastomoses were performed subsequently. The proximal anastomosis of the conduit was completed manually after reperfusion. Conclusions This modified technique allows stapling of a jejunal interposition graft located deep in the thoracic aperture and is therefore a useful method that may help to avoid reconstruction by colonic pull-up and thoracotomy. PMID:25319372

2014-01-01

29

Robotic total hip arthroplasty.  

PubMed

Modern total hip replacement is typically effective and durable, but early failures do occur. Component position influences functional outcome, durability, and risk of complications. Surgical robotics provides the detail-oriented surgeon with a robust tool to optimize the accuracy and precision of total hip arthroplasty, with the potential to minimize risk of mechanical failure. This article describes efficient workflows for using surgical robotics to optimize surgical precision without increasing surgical complexity. PMID:25199417

Hepinstall, Matthew S

2014-10-01

30

Interposition of Ileal J-Pouch for Rectum Reconstruction in Dog  

PubMed Central

Background: The gold standard of the management of rectal cancer in the middle and lower parts is low anterior resection with coloanal anastomosis. About 50% of the patients undergoing this procedure might experience some complications because of the low capacity of the neorectum. The aim of this study was to evaluate ileal J-pouch interposition as a neorectum between the anal canal and the remaining colon in comparison to coloanal anastomosis and transverse coloplasty. Methods: Twelve dogs, weighing 23-27 kg, were divided into three groups. After laparotomy, the volume of the primary rectum was measured so that it could be compared with that of the neorectum at the end of the study. After rectal resection in Group A, the colon was directly anastomosed to the anus. In Group B, a 5-cm longitudinal incision was made 2 cm proximal to the anastomosis and was sutured transversely (coloplasty). In Group C, a 5-cm ileal J-pouch was interposed between the colon and anus. After 8 weeks, the neorectum was evaluated for volume, radiology, and pathology. Results: All the samples were alive until the end of the study. The healing of the anastomotic lines was acceptable (pathologically) in all. The mean volume expansion was 20.9% in Group A, 21.7% in Group B, and 118.2% in Group C, with the latter being significantly higher than that of the other groups (P=0.03). Colon J-pouch and coloplasty after proctectomy in some situations have not been performable. This study evaluated the performance of ileal J-pouch interposition. Conclusion: This study showed that ileal J-pouch interposition might produce an acceptable reservoir function and that it seems feasible and safe in selected cases. PMID:24644380

Ghahramani, Leila; Yazdani, Saeed; Derakhshani, Saeed; Rezaianzadeh, Abbas; Jalli, Reza; Geramizadeh, Bita; Safarpour, Ali Reza; Rahimikazerooni, Salar; Hosseini, Seyed Vahid

2014-01-01

31

Swirling flow pattern in a non-planar model of an interposition vein cuff anastomosis.  

PubMed

One of the main causes of long-term failure of ePTFE grafts is the development of anastomotic intimal hyperplasia which leads to graft thrombosis. Experimental studies with bypass grafts have shown an inverse relationship between mean wall shear stress and intimal hyperplasia. The geometry of the anastomosis has a strong influence on the flow pattern and wall shear stress distribution. The aim of this in vitro study was to investigate the influence of non-planarity in a model of a distal anastomosis with interposition vein cuff, an anastomosis configuration that is increasingly being used because of improved clinical results. Laser Doppler anemometer measurements were carried out in silicone rubber models of interposition vein cuff anastomoses with planar and non-planar inflow. The pulsatile flow waveforms were typical of those found in femoro-infrapopliteal bypass. Axial and radial velocities were measured in the proximal and distal outflow segments. As expected a symmetrical helical flow pattern (Dean flow) was evident in the planar model. The model with non-planar inflow, however, gave rise to swirling flow in both the distal and proximal artery outflow segments for during the systolic phase. In patients, the anastomosis is usually non-planar. Since the configuration depends in part upon the tunnelling of the graft, this may be altered to some extent. Non-planar anastomotic configurations induce a swirling flow pattern, which may normalise wall shear stress, thereby potentially reducing intimal hyperplasia. PMID:15921948

How, T V; Fisher, R K; Brennan, J A; Harris, P L

2006-01-01

32

Early Attempts at Hip Arthroplasty  

PubMed Central

Over the last three centuries, treatment of hip arthritides has evolved from rudimentary surgery to modern total hip arthroplasty (THA), which is considered one of the most successful surgical interventions ever developed. We here review the history of the early hip arthroplasty procedures for hip arthritis that preceded Charley total hip arthroplasty. An evaluation of such past enterprises is relevant, and reminds us of the ephemeral nature of human industriousness, and how medical research and procedures are not isolated developments, but correlate to the social, economical, and cultural framework of their time. PMID:16089067

Gomez, Pablo F; Morcuende, Jose A

2005-01-01

33

Knee Arthroplasty: Disabilities in Comparison to the General Population and to Hip Arthroplasty Using a  

E-print Network

Knee Arthroplasty: Disabilities in Comparison to the General Population and to Hip Arthroplasty Handicap, Paris, France Abstract Background: Knee arthroplasty is increasing exponentially due to the aging over two years in people with knee arthroplasty to that in the general population. A secondary

Paris-Sud XI, Université de

34

Clinical results of patellofemoral arthroplasty.  

PubMed

Isolated patellofemoral arthritis can be a disabling condition that can be challenging to treat. Patients with symptoms recalcitrant to conservative measures are considered for total or partial knee arthroplasty. This retrospective study reports the results of patellofemoral arthroplasty at a single center using a variety of implant designs. Thirty patients (37 knees) with isolated patellofemoral disease treated with patellofemoral arthroplasty with a minimum of one year follow-up were evaluated. The majority of patients were female (83%) and the underlying diagnosis was osteoarthritis in 98% of knees. Reported follow-up averaged 31 months. Average Knee Society Pain, Functional, and Clinical Scores improved from pre-op to most recent follow-up. Two complications (5.4%) required intervention. One patient was converted to a total knee arthroplasty secondary to patella instability. PMID:23790605

Morris, Michael J; Lombardi, Adolph V; Berend, Keith R; Hurst, Jason M; Adams, Joanne B

2013-10-01

35

Total disk arthroplasty.  

PubMed

Spinal fusion remains the gold standard for surgical management of instability and mechanical low back or neck pain. However, even in carefully selected patients, successful clinical results can be difficult to achieve. Reasons for failure include pseudarthrosis and adjacent spine segment disease. The theoretic advantages of removing the painful disk while preserving motion have led to increasing interest in total disk arthroplasty. Although disk replacements have been implanted in Europe for decades, the procedure is relatively new in the United States. Recently, two artificial disks for symptomatic lumbar degenerative disk disease have been approved by the US Food and Drug Administration; several others are undergoing clinical trials. Short-term studies demonstrate similar clinical improvements for both disk replacements and fusion procedures at up to 2-year follow-up. Issues requiring further research include optimal design specifications, potential complications, and appropriate patient selection. Consequently, the long-term benefit of total disk arthroplasty over fusion for the treatment of axial low back or neck pain remains to be determined. PMID:17148618

Lin, Eric L; Wang, Jeffrey C

2006-12-01

36

The failed first metatarsophalangeal joint implant arthroplasty.  

PubMed

Chronic pain in a first metatarsophalangeal implant arthroplasty can be early or late, and may be due to infection or implant failure. Although excisional arthroplasty can be considered, the most predictable result will come from arthrodesis. Conversion of a failed implant arthroplasty to fusion will usually require structural bone graft, with slower healing times than primary fusion. PMID:25129347

Greisberg, Justin

2014-09-01

37

Functional assessment of colonic interposition with 99Tcm-labeled milk  

SciTech Connect

A prospective study was performed to evaluate the use of radionuclide imaging in the assessment of patients who have undergone esophageal reconstruction. Dynamic radionuclide imaging was performed on ten patients aged 11 months to 11 years who had undergone colon interposition via the normal esophageal route for esophageal atresia. Patients were considered clinically unsatisfactory if at the time of imaging feeding was troubled, or if weight gain had fallen to below the third centile before operation and remained below after operation. Each patient underwent erect imaging with a small milk feed labeled with 10 to 20 MBq (250 to 500 muCi) 99Tcm DTPA adjusted according to body surface area; supine studies were subsequently performed on five patients. All five clinically unsatisfactory patients showed conduit emptying delayed beyond 45 minutes and/or spontaneous reflux, significantly different from the clinically satisfactory patients (X2 = 6.4, P less than .02). Conduit complications were subsequently identified in three of the five clinically unsatisfactory patients. Radionuclide imaging with radiolabeled milk was found to be well tolerated, and obtained results that were clinically useful. These results suggest that dynamic radionuclide imaging can be more widely applied in the assessment of esophageal substitutes.

Sutton, R.; Sutton, H.; Ackery, D.M.; Freeman, N.V. (Southampton General Hospital (England))

1989-09-01

38

Clinical and radiological results following cervical arthroplasty  

Microsoft Academic Search

Summary  \\u000a Background. This was a retrospective study of clinical and radiological results of cervical arthroplasty using the Bryan cervical disc\\u000a prosthesis to evaluate the efficacy of arthroplasty in clinical applications.\\u000a \\u000a \\u000a Methods. A total of 46 patients underwent arthroplasty of a single level using the Bryan disc prosthesis. Clinical outcome was assessed\\u000a using the visual analogue scale (VAS) and the neck

D. H. Yoon; S. Yi; H. C. Shin; K. N. Kim; S. H. Kim

2006-01-01

39

A flow visualization model of duodenogastric reflux after esophagectomy with gastric interposition  

PubMed Central

Background Our goal was to verify surgical factors that affect duodenogastric reflux (DGR) after esophagectomy through the use of a flow visualization model that would mimic an intrathoracic gastric tube. Methods Transparent gastric tube models for different routes (retrosternal space [RS] and posterior mediastinum [PM]) were fabricated. Various distal pressures were applied to the experimental model filled with water, and the flow was recorded with a high-speed camera. The volume and maximum height of the refluxate through the pylori of two different sizes (7.5 mm, 15 mm) in two different postures (upright, semi-Fowler) was measured by analyzing the video clips. Results For the large pylorus setting, when the pressures of 20, 30, and 40 mmHg were applied in the upright position, the volumes of the refluxate in the RS/PM tubes were 87.7?±?1.1/96.4?±?1.7 mL, 150.8?±?1.1/158.0?±?3.2 mL, and 156.8?±?3.3/198.0?±?4.7 mL (p?interposition or pyloric drainage procedure, or both, is associated with high reflux of duodenal contents. PMID:24067071

2013-01-01

40

Mycobacterium chelonae infection following a total knee arthroplasty  

Microsoft Academic Search

Infection following total knee arthroplasty is a major cause of implant failure, with an incidence of infections between 1 and 12%. Although there have been no previously reported cases of infection with Mycobacterium chelonae following total knee arthroplasty, this mycobacterium appears to be a potential pathogen in arthroplasty. When infection following total knee arthroplasty is evident but standard cultures come

Maya Pring; Donald G. Eckhoff

1996-01-01

41

Training a Sophisticated Microsurgical Technique: Interposition of External Jugular Vein Graft in the Common Carotid Artery in Rats  

PubMed Central

Neointimal hyperplasia is one the primary causes of stenosis in arterialized veins that are of great importance in arterial coronary bypass surgery, in peripheral arterial bypass surgery as well as in arteriovenous fistulas.1-5 The experimental procedure of vein graft interposition in the common carotid artery by using the cuff-technique has been applied in several research projects to examine the aetiology of neointimal hyperplasia and therapeutic options to address it. 6-8 The cuff prevents vessel anastomotic remodeling and induces turbulence within the graft and thereby the development of neointimal hyperplasia. Using the superior caval vein graft is an established small-animal model for venous arterialization experiment.9-11 This current protocol refers to an established jugular vein graft interposition technique first described by Zou et al., 9 as well as others.12-14 Nevertheless, these cited small animal protocols are complicated. To simplify the procedure and to minimize the number of experimental animals needed, a detailed operation protocol by video training is presented. This video should help the novice surgeon to learn both the cuff-technique and the vein graft interposition. Hereby, the right external jugular vein was grafted in cuff-technique in the common carotid artery of 21 female Sprague Dawley rats categorized in three equal groups that were sacrificed on day 21, 42 and 84, respectively. Notably, no donor animals were needed, because auto-transplantations were performed. The survival rate was 100 % at the time point of sacrifice. In addition, the graft patency rate was 60 % for the first 10 operated animals and 82 % for the remaining 11 animals. The blood flow at the time of sacrifice was 8±3 ml/min. In conclusion, this surgical protocol considerably simplifies, optimizes and standardizes this complicated procedure. It gives novice surgeons easy, step-by-step instruction, explaining possible pitfalls, thereby helping them to gain expertise fast and avoid useless sacrifice of experimental animals. PMID:23168988

Schleimer, Karina; Grommes, Jochen; Greiner, Andreas; Jalaie, Houman; Kalder, Johannes; Langer, Stephan; Koeppel, Thomas A.; Jacobs, Michael; Kokozidou, Maria

2012-01-01

42

Application of Hemi-Hip Joint Arthroplasty  

Microsoft Academic Search

Total hip replacement and hip resurfacing arthroplasty are two popular methods for curing the diseases of hip joints to date. While the technology can be considered to be mature, there are still some problems in practice. So, another method, hemi-hip joint arthroplasty, was introduced in this paper. The structure and materials of the prothesis, its experiments in vitro and the

Lan Chen; Mingzhao Chen; Lantian Chen; Ming Hu; Yiwang Bao

2008-01-01

43

Hip Resurfacing Arthroplasty and Perioperative Blood Testing  

PubMed Central

It is standard practice in many institutions to routinely perform preoperative and postoperative haemoglobin level testing in association with hip joint arthroplasty procedures. It is our observation, however, that blood transfusion after uncomplicated primary hip arthroplasty in healthy patients is uncommon and that the decision to proceed with blood transfusion is typically made on clinical grounds. We therefore question the necessity and clinical value of routine perioperative blood testing about the time of hip resurfacing arthroplasty. We present analysis of perioperative blood tests and transfusion rates in 107 patients undertaking unilateral hybrid hip resurfacing arthroplasty by the senior author at a single institution over a three-year period. We conclude that routine perioperative testing of haemoglobin levels for hip resurfacing arthroplasty procedures does not assist in clinical management. We recommend that postoperative blood testing only be considered should the patient demonstrate clinical signs of symptomatic anaemia or if particular clinical circumstances necessitate. PMID:25349744

Smith, Ian

2014-01-01

44

[Axial correction in knee revision arthroplasty].  

PubMed

Implant malalignment is a major cause for early loosening, increased wear, painful limitation of motion, and patient dissatisfaction in total knee arthroplasty. Validated diagnostic algorithms and a deeper understanding of the pathological mechanisms underlying functional deficits and pain resulting from malalignment explain the increasing number of revision operations on unloosened prostheses, which are now nearly as common as revisions for implant loosening. Common reasons are component malpositioning are a shifted joint line, or a non-physiological patella position. The success of any revision procedure basically depends on: (1) correct component positioning, (2) equal and symmetrical flexion and extension gaps, (3) restoration of joint line, and (4) a physiological patella height. The adequate grade of implant constraint has to be determined intra-operatively. A higher loosening rate of constrained implants as well as increased wear and painful limitation of motion in case of instability have to be taken into account. In the present work, a diagnostic and therapeutic algorithm for malalignment of knee prostheses is presented. PMID:16362140

Perka, C; Tohtz, S; Matziolis, G

2006-02-01

45

Protein kinases display minimal interpositional dependence on substrate sequence: potential implications for the evolution of signalling networks  

PubMed Central

Characterization of in vitro substrates of protein kinases by peptide library screening provides a wealth of information on the substrate specificity of kinases for amino acids at particular positions relative to the site of phosphorylation, but provides no information concerning interdependence among positions. High-throughput techniques have recently made it feasible to identify large numbers of in vivo kinase substrates. We used data from experiments on the kinases ATM/ATR and CDK1, and curated CK2 substrates to evaluate the prevalence of interactions between substrate positions within a motif and the utility of these interactions in predicting kinase substrates. Among these data, evidence of interpositional sequence dependencies is strikingly rare, and what dependency exists does little to aid in the prediction of novel kinase substrates. Significant increases in the ability of models to predict kinase–substrate specificity beyond position-independent models must come largely from inclusion of elements of biological and cellular context, rather than further analysis of substrate sequences alone. Our results suggest that, evolutionarily, kinase substrate fitness exists in a smooth energetic landscape. Taken with results from others indicating that phosphopeptide-binding domains do exhibit interpositional dependence, our data suggest that incorporation of new substrate molecules into phospho-signalling networks may be rate-limited by the evolution of suitability for binding by phosphopeptide-binding domains. PMID:22889908

Joughin, Brian A.; Liu, Chengcheng; Lauffenburger, Douglas A.; Hogue, Christopher W. V.; Yaffe, Michael B.

2012-01-01

46

Cervical disc arthroplasty: Pros and cons  

PubMed Central

Background: Cervical disc arthroplasty has emerged as a promising potential alternative to anterior cervical discectomy and fusion (ACDF) in appropriately selected patients. Despite a history of excellent outcomes after ACDF, the question as to whether a fusion leads to adjacent segment degeneration remains unanswered. Numerous US investigational device exemption trials comparing cervical arthroplasty to fusion have been conducted to answer this question. Methods: This study reviews the current research regarding cervical athroplasty, and emphasizes both the pros and cons of arthroplasty as compared with ACDF. Results: Early clinical outcomes show that cervical arthroplasty is as effective as the standard ACDF. However, this new technology is also associated with an expanding list of novel complications. Conclusion: Although there is no definitive evidence that cervical disc replacement reduces the incidence of adjacent segment degeneration, it does show other advantages; for example, faster return to work, and reduced need for postoperative bracing. PMID:22905327

Moatz, Bradley; Tortolani, P. Justin

2012-01-01

47

Perioperative plasma erythropoietin levels in hip arthroplasty  

Microsoft Academic Search

Summary To examine the influence of intra- and post-operative blood loss and operative trauma on erythropoietin (EPO) production we studied patients undergoing endoprothetic surgery of the hip. Immunoreactive plasma EPO was determined in ten patients (seven male, three female, aged 39–68 years), undergoing surgery for hip arthroplasty (n=8) or revision hip arthroplasty (n=2). EPO levels had already been determined during

A. Lorentz; K.-U. Eckardt; P. M. Osswald; C. Kruse

1994-01-01

48

Mini-incision for total hip arthroplasty  

Microsoft Academic Search

A group of 42 primary total hip arthroplasties performed through an abridged surgical incision (group 1) was prospectively compared to a cohort of 42 primary total hip arthroplasties performed through a standard surgical incision (group 2). The length of the incision was 8.8 ± 1.5 cm for group 1 and 23.0 ± 2.1 cm for group 2. The groups were

John M Wright; Heber C Crockett; Sam Delgado; Stephen Lyman; Mike Madsen; Thomas P Sculco

2004-01-01

49

Introduction of total knee arthroplasty in Lithuania  

PubMed Central

Background and purpose We have previously reported that the first 10 years of hip arthroplasty in Lithuania resulted in a higher cumulative revision rate than that observed in Sweden. We thus compared the corresponding results after introduaction of total knee replacement in Lithuania. Methods The 10-year revision rate for the first 595 primary ScanKnee arthroplasties inserted in Klaipeda, Lithuania, was compared to that for the first 1,280 ScanKnee primary arthroplasties inserted in Sweden. As in the hip replacement study, only patients with osteoarthritis (OA) were included. Primary knee arthroplasties without patellar resurfacing were included, and the endpoint was revision for any reason other than addition of a patellar component. Results We found that the cumulative revision rate was not statistically significantly different between the groups. The revision pattern was different, however, and we observed 24 isolated patellar component additions in Sweden, but none in Klaipeda. Interpretation Contrary to the results of our previous hip arthroplasty study, the cumulative revision rate after total knee arthroplasty was similar in the two groups. This suggests that compared to hip arthroplasty, the outcome of total knee arthroplasty was less dependent on surgical experience. The large difference regarding isolated patellar component additions may be explained by long-term accumulation of severe OA cases in Lithuania. To patients subject to a newly introduced surgical treatment offering great improvement in quality of life, patellofemoral pain may be a minor problem. Furthermore, patellar problems may not have seemed particularly relevant for the surgeons, considering the disability of other patients waiting to be treated. PMID:19297790

Stucinskas, Justinas; Robertsson, Otto; Wingstrand, Hans

2009-01-01

50

Joint Line Reconstruction in Navigated Total Knee Arthroplasty Revision  

ClinicalTrials.gov

Revision Total Knee Arthroplasty Because of; Loosening; Instability; Impingement; or Other Reasons Accepted as Indications for TKA Exchange.; The Focus is to Determine the Precision of Joint Line Restoration in Navigated vs. Conventional Revision Total Knee Arthroplasty

2012-05-16

51

Coronal Plane Stability Before and After Total Knee Arthroplasty  

E-print Network

Coronal Plane Stability Before and After Total Knee Arthroplasty Robert A. Siston, PhD*,, ; Stuart of total knee arthroplasty depends in part on proper soft tissue management to achieve a stable joint. It is unknown to what degree total knee arthroplasty changes joint stability. We used a surgical navigation

Delp, Scott

52

Solid fusion after lumbosacral arthroplasty  

PubMed Central

A 55-year-old female was diagnosed with L5-S1 degenerative disc disease (DDD). Initial scores by the visual analogue scale (VAS) were 5 (back) and 9 (leg) and the Oswestry disability index (ODI) was 32. Arthroplasty was performed. Clinical and radiographic monitoring took place thereafter at one month, three months, six months and annually. At one month, VAS scores were 2 (back) and 3 (leg), ODI was 12 and ROM was 2.1° by radiographs. At two years, VAS scores were 1 (back) and 2 (leg), ODI was 6 and ROM was approaching 0. Five years after surgery, the entire operated segment (L5-S1) was solidly fused. A malpositioned disc implant may impair normal spinal movement, culminating in heterotopic ossification or complete fusion of the operated segment. PMID:23878786

Jang, Sang-Hoon; Lee, Ho-Yeon; Cho, Ji-Young; Lee, Sang-Ho

2013-01-01

53

Solid fusion after lumbosacral arthroplasty.  

PubMed

A 55-year-old female was diagnosed with L5-S1 degenerative disc disease (DDD). Initial scores by the visual analogue scale (VAS) were 5 (back) and 9 (leg) and the Oswestry disability index (ODI) was 32. Arthroplasty was performed. Clinical and radiographic monitoring took place thereafter at one month, three months, six months and annually. At one month, VAS scores were 2 (back) and 3 (leg), ODI was 12 and ROM was 2.1° by radiographs. At two years, VAS scores were 1 (back) and 2 (leg), ODI was 6 and ROM was approaching 0. Five years after surgery, the entire operated segment (L5-S1) was solidly fused. A malpositioned disc implant may impair normal spinal movement, culminating in heterotopic ossification or complete fusion of the operated segment. PMID:23878786

Jang, Sang-Hoon; Lee, Ho-Yeon; Cho, Ji-Young; Lee, Sang-Ho

2013-07-18

54

Total shoulder arthroplasty in dislocation arthropathy  

PubMed Central

Follow-up examinations of 45 patients who received shoulder arthroplasty for osteoarthritis following shoulder instability were conducted after 44 months. The goal of this study was to describe the clinical findings associated with advanced glenohumeral arthritis due to shoulder instability and instability repairs and to present the clinical results and complications of treating this with shoulder arthroplasty. The weighted average Constant score increased significantly from 49.4 to 81.3 points. There was no significant difference in the type of arthroplasty with 35 cases of total shoulder replacements and ten cases of hemiarthoplasty. The rate of complications was 40% (18/45 patients) with 20% (9/45 patients) requiring an operative revision. Patients with arthritis after instability repair showed great improvement in all qualities of the Constant score. Nonetheless, further analyses are required to determine why such a relatively young group of patients showed high complication rates. PMID:20041242

Magosch, Petra; Mauermann, Eckhard; Lichtenberg, Sven; Habermeyer, Peter

2009-01-01

55

Squeaking hip arthroplasties: a tribological phenomenon.  

PubMed

The clinical incidence of squeaking has been reported with increasing frequency, with ceramic-on-ceramic bearings seemingly most affected. This study investigated potential causes of squeaking in hard-on-hard hip bearings through 2 sets of experimental conditions. Bearing clearance appeared to affect the incidence of squeaking in metal-on-metal surface arthroplasties. The addition of third-body particles to the interface for total hip arthroplasties also affected the incidence of squeaking. In both studies, the incidence of squeaking correlated well with elevated friction. The findings of this study suggest that a likely cause of squeaking in the hip arthroplasty is adverse tribological conditions caused by suboptimal lubrication. There are numerous factors that may cause the suboptimal lubrication, and therefore, it is unlikely that an individual cause for squeaking will be identified. PMID:22480525

Brockett, Claire L; Williams, Sophie; Jin, Zhongmin; Isaac, Graham H; Fisher, John

2013-01-01

56

[Knee arthroplasty in patients with posttraumatic arthritis].  

PubMed

Arthroplasty in patients with posttraumatic arthritis can be challenging due to joint instability, malalignment, osseous defects, non-union, contracture, scarring, low-grade infections and pathologies of the patellofemoral joint. Detailed preoperative planning is recommended concerning incisions, soft tissue management, osseous reconstruction, hardware removal, potential infections and type of prosthesis (e.g. type of constraint, stems and augments). Severe difficulties can occur with exposure of the knee with respect to the extensor mechanism so that quadriceps snip or osteotomy of the tibial tuberosity may be necessary. Postoperative functional results are inferior to arthroplasty for atraumatic gonarthritis. Patients are at increased risk for intraoperative and postoperative complications (e.g. infections, instability, loosening and patellofemoral problems). Reconstructive alternatives (e.g. osteotomy, ligament reconstruction and cartilage repair) should always be considered especially in younger patients; however, most patients show a significant improvement in function and relief of pain after arthroplasty for posttraumatic gonarthritis. PMID:23604339

Hankemeier, S

2013-05-01

57

The clinical outcome of patellofemoral arthroplasty.  

PubMed

Patellofemoral arthroplasty has a long record of use in the treatment of isolated patellofemoral arthritis, with outcomes influenced by patient selection, surgical technique, and trochlear implant design. The trochlear components have evolved from inlay-style to onlay-style designs, which have reduced the incidence of patellar instability. Minimizing the risk of patellar instability with onlay-design patellofemoral arthroplasties has enhanced mid-term and long-term results and leaves progressive tibiofemoral arthritis as the primary failure mechanism beyond 10 to 15 years. PMID:23827831

Lonner, Jess H; Bloomfield, Michael R

2013-07-01

58

Dissociation of Intestinal and Hepatic Activities of FXR and LXR? Supports Metabolic Effects of Terminal Ileum Interposition in Rodents  

PubMed Central

The farnesoid X receptor (FXR) and the liver x receptors (LXRs) are bile acid–activated receptors that are highly expressed in the enterohepatic tissues. The mechanisms that support the beneficial effects of bariatric surgery are only partially defined. We have investigated the effects of ileal interposition (IT), a surgical relocation of the distal ileum into the proximal jejunum, on FXR and LXRs in rats. Seven months after surgery, blood concentrations of total bile acids, taurocholic acid, an FXR ligand, and taurohyocholic acid, an LXR? ligand, were significantly increased by IT (P < 0.05). In contrast, liver and intestinal concentrations of conjugated and nonconjugated bile acids were decreased (P < 0.05). These changes were associated with a robust induction of FXR and FXR-regulated genes in the intestine, including Fgf15, a negative regulator of bile acid synthesis. IT repressed the liver expression of glucose-6-phosphatase (G6PC) and phosphoenolpyruvate carboxykinase (Pepck), two gluconeogenetic genes, along with the expression of LXR? and its target genes sterol regulatory element-binding protein (Srebp) 1c and fatty acid synthase (Fas) in the liver. Treating IT rats with chenodeoxycholic acid ameliorated insulin signaling in the liver. Whether confirmed in human settings, these results support the association of pharmacological therapies with bariatric surgeries to exploit the selective activation of intestinal nuclear receptors. PMID:23835330

Mencarelli, Andrea; Renga, Barbara; D'Amore, Claudio; Santorelli, Chiara; Graziosi, Luigina; Bruno, Angela; Monti, Maria Chiara; Distrutti, Eleonora; Cipriani, Sabrina; Donini, Annibale; Fiorucci, Stefano

2013-01-01

59

Dissociation of intestinal and hepatic activities of FXR and LXR? supports metabolic effects of terminal ileum interposition in rodents.  

PubMed

The farnesoid X receptor (FXR) and the liver x receptors (LXRs) are bile acid-activated receptors that are highly expressed in the enterohepatic tissues. The mechanisms that support the beneficial effects of bariatric surgery are only partially defined. We have investigated the effects of ileal interposition (IT), a surgical relocation of the distal ileum into the proximal jejunum, on FXR and LXRs in rats. Seven months after surgery, blood concentrations of total bile acids, taurocholic acid, an FXR ligand, and taurohyocholic acid, an LXR? ligand, were significantly increased by IT (P < 0.05). In contrast, liver and intestinal concentrations of conjugated and nonconjugated bile acids were decreased (P < 0.05). These changes were associated with a robust induction of FXR and FXR-regulated genes in the intestine, including Fgf15, a negative regulator of bile acid synthesis. IT repressed the liver expression of glucose-6-phosphatase (G6PC) and phosphoenolpyruvate carboxykinase (Pepck), two gluconeogenetic genes, along with the expression of LXR? and its target genes sterol regulatory element-binding protein (Srebp) 1c and fatty acid synthase (Fas) in the liver. Treating IT rats with chenodeoxycholic acid ameliorated insulin signaling in the liver. Whether confirmed in human settings, these results support the association of pharmacological therapies with bariatric surgeries to exploit the selective activation of intestinal nuclear receptors. PMID:23835330

Mencarelli, Andrea; Renga, Barbara; D'Amore, Claudio; Santorelli, Chiara; Graziosi, Luigina; Bruno, Angela; Monti, Maria Chiara; Distrutti, Eleonora; Cipriani, Sabrina; Donini, Annibale; Fiorucci, Stefano

2013-10-01

60

Accuracy of soft tissue balancing in TKA: comparison between navigation-assisted gap balancing and conventional measured resection  

Microsoft Academic Search

Equalized rectangular extension and flexion gaps are considered desirable to ensure proper kinematics in total knee arthroplasty\\u000a (TKA). We compared soft tissue balancing in TKAs performed using navigation-assisted gap-balancing (60 knees) and conventional\\u000a measured resection (56 knees). The outlier of soft tissue balancing was defined as a gap difference >3 mm between the medial\\u000a and lateral sides in 90° flexion and

Dae-Hee Lee; Jong-Hoon Park; Dong-Ik Song; Debabrata Padhy; Woong-Kyo Jeong; Seung-Beom Han

2010-01-01

61

Gap Winds  

NSDL National Science Digital Library

This module provides a basic understanding of why gap winds occur, their typical structures, and how gap wind strength and extent are controlled by larger-scale, or synoptic, conditions. You will learn about a number of important gap flows in coastal regions around the world, with special attention given to comprehensively documented gap wind cases in the Strait of Juan de Fuca and the Columbia River Gorge. Basic techniques for evaluating and predicting gap flows are presented. The module reviews the capabilities and limitations of the current generation of mesoscale models in producing realistic gap winds. By the end of this module, you should have sufficient background to diagnose and forecast gap flows around the world, and to use this knowledge to understand their implications for operational decisions. Other features in this module include a concise summary for quick reference and a final exam to test your knowledge. Like other modules in the Mesoscale Meteorology Primer, this module comes with audio narration, rich graphics, and a companion print version.

Comet

2003-03-20

62

Automated Planning of Computer Assisted Mosaic Arthroplasty  

E-print Network

Automated Planning of Computer Assisted Mosaic Arthroplasty Jiro Inoue1,3 , Manuela Kunz1,3 , Mark Hurtig4 , Stephen Waldman2,3 , James Stewart1,3 1 School of Computing, 2 Department of Mechanical Veterinary College, University of Guelph Abstract. We describe and evaluate a computer algorithm that auto

Stewart, James

63

Automated Planning of Computer Assisted Mosaic Arthroplasty  

E-print Network

to avoid degeneration at the bone/cartilage interface; ­ the plug harvest sites must be planned soAutomated Planning of Computer Assisted Mosaic Arthroplasty Abstract. We describe and evaluate a computer algorithm that auto- matically develops a surgical plan for computer assisted mosaic arthro

Waldman, Stephen D.

64

Bearing couples in total hip arthroplasty.  

PubMed

Total hip arthroplasty is a well-established treatment for arthritis of the hip. The choice of bearing couple used for articulation should be tailored to the patient. This article reviews the history of different bearing surfaces, and outlines the advantages and disadvantages that may influence their use. PMID:20852486

Tailor, Hiteshkumar; Patel, Shelain; Patel, Rahul V; Haddad, Fares S

2010-08-01

65

(i) Alternative bearing surfaces for hip arthroplasty  

Microsoft Academic Search

Over 50,000 hip replacements are performed per year in NHS hospitals, independent sector hospitals and treatment centres. Since the concept of low frictional arthroplasty was first introduced, aspirations and lifestyles have changed dramatically. Expectations of outcomes have risen, yet more patients with severe co-morbidity of affluent lifestyle (obesity, diabetes and hypertensive cardiac disease) undergo surgery. Implant survival will be aided

Timothy Guy McWilliams; James R. Parker

2009-01-01

66

Early dislocation after total hip arthroplasty  

Microsoft Academic Search

Background: The average incidence of dislocation after total hip arthroplasty is approximately 3%. However, the choice of surgical approa- ch can affect the rate of postoperative dislocation. A 5.8% dislocation rate has previously been reported when a poste- rolateral approach was used compaired with z.3% when an anterolateral approa- ch was used. The aim of this study was therefore to

N. Levi; P. Gebuhr

2001-01-01

67

Girdlestone resection arthroplasty following failed surgical procedures  

Microsoft Academic Search

We retrospectively reviewed 43 patients who had undergone Girdlestone resection arthroplasty of the hip after failed total hip replacement or failed operations for hip trauma between 1990 and 2002. The indications were peri-prosthetic infection, aseptic loosening, recurrent dislocation and failed internal fixation for femoral neck fractures. Twenty-five patients died with an overall mortality of 58%. Out of 18 survivors, four

H. Sharma; J. De Leeuw; D. I. Rowley

2005-01-01

68

Total knee arthroplasty with the PFC system  

Microsoft Academic Search

consecutive series of 235 total knee arthroplasties using the PFC system was followed prospectively for at least ten years in 186 patients. The operation was for osteoarthritis in 150 knees, for rheumatoid arthritis in 83, and for Paget's disease and femoral osteonecrosis in one knee each. At the latest review 56 patients had died, fi ve were too ill to

Pascal A. Schai; Thomas S. Thornhill; Richard D. Scott

1998-01-01

69

Knee arthroplasty in Denmark, Norway and Sweden  

PubMed Central

Background and purpose The number of national arthroplasty registries is increasing. However, the methods of registration, classification, and analysis often differ. Methods We combined data from 3 Nordic knee arthroplasty registers, comparing demographics, methods, and overall results. Primary arthroplasties during the period 1997–2007 were included. Each register produced a dataset of predefined variables, after which the data were combined and descriptive and survival statistics produced. Results The incidence of knee arthroplasty increased in all 3 countries, but most in Denmark. Norway had the lowest number of procedures per hospital—less than half that of Sweden and Denmark. The preference for implant brands varied and only 3 total brands and 1 unicompartmental brand were common in all 3 countries. Use of patellar button for total knee arthroplasty was popular in Denmark (76%) but not in Norway (11%) or Sweden (14%). Uncemented or hybrid fixation of components was also more frequent in Denmark (22%) than in Norway (14%) and Sweden (2%). After total knee arthroplasty for osteoarthritis, the cumulative revision rate (CRR) was lowest in Sweden, with Denmark and Norway having a relative risk (RR) of 1.4 (95% CI: 1.3–1.6) and 1.6 (CI: 1.4–1.7) times higher. The result was similar when only including brands used in more than 200 cases in all 3 countries (AGC, Duracon, and NexGen). After unicompartmental arthroplasty for osteoarthritis, the CRR for all models was also lowest in Sweden, with Denmark and Norway having RRs of 1.7 (CI: 1.4–2.0) and 1.5 (CI: 1.3–1.8), respectively. When only the Oxford implant was analyzed, however, the CRRs were similar and the RRs were 1.2 (CI: 0.9–1.7) and 1.3 (CI: 1.0–1.7). Interpretation We found considerable differences between the 3 countries, with Sweden having a lower revision rate than Denmark and Norway. Further classification and standardization work is needed to permit more elaborate studies. PMID:20180723

Bizjajeva, Svetlana; Fenstad, Anne Marie; Furnes, Ove; Lidgren, Lars; Mehnert, Frank; Odgaard, Anders; Pedersen, Alma Becic; Havelin, Leif Ivar

2010-01-01

70

Qualifying CT for wrist arthroplasty: extending techniques for total hip arthroplasty to total wrist arthroplasty  

NASA Astrophysics Data System (ADS)

The purpose of this study was to extend previous work to detect migration of total wrist arthroplasty non-invasively, and with greater accuracy. Two human cadaverous arms, each with a cemented total wrist implant, were used in this study. In one of the arms, 1 mm tantalum balls were implanted, six in the carpal bones and five in the radius. Five CT scans of each arm were acquired, changing the position of the arm each time to mimic different positions patients might take on repeated examinations. Registration of CT volume data sets was performed using an extensively validated, 3D semi-automatic volume fusion tool in which co-homologous point pairs (landmarks) are chosen on each volume to be registered. Three sets of ten cases each were obtained by placing landmarks on 1) bone only (using only arm one), 2) tantalum implants only, and 3) bone and tantalum implants (both using only arm two). The accuracy of the match was assessed visually in 2D and 3D, and numerically by calculating the distance difference between the actual position of the transformed landmarks and their ideal position (i.e., the reference landmark positions). All cases were matched visually within one width of cortical bone and numerically within one half CT voxel (0.32 mm, p = 0.05). This method matched only the bone/arm and not the prosthetic component per se, thus making it possible to detect prosthetic movement and wear. This method was clinically used for one patient with pain. Loosening of the carpal prosthetic component was accurately detected and this was confirmed at surgery.

Alcala, Yvonne; Olivecrona, Henrik; Olivecrona, Lotta; Noz, Marilyn E.; Maguire, Gerald Q., Jr.; Zeleznik, Michael P.; Sollerman, Christer

2005-04-01

71

Cost Analysis in Shoulder Arthroplasty Surgery  

PubMed Central

Cost in shoulder surgery has taken on a new focus with passage of the Patient Protection and Affordable Care Act. As part of this law, there is a provision for Accountable Care Organizations (ACOs) and the bundled payment initiative. In this model, one entity would receive a single payment for an episode of care and distribute funds to all other parties involved. Given its reproducible nature, shoulder arthroplasty is ideally situated to become a model for an episode of care. Currently, there is little research into cost in shoulder arthroplasty surgery. The current analyses do not provide surgeons with a method for determining the cost and outcomes of their interventions, which is necessary to the success of bundled payment. Surgeons are ideally positioned to become leaders in ACOs, but in order for them to do so a methodology must be developed where accurate costs and outcomes can be determined for the episode of care. PMID:23243515

Teusink, Matthew J.; Virani, Nazeem A.; Polikandriotis, John A.; Frankle, Mark A.

2012-01-01

72

Revision of humeral components in shoulder arthroplasty.  

PubMed

Revision of a shoulder arthroplasty often requires removal of a well fixed humeral component. Revision of this component can be quite easy in the case of a non-infected platform stem or be very difficult when removal of a well cemented or on-growth stem with distal texturing is required. The purpose of this paper is to provide a series of techniques designed for revision of the humeral component in shoulder arthroplasty. Revision of the stem can be easy with a non-infected platform stem only requiring exchange of the epiphyseal component. Some stems, usually uncemented, can readily be removed from a proximal only approach. Stems with excellent cement mantles may require a longitudinal only split in the humerus done with minimal stripping of the brachialis. If complete cement removal is needed for infection or there is distal stem on growth, then a vascularized door technique is indicated. These techniques are explained in detail in this manuscript. PMID:24328586

Wright, Thomas W

2013-01-01

73

Reducing and recycling in joint arthroplasty.  

PubMed

Reducing the need for costly contaminated waste processing after total hip arthroplasties (THAs) and total knee arthroplasties (TKAs) could decrease hospital overhead and the environmental impact. From March through April 2011, we prospectively identified 20 consecutive patients undergoing primary THA or TKA by 1 surgeon in 1 operating room at our institution. For each case, waste (excluding liquids) was collected and sorted as it was produced. The 10 THAs and 10 TKAs produced an average of 30.0 lb (range, 27.1-32.5) and 33.2 lb (range, 30.9-35.2) of waste per procedure, respectively, of which 6.8 lb (range, 6.0-7.8; 22.8%) and 7.3 lb (range, 5.4-8.7; 22.0%), respectively, were potentially recyclable paper or plastic. Waste management programs should focus on recycling clean operating room waste. PMID:22704228

Lee, Rushyuan J; Mears, Simon C

2012-12-01

74

Total knee arthroplasty in patients with poliomyelitis.  

PubMed

Between 1991 and 2001, 17 primary total knee arthroplasties were performed in 15 patients with limbs affected by poliomyelitis. Eight patients had a constrained condylar knee design, 8 a posterior stabilized design, and 1 a hinged design. Mean follow-up was 41.5 months. The mean Knee Society knee score improved from 45 preoperatively to 87 postoperative. Knee stability was obtained in all patients, including 4 patients with less than antigravity quadriceps strength. Radiologic evaluation showed satisfactory alignment with no signs of loosening. Complications included 1 case of deep venous thrombosis and 2 knees that required a manipulation for stiffness. Pain relief, functional improvement, and knee stability can be achieved after constrained total knee arthroplasty in patients with poliomyelitis despite impaired quadriceps strength, and osseous and soft tissue abnormalities. PMID:17562411

Jordan, Louis; Kligman, Mordechai; Sculco, Thomas P

2007-06-01

75

Wrist Arthrodesis as a Salvage Procedure for Failed Implant Arthroplasty  

Microsoft Academic Search

Salvage of failed total wrist arthroplasty by arthrodesis may be difficult because of bone loss and poor quality of bone and soft tissues. We examined the outcomes of wrist arthrodesis for failed total wrist arthroplasty in a retrospective study of 21 wrists in 17 patients. Clinical data, radiographs, patient-reported outcomes and DASH questionnaires were used. Thirteen women and four men

M. Rizzo; D. B. Ackerman; R. L. Rodrigues; R. D. Beckenbaugh

2011-01-01

76

Total knee arthroplasty after high tibial osteotomy. A systematic review  

Microsoft Academic Search

BACKGROUND: Previous osteotomy may compromise subsequent knee replacement, but no guidelines considering knee arthroplasty after prior osteotomy have been developed. We describe a systematic review of non-randomized studies to analyze the effect of high tibial osteotomy on total knee arthroplasty. METHODS: A computerized search for relevant studies published up to September 2007 was performed in Medline and Embase using a

Tom M van Raaij; Max Reijman; Andrea D Furlan; Jan AN Verhaar

2009-01-01

77

Indications for total hip and total knee arthroplasties  

Microsoft Academic Search

A lack of consensus regarding the indications for total hip arthroplasty (THA) and total knee arthroplasty (TKA) has been cited as one reason for the variations in the rates of THA and TKA across the United States. The purposes of this study were to survey orthopaedists in a specific geographic area (New York City) regarding the candidacy of patients with

Carol A. Mancuso; Chitranjan S. Ranawat; John M. Esdaile; Norman A. Johanson; Mary E. Charlson

1996-01-01

78

Optimized Registration for Computer Assisted Total Knee Arthroplasty  

E-print Network

260 Optimized Registration for Computer Assisted Total Knee Arthroplasty Jon-Michael Tucker, Mc Pennsylvania State University Introduction: Total knee arthroplasty, (TKA), also known as total knee, a cement epoxy is then used to firmly secure the mechanical components that will operate as "new knees

Omiecinski, Curtis

79

Avulsion fracture of the ischium following complex total hip arthroplasty  

Microsoft Academic Search

Total hip arthroplasty in the high riding dislocated hip is a technically difficult undertaking, with major reconstruction required on both the acetabular and femoral sides. With reconstruction at a near-anatomic hip center, reduction of the arthroplasty is difficult because of the long-standing limb shortening. The major block to reduction is tension of the soft tissues, particularly the hamstrings. We report

Paul N. Smith; Graham A. Gie

1998-01-01

80

Total knee arthroplasty: looks good, feels bad  

Microsoft Academic Search

Total knee arthroplasty has a high success rate but approximately 4%–5% of patients have fair to poor results and 1% of patients are extremely unhappy. With a complete work-up a diagnosis can usually be made to explain the patient’s symptoms and lead to an appropriate solution. In that small percentage of cases (1%) with unexplained pain or dysfunction, surgical intervention

James A D’Antonio

2003-01-01

81

Lateral unicompartmental knee arthroplasty: a review  

Microsoft Academic Search

Lateral unicondylar knee arthroplasty (UKA) has been utilized as a treatment for isolated lateral tibiofemoral osteoarthritis\\u000a (OA) since the first description of UKA in the 1970s. To date, there remains some controversy on UKA procedures. As indications\\u000a for lateral UKA are usually rare, surgeon experience seems to be the key factor for a successful intervention. Better understanding\\u000a of biomechanics of

Thomas J. HeyseCarsten; Carsten O. Tibesku

2010-01-01

82

Intraosseous lymphocytic infiltrates after hip resurfacing arthroplasty  

Microsoft Academic Search

To identify a possible role of lymphocytic infiltrates in failure mechanism of the metal-on-metal hip resurfacing arthroplasty,\\u000a the extent of lymphocytic infiltration was compared with reasons for prosthesis failure in a series of retrieval specimens.\\u000a One hundred eighty-one femoral head and neck remnants were subjected to thorough analysis of histological findings and clinical\\u000a data. Lymphocytic infiltrates were considered weak to

Jozef Zustin; Michael Amling; Matthias Krause; Stefan Breer; Michael Hahn; Michael M. Morlock; Wolfgang Rüther; Guido Sauter

2009-01-01

83

Press-fit condylar total knee arthroplasty  

Microsoft Academic Search

Between November 1984 and December 1987, 378 consecutive Press-Fit Condylar (PFC, Johnson & Johnson Professional, Raynham, MA) total knee arthroplasties were performed in 290 patients. The average age at surgery was 67 years (range, 22–91 years). The average follow-up period was 6.5 years (range, 5–9 years). Scoring was carried out according to the Knee Society scoring system. The average preoperative

Scott David Martin; Jacquelyn L. McManus; Richard D. Scott; Thomas S. Thornhill

1997-01-01

84

Resection arthroplasty for failed patellar components  

Microsoft Academic Search

A total of 1,401 primary total knee arthroplasties (TKA) were reviewed; 44 (3.2%) had at least the patellar component revised.\\u000a Nine of these knees (eight patients) had insufficient bone stock to allow reimplantation of another patellar component. Clinical\\u000a data on the nine knees were obtained with recent follow-up evaluation, review of their medical records and radiographs. Evaluation\\u000a included Hospital for

Carlos J. Lavernia; Jose C. Alcerro; Michael K. Drakeford; Audrey K. Tsao; Kenneth A. Krackow; David S. Hungerford

2009-01-01

85

Bilateral piriformis syndrome after total hip arthroplasty  

Microsoft Academic Search

We present the case of a 39-year-old man with bilateral piriformis syndrome 4 and 6 years after two cementless total hip\\u000a arthroplasties, respectively. During surgical exploration, each sciatic nerve was found to be entrapped by a tense piriformis\\u000a muscle and hypertrophic posterior hip capsule. The sciatic-type pain was relieved after sectioning each piriformis muscle\\u000a with external neurolysis. This is the

Y. Uchio; U. Nishikawa; M. Ochi; N. Shu; K. Takata

1998-01-01

86

Preoperative planning and postoperative imaging in shoulder arthroplasty.  

PubMed

The number of shoulder arthroplasties performed in the United States has more than doubled in the last decade. Additionally, there has been a trend toward use of reverse total shoulder arthroplasty and minimally invasive surgical techniques, such as resurfacing humeral head arthroplasty. Thus radiologists will more frequently encounter imaging of shoulder arthroplasty and these new designs. Successful postoperative radiologic evaluation of shoulder reconstructions requires an understanding of their fundamental hardware design, physiologic objective, preoperative imaging assessment, normal postoperative radiologic appearance, and findings and types of complication. This article discusses the designs of prostheses used around the shoulder joint, delineates indications and alternatives for each of the different types of hardware, reviews radiographic and cross-sectional preoperative imaging of shoulder arthroplasty, illustrates normal postoperative imaging findings and measurements, and provides examples of hardware complications. PMID:25184399

Petscavage-Thomas, Jonelle

2014-09-01

87

Ceramic-on-ceramic total hip arthroplasty early dislocation rate.  

PubMed

Wear debris from metal-on-polyethylene articulation in conventional total hip arthroplasty can limit the implant's longevity. Modern ceramic material with high wear resistance and low fracture risk has the potential to extend the lifetime of total hip arthroplasty, which makes the procedure potentially more suitable for young, active patients. Concerns with brittle ceramic material include fracture risk, the "squeak" phenomenon, and potentially a higher dislocation rate secondary to limited neck lengths and liner options. We therefore determined the early dislocation rate in modern ceramic-on-ceramic total hip arthroplasty. In 1635 total hip arthroplasties performed over the 9-year period (1996-2005), we observed three anterior and 15 posterior dislocations (1.1%). All were treated successfully, one with a revision and 17 with closed reduction under general anesthesia. Ceramic-on-ceramic total hip arthroplasty can be a good alternative bearing surface with a low dislocation rate. PMID:17667324

Colwell, Clifford W; Hozack, William J; Mesko, J Wesley; D'Antonio, James A; Bierbaum, Benjamin E; Capello, William N; Jaffe, William L; Mai, Kenny T

2007-12-01

88

Does arthroplasty type influence knee joint proprioception? A longitudinal prospective study comparing total and unicompartmental arthroplasty  

Microsoft Academic Search

Proprioception was assessed after knee replacement to compare total (TKA) to unicompartmental (UKA) knee arthroplasty. Thirty-four patients were recruited; seventeen patients underwent TKA and seventeen patients underwent UKA. The patient's age was similar in both groups. Two measures of proprioception, joint position sense (JPS) and postural sway (PS) were measured. Function was assessed using the Oxford Knee Score (OKS). Measurements

S. M. Isaac; K. L. Barker; I. N. Danial; D. J. Beard; C. A. Dodd; D. W. Murray

2007-01-01

89

Salvage of failed total hip arthroplasty with proximal femoral replacement.  

PubMed

EDUCATIONAL OBJECTIVES As a result of reading this article, physicians should be able to: 1. Identify the available types of reconstruction for failed total hip arthroplasty. 2. Summarize the preoperative workup of patients with failed total hip arthroplasty and massive proximal femoral bone loss. 3. Assess the surgical technique of proximal femoral replacement for failed total hip arthroplasty. 4. Recognize treatment complications, patient outcomes, and survival of proximal femoral megaprostheses for revision of failed total hip arthroplasty. Despite recent advances in device manufacturing and surgical techniques, the management of proximal femoral bone loss in revision total hip arthroplasty remains challenging. Currently, failed total hip arthroplasty in elderly and less active patients, nonunion of the proximal femur with multiple failed attempts at osteosynthesis, resection arthroplasty, and massive proximal femoral bone loss can be salvaged with proximal femoral replacement using a megaprosthesis. The procedure is technically demanding and requires careful preoperative planning. Instability and aseptic loosening are the major complications, especially in younger and more active patients. The new generation of modular proximal femoral replacement megaprostheses and the increased experience obtained with these surgeries have reduced complication rates and improved outcomes. [Orthopedics. 2014; 37(10):691-698.]. PMID:25275970

Savvidou, Olga D; Mavrogenis, Andreas F; Sakellariou, Vasilios; Christogiannis, Ioannis; Vottis, Christos; Christodoulou, Michael; Vlasis, Konstantinos; Papagelopoulos, Panayiotis J

2014-09-01

90

Unusual cases of pigmented villonodular synovitis after arthroplasty  

PubMed Central

Pigmented Villonodular Synovitis (PVNS) is a relatively rare, benign proliferation lesion of the synovium of large joints. The etiology is varied and unclear. We had report a 79-year-old woman had PVNS after 14 years right hip arthroplasty with metal prosthesis. Here we report another 4 patients had PVNS after arthroplasty. The second one had PVNS in the 2th year after hip arthroplasty with bone cement prosthesis. The specimen was brown and like usual PVNS in tissue. The third case had PVNS in the 8th after arthroplasty with human bone prosthesis because of the recurrence of PVNS. The proliferated synovium became black from brown. There was brown and many groups black pigment in the tissue. The fourth one had PVNS in the 4th year after knee arthroplasty with polyethylene prosthesis. The specimen was yellow. There was no pigment in the tissue but multinucleated giant cells with unstained foreign body. The fifth patient had PVNS in the 10th month after the left hip arthroplasty with metal prosthesis. The macroscopy was yellow. There were hemosiderin particles in the tissue but black metal particles. This indicates that arthroplasty with prosthesis could cause some new disease or PVNS had new etiology with different pathological show. PMID:24955198

Ma, Xiao-Mei; Xia, Chun-Yan; Fu, Pei-Liang; Liu, Hui-Min; Yu, Hong-Yu; He, Jin

2014-01-01

91

High-flexion total knee arthroplasty: a systematic review  

PubMed Central

This study is a systematic literature review of outcomes following total knee arthroplasty with implants specifically designed to enable increased knee flexion. English language comparative studies without date restriction were identified through a computerised literature search and bibliography review. Nine studies met the inclusion criteria representing a total of 399 high-flexion knee arthroplasties in 370 patients. Five studies reported greater flexion or range of motion; however, the methodological rigour was questionable with inadequate blinding, flawed participant selection, short follow-up periods and functional outcomes which lacked sensitivity. There was insufficient evidence of improved range of motion or functional performance after high-flexion knee arthroplasty. PMID:19352655

Journeaux, Simon; Russell, Trevor

2009-01-01

92

Measured flexion following total knee arthroplasty.  

PubMed

Postoperative flexion is an important factor in the outcome of total knee arthroplasty. Although normal activities of daily living require a minimum of 105° to 110° of flexion, patients from non-Western cultures often engage in activities such as kneeling and squatting that require higher flexion. The desire to achieve greater flexion serves as the driving force for prosthetic modifications, including high-flexion designs. Techniques used to measure knee flexion and knee position during measurement are not often described or are different depending on the examiner. The purpose of this study was to compare active (self) and passive (assisted) flexion after successful total knee arthroplasty for 5 prostheses (2 standard and 3 high-flexion) using clinical (goniometer) and radiographic (true lateral radiograph) measurement techniques by different independent examiners.At a mean follow-up of 2.7 years (range, 1-5.6 years), a total of 108 patients (144 total knee arthroplasties) had completed the study. Mean postoperative active flexion was 111° clinically and 109° radiographically for the standard designs and 114° clinically and 117° radiographically for the high-flexion designs. Adding passive flexion increased flexion to 115° clinically and 117° radiographically for the standard designs and 119° clinically and 124° radiographically for the high-flexion designs. Flexion differences between the 2 measurement techniques (active vs passive and clinically vs radiographically) were statistically significant (P<.05). These findings demonstrate the importance of describing how flexion is measured in studies and understanding how the method of measurement can affect the findings. PMID:23027482

Mai, Kenny T; Verioti, Christopher A; Hardwick, Mary E; Ezzet, Kace A; Copp, Steven N; Colwell, Clifford W

2012-10-01

93

Vaginal mass following uncemented total hip arthroplasty  

PubMed Central

A 53-year-old woman developed a vaginal mass following an uncemented total hip arthroplasty. The mass was in direct communication with the hip through an acetabular medial wall defect after loosening of the acetabular component. The mass formation was caused simultaneously by changes secondary to polyethylene wear, a tiny delamination of the porous titanium mesh coating and a broken antirotational tab on the acetabular cup, all of which may have served as sources of metal particles. A careful evaluation of the patient's history, symptoms, X-ray findings and computed tomography scans should always be performed to ensure accurate diagnosis.

Shin, Young-Soo; Jung, Tae-Wan; Han, Seung-Beom

2014-01-01

94

Vaginal mass following uncemented total hip arthroplasty.  

PubMed

A 53-year-old woman developed a vaginal mass following an uncemented total hip arthroplasty. The mass was in direct communication with the hip through an acetabular medial wall defect after loosening of the acetabular component. The mass formation was caused simultaneously by changes secondary to polyethylene wear, a tiny delamination of the porous titanium mesh coating and a broken antirotational tab on the acetabular cup, all of which may have served as sources of metal particles. A careful evaluation of the patient's history, symptoms, X-ray findings and computed tomography scans should always be performed to ensure accurate diagnosis. PMID:25404779

Shin, Young-Soo; Jung, Tae-Wan; Han, Seung-Beom

2014-11-01

95

Results of primary total knee arthroplasty in Jehovah's Witness patients.  

PubMed

Total knee arthroplasty can be challenging in Jehovah's Witnesses, as these patients do not accept blood transfusions. We reported our experiences with a special blood management protocol for these patients who underwent total knee arthroplasty. There were 124 self-reported Jehovah's Witnesses who had a mean age of 64 years and who underwent total knee arthroplasties between 1998 and 2009. Mean follow-up was 60 months (range, 24-120 months). Implant survivorship, with revision for aseptic component failure as an end point, was 98%. At the final follow-up, mean Knee Society objective and function score improved to 91 and 81 points, respectively. The authors believe that this blood management protocol was responsible for performing safe and transfusion-free total knee arthroplasties that can ultimately lead to excellent outcomes. PMID:22771089

Harwin, Steven F; Issa, Kimona; Naziri, Qais; Johnson, Aaron J; Mont, Michael A

2013-01-01

96

Activity Levels in Healthy Older Adults: Implications for Joint Arthroplasty  

PubMed Central

This work evaluated activity levels in a group of healthy older adults to establish a target activity level for adults of similar age after total joint arthroplasty (TJA). With the decreasing age of TJA patients, it is essential to have a reference for activity level in younger patients as activity level affects quality of life and implant design. 54 asymptomatic, healthy older adults with no clinical evidence of lower extremity OA participated. The main outcome measure, average daily step count, was measured using an accelerometer-based activity monitor. On average the group took 8813 ± 3611 steps per day, approximately 4000 more steps per day than has been previously reported in patients following total joint arthroplasty. The present work provides a reference for activity after joint arthroplasty which is relevant given the projected number of people under the age of 65 who will undergo joint arthroplasty in the coming years. PMID:23577274

Thorp, Laura E.; Orozco, Diego; Block, Joel A.; Sumner, Dale R.; Wimmer, Markus A.

2012-01-01

97

Hierarchy of Stability Factors in Reverse Shoulder Arthroplasty  

PubMed Central

Reverse shoulder arthroplasty is being used more frequently to treat irreparable rotator cuff tears in the presence of glenohumeral arthritis and instability. To date, however, design features and functions of reverse shoulder arthroplasty, which may be associated with subluxation and dislocation of these implants, have been poorly understood. We asked: (1) what is the hierarchy of importance of joint compressive force, prosthetic socket depth, and glenosphere size in relation to stability, and (2) is this hierarchy defined by underlying and theoretically predictable joint contact characteristics? We examined the intrinsic stability in terms of the force required to dislocate the humerosocket from the glenosphere of eight commercially available reverse shoulder arthroplasty devices. The hierarchy of factors was led by compressive force followed by socket depth; glenosphere size played a much lesser role in stability of the reverse shoulder arthroplasty device. Similar results were predicted by a mathematical model, suggesting the stability was determined primarily by compressive forces generated by muscles. PMID:18264855

Gutierrez, Sergio; Keller, Tony S.; Levy, Jonathan C.; Lee, William E.

2008-01-01

98

Deep infection in total hip arthroplasty  

PubMed Central

Objective To report on a 30-year prospective study of deep infection in 1993 consecutive total hip arthroplasties performed by a single surgeon. Methods The relations of numerous variables to the incidence of deep infection were studied. Results The cumulative infection rate after the index total hip arthroplasties rose from 0.8% at 2 years to 1.4% at 20 years; 9.6% of the index operations required further surgery. When infections attributed to these secondary procedures were included, the infection rate rose from 0.9% at 2 years to 2% at 20 years. Although the usual variables increased the incidence of infection, the significant and most precise predictors of infection were radiologic diagnoses of upper pole grade III and protrusio acetabuli, an elevated erythrocyte sedimentation rate, alcoholism and units of blood transfused. Conclusion From 2–20 years, the incidence of deep infection doubled. Preoperative recognition of the first 4 risk factors permits the use of additional prophylactic measures. Spinal or epidural anesthesia reduced the units of blood transfused (the fifth risk factor) and, hence, the risk of infection. Although most deep infections are seeded while the wound is open, there are many possible postoperative causes. In this study, fewer than one-third of the infections that presented after 2 years were related to hematogenous spread. The efficacy of clean air technology was supported, and it is recommended that all measures that may reduce the incidence of deep infection be employed. PMID:18377751

Hamilton, Henry; Jamieson, John

2008-01-01

99

Why Revision Total Hip Arthroplasty Fails  

PubMed Central

Current outcomes data on revision total hip arthroplasty focuses on specific implants and techniques rather than more general outcomes. We therefore examined a large consecutive series of failed THAs undergoing revision to determine if survivorship and modes of failure differ in comparison to the current data. We retrospectively reviewed the medical records of 1100 revision THAs. The minimum followup was 2 years (mean, 6 years; range, 0–20.4 years). Eighty-seven percent of revision total hips required no further surgery; however, 141 hips (13%) underwent a second revision at a mean of 3.7 years (range, 0.025–15.9 years). Seventy percent (98 hips) had a second revision for a diagnosis different from that of their index revision, while 30% (43 hips) had a second revision for the same diagnosis. The most common reasons for failure were instability (49 of 141 hips, 35%), aseptic loosening (42 of 141 hips, 30%), osteolysis and/or wear (17 of 141 hips, 12%), infection (17 of 141 hips, 12%), miscellaneous (13 of 141 hips, 9%), and periprosthetic fracture (three of 141 hips, 2%). Survivorship for revision total hip arthroplasty using second revision as endpoint was 82% at 10 years. Aseptic loosening and instability accounted for 65% of these failures. Level of Evidence: Level IV, therapeutic (retrospective) study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18975043

Fehring, Thomas K.; Griffin, William L.; Odum, Susan M.; Masonis, John L.

2008-01-01

100

Preoperative laxity in osteoarthritis patients undergoing total knee arthroplasty  

Microsoft Academic Search

A preoperative quantitative evaluation of soft tissues is helpful for planning total knee arthroplasty, in addition to the\\u000a conventional clinical examinations involved in moving the knee manually. We evaluated preoperative coronal laxity with osteoarthritis\\u000a in patients undergoing total knee arthroplasty by applying a force of 150 N with an arthrometer. We examined a consecutive\\u000a series of 120 knees in 102 patients.

Yoshinori Ishii; Hideo Noguchi; Yoshikazu Matsuda; Hiroshi Kiga; Mitsuhiro Takeda; Shin-ichi Toyabe

2009-01-01

101

Utility of polymer cerclage cables in revision shoulder arthroplasty.  

PubMed

Revision shoulder arthroplasty often requires humeral osteotomy for stem extraction or is complicated by periprosthetic fracture. In these situations, various modes of fixation are used, including cerclage wires, cable plates, and allograft strut augmentation. The use of metal wires and cables, however, has been associated with soft tissue irritation, sharps injuries, and accelerated wear of joint arthroplasty bearing surfaces. As an alternative to traditional metal cables, the SuperCable (Kinamed Inc, Camarillo, California) contains braided ultra-high molecular-weight polyethylene fibers surrounding a nylon core. To date, no studies have examined the use of nonmetallic cerclage cables in shoulder arthroplasty.A retrospective review was performed of 11 patients who underwent shoulder arthroplasty for which nonmetallic cerclage cables were used. Clinical and radiographic data were examined regarding patient age, procedure performed, indication for cerclage cabling, time to healing of osteotomy or fracture, and any complications associated with the use of these cerclage cables. Minimum follow-up was 1 year. Ten patients underwent reverse total shoulder arthroplasty, and 1 patient underwent revision unconstrained total shoulder arthroplasty. Mean follow-up was 20.5 months. Ten patients required humeral osteotomy for stem or cement removal. Allograft augmentation was performed in 7 patients. Mean time to healing was 3.2 months. No patients experienced loosening or migration of hardware or allograft, and no complications directly related to the use of nonmetallic cerclage cables were identified. PMID:21469627

Edwards, T Bradley; Stuart, Kyle D; Trappey, George J; O'Connor, Daniel P; Sarin, Vineet K

2011-04-01

102

Minimally invasive Oxford medial unicompartmental knee arthroplasty  

PubMed Central

We present the peak outcome results of the Oxford medial unicompartmental arthroplasty through a minimally invasive ssurgical incision. This prospective study included 78 Oxford medial unicompartmental knee replacements in 68 patients. At the 2 year review the patients achieved a mean Oxford Knee Score of 38.3. This was not significantly different to the 2 year results of the phase 2 Oxford knee carried out using a standard parapatellar approach when patients achieved a mean OKS of 36.0. Four unicompartmental knee replacements required revision for unexplained pain, deep infection, aseptic loosening and bearing dislocation. Minimally invasive joint replacement is attractive to both patients and surgeons, but is technically demanding with complications inherent to limited access. PMID:16896865

Lim, J.; Jones, P. W.; White, S. H.

2006-01-01

103

Revision total hip arthroplasty in Jehovah's Witnesses.  

PubMed

Revision total hip arthroplasty (THA) is associated with greater blood loss than primary THA. Jehovah's Witnesses will not accept transfusions of blood or blood products and are thus at an increased risk for complications due to perioperative anemia. The purpose of this study was to report the clinical outcomes, radiographic outcomes, morbidity, and mortality of Jehovah's Witnesses who were medically optimized and underwent revision THA. Databases from 2 institutions were reviewed to identify 10 patients (11 THAs) who were Jehovah's Witnesses undergoing revision THA with a minimum 24-month follow-up. At most recent follow-up, all patients were doing well clinically, with Harris Hip Scores greater than 80 points. Radiographic evaluation demonstrated well-positioned components and no progressive radioluciencies. No major perioperative medical or surgical complications occurred in patients undergoing THA. Revision THA for aseptic causes results in good clinical outcomes in patients who are preoperatively optimized before undergoing surgery. PMID:22868597

Harwin, Steven F; Pivec, Robert; Johnson, Aaron J; Naziri, Qais; Mont, Michael A

2012-08-01

104

Patellar meniscus in total knee arthroplasty.  

PubMed

Twenty-four clinically successful, autopsy retrieved porous-coated anatomic total knee arthroplasty (TKA) specimens were evaluated to determine the structure and function of the patellar meniscus. Mean implant duration was 76 months (range: 11-135 months). Histological examination showed the patellar meniscus to be composed of dense fibrous tissue with scattered regions of chronic granulomatous response to polyethylene debris. Patellar wear and polyethylene exposed patellar surface area were correlated with implant duration (r = 0.47, P = .03; r = 0.52, P = .06). Postoperative patellar tilt was also associated with patellar component wear (r = 0.64, P = .03). No other clinical measures were significantly associated with patellar wear or exposed surface area. Additional research is needed to determine what role, if any, the patellar meniscus plays in TKA outcomes. PMID:17486906

Lavernia, Carlos J; Sheldon, Daniel A; Hernández, Victor H; D'Apuzzo, Michele R; Lee, David J; Krackow, Kenneth A; Hungerford, David S

2007-04-01

105

Experiences with computer navigated total knee arthroplasty  

PubMed Central

The successful outcome of total knee arthroplasty (TKA) is very much dependent on precise positioning of the components. Inaccuracy may result in complaints as well as in early mechanical failure. Between March 2003 and September 2005, 69 TKA procedures were performed by the computer navigated technique. The postoperative outcome of this cohort was compared with the same number of TKAs done by the traditional technique. The lower limb anatomical axis was determined in all cases pre- and postoperatively by weight-bearing anteroposterior (AP) and lateral full length X-rays. The positions of femoral and tibial components were recorded. Comparing the data in the navigation group on the AP view, 96.6% of femoral and 96.9% of tibial components and on the lateral view in 95.4% of femoral and in 95.4% of tibial components, the overall postoperative axis in 95.4% fell in the range considered in the literature as optimal. In the traditional group on the AP view, 75.7% of femoral and 68.1% of tibial components and on the lateral view 81.8% of femoral and 63.6% of tibial components, the overall postoperative axis in 60.6% fell between the values considered optimal in the literature. It seems to be proven that the computer navigated total knee arthroplasty technique ensures positioning of components significantly more precisely compared with the traditional surgical method. Accuracy of navigation depends on the software used, on the correct detection of anatomical reference points, and on a potentially uneven thickness of the cement layer during final insertion of the components. The computer navigated technique does not substitute professional skill and experience, since it merely transmits information for the surgeon. The decision is in the hands of the doctor during the entire procedure. The real benefits of the computer navigated technique require further research and can be determined only after long-term analyses. PMID:17115156

Sólyom, László; Szendrõi, Miklós

2006-01-01

106

Minimally invasive total hip arthroplasty: in opposition.  

PubMed

At the Knee Society Winter Meeting in 2003, Seth Greenwald and I debated about whether there should be new standards (ie, regulations) applied to the release of information to the public on "new developments." I argued for the public's "right to know" prior to the publication of peer-reviewed literature. He argued for regulatory constraint or "proving by peer-reviewed publication" before alerting the public. It is not a contradiction for me to currently argue against the public advertising of minimally invasive (MIS) total hip arthroplasty as not yet being in the best interest of the public. It is hard to remember a concept that has so captured both the public's and the surgical community's fancy as MIS. Patients are "demanding" MIS without knowing why. Surgeons are offering it as the next best, greatest thing without having developed the skill and experience to avoid the surgery's risks. If you put "minimally invasive hip replacement" into the Google search engine (http://www.google.com), you get 5,170 matches. If you put the same words in PubMed (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi), referencing the National Library of Medicine database, you get SEVENTEEN; none is really a peer-reviewed article. Most are 1 page papers in orthopedics from medical education meetings. On the other hand, there are over 6,000 peer-reviewed articles on total hip arthroplasty. Dr. Thomas Sculco, my couterpart in this debate, wrote an insightful editorial in the American Journal of Orthopedic Surgery in which he stated: "Although these procedures have generated incredible interest and enthusiasm, I am concerned that they may be performed to the detriment of our patients." I couldn't agree with him more. Smaller is not necessarily better and, when it is worse, it will be the "smaller" that is held accountable. PMID:15190556

Hungerford, David S

2004-06-01

107

Polyethylene wear in total hip arthroplasty.  

PubMed

Polyethylene wear increasingly has been blamed for osteolysis and granuloma formation after total joint arthroplasty. The authors evaluated the wear difference between bearing surfaces of stainless steel, cobalt chrome, and titanium alloy. They also compared cemented all-polyethylene molded cups with cemented metal-backed molded acetabular cups. These were compared with molded and machined polyethylene cups. Two patient groups were matched individually for gender, age, weight, and length of followup. Analyses were done using the technique of Livermore et al. The bearing surface evaluation consisted of 3 groups after matching, leaving 77 patients per group. Results showed linear wear rates of 0.06 mm per year, 0.05 mm per year, and 0.08 mm per year for stainless steel, cobalt chrome, and titanium alloy, respectively. The comparison between cemented molded metal-backed and nonmetal-backed acetabular components was not matched, with 134 metal-backed and 99 nonmetal-backed components. Results showed linear wear rates of 0.011 mm per year in the metal-backed group and 0.08 mm per year in the nonmetal-backed group. Results were statistically significant. These results indicate that the metal composition of the femoral bearing surface has minimal, if any, effect on the linear polyethylene wear rate. The method of polyethylene fabrication and the use of metal backing had a significant effect on the polyethylene wear rate in these patient groups. These results suggest that the compression-molded all-polyethylene acetabular component may be optimal for reducing polyethylene wear in total hip arthroplasty. PMID:7671498

Bankston, A B; Cates, H; Ritter, M A; Keating, E M; Faris, P M

1995-08-01

108

The merits of cell salvage in arthroplasty surgery: an overview.  

PubMed

Arthroplasty entails considerable exposure to allogenic blood transfusion. Cell salvage with washing is a contemporary strategy that is not universally used despite considerable potential benefits. We searched Embase and Medline to determine if blood salvage with washing during primary and/or revision hip and knee arthroplasty results in lower rates of transfusion and postoperative complications. We included 10 studies in our analysis, which we rated according to Downs and Black criteria. With primary knee arthroplasty, there was a reduction in transfusion rate from 22% to 76% and a 48% reduction in transfusion volume (n = 887). With primary hip arthroplasty, there was a reduction from 69% to 73% in transfusion rate and a 31% reduction in transfusion volume (n = 239). There was a significant decrease in length of hospital stay (9.6 v. 13.6 d). Studies of revision arthroplasty reported a 31%-59% reduction in transfusion volume (n = 241). The available evidence demonstrates reduced exposure to allogenic blood with the use of salvage systems. Studies have been underpowered to detect differences in infection rates and other postoperative complications. Future cost analysis is warranted. PMID:24461268

Dusik, Chris J; Hutchison, Carol; Langelier, David

2014-02-01

109

Surgeon delivered psoas compartment block in total hip arthroplasty.  

PubMed

Total hip arthroplasty is associated with significant postoperative pain. A psoas compartment block is superior to other regional techniques in analgesia post THA. However, traditional methods of delivery are associated with serious complications. We present a technique of a surgeon delivered lumbar plexus block through injection at the portion of the iliopsoas seen intraoperatively. We randomised fifty-three consecutive patients into two groups. The group that received the block had an increased period prior to requesting supplementary analgesia and lower overall pain scores. There were no adverse effects. We have demonstrated the analgesic efficacy of Psoas Compartment Block performed during surgical access for total hip arthroplasty. This technique should be considered in the analgesic regimen for total hip arthroplasty. PMID:23937924

Green, Connor; Byrne, Ann Maria; O'Loughlin, Padhraig; Molony, Diarmuid; Harmon, Dominic; Masterson, Eric

2014-02-01

110

Isokinetic strength testing of minimally invasive total knee arthroplasty recovery.  

PubMed

Fifty patients underwent isokinetic muscle strength testing before surgery and at 6 weeks, 3 months, 6 months, and 1 year after unilateral total knee arthroplasty using the minisubvastus surgical technique. Quadriceps muscle strength returned to preoperative levels by 3 months postoperatively and was 17% stronger at 6 months and 30% stronger at 1 year than preoperative levels (P < .05). At 1 year, the quadriceps strength of the involved knee was equivalent to that of the uninvolved knee (P = .81). When the entire study population was subdivided by age, weight, sex, and the presence of arthritis in the uninvolved knee, each subgroup still had equivalent quadriceps strength between the involved and uninvolved knees. This prospective study demonstrated that the minisubvastus total knee arthroplasty technique led to a more rapid and more complete recovery of muscle strength than has been previously demonstrated after total knee arthroplasty with a medial parapatellar arthrotomy. PMID:19062250

Schroer, William C; Diesfeld, Paul J; Reedy, Mary E; LeMarr, Angela R

2010-02-01

111

[Early clinical and radiological results following cervical disc arthroplasty].  

PubMed

The aim of this study was to assess early results of anterior cervical decompression and arthroplasty for cervical disc disease. The results of operations of 32 patients (43 instrumented levels) were examined to assess clinical outcome, the restoration of disc height, postoperative lordosis, mobility of instrumented segment and complication rate. Clinical outcome evaluated with VAS score improved from 7.5 preoperatively to 2.7 post operation. There was improvement in disc height measured by Tureyen method of 48%, 5 degree restoration of lordosis per segment and average 5 degree mobility of operated segment. In two cases spontaneous fusion occurred. There were no loosening of prosthesis observed. Overall the study shows that early results of arthroplasty are clinically efficient and safe as fusion. Assessment of biomechanical advantages of arthroplasty demands further observation to compare if long-term results are superior to fusion. PMID:18092697

Pa?ciak, Marek; Wadek, Tomasz; Widuchowski, Jerzy; Grzywocz, Jerzy; Werner, Krystian; Swiderski, Micha?

2007-01-01

112

Cemented total hip arthroplasty: still relevant in the new millennium?  

PubMed

Total hip arthroplasty can be performed successfully using cement or cementless technology. Cemented femoral stems can achieve enduring long-term suvivorship as long as meticulous surgical technique is utilized and patient selection is appropriate. Cemented acetabular components should only be utilized in patients with less than 10 years of remaining life expectancy. Critical risk factors for cemented total hip arthroplasty include atrophic osteoarthrtis on the acetabular side and unfavorable femoral geometry for the femoral stem such as "the stove-pipe" canal. Rapid polyethylene wear and osteolysis are rarely seen in contemporary cemented total hip arthroplasty performed with a smooth, tapered, collarless femoral stem with a highly polished head and a well-designed acetabular component. PMID:12882245

Iorio, Richard; Kobayashi, Seneki

2003-01-01

113

Post impingement in posterior stabilised total knee arthroplasty.  

PubMed

Posterior stabilised implants are a well-proven treatment for patients requiring primary total knee arthroplasty. Concerns about the posterior stabilised (PS) design have been raised and recent studies suggest that the post-cam articulation can be an additional source of polyethylene wear debris. In this study, the authors report impingement of the tibial post against the patellar component in deep flexion in posterior stabilised total knee arthroplasty. Their data suggest that "post impingement" is associated with a raised joint line, patella infera, too anterior placement of the tibial component and a smaller femoral component size. "Post impingement" may lead to extensor mechanism problems and additional polyethylene wear and therefore may affect the longterm functional results of posterior stabilised total knee arthroplasty. PMID:15055317

Verborgt, Olivier; Victor, Jan

2004-02-01

114

Hip arthroscopy in patients with painful hip following resurfacing arthroplasty  

Microsoft Academic Search

Purpose  Determining the etiology of persistent groin pain after hip resurfacing arthroplasty (HRA) can be very challenging, even for\\u000a the experienced surgeon. The purpose of the present study was to evaluate the use of hip arthroscopy as a diagnostic and therapeutic\\u000a tool for the painful hip following resurfacing arthroplasty.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  In the present paper, the indications for arthroscopy and the arthroscopic findings

C. Pattyn; R. Verdonk; E. Audenaert

115

Patellofemoral Arthroplasty: A Systematic Review of the Literature  

PubMed Central

Identification and management of patients with isolated patellofemoral osteoarthritis are challenging. Many of these patients present at a young age and it is important to distinguish degenerative change in the patellofemoral articulation from the other various causes of anterior knee pain. Once the diagnosis of isolated patellofemoral arthrosis has been made non-operative and conservative surgical techniques should be exhausted fully before prosthetic arthroplasty is considered. This review focuses on the use of arthroplasty for isolated patellofemoral arthrosis, in particular comparing the use of total knee against selective patellofemoral joint replacements. PMID:22927894

Tarassoli, Payam; Punwar, Shahid; Khan, Wasim; Johnstone, David

2012-01-01

116

Emerging technologies in arthroplasty: additive manufacturing.  

PubMed

Additive manufacturing is an industrial technology whereby three-dimensional visual computer models are fabricated into physical components by selectively curing, depositing, or consolidating various materials in consecutive layers. Although initially developed for production of simulated models, the technology has undergone vast improvements and is currently increasingly being used for the production of end-use components in various aerospace, automotive, and biomedical specialties. The ability of this technology to be used for the manufacture of solid-mesh-foam monolithic and coated components of complex geometries previously considered unmanufacturable has attracted the attention of implant manufacturers, bioengineers, and orthopedic surgeons. Currently, there is a paucity of reports describing this fabrication method in the orthopedic literature. Therefore, we aimed to briefly describe this technology, some of the applications in other orthopedic subspecialties, its present use in hip and knee arthroplasty, and concerns with the present form of the technology. As there are few reports of clinical trials presently available, the true benefits of this technology can only be realized when studies evaluating the clinical and radiographic outcomes of cementless implants manufactured with additive manufacturing report durable fixation, less stress shielding, and better implant survivorship. Nevertheless, the authors believe that this technology holds great promise and may potentially change the conventional methods of casting, machining, and tooling for implant manufacturing in the future. PMID:24764230

Banerjee, Samik; Kulesha, Gene; Kester, Mark; Mont, Michael A

2014-06-01

117

Patellar options in revision total knee arthroplasty.  

PubMed

There are numerous options that need to be considered by the surgeon at the time of revision total knee arthroplasty (TKA). One needs to consider the reason for the revision, the type of patella in place, and the length of time the patella has been in place. The surgeon also needs to consider the status of the patellar bone stock, the stability of the patellar component (well-fixed or loose), and the component type (cemented or metal-backed). Assuming that the existing prosthesis is not metal-backed and has minimal PE wear, then it is preferable to retain a well-fixed all-PE cemented patellar button. However, if the button is metal-backed, then it probably is best to remove the button and replace it with an all-PE domed patellar component. Assuming more than 8 mm of patellar bone stock is remaining, it usually is best to cement an all-PE dome-shaped patella. However, if less than 8 mm is remaining, then that patient can be left with a patelloplasty, recognizing that this individual is going to continue with a high likelihood of anterior knee pain, subluxation, and poor functional results. In that situation, it may be preferable to consider a bone stock augmentation. PMID:14646744

Rorabeck, Cecil H; Mehin, Ramin; Barrack, Robert L

2003-11-01

118

Supracondylar nailing of distal femoral fractures after total Knee Arthroplasty  

Microsoft Academic Search

We present results of supracondylar nailing in six patients who suffered distal femoral fractures above total knee arthroplasty. The average age of patients was 68 (42-92) years. All six fractures healed in a satisfactory alignment in an average duration of 14.6 weeks. There were no wound infection, loss of reduction or implant failure. All patients had regained their previous range

A. Kumar; A. Ali; M. S. Butt

119

A novel total knee arthroplasty infection model in rabbits  

Microsoft Academic Search

Infection of biomaterial implants is an expensive and devastating complication of orthopaedic surgery historically ranging from less than 1% in primary total knee arthroplasty (TKA) to 10% in revision TKA. An in vivo animal model was developed to test the efficacy of innovative therapies for the prevention of biomaterial centered infections caused by methicillin-resistant Staphylococcus aureus bacteria (MRSA). Twenty-two New

Matthew R. Craig; Kornelis A. Poelstra; J. Christopher Sherrell; Michael S. Kwon; Etienne L. Belzile; Thomas E. Brown

2005-01-01

120

Calcium phosphate cement composites in revision hip arthroplasty  

Microsoft Academic Search

Loosening of the femoral component in a total hip arthroplasty with concomitant bone loss can pose a problem for revision surgery due to inadequate structure in the remaining femur. While impaction allografting has shown promise, it has also shown serious complications, especially with moderate to severe bone loss. It may be possible to stabilize the graft layer with a bioresorbable

Andrew D. Speirs; Thomas R. Oxland; Bassam A. Masri; Anoush Poursartip; Clive P. Duncan

2005-01-01

121

Isokinetic Strength Testing of Minimally Invasive Total Knee Arthroplasty Recovery  

Microsoft Academic Search

Fifty patients underwent isokinetic muscle strength testing before surgery and at 6 weeks, 3 months, 6 months, and 1 year after unilateral total knee arthroplasty using the minisubvastus surgical technique. Quadriceps muscle strength returned to preoperative levels by 3 months postoperatively and was 17% stronger at 6 months and 30% stronger at 1 year than preoperative levels (P < .05).

William C. Schroer; Paul J. Diesfeld; Mary E. Reedy; Angela R. LeMarr

2010-01-01

122

Predictors of prolonged hospital stays following hip and knee arthroplasty  

Microsoft Academic Search

Orthopaedic leaders face extraordinary pressures in a world of diminishing resources, aging baby boomers and escalating demands for hip and knee replacement surgeries. Never has the need for focused, proactive care to improve outcomes and avoid unnecessary hospital days been greater. In this study, risk factors associated with prolonged length of stay (LOS) were investigated for hip and knee arthroplasty

Valerie MacDonald; Pamella Ottem; Michael Wasdell; Rae Spiwak

2010-01-01

123

Functional analysis of cemented medial unicompartmental knee arthroplasty  

Microsoft Academic Search

Gait analysis was used to study patients who underwent cemented medial unicompartmental knee arthroplasty (UKA) for medial compartment degenerative knee disease. All had excellent clinical function of the operated knee, with minimal involvement of other joints. Ten patients met the inclusion criteria for this study. Gait findings from this study group, as well as those from a similar cohort of

Eric P. Chassin; Richard P. Mikosz; Thomas P. Andriacchi; Aaron G. Rosenberg

1996-01-01

124

Acetabular cup-siting device for total hip arthroplasty  

Microsoft Academic Search

A method for improving acetabular cup positioning at arthroplasty is introduced. The anatomic and engineering principles involved are explained. The device used for this method of siting is described. The method was tested in cadaver experiments and resulted in a 380% improvement of anteversion-retroversion position and a 370% improvement in abduction position over conventional siting. The value of this method

J. Doyle; P. Murray; P. O. Mahony; M. Farmer; A. C. Hooper

1989-01-01

125

Patella maltracking in posterior-stabilized total knee arthroplasty.  

PubMed

Maltracking of the patella component in total knee arthroplasty usually leads to complications such as subluxation, dislocation, fracture, excessive wear, or implant failure. After using a new posterior-stabilized total knee arthroplasty and a specific protocol for the patellofemoral articulation we determined the incidence of lateral retinacular release and patella complications. We retrospectively reviewed 255 consecutive primary posterior-stabilized total knee arthroplasties with an anatomic femoral component and a three-peg offset-dome patella. Component alignment was achieved using Whiteside's lines for the femoral component, the medial border of the tubercle for the tibial component, and previously reported techniques for the patella. Lateral release was performed in 15 knees (6.2%), most of which had excessive preoperative valgus (mean, 15 degrees). There were no reoperations for the patellofemoral joint at a mean followup of 3.7 years (range, 2-7 years). Two patients had asymptomatic osteonecrosis of the patella with complete radiolucent lines, and one patella fracture was treated with immobilization. We believe patella maltracking a largely avoidable problem in total knee arthroplasty. We found a low incidence of lateral retinacular release and patella complications using these components and this protocol for the patellofemoral articulation. PMID:16936588

Lachiewicz, Paul F; Soileau, Elizabeth S

2006-11-01

126

Structural characteristics of impaction allografting for revision total hip arthroplasty  

Microsoft Academic Search

BackgroundThe impaction allografting procedure for treatment of failed hip reconstructions has shown promising but variable results. The objective of this study was to compare the structural characteristics of revision total hip arthroplasty constructs with impaction allografting (cement+morsellized bone) with all-cement and all-morsellized bone constructs.

Marcus C. Robinson; Göran Fernlund; R. M. Dominic Meek; Bassam A. Masri; Clive P. Duncan; Thomas R. Oxland

2005-01-01

127

Physiotherapy-led arthroplasty review clinic: a preliminary outcomes analysis.  

PubMed

Objective With the rising demand for Orthopaedics in the healthcare sector, service delivery innovations need to be explored to accommodate the increasing workload. Senior Musculoskeletal Physiotherapists have the specialised skills in the assessment of musculoskeletal conditions to determine the impact of surgery on patient outcomes. The aim of the present study was to compare outcomes between a physiotherapy-led arthroplasty review clinic (PT clinic) and the traditional model of orthopaedic surgeon review (OS clinic) after hip and knee replacement. Methods This study was a retrospective case-controlled audit using a comprehensive database. Twenty-four patients who had a hip arthroplasty and 52 patients who had a knee arthroplasty were reviewed solely by the PT clinic at 3, 6 and 12 months after surgical reviews. These patients were matched 1:2 against patients seen only by the OS clinic. The outcome measures included International Knee Score (IKS), Harris Hip Score (HHS) and the Short Form (SF)-12. Results There were no significant differences in HHS or SF-12 scores for patients after hip arthroplasty. Significant differences for knee arthroplasty were observed favouring the PT clinic; IKS, PT clinic 147.6 (37.07), OS clinic 135.4 (35.68), P?0.01, and physical component of the SF-12, PT clinic 41.98 (10.45), OS clinic 37.20 (10.44), P<0.01. Conclusion Implementation of a physiotherapy-led arthroplasty review clinic appears to be a safe and effective service alternative to reviews conducted by orthopaedic surgeons. What is known about the topic? Osteoarthritis (OA) is a leading cause of musculoskeletal pain and disability and the burden of the disease is rapidly increasing. Joint arthroplasty surgery is the mainstay of treatment for people with end-stage OA; it is a high-cost, high-volume procedure that dominates surgical wait lists around Australia. Long-term follow up is encouraged by the Arthroplasty Society of Australia and endorsed by the Australian Orthopaedics Association, but it is acknowledged that it is impossible to achieve this with solely orthopaedic surgeon reviews, an issue that is only going to worsen with the increased demand for surgery. Physiotherapists have become involved in many advanced scope roles within public health care, and emerging research suggests that patients are highly satisfied with their care in these types of clinics. What does this paper add? Although it has been shown that patients are satisfied in physiotherapy-led advanced clinics, there is a paucity of evidence in the outcomes of patients attending these clinics. Implementation of a physiotherapy-led arthroplasty review clinic demonstrated that outcome measures in this patient cohort were not compromised and, following knee joint arthroplasty, may even be improved. What are the implications for practitioners? The findings of this study indicate that joint review clinics involving physiotherapists acting in an advanced scope role are unlikely to compromise patient outcomes. The use of this role substitution on a broader scale can be recommended. PMID:25297119

Large, Kate E; Page, Carolyn J; Brock, Kim; Dowsey, Michelle M; Choong, Peter F M

2014-11-01

128

Assessing the Development Gap  

Microsoft Academic Search

Current report aims to identify major existing gaps in the four socio-economic dimensions (economic, human, environmental, and institutional) and to reveal those gaps which could potentially hinder social and economic integration of neighbor states with the EU. To achieve this, the authors aim to assess the existing trends in the size of the gaps across countries and problem areas, taking

Alexander Chubrik; Irina Denisova; Vladimir Dubrovskiy; Marina Kartseva; Irina Makenbaeva; Magdalena Rokicka; Irina Sinitsina; Michael Tokmazishvili

2007-01-01

129

Shoulder arthroplasty in osteoarthritis: current concepts in biomechanics and surgical technique  

PubMed Central

Shoulder arthroplasty is a technically demanding procedure to restore shoulder function in patients with severe osteoarthritis of the glenohumeral joint. The modern prosthetic system exploit the benefits of modularity and the availibility of additional sizes of the prosthetic components. In this paper we describe the biomechanics of shoulder arthroplasty and the technique for shoulder replacement including total shoulder arthroplasty (TSA) with all-polyethylene and metal-backed glenoid component, humeral head resurfacing and stemless humeral replacement. PMID:24251240

Merolla, G; Nastrucci, G; Porcellini, G

130

Imaging evaluation of complications of hip arthroplasty: review of current concepts and imaging findings.  

PubMed

Total hip arthroplasty has evolved along with improvements in component materials and design. The radiologist must accurately diagnose associated complications with imaging methods and stay informed about newer complications associated with innovations in surgical technique, prosthetic design, and novel materials. This pictorial essay presents clinical and imaging correlation of modern hip arthroplasty complications, with an emphasis on the most common complications of instability, aseptic loosening, and infection as well as those complications associated with contemporary metal-on-metal arthroplasty. PMID:23290697

Awan, Omer; Chen, Lina; Resnik, Charles S

2013-11-01

131

Total Hip Arthroplasty for Hip Fractures  

PubMed Central

Introduction: This study aimed to determine the dislocation and reoperation rate, functional outcomes, and the survival rate of the unique subset of very old but lucid and independent patients with hip fractures following a total hip arthroplasty (THA) and geriatric team-coordinated perioperative care. Method: Between 2000 and 2006, previously independent ambulatory patients ?80 years old presenting with an intracapsular hip fracture were given THAs under the care of an integrated orthopedic surgery–geriatric service. Their fracture-related complications, ambulation, mental status, and survival were followed for 5 to 11 years postinjury. Results: Five years postinjury, 57 (61.3%) patients of the original study group were living. In all, 3 (3.2%) patients had postoperative hip dislocations (and 2 patients had dislocation twice) and 2 reoperations were needed within the first postoperative month. There were no hip dislocations or reoperations after the first year. Radiographs obtained on 88% of the surviving patients at 5 years postoperatively showed that all remained unchanged from their immediate postoperative images. Nearly half of the patients were still able to ambulate as they did preoperatively and their mixed-model equation was statistically unchanged. Conclusion: This study of patients >80 years old with previously good functional status demonstrates that with appropriate surgical (best prosthesis, good operating technique, and regional anesthesia) and geriatric (pre- and postoperative assessments, close follow-up, medication adjustments, and fall-prevention instruction) care, they have few hip dislocations and reoperations, survive postfracture at least as long as their noninjured contemporaries, and continue to function and ambulate as they did prior to their injury. PMID:24660092

Monzon, Daniel Godoy; Iserson, Kenneth V.; Jauregui, Jose; Musso, Carlos; Piccaluga, Francisco; Buttaro, Martin

2014-01-01

132

Future Bearing Surfaces in Total Hip Arthroplasty  

PubMed Central

One of the most important issues in the modern total hip arthroplasty (THA) is the bearing surface. Extensive research on bearing surfaces is being conducted to seek an ideal bearing surface for THA. The ideal bearing surface for THA should have superior wear characteristics and should be durable, bio-inert, cost-effective, and easy to implant. However, bearing surfaces that are currently being implemented do not completely fulfill these requirements, especially for young individuals for whom implant longevity is paramount. Even though various new bearing surfaces have been investigated, research is still ongoing, and only short-term results have been reported from clinical trials. Future bearing surfaces can be developed in the following ways: (1) change in design, (2) further improvement of polyethylene, (3) surface modification of the metal, (4) improvement in the ceramic, and (5) use of alternative, new materials. One way to reduce wear and impingement in THA is to make changes in its design by using a large femoral head, a monobloc metal shell with preassembled ceramic liner, dual mobility cups, a combination of different bearing surfaces, etc. Polyethylene has improved over time with the development of highly crosslinked polyethylene. Further improvements can be made by reinforcing it with vitamin E or multiwalled carbon nanotubes and by performing a surface modification with a biomembrane. Surface modifications with titanium nitride or titanium niobium nitride are implemented to try to improve the metal bearings. The advance to the fourth generation ceramics has shown relatively promising results, even in young patients. Nevertheless, further improvement is required to reduce fragility and squeaking. Alternative materials like diamond coatings on surfaces, carbon based composite materials, oxidized zirconium, silicon nitride, and sapphire are being sought. However, long-term studies are necessary to confirm the efficacy of these surfaces after enhancements have been made with regard to fixation technique and implant quality. PMID:24605198

2014-01-01

133

Infection after primary total hip arthroplasty.  

PubMed

The number of primary total hip arthroplasties (THAs) performed in the United States each year continues to climb, as does the incidence of infectious complications. The changing profile of antibiotic-resistant bacteria has made preventing and treating primary THA infections increasingly complex. The goal of this review was to summarize (1) the published data concerning the risk of surgical site infection (SSI) after primary THA by type of bacteria and (2) the effect of potentially modifying factors. The Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, EMBASE, Web of Science, and PubMed were searched. Studies dated between 2001 and 2011 examining primary THA in adults were included. Meta-analysis of the collected data was performed. The pooled SSI rate was 2.5% (95% confidence interval [Cl], 1.4%-4.4%; P<.001; n=28,883). The pooled deep prosthetic joint infection (PJI) rate was 0.9% (95% Cl, 0.4%-2.2%; P<.001; n=28,883). The pooled rate of methicillin-resistant Staphylococcus aureus SSI was 0.5% (95% Cl, 0.2%-1.5%; P<.001; n=26,703). This is approximately 20% of all SSI cases. The pooled rate of intraoperative bacterial wound contamination was 16.9% (95% Cl, 6.6%-36.8%; P=.003; n=2180). All these results had significant heterogeneity. The postoperative risk of SSI was significantly associated with intraoperative bacterial surgical wound contamination (pooled rate ratio, 2.5; 95% Cl, 1.4%-4.6%; P=.001; n=19,049). PMID:24762833

Lindeque, Bennie; Hartman, Zach; Noshchenko, Andriy; Cruse, Margaret

2014-04-01

134

Unusual prosthetic femoral head fracture in total hip arthroplasty: ceramic on polyethylene articulation.  

PubMed

A 68-year-old man with a previous right total hip arthroplasty presented with acute pain in the right hip, and no associated trauma was reported. The previous hybrid arthroplasty consisted of a ceramic femoral head articulating on an ultra-high-molecular-weight polyethylene liner. The unusual diagnosis of fractured ceramic femoral head was made and an urgent revision arthroplasty was performed to remove the ceramic bearing as well as all implants that may have come into contact with the ceramic. This case report highlights the material properties of ceramics in total hip arthroplasties as well as the importance of regular follow-up in these patients. PMID:24515234

Tucker, Damien; Acharya, Mehool

2014-01-01

135

In-Hospital Outcomes after Hemiarthroplasty versus Total Hip Arthroplasty for Isolated Femoral Neck Fractures  

PubMed Central

Background: Previous studies suggest total hip arthroplasty may have some benefits compared to hemi-arthroplasty for displaced intracapsular femoral neck fractures in patients more than 60 years of age. The primary research question of our study was whether in-hospital adverse events, post-operative length of stay (LOS) and mortality in patients 60 year of age or older differed between total hip and hemi-arthroplasty for femoral neck fracture. Methods: We obtained data on 82951 patients more than 60 years of age with an isolated femoral neck fracture treated with either hemi-arthroplasty or total hip arthroplasty in 2009 or 2010 from the National Hospital Discharge Survey (NHDS) database. The International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9, CM) was used to code diagnoses, comorbidities, complications, and procedures. Results: Controlling for demographics and comorbidities, patients treated with hemi-arthroplasty had a 40% (95% CI 1.4-1.5) higher risk of adverse events compared to patients treated with a total hip arthroplasty. Length of stay and in-hospital mortality did not differ between these groups. Conclusions: The observed advantage for total hip arthroplasty might reflect greater infirmity in hemi-arthroplasty patients that was not accounted for by ICD-9 codes alone. PMID:25386574

Voskuijl, Timothy; Neuhaus, Valentin; Kinaci, Ahmet; Vrahas, Mark; Ring, David

2014-01-01

136

Evaluation of Component Positioning in Primary Total Hip Arthroplasty Using an Imageless Navigation Device Compared With Traditional Methods  

Microsoft Academic Search

Acetabular orientation affects the success of total hip arthroplasty. Computer-assisted navigation systems may reduce positional errors. Total hip arthroplasty results were analyzed using an imageless navigation system. We hypothesized that reliability and accuracy would improve. One hundred forty-nine total hip arthroplasties were performed using minimally invasive surgical techniques in 3 cohorts: manual (n = 53), initial navigation cases (n =

Brian C. Najarian; John E. Kilgore; David C. Markel

2009-01-01

137

The gap gene network  

PubMed Central

Gap genes are involved in segment determination during the early development of the fruit fly Drosophila melanogaster as well as in other insects. This review attempts to synthesize the current knowledge of the gap gene network through a comprehensive survey of the experimental literature. I focus on genetic and molecular evidence, which provides us with an almost-complete picture of the regulatory interactions responsible for trunk gap gene expression. I discuss the regulatory mechanisms involved, and highlight the remaining ambiguities and gaps in the evidence. This is followed by a brief discussion of molecular regulatory mechanisms for transcriptional regulation, as well as precision and size-regulation provided by the system. Finally, I discuss evidence on the evolution of gap gene expression from species other than Drosophila. My survey concludes that studies of the gap gene system continue to reveal interesting and important new insights into the role of gene regulatory networks in development and evolution. PMID:20927566

2010-01-01

138

GapZappers  

NSDL National Science Digital Library

In this online Flash activity students use their knowledge of addition of fractions and equivalent forms to navigate 15 levels of play. Each level progresses in difficulty and includes gaps measured in meters that students must fill in using fractional pieces to enable the lizard to move on in the field of play. Once the gap is filled, check the gap and the lizard will move on showing the fractional equation that solved the problem.

King, Colleen

2013-01-01

139

Metal-on-Metal Hip Resurfacing Arthroplasty  

PubMed Central

Background Metal-on-metal (MOM) hip resurfacing arthroplasty (HRA) is in clinical use as an appropriate alternative to total hip arthroplasty in young patients. In this technique, a metal cap is placed on the femoral head to cover the damaged surface of the bone and a metal cup is placed in the acetabulum. Objectives The primary objective of this analysis was to compare the revision rates of MOM HRA using different implants with the benchmark set by the National Institute of Clinical Excellence (NICE). The secondary objective of this analysis was to review the literature regarding adverse biological effects associated with implant material. Review Methods A literature search was performed on February 13, 2012, to identify studies published from January 1, 2009, to February 13, 2012. Results The revision rates for MOM HRA using 6 different implants were reviewed. The revision rates for MOM HRA with 3 implants met the NICE criteria, i.e., a revision rate of 10% or less at 10 years. Two implants had short-term follow-ups and MOM HRA with one of the implants failed to meet the NICE criteria. Adverse tissue reactions resulting in failure of the implants have been reported by several studies. With a better understanding of the factors that influence the wear rate of the implants, adverse tissue reactions and subsequent implant failure can be minimized. Many authors have suggested that patient selection and surgical technique affect the wear rate and the risk of tissue reactions. The biological effects of high metal ion levels in the blood and urine of patients with MOM HRA implants are not known. Studies have shown an increase in chromosomal aberrations in patients with MOM articulations, but the clinical implications and long-term consequences of this increase are still unknown. Epidemiological studies have shown that patients with MOM HRA implants did not have an overall increase in mortality or risk of cancer. There is insufficient clinical data to confirm the teratogenicity of MOM implants in humans. Conclusions Metal-on-metal HRA can be beneficial for appropriately selected patients, provided the surgeon has the surgical skills required for performing this procedure. Plain Language Summary There are many young patients with hip diseases who need to have hip replacement surgery. Although a traditional hip replacement is an acceptable procedure for these patients, some surgeons prefer using a newer technique in young patients called hip resurfacing. In this technique, instead of removing the head of the femoral bone, a metal cap is placed on the femoral head to cover the damaged surface of the bone and a metal cup is placed in the hip socket, similar to the cups used in traditional hip replacement. The analysis of the revision rates (i.e., how soon and in how many patients the surgery needs to be redone) and safety of resurfacing implants showed that generally these implants can last 10 years or more for the majority of young people. Good outcomes can be expected when skilled surgeons perform the surgery in properly selected patients. However, since these implants are made of metal (cobalt and chromium alloy), there is concern about excess metal debris production due to friction between the 2 metal components leading to high levels of metal ions in the blood and urine of patients. The production of metal debris may result in inflammation in the joint or development of a benign soft tissue mass leading to implant failure. However, it has been shown that this risk can be reduced by proper positioning of the implant and the careful selection of patients for this procedure. Little is known about the long-term biological effects of high levels of metal ions in the blood and urine of patients who have received metal implants. There is concern about potential increases in the risk of cancer and the risk of fetal abnormalities, but these effects have not been established yet. However, since cobalt and chromium can pass the placental barrier, implants that are not metal-on-metal are recommended for women at childbearing ages if they

Sehatzadeh, S; Kaulback, K; Levin, L

2012-01-01

140

Minimum two-year outcomes of modular bicompartmental knee arthroplasty.  

PubMed

The purpose of this study was to determine the results of modular unlinked bicompartmental knee arthroplasty (BiKA) for medial (or lateral) and patellofemoral arthritis. Twenty-nine modular BiKAs were followed prospectively, for a mean of 31 months (range, 24-46 months). Outcome measures included Knee Society Knee and Function Scores, KOOS, SF-12, and WOMAC, as well as radiographic assessments and implant survivorship. Two tail paired Student's t test was used to determine statistical differences between preoperative and postoperative scores. Mean range of motion (ROM) improved from 122° to 133° (P<0.001). There was a statistically significant improvement across all functional scores. One patient underwent conversion to total knee arthroplasty at 3 years for knee instability. There were no cases of patellar instability, implant loosening or wear, or progressive arthritis. PMID:23731787

Kamath, Atul F; Levack, Ashley; John, Thomas; Thomas, Beverly S; Lonner, Jess H

2014-01-01

141

Total hip arthroplasty in young patients with osteoarthritis.  

PubMed

Total hip arthroplasty (THA), an effective treatment for patients with end-stage arthritic hip conditions, provides dramatic pain relief, enhances mobility, and restores function.The success of THA in older patients, in concert with improvements in techniques and biomaterials, has stimulated demand for this procedure in younger, more active patients hoping to regain full activity. Although young age remains a relative contraindication to THA, the weight of this factor has diminished. Several investigators have reported results of low-friction arthroplasty in young patients. Unfortunately, the value of these studies is limited because of heterogeneous hip pathology in the younger groups, particularly given that preoperative pathology has proved to significantly affect implant survival. In this review of the literature, we focus on THA survival in young, active patients with a preoperative diagnosis of noninflammatory osteoarthritis. PMID:19377644

Daras, Mariza; Macaulay, William

2009-03-01

142

The sphericity of the bearing surface in total hip arthroplasty.  

PubMed

This study evaluated the sphericity of bearing surfaces in total hip arthroplasty. The out-of-roundness of metal femoral heads, the inner surface of polyethylene liners, and commercially available ball bearings was measured. The hip prostheses were obtained directly from the manufacturers. The sphericity of the bearing surfaces was significantly inferior to that of the ball bearings. The sphericity of the femoral head on the sagittal plane was inferior to that on the transverse plane. Several significant differences were found among different manufacturers. The sphericity of the femoral head on the sagittal plane and that of polyethylene significantly improved in 1999 and 2000 compared with those in 1995. Further improvement is desirable, however, because good sphericity is expected to prolong the functional performance of the prosthesis after total hip arthroplasty. PMID:11740758

Ito, H; Minami, A; Matsuno, T; Tanino, H; Yuhta, T; Nishimura, I

2001-12-01

143

Hemi-hamate arthroplasty for pilon fractures of finger  

PubMed Central

Background: Injury following proximal interphalangeal joint fracture dislocation is determined by the direction of force transmission and the position of the joint at the time of impact. Dorsal dislocations with palmar lip fractures are the most frequently encountered. The degree of stability is directly determined by the amount of middle phalangeal palmar lip involvement. Materials and Methods: Hemihamate arthroplasty procedure was used in the reconstruction in five cases with comminuted, impacted fractures of the proximal end of middle phalanx of the finger. Three patients were presented within 2 weeks; one patient came by one month and the other by three months following the injury. All patients presented with posterior subluxation of PIP joint. Results: Functional outcome following this procedure in both acute and chronic cases resulted in adequate restoration of joint stability and function. Conclusions: Hemihamate arthroplasty is an adjuvant in the treatment of unstable intra-articular pilon fracture involving PIP joint. PMID:22279280

Korambayil, Pradeoth M.; Francis, Anto

2011-01-01

144

Strategies for head and inlay exchange in revision hip arthroplasty  

PubMed Central

Due to the increasing number of total hip arthroplasties performed during the last three decades and the limited long-term survival, mainly because of wear, the number of revisions has increased during the last two years. If the implant itself is still considered to be stable, only head and inlay exchange is necessary. This requires comprehensive knowledge of the characteristics of the articulating materials by the surgeon as the wrong choice of wear couple can lead to early failure for a second time. The aim of this paper is to present considerations and strategies for head and inlay exchange in case of failure, either due to wear of the articulation material or of other indications for revision hip arthroplasty. PMID:21088833

Knahr, Karl

2010-01-01

145

The structural allograft composite in revision total knee arthroplasty.  

PubMed

Options in revision total knee arthroplasty with massive bone loss include arthrodesis, custom total knee arthroplasty, amputation, and revision with structural allograft-prosthesis composites. Advantages of structural allografts include their biologic potential, versatility, relative cost-effectiveness, bone stock restoration, and potential for ligamentous reattachment. Disadvantages include the risk of disease transmission and graft nonunion, malunion, collapse, or resorption. Extensive preoperative planning is required to rule out infection and to select properly the type and size of allograft and prosthetic implant. Implant designs with diaphyseal-engaging stems and increased prosthetic constraint often are required. The host site and allograft require meticulous preparation to maximize surface contact and mechanical interlock of the allograft and host. Allograft fixation must be rigid to allow for incorporation. Ligamentous reattachment to the allograft is most successful when done by a bone block technique. Common complications include instability and graft collapse. PMID:12068414

Dennis, Douglas A

2002-06-01

146

Easy Identification of Mechanical Axis during Total Knee Arthroplasty  

PubMed Central

Purpose We devised an intraoperatively identifiable mechanical axis (IIMA) as a reference of alignment in total knee arthroplasty (TKA). Materials and Methods Between February 2010 and January 2011, primary TKAs were consecutively performed on 672 patients (1007 knees) using an IIMA as a reference in the coronal plane. Results The alignment of the lower extremity improved from a mean of 11.4±6.7° (-10.3-34.4°) of varus preop. to 0.7±3.5° (-5.2-8.6°) immediately after surgery. Mean alignment of the femoral component in the coronal plane was 89.3±2.3° (83.4-97.2°) postop. and mean alignment of the tibial component was 90.4±2.2° (85.1-94.2°) postop. Conclusion This study showed that IIMA could be of considerable value as a new guider of alignment that is easily accessible and highly effective during total knee arthroplasty. PMID:24142658

Seo, Jai-Gon; Moon, Young-Wan; Kim, Sang-Min; Jo, Byung-Chul

2013-01-01

147

Trochanteric exostoses following total hip arthroplasty. A complication of trochanteric osteotomy.  

PubMed

Trochanteric osteotomy has long been a fundamental part of the technique of the Charnley low-friction arthroplasty. It is, however, not without its complications, the principal one of which is nonunion regardless of the type of fixation used. A previously undescribed complication requiring reoperation is reported with regard to eight cases of primary hip arthroplasty. PMID:1774575

Needoff, M; Milligan, G F

1991-01-01

148

The impact of health status on waiting time for major joint arthroplasty  

Microsoft Academic Search

This study was conducted to determine the impact of health status on waiting time for major joint arthroplasty in a universal publicly funded health system. Data were collected prospectively from a cohort of 553 patients waiting for total hip or total knee arthroplasty. The WOMAC and SF-36 health status instruments were administered at the time the patient was placed on

Karen D. Kelly; Don Voaklander; Gordon Kramer; D. William C. Johnston; Lynn Redfern; Maria E. Suarez-Almazor

2000-01-01

149

Influence of bi- and tri-compartmental knee arthroplasty on the kinematics of the knee joint  

Microsoft Academic Search

BACKGROUND: The cruciate ligaments are important stabilizers of the knee joint and determine joint kinematics in the natural knee and after cruciate retaining arthroplasty. No in vitro data is available to biomechanically evaluate the ability of the anterior cruciate ligament (ACL) to maintain knee joint kinematics after bicruciate-retaining bi-compartmental knee arthroplasty (BKA). Therefore, the objective of the current study was

Markus Wünschel; JiaHsuan Lo; Torsten Dilger; Nikolaus Wülker; Otto Müller

2011-01-01

150

Bone-membrane interface in aseptic loosening of total joint arthroplasties  

Microsoft Academic Search

In 19 patients who underwent revision arthroplasty for aseptic loosening of total joint arthroplasty, specimens were taken at the time of operation to include the bone-membrane interface. In 16 (84%) of the specimens, sufficient visualization of the interface was possible to allow histologic interpretation. In 13 of these cases, there was prominent evidence of classic bone remodeling with osteoclastmediated resorption

R. M. Atkins; V. G. Langkamer; M. J. Perry; C. J. Elson; C. M. P. Collins

1997-01-01

151

Accuracy of haptic assessment of patellar symmetry in total knee arthroplasty1  

Microsoft Academic Search

Resection resulting in asymmetrically thick patellar arthroplasty in knee arthroplasty may lead to increased compression forces, wear, fracture, or loss of quadriceps power. Assessing the cut patella between the thumb and forefinger (haptic assessment) represents a convenient way to recognize asymmetry. In 2 test series, 8 orthopedic surgeons evaluated 24 precut solid foam patellae of varying asymmetric thickness by feeling

James K. DeOrio; John P. Peden

2004-01-01

152

Posterior Cruciate Ligament Removal Contributes to Abnormal Knee Motion during Posterior Stabilized Total Knee Arthroplasty  

E-print Network

Posterior Cruciate Ligament Removal Contributes to Abnormal Knee Motion during Posterior Stabilized Total Knee Arthroplasty Melinda J. Cromie,1,2 Robert A. Siston,1,2,3,4 Nicholas J. Giori,2,5 Scott L (20­608) following posterior stabilized total knee arthroplasty. The underlying biomechanical causes

Delp, Scott

153

Intraoperative Passive Kinematics of Osteoarthritic Knees before and after Total Knee Arthroplasty  

E-print Network

Intraoperative Passive Kinematics of Osteoarthritic Knees before and after Total Knee ArthroplastyScience (www.interscience.wiley.com). DOI 10.1002/jor.20163 ABSTRACT: Total knee arthroplasty is a successful procedure to treat pain and functional disability due to osteoarthritis. However, precisely how a total knee

Delp, Scott

154

Modeling early recovery of physical function following hip and knee arthroplasty  

Microsoft Academic Search

BACKGROUND: Information on early recovery after arthroplasty is needed to help benchmark progress and make appropriate decisions concerning patient rehabilitation needs. The purpose of this study was to model early recovery of physical function in patients undergoing total hip (THA) and knee (TKA) arthroplasty, using physical performance and self-report measures. METHODS: A sample of convenience of 152 subjects completed testing,

Deborah M Kennedy; Paul W Stratford; Steven E Hanna; Jean Wessel; Jeffrey D Gollish

2006-01-01

155

Early outcomes of patella resurfacing in total knee arthroplasty  

PubMed Central

Background Patella resurfacing in total knee arthroplasty is a contentious issue. The literature suggests that resurfacing of the patella is based on surgeon preference, and little is known about the role and timing of resurfacing and how this affects outcomes. Methods We analyzed 134,799 total knee arthroplasties using data from the Australian Orthopaedic Association National Joint Replacement Registry. Hazards ratios (HRs) were used to compare rates of early revision between patella resurfacing at the primary procedure (the resurfacing group, R) and primary arthroplasty without resurfacing (no-resurfacing group, NR). We also analyzed the outcomes of NR that were revised for isolated patella addition. Results At 5 years, the R group showed a lower revision rate than the NR group: cumulative per cent revision (CPR) 3.1% and 4.0%, respectively (HR = 0.75, p < 0.001). Revisions for patellofemoral pain were more common in the NR group (17%) than in the R group (1%), and “patella only” revisions were more common in the NR group (29%) than in the R group (6%). Non-resurfaced knees revised for isolated patella addition had a higher revision rate than patella resurfacing at the primary procedure, with a 4-year CPR of 15% and 2.8%, respectively (HR = 4.1, p < 0.001). Interpretation Rates of early revision of primary total knees were higher when the patella was not resurfaced, and suggest that surgeons may be inclined to resurface later if there is patellofemoral pain. However, 15% of non-resurfaced knees revised for patella addition are re-revised by 4 years. Our results suggest an early beneficial outcome for patella resurfacing at primary arthroplasty based on revision rates up to 5 years. PMID:19968604

Clements, Warren J; Miller, Lisa; Whitehouse, Sarah L; Graves, Stephen E; Ryan, Philip

2010-01-01

156

Outcomes of Total Joint Arthroplasty in HIV Patients  

PubMed Central

Background Advancement in human immunodeficiency virus (HIV) therapies has increased life expectancy. The need for joint replacement is expected to increase as this population develops degenerative changes from aging and avascular necrosis (AVN). Studies have shown a higher risk of peri-prosthetic joint infections (PJI) in HIV patients. However, these studies include a high percentage of hemophiliacs, which may be a confounding variable. With the advent of highly active anti-retroviral therapy (HAART) and evolving HIV demographics, we hypothesize the rate of PJIs in HIV patients are comparable to the general population. Methods We performed a retrospective cohort study using prospectively collected data from our arthroplasty database. We identified 24 HIV patients that underwent 31 primary hip and one primary knee arthroplasty between July 1, 2000 and September 30, 2012. Mean age was 50 years (range 31-74). Mean follow-up was 14 months (range 1.5-60). Results There were no PJIs in our HIV population. All HIV patients were non-hemophiliacs on HAART. Thirty-one total hip arthroplasties (THA) and one total knee arthroplasty were performed. Twenty-one HIV patients underwent THA for AVN. Eight patients had bilateral AVN. One patient needed revision for aseptic loosening. The mean CD4 count was 647 (194-1193). Mean viral load was undetectable in 19 patients and unavailable in five. Conclusions Our HIV population had a lower rate of PJI compared to infection rates in prior literature. Despite our limited patient population, our data suggests that well controlled HIV patients on HAART therapy with undetectable viral loads and CD4 >200 are at similar risk of PJI as the average population. PMID:25328467

Falakassa, Jonathan; Diaz, Alejandro; Schneiderbauer, Michaela

2014-01-01

157

Hammertoe surgery: arthroplasty, arthrodesis or plantar plate repair?  

PubMed

In cases of painful complex hammertoe deformity, there is no single approach that can be used in all circumstances. If conservative care fails, surgical management may include interphalangeal joint arthroplasty, arthrodesis, and/or plantar plate repair. The best and most pragmatic surgical plan must be patient-centered, taking the age, activity level, expectations of the patient, and precise etiology of the hammertoe deformity into account. PMID:22727377

Kernbach, Klaus J

2012-07-01

158

Complications of Femoral Nerve Block for Total Knee Arthroplasty  

Microsoft Academic Search

Preemptive and multimodal pain control protocols have been introduced to enhance rehabilitation after total knee arthroplasty\\u000a (TKA). We determined the complication rate associated with preoperative femoral nerve block (FNB) for TKA. Among 1018 TKA\\u000a operations, we performed 709 FNBs using a single-injection technique into the femoral nerve sheath and confirming position\\u000a with nerve stimulation before induction. After TKA, weightbearing as

Sanjeev Sharma; Richard Iorio; Lawrence M. Specht; Sara Davies-Lepie; William L. Healy

2010-01-01

159

Minimally Invasive Total Knee Arthroplasty with Image-Free Navigation  

Microsoft Academic Search

\\u000a Computer-assisted surgery (CAS) is beginning to emerge as one of the most important technologies in orthopedic surgery. Many\\u000a of the initial applications of this technology have focused on adult reconstructive surgery of the knee. The value of CAS\\u000a in total knee arthroplasty (TKA) has been established in many studies. Minimally invasive surgical (MIS) techniques for performing\\u000a TKA are also receiving

S. David Stulberg

160

Partial weightbearing is not necessary after cementless total hip arthroplasty  

Microsoft Academic Search

The purpose of this study was to evaluate the effects of partial and full weightbearing after cementless total hip arthroplasty\\u000a over a two year follow-up period. Fifty-nine women and 41 men (average age 61 years) received an uncemented Spotorno stem\\u000a and were randomised into a full and a partial weightbearing group. No significant difference was found between the groups\\u000a with regard

Max Markmiller; Thomas Weiß; Peter Kreuz; Axel Rüter; Gerhard Konrad

161

Fear in Arthroplasty Surgery: The Role of Race  

Microsoft Academic Search

Understanding the difference in perceived functional outcomes between whites and blacks and the influence of anxiety and pain\\u000a on functional outcomes after joint arthroplasty may help surgeons develop ways to eliminate the racial and ethnic disparities\\u000a in outcome. We determined the difference in functional outcomes between whites and blacks and assessed the influence of fear\\u000a and anxiety in total joint

Carlos J. Lavernia; Jose C. Alcerro; Mark D. Rossi

2010-01-01

162

Multilobulated popliteal cyst after a failed total knee arthroplasty  

Microsoft Academic Search

Popliteal cyst is a rare finding after total knee arthroplasty (TKA), but when present, it might indicate a malfunction of\\u000a the TKA related to generation of wear-particles, or loosening. We present a case of a multilobulated popliteal cyst developing\\u000a in a patient 8 years after primary TKA. The cyst was associated with a mechanical prosthetic loosening. The primary complaint\\u000a of the

Biagio Moretti; Vittorio Patella; Elyazid Mouhsine; Vito Pesce; Antonio Spinarelli; Raffaele Garofalo

2007-01-01

163

Combined unicompartmental knee arthroplasty and anterior cruciate ligament reconstruction  

Microsoft Academic Search

Purpose  Patients presenting anterior cruciate ligament (ACL) deficiency and isolated osteoarthritis of the medial compartment are\\u000a treated either with biplanar osteotomy or with total knee arthroplasty (TKA). However, these patients between the forties\\u000a and fifties are often very active in daily life and feel limited due to their knee. In order to follow the idea of preserving\\u000a as much as possible

Marco Tinius; Pierre Hepp; Roland Becker

164

Vibroacoustography for the assessment of total hip arthroplasty  

PubMed Central

OBJECTIVES: This paper proposes imaging with 3-dimensional vibroacoustography for postoperatively assessing the uncovered cup area after total hip arthroplasty as a quantitative criterion to evaluate implant fixation. METHODS: A phantom with a bone-like structure covered by a tissue-mimicking material was used to simulate a total hip arthroplasty case. Vibroacoustography images of the uncovered cup region were generated using a two-element confocal ultrasound transducer and a hydrophone inside a water tank. Topological correction based on the geometry of the implant was performed to generate a 3-dimensional representation of the vibroacoustography image and to accurately evaluate the surface. The 3-dimensional area obtained by the vibroacoustography approach was compared to the area evaluated by a 3-dimensional motion capture system. RESULTS: The vibroacoustography technique provided high-resolution, high-contrast, and speckle-free images with less sensitivity to the beam incidence. Using a 3-dimensional-topology correction of the image, we accurately estimated the uncovered area of the implant with a relative error of 8.1% in comparison with the motion capture system measurements. CONCLUSION: Measurement of the cup coverage after total hip arthroplasty has not been well established; however, the covered surface area of the acetabular component is one of the most important prognostic factors. The preliminary results of this study show that vibroacoustography is a 3-dimensional approach that can be used to postoperatively evaluate total hip arthroplasty. The favorable results also provide an impetus for exploring vibroacoustography in other bone or implant surface imaging applications. PMID:23778334

Kamimura, Hermes A. S.; Wang, Liao; Carneiro, Antonio A. O.; Kinnick, Randall R.; An, Kai-Nan; Fatemi, Mostafa

2013-01-01

165

Sports Activity After Short-Stem Hip Arthroplasty  

Microsoft Academic Search

Background: No data are available about the sports activity of patients with bone-conserving short-stem hip implants.Hypothesis: Patients can return to a good level of sports activity after implantation of a short-stem hip implant.Study Design: Case series; Level of evidence, 4.Methods: The sports activity level of 68 patients (76 hips) after short-stem hip arthroplasty was assessed for a minimum of 2

Florian Schmidutz; Stefan Grote; Matthias Pietschmann; Patrick Weber; Farhad Mazoochian; Andreas Fottner; Volkmar Jansson

2012-01-01

166

(Parallel GAP) A GAP4 Package  

E-print Network

) . . . . . . . 16 1.10 Modifying the GAP kernel . . . . 17 2 Slave Listener 18 2.1 Slave Listener CommandsSemiEchelonMatrix) . . . 39 5.6 Caching slave task outputs (ParSemiEchelonMat revisited) . . 42 5.7 Agglomerating tasks

Cooperman, Gene

167

Applications of porous tantalum in total hip arthroplasty.  

PubMed

Porous tantalum is an alternative metal for total joint arthroplasty components that offers several unique properties. Its high volumetric porosity (70% to 80%), low modulus of elasticity (3 MPa), and high frictional characteristics make it conducive to biologic fixation. Tantalum has excellent biocompatibility and is safe to use in vivo. The low modulus of elasticity allows for more physiologic load transfer and relative preservation of bone stock. Because of its bioactive nature and ingrowth properties, tantalum is used in primary as well as revision total hip arthroplasty components, with good to excellent early clinical results. In revision arthroplasty, standard and custom augments may serve as a structural bone graft substitute. Formation of a bone-like apatite coating in vivo affords strong fibrous ingrowth properties and allows for substantial soft-tissue attachment, indicating potential for use in cases requiring reattachment of muscles and tendons to a prosthesis. Development of modular components and femoral stems also is being evaluated. The initial clinical data and basic science studies support further investigation of porous tantalum as an alternative to traditional implant materials. PMID:17077337

Levine, Brett; Della Valle, Craig J; Jacobs, Joshua J

2006-11-01

168

Metallosis following knee arthroplasty: a histological and immunohistochemical study.  

PubMed

Metallosis represents a rare and severe complication of knee replacement surgery. It is caused by the infiltration and accumulation of metallic debris into the peri-prosthetic structures, deriving from friction between metallic prosthetic components. In knee arthroplasty, this event generally occurs as a result of polyethylene wear of the tibial or metal-back patellar component. The real incidence of metallosis is still unknown, although it seems to be more frequent in hip than in knee arthroplasty. The metallic debris induces a massive release of cytokines from inflammatory cells, making a revision necessary whenever osteolysis and loosening of the prosthesis occur. We report four patients who underwent revision of their knee arthroplasty because of severe metallosis. In one of these patients, polyethylene wear had determined friction between the metal-back patellar component and the anterior portion of the femoral component. In the remaining three cases, metallosis was caused by friction between the femoral and tibial prosthetic metal surfaces, resulting from full-thickness wear of the tibial polyethylene. T lymphocytes were activated by metal particles present in periprosthetic membranes. In all patients, one-stage revision was necessary, with rapid pain disappearance and a complete functional recovery of the knee joint. PMID:21978703

Schiavone Panni, A; Vasso, M; Cerciello, S; Maccauro, Giulio

2011-01-01

169

Insall Award paper. Why are total knee arthroplasties failing today?  

PubMed

The incidence of failure after knee replacement is low, yet it has been reported that more than 22,000 knee replacements are revised yearly. The purpose of the current study was to determine current mechanisms of failure of total knee arthroplasties. A retrospective review was done on all patients who had revision total knee arthroplasty during a 3-year period (September 1997-October 2000) at one institution. The preoperative evaluation in conjunction with radiographs, laboratory data, and intraoperative findings were used to determine causes of failure. Two hundred twelve surgeries were done on 203 patients (nine patients had bilateral surgeries). The reasons for failure listed in order of prevalence among the patients in this study include polyethylene wear, aseptic loosening, instability, infection, arthrofibrosis, malalignment or malposition, deficient extensor mechanism, avascular necrosis in the patella, periprosthetic fracture, and isolated patellar resurfacing. The cases reviewed included patients who had revision surgery within 9 days to 28 years (average, 3.7 years) after the previous surgery. More than half of the revisions in this group of patients were done less than 2 years after the index operation. Fifty percent of early revision total knee arthroplasties in this series were related to instability, malalignment or malposition, and failure of fixation. PMID:12439231

Sharkey, Peter F; Hozack, William J; Rothman, Richard H; Shastri, Shani; Jacoby, Sidney M

2002-11-01

170

Infection prevention methodologies for lower extremity total joint arthroplasty.  

PubMed

Despite advances in our understanding of surgical site infections following total joint arthroplasty, this serious surgical complication continues to represent a substantial economic burden for the patient, the treating institution and the healthcare system. After increasing for the past decade, infection rates have stabilized at 1.6%; however, the total cost is projected to increase with the total number of revision procedures performed. A systematic review of the literature was performed to identify studies that assess the efficacy of pre-, peri- and post-operative infection prevention strategies in the setting of total hip or knee arthroplasty. Preference was given to randomized-controlled trials, data from national registries and meta-analyses within the past 5 years; however, all relevant articles were included in this analysis. The results of the literature search returned 549 articles that addressed infection in total joint arthroplasty, of which 71 specifically addressed infection prevention. Topics that were addressed included the CDC recommendations, skin preparation techniques, hair removal techniques, surgical draping techniques, operative dress, operating room ventilation, operating room traffic and antibiotic utilization. Newer infection prevention techniques, such as preoperative antiseptic scrubbing, are affected and may help reduce the infection rate, while traditionally accepted methods of prophylaxis such as laminar-flow operating rooms and body exhaust suits may raise the infection rate. PMID:23480090

Kapadia, Bhaveen H; Pivec, Robert; Johnson, Aaron J; Issa, Kimona; Naziri, Qais; Daley, Jacqueline A; Mont, Michael A

2013-03-01

171

obesity on the risk for total hip or knee arthroplasty. Clin Orthop  

E-print Network

To the Editor: We read with great interest the article ‘‘Role of Obesity on the Risk for Total Hip or Knee Arthroplasty’ ’ by Bourne et al. [1] in the December 2007 issue of CORR. The authors state increasing obesity was associated with increased relative risk for hip or knee arthroplasty. They found almost 75 % of total hip arthroplasty recipients and 88 % of total knee arthroplasty recipients were overweight or obese whereas the percentage of overweight or obese people for the Canadian population is 51.4%. These percentages could reflect a relationship between obesity and the risk of hip and knee arthroplasties, but there are no data regarding the etiologic factors leading to obesity in these patients. Arthrosis of the hip or the knee causes pain in the affected joint and typically results in a

Clin Orthop Relat Res; Sarper Gursu Md; Kerem Aydin Md; S. Gursu; K. Aydin

2008-01-01

172

Confronting the Achievement Gap  

ERIC Educational Resources Information Center

This article talks about the large achievement gap between children of color and their white peers. The reasons for the achievement gap are varied. First, many urban minorities come from a background of poverty. One of the detrimental effects of growing up in poverty is receiving inadequate nourishment at a time when bodies and brains are rapidly…

Gardner, David

2007-01-01

173

Advanced rapidity gap trigger  

E-print Network

Nubmer of phisically interesting processes is charachterized by the rapidity gaps. In reality, this gaps is filled by uderlying events with high (more than 0.75 for higgs) probability. In this paper we purpose a way to detect this shadowed events with aim to raise the number of rare events.

Abramovsky, V A

2004-01-01

174

Bridging the spirituality gap  

Microsoft Academic Search

An identifiable 'spirituality gap' exists between the lived experience of mental health difficulties, frequently spoken of in spiritual terms, and the professional expertise of mental health practitioners from whom we might seek help. This paper contrasts the lived experience of suicidality with the academic and professional discipline of suicidology to show that this gap arises from a scientific commitment to

David Webb

2005-01-01

175

21. Newfound Gap Road, last pullout before gap, North Carolina ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

21. Newfound Gap Road, last pullout before gap, North Carolina side. - Great Smoky Mountains National Park Roads & Bridges, Newfound Gap Road, Between Gatlinburg, TN & Cherokee, NC, Gatlinburg, Sevier County, TN

176

Generation gaps in engineering?  

E-print Network

There is much enthusiastic debate on the topic of generation gaps in the workplace today; what the generational differences are, how to address the apparent challenges, and if the generations themselves are even real. ...

Kim, David J. (David Jinwoo)

2008-01-01

177

Success of clinical pathways for total joint arthroplasty in a community hospital.  

PubMed

Clinical pathways for total joint arthroplasty have been implemented successfully during the past decade. We report the results of pathway use for primary elective total hip and total knee arthroplasty in a community teaching hospital. We evaluated pathway efficacy using patient data forms and the hospital's financial database. Before instituting the pathway, the average length of stay was 4.41 days for patients having total hip arthroplasty and 3.92 days for patients having total knee arthroplasty. The average length of stay for patients having total hip arthroplasty decreased to 3.24 days and to 2.98 days for patients having total knee arthroplasty. Press Ganey Survey results showed high patient satisfaction rates before and after pathway initiation. Pathway implementation did not lead to increased complication rates or readmissions. Despite higher expected increases in the overall healthcare cost during the time of implementation (3 years), direct cost increases were limited to 3.48%. The key elements contributing to pathway success included preoperative patient education, standardized orders derived from evidence-based medicine, and a nurse practitioner who championed the pathway and ensured compliance. We recommend clinical pathways for patients having total joint arthroplasties to reduce length of stay, facilitate effective resource use, and preserve quality of care without compromising patient satisfaction or safety. PMID:17065839

Walter, Frank L; Bass, Nora; Bock, Gregory; Markel, David C

2007-04-01

178

Inception report and Gap analysis  

E-print Network

Inception report and Gap analysis Boiler inspection Riga, June 2004 #12;Inception report and gap analysis ­ boiler inspection Table of Content 1 INTRODUCTION ................................................................................................................................. 3 2 BOILER INSTALLATIONS ­ GAP ANALYSIS

179

SOUTHWEST REGIONAL GAP LAND COVER  

EPA Science Inventory

The Gap Analysis Program is a national inter-agency program that maps the distribution of plant communities and selected animal species and compares these distributions with land stewardship to identify gaps in biodiversity protection. GAP uses remote satellite imag...

180

There Are GAPS and There Are GAPS  

NSDL National Science Digital Library

Access to the article is free, however registration and sign-in are required. Guanine nucleotide-binding proteins (G proteins) transduce a very large number of cellular regulatory signals. Several recent papers have shown that the larger heterotrimeric G proteins are regulated by a class of molecules known as the RGS proteins (regulators of G protein-signaling family) that are analogous to the GAPs (GTPase activating proteins), which regulate small monomeric G proteins. Iyengar summarizes this evidence and discusses the mechanism of action of the RGS proteins.

Ravi Iyengar (Mount Sinai School of Medicine;Department of Pharmacology)

1997-01-03

181

Pulse lavage is inadequate at removal of biofilm from the surface of total knee arthroplasty materials.  

PubMed

In acute periprosthetic infection, irrigation and debridement with component retention has a high failure rate in some studies. We hypothesize that pulse lavage irrigation is ineffective at removing biofilm from total knee arthroplasty (TKA) components. Staphylococcus aureus biofilm mass and location was directly visualized on arthroplasty materials with a photon collection camera and laser scanning confocal microscopy. There was a substantial reduction in biofilm signal intensity, but the reduction was less than a ten-fold decrease. This suggests that irrigation needs to be further improved for the removal of biofilm mass below the necessary bioburden level to prevent recurrence of acute infection in total knee arthroplasty. PMID:24439797

Urish, Kenneth L; DeMuth, Peter W; Craft, David W; Haider, Hani; Davis, Charles M

2014-06-01

182

Coccidioidomycosis infection of a total knee arthroplasty in a nonendemic region.  

PubMed

Fungal prosthetic joint infections are rare and difficult to treat. There is an ongoing discussion about the type and duration of antifungal treatment and the necessity of prosthesis removal. We report the first European case of an infected total knee arthroplasty with Coccidioides immitis. Treatment consisted of lifelong treatment with oral fluconazole at a dose of 400 mg/d, without total knee arthroplasty removal. After 6 months, the initial complaints of pain and swelling were completely resolved. This case report clearly states that a travel history and culturing for fungi are helpful in patients with persisting complaints after joint arthroplasty. PMID:22810005

Austen, Shennah; van der Weegen, Walter; Verduin, Cees M; van der Valk, Marc; Hoekstra, Henk J

2013-02-01

183

Ceramic Head Fracture in Ceramic-on-Polyethylene Total Hip Arthroplasty  

PubMed Central

Revision rates of total hip arthroplasty have decreased after introducing total hip arthroplasty (THA) using ceramic component, since ceramic components could reduce components wear and osteolysis. The fracture of a ceramic component is a rare but potentially serious event. Thus, ceramic on polyethylene articulation is gradually spotlighted to reduce ceramic component fracture. There are a few recent reports of ceramic head fracture with polyethylene liner. Herein, we describe a case of a ceramic head component fracture with polyethylene liner. The fractured ceramic head was 28 mm short neck with conventional polyethylene liner. We treated the patient by total revision arthroplasty using 4th generation ceramic on ceramic components. PMID:24142666

Nho, Jae-Hwi; Song, Ui-Seoub; Kim, Woo-Jong; Suh, You-Sung

2013-01-01

184

Outcome Assessment after Aptis Distal Radioulnar Joint (DRUJ) Implant Arthroplasty  

PubMed Central

Background: Conventional treatments after complicated injuries of the distal radioulnar joint (DRUJ) such as Darrach and Kapandji-Sauvé procedures have many drawbacks, which may eventually lead to a painful unstable distal ulna. The development of DRUJ prosthesis has significantly evolved over the past years. In this study, we assessed the outcome results of patients after DRUJ implant arthroplasty using the Aptis (Scheker) prosthesis. Methods: We identified 13 patients with 14 prosthesis during the past 10 years. Patients underwent DRUJ arthroplasty due to persistent symptoms of instability, chronic pain, and stiffness. Records and follow-up visits were reviewed to find the final post-operative symptoms, pain, range of motion, and grip strength with a mean follow-up of 12 months (range: 2-25 months). Also, patients were contacted prospectively by phone in order to administer the disabilities of the arm shoulder and hand (DASH), patient rated wrist evaluation (PRWE), and visual analogue scale (VAS), and to interview regarding satisfaction and progress in daily activities. Eleven patients out of 13 could be reached with a median follow-up time of 60 months (range: 2 to 102 months). Results: No patient required removal of the prosthesis. Only two patients underwent secondary surgeries in which both required debridement of the screw tip over the radius. The median DASH score, PRWE score, VAS, and satisfaction were 1.3, 2.5, 0, and 10, respectively. The mean range of flexion, extension, supination, and pronation was 62, 54, 51, and 64, respectively. Conclusions: Distal radioulnar joint injuries are disabling and patients usually undergo one or more salvage surgeries prior to receiving an arthroplasty. The Scheker prosthesis has shown satisfactory results with 100% survival rate in all reports. The constrained design of this prosthesis gives enough stability to prevent painful subluxation. PMID:25386579

Kachooei, Amir Reza; Chase, Samantha M; Jupiter, Jesse B

2014-01-01

185

Revision hip arthroplasty following recurrence of a phosphaturic mesenchymal tumor  

PubMed Central

We report the case of a recurrent phosphaturic mesenchymal tumor (PHT) of the right acetabulum in a 47-year-old man with a long history of hip pain. After primary excision of the PHT, successful remission was expected due to normal phosphate levels. Over a long period, a recurrence led to destruction of the acetabulum and loosening of the back plate of the hip prosthesis. One-year follow-up after revision arthroplasty revealed normal phosphate levels, and the patient reported no complaints. PMID:24963901

Dezfulian, Markus; Wohlgenannt, Othmar

2013-01-01

186

Revision hip arthroplasty following recurrence of a phosphaturic mesenchymal tumor.  

PubMed

We report the case of a recurrent phosphaturic mesenchymal tumor (PHT) of the right acetabulum in a 47-year-old man with a long history of hip pain. After primary excision of the PHT, successful remission was expected due to normal phosphate levels. Over a long period, a recurrence led to destruction of the acetabulum and loosening of the back plate of the hip prosthesis. One-year follow-up after revision arthroplasty revealed normal phosphate levels, and the patient reported no complaints. PMID:24963901

Dezfulian, Markus; Wohlgenannt, Othmar

2013-01-01

187

Examining Sex and Gender Disparities in Total Joint Arthroplasty  

Microsoft Academic Search

Background  Total joint arthroplasty (TJA) is remarkably successful for treating osteoarthritis: most patients see substantial gains in\\u000a function. However, there are considerable geographic, racial, and gender variations in the utilization of these procedures.\\u000a The reasons for these differences are complex.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  We examined sex and gender disparities in TJA.\\u000a \\u000a \\u000a \\u000a Methods  Through Medline\\/PubMed searches, we identified 632 articles and from these selected 61 for

Wendy M. Novicoff; Khaled J. Saleh

2011-01-01

188

Midterm results of total knee arthroplasty after high tibial osteotomy  

Microsoft Academic Search

Background  The outcome of total knee arthroplasty (TKA) after high tibial osteotomy (HTO) is still controversial. In order to determine\\u000a if osteotomy has any effect on this outcome we performed a medium-term review of a cohort of patients with knee osteoarthritis.\\u000a \\u000a \\u000a \\u000a Materials and methods  Thirty-two patients (38 knees), who were treated with a HTO before the TKA during the last 8 years, were

Konstantinos J. Kazakos; Christos Chatzipapas; Dionysios Verettas; Vasilios Galanis; Konstantinos C. Xarchas; Ioannis Psillakis

2008-01-01

189

Robotic-assisted unicompartmental knee arthroplasty: the MAKO experience.  

PubMed

Since its introduction, unicompartmental knee arthroplasty has been controversial because of poor early clinical outcomes due to implant design, bony fixation, surgical instrumentation, and technique. Improvements in surgical technique and implant design have resulted in improved results and greater survivorship. The ability to obtain accurate implant placement includes avoiding surgeon decisions leading to potential errors. These errors include alignment in the sagittal, coronal, and axial planes on each prepared condyle as well as the preservation of the joint line and the resulting overall limb alignment as something critical to obtaining a successful outcome. PMID:24274850

Roche, Martin

2014-01-01

190

Direct anterior approach for revision total hip arthroplasty  

PubMed Central

Revision total hip arthroplasty (THA) can be successfully performed through the direct anterior (DA) approach. Patient positioning, the surgical approach and specific instruments are important for obtaining adequate exposure. Acetabular exposure can be facilitated by capsular release and correct placement of retractors. Distal and proximal extension of the incision, as well as a femoral extended trochanteric osteotomy (ETO) can be performed to increase femoral exposure. The purposes of this article are to describe the DA approach, provide surgical techniques for revision THA through this approach, and describe the indications, contraindications and complications of this approach.

Manrique, Jorge; Heller, Snir; Hozack, William J.

2014-01-01

191

Dynamic soft tissue balancing in total knee arthroplasty.  

PubMed

Achieving optimal soft tissue balance intraoperatively is a critical element for a successful outcome after total knee arthroplasty. Although advances in navigation have improved the incidence of angular outliers, spatial distance measurements do not quantify soft tissue stability or degrees of ligament tension. Revisions caused by instability, malrotation, and malalignment still constitute up to one-third of early knee revisions. The development of integrated microelectronics and sensors into the knee trials during surgery allows surgeons to evaluate and act on real-time data regarding implant position, rotation, alignment, and soft tissue balance through a full range of motion. PMID:24684909

Roche, Martin; Elson, Leah; Anderson, Christopher

2014-04-01

192

The Surgical Apgar Score in Hip and Knee Arthroplasty  

Microsoft Academic Search

Background  A 10-point Surgical Apgar Score, based on patients’ estimated blood loss, lowest heart rate, and lowest mean arterial pressure\\u000a during surgery, was developed to rate patients’ outcomes in general and vascular surgery but has not been tested for patients\\u000a having orthopaedic surgery.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  For patients undergoing hip and knee arthroplasties, we asked (1) whether the score provides accurate risk stratification\\u000a for

Thomas H. Wuerz; Scott E. Regenbogen; Jesse M. Ehrenfeld; Henrik Malchau; Harry E. Rubash; Atul A. Gawande; David M. Kent

2011-01-01

193

Analysis of infection in shoulder arthroplasty: a multicentre study  

Microsoft Academic Search

Background  The purpose of this paper is to analyze 44 patients with infected shoulder arthroplasties from different centers.\\u000a \\u000a \\u000a \\u000a Methods  The patients were followed up for at least 2 years or until revision surgery from the year 1993 to 2008.\\u000a \\u000a \\u000a \\u000a Result  The mean follow-up of patients was 30 months. Microorganisms taken from 34 of the 44 patients were cultured. The most common\\u000a was Propionibacterium acnes (36%),

Rajkumar S. Amaravathi; Jean Kany; Myriam Melet; Denis Katz; Philippe Sauzieres; Philippe Valenti; Jean Marc Gandois

194

Spectral Gap Amplification  

E-print Network

A large number of problems in science can be solved by preparing a specific eigenstate of some Hamiltonian H. The generic cost of quantum algorithms for these problems is determined by the inverse spectral gap of H for that eigenstate and the cost of evolving with H for some fixed time. The goal of spectral gap amplification is to construct a Hamiltonian H' with the same eigenstate as H but a bigger spectral gap, requiring that constant-time evolutions with H' and H are implemented with nearly the same cost. We show that a quadratic spectral gap amplification is possible when H satisfies a frustration-free property and give H' for these cases. This results in quantum speedups for optimization problems. It also yields improved constructions for adiabatic simulations of quantum circuits and for the preparation of projected entangled pair states (PEPS), which play an important role in quantum many-body physics. Defining a suitable black-box model, we establish that the quadratic amplification is optimal for frustration-free Hamiltonians and that no spectral gap amplification is possible, in general, if the frustration-free property is removed. A corollary is that finding a similarity transformation between a stoquastic Hamiltonian and the corresponding stochastic matrix is hard in the black-box model, setting limits to the power of some classical methods that simulate quantum adiabatic evolutions.

Rolando D. Somma; Sergio Boixo

2011-10-11

195

Uncertainties in Gapped Graphene  

E-print Network

Motivated by graphene-based quantum computer we examine the time-dependence of the position-momentum and position-velocity uncertainties in the monolayer gapped graphene. The effect of the energy gap to the uncertainties is shown to appear via the Compton-like wavelength $\\lambda_c$. The uncertainties in the graphene are mainly contributed by two phenomena, spreading and zitterbewegung. While the former determines the uncertainties in the long-range of time, the latter gives the highly oscillation to the uncertainties in the short-range of time. The uncertainties in the graphene are compared with the corresponding values for the usual free Hamiltonian $\\hat{H}_{free} = (p_1^2 + p_2^2) / 2 M$. It is shown that the uncertainties can be under control within the quantum mechanical law if one can choose the gap parameter $\\lambda_c$ freely.

Eylee Jung; Kwang S. Kim; DaeKil Park

2011-07-27

196

Large head metal-on-metal cementless total hip arthroplasty versus 28mm metal-on-polyethylene cementless total hip arthroplasty: design of a randomized controlled trial  

PubMed Central

Background Osteoarthritis of the hip is successfully treated by total hip arthroplasty with metal-on-polyethylene articulation. Polyethylene wear debris can however lead to osteolysis, aseptic loosening and failure of the implant. Large head metal-on-metal total hip arthroplasty may overcome polyethylene wear induced prosthetic failure, but can increase systemic cobalt and chromium ion concentrations. The objective of this study is to compare two cementless total hip arthroplasties: a conventional 28 mm metal-on-polyethylene articulation and a large head metal-on-metal articulation. We hypothesize that the latter arthroplasties show less bone density loss and higher serum metal ion concentrations. We expect equal functional scores, greater range of motion, fewer dislocations, fewer periprosthetic radiolucencies and increased prosthetic survival with the metal-on-metal articulation. Methods A randomized controlled trial will be conducted. Patients to be included suffer from non-inflammatory degenerative joint disease of the hip, are aged between 18 and 80 and are admitted for primary cementless unilateral total hip arthroplasty. Patients in the metal-on-metal group will receive a cementless titanium alloy acetabular component with a cobalt-chromium liner and a cobalt-chromium femoral head varying from 38 to 60 mm. Patients in the metal-on-polyethylene group will receive a cementless titanium alloy acetabular component with a polyethylene liner and a 28 mm cobalt-chromium femoral head. We will assess acetabular bone mineral density by dual energy x-ray absorptiometry (DEXA), serum ion concentrations of cobalt, chromium and titanium, self reported functional status (Oxford hip score), physician reported functional status and range of motion (Harris hip score), number of dislocations and prosthetic survival. Measurements will take place preoperatively, perioperatively, and postoperatively (6 weeks, 1 year, 5 years and 10 years). Discussion Superior results of large head metal-on-metal total hip arthroplasty over conventional hip arthroplasty have been put forward by experts, case series and the industry, but to our knowledge there is no randomized controlled evidence. Conclusion This randomized controlled study has been designed to test whether large head metal-on-metal cementless total hip arthroplasty leads to less periprosthetic bone density loss and higher serum metal ion concentrations compared to 28 mm metal-on-polyethylene cementless total hip arthroplasty. Trial registration Netherlands Trial Registry NTR1399 PMID:18842151

Zijlstra, Wierd P; Bos, Nanne; van Raaij, Jos JAM

2008-01-01

197

Intraoperative CT navigation for glenoid component fixation in reverse shoulder arthroplasty.  

PubMed

CT navigation has been shown to improve component positioning in total shoulder arthroplasty. The technique can be useful in achieving strong initial fixation of the metal backed glenoid in reverse shoulder arthroplasty. We report a 61 years male patient who underwent reverse shoulder arthroplasty for rotator cuff arthropathy. CT navigation was used intraoperatively to identify best possible glenoid bone and to maximize the depth of the fixation screws that anchor the metaglene portion of the metal backed glenoid component. Satisfactory positioning of screws and component was achieved without any perforation or iatrogenic fracture in the scapula. CT navigation can help in maximizing the purchase of the fixation screws that dictate the initial stability of the glenoid component in reverse shoulder arthroplasty. The technique can be extended to improve glenoid component position [version and tilt] with the availability of appropriate software. PMID:23531710

Gavaskar, Ashok S; Vijayraj, K; Subramanian, Sd Muthukumar

2013-01-01

198

Intraoperative CT navigation for glenoid component fixation in reverse shoulder arthroplasty  

PubMed Central

CT navigation has been shown to improve component positioning in total shoulder arthroplasty. The technique can be useful in achieving strong initial fixation of the metal backed glenoid in reverse shoulder arthroplasty. We report a 61 years male patient who underwent reverse shoulder arthroplasty for rotator cuff arthropathy. CT navigation was used intraoperatively to identify best possible glenoid bone and to maximize the depth of the fixation screws that anchor the metaglene portion of the metal backed glenoid component. Satisfactory positioning of screws and component was achieved without any perforation or iatrogenic fracture in the scapula. CT navigation can help in maximizing the purchase of the fixation screws that dictate the initial stability of the glenoid component in reverse shoulder arthroplasty. The technique can be extended to improve glenoid component position [version and tilt] with the availability of appropriate software. PMID:23531710

Gavaskar, Ashok S; Vijayraj, K; Subramanian, SD Muthukumar

2013-01-01

199

Joint awareness in different types of knee arthroplasty evaluated with the Forgotten Joint score.  

PubMed

The purpose of this study was to validate the 'Forgotten Joint' score (FJS-12), a 12-item questionnaire designed to analyze the patient's ability to forget the joint in everyday life, in French and to compare the results of this Patient Reported Outcome (PRO) score in patients who had other than total joint arthroplasties. The score was compared in 122 patients that had either medial unicompartmental (N=51), patellofemoral (N=21) or total knee arthroplasty (N=50). After having validated the FJS-12 in French, a similar PRO was observed in unicompartmental and postero-stabilized total knee arthroplasty. Patellofemoral resurfacing had a significantly lower score than the two other types of arthroplasty, which can be explained by a significantly younger and smaller patient group. PMID:23688851

Thienpont, Emmanuel; Opsomer, Gaetan; Koninckx, Angelique; Houssiau, Frederic

2014-01-01

200

Comparison of total hip arthroplasty in osteoarthritis of mechanical and rheumatologic causes  

PubMed Central

Objective: To compare the use of uncemented implants in total hip arthroplasty in patients with rheumathologic diseases and mechanical osteoarthrosis. Methods: We retrospectively evaluated 196 patients who were operated by the Hip and Arthroplasty Surgery Group of the IOT-HCFMUSP between 2005 and 2009. Patients were divided into two groups: mechanical causes (165 patients) and rheumathologic causes (31 patients). Groups were compared between each other in age, gender and follow-up time. Osseointegration rate and percentage of failure in arthroplasty were evaluated. Results: No statistically significant difference was found in osseointegration rates (in both femoral and acetabular components) in both groups. The rates of revision surgery and implant survival also did not show statistically significant differences. Conclusion: The use of uncemented total hip arthroplasty did not show worse results in rheumathologic patients. Level of Evidence III, Retrospective Case Control Study. PMID:24644419

Ejnisman, Leandro; Leonhardt, Nathalia Zalc; Fernandes, Laura Fillipini Lorimier; Leonhardt, Marcos de Camargo; Vicente, José Ricardo Negreiros; Croci, Alberto Tesconi

2014-01-01

201

The biomechanics of knees at high flexion angles before and after Total Knee Arthroplasty  

E-print Network

Total Knee Arthroplasty (TKA) was initially developed to alleviate pain in the case of severe arthritis of the knee. Restoration of knee motion has been an on going issue for the last decade. Contemporary TKAs appear to ...

Most, Ephrat, 1970-

2004-01-01

202

Postoperative analgesia after total hip arthroplasty: patient-controlled analgesia versus transdermal fentanyl patch  

Microsoft Academic Search

Study ObjectiveTo determine whether a new transdermal fentanyl patch (TFP) is a good choice for the postoperative pain management of patients undergoing primary total hip arthroplasty compared with patient-controlled analgesia (PCA).

Vincent Minville; Vincent Lubrano; Vincent Bounes; Antoine Pianezza; Anna Rabinowitz; Claude Gris; Kamran Samii; Olivier Fourcade

2008-01-01

203

Investigation of in-vivo total knee arthroplasty biomechanics using a dual fluoroscopic imaging system  

E-print Network

While contempary total knee arthroplasty has been successful in improving the quality of life for those suffering from severe osteoarthritis, the function of these patients has not reached normal levels for their age group. ...

Suggs, Jeremy F. (Jeremy Floyd), 1976-

2007-01-01

204

Management bone loss of the proximal femur in revision hip arthroplasty: Update on reconstructive options  

PubMed Central

The number of revision total hip arthroplasties is expected to rise as the indications for arthroplasty will expand due to the aging population. The prevalence of extensive proximal femoral bone loss is expected to increase subsequently. The etiology of bone loss from the proximal femur after total hip arthroplasty is multifactorial. Stress shielding, massive osteolysis, extensive loosening and history of multiple surgeries consist the most common etiologies. Reconstruction of extensive bone loss of the proximal femur during a revision hip arthroplasty is a major challenge for even the most experienced orthopaedic surgeon. The amount of femoral bone loss and the bone quality of the remaining metaphyseal and diaphyseal bone dictate the selection of appropriate reconstructive option. These include the use of impaction allografting, distal press-fit fixation, allograft-prosthesis composites and tumor megaprostheses. This review article is a concise review of the current literature and provides an algorithmic approach for reconstruction of different types of proximal femoral bone defects.

Sakellariou, Vasileios I; Babis, George C

2014-01-01

205

[An unusual management of advanced gonarthrosis: total knee arthroplasty with posterior approach].  

PubMed

In this article, we present a 68 year-old female case admitted with complaints of a painful knee and walking difficulty with simultaneous advanced gonarthrosis and a huge osteochondroma in posterior distal femur which was adjacent to the vessel and nerve structures, who was treated with a single incision via posterior approach for tumor excision and arthroplasty. Simultaneous tumor excision and arthroplasty application were scheduled and the knee joint was reached via posterior popliteal approach. Hinged knee prosthesis was applied through the same incision following tumor excision. Two-stage surgical procedures can be an option for coexisting bone tumor and arthrosis. Arthroplasty can be performed following tumor excision. In our case, we managed two distinct different problems in a single session with a single approach. To the best of our knowledge, this is the first knee arthroplasty case performed with posterior approach. PMID:25036398

Keçeci, Burçin; Küçük, Levent

2014-01-01

206

In vivo knee biomechanics and implications for total knee arthroplasty implant design  

E-print Network

The overall objective of this thesis was to determine the limitations of contemporary Total Knee Arthroplasty (TKA) and to identify areas for future improvements. In line with this objective, the first goal was to quantify ...

Mangudi Varadarajan, Kartik, 1981-

2010-01-01

207

Skills Gaps in Australian Firms  

ERIC Educational Resources Information Center

This paper reports the results of a survey of more than 2000 managers examining perceptions of skills gaps in a range of Australian firms. It finds that three quarters report a skills gap, and almost one third report skills gaps across the whole organisation. Firm size and industry differences exist in perceptions of the effect of the skills gap

Lindorff, Margaret

2011-01-01

208

Outcomes of total knee replacement after patellofemoral arthroplasty.  

PubMed

There is increasing interest in the use of patellofemoral joint replacements and the cohort receiving them are the youngest of any of the groups of patients undergoing a knee arthroplasty. With more contemporary prostheses, progression of arthritis in other parts of the knee joint is becoming the predominant mechanism of failure. We conducted a multicenter retrospective comparative cohort study to discover whether the outcome of total knee replacement is compromised by prior patellofemoral joint arthroplasty. A total of 21 patients with a mean age of 61 years, who were revised from a patellofemoral joint replacement to a total knee replacement, were compared with a matched cohort of patients who underwent primary total knee replacement. At a mean follow-up of 2.4 years, the primary total knee replacement cohort had significantly better Oxford Knee Scores, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function scores, pain visual analog scores, and EQ-5D scores. There was no significant difference in patient satisfaction or EQ-5D visual analog scale.Our results indicate that although the revision of a patellofemoral joint replacement to a total knee replacement is a technically straightforward procedure, the eventual outcome may be less satisfactory when compared with a primary total knee replacement. PMID:23203512

Hutt, Jonathan; Dodd, Matthew; Bourke, Henry; Bell, Jonathan

2013-08-01

209

Anterior referencing versus posterior referencing in total knee arthroplasty.  

PubMed

Appropriate femoral component positioning and sizing is essential for proper kinematic function in total knee arthroplasty (TKA). Anterior or posterior referencing (AR or PR) are two major techniques for setting center of rotation and for balancing the sagittal plane of the arthroplasty. Both techniques have advantages and disadvantages. Minimally invasive surgical (MIS) TKA has added yet another aspect to intraoperative techniques and postoperative outcomes. A total of 100 consecutive patients undergoing unilateral MIS TKA were prospectively randomized to either AR or PR. Knee Society Scores, range of motion, SF-12, and strength testing by Cybex dynamometer were evaluated at standardized intervals postoperatively for 2 years. There were no statistically significant differences in surgical (incision length, surgical release, blood loss, surgical time, and length of stay) or clinical outcomes between two groups at all postoperative intervals (2 and 6 weeks, 3 and 6 months, and 1 and 2 years). Results demonstrate that both AR and PR are effective and can be used successfully during MIS TKA. PMID:24285366

Fokin, Alexander A; Heekin, Richard D

2014-08-01

210

Can pelvic tilting be ignored in total hip arthroplasty?  

PubMed Central

INTRODUCTION The orientation of acetabular component is influenced by pelvic tilt, body position and individual variation in pelvic parameters. Most post-operative adverse events may be attributed to malposition of the component in the functional position. There is evidence that orientation of the pelvis changes from the supine to standing position. Authors report a case of recurrent dislocation after total hip arthroplasty due to excessive pelvic tilting. PRESENTATION OF CASE A 69-year old female with coxarthrosis had undergone total hip replacement with recurrent dislocation of the hip on bearing weight in spite of using constrained acetabular component. DISCUSSION Our case report substantiates the influence of pelvic tilt, incurred by a sagittal deformity of spine, on dynamic orientation of the acetabular cup which was positioned in accordance with the anatomic landmarks alone. If the reference is only bony architecture and dynamic positions of the pelvis are not taken into account, improper functional orientation of the acetabular cup can result in sitting and standing positions. These can induce instability even in anatomically appropriately oriented acetabular component. CONCLUSION The sagittal position of pelvis is a key factor in impingement and dislocation after total hip arthroplasty. Pelvic tilting affects the position of acetabular component in the sagittal plane of the body as compared with its anatomic position in the pelvis. We suggest a preoperative lateral view of spine-pelvis, in upright and supine position for evaluation of a corrective adaptation of the acetabular cup accordingly with pelvic balance. PMID:25128730

Shon, Won Yong; Sharma, Vivek; keon, Oh jong; Moon, Jun Gyu; Suh, Dong Hun

2014-01-01

211

Optimizing femoral component rotation in total knee arthroplasty.  

PubMed

Femoral component rotation is important in total knee arthroplasty to optimize patellofemoral and tibiofemoral kinematics. More recently, the epicondylar axis has been cited as the definitive landmark for femoral component rotation. However, there are few studies to support the validity of this rotational landmark and its effect on the patellofemoral and tibiofemoral articulations. In the current study, a total knee arthroplasty was done in 11 knees from cadavers. The knees were tested with various femoral component rotations from 5 degrees internal rotation to 5 degrees external rotation referenced to the epicondylar axis and to the posterior femoral condyles. Each knee acted as its own internal control. The knees were actively ranged from 0 degrees to 100 degrees by a force on the quadriceps tendon in an Oxford knee simulator. Three-dimensional kinematics of all three components were measured whereas a multiaxial transducer imbedded in the patella measured patellofemoral forces. Femoral component rotation parallel to the epicondylar axis resulted in the most normal patellar tracking and minimized patellofemoral shear forces early in flexion. This optimal rotation also minimized tibiofemoral wear motions. These beneficial effects of femoral rotation were less reproducibly related to the posterior condyles. Rotating the femoral component either internal or external to the epicondylar axis worsened knee function by increasing tibiofemoral wear motion and significantly worsening patellar tracking with increased shear forces early in flexion. Based on the current study, the femoral component should be rotationally aligned parallel to the epicondylar axis to avoid patellofemoral and tibiofemoral complications. PMID:11716411

Miller, M C; Berger, R A; Petrella, A J; Karmas, A; Rubash, H E

2001-11-01

212

Are the relative indications for revision total knee arthroplasty changing?  

PubMed

There are relatively few data on the indications for revision total knee arthroplasty. The purpose of this study was to determine if the indications for revision have changed over the past decade. This is a retrospective review of demographic data and the indications for revision in two cohorts of patients by one surgeon. Patient gender, age, weight, time in situ, and reason for revision (eight categories) were recorded and analyzed by unpaired t-tests and chi-square tests. The first cohort was 81 revisions performed between 1990 and 1999. The second cohort was 116 revisions performed between 2000 and April 2008. There were no significant differences in the gender, mean age, mean weight, or mean time in situ between the two cohorts. There were more revisions for wear (p = .03) and instability (p = .06) in the recent cohort. There were significantly fewer revisions related to the patella prosthesis (p < .0001). There was no change in the number of revisions for infection between the two cohorts. The relative indications for revision total knee arthroplasty have changed over the past decade. Greater emphasis may be needed on improved balancing techniques to prevent instability and new bearing surfaces to decrease wear. PMID:19602334

Lachiewicz, Mark P; Lachiewicz, Paul F

2009-01-01

213

[Treatment of extensor mechanism rupture after total knee arthroplasty].  

PubMed

Disruption of the extensor mechanism is one of the most devastating complications in knee arthroplasty with a reported incidence between 0.17 and 2.5 %. Due to a high rate of subsequent complications and poor clinical results, every effort should be made to avoid extensor mechanism disruption. In cases of disruption however, the orthopaedic surgeons must be aware of non-operative and surgical treatment options and their indications, timing, outcome and limitations. Non-operative treatment is feasible in cases of incomplete disruption of the quadriceps tendon with an extension deficit of less than 20°. Complete disruption of the quadriceps tendon or rupture of the patellar tendon should be treated operatively. Therapeutic strategies include direct repair of the tendon in acute disruption without retraction. Retraction as well as soft tissue damage necessitates augmentation of the tendon. Frequently used endogenous augments are the semitendinosus tendon as well as the gastrocnemius muscle. Exogenous options are allografts of the Achilles tendon or structured extensor mechanism grafts and synthetic augments to support endogenous tendon repair. The clinical results after extensor mechanism failure following total knee arthroplasty are less favourable compared to ruptures in native knee joints. The most common complications are postoperative stretching and the maintenance of an active extensor lag. PMID:24129717

Bieger, R; Kappe, T; Wernerus, D; Reichel, H

2013-10-01

214

Advance pre-operative chlorhexidine reduces the incidence of surgical site infections in knee arthroplasty  

Microsoft Academic Search

Surgical site infections following elective knee arthroplasties occur most commonly as a result of colonisation by the patient’s\\u000a native skin flora. The purpose of this study was to evaluate the incidence of deep surgical site infections in knee arthroplasty\\u000a patients who used an advance cutaneous disinfection protocol and who were compared to patients who had peri-operative preparation\\u000a only. All adult

Michael G. Zywiel; Jacqueline A. Daley; Ronald E. Delanois; Qais Naziri; Aaron J. Johnson; Michael A. Mont

215

Conversion of total wrist arthroplasty to arthrodesis with a custom-made PEG.  

PubMed

Conversion of a failed total wrist arthroplasty to arthrodesis can be difficult. A custom-made titanium alloy peg was constructed to enable arthrodesis with the original arthroplasty components in situ. Two out of three patients were especially challenging cases with little bone available. Bony union was achieved in 2 to 3 months. The peg simplified a difficult revision situation and gave good, predictable results at follow-up. PMID:25097817

Reigstad, Ole; Røkkum, Magne

2014-08-01

216

Birmingham Mid-Head Resection Hip Arthroplasty in a Young Man with Gigantism  

Microsoft Academic Search

The Birmingham Mid-Head Resection (Smith & Nephew Ltd, Warwick, United Kingdom) arthroplasty is a new bone-conserving procedure that, like hip resurfacing, is used in younger, active patients. We present the case of a young man with Sotos syndrome (cerebral gigantism) with associated extraordinary stature (height, 2.16 m; weight, 157 kg) who underwent Birmingham Mid-Head Resection arthroplasty. The large stature of

Michael T. Murphy; Mark P. Shillington; Damon R. Mogridge; Simon F. Journeaux

217

GAP Program Overview  

NASA Technical Reports Server (NTRS)

NASA's General Aviation Propulsion (GAP) program is a cooperative program between government and industry. NASA's strategic direction is described by the "Three Pillars" and their Objectives as set forth by NASA Administrator Daniel S. Goldin. NASA's Three Pillars are: 1) Global Civil Aviation, 2) Revolutionary Technology Leaps, and 3) Access To Space.

Burkardt, Leo

1999-01-01

218

STEMMING the Gap  

ERIC Educational Resources Information Center

America has a gap when it comes to youth pursuing science and technology careers. In an effort to improve the knowledge and application of science, technology, engineering, and math (STEM), after-school programs can work in conjunction with formal in-school curriculum to improve science education. One organization that actively addresses this…

Kahler, Jim; Valentine, Nancy

2011-01-01

219

Closing the Performance Gap.  

ERIC Educational Resources Information Center

Describes how the principal of a K-2, 400-student suburban elementary school near Flint, Michigan, worked with her staff and superintendent to develop and implement a strategic plan to close the student achievement gap. Reports significant improvement in reading and math scores after 1 year. (PKP)

Riggins, Cheryl G.

2002-01-01

220

Seismic gaps and earthquakes  

Microsoft Academic Search

McCann et al. [1979] published a widely cited ``seismic gap'' model ascribing earthquake potential categories to 125 zones surrounding the Pacific Rim. Nishenko [1991] published an updated and revised version including probability estimates of characteristic earthquakes with specified magnitudes within each zone. These forecasts are now more than 20 and 10 years old, respectively, and sufficient data now exist to

Yufang Rong; David D. Jackson; Yan Y. Kagan

2003-01-01

221

Seismic gaps and earthquakes  

Microsoft Academic Search

McCann et al. [1979] published a widely cited “seismic gap” model ascribing earthquake potential categories to 125 zones surrounding the Pacific Rim. Nishenko [1991] published an updated and revised version including probability estimates of characteristic earthquakes with specified magnitudes within each zone. These forecasts are now more than 20 and 10 years old, respectively, and sufficient data now exist to

Yufang Rong; David D. Jackson; Yan Y. Kagan

2003-01-01

222

The Salary Gap.  

ERIC Educational Resources Information Center

The growing movement to privatize school management is a reason for comparing compensation and responsibilities in the private and public sectors. Despite the enormous salary gaps, public outrage over superintendents' salaries is common. Sensitive taxpayers might favor superintendent contracts including pay-for-performance factors resembling those…

Bushweller, Kevin

1994-01-01

223

GAP TESTS; COMPARISON BETWEEN UN GAP TEST AND CARD GAP TEST  

E-print Network

98-36 GAP TESTS; COMPARISON BETWEEN UN GAP TEST AND CARD GAP TEST by R. BRANKA and C. MICHOT, FRANCE (tel.: 33 3 44 55 65 19, fax: 33 3 44 55 65 10) ABSTRACT: UN gap test, type 1(a) or 2(a), is the recommended test in the acceptance procedure for transport of explosives in class 1. Up to the revision

Paris-Sud XI, Université de

224

New options for anticoagulation following total hip arthroplasty and total knee arthroplasty: new oral agents on the horizon.  

PubMed

Patients undergoing surgery for total hip arthroplasty (THA) or total knee arthroplasty (TKA) are at particularly high risk for developing venous thromboembolism (VTE). Despite the existence of effective therapies for VTE prevention, THA/TKA patients remain at risk for developing thrombi. Furthermore, the incidence of VTE is predicted to increase as an aging and increasingly obese population experiences joint damage necessitating THA and TKA. Current guidelines recommend the use of a wide range of antithrombotic agents in patients undergoing THA and TKA. These agents include vitamin K antagonists, low-molecular-weight heparins, fondaparinux, and the new oral anticoagulants. However, adherence to guidelines in clinical practice is disappointingly low. The limitations of traditional anticoagulants present management challenges following orthopedic surgery. Vitamin K antagonists present a number of drawbacks, including a narrow therapeutic window and unpredictable pharmacokinetics and pharmacodynamics. The subcutaneous route of administration of fondaparinux and low-molecular-weight heparins may make them unacceptable to patients in the outpatient setting. The introduction of a new generation of anticoagulants promises to address many of the drawbacks associated with the traditional agents. Clinical studies have shown the new oral anticoagulants to be as effective as traditional thromboprophylaxis, with good tolerability profiles. Clinical knowledge of these new agents will be essential to ensure that patients receive appropriate care following orthopedic surgery. This article will discuss the prevention of VTE after THA and TKA based on current evidence-based practice guidelines, the limitations of conventional anticoagulants, and the promise of new therapeutics. PMID:23086091

Amin, Alpesh

2012-08-01

225

Photonic Band Gap  

NSDL National Science Digital Library

Created by Boyang Liu and Professor Seng-Tiong Ho at Northwestern University, and presented by the NanoEd Resource Portal, this site covers the concept of the photonic band gap. Here, visitors will find a basic description of the concept, ideas of how to incorporate it into classroom activities, and a user's manual to walk students step-by-step through the concept. There is also a link to an interactive simulation (the link is labeled Open Visualization), which allows students to adjust the wavelength and color of the light source, particle size, and incident angle to view changes to the photonic band gap. This is a thorough and useful resource for any nanotechnology classroom.

Ho, Seng-Tiong; Liu, Boyang

2012-04-12

226

Bridging the Gap  

NSDL National Science Digital Library

A newly appointed joint hire in the College of Arts and Sciences, Department of Natural Sciences and the College of Education, Department of Middle/Secondary Education, was charged with the responsibility of bridging the communication gap between these two departments and colleges. To meet this challenge, four collaborative projects were developed between the Natural Sciences faculty and Middle/Secondary Education science students that will become formally established in future university courses.

Eason, Grace

2004-11-01

227

Filling the launch gap  

Microsoft Academic Search

Vehicles proposed to fill the gap in the U.S. space program's space transport needs for the next decade resulting from the January Challenger disaster, are discussed. Prior to the accident, the Air Force planned to purchase a Complementary Expendable Launch Vehicle system consisting of 10 single-use Titan-34D7 rockets. Another heavy lift booster now considered is the Phoenix H. Commercial launch

S. Hoeser

1986-01-01

228

Stair ambulation biomechanics following total knee arthroplasty: a systematic review.  

PubMed

The purpose of this review was to summarize the biomechanical adaptations during stair ambulation that occur after total knee arthroplasty (TKA). Articles were identified by searching PubMed and Web of Science. During stair ascent, knee flexion angle at heel strike and walking velocity were reduced in TKA subjects compared to controls. Results of other variables were not consistent between studies. During stair descent only one study found any differences for knee moments in the sagittal and frontal plane between TKA subjects and controls. Other results during stair descent were not consistent between studies. Differences in methods can partially explain discrepancies between studies in this review. More studies with consistent and improved methods are needed in order to provide better understanding of stair ambulation following TKA. PMID:24798192

Standifird, Tyler W; Cates, Harold E; Zhang, Songning

2014-09-01

229

Fasciotomy following total knee arthroplasty: beware of terrible outcome.  

PubMed

There is a paucity of literature on compartment pressure thresholds and complications following fasciotomy in postoperative Total Knee Arthroplasty (TKA) patients. The purpose of this study is to identify the postoperative course in a series of patients who had surgical decompression following TKA. We identified six patients who underwent fasciotomy for proven or suspected compartment syndrome following primary TKA between 2000 and 2010. The etiology of compartment syndrome was indirect (5 cases) vascular injury and one unknown. Complications after fasciotomy were: periprosthetic infection (2), foot drop (2), fasciitis (1), cellulitis (1), above the knee amputation due to periprosthetic infection (1). Currently, it is unknown if the same principles in the trauma patient apply for both diagnosis and treatment of compartment syndrome after TKA. We conclude that surgeons need to maintain a relatively higher threshold for performing a fasciotomy following TKA. PMID:23786987

Vegari, David N; Rangavajjula, Ashwin V; Diiorio, Timothy M; Parvizi, Javad

2014-02-01

230

Role of primary bearing type in revision total knee arthroplasty.  

PubMed

Although it has been shown that mobile- and fixed-bearing (FB) prostheses yield equivalent functional outcomes, wear patterns and debris types associated with mobile-bearing (MB) knees have been correlated to an increased prevalence of osteolysis. The complexity of revision surgery was compared between both designs. Several markers, including operative time, use of augmentation, bone grafts, and level of constraint, were analyzed. Data support that for failed total knee arthroplasty, there is a significant difference in mean time to revision between the MB (54.7 months) and FB types (80.6 months) (p ? 0.0001). MB knees more frequently required hinged implants during revision, potentially increasing the complexity of the procedure. This study raises concern for use of the MB implants, especially in younger patients who are more likely to require a future revision. PMID:23775543

Gupta, Rishi R; Bloom, Kevin J; Caravella, Joseph W; Shishani, Yousef F; Klika, Alison K; Barsoum, Wael K

2014-02-01

231

Alumina-on-Polyethylene Bearing Surfaces in Total Hip Arthroplasty  

PubMed Central

The long-term durability of polyethylene lining total hip arthroplasty (THA) mainly depends on periprosthetic osteolysis due to wear particles, especially in young active patients. In hip simulator study, reports revealed significant wear reduction of the alumina ceramic-on-polyethylene articulation of THA compared with metal-on-polyethylene bearing surfaces. However, medium to long-term clinical studies of THA using the alumina ceramic-on-polyethylene are few and the reported wear rate of this articulation is variable. We reviewed the advantages and disadvantages of ceramicon- polyethylene articulation in THA, hip simulator study and retrieval study for polyethylene wear, in vivo clinical results of THA using alumina ceramic-on-polyethylene bearing surfaces in the literature, and new trial alumina ceramic-onhighly cross linked polyethylene bearing surfaces. PMID:20224739

Jung, Yup Lee; Kim, Shin-Yoon

2010-01-01

232

Hip arthroplasty. Part 2: normal and abnormal radiographic findings.  

PubMed

This review addresses the normal and abnormal radiographic findings that can be encountered during the follow-up of patients with total hip arthroplasty (THA). The relative significance of different patterns of radiolucency, bone sclerosis, and component position is discussed. The normal or pathological significance of these findings is correlated with design, surface, and fixation of the prosthetic components. It is essential to have a good knowledge of expected and unexpected radiological evolution according to the different types of prostheses. This paper emphasizes the importance of serial studies compared with early postoperative radiographs during follow-up in order to report accurately any sign of prosthetic failure and trigger prompt specialist referral. Basic technical guidelines and schedule recommendations for radiological follow-up are summarized. PMID:19748001

Pluot, E; Davis, E T; Revell, M; Davies, A M; James, S L J

2009-10-01

233

Hip arthroplasty. Part 1: prosthesis terminology and classification.  

PubMed

Hip arthroplasty is an extremely common orthopaedic procedure and there is a wide array of implants that are in current use in the UK. The follow-up of patients who have undergone insertion of a hip prosthesis is shifting from a consultant-lead hospital service towards primary care. As this change in patient care continues it becomes increasingly important that an accurate description of the radiographic features is communicated to the primary-care practitioner so appropriate specialist input can be triggered. This review focuses on the terminology and classification of hip prostheses. This acts as a precursor for Part 2 of this series, which describes the normal and abnormal radiographic findings following hip prosthesis insertion. PMID:19748000

Pluot, E; Davis, E T; Revell, M; Davies, A M; James, S L J

2009-10-01

234

Primary total knee arthroplasty infected with Serratia marcescens.  

PubMed

We report an unusual case of a Serratia marcescens infection of total knee arthroplasty 4 weeks after the procedure following aspiration carried out on the ward (contrary to local protocol). This was successfully treated with thorough wound debridement, irrigation, change of the polyethylene liner and systemic antibiotics using intravenous meropenem for 3 weeks followed by oral ciprofloxacin for another 3 weeks. Our patient made an uneventful recovery and there was no reported recurrence of infection at 8 months of follow-up. We are unsure as to whether the infection was introduced at the time of the joint aspiration or was a complication of the initial procedure despite all the standard aseptic measures taken at the time of surgery. PMID:22987901

Mahmoud, Samer S S; Odak, Saurabh; Qazzafi, Zaman; McNicholas, M J

2012-01-01

235

Sexual activity after total hip arthroplasty: a motion capture study.  

PubMed

Relative risk of impingement and joint instability during sexual activities after total hip arthroplasty (THA) has never been objectively investigated. Hip range of motion necessary to perform sexual positions is unknown. A motion capture study with two volunteers was performed. 12 common sexual positions were captured and relevant hip joint kinematics calculated. The recorded data were applied to prosthetic hip 3D models to evaluate impingement and joint instability during motion. To explore the effect of acetabular component positioning, nine acetabular cup positions were tested. Four sexual positions for women requiring intensive flexion (> 95°) caused prosthetic impingements (associated with posterior instability) at 6 cup positions. Bony impingements (associated with anterior instability) occurred during one sexual position for men requiring high degree of external rotation (> 40°) combined with extension and adduction at all cup positions. This study hence indicates that some sexual positions could be potentially at risk after THA, particularly for women. PMID:24018159

Charbonnier, Caecilia; Chagué, Sylvain; Ponzoni, Matteo; Bernardoni, Massimiliano; Hoffmeyer, Pierre; Christofilopoulos, Panayiotis

2014-03-01

236

Sports activity after total hip and knee arthroplasty : specific recommendations concerning tennis.  

PubMed

Lower extremity total joint arthroplasties are among the most successful operations in orthopaedics. Presently, it appears that some patients wish to not only have general functions restored, but also desire the opportunity to return or continue on a high level of activity. This review summarises the literature concerning athletic activity, and tennis in particular, in relation to lower extremity total joint arthroplasties. Orthopaedic surgeons frequently recommend participation in low-impact sports such as swimming, walking, bicycling, bowling and golf. The patient's return to these recreational activities appears to be without problems. In contrast, there has been a general consensus from surgeons to avoid high-impact sports such as tennis and jogging after total joint arthroplasty, but there have been numerous studies that reported functional results being compatible with these activity levels. Conflicts emerge with some studies that describe lower survival rates for hip and knee arthroplasty in patients participating in high-impact sports. Most of these studies report that participation in sporting activities following total joint arthroplasty refers to increased polyethylene wear and debris, which could eventually result in implant failure. With recent advances in implant technology and surgical technique, the survival rates for modern prosthetic designs and patients with these high demands are promising. Various studies assessing the association between clinical outcome and participation in tennis did not demonstrate a harmful effect on implant survival rates. Although the majority of these studies do not reflect a true representation of the average patient undergoing total joint arthroplasty, more surgeons are confronted with the patients' desire to continue with sports activity. To optimise results, patients who demand higher levels of activity must be carefully selected, and must have the motivation and drive to optimise their results. In general, all patients should be encouraged to remain physically active to improve general health, maintain good bone quality, and improve implant fixation. There is still a need for prospective, randomised controlled studies concerning high activity and its impact on total joint arthroplasty. PMID:16796395

Seyler, Thorsten M; Mont, Michael A; Ragland, Phillip S; Kachwala, Munaf M; Delanois, Ronald E

2006-01-01

237

Surgical waste audit of 5 total knee arthroplasties  

PubMed Central

Background Operating rooms (ORs) are estimated to generate up to one-third of hospital waste. At the London Health Sciences Centre, prosthetics and implants represent 17% of the institution’s ecological footprint. To investigate waste production associated with total knee arthroplasties (TKAs), we performed a surgical waste audit to gauge the environmental impact of this procedure and generate strategies to improve waste management. Methods We conducted a waste audit of 5 primary TKAs performed by a single surgeon in February 2010. Waste was categorized into 6 streams: regular solid waste, recyclable plastics, biohazard waste, laundered linens, sharps and blue sterile wrap. Volume and weight of each stream was quantified. We used Canadian Joint Replacement Registry data (2008–2009) to estimate annual weight and volume totals of waste from all TKAs performed in Canada. Results The average surgical waste (excluding laundered linens) per TKA was 13.3 kg, of which 8.6 kg (64.5%) was normal solid waste, 2.5 kg (19.2%) was biohazard waste, 1.6 kg (12.1%) was blue sterile wrap, 0.3 kg (2.2%) was recyclables and 0.3 kg (2.2%) was sharps. Plastic wrappers, disposable surgical linens and personal protective equipment contributed considerably to total waste. We estimated that landfill waste from all 47 429 TKAs performed in Canada in 2008–2009 was 407 889 kg by weight and 15 272 m3 by volume. Conclusion Total knee arthroplasties produce substantial amounts of surgical waste. Environmentally friendly surgical products and waste management strategies may allow ORs to reduce the negative impacts of waste production without compromising patient care. Level of evidence Level IV, case series. PMID:23351497

Stall, Nathan M.; Kagoma, Yoan K.; Bondy, Jennifer N.; Naudie, Douglas

2013-01-01

238

Physical functioning four years after total hip and knee arthroplasty.  

PubMed

Our previous study showed that 6 months after total hip arthroplasty (THA) or total knee arthroplasty (TKA), patients reported having less difficulty with daily activities, showed better functional capacity, and performed activities in their natural environment faster compared to preoperatively. However, their actual daily activity level was not significantly improved. Six months is a rather short follow-up period and the discrepancy in recovery among different aspects of functioning might be explained by this limited duration of follow-up. The objective of the present study was to examine the recovery of different aspects of physical functioning at a follow-up nearly 4 years after THA/TKA. Special attention was given to the actual daily activity level, and whether it had increased 4 years after THA/TKA compared to 6 months postoperatively. Seventy-seven (35 hip, 42 knee) patients who were measured preoperatively and postoperatively (6 months after surgery) in a previous study were invited to participate; 44 patients (23 hip, 21 knee) agreed to participate. The 4-year follow-up data were compared with the preoperative and 6-month postoperative data. The daily activity level after 4 years was found to be actually lower than at 6 months post-surgery (128 min vs. 138 min activity per 24h; p-value 0.48). However, the patients continued to improve in other aspects of physical functioning. In conclusion, 4-year post-surgery patients continued to improve on perceived physical functioning, capacity, and performance of activities in daily life. However, even in this relatively healthy study population, patients did not adopt a more active lifestyle 4 years after surgery. PMID:23829981

Vissers, M M; Bussmann, J B; de Groot, I B; Verhaar, J A N; Reijman, M

2013-06-01

239

Traditions and myths in hip and knee arthroplasty.  

PubMed

Background and purpose - Traditions are passed on from experienced surgeons to younger fellows and become "the right way to do it". Traditions associated with arthroplasty surgery may, however, not be evidence-based and may be potentially deleterious to both patients and society, increasing morbidity and mortality, slowing early functional recovery, and increasing cost. Methods - We identified selected traditions and performed a literature search using relevant search criteria (June 2014). We present a narrative review grading the studies according to evidence, and we suggest some lines of future research. Results - We present traditions and evaluate them against the published evidence. Preoperative removal of hair, urine testing for bacteria, use of plastic adhesive drapes intraoperatively, and prewarming of the operation room should be abandoned-as should use of a tourniquet, a space suit, a urinary catheter, and closure of the knee in extension. The safety and efficacy of tranexamic acid is supported by meta-analyses. Postoperatively, there is no evidence to support postponement of showering or postponement of changing of dressings to after 48 h. There is no evidence to recommend routine dental antibiotic prophylaxis, continuous passive motion (CPM), the use of compression stockings, cooling for pain control or reduction of swelling, flexion of at least 90 degrees as a discharge criterion following TKA, or having restrictions after THA. We present evidence supporting the use of NSAIDs, early mobilization, allowing early travel, and a low hemoglobin trigger for transfusion. Interpretation - Revision of traditions and myths surrounding hip and knee arthroplasty towards more contemporary evidence-based principles can be expected to improve early functional recovery, thus reducing morbidity, mortality, and costs. PMID:25285615

Husted, Henrik; Gromov, Kirill; Malchau, Henrik; Freiberg, Andrew; Gebuhr, Peter; Troelsen, Anders

2014-12-01

240

The association between metal allergy, total hip arthroplasty, and revision  

PubMed Central

Background and purpose It has been speculated that the prevalence of metal allergy may be higher in patients with implant failure. We compared the prevalence and cause of revisions following total hip arthroplasty (THA) in dermatitis patients suspected to have contact allergy and in patients in general with THA. Furthermore, we compared the prevalence of metal allergy in dermatitis patients with and without THA. Materials and methods The Danish Hip Arthroplasty Registry (DHAR) contained detailed information on 90,697 operations. The Gentofte patch-test database contained test results for patients suspected of having allergic contact dermatitis (n = 18,794). Cases (n = 356) were defined as patch-tested dermatitis patients who also had primary THA performed. Two age- and sex-matched controls (n = 712) from the patch-test database were sought for each case. Results The prevalence of revision was similar in cases (12%) and in patients from the DHAR (13%). The prevalence of metal allergy was similar in cases and controls. However, the prevalence of metal allergy was lower in cases who were patch-tested after operation (6%) than in those who were patch-tested before operation (16%) (OR = 2.9; 95% CI = 1–8). Interpretation We found that the risk of surgical revision was not increased in patients with metal allergies and that the risk of metal allergy was not increased in cases who were operated, in comparison to controls. Despite some important study limitations, our observations add to the evidence that the risk of complications in metal allergic patients seems limited. PMID:19995314

2009-01-01

241

Spontaneous modular femoral head dissociation complicating total hip arthroplasty.  

PubMed

Modular femoral heads have been used successfully for many years in total hip arthroplasty. Few complications have been reported for the modular Morse taper connection between the femoral head and trunnion of the stem in metal-on-polyethylene bearings. Although there has always been some concern over the potential for fretting, corrosion, and generation of particulate debris at the modular junction, this was not considered a significant clinical problem. More recently, concern has increased because fretting and corrosive debris have resulted in rare cases of pain, adverse local tissue reaction, pseudotumor, and osteolysis. Larger femoral heads, which have gained popularity in total hip arthroplasty, are suspected to increase the potential for local and systemic complications of fretting, corrosion, and generation of metal ions because of greater torque at the modular junction. A less common complication is dissociation of the modular femoral heads. Morse taper dissociation has been reported in the literature, mainly in association with a traumatic event, such as closed reduction of a dislocation or fatigue fracture of the femoral neck of a prosthesis. This report describes 3 cases of spontaneous dissociation of the modular prosthetic femoral head from the trunnion of the same tapered titanium stem because of fretting and wear of the Morse taper in a metal-on-polyethylene bearing. Continued clinical and scientific research on Morse taper junctions is warranted to identify and prioritize implant and surgical factors that lead to this and other types of trunnion failure to minimize complications associated with Morse taper junctions as hip implants and surgical techniques continue to evolve. PMID:24972443

Talmo, Carl T; Sharp, Kinzie G; Malinowska, Magdalena; Bono, James V; Ward, Daniel M; LaReau, Justin

2014-06-01

242

Lack of impact of intravenous lidocaine on analgesia, functional recovery, and nociceptive pain threshold after total hip arthroplasty  

E-print Network

-operative intravenous lidocaine after total hip arthroplasty offers no beneficial effect on postoperative analgesia blood concentrations were measured at the end of administration. In both groups, postoperative analgesia perioperative IV lidocaine after total hip arthroplasty offers no beneficial effect on postoperative analgesia

Paris-Sud XI, Université de

243

Quality of intertrochanteric cancellous bone as predictor of femoral stem RSA migration in cementless total hip arthroplasty  

Microsoft Academic Search

In cementless total hip arthroplasty, osteoporosis may jeopardize the achievement of immediate stability and lead to migration of anatomically shaped femoral stems. Poor quality of proximal cancellous bone per se may also affect the rate of osseointegration. In a selected group of female total hip arthroplasty patients (mean age 64 years) with unremarkable medical history, intertrochanteric cancellous bone biopsy was

Niko Moritz; Jessica J. Alm; Petteri Lankinen; Tatu J. Mäkinen; Kimmo Mattila; Hannu T. Aro

2011-01-01

244

Extreme variations in racial rates of total hip arthroplasty for primary coxarthrosis: a population-based study in San Francisco  

Microsoft Academic Search

OBJECTIVES--To compare the incidence of all total hip arthroplasty, and total hip arthroplasty for primary coxarthrosis, among the Asian, black, Hispanic, and white populations living in one locale. METHODS--We identified all San Francisco residents who underwent total hip replacements (THR) in the 17 hospitals for adults within or near San Francisco County during a five year period. Preoperative pelvic radiographs

F T Hoaglund; C S Oishi; G G Gialamas

1995-01-01

245

The acetabular component in total hip arthroplasty. Evaluation of different fixation principles.  

PubMed

Initial stability is necessary for permanent fixation of acetabular cups. Biologic reactions to submicron particles such as localized bone resorption may lead to implant failure. The aim of the study was to evaluate different fixation principles of acetabular components. Four randomized studies and one case-control study were performed to evaluate different bone cements, different cup designs, use of ceramic coating or not, different type of screws and the need of additional screw fixation or not. Radiostereometry (RSA) makes it possible to analyze small translations and rotations of implants with a high accuracy. This method is suitable for evaluation of early stability and was used in four of the studies. Clinical and radiological follow-up were performed regularly. The cements were tested in the laboratory. 30 patients (mean age 71 years, range: 63-76) received total hip arthroplasties and were randomised to fixation with Boneloc (14) or Palacos cum gentamicin (16) bone cement. The curing temperature was 23 degrees lower for the Boneloc cement but the tensile strength was reduced and the elastic modulus was lower compared to Palacos. The proximal cup migration was greater in the Boneloc group up to 12 months (p 0.04) and these cups migrated medially in contrast to a small lateral migration seen in the Palacos group (p 0.04). Radiolucencies were more pronounced in the Boneloc group at 12 months (p 0.04). 155 patients (171 hips, mean age 50 years, range: 24-64) received uncemented hip arthroplasties. 84 hips were randomised to the PCA and 87 to the Harris-Galante I designs. The 10-year survival rates were 85% for the PCA and 99% for the Harris-Galante I cups (revision as end-point). The wear and clinical results did not differ. 43 patients (mean age 60 years, range 44-68) received uncemented porous cups with a titanium mesh in pure titanium (Harris-Galante II) and were randomised to additional fixation with either biodegradable screws (23, poly-L-lactic acid, PLLA) or screws made of titanium alloy (20). Increased proximal and medial-lateral translations (p 0.02, 0.04) but less rotation around the longitudinal axis (p 0.04) were seen in the PLLA group up to 2 years. There were also more pronounced radiolucencies anteriorly in this group at 2 years. The clinical results did not differ. 23 uncemented porous cups (Harris-Galante II) with hydroxyapatite-tricalciumphosphate coating (HA/TCP) were pair-wise matched to uncoated cups. Up to 2 years, decreased rotations around the horizontal axis were recorded in the HA/TCP-coated cups. Central postoperative gaps were more frequently seen in the HA/TCP group (p < 0.01), but at 2 years radiolucencies were more pronounced in the uncoated group (p < 0.01). The wear and clinical results did not differ. 62 patients (64 hips, mean age 56 years, range: 32-75) were randomized to porous Trilogy cups with (30) and without (34) cluster holes for additional screw fixation. Up to 2 years there were no differences in migration, wear, radiographic findings or clinical results. In conclusion Boneloc cement was associated with poor fixation due to inferior mechanical properties. The PLLA screws did not provide sufficient stability. Unacceptably high failure rates were recorded for the PCA cup. HA/TCP coating improved the fixation and the interface of porous cups. HA/TCP coated porous cups can be fixed without adjunctive screw fixation. PMID:10572504

Thanner, J

1999-08-01

246

Computer navigation vs conventional mechanical jig technique in hip resurfacing arthroplasty: a meta-analysis based on 7 studies.  

PubMed

The studies on the accuracy of femoral component in hip resurfacing arthroplasty with the help of computer-assisted navigation were not consistent. This study aims to assess at the functional outcomes after computer navigation in hip resurfacing arthroplasty by systematically reviewing and meta-analyzing the data, which were searched up to December 2011 in PubMed, MEDLINE, EMBASE, MetaMed, EBSCO HOST, and the Web site of Google scholar. Totally, 197 articles about hip resurfacing arthroplasty were collected; finally, 7 articles met the inclusion criteria and were included in this meta-analysis (520 patients with 555 hip resurfacing arthroplasty). The odds ratio for the number of outliers was 0.155 (95% confidence interval, 0.048-0.498; P < .003). In conclusion, this meta-analysis suggests that the computer-assisted navigation system makes the femoral component positioning in hip resurfacing arthroplasty easier and more precise. PMID:22771091

Liu, Hao; Li, Lin; Gao, Wei; Wang, Meilin; Ni, Chunhui

2013-01-01

247

Thermally induced strains and total shrinkage of the polymethyl-methacrylate cement in simplified models of total hip arthroplasty.  

PubMed

An evaluation of transient and stabilized strains in the cement mantle during polymerization was carried out in simplified cemented total hip arthroplasty (THA) model. A mathematical approach combined with a simple finite element simulation was used to compare measured and calculated stabilized strain values and to provide the Von Mises stresses at the stem/cement interface due to shrinkage related to temperature decrease after exothermal reaction. A second similar model was carried out to measure stem/cement/mold interfacial shear strength and dimensional changes of the cement mantle to obtain total shrinkage due to temperature decrease plus cement polymerization. The results indicated that positive strain peaks found during the exothermic stage of polymerization have the potential to produce pre-loading cracking. After the initial expansion, it was observed a progressive strain decrease pattern down to stabilized values that takes place near 2h after the cementation. Even though there is a great deal of dispersion in the measured stabilized strain values, in average those values match quite well with the numerical simulations, indicating 4,7 MPa von Mises interfacial stress due to thermal shrinkage. The total cement shrinkage leads to a negative radial stress of 11 MPa and 14 MPa von Mises interfacial stress. Finally, total shrinkage has the potential to enhance gaps in the cement/mold interface. PMID:23237878

Griza, Sandro; Ueki, Marcelo M; Souza, Dárcio H G; Cervieri, André; Strohaecker, Telmo R

2013-02-01

248

Formation of a large rice body-containing cyst following total hip arthroplasty  

PubMed Central

Background There are several well-described causes of a painful mass following total hip arthroplasty including polyethylene and metal wear debris, infection, expanding hematoma, dislocation, and synovial cysts. In addition to causing pain, these lesions, when large enough, may cause neurologic and vascular compromise. Rapid growth of the mass may clinically and radiographically resemble a sarcoma. Here, we report a case of a large painful hip mass which developed after total hip arthroplasty. The well-circumscribed mass was overlying and extending into the hip joint containing thousands of highly organized fibrin-containing “rice bodies”. To our knowledge, this is the first report of a large, highly organized (rice-body-containing) cyst complicating total hip arthroplasty. Case presentation A 55-year old Caucasian woman developed a large, slowly enlarging, painful hip mass 2 1/2?years after primary total hip arthroplasty. Clinically and radiographically, the lesion resembled a soft tissue sarcoma. Surgical removal identified a well-circumscribed mass extending into the hip joint containing thousands of highly organized fibrin-containing “rice bodies”. Conclusion Identification and excision of this “pseudotumor” following hip arthroplasty is important for obtaining a definitive diagnosis, ruling out malignancy or infection and relieving any potential compression on surrounding neurovascular structures. PMID:22698085

2012-01-01

249

Failed Reverse Total Shoulder Arthroplasty Caused by Recurrent Candida glabrata Infection with Prior Serratia marcescens Coinfection  

PubMed Central

This report describes a 58-year-old insulin-dependent diabetic male patient who initially sustained a proximal humerus fracture from a fall. The fracture fixation failed and then was converted to a humeral hemiarthroplasty, which became infected with Candida glabrata and Serratia marcescens. After these infections were believed to be cured with antibacterial and antifungal treatments and two-stage irrigation and debridement, he underwent conversion to a reverse total shoulder arthroplasty. Unfortunately, the C. glabrata infection recurred and, nearly 1.5 years after implantation of the reverse total shoulder, he had a resection arthroplasty (removal of all implants and cement). His surgical and pharmacologic treatment concluded with (1) placement of a tobramycin-impregnated cement spacer also loaded with amphotericin B, with no plan for revision arthroplasty (i.e., the spacer was chronically retained), and (2) chronic use of daily oral fluconazole. We located only three reported cases of Candida species causing infection in shoulder arthroplasties (two C. albicans, one C. parapsilosis). To our knowledge, a total shoulder arthroplasty infected with C. glabrata has not been reported, nor has a case of a C. glabrata and S. marcescens periprosthetic coinfection in any joint. In addition, it is well known that S. marcescens infections are uncommon in periprosthetic joint infections.

Skedros, John G.; Keenan, Kendra E.; Updike, Wanda S.; Oliver, Marquam R.

2014-01-01

250

Ileal interposition reduces blood glucose levels and decreases insulin resistance in a type 2 diabetes mellitus animal model by up-regulating glucagon-like peptide-1 and its receptor  

PubMed Central

This study is to explore the possible mechanism of ileal interposition (IT) treatment of glycemic control of the type 2 diabetes mellitus (T2DM) by establishing an IT animal model. Twelve T2DM rats (GK rats) of 8-week old were divided into GK IT surgery group (GK-IT) and GK sham group (GK-Sham). Six Wistar rats were used as the non-T2DM sham group (WS-Sham). Enzyme-linked immunosorbent assay was used to detect plasma insulin concentration and fasting pancreas glucagon-like peptide-1 (GLP-1) concentration changes. Homeostasis model assessment of insulin resistance was used to quantitatively measure insulin resistance. Glucagon-like peptide-1 receptor (GLP-1R) expression was detected by Western blotting. IT significantly decreased fasting blood glucose level and the oral glucose tolerance, and reduced insulin resistance of GK rats by increasing GLP-1 concentration and GLP-1R levels. The postoperative pancreatic ?-cell apoptosis rate of GK-Sham group was significantly higher than those in the GK-IT group and the WS-Sham group. IT significantly reduces blood glucose and decreases insulin resistance by up-regulating GLP-1 concentrations and GLP-1R levels, which may contribute to insulin secretion of pancreatic ?-cells and decreases apoptosis of pancreatic ?-cell. PMID:25120793

Sun, Xu; Zheng, Meizhu; Song, Maomin; Bai, Rixing; Cheng, Shi; Xing, Ying; Yuan, Huisheng; Wang, Pilin

2014-01-01

251

Cervical Arthroplasty for Moderate to Severe Disc Degeneration: Clinical and Radiological Assessments after a Minimum Follow-Up of 18 Months: Pfirrmann Grade and Cervical Arthroplasty  

PubMed Central

Purpose Clinical outcomes and radiologic results after cervical arthroplasty have been reported in many articles, yet relatively few studies after cervical arthroplasty have been conducted in severe degenerative cervical disc disease. Materials and Methods Sixty patients who underwent cervical arthroplasty (Mobi-C®) between April 2006 and November 2011 with a minimum follow-up of 18 months were enrolled in this study. Patients were divided into two groups according to Pfirrmann classification on preoperative cervical MR images: group A (Pfirrmann disc grade III, n=38) and group B (Pfirrmann disc grades IV or V, n=22). Visual analogue scale (VAS) scores of neck and arm pain, modified Oswestry Disability Index (mODI) score, and radiological results including cervical range of motion (ROM) were assessed before and after surgery. Results VAS and mean mODI scores decreased after surgery from 5.1 and 57.6 to 2.7 and 31.5 in group A and from 6.1 and 59.9 to 3.7 and 38.4 in group B, respectively. In both groups, VAS and mODI scores significantly improved postoperatively (p<0.001), although no significant intergroup differences were found. Also, cervical dynamic ROM was preserved or gradually improved up to 18 months after cervical arthroplasty in both groups. Global, segmental and adjacent ROM was similar for both groups during follow-up. No cases of device subsidence or extrusion were recorded. Conclusion Clinical and radiological results following cervical arthroplasty in patients with severe degenerative cervical disc disease were no different from those in patients with mild degenerative cervical disc disease after 18 months of follow-up. PMID:24954339

Oh, Chang Hyun; Kim, Do Yeon; Ji, Gyu Yeul; Kim, Yeo Ju; Hyun, Dongkeun; Kim, Eun Young; Park, Hyeonseon; Park, Hyeong-Chun

2014-01-01

252

Staged esophageal lengthening with internal and subsequent external traction sutures leads to primary repair of an ultralong gap esophageal atresia with upper pouch tracheoesophagel fistula.  

PubMed

Primary repair of very long gap esophageal atresia (EA) with almost complete absence of thoracic esophagus has usually been thought impossible. Thus, esophageal replacement with colon or gastric interposition seemed inevitable. In contrast, J. Foker described a technique of lengthening the pouches with traction sutures and making primary repair possible. To contribute clinical experience to this discussion, we report about esophageal elongation in a child with long gap EA and an upper pouch tracheoesophageal fistula (TEF). The patient presented as a preterm baby with a long gap EA of almost 9 vertebral bodies (7 cm) and additionally TEF on the upper pouch. Initially, he was treated with a gastrostomy and replogle suction of the upper pouch. Tracheoesophageal fistula was repaired, and the upper pouch brought from the neck into the thoracic inlet. At the same time thoracotomy was performed, and the lower esophageal segment mobilized and fixed to the prevertebral fascia under moderate tension. The tension reduced the gap between both pouches to about 3.5 cm. After 4 weeks, both pouches were mobilized further. However, the remaining gap did not allow primary anastomosis at that time, so the traction sutures were reconfigured and brought out externally through the skin above and below the incision. Daily increases in tension resulted in the ends virtually touching within 10 days. Now a contrast study showed the two lumens within 5 mm of each other, and primary anastomosis was completed without difficulty. Postoperative diagnosed gastroesophageal reflux and anastomotic stricture were controlled by a Thal hemifundoplication and dilatations. In conclusion, staged esophageal lengthening may be considered for a primary repair of EA even in cases with ultralong gap and TEF. PMID:18558163

Till, Holger; Muensterer, Oliver J; Rolle, Udo; Foker, John

2008-06-01

253

Should We Use Preoperative Epoetin-? in the Mildly Anemic Patient Undergoing Simultaneous Total Knee Arthroplasty?  

PubMed Central

Simultaneous knee arthroplasty is associated with significant blood loss. To prevent transfusion, three preoperative doses of epoetin-? were offered to mildly anemic simultaneous knee arthroplasty patients. A retrospective review, using ICD-9 codes, identified twenty patients from 2007-2009. Epoetin-? increased hemoglobin levels preoperatively (12.6 to 13.9, p<0.01). Twenty patients who did not receive epoetin-? were matched to study patients. Study patients were transfused less (55% vs 95%, p=0.012) and had similar inpatient length of stay. The average blood loss without transfusion was 4.6g/dL. The mildly anemic patient is at high-risk for packed red cell transfusion during simultaneous knee arthroplasty. Three preoperative doses of epoetin-? in the mildly anemic patient decreased total transfusions; however, it did not affect inpatient length of stay. PMID:23526659

Delasotta, Lawrence A; Orozco, Fabio; Jafari, S. Mehdi; Blair, Jamie L; Ong, Alvin

2013-01-01

254

Joint registries as continuous surveillance systems: the experience of the Catalan Arthroplasty Register (RACat).  

PubMed

The aim was to present results on prosthesis performance in Catalonia for the period 2005-2010. All publicly funded hospitals submit in an electronic format data on hip and knee arthroplasties: patients' insurance identification number, hospital, joint (hip/knee), type of arthroplasty (primary/revision), side (right/left), date of surgery and prosthesis (manufacturer name and catalogue number). A standard survival analysis based on Kaplan-Meier estimation was carried out. Fifty-two hospitals have sent information to the RACat which has data on 36,951 knee and 26,477 hip arthroplasties. Cumulative prostheses revision risks at 3 years were 3.3% (95% CI: 3.1-3.6) for knee, 2.9% (95% CI: 2.5-3.3) for total hip and 2.5% (95% CI: 2.0-3.1) for partial hip. When compared to other registries a higher risk of revision was observed. PMID:24054907

Allepuz, Alejandro; Martínez, Olga; Tebé, Cristian; Nardi, Joan; Portabella, Frederic; Espallargues, Mireia

2014-03-01

255

Comparison of arthroplasty trial publications after registration in ClinicalTrials.gov.  

PubMed

In 2005, the International Committee of Medical Journal Editors established a mandatory trial registration before study enrollment for publication in member journals. Our primary objective was to evaluate the publication rates of arthroplasty trials registered with ClinicalTrials.gov (CTG). We further aimed to examine the consistency of registration summaries with that of final publications. We searched CTG for all trials related to joint arthroplasty and conducted a thorough search for publications resulting from registered closed trials. Of 101 closed and completed trials, we found 23 publications, for an overall publication rate of 22.8%. Registration of arthroplasty trials in CTG does not consistently result in publication or disclosure of results. In addition, changes are frequently made to the final presentation of the data that are not reflected in the trial registry. PMID:22226609

Smith, Holly N; Bhandari, Mohit; Mahomed, Nizar N; Jan, Meryam; Gandhi, Rajiv

2012-08-01

256

Posterior single-incision approach to minimally invasive total hip arthroplasty  

PubMed Central

Enhanced surgical techniques and instrumentation enable surgeons to perform total hip arthroplasties through minimally invasive approaches. Using incisions typically less than 10 cm in length, surgeons can achieve adequate visualization of the surgical site while minimizing trauma to deep soft tissues. Associated reductions in morbidity should allow for improved rehabilitation and recovery. Although these techniques have been met with some controversy, a number of recent studies appear to attest to their safety and efficacy. Many of these studies have concentrated on a posterior single-incision technique for total hip arthroplasty. Favorable results for such outcomes as operative times, complication rates, pain, functional recovery, and blood loss have been reported, and patient satisfaction has been high. If surgeons and their patients are to achieve maximum benefit from minimally invasive total hip arthroplasties, it will be necessary to design effective educational tools that address the learning curve associated with these approaches. PMID:17653544

2007-01-01

257

Accuracy of haptic assessment of patellar symmetry in total knee arthroplasty.  

PubMed

Resection resulting in asymmetrically thick patellar arthroplasty in knee arthroplasty may lead to increased compression forces, wear, fracture, or loss of quadriceps power. Assessing the cut patella between the thumb and forefinger (haptic assessment) represents a convenient way to recognize asymmetry. In 2 test series, 8 orthopedic surgeons evaluated 24 precut solid foam patellae of varying asymmetric thickness by feeling the patella between thumb and forefinger, without visualization. Of 384 responses, in 73.2% asymmetry was underestimated, 10.4% assessments were exact, and in 16.4% asymmetry was overestimated. Specifically, 35.9% were correct within 1 mm, 60.7% within 2 mm, 81% within 3 mm, and 91.4% within 4 mm. The thickest half of the patella was correctly identified in 90.6% of responses. Haptic assessment of patellar symmetry is a useful technique in knee arthroplasty. PMID:15284985

DeOrio, James K; Peden, John P

2004-08-01

258

Long-term survival of semi-constrained total knee arthroplasty for revision surgery.  

PubMed

Semi-constrained implants provide stability in the setting of soft-tissue deficiency in revision total knee arthroplasty (TKA). This study evaluated our institution's long-term survival results with a semi-constrained implant used in the revision TKA setting. 234 semi-constrained revision total knee arthroplasties were performed in 209 patients. The average follow-up was 9 years. Forty repeat revisions were performed. 5-year survival was 91% and 10-year survival was 81%. Male gender significantly increased the risk of revision. At 10 years the average range of motion, pain level, and Knee Society score improved significantly (P < 0.001). Ninety percent of patients reported an improvement in their knee. The semi-constrained implant used in revision knee arthroplasty has acceptable implant survival and functional outcomes in the long-term follow-up period. PMID:24393376

Wilke, Benjamin K; Wagner, Eric R; Trousdale, Robert T

2014-05-01

259

Piriformis muscle rupture during total hip arthroplasty using a muscle-preserving posterior approach.  

PubMed

Total hip arthroplasty via muscle-sparing approaches is advocated and performed with increasing frequency. However, performing total hip arthroplasty through muscle-sparing approaches may require a more forceful retraction, which in turn may damage the muscles which the less invasive approach intended to preserve. We report on the rupture of the piriformis muscle during primary total hip replacement performed through a posterior approach intended to preserve this muscle. The prevalence and effects of such iatrogenic injuries are currently unknown, although unrecognised muscle damage may be a potential reason why early postoperative gait analyses could not demonstrate the expected benefits of less invasive surgery. Surgeons should be aware of this potential complication when performing total hip arthroplasty through a less invasive posterior approach. PMID:24563964

Solomon, Lucian B; Naal, Florian D; Howie, Donald W

2013-12-01

260

Prevalence and risk factors of thromboembolism after joint arthroplasty without chemical thromboprophylaxis in an Asian population.  

PubMed

Venous thromboembolism (VTE) is a serious complication after major orthopedic surgery. This study examined the prevalence and risk factors of VTE in patients undergoing arthroplasty without thromboprophylaxis. A total of 1608 patients who underwent elective knee or hip arthroplasty between 1996 and 2009 were evaluated. The incidence of VTE was 1.99% (n = 32). Of them, 0.24% (n = 4) were diagnosed with a pulmonary embolism. The risk factors associated with VTE were female sex, revision surgery, bilateral simultaneous procedure, CVA (cerebrovascular accident; thromboembolic stroke) history, and preoperative platelet count (all P > .05). There was an annual increase in the prevalence of VTE from 1996 to 2009 (P = .002). According to these results, thromboprophylaxis is strongly recommended in high-risk groups of Korean arthroplasty patients. PMID:21256698

Won, Man-Hee; Lee, Gye-Wang; Lee, Tong-Joo; Moon, Kyoung-Ho

2011-10-01

261

Gap Domain Wall Fermions  

E-print Network

I demonstrate that the chiral properties of Domain Wall Fermions (DWF) in the large to intermediate lattice spacing regime of QCD, 1 to 2 GeV, are significantly improved by adding to the action two standard Wilson fermions with supercritical mass equal to the negative DWF five dimensional mass. Using quenched DWF simulations I show that the eigenvalue spectrum of the transfer matrix Hamiltonian develops a substantial gap and that the residual mass decreases appreciatively. Furthermore, I confirm that topology changing remains active and that the hadron spectrum of the added Wilson fermions is above the lattice cutoff and therefore is irrelevant. I argue that this result should also hold for dynamical DWF and furthermore that it should improve the chiral properties of related fermion methods.

Pavlos M. Vranas

2006-06-22

262

Effort Gap Database  

NSDL National Science Digital Library

Maintained by the Biological Resources Research Center (BRRC) at the University of Nevada, Reno, the Effort Gap Database organizes information on biological research efforts in the Great Basin. Users may search the database (by multiple topics) for current and past projects, or they may add new information to the database. Typical returns provide information such as project title, scientific goals, available data, Principal Investigators, temporal and spatial scale of research, habitats in study area, types of organisms, source of funding, and finished products. Designed as an interactive Web application to allow and encourage researchers to share research foci and learn about other conservation biology projects in Nevada, this database is an excellent example of how to facilitate collaboration across multiple ecological scales and agencies.

263

Filling the launch gap  

NASA Astrophysics Data System (ADS)

Vehicles proposed to fill the gap in the U.S. space program's space transport needs for the next decade resulting from the January Challenger disaster, are discussed. Prior to the accident, the Air Force planned to purchase a Complementary Expendable Launch Vehicle system consisting of 10 single-use Titan-34D7 rockets. Another heavy lift booster now considered is the Phoenix H. Commercial launch vehicle systems projected to be available in the necessary time frame include the 215,000-pound thrust 4000-pound LEO payload capacity NASA Delta, the 11,300-pound LEO payload capacity Atlas Centaur the first ICBM, and the all-solid propellant expendable 2000-pound LEO payload Conestoga rocket. Also considered is the man-rated fully reusable Phoenix vertical take-off and vertical-landing launch vehicle.

Hoeser, S.

1986-05-01

264

Effect of anterior translation of the talus on outcomes of three-component total ankle arthroplasty  

PubMed Central

Background Ankle osteoarthritis commonly involves sagittal malalignment with anterior translation of the talus relative to the tibia. Total ankle arthroplasty has become an increasingly popular treatment for patients with symptomatic ankle osteoarthritis. However, no comprehensive study has been conducted on the outcomes of total ankle arthroplasty for osteoarthritis with preoperative sagittal malalignment. The purpose of this study was to evaluate the effect of anterior translation of the talus on outcomes of three-component total ankle arthroplasty. Methods One hundred and four osteoarthritic ankles in 104 patients who underwent three-component total ankle arthroplasty were included in this study. The 104 ankles were divided into 2 groups: ankles with anteriorly translated talus (50 ankles), and ankles with non-translated talus (54 ankles). Clinical and radiographic outcomes were assessed in both groups. The mean follow-up duration was 42.8?±?17.9 months (range, 24 to 95 months). Results Forty-six (92%) of 50 ankles with anterior translation of the talus showed relocation of the talus within the mortise at 6 months, and 48 (96%) ankles were relocated at 12 months after total ankle arthroplasty. But, 2 (4%) ankles were not relocated until the final follow-up. The AOFAS scores, ankle range of motion, and radiographic outcomes showed no significant difference between the two groups at the final follow-up (p?>?0.05 for each). Conclusions In majority of cases, the anteriorly translated talus in osteoarthritic ankles was restored to an anatomical position within 6 months after successful three-component total ankle arthroplasty. The clinical and radiographic outcomes in the osteoarthritic ankles with anteriorly translated talus group were comparable with those in non-translated talus group. PMID:24007555

2013-01-01

265

Baseline bone mineral density and bone turnover in pre-operative hip and knee arthroplasty patients  

PubMed Central

Aims Osteoporosis and abnormal bone metabolism may prove to be significant factors influencing the outcome of arthroplasty surgery, predisposing to complications of aseptic loosening and peri-prosthetic fracture. We aimed to investigate baseline bone mineral density (BMD) and bone turnover in patients about to undergo arthroplasty of the hip and knee. Methods We prospectively measured bone mineral density of the hip and lumbar spine using dual-energy X-ray absorptiometry (DEXA) scans in a cohort of 194 patients awaiting hip or knee arthroplasty. We also assessed bone turnover using urinary deoxypyridinoline (DPD), a type I collagen crosslink, normalised to creatinine. Results The prevalence of DEXA proven hip osteoporosis (T-score ? -2.5) among hip and knee arthroplasty patients was found to be low at 2.8% (4 of 143). Spinal osteoporosis prevalence was higher at 6.9% (12 of 175). Sixty patients (42% (60 of 143)) had osteopenia or osteoporosis of either the hip or spine. The mean T-score for the hip was -0.34 (sd 1.23), which is within normal limits, and the mean hip Z-score was positive at 0.87 (sd 1.17), signifying higher-than-average BMD for age. The median urinary DPD/creatinine was raised in both female patients at 8.1 (interquartile range (IQR) 6.6 to 9.9) and male patients at 6.2 (IQR 4.8 to 7.5). Conclusions Our results indicate hip and knee arthroplasty patients have higher BMD of the hip and spine compared with an age-matched general population, and a lower prevalence of osteoporosis. However, untreated osteoporotic patients are undergoing arthroplasty, which may negatively impact their outcome. Raised DPD levels suggest abnormal bone turnover, requiring further investigation. Cite this article: Bone Joint Res 2014;3:14–19. PMID:24443424

James, S. J.; Mirza, S. B.; Culliford, D. J.; Taylor, P. A.; Carr, A. J.; Arden, N. K.

2014-01-01

266

Successful LCL reconstruction and PCL repair for LCL tear and PCL avulsion following total knee arthroplasty.  

PubMed

Total knee arthroplasty represents a well-established and successful procedure; however, ligament incompetence is known to negatively affect surgical outcomes. Here we present an unusual case of early total knee arthroplasty failure secondary to femoral posterior cruciate ligament (PCL) avulsion and associated lateral collateral ligament (LCL) tear, treated successfully with primary PCL repair and LCL reconstruction. For LCL reconstruction, a peroneus longus allograft was passed through an anterior to posterior bony tunnel in the fibular head and docked into a horizontal femoral tunnel. Level of evidence Case report, Level IV. PMID:23756851

Flierl, Michael A; Bravman, Jonathan T; Eckhoff, Donald G

2014-11-01

267

Conversion of Fused Knee Following Distal Femur Tumor Surgery to Total Knee Arthroplasty  

PubMed Central

Conversion of knee arthrodesis to total knee arthroplasty is a difficult procedure accompanied by many complications due to soft tissue and extensor mechanism contracture and bone defects. We report two cases of distal femur osteosarcoma that had been undergone wide resection arthrodesis initially. Arthrodesis was converted to total knee arthroplasty with hinged prosthesis after many years. We describe patients' history and outline their surgical therapy and prognosis. To the best of the authors' knowledge, few cases have been previously reported in the literature. PMID:24616802

Jamshidi, Khodamorad; Hadi, Hoseinali; Ramezan Shirazi, Mehdi; Moslem, Alireza

2013-01-01

268

[Lower limb paresis after total hip arthroplasty. A rare differential diagnosis].  

PubMed

We report on a case of complex nerve damage during total hip arthroplasty. The most severe clinical symptom was proximal leg paresis with diffuse sensory loss. There was an extensive causal Iliopsoas hematoma which developed during the postoperative rehabilitation under therapeutic anticoagulation for atrial fibrillation. An iliopsoas hematoma with subsequent neurological deficits are rare events in the field of hip arthroplasty and a literature review is provided. The treatment of retroperitoneal hemorrhage is controversial but in most instances a conservative approach is favored. The prognosis of neurological damage is sobering as only 20?% of victims are expected to achieve complete restitution. PMID:23974464

Lachmann, M

2013-10-01

269

Flexor Carpi Ulnaris Muscle Flap for Soft Tissue Reconstruction after Total Elbow Arthroplasty  

PubMed Central

The soft tissue at the tip of the olecranon is very thin, leading to the frequent occurrence of wound complications after total elbow arthroplasty. To cover a soft tissue defect of the elbow, the flexor carpi ulnaris muscle flap is thought to be appropriate for reconstruction of the elbow with regard to its size, location, and blood supply. We got positive clinical results, so we report our experiences of using a flexor carpi ulnaris muscle flap for soft tissue reconstruction after total elbow arthroplasty.

Okamoto, Syunro; Ai, Hachinota; Tsuchiya, Hiroyuki

2014-01-01

270

Fat embolization and fatal cardiac arrest during hip arthroplasty with methylmethacrylate  

Microsoft Academic Search

Purpose  This case report describes a cardiac arrest during a cemented hip arthroplasty procedure. Hemodynamic instability during methylmethacrylate\\u000a use in arthroplasty surgery can be explained by fat embolization rather than the inherent toxicity of the monomer.\\u000a \\u000a \\u000a \\u000a Clinical features  A 78-yr-old woman required a cemented hemiarthroplasty for a pathologic left subcapital fracture. The patient’s past medical\\u000a history included stable angina, diet-controlled type II

Katherine M. Fallon; John G. Fuller; Patricia Morley-Forster

2001-01-01

271

Two-stage Exchange Knee Arthroplasty: Does Resistance of the Infecting Organism Influence the Outcome?  

Microsoft Academic Search

Background  Periprosthetic joint infection after TKA is a challenging complication. Two-stage exchange arthroplasty is the accepted standard\\u000a of care, but reported failure rates are increasing. It has been suggested this is due to the increased prevalence of methicillin-resistant\\u000a infections.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  We asked the following questions: (1) What is the reinfection rate after two-stage exchange arthroplasty? (2) Which risk factors\\u000a predict failure? (3)

Mark F. Kurd; Elie Ghanem; Jill Steinbrecher; Javad Parvizi

2010-01-01

272

Revision patellofemoral arthroplasty: three- to seven-year follow-up.  

PubMed

In this series, a failed first-generation patellofemoral arthroplasty was revised to a second-generation prosthesis. Fourteen knees were prospectively followed up for a mean of 60 months. Primary procedure failure was due to component malposition, subluxation, polyethylene wear, or overstuffing. Mean Bristol knee scores improved from 58 (range, 36-86) to 79 (range, 38-100) (P < .001). Mild femorotibial arthritis (Ahlbach stage I) was present in 5 knees and predicted a poorer outcome. At most recent follow-up, there was no evidence of wear, loosening, or subluxation. Significant improvement can be obtained when revising the failed patellofemoral arthroplasty, provided there is no femorotibial arthritis. PMID:18534464

Hendrix, Michiel R G; Ackroyd, Christopher E; Lonner, Jess H

2008-10-01

273

Indium-111 leucocyte scanning in the evaluation of painful hip arthroplasty.  

PubMed

Thirty patients with a painful hip arthroplasty had an In-111 leucocyte scan before surgical reexploration. In 12 patients, the In-111 leucocyte scan was abnormal and in all of them, microorganisms were found at the culture of the material from their hips at the operation. Among the 18 patients with a normal scan no infection was found in 17. In one patient, a thick-walled abscess growing Escherichia coli was found. We conclude that In-111 scanning is sensitive, specific and therefore useful in the differential diagnosis of pain after hip arthroplasty. PMID:6670484

Mulamba, L; Ferrant, A; Leners, N; de Nayer, P; Rombouts, J J; Vincent, A

1983-10-01

274

Avulsion fracture of the ischium following complex total hip arthroplasty: an unusual cause of hip pain.  

PubMed

Total hip arthroplasty in the high riding dislocated hip is a technically difficult undertaking, with major reconstruction required on both the acetabular and femoral sides. With reconstruction at a near-anatomic hip center, reduction of the arthroplasty is difficult because of the long-standing limb shortening. The major block to reduction is tension of the soft tissues, particularly the hamstrings. We report a case of ischial tuberosity avulsion fracture following such a complex reconstruction despite femoral shortening subtrochanteric osteotomy. This illustrates the importance of the hamstring group in maintaining the dislocation and emphasizes the need to prevent overtension of the soft tissues in such complex reconstructive procedures. PMID:9726330

Smith, P N; Gie, G A

1998-08-01

275

Gap and stripline combined monitor  

DOEpatents

A combined gap and stripline monitor device for measuring the intensity and position of a charged particle beam bunch in a beam pipe of a synchrotron radiation facility is disclosed. The monitor has first and second beam pipe portions with an axial gap therebetween. An outer pipe cooperates with the first beam pipe portion to form a gap enclosure, while inner strips cooperate with the first beam pipe portion to form a stripline monitor, with the stripline length being the same as the gap enclosure length. 4 figs.

Yin, Y.

1986-08-19

276

Gap and stripline combined monitor  

DOEpatents

A combined gap and stripline monitor device for measuring the intensity and position of a charged particle beam bunch in a beam pipe of a synchrotron radiation facility. The monitor has first and second beam pipe portions with an axial gap therebetween. An outer pipe cooperates with the first beam pipe portion to form a gap enclosure, while inner strips cooperate with the first beam pipe portion to form a stripline monitor, with the stripline length being the same as the gap enclosure length.

Yin, Y.

1984-02-16

277

Gap and stripline combined monitor  

DOEpatents

A combined gap and stripline monitor device (10) for measuring the intensity and position of a charged particle beam bunch in a beam pipe of a synchotron radiation facility. The monitor has first and second beam pipe portions (11a, 11b) with an axial gap (12) therebetween. An outer pipe (14) cooperates with the first beam pipe portion (11a) to form a gap enclosure, while inner strips (23a-d) cooperate with the first beam pipe portion (11a) to form a stripline monitor, with the stripline length being the same as the gap enclosure length.

Yin, Yan (Palo Alto, CA)

1986-01-01

278

One gap, two gaps, and universality in high temperature superconductors  

NASA Astrophysics Data System (ADS)

A dramatic change in energy gap anisotropy upon reducing carrier concentration has often been observed in the cuprate high temperature superconductors (HTSC). A simple d-wave gap in materials with the optimal Tc evolves with underdoping into a ?two-gap? structure, with different dependences in different regions of momentum space. It is tempting to associate the large antinodal gap with a second order parameter distinct from d-wave superconductivity. We use angle-resolved photoemission spectroscopy (ARPES) to show that this two-gap behavior, and the concomitant destruction of well defined electronic excitations, are not universal features of HTSC, and depend sensitively on how the underdoped materials are prepared. Depending on cation substitution, underdoped crystals either show two-gap behavior or not. In contrast, many characteristics of HTSC like the superconducting dome (Tc versus doping), nodal quasiparticles, antinodal gap that decreases monotonically with doping, and the pseudogap, are present in all samples, irrespective of whether they exhibit two-gap behavior or not. Our results imply that universal aspects of high Tc superconductivity are insensitive to differences in the electronic states in the antinodal region of the Brillouin zone.

Zhao, Junjing; Chatterjee, Utpal; Norman, Mike; Randeria, Mohit; Campuzano, Juan Carlos

2012-02-01

279

fastGapFill: efficient gap filling in metabolic networks  

PubMed Central

Motivation: Genome-scale metabolic reconstructions summarize current knowledge about a target organism in a structured manner and as such highlight missing information. Such gaps can be filled algorithmically. Scalability limitations of available algorithms for gap filling hinder their application to compartmentalized reconstructions. Results: We present fastGapFill, a computationally efficient tractable extension to the COBRA toolbox that permits the identification of candidate missing knowledge from a universal biochemical reaction database (e.g. Kyoto Encyclopedia of Genes and Genomes) for a given (compartmentalized) metabolic reconstruction. The stoichiometric consistency of the universal reaction database and of the metabolic reconstruction can be tested for permitting the computation of biologically more relevant solutions. We demonstrate the efficiency and scalability of fastGapFill on a range of metabolic reconstructions. Availability and implementation: fastGapFill is freely available from http://thielelab.eu. Contact: ines.thiele@uni.lu Supplementary information: Supplementary data are available at Bioinformatics online. PMID:24812336

Thiele, Ines; Vlassis, Nikos; Fleming, Ronan M. T.

2014-01-01

280

Fatal intrahepatic hemorrhage after nadroparin use for total hip arthroplasty.  

PubMed

Low-molecular-weight heparins have become the predominant choice for deep venous thrombosis prophylaxis and treatment. However, their use may cause bleeding complications. Intrahepatic bleeding is exceptional and only very few cases have been described. The authors present a unique case of fatal intrahepatic hematoma complicating nadroparin use in a 65-year-old woman with a hepatic cyst who was admitted to hospital for unilateral total hip arthroplasty. At autopsy, hemoperitoneum (2,000 ml of blood and clots) was evident. A ruptured sub-capsular hematoma involving the right lobe of the liver was observed. The hemorrhage within the cyst induced by the nadroparin use was likely responsible for the subsequent hepatic hematoma, liver rupture, and death. This case highlights the need for pathologists and surgeons to be aware of the possibility of intrahepatic hematoma in patients who have received low-molecular-weight heparins, undergone major surgery and present postoperative hemodynamic instability, especially in those with preoperative diagnosis of hepatic cyst. PMID:25108423

Ventura, Francesco; Bonsignore, Alessandro; De Stefano, Francesco; Pizzorno, Enrico; Palmiere, Cristian

2014-12-01

281

Preoperative Strength Training for Elderly Patients Awaiting Total Knee Arthroplasty  

PubMed Central

Objective. To investigate the feasibility and effects of additional preoperative high intensity strength training for patients awaiting total knee arthroplasty (TKA). Design. Clinical controlled trial. Patients. Twenty-two patients awaiting TKA. Methods. Patients were allocated to a standard training group or a group receiving standard training with additional progressive strength training for 6?weeks. Isometric knee extensor strength, voluntary activation, chair stand, 6-minute walk test (6MWT), and stair climbing were assessed before and after 6?weeks of training and 6 and 12?weeks after TKA. Results. For 3 of the 11?patients in the intensive strength group, training load had to be adjusted because of pain. For both groups combined, improvements in chair stand and 6MWT were observed before surgery, but intensive strength training was not more effective than standard training. Voluntary activation did not change before and after surgery, and postoperative recovery was not different between groups (P > 0.05). Knee extensor strength of the affected leg before surgery was significantly associated with 6-minute walk (r = 0.50) and the stair climb (r ? = 0.58, P < 0.05). Conclusion. Intensive strength training was feasible for the majority of patients, but there were no indications that it is more effective than standard training to increase preoperative physical performance. This trial was registered with NTR2278. PMID:24693435

van Leeuwen, D. M.; de Ruiter, C. J.; Nolte, P. A.; de Haan, A.

2014-01-01

282

Analysis of Femoral Components of Cemented Total Hip- Arthroplasty  

E-print Network

In cemented Total Hip Arthroplasty (THA), material chosen for femoral stem and cross section of stem itself, proved to be critical parameters for, stress distribution in the femoral components, interfacial stresses and micro movements. Titanium alloy (Ti6Al4V), when used as a material for femoral stem, recorded large displacement as compared to Chromium alloy (CoCrMo) stems. This large displacement in case of Ti6Al4V caused the stem to bend inside the cement mantle, thus destroying it. Thus, CoCrMo proved to be a better in cemented THA. Failure in THA may occur at cement-stem or cement-bone interface, thus interfacial stresses and micro movements were analysed in the present study. Comparison between trapezium and circular cross section showed that, femoral stem with trapezium cross section underwent lesser amount of sliding and debonding, at both interfaces, as compared to circular cross section. Moreover, trapezium cross section also generated lower peak stresses in femoral stem and cortical femur. The pres...

Singh, Shantanu

2014-01-01

283

Testing of silicon nitride ceramic bearings for total hip arthroplasty.  

PubMed

Modern ceramic bearings used in total hip arthroplasty (THA) consist of a femoral head (ball) articulating inside a hemispherical acetabular cup (socket); the ball and socket are made of alumina (Al(2)O(3)) and Al(2)O(3)-based composite materials. In the present study, total hip bearings were made from a different ceramic material, silicon nitride (Si(3)N(4)), by sintering and hot isostatic pressing of powders. The resulting material had improved mechanical properties over modern Al(2)O(3) THA bearings, with a flexural strength of 920 +/- 70 MPa, a Weibull modulus of 19, and a fracture toughness of 10 +/- 1 MPa m(1/2). Unlike zirconia-based ceramics that have also been used in THA, accelerated aging of Si(3)N(4) did not adversely affect the flexural strength. In simulated wear tests, Si(3)N(4) acetabular cups produced low-volumetric wear whether articulating against Si(3)N(4) or cobalt-chromium (CoCr) femoral heads. The results of this investigation suggest that Si(3)N(4) may allow improved THA bearings that combine the reliability of metal femoral heads with the low wear advantages of ceramic materials. PMID:18491410

Bal, B Sonny; Khandkar, Ashok; Lakshminarayanan, R; Clarke, Ian; Hoffman, Aaron A; Rahaman, Mohamed N

2008-11-01

284

Indoor and Outdoor Mobility following Total Knee Arthroplasty  

PubMed Central

ABSTRACT Purpose: To determine the relationship between indoor and outdoor mobility capacity in older adults with unilateral total knee arthroplasty (TKA) and, secondarily, to determine walking intensity in the same population and to compare all outcomes to a control group of older adults without knee pathology. Method: In this cross-sectional study, participants (TKA=16, mean 22.9 (SD 9.7) mo post TKA; control=22) completed indoor walking tests and a 580 m outdoor course that included varying terrain (e.g., curbs, grass, sidewalk) and frequent changes in direction. Walking capacity was assessed using stopwatches, global positioning system watches and accelerometers. Results: Outdoor walking time was moderately correlated (p<0.05) with the timed up-and-go (TUG) test (r=0.65), stair-climb test (SCT) (r=0.67 ascending, r=0.79 descending), 10 m walk test (10 mWT) (r=0.73), and 6-minute walk test (6 MWT) (r=?0.75). Based on activity counts, walking intensity levels for participants in both groups were moderate (outdoor walk and 6 MWT). There was no significant difference in walking capacity between groups (TUG, SCT, 10 mWT, 6 MWT, outdoor walk). Conclusions: Common clinical walking tests are moderately correlated with outdoor mobility. Mobility capacity of individuals post TKA was similar to controls in both indoor and outdoor environments, and participants in both groups achieved moderate physical activity levels with walking. PMID:24403699

Storey, Ava S.T.; Myrah, Ainslie M.; Bauck, Robyn A.; Brinkman, Danielle M.; Friess, Shawn N.

2013-01-01

285

Clinical outcomes assessment of three similar hip arthroplasty bearing surfaces.  

PubMed

This report examines the clinical performance of three very similar total hip arthroplasty designs with distinctly different bearing surfaces used over the course 10-17 years. Clinical outcomes assessments for each group are compared in the context of varying implant related costs related to the latest technology at the time of surgery. Eighty-one surgeries were studied and differ by bearing surface. In this study, 36 hips are ceramic on polyethylene, 27 are metal on polyethylene and 18 are metal on metal. All polyethylene components are nonhighly cross-linked. The ceramic on polyethylene group has younger patients, on average, and higher percentage of patients with significant polyethylene wear. These groups have an average follow-up time of 8.6 years when assessing functional hip scores, thigh pain, groin pain, revision surgeries and radiographic osteolysis. The implant purchasing cost at the time of surgery was assessed to determine if a correlation exists between outcomes and the more technologically advanced implants use at the time of surgery. Based on midterm clinical outcome assessment, no correlation between initial hospital cost and clinical outcomes of one bearing surface over another can be found. PMID:25002938

Parsons, Christopher; Batson, Ryan; Reighard, Shane; Tanner, Stephanie; Snider, Becky; Pace, Thomas B

2014-04-22

286

Polyethylene Oxidation in Total Hip Arthroplasty: Evolution and New Advances  

PubMed Central

Ultra-high molecular weight polyethylene (UHMWPE) remains the gold standard acetabular bearing material for hip arthroplasty. Its successful performance has shown consistent results and survivorship in total hip replacement (THR) above 85% after 15 years, with different patients, surgeons, or designs. As THR results have been challenged by wear, oxidation, and liner fracture, relevant research on the material properties in the past decade has led to the development and clinical introduction of highly crosslinked polyethylenes (HXLPE). More stress on the bearing (more active, overweighted, younger patients), and more variability in the implantation technique in different small and large Hospitals may further compromise the clinical performance for many patients. The long-term in vivo performance of these materials remains to be proven. Clinical and retrieval studies after more than 5 years of in vivo use with HXLPE in THR are reviewed and consistently show a substantial decrease in wear rate. Moreover, a second generation of improved polyethylenes is backed by in vitro data and awaits more clinical experience to confirm the experimental improvements. Also, new antioxidant, free radical scavengers, candidates and the reinforcement of polyethylene through composites are currently under basic research. Oxidation of polyethylene is today significantly reduced by present formulations, and this forgiving, affordable, and wellknown material is still reliable to meet today’s higher requirements in total hip replacement. PMID:20111694

Gomez-Barrena, Enrique; Medel, Francisco; Puertolas, Jose Antonio

2009-01-01

287

Multilobulated popliteal cyst after a failed total knee arthroplasty.  

PubMed

Popliteal cyst is a rare finding after total knee arthroplasty (TKA), but when present, it might indicate a malfunction of the TKA related to generation of wear-particles, or loosening. We present a case of a multilobulated popliteal cyst developing in a patient 8 years after primary TKA. The cyst was associated with a mechanical prosthetic loosening. The primary complaint of the patient was pain in the posterior region of the knee. A two-stage procedure consisting of cyst excision at first, followed after 5 months by a revision TKA was performed. Intraoperatively, a darkish, multilobulated cyst with a well-defined thick wall filled with fluid containing polyethylene debris, communicating with the knee joint was found. After 3 years of follow-up, the patient was satisfied and walked without the support of a cane. The patient presented a satisfactory knee range of motion. Clinical, radiological and ultrasound investigations ruled out popliteal cyst recurrence. A dissecting popliteal cyst associated with a failed TKA should be excised because it contains polyethylene debris that constitutes an induced factor for prosthetic loosening. A two-stage procedure with quite a long time in-between, as presented in this paper, can be a useful alternative to manage such a problem, in particular in very old patients associated with other medical problems. PMID:16897071

Moretti, Biagio; Patella, Vittorio; Mouhsine, Elyazid; Pesce, Vito; Spinarelli, Antonio; Garofalo, Raffaele

2007-02-01

288

How to address the patella in revision total knee arthroplasty.  

PubMed

Patellar issues need to be carefully addressed during any revision TKA and the surgeon often faces the question of what to do with the patella at the time of revision. The choice of treatment is often made by balancing what is technically feasible with the risk of potential complications and takes into account the reason for the revision, the type of implant (i.e., metal-backing or all-polyethylene), the duration of implantation, the fixation, the stability, the sterilization technique, the wear, the presence of osteolysis, the compatibility with the femoral component, and most importantly the remaining bone stock. The various treatment options then include retention of the patellar component, revision of the patellar component, removal of the component with retention of the patellar bony shell (patelloplasty or resection arthroplasty), excision of the patella (partial or total patellectomy), secondary resurfacing, and reconstruction/augmentation of the patellar bone stock. Isolated patellar revision is associated with a high complication rate and recurrent failure when poor patellar tracking, incongruent designs and malalignment of the femoral and tibial components exist. Retention of a well-fixed all-PE (non-oxidized) patella is advocated where possible and revision of metal-backed patella is recommended (unless well fixed with poor bone stock). In the situation of a deficient patella, patelloplasty, augmentation procedures and very rarely patellectomy are other viable options. PMID:18819807

Maheshwari, Aditya V; Tsailas, Panagiotis G; Ranawat, Amar S; Ranawat, Chitranjan S

2009-03-01

289

Total knee arthroplasty using cruciate-retaining kinematic condylar prosthesis.  

PubMed

The purpose of the current study was to evaluate the long-term results of the Kinematic I condylar prosthesis with retention of the posterior cruciate ligament. One hundred sixty-eight total knee arthroplasties in 118 patients (mean age, 65.2 years; range, 21-88 years) were inserted with cement, an all-polyethylene patella, metal-backed tibia, and posterior cruciate ligament retention. Sixty-one patients (86 knees) died, one patient had an above-knee amputation, and three patients (five knees) were lost to followup; therefore, 66 knees (excluding revisions) in 50 patients were available for followup at a mean of 15.7 +/- 1.1 years (range, 14-20 years). Of the entire cohort of 168 knees, 13 have been revised: one for medial femoral condyle fracture, one for tibiofemoral instability, one for femoral and two for tibial component aseptic loosening, four for tibial polyethylene wear, and four for patellar component aseptic loosening. The 15-year survivorship free of any component revision excluding infections was 88.7% (confidence interval, 82%-95%). The 15-year survivorship free of radiographic loosening and/or revision of any component was 85.1% (confidence interval, 78%-92%). The current study shows good function and survivorship of the posterior cruciate-sparing Kinematic I condylar prosthesis at a mean of 15.7 +/- 1.1 years. PMID:11451130

Sextro, G S; Berry, D J; Rand, J A

2001-07-01

290

Primary posterior stabilized total knee arthroplasty: analysis of different instrumentation  

PubMed Central

Background Intercondylar femoral bone removal during posterior stabilized (PS) total knee arthroplasty (TKA) makes many cruciate substituting implant designs less appealing than cruciate retaining implants. Bone stock conservation is considered fundamental in the prevision of future revision surgeries. The purpose of this study was to compare the quantity of intercondylar bone removable during PS housing preparation using three contemporary PS TKA instrumentations. Method We compared different box cutting jigs which were utilized for the PS housing of three popular PS knee prostheses. The bone removal area from every PS box cutting jig was three-dimensionally measured. Results Independently from the implant size, the cutting jig for a specific PS TKA always resected significantly less bone than the others: this difference was statistically significant, especially for small- to medium-sized total knee femoral components. Conclusion This study does not establish a clinical relevance of removing more or less bone at primary TKA, but suggests that if a PS design is indicated, it is preferable to select a model which possibly resects less distal femoral bone. PMID:25037275

2014-01-01

291

Overweight preoperatively impairs clinical outcome after knee arthroplasty  

PubMed Central

Background Obesity contributes much to the development of knee osteoarthritis. However, the association between obesity and outcome after knee replacement is controversial. We investigated whether there was an association between the preoperative body mass index (BMI) of patients who underwent total knee arthroplasty (TKA) and their quality of life (QoL) and physical function 3–5 years after surgery. Methods 197 patients who had undergone primary TKA participated in a 3–5 year follow-up study. The outcome measures were the patient-reported Short Form 36 (SF-36) and the American Knee Society score (KSS). Results Ordinal logistic regression analysis (adjusted for age, sex, disease, and surgical approach) revealed a statistically significant correlation between BMI and 9 of the 14 outcome measures. For all outcome measures, we found an odds ratio (OR) of < 1. A difference in BMI of 1 kg/m2 increased the risk of a lower score from a minimum of 2% (OR = 0.98 (0.93–1.03); p = 0.5) (Mental Component score) to a maximum of 13% (OR = 0.87 (0.82–0.93); p < 0.001) (KSS function score). Interpretation Our findings indicate that TKA patients’ preoperative BMI is a predictor of the clinical effect and patients’ quality of life 3–5 years postoperatively. A high BMI increases the risk of poor QoL (SF-36) and physical function (KSS). PMID:23992141

Lauersen, Jens Ole; S?balle, Kjeld; Mechlenburg, Inger

2013-01-01

292

Fixed or mobile-bearing total knee arthroplasty  

PubMed Central

Fixed and mobile-bearing in total knee arthroplasty are still discussed controversially. In this article, biomechanical and clinical aspects in both fixed and mobile-bearing designs were reviewed. In biomechanical aspect, the mobile-bearing design has proved to provide less tibiofemoral contact stresses under tibiofemoral malalignment conditions. It also provides less wear rate in in-vitro simulator test. Patients with posterior stabilized mobile-bearing knees had more axial tibiofemoral rotation than patients with posterior stabilized fixed-bearing knees during gait as well as in a deep knee-bend activity. However, in clinical aspect, the mid-term or long-term survivorship of mobile-bearing knees has no superiority over that of fixed-bearing knees. The theoretical advantages for mobile-bearing design to provide a long-term durability have not been demonstrated by any outcome studies. Finally, the fixed-bearing design with all-polyethylene tibial component is suggested for relatively inactive, elder people. The mobile-bearing design is suggested for younger or higher-demand patients due to the potential for reduced polyethylene wear and more normal kinematics response after joint replacement. For younger surgeon, the fixed-bearing design is suggested due to less demand for surgical technique. For experienced surgeon, one familiar surgical protocol and instrumentation is suggested rather than implant design, either fixed-bearing or mobile-bearing. PMID:17204165

Huang, Chun-Hsiung; Liau, Jiann-Jong; Cheng, Cheng-Kung

2007-01-01

293

Clinical Outcomes Assessment of Three Similar Hip Arthroplasty Bearing Surfaces  

PubMed Central

This report examines the clinical performance of three very similar total hip arthroplasty designs with distinctly different bearing surfaces used over the course 10-17 years. Clinical outcomes assessments for each group are compared in the context of varying implant related costs related to the latest technology at the time of surgery. Eighty-one surgeries were studied and differ by bearing surface. In this study, 36 hips are ceramic on polyethylene, 27 are metal on polyethylene and 18 are metal on metal. All polyethylene components are nonhighly cross-linked. The ceramic on polyethylene group has younger patients, on average, and higher percentage of patients with significant polyethylene wear. These groups have an average follow-up time of 8.6 years when assessing functional hip scores, thigh pain, groin pain, revision surgeries and radiographic osteolysis. The implant purchasing cost at the time of surgery was assessed to determine if a correlation exists between outcomes and the more technologically advanced implants use at the time of surgery. Based on midterm clinical outcome assessment, no correlation between initial hospital cost and clinical outcomes of one bearing surface over another can be found. PMID:25002938

Parsons, Christopher; Batson, Ryan; Reighard, Shane; Tanner, Stephanie; Snider, Becky; Pace, Thomas B.

2014-01-01

294

Patient-specific instrumentation in total knee arthroplasty.  

PubMed

Patient-specific instrumentation (PSI) is a technology that allows the surgeon to perform a total knee arthroplasty (TKA) potentially more easily with preformed cutting blocks and jigs, which are developed from preoperative computed tomographic or magnetic resonance image scans of the knee. It was introduced with the goal of reducing surgical time, minimizing costs, improving alignment, and reducing radiographic outliers when performing a TKA. Although multiple reports have demonstrated that PSI can reduce the amount of trays and instrumentation required, operative time, and turnover rates, this has not been extrapolated to an overall cost reduction. This is potentially related to the costs of preoperative imaging and the intrinsic costs of production of the patient-specific guides. With the present technology, it is also controversial whether improvements in alignment can be achieved. In addition, it remains to be seen whether this will lead to a reduction in costs and improvements in clinical, radiographic, and functional outcomes. As PSI is relatively new, there is a paucity of long-term studies, which makes it difficult to predict whether long-term improvements in implant survivorship will lead to substantial improvements in patient function, overall outcomes, or cost benefits. PMID:24764234

Jauregui, Julio J; Cherian, Jeffrey J; Kapadia, Bhaveen H; Banerjee, Samik; Issa, Kimona; Harwin, Steven F; Mont, Michael A

2014-06-01

295

Comparison of Patient and Surgeon Expectations of Total Hip Arthroplasty  

PubMed Central

Objectives Analysis of discrepancies between patient and surgeon expectations before total hip arthroplasty (THA) should enable a better understanding of motives of dissatisfaction about surgery, but this question has been seldom studied. Our objectives were to compare surgeons' and patients' expectations before THA, and to study factors which affected surgeon-patient agreement. Methods 132 adults (mean age 62.8+/?13.7 years, 52% men) on waiting list for THA in three tertiary care centres and their 16 surgeons were interviewed to assess their expectations using the Hospital for Special Surgery Total Hip Replacement Expectations Survey (range 0–100). Patients' and surgeons' answers were compared, for the total score and for the score of each item. Univariate analyses tested the effect of patients' characteristics on surgeons' and patients' expectations separately, and on surgeon-patient differences. Results Surgeon and patient expectations' mean scores were high (respectively 90.9+/?11.1 and 90.0+/?11.6 over 100). Surgeons' and patients' expectations showed no systematic difference, but there was little agreement on Bland and Altman graph and correlation coefficient was low. Patients had higher expectations than surgeons for sports. Patients rated their expectations according to trust in physician and mental quality of life, surgeons considered disability. More disabled patients and patients from a low-income professional category were often “more optimistic” than their surgeons. Conclusion Surgeons and patients often do not agree on what to expect from THA. More disabled patients expect better outcomes than their surgeons. PMID:22272303

Jourdan, Claire; Poiraudeau, Serge; Descamps, Stephane; Nizard, Remy; Hamadouche, Moussa; Anract, Philippe; Boisgard, Stephane; Galvin, Myriam; Ravaud, Philippe

2012-01-01

296

Effects of increased surgical volume on total knee arthroplasty complications.  

PubMed

The effect of increased total knee arthroplasty (TKA) surgical volume on the incidence of knee complications within a single surgeon's practice was determined. Data were collected prospectively on 600 primary TKAs. Major complications required knee reoperation. Minor complications were wound concerns requiring increased surveillance or oral antibiotics. Twelve major (2.0%) and 40 minor (6.7%) complications occurred at minimum 2-year follow-up. Surgical volume increased from 57 to 150 procedures per 6 months through the course of the study. Multivariate analysis determined that increased surgical volume was associated with lower rates of both major and minor complications, adjusted odds ratio 0.62 (95% confidence interval [CI], 0.40-0.96) and 0.56 (95% CI, 0.43-0.73), respectively. For each additional 50 procedures performed within a 6-month interval, major complications were reduced by 38% (P = .03), and minor complications were reduced by 44% (P < .0001). All complications were significantly decreased when the surgeon was performing 112 +/- 44 TKAs compared with 85 +/- 49 TKAs per 6-month interval. PMID:18722304

Schroer, William C; Calvert, George T; Diesfeld, Paul J; Reedy, Mary E; LeMarr, Angela R

2008-09-01

297

Rotation flaps for coverage after total knee arthroplasty  

PubMed Central

OBJECTIVE: To evaluate the results obtained using local myocutaneous rotation flaps in cases of wound dehiscence after total knee arthroplasty. METHODS: Patients undergoing these surgical procedures were selected in the 2000-2012 period. The nine selected cases during this period were subjected to flap coverage due to skin dehiscence associated with infection. In eight cases we used rotation flaps of the medial gastrocnemius, and in one case we used advancing skin. RESULTS: Eighty nine percent of the cases were successful in the coverage of the prosthesis and the viability of the flaps. In four cases it was possible to maintain or review the prosthesis. Four other cases progressed to amputation due to failure on treatment of infections, and one case remained without the prosthesis. The functional evaluation showed an unsatisfactory outcome in 89% of cases. CONCLUSION: Coverage flaps are a good option for the treatment of cases of dehiscence with exposure of the prosthesis and the functional failure was associated with the inability to control the infection and the damage it caused. Level of Evidence IV, Case Series. PMID:24453672

Pozzobon, Leonardo Rafael; Helito, Camilo Partezani; Guimaraes, Tales Mollica; Gobbi, Riccardo Gomes; Pecora, Jose Ricardo; Camanho, Gilberto Luis

2013-01-01

298

Acute Infection in Total Knee Arthroplasty: Diagnosis and Treatment  

PubMed Central

Infection is one of the most serious complications after total knee arthroplasty (TKA). The current incidence of prosthetic knee infection is 1-3%, depending on the series. For treatment and control to be more cost effective, multidisciplinary groups made up of professionals from different specialities who can work together to eradicate these kinds of infections need to be assembled. About the microbiology, Staphylococcus aureus and coagulase-negative staphylococcus were among the most frequent microorganisms involved (74%). Anamnesis and clinical examination are of primary importance in order to determine whether the problem may point to a possible acute septic complication. The first diagnosis may then be supported by increased CRP and ESR levels. The surgical treatment for a chronic prosthetic knee infection has been perfectly defined and standardized, and consists in a two-stage implant revision process. In contrast, the treatment for acute prosthetic knee infection is currently under debate. Considering the different surgical techniques that already exist, surgical debridement with conservation of the prosthesis and polythene revision appears to be an attractive option for both surgeon and patient, as it is less aggressive than the two-stage revision process and has lower initial costs. The different results obtained from this technique, along with prognosis factors and conclusions to keep in mind when it is indicated for an acute prosthetic infection, whether post-operative or haematogenous, will be analysed by the authors. PMID:23919094

Martinez-Pastor, Juan Carlos; Macule-Beneyto, Francisco; Suso-Vergara, Santiago

2013-01-01

299

The "banana peel" exposure method in revision total knee arthroplasty.  

PubMed

We present an exposure technique, the "banana peel," that has been used exclusively for revision total knee arthroplasty (TKA) for more than 20 years. We retrospectively reviewed use of this technique in 102 consecutive patients (mean age, 62 years; range, 41-92 years) who underwent tibial-femoral stemmed revision TKA. There were 5 deaths, leaving 97 patients (98 knees) for the study. The technique involves peeling the patella tendon as a sleeve off the tibia, leaving the extensor mechanism intact with a lateral hinge of soft tissue. A quadriceps "snip" is also done proximally. Patients with a minimum follow-up of 24 months were included. Telephone interviews and chart reviews were conducted, and Knee Society scores were obtained. Mean follow-up was 39 months (range, 24-56 months). No patient reported disruption of the extensor mechanism or decreased ability to extend the operative knee. Mean Knee Society score was 176 (range, 95-200). Mean postoperative motion was 106 degrees. No patient reported pain over the tibial tubercle. The banana-peel technique for exposing the knee during revision TKA is a safe method that can be used along with a proximal quadriceps snip and does not violate the extensor mechanism, maintaining continuity of the knee extensors. PMID:18033563

Lahav, Amit; Hofmann, Aaron A

2007-10-01

300

Femoral neck resorption following hybrid metal-on-metal hip resurfacing arthroplasty: a radiological and biomechanical analysis  

Microsoft Academic Search

Introduction  With the resurgence of resurfacing hip arthroplasty complications such as femoral neck fracture and thinning have been identified.\\u000a We therefore conducted a radiological and biomechanical evaluation of factors affecting femoral neck resorption following\\u000a resurfacing hip arthroplasty (RHA).\\u000a \\u000a \\u000a \\u000a \\u000a Methods  We retrospectively reviewed 61 resurfacing hip arthroplasties in 53 patients with a minimum of a 2-year follow-up. Data regarding\\u000a age, gender, body mass

Jibu Joseph; Michael Mullen; Andrew McAuley; Anand Pillai

2010-01-01

301

Popliteal pseudoaneurysm after total knee arthroplasty secondary to intraoperative arterial injury with a surgical pin: review of the literature.  

PubMed

Pseudoaneurysms of the popliteal artery after total knee arthroplasty are rare. Although many possible explanations are proposed in the literature, no intimate mechanism of injury to the artery is previously described. We report on a case of popliteal pseudoaneurysm after a total knee arthroplasty that presented clinically on the second postoperative day. Open vascular surgery with resection of the pseudoaneurysm and end-to-end bypass of contralateral saphena vein graft was successfully performed. At the time of the surgery, a hole was clearly identified on the anterior wall of the popliteal artery due to a perforation with a pin used during the knee arthroplasty. The patient had no further complications. PMID:18534483

Sandoval, Enrique; Ortega, Francisco Javier; García-Rayo, Manuel Ramón; Resines, Carlos

2008-12-01

302

ISABELLE cavity gap assemblies  

SciTech Connect

In a storage ring, where beam lifetime is measured in hours, it is necessary to keep the longitudinal impedance, as seen by the beam, very low, even into the gigahertz region. This is necessary to prevent the excitation of longitudinal instabilities. These impedances are due to the resistive wall effect and any deviation from a smooth vacuum chamber such as at pick-up electrodes, vacuum pump stations, rf cavities, etc. At low frequencies, up to 10 to 20 MHz, the low impedance requirement for the cavities can be satisfied by designing the driving power amplifiers with a very low output impedance. For ISABELLE a method has been designed for building a network into the cavity accelerating gaps which will satisfy the impedance criteria to at least 1300 MHz. The maximum allowable impedance at any frequency, f, is given in the form Z/n where n = f/f/sub rotation/. For the ISABELLE accelerating cavity, operating at 235.5 KHz, Z/n must be less than 10 ohms. For the stacking cavity, operating at 4.45 MHz, Z/n < 1 ohm.

Plotkin, M

1981-01-01

303

Research and Applications: Gap Analysis  

NSDL National Science Digital Library

The US Geological Survey's Gap Analysis Program (GAP) is a cooperative project that attempts to map land cover and vertebrate species distribution in order to enhance conservation land management activities. Visitors can view data about protected areas and species as well as read USGS publications on this program.

2001-01-01

304

Color Evaporation Induced Rapidity Gaps  

E-print Network

We show that soft color rearrangement of final states can account for the appearance of rapidity gaps between jets. In the color evaporation model the probability to form a gap is simply determined by the color multiplicity of the final state. This model has no free parameters and reproduces all data obtained by the ZEUS, H1, D0, and CDF collaborations.

O. J. P. Eboli; E. M. Gregores; F. Halzen

1999-08-16

305

Custom intramedullary intercalating device for treatment of supracondylar fracture between constrained total knee arthroplasty and well-fixed total hip arthroplasty.  

PubMed

Management of periprosthetic fractures between ipsilateral total knee arthroplasty (TKA) and total hip arthroplasty (THA) is difficult, and is further complicated in the setting of poor femoral bone stock. We present a case of supracondylar fracture between THA and long-stemmed TKA femoral components in a patient with rheumatoid arthritis, deficient metaphyseal bone stock, and recurrent fractures. A long custom intramedullary intercalating component was devised to link the well-fixed existing THA stem to a revision distal femoral component. The resulting construct was stable and allowed for full weight-bearing ambulation, representing a useful treatment option in the management of periprosthetic fractures between revision TKA and well-fixed THA. PMID:23266136

Newman, Erik T; Hug, Kevin T; Wellman, Samuel S; Bolognesi, Michael P; Kelley, Scott S

2014-03-01

306

Bridging the Vector Calculus Gap  

NSDL National Science Digital Library

This paper was written collaboratively by a physicist and a mathematician to raise awareness about the "vector calculus gap" and offer realistic solutions to bridge the gap. The authors define the vector calculus gap as a disparity between the way mathematicians and physical scientists think about vectors, which they argue results in performance difficulties for students of physics and engineering. In this paper, they advocate emphasizing geometric reasoning over algebraic computation when introducing vectors. In addition, their proposed instructional method uses differentials to bridge the vector calculus gap. Included are sample group activities and tips for incorporating these ideas in the classroom. SEE RELATED ITEMS BELOW for a link to the authors' full web site on Bridging the Vector Calculus Gap.

Dray, Tevian; Manogue, Corinne A.

2008-12-23

307

The Advantage of a Total Knee Arthroplasty with Rotating Platform is Only Theoretical: Prospective Analysis of 1,152 Arthroplasties  

PubMed Central

Background: The aim of total knee surgery is to provide patients with end-stage osteoarthritis of the knee with both pain relief and a functional range of motion with a securely fixed prosthesis for the long term. Many types of implants are designed to achieve these goals. Only clinical outcome studies are able to substantiate the superiority of one design over another. Our primary research question was to determine whether patients receiving a rotating platform implant had a better functional outcome. Methods: A total of 1,152 Performance Total Knee Arthroplastiesin 943 patients were studied prospectively. In 561 cases, the cruciate retaining model (CR) was used. In 591 cases the cruciate substituting with posterior-stabilized model (PS) was implanted (324 cases with a fixed bearing (PSFB) and 267 cases with a rotating platform (PSRP)). Results: The Clinical KSS score was similar for the three types at 1, 5, 10 and 15 years post-operatively. The Functional score also remained similar for all types until 10 years; at 15 years functional results of the CR group decreased. Conclusions: Neither clinically nor radiographically did the use of a rotating platform prove to be more advantageous than fixed bearing tibial components. Thus, the advantage of a Total Knee Arthroplasty with Rotating Platform remains theoretical. PMID:24339844

Delport, H.P.

2013-01-01

308

GAP Analysis Bulletin Number 15  

USGS Publications Warehouse

The Mission of the Gap Analysis Program (GAP) is to promote conservation by providing broad geographic information on biological diversity to resource managers, planners, and policy makers who can use the information to make informed decisions. As part of the National Biological Information Infrastructure (NBII) ?a collaborative program to provide increased access to data and information on the nation?s biological resources--GAP data and analytical tools have been used in hundreds of applications: from basic research to comprehensive state wildlife plans; from educational projects in schools to ecoregional assessments of biodiversity. The challenge: keeping common species common means protecting them BEFORE they become threatened. To do this on a state or regional basis requires key information such as land cover descriptions, predicted distribution maps for native animals, and an assessment of the level of protection currently given to those plants and animals. GAP works cooperatively with Federal, state, and local natural resource professionals and academics to provide this kind of information. GAP activities focus on the creation of state and regional databases and maps that depict patterns of land management, land cover, and biodiversity. These data can be used to identify ?gaps? in conservation--instances where an animal or plant community is not adequately represented on the existing network of conservation lands. GAP is administered through the U.S. Geological Survey. Through building partnerships among disparate groups, GAP hopes to foster the kind of collaboration that is needed to address conservation issues on a broad scale. For more information, contact: John Mosesso National GAP Director 703-648-4079 Kevin Gergely National GAP Operations Manager 208-885-3565

Maxwell, Jill, (Edited By); Gergely, Kevin; Aycrigg, Jocelyn; Canonico, Gabrielle; Davidson, Anne; Coffey, Nicole

2008-01-01

309

Results of revision total knee arthroplasty using press-fit cementless stem  

PubMed Central

OBJECTIVE: To show our experience with press-fit cementless stem and metaphyseal fixation with cement in a selected series of patients who underwent revision total knee arthroplasty. METHODS: Thirty-four patients (35 knees) underwent revision total knee arthroplasty using the press-fit technique. Minimum follow-up was one year (mean 2.2 years) with a maximum length of three years. RESULTS: Of 34 patients, 20 were women and 14 were men. There was one death due to causes not related to arthroplasty and one patient dropout. There were no cases in which further review was necessary. Patients who underwent revision had clinical and functional improvement demonstrated by the results of the KSS, results of the SF-36 quality of life questionnaire, through gains in range of motion and improved limb alignment. CONCLUSION: There was postoperative clinical and functional improvement in comparison to the preoperative status in revision total knee arthroplasty with press-fit cementless stem. Level of Evidence IV, Case series. PMID:24453638

Iamaguchi, Maurício Masasi; de Castro, Fernando Bley Vicente; Gobbi, Riccardo Gomes; Tirico, Luis Eduardo Passarelli; Pécora, José Ricardo; Camanho, Gilberto Luis

2013-01-01

310

Computer-assisted mosaic arthroplasty using patient-specific instrument guides  

E-print Network

computer model of bone and carti- lage, the harvesting of plugs and their placement at the defect siteKNEE Computer-assisted mosaic arthroplasty using patient-specific instrument guides Manuela Kunz was planned on the computer. Instrument guides were manufactured in thermoplastic on a 3D printer; the bottom

Waldman, Stephen D.

311

Lower-limb joint mechanics after total hip arthroplasty during sitting and standing tasks.  

PubMed

While the effect of total hip arthroplasty on the operated limb mechanics is well documented, little is known on its effect on the contralateral limb. The purpose of this study was to measure the joint mechanics of both lower limbs during the tasks of sit-to-stand and stand-to-sit. Twenty total hip arthroplasty patients and 20 control participants performed three trials of each task from which 3D lower-limb joint kinematics and kinetics were obtained. Total hip arthroplasty patients exhibited lower operated-hip joint flexion, extension moments, and power, occurring most frequently near seat-on and seat-off. Despite these reduced kinetic variables in the operated hip, the joints of the non-operated limb generated similar joint kinetics as the matched control participants. These results indicated the patients who underwent total hip arthroplasty could adopt a strategy that allowed them to reduce moments and power generated at the operated lower-limb joints without overcompensating with the non-operated leg. Although such a strategy may be desirable given that higher loads can increase friction and accelerate wear of the prosthesis, reduced loading may be an indication of inadequate muscle strength that needs to be addressed. PMID:22508467

Lamontagne, Mario; Beaulieu, Mélanie L; Varin, Daniel; Beaulé, Paul E

2012-10-01

312

Blood Management Strategies for Total Hip Arthroplasty in Jehovah's Witness Patients.  

PubMed

Total hip arthroplasty is associated with extensive blood loss, which is often corrected using allogeneic blood transfusions. However, Jehovah's Witnesses often refuse allogeneic blood transfusions or certain types of autologous blood transfusions due to their religious beliefs. This may represent a tremendous challenge for the orthopaedic surgeon and their team. Performing a total hip arthroplasty on a Jehovah's Witness patient requires a well-trained group of physicians willing to pre-operatively optimize the patient, attempt to minimize the blood loss during the surgery, adequately manage the post-operative period, and be aware of which of the life-saving strategies can be used in these patients during an emergency situation. Ultimately, physicians should be prepared to deal with marked blood loss and respect the patients' wishes, values, and beliefs. This review focuses on studies where primary or revision total hip arthroplasty was performed in Jehovah's Witness patients. Therefore, we will illustrate that with a prepared team and an optimized patient, it is potentially quite safe to perform total hip arthroplasties in Jehovah's Witness patients. PMID:24347482

Jauregui, Julio J; Kapadia, Bhaveen H; Banerjee, Samik; Issa, Kimona; Su, Sherwin; Harwin, Steven F; Mont, Michael A

2014-03-01

313

Solid organ transplant patients experience high rates of infection and other complications after total knee arthroplasty.  

PubMed

Survival after solid organ transplants in the United States is increasing, and there is a need to understand the complications in knee arthroplasty patients who underwent organ transplantation. A retrospective study was conducted from 1993-2008 on 19 patients (23 knee arthroplasties) with previous successful solid organ transplants. Eleven knee arthroplasties were performed after renal transplantation, and 12 after nonrenal solid organ transplant (seven liver, four heart, one lung). Complications occurred in 9/23 patients (39.1%) and infections occurred in 4/23 patients (17.3%). Of the infected knees, two had MRSA, one had MSSA, and one Escherichia coli. Noninfectious complications (5/24, 21.7%) include aseptic loosening, quadriceps rupture, femoral fracture, hemarthrosis, and arthrofibrosis. All patients with complications were on immunosuppressant medications at the time of arthroplasty. There was a significantly higher rate of infection in the renal group compared to the non-renal group (P = 0.022). There was also a higher overall complication rate in the renal group however this did not reach significance. PMID:23558242

Klatt, Brian A; Steele, G Daxton; Fedorka, Catherine J; Sánchez, Alvaro I; Chen, Antonia F; Crossett, Lawrence S

2013-06-01

314

Experience with Computer-Assisted Navigation for Total Knee Arthroplasty in a Community Setting  

Microsoft Academic Search

This study analyzed the initial experience with computer-assisted navigation for total knee arthroplasty (TKA) in a community hospital. One hundred TKAs performed with a navigation system were compared with 100 performed conventionally. Component alignment results, measured by computed tomography, were grouped as good, fair, poor, or extremely poor, based on deviation from the surgical goal. More navigated knees were classified

Ralph E. Carter; Paul F. Rush; John A. Smid; Whitney L. Smith

2008-01-01

315

Analyzing total knee arthroplasty using surgical volume of different hospital levels  

Microsoft Academic Search

The purpose of this research is to discover valuable medical facts by mining TKA (total knee arthroplasty) surgical volume of three different hospital levels from Taiwan NHI (National Health Insurance) database. In this paper, there are three main objectives provided: (1) to build up the learning curves using the patients¿ outcomes of three different hospital levels; (2) to characterize whether

Y. T. Cheng; C. H. Cheng; J. S. Chen

2008-01-01

316

Lunar phase does not influence perioperative complications in total hip arthroplasty  

PubMed Central

Introduction Lunar calendars, publishing recommendations for daily life, are gaining more and more attention in Germany, where 10.5% of the population believe in lunar effects on disease. A widespread and often heard belief is that a full moon has the most negative effects on surgical outcome. The present study evaluates the effects of lunar phase on perioperative complications in total hip arthroplasty. Material and methods We performed a retrospective study with 305 patients being provided with a primary hip arthroplasty. To identify possible influences of the lunar phase on perioperative complications we investigated data such as operation length, blood loss and course of C-reactive protein that were collected during the patients’ stay in the hospital and allocated them to moon illumination. Results There were no significant differences in all collected data concerning the lunar phase (p > 0.05). Although not statistically significant, there were fewer operations during the full moon phase. Conclusions Therefore there is no evidence that lunar phase has an effect on perioperative complications in total hip arthroplasty. Fewer, though not significantly fewer, operations were performed during the full moon phase. Although this was not a prospective randomized trial, the statistical magnitude of the results does not support any recommendations for scheduling patients for total hip arthroplasty at any particular day of the lunar phase. PMID:22457684

Angermann, Alexander; Weber, Patrick; Wegener, Bernd; Pietschmann, Matthias; Muller, Peter

2012-01-01

317

Transition from nerve blocks to periarticular injections and emerging techniques in total joint arthroplasty.  

PubMed

The emergence of procedure-specific multimodal pain management regimens that provide effective control of postoperative pain, while markedly reducing the amount of opioid medication required, has been one of the most important advances in hip and knee replacement in recent years. When peripheral nerve blockade first became widely available for inclusion in multimodal regimens, it was viewed as a revolution in the management of postoperative pain. This approach, however, is costly and has some important limitations, including an increased incidence of falls. For many patients, peripheral nerve blocks can now be replaced by a periarticular injection with EXPAREL® (bupivacaine liposome injectable suspension), an extended-release anesthetic infiltrated by the surgeon as part of a multimodal pain regimen. EXPAREL® offers some important clinical and administrative benefits over nerve blocks. Preliminary data from a pilot study comparing the relative effectiveness of EXPAREL® versus sciatic nerve blockade has shown a noticeable reduction in average pain scores at rest with EXPAREL® following both hip and knee arthroplasty, as well as a reduction in the 6- to 12-hour pain score following hip arthroplasty. There was also a significant reduction in opioid use with EXPAREL®, as well as a $411 reduction in the cost of total knee arthroplasty and a $348 reduction in the cost of total hip arthroplasty. PMID:25303457

Springer, Bryan D

2014-10-01

318

Numerical simulation of an osteoporotic Before and after total hip arthroplasty.  

E-print Network

osteoporosis. This disease weakens the bone structure and causes bone fractures. Among those fractures, femoral of the distal part at the end of the stem. KEY-WORDS : Osteoporosis, total hip arthroplasty, 3D- reconstruction like osteoporosis which deteriorates bone strength. In Europe, the most consequences of osteoporosis

Paris-Sud XI, Université de

319

Influence of the Emotional Response to Surgery on Functional Recovery During 6 Months After Hip Arthroplasty  

Microsoft Academic Search

We examined whether the emotional response to hip arthroplasty predicted functional recovery after controlling for preoperative function and surgical trauma. Mood and fatigue were measured in 102 consecutive patients preoperatively and 3 days postoperatively. Time of achievement of functional milestones indicated recovery in hospital, and functional status was measured preoperatively and 1 and 6 months postoperatively. Circulating C-reactive protein and

Peter Salmon; George M. Hall; Denise Peerbhoy

2001-01-01

320

Observed kneeling ability after total, unicompartmental and patellofemoral knee arthroplasty: perception versus reality  

Microsoft Academic Search

Kneeling is an important function of the knee, but little information is available on ability to kneel after different knee arthroplasty procedures. Previous work has asked patients about their kneeling ability; in this study it was objectively assessed. One hundred and twenty two patients — 38 having had total knee replacement (TKR), 53 unicompartmental knee replacement (UKR), 31 patello-femoral replacement

M. A. Hassaballa; A. J. Porteous; J. H. Newman

2004-01-01

321

An Evaluation of Information Available on the Internet Regarding Minimally Invasive Hip Arthroplasty  

Microsoft Academic Search

The Internet is a popular source of information regarding health care especially when seeking advice on new and less invasive surgical techniques. We evaluated 150 Web sites (3 search engines) for authorship and quality of information regarding minimally invasive hip arthroplasty. The results revealed that 45% were authored by a hospital\\/university, 26% were news stories, 25% were private medical groups,

Ryan Scott Labovitch; Kevin J. Bozic; Erik Hansen

2006-01-01

322

Effects of shoulder arthroplasty and exercise in patients with rheumatoid arthritis  

Microsoft Academic Search

The aim of this study was to examine pain and shoulder function in patients with rheumatoid arthritis (RA) before and after shoulder arthroplasty and postoperative exercise. Twenty-four patients (26 shoulders) were consecutively included in a multicentre study. Before surgery, at discharge from hospital and after 3 and 6 months, perceived shoulder function and shoulder pain were assessed by visual analogue scales,

Anne Marit Mengshoel; Bente Slungaard

2005-01-01

323

Quadriceps strength and volitional activation before and after total knee arthroplasty for osteoarthritis  

Microsoft Academic Search

Introduction: Patients with osteoarthritis (OA) of the knee have quadriceps weakness and arthrogenous muscle inhibition (AMI). While total knee arthroplasty (TKA) reliably reduces pain and improves function in patients with knee OA, quadriceps weakness persists after surgery. The purpose of this investigation was to assess contributions of AMI to quadriceps weakness before and after TKA and to assess the effect

Jennifer E. Stevens; Ryan L. Mizner; Lynn Snyder-Mackler

2003-01-01

324

Association of Increased Knee Flexion and Patella Clunk Syndrome After Mini-Subvastus Total Knee Arthroplasty  

Microsoft Academic Search

This study reviewed 747 consecutive posterior stabilized total knee arthroplasty (TKA) to explain the increased incidence of patella clunk syndrome that occurred when the surgeon switched from a medial parapatellar arthrotomy to a mini-subvastus (MIS) TKA technique. The incidence of patella clunk syndrome increased with increased postoperative knee flexion. Six weeks after surgery, knees that developed patella clunk had a

William C. Schroer; Paul J. Diesfeld; Mary E. Reedy; Angela LeMarr

2009-01-01

325

The role of patient expectations in predicting outcome after total knee arthroplasty  

Microsoft Academic Search

INTRODUCTION: Patient's expectations are variably reported to influence self-rated outcome and satisfaction after medical treatment; this prospective study examined which of the following was the most important unique determinant of global outcome\\/satisfaction after total knee arthroplasty (TKA): baseline expectations; fulfilment of expectations; or current symptoms and function. METHODS: One hundred and twelve patients with osteoarthritis of the knee (age, 67

Anne F Mannion; Stephane Kämpfen; Urs Munzinger; Ines Kramers-de Quervain

2009-01-01

326

Sports activities 5 years after total knee or hip arthroplasty: the Ulm Osteoarthritis Study  

Microsoft Academic Search

Objective: To analyse sports activities of patients with hip or knee osteoarthritis (OA) over lifetime, preoperatively, and 5 years after arthroplasty.Methods: In a longitudinal four centre study, 809 consecutive patients with advanced OA of the hip (420) or the knee (389) joint under the age of 76 years who required total joint replacement were recruited. A completed questionnaire about sports

K Huch; K A C Mu?ller; T Stu?rmer; H Brenner; W Puhl; K-P Gu?nther

2005-01-01

327

The Incidence of Venous Emboli During Extramedullary Guided Total Knee Arthroplasty  

Microsoft Academic Search

During total knee arthroplasty (TKA), instrumenta- tion of the marrow cavity with an intramedullary guide appears responsible for fatal intraoperative pulmonary embolism. Transesophageal echocardi- ography demonstrates venous emboli (VE) after tourniquet deflation during intramedullary guided TKA. Extramedullary guides avoid manipulating the marrow cavity. We determined the incidence of VE in 20 patients undergoing extramedullary guided TKA. Recordings of hemodynamic variables,

Jonathan L. Parmet; Jan C. Horrow; Gregory Pharo; Lawrence Collins; Arnold T. Berman; Henry Rosenberg

1996-01-01

328

Analgesia After Total Hip Arthroplasty: New Landmarks, Technical Guidelines, and Clinical Evaluation  

Microsoft Academic Search

A computed tomographic scan was obtained in 35 patients to measure the depth and the relationship of the branches of the lumbar plexus to the posterior superior iliac spine projec- tion and the vertebral column. In addition, we prospectively studied 80 patients scheduled for total hip arthroplasty who received a continuous psoas compartment block (CPCB) in the postoperative period. CPCB

Xavier Capdevila; Philippe Macaire; Christophe Dadure; Olivier Choquet; Philippe Biboulet; Yves Ryckwaert; Francoise d'Athis

329

Variation in the wear rate during the life of a total hip arthroplasty  

Microsoft Academic Search

The limitation of wear is fundamental to the optimization of total hip arthroplasty longevity. The maintenance of the supersmooth femoral head surface is considered to be paramount in maximizing prosthesis life expectancy. Ex vivo studies have failed to substantiate a relationship between roughness and the clinical wear factor, however. A hip simulator wear study was undertaken to investigate this contradiction.

Alistair P. D. Elfick; Simon L. Smith; Anthony Unsworth

2000-01-01

330

A comprehensive joint replacement program for total knee arthroplasty: a descriptive study  

Microsoft Academic Search

BACKGROUND: Total knee arthroplasty (TKA) is a commonly performed surgical procedure in the US. It is important to have a comprehensive inpatient TKA program which maximizes outcomes while minimizing adverse events. The purpose of this study was to describe a TKA program – the Joint Replacement Program (JRP) – and report post-surgical outcomes. METHODS: 74 candidates for a primary TKA

Jon R Cook; Meghan Warren; Kathleen J Ganley; Paul Prefontaine; Jack W Wylie

2008-01-01

331

Patella resurfacing: no benefit for the long-term outcome of total knee arthroplasty  

Microsoft Academic Search

. A follow-up of more than 10 years among patients who have undergone a total knee arthroplasty (TKA) was performed to determine the significance of patella resurfacing for the long-term outcome. The clinical outcome was assessed by the Knee Society Score (KSS), and the radiological outcome was determined based on the Knee Society Roentgenographic Evaluation System. The patella was preserved

Michael Ogon; Frank Hartig; Christian Bach; Michael Nogler; Iris Steingruber; Rainer Biedermann

2002-01-01

332

Fracture of the femoral component associated with polyethylene wear and osteolysis after total knee arthroplasty  

Microsoft Academic Search

Fracture of the femoral component associated with polyethylene wear and osteolysis after total knee arthroplasty (TKA) has not been well reported before. A 63-year-old man with osteoarthritis of the right knee underwent TKA with a New Jersey LCS Knee, with cementing on the tibia and patella but not on the femoral component. After 42 months, in addition to wearing of

Chun-Hsiung Huang; Chyun-Yu Yang; Cheng-Kung Cheng

1999-01-01

333

Retrograde intramedullary nailing of supracondylar femur fractures above total knee arthroplasty  

Microsoft Academic Search

Four supracondylar fractures of the femur in three patients with total knee arthroplasties were treated by retrograde intramedullary nailing using an interlocking reamed nail (GSH Nail, Smith and Nephew Richards, Memphis, TN) specifically designed for fractures of the distal femur. Three cases were acute fractures and one was a refracture through a screw hole of a previously plated supracondylar fracture.

Felix F. Jabczenski; Mark Crawford

1995-01-01

334

Bryan total disc arthroplasty: a replacement disc for cervical disc disease  

PubMed Central

Total disc arthroplasty is a new option in the treatment of cervical degenerative disc disease. Several types of cervical disc prostheses currently challenge the gold-standard discectomy and fusion procedures. This review describes the Bryan Cervical Disc System and presents the Bryan prosthesis, its indications, surgical technique, complications, and outcomes, as given in the literature. PMID:22915917

Wenger, Markus; Markwalder, Thomas-Marc

2010-01-01

335

Conversion of Fused Hip to Total Hip Arthroplasty With Presurgical and Postsurgical Gait Studies  

Microsoft Academic Search

This case study presents a subject with a fused hip converted to total hip arthroplasty. Kinematic gait analysis was conducted on 3 occasions, presurgery, 4 months postsurgery, and 2.5 years postsurgery. Presurgery data showed decreased cadence and shorter step length; sound limb possessed increased hip, knee range of motion (ROM), and increased knee flexion during stance; the affected limb had

Stephanie J. Bonin; Moataz A. Eltoukhy; W. Andrew Hodge; Shihab S. Asfour

336

Effect of osteoprotegerin and osteoprotegerin ligand on osteoclast formation by arthroplasty membrane derived macrophages  

Microsoft Academic Search

OBJECTIVEOsteoprotegerin ligand (OPGL) is a newly discovered molecule, which is expressed by osteoblasts\\/bone stromal cells. This ligand and M-CSF are now known to be essential for osteoclast differentiation from marrow and circulating precursors. This study examined whether OPGL and its soluble receptor osteoprotegerin (OPG), influenced osteoclast formation from human arthroplasty derived macrophages, to determine if the effects of OPGL and

I Itonaga; A Sabokbar; D W Murray; N A Athanasou

2000-01-01

337

[Imaging of total hip arthroplasty: normal and pathological imaging features, role of ultrasound, CT and MRI].  

PubMed

Total hip arthroplasty is a frequent procedure with functional outcome that generally is excellent and lasting. Routine imaging follow-up is necessary to detect complications such as loosening and wearing out. Additional imaging with scintigraphy, CT, ultrasound or MRI may be necessary. PMID:21704254

Fantino, O; Tayot, O; Sans, N; Cyteval, C

2011-06-01

338

Complications and short-term outcomes associated with total hip arthroplasty in teaching and community hospitals  

Microsoft Academic Search

We followed 1,810 consecutive admissions for elective total hip arthroplasty (excluding hip fracture repair and revisions) to 27 Minnesota hospitals in a prospective study to assess the factors associated with better outcomes. Patients were interviewed before surgery and at 6 months, and their medical records were reviewed. The operative complication rate was 6.1%. In general, neither surgeon nor hospital volume

Roby Thompson; Robert L. Kane; Terry Gromala; Barbara McLaughlin; Shannon Flood; Nora Morris; Catherine Borbas

2002-01-01

339

Lower Limbs Function and Pain Relationships after Unilateral Total Knee Arthroplasty  

ERIC Educational Resources Information Center

The aim of the study was to evaluate gait characteristics, lower limbs joint function, and pain relationships associated with knee osteoarthritis of female patients before and 3 months after total knee arthroplasty at an outpatient clinic rehabilitation department. Gait parameters were registered, the active range of lower extremity joints was…

Tali, Maie; Maaroos, Jaak

2010-01-01

340

Patellofemoral contact pressures exceed the compressive yield strength of UHMWPE in total knee arthroplasties  

Microsoft Academic Search

To address mechanisms involved in wear and permanent deformation of patellofemoral components in total knee arthroplasties, a previously reported knee joint loading model and pressure-sensitive film were used to measure patellofemoral contact areas and pressures in human cadaver knee joints after implantation with six different total knee joint designs. The joints were tested at three different Q angles (physiologic, ?10°,

Toshitsugu Takeuchi; Vijay K. Lathi; Amir M. Khan; Wilson C. Hayes

1995-01-01

341

Histologic findings of periprosthetic tissues retrieved during revision of cementless hip arthroplasties  

Microsoft Academic Search

. The authors evaluated the histological findings from periprosthetic material retrieved around acetabular and femoral components of 24 revision operations from 24 patients who had previously received cementless total hip arthroplasty or hemiarthroplasty. The indication for revision was aseptic loosening in 20 patients, technical error during implantation in two patients, periprosthetic femoral fracture with subsequent loosening in one patient, and

M. Repanti; M. Stamatakis; A. Baikousis; Z. Papazisis; P. Korovessis

2002-01-01

342

Fast-track hip and knee arthroplasty: clinical and organizational aspects.  

PubMed

Fast-track hip and knee arthroplasty aims at giving the patients the best available treatment at all times, being a dynamic entity. Fast-track combines evidence-based, clinical features with organizational optimization including a revision of traditions resulting in a streamlined pathway from admission till discharge – and beyond. The goal is to reduce morbidity, mortality and functional convalescence with an earlier achievement of functional milestones including functional discharge criteria with subsequent reduced length of stay and high patient satisfaction. Outcomes are traditionally measured as length of stay; safety aspects in the form of morbidity/mortality; patient satisfaction; and – as a secondary parameter – economic savings. Optimization of the clinical aspects include focusing on analgesia; DVT-prophylaxis; mobilization; care principles including functional discharge criteria; patient-characteristics to predict outcome; and traditions which may be barriers in optimizing outcomes. Patients should be informed and motivated to be active participants and their expectations should be modulated in order to improve satisfaction. Also, organizational aspects need to be analyzed and optimized. New logistical approaches should be implemented; the ward ideally (re)structured to only admit arthroplasties; the staff educated to have a uniform approach; extensive preoperative information given including discharge criteria and intended length of stay. This thesis includes 9 papers on clinical and organizational aspects of fast-track hip and knee arthroplasty (I–IX). A detailed description of the fast-track set-up and its components is provided. Major results include identification of patient characteristics to predict length of stay and satisfaction with different aspects of the hospital stay (I); how to optimize analgesia by using a compression bandage in total knee arthroplasty (II); the clinical and organizational set-up facilitating or acting as barriers for early discharge (III); safety aspects following fast-track in the form of few readmissions in general (IV) and few thromboembolic complications in particular (V); feasibility studies showing excellent outcomes following fast-track bilateral simultaneous total knee arthroplasty (VI) and non-septic revision knee arthroplasty (VII); how acute pain relief in total hip arthroplasty is not enhanced by the use of local infiltration analgesia when multi-modal opioid-sparing analgesia is given (VIII); and a detailed description of which clinical and organizational factors detain patients in hospital following fast-track hip and knee arthroplasty (IX). Economic savings following fast-track hip and knee arthroplasty is also documented in studies, reviews, metaanalyses and Cochrane reviews – including the present fast-track (ANORAK). In conclusion, the published results (I–IX) provide substantial, important new knowledge on clinical and organizational aspects of fast-track hip and knee arthroplasty – with concomitant documented high degrees of safety (morbidity/mortality) and patient satisfaction. Future research strategies are multiple and include both research strategies as efforts to implement the fast-track methodology on a wider basis. Research areas include improvements in pain treatment, blood saving strategies, fluid plans, reduction of complications, avoidance of tourniquet and concomitant blood loss, improved early functional recovery and muscle strengthening. Also, improvements in information and motivation of the patients, preoperative identification of patients needing special attention and detailed economic studies of fast- track are warranted. PMID:23205862

Husted, Henrik

2012-10-01

343

Pneumatic gap sensor and method  

SciTech Connect

An apparatus and method for monitoring and maintaining a predetermined width in the gap between a casting nozzle and a casting wheel, wherein the gap is monitored by means of at least one pneumatic gap sensor. The pneumatic gap sensor is mounted on the casting nozzle in proximity to the casting surface and is connected by means of a tube to a regulator and a transducer. The regulator provides a flow of gas through a restictor to the pneumatic gap sensor, and the transducer translates the changes in the gas pressure caused by the proximity of the casting wheel to the pneumatic gap sensor outlet into a signal intelligible to a control device. The relative positions of the casting nozzle and casting wheel can thereby be selectively adjusted to continually maintain a predetermined distance between their adjacent surfaces. The apparatus and method enables accurate monitoring of the actual casting gap in a simple and reliable manner resistant to the extreme temperatures and otherwise hostile casting environment.

Bagdal, Karl T. (Middletown, OH); King, Edward L. (Trenton, OH); Follstaedt, Donald W. (Middletown, OH)

1992-01-01

344

Pneumatic gap sensor and method  

DOEpatents

An apparatus and method for monitoring and maintaining a predetermined width in the gap between a casting nozzle and a casting wheel, wherein the gap is monitored by means of at least one pneumatic gap sensor. The pneumatic gap sensor is mounted on the casting nozzle in proximity to the casting surface and is connected by means of a tube to a regulator and a transducer. The regulator provides a flow of gas through a restictor to the pneumatic gap sensor, and the transducer translates the changes in the gas pressure caused by the proximity of the casting wheel to the pneumatic gap sensor outlet into a signal intelligible to a control device. The relative positions of the casting nozzle and casting wheel can thereby be selectively adjusted to continually maintain a predetermined distance between their adjacent surfaces. The apparatus and method enables accurate monitoring of the actual casting gap in a simple and reliable manner resistant to the extreme temperatures and otherwise hostile casting environment. 6 figs.

Bagdal, K.T.; King, E.L.; Follstaedt, D.W.

1992-03-03

345

A resident survey study of orthopedic fellowship specialty decision making and views on arthroplasty as a career.  

PubMed

A dramatic shortage of total hip arthroplasty (THA) and total knee arthroplasty (TKA) surgeons has been projected because fewer residents enter arthroplasty fellowships, and the demand for THAs/TKAs is rising. The purposes of this study were to ascertain the future supply of THA/TKA surgeons, to identify the criteria residents use to choose their fellowship specialty, and to assess resident perceptions of an arthroplasty career. Four hundred ninety-eight post-graduate year 3 and above residents completed the online survey. Residents most highly prioritize intellectual factors and role models/mentors in determining their fellowship specialty. In the face of a looming patient access-to-care crisis, the data from this study support a policy of highlighting the intellectual challenges and satisfaction of THA/TKA as a career and encouraging mentorship early in a resident's training. PMID:21130602

Hariri, Sanaz; York, Sally C; O'Connor, Mary I; Parsley, Brian S; McCarthy, Joseph C

2011-09-01

346

Technique and application of a non-invasive three dimensional image matching method for the study of total shoulder arthroplasty  

E-print Network

Knowledge of in-vivo glenohumeral joint biomechanics after total shoulder arthroplasty are important for the improvement of patient function, implant longevity and surgical technique. No data has been published on the ...

Massimini, Daniel Frank

2009-01-01

347

Outcomes Study of the TM Reverse Shoulder System Used in Primary or Revision Reverse Total Shoulder Arthroplasty  

ClinicalTrials.gov

Osteoarthritis; Rheumatoid Arthritis; Post-traumatic Arthritis; Ununited Humeral Head Fracture; Irreducible 3-and 4-part Proximal Humeral Fractures; Avascular Necrosis; Gross Rotator Cuff Deficiency; Failed Total Shoulder Arthroplasty (Both Glenoid and Humeral Components Require Revision

2014-05-14

348

A Mouse Model of Post-Arthroplasty Staphylococcus aureus Joint Infection to Evaluate In Vivo the Efficacy of Antimicrobial Implant Coatings  

Microsoft Academic Search

BackgroundPost-arthroplasty infections represent a devastating complication of total joint replacement surgery, resulting in multiple reoperations, prolonged antibiotic use, extended disability and worse clinical outcomes. As the number of arthroplasties in the U.S. will exceed 3.8 million surgeries per year by 2030, the number of post-arthroplasty infections is projected to increase to over 266,000 infections annually. The treatment of these infections

Nicholas M. Bernthal; Alexandra I. Stavrakis; Fabrizio Billi; John S. Cho; Thomas J. Kremen; Scott I. Simon; Ambrose L. Cheung; Gerald A. Finerman; Jay R. Lieberman; John S. Adams; Lloyd S. Miller; Paul J. Planet

2010-01-01

349

Results of Revision Surgery and Causes of Unstable Total Knee Arthroplasty  

PubMed Central

Background The aim of this study was to evaluate causes of unstable total knee arthroplasty and results of revision surgery. Methods We retrospectively reviewed 24 knees that underwent a revision arthroplasty for unstable total knee arthroplasty. The average follow-up period was 33.8 months. We classified the instability and analyzed the treatment results according to its cause. Stress radiographs, postoperative component position, and joint level were measured. Clinical outcomes were assessed using the Hospital for Special Surgery (HSS) score and range of motion. Results Causes of instability included coronal instability with posteromedial polyethylene wear and lateral laxity in 13 knees, coronal instability with posteromedial polyethylene wear in 6 knees and coronal and sagittal instability in 3 knees including post breakage in 1 knee, global instability in 1 knee and flexion instability in 1 knee. Mean preoperative/postoperative varus and valgus angles were 5.8°/3.2° (p = 0.713) and 22.5°/5.6° (p = 0.032). Mean postoperative ?, ?, ?, ? angle were 5.34°, 89.65°, 2.74°, 6.77°. Mean changes of joint levels were from 14.1 mm to 13.6 mm from fibular head (p = 0.82). The mean HSS score improved from 53.4 to 89.2 (p = 0.04). The average range of motion was changed from 123° to 122° (p = 0.82). Conclusions Revision total knee arthroplasty with or without a more constrained prosthesis will be a definite solution for an unstable total knee arthroplasty. The solution according to cause is very important and seems to be helpful to avoid unnecessary over-constrained implant selection in revision surgery for total knee instability. PMID:24900897

Sun, Doo-Hoon; Chon, Jae-Gyun; Jang, Sung-Won; Sun, Dong-Hyuk

2014-01-01

350

Deep vein thrombosis after reconstructive shoulder arthroplasty: a prospective observational study.  

PubMed

This clinical study was performed to document the prevalence of deep vein thrombosis (DVT) after prosthetic shoulder replacement surgery. We prospectively followed 100 consecutive shoulder arthroplasty procedures (total shoulder replacement in 73 and hemiarthroplasty in 27) in 44 male and 56 female patients for 12 weeks (mean age, 67 years; range, 17-88 years). Risk factors for venous thromboembolic disease were assessed preoperatively and postoperatively. A 4-limb surveillance color flow Doppler ultrasound was performed at 2 days (100 patients) and 12 weeks (50 patients randomly selected) after surgery, and the presence and location of DVT were recorded. Postoperative symptomatic or fatal pulmonary emboli (PE) were also recorded. The overall prevalence of DVT was 13.0%, consisting of 13 DVTs in 12 patients. These included 6 ipsilateral and no contralateral upper extremity DVTs and 5 ipsilateral and 2 contralateral lower extremity DVTs. The prevalence of DVT was 10.0% (10/100) at day 2 after surgery and 6.0% (3/50) at week 12 after surgery. The incidence of symptomatic nonfatal PE was 2.0% (2/100), and that of fatal PE was 1.0% (1/100). Risk factors associated with venous thromboembolic disease did not reach statistical significance because of the small study population sample size. At our institution, the prevalence of DVT after reconstructive shoulder arthroplasty was 13.0%, a rate comparable to that after hip arthroplasty (10.3%) but lower than that after knee arthroplasty (27.2%). Shoulder arthroplasty surgeons should be aware of the potential risk of perioperative thromboembolic complications in both the acute and subacute postoperative periods. PMID:19095183

Willis, Andrew A; Warren, Russell F; Craig, Edward V; Adler, Ronald S; Cordasco, Frank A; Lyman, Stephen; Fealy, Stephen

2009-01-01

351

Comparative responsiveness of outcome measures for total knee arthroplasty  

PubMed Central

Summary Objective The aim of this study was to compare the responsiveness of various patient-reported outcome measures (PROMs) and clinician-reported outcomes following total knee arthroplasty (TKA) over a 2-year period. Methods Data were collected in a prospective cohort study of primary TKA. Patients who had completed Forgotten Joint Score-12 (FJS-12), Western Ontario and McMaster Universities (WOMAC) osteoarthritis (OA) index, EQ-5D, Knee Society Score and range of movement (ROM) assessment were included. Five time points were assessed: pre-operative, 2 months, 6 months, 1 year and 2 years post-operative. Results Data from 98 TKAs were available for analysis. Largest effect sizes (ES) for change from pre-operative to 2-month follow-up were observed for the Knee Society Score (KSS) Knee score (1.70) and WOMAC Total (?1.50). For the period from 6 months to 1 year the largest ES for change were shown by the FJS-12 (0.99) and the KSS Function Score (0.88). The EQ-5D showed the strongest ceiling effect at 1-year follow-up with 84.4% of patients scoring the maximum score. ES for the time from 1- to 2-year follow-up were largest for the FJS-12 (0.50). All other outcome measures showed ES equal or below 0.30. Conclusion Outcome measures differ considerably in responsiveness, especially beyond one year post-operatively. Joint-specific outcome measures are more responsive than clinician-reported or generic health outcome tools. The FJS-12 was the most responsive of the tools assessed; suggesting that joint awareness may be a more discerning measure of patient outcome than traditional PROMs. PMID:24262431

Giesinger, K.; Hamilton, D.F.; Jost, B.; Holzner, B.; Giesinger, J.M.

2014-01-01

352

[Ligament instability in total knee arthroplasty--causal analysis].  

PubMed

Ligament instability is a common reason for revision total knee arthroplasty (TKA). A meticulous analysis of the type of instability is very important in order to revise such a knee successfully. The objective of this study was to analyze the different reasons for ligament instability in revision TKA. A total of 135 knee revisions performed by one surgeon were analyzed pre- (clinical and x-ray) and intraoperatively for the cause of failure. X-ray analysis included the assessment of each component for position. Intraopertive analysis included stability testing in extension and 30 degrees , and 90 degrees of flexion, wear pattern, patella motion (shifting and tilting) and patella height. In 32.6 % of all cases, ligament instability was the primary reason for revision. In another 21.6%, ligament instability was identified as a secondary reason for revision. Analysis of the different instability forms showed combined instability in extension and flexion as the most common cause, followed by isolated instability in flexion (31.8%) and isolated instability in extension (9.1%). The high correlation between instability and malpositioning of the prostheses was obvious. Often, an isolated femoral malposition, in particular for rotation, was found, as well as an isolated malposition of the tibia component. In summary, ligament instability is a common reason for revision TKA. Many different forms of instability can be found either as isolated or combined instability types. Correct anatomical positioning of the components and balanced ligaments in the different extension and flexion positions are important for good clinical results, a stable joint, good function and longevity. PMID:17581739

Graichen, H; Strauch, M; Katzhammer, T; Zichner, L; von Eisenhart-Rothe, R

2007-07-01

353

Daptomycin-loaded polymethylmethacrylate bone cement for joint arthroplasty surgery.  

PubMed

Antibiotic-loaded acrylic bone cement has been frequently used as an infection prophylaxis or antibiotic-loaded spacer in infected arthroplasty. In addition, daptomycin has been used recently against broad spectrum Gram-positive organisms. The goal of this in vitro study is to investigate the bacteriacidal and mechanical properties of daptomycin-incorporated polymethylmethacrylate (PMMA) bone cement and evaluate its feasibility for clinical use. Daptomycin (0.5, 1, or 2?g) was premixed with 40?g of PMMA bone cement powder before curing. The mechanical properties of the daptomycin-loaded acrylic bone cement (DLABC) were estimated following standard guidance, and the release profile and kinetics of daptomycin from PMMA were analyzed. The antimicrobial efficacy of DLABC was determined with a zone of inhibition (ZOI) assay against Staphylococcus aureus, Staphylococcus epidermis, Enterococcus faecalis, and Enterococcus faecium, respectively. The results showed that the compressive strength, of PMMA bone cement, which was higher than 100 MPa in all groups, was sufficient according to ISO 5833 after incorporation of daptomycin. The encapsulated daptomycin was released for 2 weeks with a 9.59?±?0.85%, 15.25?±?0.69%, and 20.64?±?20.33% released percentage on the first day in the low, mid, and high groups, respectively. According to the calculated release kinetics, incorporated daptomycin should be 3.3 times the original dose to double its release. Although all recipes of DLABC had a microbial inhibitory effect, the effect with a higher encapsulated amount of daptomycin was more significant. Therefore, we believe that daptomycin can be locally delivered from PMMA bone cement at the surgical site as a prophylactic or treatment for osteomyelitis against Gram-positive organisms with intact cement function. PMID:24571555

Hsu, Yuan-Ming; Liao, Chun-Hsing; Wei, Yu-Hong; Fang, Hsu-Wei; Hou, Hsiang-Huan; Chen, Chia-Chun; Chang, Chih-Hung

2014-06-01

354

Utility of week one radiographs post total hip arthroplasty  

PubMed Central

Introduction We retrospectively analysed 129 consecutive patients who underwent hip arthroplasty at a university-affiliated hospital in Melbourne, Australia between February and September 2011 with respect to the quality of the week one radiographs, placement of the prosthesis and the presence of a peri-prosthetic fracture or dislocation. Method Patient records and radiographs were reviewed to ascertain whether a deviation in routine management occurred based on the information obtained from week one post-operative radiographs. Results 116 of the 129 patients met the inclusion criteria for the study. 115 patients underwent routine week one hip radiographs with a mean time after surgery of 2.5 days. 89 (77%) of these patients had radiographs with a typical post-operative appearance. 26 (23%) had radiographs with an atypical appearance defined by the presence of one or more of the following: offset difference of >10 mm (11%), leg length difference of >10 mm (11%), sub-optimal acetabular component inclination of <30° or >50° (9%), sub-optimal femoral stem position of >5° varus or valgus (2%), sub-optimal femoral Greun cement distribution of 2 or more absent zones (2%), cement extrusion (1%), peri-prosthetic fracture (0) or dislocation (0). None of the routine week one radiographs resulted in a change in early post-operative management. 1 patient underwent non-routine, immediate post-operative radiographs. Discussion Our study did not demonstrate a case where deviation from standard clinical pathways occurred as a result of routine post-operative radiographs. A higher power study would help the established surgeon to determine whether post-operative radiographs could be performed at a more comfortable and convenient time such as the outpatient setting. PMID:24396226

Stevens, Jarrad; van Tonder, Frans; Schlicht, Stephen; Love, Bruce; Goldwasser, Miron; Choong, Peter

2013-01-01

355

Impingement and Dislocation in Total HIP Arthroplasty: Mechanisms and Consequences  

PubMed Central

In contemporary total hip arthroplasty, instability has been a complication in approximately 2% to 5% of primary surgeries and 5% to 10% of revisions. Due to the reduction in the incidence of wear-induced osteolysis that has been achieved over the last decade, instability now stands as the single most common reason for revision surgery. Moreover, even without frank dislocation, impingement and subluxation are implicated in a set of new concerns arising with advanced bearings, associated with the relatively unforgiving nature of many of those designs. Against that backdrop, the biomechanical factors responsible for impingement, subluxation, and dislocation remain under-investigated relative to their burden of morbidity. This manuscript outlines a 15-year program of laboratory and clinical research undertaken to improve the scientific basis for understanding total hip impingement and dislocation. The broad theme has been to systematically evaluate the role of surgical factors, implant design factors, and patient factors in predisposing total hip constructs to impinge, sublux, and/or dislocate. Because this class of adverse biomechanical events had not lent itself well to study with existing approaches, it was necessary to develop (and validate) a series of new research methodologies, relying heavily on advanced finite element formulations. Specific areas of focus have included identifying the biomechanical challenges posed by dislocation-prone patient activities, quantifying design parameter effects and component surgical positioning effects for conventional metal-on-polyethylene implant constructs, and the impingement/dislocation behavior of non-conventional constructs, quantifying the stabilizing role of the hip capsule (and of surgical repairs of capsule defects), and systematically studying impingement and edge loading of hard-on-hard bearings, fracture of ceramic liners, confounding effects of patient obesity, and subluxation-mediated worsening of third body particle challenge. PMID:25328453

Brown, Thomas D; Elkins, Jacob M; Pedersen, Douglas R; Callaghan, John J

2014-01-01

356

Proximal Scaphoid Arthroplasty Using the Medial Femoral Trochlea Flap  

PubMed Central

Background The medial trochlea of the femur (medial femoral trochlea, MFT) provides a source of convex osteocartilaginous vascularized bone that has been demonstrated to have a similar contour to the proximal scaphoid. This provides a potential solution for difficult recalcitrant proximal pole scaphoid nonunions. Materials and Methods Sixteen consecutive patients who underwent MFT proximal scaphoid arthroplasty were reviewed. Follow-up data were recorded at a minimum of 6 months, with an average of 14 months. The results of this cohort were previously reported in detail but are summarized herein. Description of Technique The ability to reconstruct both bone and cartilage of the nonunion enables the surgeon to resect the nonunited proximal pole to prepare for scaphoid reconstruction. A segment of osteocartilaginous MFT is harvested in dimensions required by the scaphoid defect. The MFT segment is harvested on the transverse branch of the descending geniculate vessels. Fixation may be achieved with ease due to the size of the reconstructed segment. Results Computed tomography imaging demonstrated 15 of 16 reconstructed scaphoids achieving osseous union. Follow-up range of motion (ROM) of the wrist averaged 46.0° extension (range 28-80°) and 43.8° flexion (range 10-80°), which was similar to preoperative (average 45.7° extension and 43.0° flexion). Scapholunate angles remained unaffected (51.6° preoperatively and 48.6° postoperatively), indicating preservation of carpal relationships. Conclusions Vascularized MFT flaps provide a useful tool in the treatment of difficult proximal pole scaphoid nonunions. Early follow-up demonstrates high rate of achieving union with acceptable ROM and good pain relief. PMID:24436821

Higgins, James P.; Burger, Heinze K.

2013-01-01

357

Autologous bone plugs in unilateral total knee arthroplasty  

PubMed Central

Background: The purpose of this study was to compare blood loss, declines in hemoglobin (HgB) and hematocrit (HcT) levels, and required homologous transfusions for patients who either had the femoral intramedullary defect left open or filled with an autologous bone plug during total knee arthroplasty (TKA). We hereby present our results of autologous bone plugs in unilateral TKA. Materials and Methods: A retrospective chart review was performed on 55 patients diagnosed with osteoarthritis (OA) who had undergone unilateral TKA. Twenty six patients had the femoral defect filled with an autologous bone plug and 29 did not. Lateral releases and patella replacements were not performed. Drained blood was reinfused when appropriate. Results: Mean blood loss and mean blood reinfused were similar for the plugged (loss: 960.8 ± 417.3 ml; reinfused: 466.7 ± 435.9 mL) and unplugged groups (loss: 1065.9 ± 633.5 ml, P = 0.38; reinfused: 528.4 ± 464.8 ml, P = 0.61). Preoperative HgB (14.3 ± 1.4 g/dL, P = 0.93) and HcT levels (42.2 ± 4.6%, P = 0.85) were similar across plug conditions. HgB and HcT levels declined similarly for the plugged (2.7 ± 1.2 g/dl and 7.9 ± 4.0%) and unplugged groups (3.0 ± 0.9 g/dl, P = 0.16 and 9.0 ± 2.6%, P = 0.16), respectively. Of patients, one in the plugged group and none in the unplugged group required homologous transfusions (P = 0.5). Conclusion: The autologous bone plug does not appear to reduce the need for homologous blood transfusions following unilateral TKA. PMID:23682181

Protzman, Nicole M; Buck, Nicholas J; Weiss, Carl B

2013-01-01

358

Evolution of aggressive granulomatous periprosthetic lesions in cemented hip arthroplasties.  

PubMed

The authors analyzed the histologic findings from material retrieved during 17 revision operations from 15 patients who had cemented total hip arthroplasty or hemiarthroplasty. In 13 patients, the indication for revision was aseptic loosening. In four patients, technical error during implantation of the prostheses made revision necessary. The histologic pictures in the loosened and nonloosened prostheses were similar, characterized by the presence of a synovial-like membrane at the site corresponding to the hip joint cavity or abutting the implant, underneath which were found aggregates of histiocytes and foreign-body giant cells within a dense fibrous matrix. The main foreign material in all patients consisted of fine granules or larger cement particles. A few polyethylene fibers were also observed in some patients. Metal deposits were found in three patients with titanium alloy implants and extensive loosening. The most interesting aspect of this series was the opportunity it provided to study the progressive development of the synovial-like membrane and the first appearance of the cement granulomas in non-loosened cases. The first signs of the synovial membrane appeared 2.5 months postoperatively, whereas the first cement debris were observed as early as seven months after the implantation of the prosthesis. The hip joint newly formed membrane in the nonloosened cases did not differ histologically from that in the loosened cases. Because the histology of loosened and technically poorly placed nonloosened-prostheses are the same, the authors believe that the mechanism of failure associated with cell macrophage-mediated osteolysis may be the same. PMID:8131328

Korovessis, P; Repanti, M

1994-03-01

359

Distal femoral bone mineral density decreases following patellofemoral arthroplasty: 1-year follow-up study of 14 patients  

Microsoft Academic Search

BACKGROUND: The bone mineral density (BMD) of the distal femur decreases by 16-36% within one year after total knee arthroplasty (TKA) because of the femoral component's stress-shielding effect. The aim of this prospective study was to determine the quantitative change from the baseline BMD in the distal femur 1 year after patellofemoral arthroplasty using dual-energy X-ray absorptiometry (DXA). METHODS: Between

Hans-Peter W van Jonbergen; Kenneth Koster; Luc Labey; Bernardo Innocenti; Albert van Kampen

2010-01-01

360

A comparison of outcomes of cervical disc arthroplasty and fusion in everyday clinical practice: surgical and methodological aspects  

Microsoft Academic Search

Randomised controlled trials (RCTs) of cervical disc arthroplasty vs fusion generally show slightly more favourable results\\u000a for arthroplasty. However, RCTs in surgery often have limited external validity, since they involve a select group of patients\\u000a who fit very rigid admission criteria and who are prepared to subject themselves to randomisation. The aim of this study was\\u000a to examine whether the

Dieter Grob; Francois Porchet; Frank S. Kleinstück; Friederike Lattig; Dezsoe Jeszenszky; Andrea Luca; Urs Mutter; Anne F. Mannion

2010-01-01

361

Reverse shoulder arthroplasty as a salvage procedure for failed conventional shoulder replacement due to cuff failure—midterm results  

Microsoft Academic Search

Our goal was to evaluate the objective and subjective midterm outcome after revision of a failed shoulder arthroplasty with\\u000a a reverse design prosthesis. Twenty consecutive patients with 21 revisions of a primary shoulder arthroplasty using reverse\\u000a shoulder prosthesis Delta III® were followed up postoperatively for a mean of 46 months including clinical and radiological examination. Complications were\\u000a recorded and Constant score,

Matthias P. Flury; Philipp Frey; Joerg Goldhahn; Hans-Kaspar Schwyzer; Beat R. Simmen

2011-01-01

362

Observation of polychromatic gap solitons  

E-print Network

theoretically and observe experimentally poly- chromatic gap solitons generated by supercontinuum light-induced broadening and color separation to the simultaneous spatio-spectral localization of supercontinuum light. Kivshar, "Controlled generation and stee

363

Gap-Definable Counting Classes  

Microsoft Academic Search

The function class #P lacks an important closure property: it is not closed under subtraction.To remedy this problem, we introduce the function class GapP as a natural alternative to #P.GapP is the closure of #P under subtraction, and has all the other useful closure propertiesof #P as well. We show that most previously studied counting classes, including PP, C=P,and Mod

Stephen A. Fenner; Lance J. Fortnowt; Stuart A. Kurtz

1991-01-01

364

Eight electrode optical readout gap  

DOEpatents

A protective device for a plurality of electrical circuits includes a pluity of isolated electrodes forming a gap with a common electrode. An output signal, electrically isolated from the circuits being monitored, is obtained by a photosensor viewing the discharge gap through an optical window. Radioactive stabilization of discharge characteristics is provided for slowly changing voltages and carbon tipped dynamic starters provide desirable discharge characteristics for rapidly varying voltages. A hydrogen permeation barrier is provided on external surfaces of the device.

Boettcher, Gordon E. (Albuquerque, NM); Crain, Robert W. (Albuquerque, NM)

1985-01-01

365

Eight electrode optical readout gap  

DOEpatents

A protective device for a plurality of electrical circuits includes a plurality of isolated electrodes forming a gap with a common electrode. An output signal, electrically isolated from the circuits being monitored, is obtained by a photosensor viewing the discharge gap through an optical window. Radioactive stabilization of discharge characteristics is provided for slowly changing voltages and carbon tipped dynamic starters provide desirable discharge characteristics for rapidly varying voltages. A hydrogen permeation barrier is provided on external surfaces of the device.

Boettcher, G.E.; Crain, R.W.

1984-01-01

366

GRADE GAP/FUTURE GAP: ADDRESSING RACIAL DISPARITIES IN L&S INTRODUCTORY COURSES  

E-print Network

1 GRADE GAP/FUTURE GAP: ADDRESSING RACIAL DISPARITIES IN L&S INTRODUCTORY COURSES Report ........................................................................................................................................................................ 3 RECOMMENDATIONS: ELIMINATE THE GRADE GAP IN KEY INTRODUCTORY COURSES BY 2014............. 4.................................................................................................................................................. 5 THE GRADE GAP IN KEY INTRODUCTORY COURSES

Sheridan, Jennifer

367

Field induced gap infrared detector  

NASA Technical Reports Server (NTRS)

A tunable infrared detector which employs a vanishing band gap semimetal material provided with an induced band gap by a magnetic field to allow intrinsic semiconductor type infrared detection capabilities is disclosed. The semimetal material may thus operate as a semiconductor type detector with a wavelength sensitivity corresponding to the induced band gap in a preferred embodiment of a diode structure. Preferred semimetal materials include Hg(1-x)Cd(x)Te, x is less than 0.15, HgCdSe, BiSb, alpha-Sn, HgMgTe, HgMnTe, HgZnTe, HgMnSe, HgMgSe, and HgZnSe. The magnetic field induces a band gap in the semimetal material proportional to the strength of the magnetic field allowing tunable detection cutoff wavelengths. For an applied magnetic field from 5 to 10 tesla, the wavelength detection cutoff will be in the range of 20 to 50 micrometers for Hg(1-x)Cd(x)Te alloys with x about 0.15. A similar approach may also be employed to generate infrared energy in a desired band gap and then operating the structure in a light emitting diode or semiconductor laser type of configuration.

Elliott, C. Thomas (inventor)

1990-01-01

368

Direct band gap silicon allotropes.  

PubMed

Elemental silicon has a large impact on the economy of the modern world and is of fundamental importance in the technological field, particularly in solar cell industry. The great demand of society for new clean energy and the shortcomings of the current silicon solar cells are calling for new materials that can make full use of the solar power. In this paper, six metastable allotropes of silicon with direct or quasidirect band gaps of 0.39-1.25 eV are predicted by ab initio calculations at ambient pressure. Five of them possess band gaps within the optimal range for high converting efficiency from solar energy to electric power and also have better optical properties than the Si-I phase. These Si structures with different band gaps could be applied to multiple p-n junction photovoltaic modules. PMID:24971657

Wang, Qianqian; Xu, Bo; Sun, Jian; Liu, Hanyu; Zhao, Zhisheng; Yu, Dongli; Fan, Changzeng; He, Julong

2014-07-16

369

Brain responses to filled gaps  

PubMed Central

An unresolved issue in the study of sentence comprehension is whether the process of gap-filling is mediated by the construction of empty categories (traces), or whether the parser relates fillers directly to the associated verb’s argument structure. We conducted an event-related potentials (ERP) study that used the violation paradigm to examine the time course and spatial distribution of brain responses to ungrammatically filled gaps. The results indicate that the earliest brain response to the violation is an early left anterior negativity (eLAN). This ERP indexes an early phase of pure syntactic structure building, temporally preceding ERPs that reflect semantic integration and argument structure satisfaction. The finding is interpreted as evidence that gap-filling is mediated by structurally predicted empty categories, rather than directly by argument structure operations. PMID:16970985

Hestvik, Arild; Maxfield, Nathan; Schwartz, Richard G.; Shafer, Valerie

2007-01-01

370

Blood management strategies in primary and revision total knee arthroplasty for Jehovah's Witness patients.  

PubMed

Primary or revision total knee arthroplasties (TKAs) may be associated with a marked amount of intraoperative or postoperative blood loss that potentially may lead to the need for blood transfusions. However, Jehovah's Witnesses usually refuse blood transfusions because of their religious beliefs. This may create clinical or ethical challenges for the treating physicians. Therefore, following established blood management protocols specifically designed for these patients may be beneficial for the performance of safe and transfusion-free procedures with minimal complications. In this report, we provide an overview of various potential preoperative, intraoperative, and postoperative blood management measures that may be used for the care of Jehovah's Witnesses who undergo knee arthroplasty procedures. In addition, we review reported outcomes of primary and revision TKAs in these patients. PMID:23955185

Issa, Kimona; Banerjee, Samik; Rifai, Aiman; Kapadia, Bhaveen H; Harwin, Steven F; McInerney, Vincent K; Mont, Michael A

2013-12-01

371

Patient versus Provider Characteristics Impacting Hospital Lengths of Stay Following Total Knee or Hip Arthroplasty  

PubMed Central

Introduction This study aims to identify whether patient-level or provider-level characteristics are most influential on a patient’s length of stay in the acute care hospital. Materials and Methods A dataset containing a nationally representative sample of inpatient discharge abstracts was used. Multi-level linear regression models were used to evaluate the associations between patient- and provider-level characteristics on patients’ lengths of stay. Results The target population included 322,894 discharges with a primary procedure code for primary total knee arthroplasty and 193,553 discharges for total hip arthroplasty. The variables associated with the greatest increases in length of stay were a higher co-morbidity level among patient level attributes (+17.4%) and low surgeon volume among provider-level characteristics (+18.8%). Discussion Provider-level characteristics, particularly provider volume, had a greater impact on length of stay. PMID:21277159

Styron, Joseph F.; Koroukian, Siran; Klika, Alison; Barsoum, Wael K.

2010-01-01

372

Early Clinical and Radiographic Results of Minimally Invasive Anterior Approach Hip Arthroplasty  

PubMed Central

We present a retrospective review of the early results and complications in a series of 35 consecutive patients with 43 total hip arthroplasties performed through an anterior muscle sparing minimally invasive approach. We found the early complication rates and radiographic outcomes comparable to those reported from arthroplasties performed via traditional approaches. Complications included dislocation (2%), femur fracture (2%), greater trochanteric fracture (12%), postoperative periprosthetic intertrochanteric fracture (2%), femoral nerve palsy (5%), hematoma (2%), and postoperative iliopsoas avulsion (2%). Radiographic analysis revealed average cup anteversion of 19.6° ± 6.6, average cup abduction angle of 48.4° ± 7, stem varus of 0.9° ± 2, and a mean leg length discrepancy of 0.7?mm. The anterior approach to the hip is an attractive alternative to the more traditional approaches. Acceptable component placement with comparable complication rates is possible using a muscle sparing technique which may lead to faster overall recovery. PMID:24715984

Alexandrov, Tamara; Ahlmann, Elke R.; Menendez, Lawrence R.

2014-01-01

373

Early clinical and radiographic results of minimally invasive anterior approach hip arthroplasty.  

PubMed

We present a retrospective review of the early results and complications in a series of 35 consecutive patients with 43 total hip arthroplasties performed through an anterior muscle sparing minimally invasive approach. We found the early complication rates and radiographic outcomes comparable to those reported from arthroplasties performed via traditional approaches. Complications included dislocation (2%), femur fracture (2%), greater trochanteric fracture (12%), postoperative periprosthetic intertrochanteric fracture (2%), femoral nerve palsy (5%), hematoma (2%), and postoperative iliopsoas avulsion (2%). Radiographic analysis revealed average cup anteversion of 19.6° ± 6.6, average cup abduction angle of 48.4° ± 7, stem varus of 0.9° ± 2, and a mean leg length discrepancy of 0.7?mm. The anterior approach to the hip is an attractive alternative to the more traditional approaches. Acceptable component placement with comparable complication rates is possible using a muscle sparing technique which may lead to faster overall recovery. PMID:24715984

Alexandrov, Tamara; Ahlmann, Elke R; Menendez, Lawrence R

2014-01-01

374

The Impact of Blood Management on Length of Stay After Primary Total Knee Arthroplasty  

PubMed Central

The current study investigates the impact of patient factors, surgical factors, and blood management on postoperative length of stay (LOS) in 516 patients who underwent primary total knee arthroplasty. Age, gender, type of anticoagulation, but not body mass index (BMI) were found to be highly significant predictors of an increased LOS. Allogeneic transfusion and the number of allogeneic units significantly increased LOS, whereas donation and/or transfusion of autologous blood did not. Hemoglobin levels preoperatively until 48 hours postoperatively were negatively correlated with LOS. After adjusting for confounding factors through Poisson regression, age (p = 0.001) and allogeneic blood transfusion (p = 0.002) were the most significant determinants of LOS. Avoiding allogeneic blood plays an essential role in reducing the overall length of stay after primary total knee arthroplasty. PMID:24894715

Monsef, Jad B; Della Valle, Alejandro G; Mayman, David J; Marx, Robert G; Ranawat, Amar S; Boettner, Friedrich

2014-01-01

375

Do larger femoral heads improve the functional outcome in total hip arthroplasty?  

PubMed

Use of larger diameter femoral heads has been popularised in total hip arthroplasty (THA). Recent studies have implicated larger femoral heads in early failure. We evaluated what effect the size of the femoral head had on the early functional outcome in order to determine the optimal head size for the maximal functional outcome. There were 726 patients who underwent elective THA and were divided into 3 groups according to head size then compared with respect to functional outcome scores and dislocation rates. This study failed to show that increasing the size of the femoral head significantly improved the functional outcome at 1 year after total hip arthroplasty but that the use of a 36 mm or greater femoral head did reduce the dislocation rate. PMID:23891058

Allen, Charlotte L; Hooper, Gary J; Frampton, Christopher M A

2014-02-01

376

Kneeling is safe for patients implanted with medial-pivot total knee arthroplasty designs.  

PubMed

Nine ADVANCE (Wright Medical Technology, Arlington, TN)) Medial-Pivot (MP) and 9 ADVANCE Double-High total knee arthroplasties were analyzed under radiographic surveillance at standing, mid kneeling, and full kneeling. In vivo tibiofemoral contact positions were obtained using the 3- to 2-dimensional image registration technique. The contact in Double-High knee was always more posterior than that in the MP knee presumably because of the presence of the posterior cruciate ligament. The contact positions in both the designs moved anterior from standing to mid kneeling, moved posterior from mid kneeling to full kneeling, and remained within the intended articulation range of the implants. This study indicates that kneeling is safe in MP total knee arthroplasty even in the absence of a cam-post or posterior cruciate ligament. PMID:20541359

Barnes, C Lowry; Sharma, Adrija; Blaha, J David; Nambu, Satya N; Carroll, Michael E

2011-06-01

377

Thirty years of experience with alumina-on-alumina bearings in total hip arthroplasty.  

PubMed

Alumina-on-alumina bearings in total hip arthroplasty have been developed in an attempt to minimise debris and the occurrence of osteolytic lesions. The outstanding tribological properties of this bearing system are explained by low surface roughness, high hardness for major scratch resistance, and high wettability. Since the 1970s, technological improvements in the manufacturing process of alumina components together with a better understanding of Morse taper technology have provided a surgical grade material with high density, high purity and small grains. Published studies on the outcome of total hip arthroplasty performed with this new generation of implants showed high survivorship especially in young and active patients, with survival rates free of revision of 90.8% to 97.4% at ten years. However, concern remains over ceramic liner fracture and squeaking, which has been noted recently with increasing prevalence. This review will discuss the current knowledge on the use of alumina-on-alumina bearings. PMID:21191579

Hannouche, Didier; Zaoui, Amine; Zadegan, Frédéric; Sedel, Laurent; Nizard, Rémy

2011-02-01

378

Mortality following hip arthroplasty--inappropriate use of National Joint Registry (NJR) data.  

PubMed

Mortality following hip arthroplasty is affected by a large number of confounding variables each of which must be considered to enable valid interpretation. Relevant variables available from the 2011 NJR data set were included in the Cox model. Mortality rates in hip arthroplasty patients were lower than in the age-matched population across all hip types. Age at surgery, ASA grade, diagnosis, gender, provider type, hip type and lead surgeon grade all had a significant effect on mortality. Schemper's statistic showed that only 18.98% of the variation in mortality was explained by the variables available in the NJR data set. It is inappropriate to use NJR data to study an outcome affected by a multitude of confounding variables when these cannot be adequately accounted for in the available data set. PMID:24857335

Whitehouse, Sarah L; Bolland, Benjamin J R F; Howell, Jonathan R; Crawford, Ross W; Timperley, A John

2014-09-01

379

Thirty years of experience with alumina-on-alumina bearings in total hip arthroplasty  

PubMed Central

Alumina-on-alumina bearings in total hip arthroplasty have been developed in an attempt to minimise debris and the occurrence of osteolytic lesions. The outstanding tribological properties of this bearing system are explained by low surface roughness, high hardness for major scratch resistance, and high wettability. Since the 1970s, technological improvements in the manufacturing process of alumina components together with a better understanding of Morse taper technology have provided a surgical grade material with high density, high purity and small grains. Published studies on the outcome of total hip arthroplasty performed with this new generation of implants showed high survivorship especially in young and active patients, with survival rates free of revision of 90.8% to 97.4% at ten years. However, concern remains over ceramic liner fracture and squeaking, which has been noted recently with increasing prevalence. This review will discuss the current knowledge on the use of alumina-on-alumina bearings. PMID:21191579

Zaoui, Amine; Zadegan, Frederic; Sedel, Laurent; Nizard, Remy

2010-01-01

380

Thirty-day readmission following total hip and knee arthroplasty - a preliminary single institution predictive model.  

PubMed

We sought to identify demographic or care process variables associated with increased 30-day readmission within the total hip and knee arthroplasty patient population. Using this information, we generated a model to predict 30-day readmission risk following total hip and knee arthroplasty procedures. Longer index length of stay, discharge disposition to a nursing facility, blood transfusion, general anesthesia, anemia, anticoagulation status prior to index admission, and Charlson Comorbidity Index greater than 2 were identified as independent risk factors for readmission. Care process factors during the hospital stay appear to have a large predictive value for 30-day readmission. Specific comorbidities and patient demographic factors showed less significance. The predictive nomogram constructed for primary total joint readmission had a bootstrap-corrected concordance statistic of 0.76. PMID:24703364

Mesko, Nathan W; Bachmann, Keith R; Kovacevic, David; LoGrasso, Mary E; O'Rourke, Colin; Froimson, Mark I

2014-08-01

381

The results of 479 thumb carpometacarpal joint replacements reported in the Norwegian Arthroplasty Register.  

PubMed

In this study we report the results of thumb carpometacarpal (CMC) joint replacements in the Norwegian population over a 17-year period. In total, 479 primary replacements performed from 1994 to 2011 were identified in the Norwegian Arthroplasty Register. Implant survival and risk of revision were analyzed using Cox regression analyses. Four different implant designs were compared and time trends were analyzed. The overall 5 and 10 year survivals were 91% and 90%, respectively. The newer metal total arthroplasties did not outperform the older silicone and mono-block implants. At 5 years, the implant survival ranged from 90% to 94% for the different implant brands. Gender, age, and diagnosis did not influence the risk of revision. The incidence of thumb CMC joint replacement did not change during the study period. Despite relatively satisfactory implant survivorship in our register study, current evidence does not support widespread implementation of thumb CMC replacements. PMID:24784114

Krukhaug, Y; Lie, S A; Havelin, L I; Furnes, O; Hove, L M; Hallan, G

2014-10-01

382

A nomogram to predict major complications after hip and knee arthroplasty.  

PubMed

We aimed to develop a nomogram for risk stratification of major postoperative complications in hip and knee arthroplasty based on preoperative and intraoperative variables, and assessed whether this tool would have better predictive performance compared to the Surgical Apgar Score (SAS). Logistic regression analysis was performed to develop a nomogram. Discrimination and calibration were assessed. Net reclassification improvement (NRI) was used to compare to the SAS. All variables were found to be statistically significant predictors of post-operative complications except race and lowest heart rate. The concordance index was 0.76 with good calibration. Compared to the SAS, the NRI was 71.5% overall. We developed a clinical prediction tool, the Morbidity and Mortality Acute Predictor for arthroplasty (arthro-MAP) that might be useful for postoperative risk stratification. PMID:24793891

Wuerz, Thomas H; Kent, David M; Malchau, Henrik; Rubash, Harry E

2014-07-01

383

Use of spontaneous electromyography during revision and complex total hip arthroplasty.  

PubMed

Intraoperative peripheral nerve injury is a serious potential complication of orthopaedic surgery and various intraoperative neurophysiologic monitoring techniques have been used to avoid this complication. Although somatosensory evoked potentials have been used effectively in spinal surgery, the efficacy of this technique has not been demonstrated in total hip arthroplasty. Spontaneous electromyography is a promising, alternative nerve monitoring technique. This technique was used in 44 consecutive revision and complex hip arthroplasty procedures. Five cases demonstrated sustained electromyography activity during surgery that subsided after retractors were removed and the limb brought into an anatomic position. In none of these five cases was there any evidence of clinical neurologic dysfunction after surgery. One patient developed causalgia without any motor deficit, but had no sustained electromyography activity during surgery. Spontaneous electromyography provides real-time monitoring of nerve function that allows immediate corrective action to be taken before nerve injury occurs. PMID:8648319

Sutherland, C J; Miller, D H; Owen, J H

1996-02-01

384

Conversion of fused hip to total hip arthroplasty with presurgical and postsurgical gait studies.  

PubMed

This case study presents a subject with a fused hip converted to total hip arthroplasty. Kinematic gait analysis was conducted on 3 occasions, presurgery, 4 months postsurgery, and 2.5 years postsurgery. Presurgery data showed decreased cadence and shorter step length; sound limb possessed increased hip, knee range of motion (ROM), and increased knee flexion during stance; the affected limb had minimal hip motion and normal knee ROM with abnormal pattern. At 4 months postsurgery, the sound limb showed decreased step length, whereas the affected limb showed increased knee extension during stance and increased hip ROM. Data obtained at 2.5 years postsurgery indicated decreased cadence and speed and increased ROM in both limbs. The total hip arthroplasty had provided relief of chronic back and affected hip pain and improved mobility. Gait-specific training is recommended. PMID:21944370

Bonin, Stephanie J; Eltoukhy, Moataz A; Hodge, W Andrew; Asfour, Shihab S

2012-03-01

385

Biochemical markers of bone turnover in aseptic loosening in hip arthroplasty  

PubMed Central

The aim of this study was to determine the diagnostic value of systemic biochemical markers of bone turnover in aseptic loosening in hip arthroplasty, namely the urine levels of three bone resorption peptides – crosslinked n-telopeptides (NTX), c-telopeptides (CTX I) and deoxypyridinoline (DPD). We compared 52 patients with surgically proven component loosening with 52 patients without clinical or radiological signs of endoprosthetic loosening and 52 healthy individuals. All three markers were measured using commercially available enzyme-linked immunoassays. We found significantly increased levels of DPD in the loosening group (p?arthroplasty but CTX I and NTX have no predictive value in this context. PMID:18084760

Gotterbarm, Tobias; Jung, Martin; Schneider, Ulrich; Heisel, Christian

2007-01-01

386

What do we know about taper corrosion in total hip arthroplasty?  

PubMed

Mechanically assisted crevice corrosion (MACC) at metal/metal modular junctions in which at least one of the components is fabricated from cobalt-chromium alloy, has reemerged as a potential clinically significant complication in total hip arthroplasty. The clinical manifestation of MACC may include the development of an adverse local tissue reaction (ALTR), similar to what has been described in association with metal-on-metal bearing total hip and resurfacing arthroplasty. The clinical presentation of MACC-associated ALTRs may include pain and possibly late recurrent dislocations. Abnormal metal artifact reduction sequence magnetic resonance images and elevated serum metal levels (cobalt elevations out of proportion to chromium elevations) can be helpful in the diagnosis of these MACC-associated ALTRs. PMID:24655613

Jacobs, J J; Cooper, H J; Urban, R M; Wixson, R L; Della Valle, C J

2014-04-01

387

Tobacco use may be associated with increased revision and complication rates following total hip arthroplasty.  

PubMed

The purpose of this study was to compare the clinical outcomes of total hip arthroplasty in patients who were smokers to patients who were non-smokers. All total hip arthroplasties performed between 2007 and 2009 were reviewed to identify patients who indicated tobacco use. There were 110 smokers who were matched in a 1:2 ratio to 220 non-smoking patients. At a mean follow-up of 51 months (range, 24 to 72 months), smokers had an overall significantly lower survivorship of 92% (n = 9 revisions), compared to 99% (n = 2 revisions) in non-smokers. In addition, there were five complications in smokers (one pneumonia, three superficial infections, and one deep peroneal nerve palsy) compared to none in non-smokers. These results indicate that patients who smoke had higher overall revisions and postoperative complications. PMID:24090663

Kapadia, Bhaveen H; Issa, Kimona; Pivec, Robert; Bonutti, Peter M; Mont, Michael A

2014-04-01

388

Nontraumatic Fracture of the Femoral Condylar Prosthesis in a Total Knee Arthroplasty Leading to Mechanical Failure  

PubMed Central

This paper reports a case of fatigue fracture of the femoral component in a cruciate-retaining cemented total knee arthroplasty (TKA). A 64-year-old man had undergone a primary TKA for osteoarthritis 10 years previously at another institution using the PFC-Sigma prosthesis. The patient recovered fully and was back to his regular activities. He presented with a history of sudden onset pain and locking of the left knee since the preceding three months. There was no history of trauma, and the patient was mobilizing with difficulty using crutches. Radiographs revealed fracture of the posterior condyle of the femoral prosthesis. Revision surgery was performed as an elective procedure revealing the broken prosthesis. The TC3RP-PFC revision prosthesis was used with a medial parapatellar approach. The patient recovered fully without any squeal. Mechanical failure of the knee arthroplasty prosthesis is rare, and nontraumatic fracture of the femoral metallic component has not been reported before. PMID:24587928

Swamy, Girish N.; Quah, Conal; Bagouri, Elmunzar; Badhe, Nitin P.

2014-01-01

389

Minority Gaps Smaller in Some Pentagon Schools. The Achievement Gap.  

ERIC Educational Resources Information Center

This third in a four-part series on why academic achievement gaps exist explains how U.S. Department of Defense schools for children of military families offer lessons on how to raise academic achievement among minority students. Minority students in these schools do better than their counterparts almost anywhere in the United States on…

Viadero, Debra

2000-01-01

390

Accuracy of haptic assessment of patellar symmetry in total knee arthroplasty 1 1 No benefits or funds were received in support of the study  

Microsoft Academic Search

Resection resulting in asymmetrically thick patellar arthroplasty in knee arthroplasty may lead to increased compression forces, wear, fracture, or loss of quadriceps power. Assessing the cut patella between the thumb and forefinger (haptic assessment) represents a convenient way to recognize asymmetry. In 2 test series, 8 orthopedic surgeons evaluated 24 precut solid foam patellae of varying asymmetric thickness by feeling

James K DeOrio; John P Peden

2004-01-01

391

Closing the Salary Gap Noreen Rossi  

E-print Network

Closing the Salary Gap Noreen Rossi Dawn Misra #12;Overview · Evidence of salary gap for women practices · Practices to avoid · Future directions #12;Evidence of salary gap for women · Academics://www.forbes.com/sites/katetaylor/2012/06/13/eve n-women-doctors-cant-escape-the-pay-gap/ #12;Starting salaries of new physicians reveal

Finley Jr., Russell L.

392

Long-term results of hip arthroplasty in ambulatory patients with cerebral palsy  

Microsoft Academic Search

Osteoarthritis (OA) secondary to dislocation and dysplasia is a common problem in patients with cerebral palsy. The purpose\\u000a of this study was to evaluate the results of total hip replacement (THR) in ambulatory patients with cerebral palsy. Eighteen\\u000a total hip arthroplasties were performed in 16 ambulatory patients with cerebral palsy. The patient's mean age at surgery was\\u000a 42?±?8 years (range 32–58

Kerstin Schroeder; Christian Hauck; Bernd Wiedenhöfer; Frank Braatz; Peter R. Aldinger

2010-01-01

393

Small-Dose Ketamine Infusion Improves Postoperative Analgesia and Rehabilitation After Total Knee Arthroplasty  

Microsoft Academic Search

We designed this study to evaluate the effect of small- dose IV ketamine in combination with continuous fem- oral nerve block on postoperative pain and rehabilita- tion after total knee arthroplasty. Continuous femoral nerve block was started with 0.3 mL\\/kg of 0.75% ropi- vacaine before surgery and continued in the surgical ward for 48 h with 0.2% ropivacaine at a

Marcel Chauvin; Bertrand Du Manoir; Mathieu Langlois; Daniel I. Sessler; Dominique Fletcher

2005-01-01

394

Electrical stimulation-induced contraction to reduce blood stasis during arthroplasty  

Microsoft Academic Search

Deep venous thrombosis and subsequent pulmonary embolism due to venous pooling\\/stasis commonly occur in patients during hip and\\/or knee arthroplasty (i.e., replacement). This problem may be alleviated by using techniques to promote lower limb blood flow. Electrical stimulation-induced contractions have been shown to activate the skeletal muscle pump, promote limb blood flow, and may be effective for reducing venous pooling\\/stasis

Pouran D. Faghri; H. F. Pompe Van Meerdervort; Roger M. Glaser; Stephen F. Figoni

1997-01-01

395

[Ten errors to avoid while dealing with infected total joint arthroplasties].  

PubMed

Infections after total joint arthroplasty are rare but come with severe consequences. Timely, adequate and standardized treatment beginning at the onset of symptoms will have a major impact on the handling of this dreaded complication. In absences of clear guidelines, errors are often committed, with occasionally severe consequences for the patient. In this article, the 10 most frequent errors starting with diagnostics till antibiotic and surgical treatment will be discussed. PMID:23346750

Borens, Olivier; Tissot, Christophe; Delaloye, Jean-Romain; Trampuz, Andrej

2012-12-19

396

Correlation between preoperative and postoperative knee kinematics in total knee arthroplasty using cruciate retaining designs  

Microsoft Academic Search

The authors evaluated the relationships between preoperative and postoperative kinematics in 50 osteoarthritic knees scheduled\\u000a for cruciate retaining total knee arthroplasty with regards to posterior femoral roll back and external femoral rotation using\\u000a a navigation system from 10° to 120° of knee flexion. Although posterior femoral roll back was maintained, external femoral\\u000a rotation was significantly decreased compared to those of

Jong Keun Seon; Ju Kwon Park; Mun Su Jeong; Woo Bin Jung; Kyung Soon Park; Taek Rim Yoon; Eun Kyoo Song

2011-01-01

397

Digital subtraction arthrography in preoperative evaluation of painful total hip arthroplasty  

Microsoft Academic Search

Objective. The objective of this clinical study was to define the diagnostic value of plain radiography, digital subtraction arthrography\\u000a and two-phase bone scintigraphy in patients with clinically loose or infected hip prostheses. Design. Digital subtraction arthrograms, scintigrams and plain radiographs of 70 consecutive patients who underwent revision hip arthroplasty\\u000a were scored individually and in masked fashion for the presence or

A. Z. Ginai; F. C. van Biezen; P. A. M. Kint; H. Y. Oei; W. C. J. Hop

1996-01-01

398

Bilateral femoral neck stress fractures following total knee arthroplasty: a case report and review of literature  

Microsoft Academic Search

Stress fracture of the femoral neck following total knee arthroplasty (TKA) is an uncommon complication with only 20 cases\\u000a having been described in English literature so far. Stress fractures of femoral neck occurring simultaneously on both sides\\u000a following a bilateral total knee replacement is an exceptional occurrence, which to the best of our knowledge, has not been\\u000a described previously. We

Amite Pankaj; Rajesh Malhotra; Vivek Logani; Surya Bhan

2007-01-01

399

Primary total hip arthroplasty with a cementless porous-coated anatomic total hip prosthesis  

Microsoft Academic Search

We performed a prospective study in 108 consecutive patients (116 hips) who were followed for a minimum of 10 years (10–12 years) after primary total hip arthroplasty using an uncemented porous-coated anatomic (PCA) hip prosthesis. The average age of the patients at operation was 48.4 years (range, 19–85 years), and the diagnosis was avascular necrosis of the femoral head in

Young-Hoo Kim; Jun-Shik Kim; Soon-Ho Cho

1999-01-01

400

Degenerative changes of the deltoid muscle have impact on clinical outcome after reversed total shoulder arthroplasty  

Microsoft Academic Search

Introduction  Despite a high complication rate, subjective and objective results of reversed shoulder arthroplasty for severe rotator cuff\\u000a lesions associated with osteoarthritis, fracture sequelae, or revision of hemiarthroplasty are favorable. However, whether\\u000a the changes in biomechanics of the joint may lead to structural changes in the remaining rotator cuff and the deltoid muscle,\\u000a and may thereby alter the clinical result, has

Stefan H. GreinerDavid; David A. Back; Sebastian Herrmann; Carsten Perka; Patrick Asbach

2010-01-01

401

Effect of Pamidronate on Excretion of Pyridinium Crosslinks of Collagen After Total Hip Arthroplasty  

Microsoft Academic Search

Periprosthetic bone loss is an important factor that limits implant survival after total hip arthroplasty (THA). In a randomized trial we previously reported that pamidronate therapy prevented periprosthetic bone loss and decreased urinary excretion of N-telopeptide collagen cross-links over the first 6 months after THA, but had no apparent effect on free deoxypyridinoline excretion (J Bone Miner Res 2001; 16:556–564).

J. Mark Wilkinson; Brendan Jackson; Richard Eastell

2003-01-01

402

Quantitative gait analysis after bilateral total knee arthroplasty with two different systems within each subject  

Microsoft Academic Search

The functional behavior of two kinematically different knee arthroplasty systems within each subject was studied by gait analysis (three-dimensional kinematics, kinetics, dynamic electromyography) in five elderly patients, 2 to 5 years after bilateral surgery. Clinical results were good, yet gait velocity was reduced (range, 0.57–1.1 m\\/s), with a shortened stride length and a decreased duration of single-limb stance in all

Inès A. Kramers-de Quervain; Edgar Stüssi; Roland Müller; Tomas Drobny; Urs Munzinger; Norbert Gschwend

1997-01-01

403

Comparison of tibial rotation in fixed and mobile bearing total knee arthroplasty using computer navigation  

Microsoft Academic Search

Tibial rotation is an important aspect of knee function and can be altered after total knee arthroplasty (TKA). These alterations\\u000a include decreased internal rotation with knee flexion as compared to the normal state and paradoxical external rotation with\\u000a flexion. Mobile bearing total knee prostheses may allow greater unconstrained tibial rotation. I compared tibial rotation\\u000a after fixed bearing or mobile bearing

James B. Stiehl

2009-01-01

404

Thirty years of experience with alumina-on-alumina bearings in total hip arthroplasty  

Microsoft Academic Search

Alumina-on-alumina bearings in total hip arthroplasty have been developed in an attempt to minimise debris and the occurrence\\u000a of osteolytic lesions. The outstanding tribological properties of this bearing system are explained by low surface roughness,\\u000a high hardness for major scratch resistance, and high wettability. Since the 1970s, technological improvements in the manufacturing\\u000a process of alumina components together with a better

Didier Hannouche; Amine Zaoui; Frédéric Zadegan; Laurent Sedel; Rémy Nizard

2011-01-01

405

Arthrographic examination of the pseudocapsule of the hip after posterior dislocation of total hip arthroplasty  

Microsoft Academic Search

We examined the pseudocapsule in ten patients with posterior dislocation after total hip arthroplasty (THA) using arthrography\\u000a to investigate the relationship between dislocation and the state of the pseudocapsule. The pattern of contrast medium pooling\\u000a demonstrated on tangential views was evaluated. In five patients with early dislocation arthrography showed leakage indicating\\u000a lack of pseudocapsule whereas there was no leakage in

H. Miki; K. Masuhara

2000-01-01

406

Asymmetrical total knee arthroplasty does not improve patella tracking: a study without patella resurfacing  

Microsoft Academic Search

It is often suggested that patella tracking after total knee arthroplasty (TKA) with an asymmetrical patella groove is more\\u000a physiological than with a symmetrical patella groove. Therefore, this study tried to address two questions: what is the effect\\u000a of TKA on patella tracking, and is patella tracking after asymmetrical TKA more physiological than patella tracking after\\u000a symmetrical TKA? The patellar

Marco Barink; Huub Meijerink; Nico Verdonschot; Albert van Kampen; Maarten de Waal Malefijt

2007-01-01

407

Abductor weakness and stresses around acetabular components of total hip arthroplasty: a finite element analysis  

Microsoft Academic Search

Abductor weakness, and the resulting Trendelenburg gait, after total hip arthroplasty is believed to be associated with a\\u000a poor long-term outcome. We have constructed a two-dimensional finite element analysis using load cases to mimic this abductor\\u000a weakness. The finite element analysis demonstrates slightly increased stresses, particularly at the bone-cement interface\\u000a in the DeLee-Charnley zone I, which does not seem sufficient

A. G. Sutherland; S. D’Arcy; D Smart; G. P. Ashcroft

1999-01-01

408

Ten-year Results of an Inset Biconvex Patella Prosthesis in Primary Knee Arthroplasty  

Microsoft Academic Search

The inset biconvex patella component is an alternative form of patella resurfacing in knee arthroplasty. We retrospectively\\u000a reviewed 433 patients in whom 521 patella prostheses were implanted before April 1997 to determine survivorship, factors associated\\u000a with failure of the implant, incidence of anterior knee pain, and factors that may be associated with the latter. We had clinical\\u000a results for 204

Sani Erak; Vaishnav Rajgopal; Steven J. MacDonald; Richard W. McCalden; Robert B. Bourne

2009-01-01

409

Synchronisation of tibial rotational alignment with femoral component in total knee arthroplasty  

Microsoft Academic Search

The rotational axis of the tibial component in total knee arthroplasty described by Insall is generally accepted, but rotational\\u000a mismatch between the femoral and the tibial components can occur because the alignment of each component is determined separately.\\u000a We developed a connecting instrument to synchronise the axis of the tibia to the axis of the femur. We compared the rotational

Dong-Hoon Lee; Jai-Gon Seo; Young-Wan Moon

2008-01-01

410

Accuracy of side-cutting implantation instruments for total knee arthroplasty  

Microsoft Academic Search

A new generation of implantation instruments were developed for quadriceps sparing surgical approaches during total knee arthroplasty\\u000a (TKA). There is little information on the accuracy of the bone cuts performed with the side-cutting technique. A total of\\u000a 100 patients were randomized to undergo computer-assisted TKA or non-navigated TKA using a mini-subvastus surgical approach\\u000a and side-cutting implant instrumentation. The radiographic parameters,

Arno Martin; Mitchell B. Sheinkop; Mary M. Langhenry; Christian Oelsch; Mark Widemschek; Archibald von Strempel

2009-01-01

411

Partial revision knee arthroplasty with retention of well-fixed components  

Microsoft Academic Search

Retention of well-fixed and well-aligned component is a technically easier option compared to complete revision in a noninfected\\u000a revision knee arthroplasty. However, it is very often difficult to decide the right treatment in a particular clinical scenario.\\u000a In this study, we reviewed the available literature with regard to the role and indications of partial revision, advantages\\u000a and disadvantages of partial

Senthil Nathan Sambandam; Arif Gul; Issada Thongtrangan; Vartharaj Mounaswamy

2009-01-01

412

International multi-centre survivorship analysis of mobile bearing total knee arthroplasty  

Microsoft Academic Search

We retrospectively reviewed the experience of a large international multi-centre study of primary total knee arthroplasty with mobile bearing design and modifications of the tibial component to allow for bicruciate preservation, posterior cruciate retention, or sacrifice. Twenty-seven surgeons performed 4,743 total knee replacements between 1981 and 1997. Implants inserted were 324 that retained both cruciate ligaments, 2,165 that retained the

James B. Stiehl; Karel J. Hamelynck; Paul E. Voorhorst

2006-01-01

413

Patient-perceived outcome measures following unicompartmental knee arthroplasty with mini-incision  

Microsoft Academic Search

We reviewed 150 patients (183 knees) who underwent mini-incision unicompartmental knee arthroplasty (Oxford). Mean age was 71.5 (36–92) years. Review was conducted at least 12 months following surgery. To assess results, we used the Oxford knee questionnaire, modified Grimby score, return to sport and work, knee “normality” and patient general health. The mean Oxford knee score was 22.17 (range 12–54).

I. Jahromi; N. P. Walton; P. J. Dobson; P. L. Lewis; D. G. Campbell

2004-01-01

414

Failure of metal-backed patellar components after total knee arthroplasty  

Microsoft Academic Search

All revision total knee arthroplasties for failure of a metal-backed patellar component during a 4-year period were reviewed. Twenty-five revisions, representing six designs, were performed in 24 patients. The failure mode included wear or fragmentation of the patellar polyethylene in 20 knees, polyethylene separation from the metal baseplate in 3, and metal peg-baseplate fracture in 2. Time to revision averaged

DG Lewallen; JA Rand

1995-01-01

415

Total Knee Arthroplasty With 4.4 mm of Tibial Polyethylene  

Microsoft Academic Search

Three hundred eighty-seven one-piece, 8-mm tibial components were implanted in 313 patients. All tibial prostheses were manufactured with 4.4 mm of polyethylene. From this group, 116 patients underwent simultaneous bilateral total knee arthroplasty with an 8-mm tibial component on one side and a tibial component with at least 6.4 mm of polyethylene on the other side. Follow-up averaged 11.8 years.

John B. Meding; Jennifer T. Wing; Merrill A. Ritter

2010-01-01

416

SPINAL ARTHROPLASTY: INDICATIONS AND EARLY RESULTS. WHAT WILL THE FUTURE HOLD?  

Microsoft Academic Search

Total joint replacement for end-stage arthritis of the hip and knee has revolutionized the field of orthopaedic surgery. Both primary total hip and knee replacement have resulted in high rates of patient satisfaction and surgeons and patients have become accustomed to excellent long-term results. Spine surgeons and industry are now attempting to achieve similar results with spinal arthroplasty, i.e. total

RAJIV K. SETHI; KIRKHAM B. WOOD; JENNIFER DALEY; JAMES H. HERNDON

417

Prospective relation between catastrophizing and residual pain following knee arthroplasty: Two-year follow-up  

PubMed Central

BACKGROUND: Pain is the primary indication for both primary and revision total knee arthroplasty (TKA); however, most arthroplasty outcome measures do not take pain into account. OBJECTIVE: To document the prospective pain experience following TKA, with subjective pain-specific questionnaires to determine if comorbidities, preoperative pain or preoperative pain catastrophizing scores are predictive of long-term pain outcomes. METHODS: Fifty-five patients with a primary diagnosis of osteoarthritis of the knee, who were scheduled to undergo TKA, were asked to fill out the McGill Pain Questionnaire (MPQ) and the Pain Catastrophizing Scale (PCS) preoperatively and at three, 12 and 24 months follow-up. Comorbidities were extracted from the Queen Elizabeth II Health Sciences Centre health information system. RESULTS: The overall response rate (return of completed questionnaires) was 84%. There was a significant decrease in the MPQ scores (P<0.05) postoperatively. PCS scores did not change over time. Receiver operating characteristic curves revealed the number of comorbidities per patient predicted the presence of pain postoperatively, as documented by the numerical rating subscale of the MPQ at 24 months (P<0.05). Receiver operating characteristic curves for pre-operative PCS and rumination subscale scores predicted the presence of pain, as measured by the Pain Rating Index subscale of the MPQ at 24 months (P<0.05). Preoperative PCS scores and comorbidities were significantly higher in the persistent pain group (P<0.05). CONCLUSIONS: The number of comorbidities predicted the presence of pain at 24 months follow-up and, for the first time, preoperative PCS scores were shown to predict chronic postoperative pain. This may enable the identification of knee arthroplasty patients at risk for persistent postoperative pain, thus allowing for efficient administration of preoperative interventions to improve arthroplasty outcomes. PMID:18719716

Forsythe, Michael E; Dunbar, Michael J; Hennigar, Allan W; Sullivan, Michael JL; Gross, Michael

2008-01-01

418

Preoperative Function and Gender Predict Pattern of Functional Recovery After Hip and Knee Arthroplasty  

Microsoft Academic Search

Gender, preoperative function, and other variables were explored as predictors of recovery after total hip and knee arthroplasty. One hundred fifty-two subjects (63.8 ± 10.2 years) were repeatedly assessed in the first 4 postoperative months. Average recovery curves for the Western Ontario and McMaster Universities Osteoarthritis Index, 6-minute walk test, and timed up and go test were characterized using hierarchical

Deborah M. Kennedy; Steven E. Hanna; Paul W. Stratford; Jean Wessel; Jeffrey D. Gollish

2006-01-01

419

High medium-term survivorship and durability of Zweymüller-Plus total hip arthroplasty  

Microsoft Academic Search

Background and purpose  The Zweymüller-Plus system (SL-Plus stem, Bicon-Plus threaded cup) for primary total hip arthroplasty (THA) was introduced\\u000a in 1993, as a successor of the Alloclassic THA with a few modifications in the conical stem shape and a new biconical threaded\\u000a cup with a spherical shape. The medium-term performance of this system is not well established. To better understand the

Panagiotis Korovessis; Thomas Repantis; Andreas Zafiropoulos

2011-01-01

420

PEEK (Polyether-ether-ketone) Based Cervical Total Disc Arthroplasty: Contact Stress and Lubrication Analysis  

PubMed Central

This paper presents a theoretical analysis of the maximum contact stress and the lubrication regimes for PEEK (Polyether-ether-ketone) based self-mating cervical total disc arthroplasty. The NuNec® cervical disc arthroplasty system was chosen as the study object, which was then analytically modelled as a ball on socket joint. A non-adhesion Hertzian contact model and elastohydrodynamic lubrication theory were used to predict the maximum contact stress and the minimum film thickness, respectively. The peak contact stress and the minimum film thickness between the bearing surfaces were then determined, as the radial clearance or lubricant was varied. The obtained results show that under 150 N loading, the peak contact stress was in the range 5.9 – 32.1 MPa, well below the yield and fatigue strength of PEEK; the calculated minimum film thickness ranged from 0 to 0.042 µm and the corresponding lambda ratio range was from 0 to 0.052. This indicates that the PEEK based cervical disc arthroplasty will operate under a boundary lubrication regime, within the natural angular velocity range of the cervical spine. PMID:22670159

Xin, H; Shepherd, DET; Dearn, KD

2012-01-01

421

The relative safety of one-stage bilateral total knee arthroplasty  

PubMed Central

Patients with osteoarthritis of the knee often require bilateral knee replacement before fulfilling their full ambulatory potential. Despite extensive research there is considerable debate about the risks of performing simultaneous bilateral knee replacements under the same anaesthetic. Our aim was to compare the relative short-term morbidity of one-stage bilateral with unilateral total knee arthroplasty in a retrospective, consecutive cohort of patients. Seventy-two bilateral knee replacements were case-matched for age and gender with 144 unilateral knees. One-stage bilateral arthroplasty was associated with increased morbidity with respect to wound (6.0 vs 0.7%; p?=?0.003) and deep prosthetic (3.5% vs 0.7 %; p?=?0.02) infections, cardiac complications (3.5% vs 0.7%; p?=?0.04) and chest infections (7.0% vs 1.4%; p?=?0.04). No differences were observed in the mortality rates (p?=?0.30) and risk of thrombo-embolism (p?=?0.70). We conclude that one-stage bilateral total knee arthroplasty is associated with increased morbidity compared with unilateral knee replacement. PMID:17874240

Luscombe, J. C.; Abudu, A.; Carter, S. R.

2007-01-01

422

Results of infected total knee arthroplasty treated with arthroscopic debridement and continuous antibiotic irrigation system  

PubMed Central

Background: Arthroscopic debridement with continuous irrigation system was used with success in treating infective arthritis. We evaluated the effectiveness of arthroscopic debridement coupled with antibiotic continuous irrigation system in acute presentation of late infected total knee arthroplasty. Materials and Methods: We performed a retrospective review of medical record of patients with acute presentation of late infected total knee arthroplasty who were treated by arthroscopic debridement coupled with continuous postoperative antibiotic irrigation system. Results: Seventeen patients were included in our study. 15 (88%) patients preserved their total knee prosthesis at mean of followup of 27.5 months (range, 14-28 months). Two (12%) patients failed arthroscopic protocol and finally needed two stages revision. Our study showed an 88% prosthesis retention rate in patients with acute presentation of late prosthetic knee infection. No complication was associated with use of antibiotic irrigation system. Conclusion: Arthroscopic debridement combined with continuous antibiotic irrigation and suction is an effective treatment for patients with acute presentation of late infected total knee arthroplasty. PMID:23533105

Liu, Che-Wei; Kuo, Chun-Lin; Chuang, Shih-Youeng; Chang, Jen-Huei; Wu, Chia-Chun; Tsai, Tsung-Ying; Lin, Leou-Chyr

2013-01-01

423

Effect of clearance on cartilage tribology in hip hemi-arthroplasty.  

PubMed

Hemi-arthroplasty of the hip (an artificial femoral head articulating against the natural acetabulum) is used to treat fractured necks of femur; however, there is evidence that articulation causes erosion of the cartilage, resulting in pain for the patient. Parameters that may influence this cartilage erosion include head material and roughness, clearance between the head and acetabulum and activity levels of the patient. This study has assessed the effect of clearance of hemi-arthroplasty articulations on the contact stress, friction and cartilage deformation in an in vitro tribological simulation of the hemi-arthroplasty joint that applied dynamic loads and motion. It has been demonstrated that peak contact stress increased from 5.6 to 10.6 MPa as radial clearance increased from small (<0.6 mm) to extra-large (>1.8 mm). In all samples, friction factor increased with time and was significantly less with extra-large clearances compared to small (<0.6 mm), medium (0.6-1.2 mm) and large (1.2-1.8 mm) clearances. The cartilage deformation observed was significantly greater in acetabulum samples paired to give small or extra-large clearances compared to those with medium or large clearances. PMID:24043224

Lizhang, Jia; Taylor, Simon D; Jin, Zhongmin; Fisher, John; Williams, Sophie

2013-12-01

424

P-Selectin: An Unpredicted Factor for Deep Vein Thrombosis after Total Hip Arthroplasty  

PubMed Central

Introduction. Deep vein thrombosis (DVT) is a severe complication after total hip arthroplasty (THA). It leads to acute pulmonary embolism, a life-threatening disease. P-selectin is a 140-kDa transmembrane glycoprotein. Elevated P-selectin was associated with 1.7-fold increase in the risk of venous thrombosis. Materials and Methods. To confirm the association, a total of 91 subjects who received primary total hip arthroplasty using lateral approach performed by one skilled orthopedic surgeon were studied. All the patients were consecutively enrolled at the Center of Diagnosis and Treatment for Joint Diseases, Drum Tower Hospital affiliated to the Medical School of Nanjing University from 2010 to 2012. All the subjects received venography 3–5 days after operation. We measured P-selectin by means of a highly sensitive sandwich ELISA technique and a commercially available test reagent set. Results. No significant association was detected between P-selectin and DVT (all P??values > 0.05). ?sP-selectin was correlated with weight, APTT after operation, history of DVT, and diagnosis of primary disease ( P values were 0.03, 0.03, 0.04, and 0.02, resp.). Conclusion. P-selectin may not be a predicted factor for deep vein thrombosis after total hip arthroplasty. PMID:25057500

Shi, Dongquan; Xu, Xingquan; Xu, Zhihong; Nakamura, Takahiro; Pang, Yong; Yao, Chen; Wang, Feng; Chen, Dongyang; Dai, Jin; Jiang, Qing

2014-01-01

425

Beta-blocker prophylaxis for total knee arthroplasty patients: a case series.  

PubMed

Cardiac complications are an infrequent yet undesirable cause of morbidity and mortality following total knee arthroplasty. Perioperative prophylaxis with beta-blocker medication has been shown to reduce in-hospital cardiac deaths in noncardiac surgical patients. This study evaluated the safety and in-hospital cardiac complications of a consecutive cohort of 267 total knee arthroplasties in patients who followed a perioperative beta-blocker prophylaxis institutional protocol. The patients were categorized into three groups: A, already on a beta-blocker; B, beta-blocker prescribed by orthopaedic surgeon; and C, not given the medication. The 90-day mortality and in-hospital cardiac complications were evaluated. Of the patients who had 267 procedures, 203 (76%) received beta-blocker prophylaxis perioperatively: 110 (41.2%) were already on the medication preoperatively, 93 (34.8%) were prescribed the medication by the surgeon, and 64 (24%) did not receive this medication. There were no deaths within the first 90 days. There were two nonfatal myocardial infarctions (0.7%) and six other cardiac complications (2.2%). With a beta-blocker prophylaxis protocol implemented by one surgeon, 76% of total knee arthroplasty patients were given the medication and it was prescribed in 34.8% by the orthopaedic surgeon. In-hospital cardiac complications were low. PMID:21086929

Heim, Kathryn A; Lachiewicz, Mark P; Soileau, Elizabeth S; Lachiewicz, Paul F

2010-01-01

426

Have the media influenced the use of hip resurfacing arthroplasty? A review of UK print media  

PubMed Central

INTRODUCTION The aim of this study was to look at the different claims made about hip resurfacing arthroplasty in the popular UK print media and how this relates to findings in the scientific literature. METHODS A review of UK popular print media from January 1992 to June 2011 was performed using the Lexis® Library online news database. Only articles discussing the clinical results of hip resurfacing arthroplasty were included. After excluding duplicates, 49 newspaper articles were found suitable for this study. The main outcome measure was the claims made in popular UK print media about hip resurfacing. These were compared with the scientific publication. We reviewed the trend of use of hip resurfacing prostheses during the same period as reported in the National Joint Registry. RESULTS A disparity was found between the claims in the newspapers and published scientific literature. The initial newspaper articles highlighted only the positive aspects of hip resurfacing arthroplasty, without definitive contemporary evidence backing the claims. Most of these claims were refuted by future scientific publications. The initial positive media reports coincided with an increase in the use of hip resurfacing but the decline coincided with negative reports in the scientific literature. CONCLUSIONS The trend of the newspaper articles and that of the number of hip resurfacing prostheses implanted suggests that the media may have been partly responsible for the increased use of this prosthesis. The subsequent decrease was initiated by the scientific literature. PMID:22943335

Malviya, A; Stafford, GH; Villar, RJF; Villar, RN

2012-01-01

427

Intrapelvic Dislocation of a Femoral Trial Head During Primary Total Hip Arthroplasty Requiring Laparotomy for Retrieval  

PubMed Central

Background and Purpose: Total hip arthroplasty (THA) is a safe and reliable surgical procedure. However, THA also has intra- and postoperative complications. A dreaded and frustrating intraoperative complication during total hip arthroplasty is dislocation of the femoral trial head from the neck into the pelvis. Methods: Here, we report on the case of a 71-year old female patient with osteoarthritis of the left hip. Total hip arthroplasty was performed in a lateral position through a standard posterior approach. During intraoperative trial reduction, the femoral trial head dissociated from the taper and dislocated into the psoas compartment. Several unsuccessful attempts, including an additional ventral approach, were made to immediately retrieve the femoral trial head. Results and interpretation: Postoperative a Computerized Tomography (CT) was performed to locate the trial head, a secondary explorative laparotomy was undertaken to retrieve it. The retrieval of the femoral trial head should be performed in a planned second surgical procedure to avoid possible complications during the manipulation necessary for retrieval. PMID:23730381

Citak, Mustafa; Klatte, Till Orla; Zahar, Akos; Day, Kimberly; Kendoff, Daniel; Gehrke, Thorsten; Dörner, Arnulf; Gebauer, Matthias

2013-01-01

428

Venous Thromboembolism (VTE) Prophylaxis for Hip and Knee Arthroplasty: Changing Trends.  

PubMed

Venous thromboembolism (VTE) has been identified as an immediate threat to patients undergoing major orthopedic procedures such as total hip arthroplasty (THA) and total knee arthroplasty (TKA). Given the known dangers of VTE, arthroplasty surgeons are sensitive to the need for VTE thromboprophylaxis. However, the modalities of thromboprophylaxis used to minimize the risks to patients have been variable. Clinical practice guidelines have been published by several professional organizations, while some hospitals have established their own protocols. The 2 most popular guidelines are those published by the Academy of Orthopaedic Surgeons (AAOS) and American College of Chest Physicians (ACCP), both from North America. Prior to 2012, these recommendations varied depending on underlying definitions, methodology, and goals of the 2 groups. For the first time, both groups have similar recommendations that focus on minimizing symptomatic VTE and bleeding complications. The key to determining the appropriate chemoprophylaxis for patients is to balance efficacy of a prophylactic agent, while being safe in regards to bleeding complications. However, a multimodal approach that focuses on early postoperative mobilization and the use of mechanical prophylaxis, in addition to chemoprophylaxis, is essential. PMID:24706152

Budhiparama, Nicolaas C; Abdel, Matthew P; Ifran, Nadia N; Parratte, Sébastien

2014-06-01

429

Serum Metal Ion Concentrations in Paediatric Patients following Total Knee Arthroplasty Using Megaprostheses  

PubMed Central

The purpose of this study was to determine the concentrations of cobalt, chromium, and molybdenum in the serum of paediatric tumour patients after fixed hinge total knee arthroplasty. Further, these metal ion levels were compared with serum metal ion levels of patients with other orthopaedic devices such as hip and knee prostheses with metal-on-metal or metal-on-polyethylene articulation to find differences between anatomical locations, abrasion characteristics, and bearing surfaces. After an average follow-up of 108 months (range: 67 to 163) of 11 paediatric patients with fixed hinge total knee arthroplasty, the mean concentrations for Co and Cr were significantly increased while Mo was within the limits compared to the upper values from the reference laboratory. Furthermore, these serum concentrations were significantly higher compared to patients with a standard rotating hinge device (P = 0.002 and P < 0.001) and preoperative controls (P < 0.001). On the other hand, the serum levels of patients following MoM THA or rotating hinge arthroplasty using megaprostheses were higher. Therefore, periodic long-term follow-ups are recommended due to the rising concerns about systemic metal ion exposure in the literature. Upon the occurrence of adverse reactions to metal debris the revision of the fixed hinge implant should be considered. PMID:25276819

Friesenbichler, Jorg; Sadoghi, Patrick; Maurer-Ertl, Werner; Szkandera, Joanna; Glehr, Mathias; Ogris, Kathrin; Wolf, Matthias; Weger, Christian; Leithner, Andreas

2014-01-01

430

Preoperative Diagnostic for Periprosthetic Joint Infection Prior to Total Knee Revision Arthroplasty  

PubMed Central

Periprosthetic joint infection (PJI) after total knee arthroplasty remains a challenging problem. The aim of this study was to evaluate the accuracy of diagnostic knee aspiration and serum inflammatory markers in diagnostic of a PJI after total knee arthroplasty. Within 2011 and 2012, 46 patients received a one- or two-stage revision arthroplasty of the knee joint. These patients received a total number of 77 operations. A preoperative aspiration was performed in each case. We analyzed the microbiological and histological examinations of the samples from the aspiration and from the revision operation and additionally estimated serum inflammatory markers. The diagnostic aspiration had a specificity of 0.87, a sensitivity of 0.39, a positive predictive value of 0.67 and a negative predictive value of 0.68. For C-reactive protein the specificity was 0.61 and the sensitivity was 0.48, the serum white blood cell count had a specificity of 0.98 and a sensitivity of 0.23. Our data queries whether diagnostic joint aspiration or serum inflammatory markers are sufficient to verify or exclude a PJI.

Radtke, Kerstin; Ettinger, Max; Plaass, Christian; von Lewinski, Gabriela

2014-01-01

431

Multiple input electrode gap controller  

DOEpatents

A method and apparatus for controlling vacuum arc remelting (VAR) furnaces by estimation of electrode gap based on a plurality of secondary estimates derived from furnace outputs. The estimation is preferably performed by Kalman filter. Adaptive gain techniques may be employed, as well as detection of process anomalies such as glows.

Hysinger, Christopher L. (Austin, TX); Beaman, Joseph J. (Austin, TX); Melgaard, David K. (Albuquerque, NE); Williamson, Rodney L. (Albuquerque, NE)

1999-01-01

432

Large gap magnetic suspension system  

NASA Technical Reports Server (NTRS)

The design of a large gap magnetic suspension system is discussed. Some of the topics covered include: the system configuration, permanent magnet material, levitation magnet system, superconducting magnets, resistive magnets, superconducting levitation coils, resistive levitation coils, levitation magnet system, and the nitrogen cooled magnet system.

Abdelsalam, Moustafa K.; Eyssa, Y. M.

1991-01-01

433

The Racial Academic Achievement Gap  

ERIC Educational Resources Information Center

Closing the racial academic achievement gap is a problem that must be solved in order for future society to properly function. Minorities including African-American and Latino students' standardized test scores are much lower than white students. By the end of fourth grade, African American, Latino, and poor students of all races are two years…

Green, Toneka M.

2008-01-01

434

Multiple input electrode gap controller  

DOEpatents

A method and apparatus for controlling vacuum arc remelting (VAR) furnaces by estimation of electrode gap based on a plurality of secondary estimates derived from furnace outputs. The estimation is preferably performed by Kalman filter. Adaptive gain techniques may be employed, as well as detection of process anomalies such as glows. 17 figs.

Hysinger, C.L.; Beaman, J.J.; Melgaard, D.K.; Williamson, R.L.

1999-07-27

435

Mass gap from pressure inequalities  

E-print Network

We prove that a temperature independent mass distribution is identically zero below a mass threshold (mass gap) value, if the pressure satisfies certain inequalities. This supports the finding of a minimal mass in quark matter equation of state by numerical estimates and by substitution of analytic formulas. We present a few inequalities for the mass distribution based on the Markov inequality.

Tamas S. Biro; Andras Laszlo; Peter Van

2006-12-07

436

Routine use of antibiotic laden bone cement for primary total knee arthroplasty: impact on infecting microbial patterns and resistance profiles.  

PubMed

Antibiotic-laden bone cement (ALBC) is used in primary arthroplasties throughout Europe. In North America, ALBC is only FDA approved for revision arthroplasty after periprosthetic joint infection (PJI). No article has evaluated whether infecting microbial profile and resistance has changed with the introduction of ALBC. We hypothesized that prophylactic use of ALBC in primary total knee arthroplasty (TKA) has not had a significant impact on infecting pathogens, and antibiotic resistance profiles. A retrospective cohort analysis was conducted of all PJI patients undergoing primary TKA and total hip arthroplasty (THA) between January 2000 and January 2009. No significant change in the patterns of infecting PJI pathogens, and no notable increase in percentage resistance was found among organisms grown from patients with PJI that had received prophylactic antibiotic-loaded cement in their primary joint arthroplasty. Early findings suggest that routine prophylactic use of ALBC has not led to changes in infecting pathogen profile, nor has led to the emergence of antimicrobial resistance at our institution. PMID:24418770

Hansen, Erik N; Adeli, Bahar; Kenyon, Robert; Parvizi, Javad

2014-06-01

437

How to minimize infection and thereby maximize patient outcomes in total joint arthroplasty: a multicenter approach: AAOS exhibit selection.  

PubMed

Total joint arthroplasty is one of the most common and most successful orthopaedic procedures. Infection after total joint arthroplasty is a devastating problem that expends patient, surgeon, and hospital resources, and it substantially decreases the chances of a successful patient outcome. Postoperative infection affects approximately 1% to 7% of all total joint arthroplasties, at a cost of approximately $50,000 per infection. Decreasing postoperative periprosthetic joint infection is of the utmost importance for the total joint arthroplasty surgeon. Preoperative, perioperative, intraoperative, and postoperative measures to minimize infection and optimize patient outcomes in total joint arthroplasty are discussed. Preoperative measures include management of patients colonized by Staphylococcus aureus, nutritional optimization, and management of medical comorbidities. Perioperative measures include skin preparation and prophylactic antibiotics. Intraoperative measures include body exhaust suits, laminar flow, ultraviolet light, operating-room traffic control, surgical suite enclosures, anesthesia-related considerations, and antibiotic-loaded bone cement. Postoperative measures include continued antibiotic prophylaxis, blood transfusions, hematoma formation and wound drainage, duration of hospital stay, and antibiotic prophylaxis for future invasive procedures. PMID:23595076

Illingworth, Kenneth David; Mihalko, William M; Parvizi, Javad; Sculco, Thomas; McArthur, Benjamin; el Bitar, Youssef; Saleh, Khaled J

2013-04-17

438

Evaluation of biocompatible osteoconductive polymer shelf arthroplasty for the surgical correction of hip dysplasia in normal dogs.  

PubMed Central

Biocompatible osteoconductive polymer (BOP) shelf arthroplasty was performed on ten nondysplastic dogs, divided into five groups. Each group was evaluated at 6, 13, 17, 26 or 39 weeks postsurgery. Evaluation consisted of clinical, radiological and histological studies. The dogs were injected with three fluorochrome markers, 28 days, 14 days and 6 hours before euthanasia. Transverse sections of undecalcified arthroplasty site were examined by microradiography and fluorescence microscopy; surface-stained sections were evaluated by light microscopy. The BOP shelf arthroplasty was not technically difficult. Minimal mineralization of the shelf was noted by radiography, 26 and 39 weeks postop. A moderate to large amount of fibrous mature connective tissue was observed around the BOP fibers throughout the study. Bone ingrowth occurred around the BOP fibers, but was minimal within them. This osseous proliferation of the arthroplasty was very slow to take place; it was first noted microscopically 17 weeks postsurgery and was still minimal 39 weeks after surgery. These findings suggest that there may be interference to the osteoconductive properties of BOP by fibrous tissue. Ossification of the shelf arthroplasty was too unsatisfactory to recommend its use for the treatment of canine hip dysplasia. Images Fig. 2. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:7954118

Lussier, B; Lanthier, T; Martineau-Doizé, B

1994-01-01

439

Autologous transfusion of drain contents in elective primary knee arthroplasty: its value and relevance  

PubMed Central

Background Total knee arthroplasty is associated with significant post-operative blood loss often necessitating blood transfusions. Blood transfusions may be associated with transfusion reactions and may transmit human immunodeficiency virus, hepatitis C virus and hepatitis B virus, with devastating consequences. After total knee arthroplasty, transfusion of the contents of an autologous drain is becoming common practice. The aim of our study was to look at the effectiveness of these drains in elective primary total knee arthroplasty. Materials and methods A prospective study was conducted including 70 non-randomised patients. A normal suction drain was used in 35 patients (group A), whereas in the other 35 patients, a CellTrans™ drain was used (group B). All the operations were performed by four surgeons using a tourniquet with a medial parapatellar approach. Pre- and post-operative haemoglobin concentrations were recorded in both groups. A Student’s t-test was applied to determine the statistical significance of the data collected. Results The average fall in post-operative haemoglobin was 3.66 g/dL (SD 1.46; range, 0.6–7.0) among patients in whom the simple drain was used (group A) and 2.29 g/dL (SD 0.92; range, 0.6–5.9) among those in whom the CellTrans™ drain was used (group B) (p<0.0001). Twenty-five units of allogeneic blood were required in group A compared to four units in group B. The rate of transfusion was 5.7% (2 patients) in the group in which CellTrans™ drain was used and 25.7% (9 patients) in the group in which a simple suction drain was used. Discussion Total knee arthroplasty is associated with significant post-operative blood loss despite best operative technique. Autologous reinfusion of the contents of a CellTrans™ drain significantly reduces the rate of post-operative blood transfusion. This study indicates that the use of an autologous drain could be recommended as routine practice in primary total knee arthroplasty. PMID:21084012

Singh, Vinay Kumar; Singh, Pankaj Kumar; Javed, Sadaf; Kumar, Kuldeep; Tomar, Juhi

2011-01-01

440

Existing data sources for clinical epidemiology: The Danish Knee Arthroplasty Register  

PubMed Central

Purpose We described the settings, organization, content, and data quality of the Danish Knee Arthroplasty Register (DKR), as well as the incidence and the first results of the knee replacement procedures captured by the DKR. Our aim was to draw researchers’ attention to the DKR and its potential use in clinical epidemiological research. Patients and methods The DKR has collected data on all knee replacement procedures performed in Denmark since 1997. The validity of the register was compared with the Danish National Registry of Patients (DNRP). Incidence rate was calculated per 100,000 inhabitants. Implant survival was estimated by Kaplan–Meier method. Cox regression analyses were used to estimate the relative risk (RR) for revision with a 95% confidence interval (CI). Results A total of 62,586 primary knee arthroplasties and 6,683 revisions were registered in the DKR between January 1, 1997 and December 31, 2010. More than 90% of the private and public hospitals performing knee replacement surgery in Denmark have entered data to the DKR. Registration completeness of primary procedures and revisions has increased since the DKR initiation and was 88% in 2010 for both procedures, compared with registration in the DNRP. For primary knee arthroplasties, the annual incidence rate increased from 35.8 in 1997 to 155.2 in 2010 per 100,000 inhabitants. Incidence was higher in females than in males during the entire study period, and increased with age for both sexes. The overall implant survival after 14 years was 89% irrespective of diagnosis for surgery. Male patients had higher revision risk than females, and revision risk decreased with increasing age. Risk for any revision was higher for uncemented implants (RR = 1.48; 95% CI: 1.32–1.66), and lower for hybrid implants (RR = 0.84; 95% CI: 0.75–0.95) compared to cemented implants. Implant survival did not improve but remained the same throughout the study period when comparing patients operated in the periods 1997–2000 versus 2001–2003, 2004–2006, and 2007–2010. Conclusion The DKR is a valuable tool for quality monitoring and research in knee arthroplasty surgery due to the high quality and completeness of prospective, routinely collected data. Large population-based epidemiological studies can be performed in order to study trends as well as risk factors for poor clinical outcome following knee arthroplasty surgery. PMID:22701092

Pedersen, Alma B; Mehnert, Frank; Odgaard, Anders; Schr?der, Henrik M

2012-01-01

441

Gaps"  

ERIC Educational Resources Information Center

This study investigated the effect of daily quizzes on the performance of college students. Students in an introductory psychology course used their own wireless-enabled devices to take short Internet-based quizzes at the beginning of every class. The quiz items were drawn approximately equally from material covered in the readings and the…

What Works Clearinghouse, 2013

2013-01-01

442

Air Gap Effects in LX-17  

SciTech Connect

Three experiments done over twenty years on gaps in LX-17 are reported. For the detonation front moving parallel to the gaps, jets of gas products were seen coming from the gaps at velocities greater than the detonation velocity. A case can be made that the jet velocity increased with gap thickness but the data is scattered. For the detonation front moving transverse to the gap, time delays were seen. The delays roughly increase with gap width, going from 0-70 ns at 'zero gap' to around 300 ns at 0.5-1 mm gap. Larger gaps of up to 6 mm width almost certainly stopped the detonation, but this was not proved. Real-time resolution of the parallel jets and determination of the actual re-detonation or failure in the transverse case needs to be done in future experiments.

Souers, P C; Ault, S; Avara, R; Bahl, K L; Boat, R; Cunningham, B; Gidding, D; Janzen, J; Kuklo, D; Lee, R; Lauderbach, L; Weingart, W C; Wu, B; Winer, K

2005-09-26

443

Observational Properties of Protoplanetary Disk Gaps  

NASA Astrophysics Data System (ADS)

We study the effects of an annular gap induced by an embedded protoplanet on disk scattered light images and the infrared spectral energy distribution (SED). We find that the outer edge of a gap is brighter in the scattered light images than a similar location in a gap-free disk. The stellar radiation that would have been scattered by material within the gap is instead scattered by the disk wall at the outer edge of the gap, producing a bright ring surrounding the dark gap in the images. Given sufficient resolution, such gaps can be detected by the presence of this bright ring in scattered light images. A gap in a disk also changes the shape of the SED. Radiation that would have been absorbed by material in the gap is instead reprocessed by the outer gap wall. This leads to a decrease in the SED at wavelengths corresponding to the temperature at the radius of the missing gap material, and to a corresponding flux increase at longer wavelengths corresponding to the temperature of the outer wall. We note, however, that the presence of an annular gap does not change the bolometric IR flux; it simply redistributes the radiation previously produced by material within the gap to longer wavelengths. Although it will be difficult on the basis of the SED alone to distinguish between the presence of a gap and other physical effects, the level of changes can be sufficiently large to be measurable with current instruments (e.g., Spitzer).

Varnière, Peggy; Bjorkman, J. E.; Frank, Adam; Quillen, Alice C.; Carciofi, A. C.; Whitney, Barbara A.; Wood, Kenneth

2006-02-01

444

Electronic gap sensor and method  

DOEpatents

Disclosed are an apparatus and method for regulating the gap between a casting nozzle and a casting wheel in which the gap between the casting nozzle and the casting wheel is monitored by means of at least one sensing element protruding from the face of the casting nozzle. The sensing element is preferably connected to a voltage source and the casting wheel grounded. When the sensing element contacts the casting wheel, an electric circuit is completed. The completion of the circuit can be registered by an indicator, and the presence or absence of a completed circuit indicates the relative position of the casting nozzle to the casting wheel. The relative positions of the casting nozzle and casting wheel can thereby be selectively adjusted to continually maintain a predetermined distance between their adjacent surfaces. 5 figures.

Williams, R.S.; King, E.L.; Campbell, S.L.

1991-08-06

445

Hard-gapped Holographic Superconductors  

E-print Network

In this work we discuss the zero temperature limit of a "p-wave" holographic superconductor. The bulk description consists of a non-Abelian SU(2) gauge fields minimally coupled to gravity. We numerically construct the zero temperature solution which is the gravity dual of the superconducting ground state of the "p-wave" holographic superconductors. The solution is a smooth soliton with zero horizon size and shows an emergent conformal symmetry in the IR. We found the expected superconducting behavior. Using the near horizon analysis we show that the system has a "hard gap" for the relevant gauge field fluctuations. At zero temperature the real part of the conductivity is zero for an excitation frequency less than the gap frequency. This is in contrast with what has been observed in similar scalar- gravity-gauge systems (holographic superconductors). We also discuss the low but finite temperature behavior of our solution.

Pallab Basu; Jianyang He; Anindya Mukherjee; Hsien-Hang Shieh

2009-11-26

446

Homolumo Gap and Matrix Model  

E-print Network

We discuss a dynamical matrix model by which probability distribution is associated with Gaussian ensembles from random matrix theory. We interpret the matrix M as a Hamiltonian representing interaction of a bosonic system with a single fermion. We show that a system of second-quantized fermions influences the ground state of the whole system by producing a gap between the highest occupied eigenvalue and the lowest unoccupied eigenvalue.

I. Andric; L. Jonke; D. Jurman; H. B. Nielsen

2007-12-21

447

Gender Pay Gap in Poland  

Microsoft Academic Search

In this paper we examine the gender pay gap in Poland over 1987–1996, i.e., shortly before and during the transition to market\\u000a economy. The principle source of data used throughout the paper is the Household Budget Survey conducted by the Polish Central\\u000a Statistical Office. The study documents three major results. First, the transition to market economy in Poland favored women

Micha? Grajek

2003-01-01

448

Prometheus and the Keeler gap  

NASA Astrophysics Data System (ADS)

Linblad resonances with Saturn’s satellites are located at many radii in the rings. While some cause density or bending waves, others hold gap edges from spreading, like the 2:1 resonance with Mimas located at the B-ring edge, the 7:6 resonance with Janus at the A-ring edge, and the 32:31 resonance with Prometheus at the inner edge of the Keeler gap. The latter is the case of study here.Theoretically, the inner edge of the Keeler gap should have 32 regular sinusoidal lobes, where either the maximum or the minimum radius is expected to be aligned with Prometheus and rotating with its mean motion. We show that such is not the case. Fit of occultation data shows the presence of the 32:31 resonance, however, the fit residuals is as high as the amplitude of the resonance amplitude (about 2 km). Analysis of the ISS data, shows irregularities overlapping the lobes (Tiscareno et al. 2005, DPS), that follow Keplerian motion. These irregularities may be due to clumps of particles with different eccentricities than the rest of the edge particles. This phenomenon may be caused by the resonance, as it has not been observed at other circular edges were no resonance is present at their location. The ISS data also shows that the lobe’s minimum/maximum is not perfectly aligned with the longitude of Prometheus, which may be due to libration about the centre of the resonance.

Tajeddine, Radwan; Nicholson, Phillip D.; Hedman, Matthew M.; French, Richard G.; Tiscareno, Matthew S.; Burns, Joseph A.

2014-11-01

449

Gap junctions and chagas disease.  

PubMed

Gap junction channels provide intercellular communication between cells. In the heart, these channels coordinate impulse propagation along the conduction system and through the contractile musculature, thereby providing synchronous and optimal cardiac output. As in other arrhythmogenic cardiac diseases, chagasic cardiomyopathy is associated with decreased expression of the gap junction protein connexin43 (Cx43) and its gene. Our studies of cardiac myocytes infected with Trypanosoma cruzi have revealed that synchronous contraction is greatly impaired and gap junction immunoreactivity is lost in infected cells. Such changes are not seen for molecules forming tight junctions, another component of the intercalated disc in cardiac myocytes. Transcriptomic studies of hearts from mouse models of Chagas disease and from acutely infected cardiac myocytes in vitro indicate profound remodelling of gene expression patterns involving heart rhythm determinant genes, suggesting underlying mechanisms of the functional pathology. One curious feature of the altered expression of Cx43 and its gene expression is that it is limited in both extent and location, suggesting that the more global deterioration in cardiac function may result in part from spread of damage signals from more seriously compromised cells to healthier ones. PMID:21884887

Adesse, Daniel; Goldenberg, Regina Coeli; Fortes, Fabio S; Jasmin; Iacobas, Dumitru A; Iacobas, Sanda; Campos de Carvalho, Antonio Carlos; de Narareth Meirelles, Maria; Huang, Huan; Soares, Milena B; Tanowitz, Herbert B; Garzoni, Luciana Ribeiro; Spray, David C

2011-01-01

450

Ethnic and Racial Factors Influencing Well-being, Perceived Pain, and Physical Function After Primary Total Joint Arthroplasty  

Microsoft Academic Search

Background  Studies suggest, even when controlling for disease severity, socioeconomic status, education, and access to care, racial and\\u000a ethnic minorities receive lower-quality health care and have worse perceived pain and function before and after total joint\\u000a arthroplasty.\\u000a \\u000a \\u000a \\u000a \\u000a Question\\/purposes  We evaluated the influence of race and ethnicity on well-being, pain, and function after total joint arthroplasty and determined\\u000a whether race, ethnicity, sex, and

Carlos J. Lavernia; Jose C. Alcerro; Juan S. Contreras; Mark D. Rossi

2011-01-01

451

Thromboembolism prophylaxis with dabigatran leads to lower perioperative blood loss than with dalteparin in primary knee arthroplasty  

Microsoft Academic Search

Introduction  Low-molecular-weight heparins (LMWH) are commonly used in thrombosis prophylaxis after total knee arthroplasty. In contrast\\u000a to LMWH, dabigatran etexilate is an oral and direct acting anticoagulant. The hypothesis of the present study was that blood\\u000a loss occurring in total knee arthroplasty (TKA) is not greater after dabigatran etexilate than after dalteparin.\\u000a \\u000a \\u000a \\u000a \\u000a Method  All patients suffering from primary arthrosis of knee joint

Doerte Matziolis; Georg Matziolis; Carsten Perka

452

High-volume surgeons in regard to reductions in operating time, blood loss, and postoperative complications for total hip arthroplasty  

Microsoft Academic Search

Background  The purpose of this study was to clarify the volume-outcome relations for total hip arthroplasty, with a particular focus\\u000a on outcome variables such as operating time, blood loss, and postoperative complications.\\u000a \\u000a \\u000a \\u000a Methods  Using an Internet-based questionnaire survey, we identified 2965 total hip arthroplasties performed for osteoarthritis, idiopathic\\u000a osteonecrosis of the femoral head, rheumatoid arthritis, or hip fractures in 289 hospitals in

Hideo Yasunaga; Kazuaki Tsuchiya; Yutaka Matsuyama; Kazuhiko Ohe

2009-01-01

453

Low risk despite high endemicity of methicillin-resistant Staphylococcus aureus infections following elective total joint arthroplasty: a 12-year experience.  

PubMed

Abstract Background. It is unknown if low rates of arthroplasty infections due to methicillin-resistant Staphylococcus aureus (MRSA) can be achieved in a setting with endemic MRSA (30%). Methods. We performed a 12-year prospective cohort study (1996-2008) of patients undergoing elective knee and hip joint arthroplasties with long-term follow-up. Retrospective MRSA surveillance was undertaken using electronic databases. Results. A total of 6,100 total joint arthroplasties (4001 hip; 2099 knee; 441 (7%) revisions) were monitored for a total of 34,281 person-years of follow-up (median 64 months). MRSA carriage was detected in 126 (2.1%) episodes before arthroplasty and in 147 (2.4%) after arthroplasty. Seven (0.11%) deep arthroplasty infections due to MRSA were retrieved for an overall incidence of 2 episodes per 10,000 person-years. Six were primary surgical site infections, while one infection resulted from endocarditis. MRSA colonization pressure was 11,411 MRSA-positive days for a total of 138,044 patient-days (8.3%) among all orthopedic patients. Conclusion. Institution-wide MRSA endemicity does not necessarily lead to a high MRSA infection risk after elective hip and knee arthroplasty. PMID:21352084

Uçkay, Ilker; Lübbeke, Anne; Harbarth, Stephan; Emonet, Stéphane; Tovmirzaeva, Luisa; Agostinho, Americo; Longtin, Yves; Peter, Robin; Hoffmeyer, Pierre; Pittet, Didi