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Treatment of temporomandibular joint ankylosis: gap and interpositional arthroplasty with temporalis muscle flap  

Microsoft Academic Search

Purpose  The purpose of this study was to examine the effectiveness of gap and interpositional arthroplasty with temporalis muscle\\u000a flap in the treatment of the temporomandibular joint (TMJ) ankylosis.\\u000a \\u000a \\u000a \\u000a Materials and methods  This retrospective study was evaluated on 34 patients who were treated from February 2003 to July 2007. Diagnosis of TMJ ankylosis\\u000a was based upon the clinical examination and plain radiography

Mohammad Bayat; Amirali Badri; Nima Moharamnejad



Interposition arthroplasty options for carpometacarpal arthritis of the thumb.  


Carpometacarpal (CMC) arthritis of the thumb affects half of postmenopausal women and up to 25% of elderly men. This disease can cause significant disability in affected patients often necessitating surgical intervention. Various surgical options have been used to treat refractory CMC arthritis. Any successful surgical intervention must address three goals: removal of diseased joint surfaces, reconstruction of ligamentous stabilizers, and preservation of the joint space. In this article we will discuss various interposition arthroplasty options for CMC arthritis of the thumb. PMID:20670799

Bodin, Nathan D; Spangler, Ryan; Thoder, Joseph J



Bilateral osteoarthritis of the trapeziometacarpal joint treated by bilateral tendon interposition arthroplasty  

Microsoft Academic Search

Twenty-four flexor carpi radialis (FCR) tendon interposition arthroplasties of the trapezium for bilateral trapeziometacarpal osteoarthritis were reviewed. Pain was reduced in all cases. Function was improved in all right hands and in 92% of the left hands. FCR tendon interposition arthroplasty for bilateral trapeziometacarpal osteoarthritis yields satisfactory long-term results on both sides.

A. Damen; B. Van Der Lei; P. H. Robinson



The Artelon CMC spacer compared with tendon interposition arthroplasty  

PubMed Central

Background and purpose The Artelon CMC spacer is designed for surgical treatment of osteoarthritis (OA) in the carpometacarpal joint of the thumb (CMC-I). Good results using this degradable device were previously presented in a pilot study. We now present results from a larger randomized, controlled, multicenter study. Patients and methods 109 patients (94 females) with a mean age of 60 (42–83) years, suffering from painful CMC OA, were included in the study at 7 centers in Sweden. The patients were randomized to Artelon CMC spacer (test, n = 72) or tendon arthroplasty (control, n = 37) at a ratio of 2:1. Perceived pain was recorded on a visual analog scale (VAS) before treatment and after 3, 6, and 12 months, when measuring maximal tripod pinch strength (primary outcome measure). In addition, range of motion, radiographic findings, and functional testing were recorded pre- and postoperatively. Results Swelling and pain were more common in the test group and 6 implants were removed because of such symptoms. 5 of these patients did not receive antibiotics preoperatively according to the study protocol. In a per-protocol analysis, i.e. patients without signs of concomitant OA in the scaphoid-trapezium-trapezoid (STT) joint and those in the test group who received antibiotics, the mean difference in tripod pinch strength increase, adjusted for baseline, was 1.4 kg in favor of the test group (not statistically significant). Statistically significant pain relief was achieved in both groups, with perceived pain gradually decreasing during the follow-up period. In the intention-to-treat analysis but not in the per-protocol analysis, significantly better pain relief (VAS) was obtained in the control group. Patient-perceived disability evaluated by the DASH questionnaire improved in both groups. Interpretation The Artelon CMC spacer did not show superior results compared to tendon interposition arthroplasty. Proper use of preoperative antibiotics and a thorough patient selection appear to be important for the results.

Wiig, Monica; Alnehill, Hakan; Berggren, Magnus; Bjornum, Sten; Geijer, Mats; Kopylov, Philippe; Sollerman, Christer



Thumb carpometacarpal osteoarthritis: trapeziectomy versus pyrocarbon interposition implant (Pi2) arthroplasty.  


We retrospectively compared the short-term outcomes of 18 thumbs that had a trapeziectomy and 18 that had a pyrocarbon interposition implant (Pi2) arthroplasty in 33 patients. We measured the Disability of the Arm, Shoulder, and Hand (DASH) and Short Form 36 (SF-36) scores at a mean of 20 months. Pain severity was assessed using a visual analogue scale (VAS), and level of patient satisfaction was assessed using a 5-point scale. The mean DASH scores at follow up were 27 for those that had a trapeziectomy and 35 for those that had a Pi2 arthroplasty (p = 0.001). There was no difference in the VAS for pain, SF-36 scores, or other parameters assessed. Six out of 18 (33%) thumbs in the Pi2 group had multiple operations, usually for dislocation or subluxation of the implant. The early results of Pi2 arthroplasty show a high complication rate compared with trapeziectomy and no identifiable benefit. PMID:22223584

Maru, M; Jettoo, P; Tourret, L; Jones, M; Irwin, L



Treatment of thumb carpometacarpal arthritis with arthroscopic hemitrapeziectomy and interposition arthroplasty.  


The carpometacarpal joint of the thumb is a common site of degenerative arthritis. Several surgical treatments exist, but arthroscopic management offers the potential benefit of earlier recovery. The current study evaluated the early clinical outcomes of a procedure involving arthroscopic hemitrapeziectomy with Artelon spacer (Artimplant, Västra Frölunda, Sweden) interposition arthroplasty into the newly created carpometacarpal space.A chart review of 9 patients treated with thumb carpometacarpal arthroscopic hemitrapeziectomy and Artelon spacer interposition arthroplasty between September 2005 and January 2009 was performed for postoperative complications, range of motion, and pinch strength (percentage of the contralateral limb). Subjective outcomes were analyzed by the Quick Disabilities of the Arm, Shoulder, and Hand questionnaire and the Patient-rated Wrist Evaluation. Mean follow-up was 23.4 months (range, 13-33 months). All patients maintained full range of motion. By the 1-year follow-up, mean pinch strength returned to 59%± 19.1% of the contralateral limb strength. The Quick Disabilities of the Arm, Shoulder, and Hand and the Patient-rated Wrist Evaluation scores were 12.3 ± 7.6 and 26.8 ± 23.5, respectively. No significant complications occurred, and 1 patient with symptoms of synovitis was successfully treated with a corticosteroid injection. This study revealed excellent short-term results at the minimum 1-year follow-up for a less invasive treatment option that is appropriate for select patients with moderate thumb carpometacarpal arthritis (Eaton stages 2 and 3). The authors demonstrated a comparably good outcome of arthroscopic hemitrapeziectomy with Artelon spacer interposition arthroplasty with no evidence of foreign-body reaction. The authors also demonstrated the potential role of corticosteroid injections in the setting of a postoperative inflammatory reaction. PMID:23218633

Park, Min Jung; Lee, Arthur T; Yao, Jeffrey



Gelfoam first metatarsophalangeal replacement/interposition arthroplasty--a case series with functional outcomes.  


Reported below are the functional results of a case-series of Gelfoam®-based first metatarsophalangeal total joint replacements using an interposition arthroplasty technique carried out between April 1997 and December 2007. All patients who underwent Gelfoam-based arthroplasty under the care of a single surgeon were included; outcome scores and complications were recorded. A total of 31 joints in 31 consecutive patients were followed for a mean duration of 64 (range 24-150) months, and the mean patient age at the time of operation was 48±9 (range 35-80) years. Hallux rigidus was the primary diagnosis in all of the cases except one in which a failed chevron ostetomy was the indication for treatment. The mean American Orthopaedic Foot & Ankle Society Hallux-Metatarsophalangeal-Interphalangeal score increased from an average of 35 pre-operatively to an average of 74 at final follow-up (range 67-100), with 20 (64.5%) joints rated good to excellent. One (3.5%) joint was fused 6 months after the arthroplasty procedure. Based on these results, we concluded that first MTPJ total joint Gelfoam™-based interpostion arthroplasty is a cheap alternative to other joint replacement systems for the MTP joint. The results appear similar to those achieved using more expensive devices. PMID:21277765

Heller, Eyal; Robinson, Dror



Pyrocarbon interposition wrist arthroplasty in the treatment of failed wrist procedures.  


Treatment of failures after prior wrist surgeries with major articular destruction is challenging. In most cases, total wrist fusion is the only possible salvage procedure. We propose a new interposition arthroplasty with a pyrocarbon implant called Amandys. A total of 16 patients, 14 men and 2 women, with a mean age of 56 years were operated on for a failure of wrist surgery performed previously, with an average time lapse of 12 years. The prior surgeries were partial wrist arthrodesis in seven cases, silicone implant interpositions in five cases, advanced Kienböck disease (Lichtman IV) treatment in two cases, proximal row carpectomy in one case, and an isolated scaphoidectomy in one case. A prospective study with clinical and radiological evaluation was performed with a mean follow-up of 24 months (6 to 41 months). Pain and function showed significant improvement. The mean pain score decreased from 7 of 10 to 4 of 10, postoperatively. The mean grip strength was 19?kg (53% of the contralateral side), and the mean range of motion in flexion extension was 68 degrees. Mean strength and range of motion did not change significantly with the operation. The mean QuickDASH (Disability Arm Shoulder and Hand) score decreased from 59 of 100 to 39 of 100. The mean Patient-Rated Wrist Evaluation decreased from 57 of 100 to 33. Two patients (12.5%) required revision for implant repositioning. No dislocation or subsidence of the implant was noted. Pyrocarbon interposition arthroplasty is a new option for treatment of advanced wrist destruction. Preliminary short-term results suggest that it may be a reliable alternative to total wrist fusion. The level of evidence of this study is IV (therapeutic case series). PMID:23904977

Bellemère, Philippe; Maes-Clavier, Catherine; Loubersac, Thierry; Gaisne, Etienne; Kerjean, Yves; Collon, Sylvie



Early functional improvement after a modified ligament reconstruction tendon interposition arthroplasty for thumb basal joint arthritis.  


Many modifications to trapeziectomy have been proposed for the treatment of thumb basal joint arthritis. Their final outcomes have been discussed intensively, whereas functional changes in the early post-operative period have not been fully documented. The purpose of the present study is to evaluate an early functional change following our modified ligament reconstruction with tendon interposition (LRTI) arthroplasty. Nine patients (ten thumbs) were included in this study. Pain levels, strength, and mobility were assessed before and after surgery at intervals of two months. Pain level significantly improved at two months after surgery. Grip and pinch strengths had increased gradually after a temporal decrease at two-month follow-up, and were significantly stronger at six months after surgery. Palmar abduction improved significantly at six months after surgery, whereas opposition did not change significantly. A modified LRTI is an effective procedure in terms of early functional improvement of pain, strength, and mobility. PMID:19378359

Miura, Toshiki; Osuka, Koji; Itoh, Shozo; Nakagawa, Takumi; Kawano, Hirotaka; Nakamura, Kozo



Elbow interposition arthroplasty in children and adolescents: long-term follow-up  

PubMed Central

A long-term follow-up was made of 12 elbows operated upon between 1971 and 1986, with more than 20 years’ follow-up, in nine males and three females, age at the time of surgery between 10 and 19 years . Eight right and four left elbows were involved, and there were three aetiological causes. Seven cases were sequelae of elbow fractures, of which five were supracondylar and two were of the olecranon. There were four cases of juvenile rheumatoid arthritis and one was post-osteomyelitis. The surgical technique involved a modification made by Vainio of MacAusland’s technique (wider resection of the osseous ends and total covering of the bloody surfaces) [5, 9]. After extirpating the tissue blocking the joint, we proceeded to remodel the distal humerus in a wide V shape, the proximal end of the ulnar and, if necessary, the radial head. The proximal end of the ulna was sectioned transversely. All surgery was carried out sub-periosteally. Then, an interposition material was placed in one piece and sutured over the distal humerus and cut ends of the ulna and radius. The articular ends were brought together, and the capsule was closed using equidistant stitching, as is the skin. A small compression bandage was applied, and the arm was immobilised with a collar and cuff sling, with the forearm flexed to slightly less than a right angle. In ten cases, the interposition material was fascia lata grafts; in one case, skin graft and in one case, Gelfoam graft. Early rehabilitation began when post-operative pain allowed. Follow-up ranged from 25 to 32 years. Pre-surgical movement ranged between 90° and 120° of flexion and 30° and 90° of extension. Post-operative range varied between 90° and 150° of flexion. The five cases of full pre-operative ankylosis achieved between 90° and 150° of flexion and between 0° and 70° of extension. The total range of motion at the latest follow-up varied from 35° to 150°. Patients who were able to perform flexion of 120° or more were considered to be excellent, those between 90° and 119° were graded good, from 60° to 89° fair and those 59° or less poor. The ability to attain a hand to mouth position requires a mobility of 120°. We obtained excellent results in two patients, good results in three, fair results in four and poor results in three. The fascia lata was used in 83% of cases, obtaining excellent to good results in five patients (41%). Elbow interposition arthroplasty has its indications in children and adolescents where arthrodesis or total joint replacement cannot be performed.

Rodriguez, Janeth; Oliver, Guillermo



A modified technique of interpositional arthroplasty in treating the Basal joint arthritis of the thumb in a Chinese population.  


We performed a retrospective review of 22 thumbs in 22 Chinese patients attending for the basal joint arthritis of the thumb over the last 14 years. There were 16 women and six men with a mean age of 50 years old. All were treated surgically by partial trapeziectomy and volar oblique ligament reconstruction with flexor carpi radialis tendon and interpositional arthroplasty with a free palmaris longus tendon ball after failure of conservative treatment. The mean follow-up time was 48 months. Radiographs did not show any differences in the arthroplasty space index, arthroplasty space, trapezial space ratio and scaphoid-thumb metacarpal distance at the pre-operative evaluation and at the final follow-up evaluation. There was significant difference in the pain score, grip strength, Kapandji score and functional status before and after surgery at final follow-up period. One patient had complex regional pain syndrome which was resolved after receiving a course of anti-inflammatory drugs and physiotherapy. The authors suggest that the modified technique of partial trapeziectomy with tendon interpositional arthroplasty is a safe and effective method in treating basal joint arthritis of the thumb with good short term functional and radiological outcomes and minimal complication. PMID:20135733

Wong, Tak-Chuen; Ip, Fu-Keung



Full-thickness skin graft interposition after temporomandibular joint ankylosis surgery. A study of 31 cases.  


Recurrence is a major problem after release of temporomandibular joint ankylosis. Early physiotherapy and choice of interpositional material are important in preventing recurrence. Currently, the most used technique is gap arthroplasty associated with coronoidectomy, temporalis muscle flap interposition and reconstruction of the condylar unit with a costochondral graft. Full-thickness skin graft interposition, using the technique described by Popescu & Vasiliu, can also be used. This retrospective review of 31 patients confirms the reliability of full-thickness skin graft interposition. Results were successful in 90% of the 20 patients with follow-up longer than one year. PMID:10535529

Chossegros, C; Guyot, L; Cheynet, F; Blanc, J L; Cannoni, P



Congenital cheek teratoma with temporo-mandibular joint ankylosis managed with ultra-thin silicone sheet interpositional arthroplasty  

PubMed Central

Primary cheek teratomas are rare with < 5 reported cases. None had associated temporo mandibular joint ankylosis (TMJA). The fundamental aim in the treatment of TMJA is the successful surgical resection of ankylotic bone, prevention of recurrence, and aesthetic improvement by ensuring functional occlusion. Early treatment is necessary to promote proper growth and function of mandible and to facilitate the positive psychological development of child. Inter-positional arthroplasty with ultra-thin silicone sheet was performed. Advantages include short operative time, less foreign material in the joint space leading to negligible foreign body reactions and least chances of implant extrusion. Instead of excising a large bony segment, a thin silicone sheet was interposed and then sutured ensuring preservation of mandibular height. Aggressive post-operative physiotherapy with custom made dynamic jaw exerciser was used to prevent recurrence.

Bhatnagar, Ankur; Verma, Vinay Kumar; Purohit, Vishal



Is aggressive gap arthroplasty essential in the management of temporomandibular joint ankylosis?-a prospective clinical study of 15 cases.  


The purpose of this three-year, prospective, follow-up study was to evaluate whether aggressive gap arthroplasty is essential in the management of ankylosis of the temporomandibular joint (TMJ). Fifteen patients were treated by the creation of a minimal gap of 5-8mm and insertion of an interpositional gap arthroplasty using the temporalis fascia. Eleven patients had unilateral coronoidectomy and 4 bilateral coronoidectomy based on Kaban's protocol. Preoperative assessment included recording of history, clinical and radiological examinations, personal variables, the aetiology of the ankylosis, the side affected, and any other relevant findings. Patients were assessed postoperatively by a surgeon unaware of the treatment given for a minimum of 3 years, which included measurement of the maximal incisal opening, presence of facial nerve paralysis, recurrence, and any other relevant findings. Of the 15 patients (17 joints), 12 had unilateral and three had bilateral involvement, with trauma being the most common cause. The patients were aged between 7 and 29 years (mean (SD) age 20 (8) years). Preoperative maximal incisal opening was 0-2mm in 8 cases and 2-9mm in 9. Postoperatively adequate mouth opening of 30-40mm was achieved in all cases, with no recurrence or relevant malocclusion during 3-year follow up. However, patients will be followed up for 10 years. Aggressive gap arthroplasty is not essential in the management of ankylosis of the TMJ. Minimal gap interpositional arthroplasty with complete removal of the mediolateral ankylotic mass is a feasible and effective method of preventing recurrence. PMID:23219020

Babu, Lokesh; Jain, Manoj Kumar; Ramesh, C; Vinayaka, N



Arthroscopic indications and technique for artelon interposition arthroplasty of the thumb trapeziometacarpal joint.  


Advanced basal joint arthritis that has failed conservative treatment has traditionally been treated with some type of procedure that encompasses complete trapezial excision. An arthroscopic technique entailing only minimal trapezial debridement coupled with insertion of a synthetic interposition material is described. This provides the implicit benefits of a minimally invasive procedure, with less pain and faster recovery, along with the great advantage of trapezium preservation. The surgical technique is described along with a preliminary clinical series supporting its use. PMID:19060684

Badia, Alejandro



Use of a Kirschner wire for distraction and capsular flaps in the Keller interpositional arthroplasty.  


We describe a simplified capsular interpositional technique for the Keller bunionectomy that uses a Kirschner wire to interpose the capsule into the first metatarsophalangeal joint without requiring sutures. The capsule acts as a biologic spacer in the first metatarsophalangeal joint, allowing for fibrosis to fill the void created, with the Kirschner wire maintaining the distance between the metatarsal head and the stump of the proximal phalanx. This creation of a nonpainful pseudarthrosis prevents shortening of the hallux and retraction of the base of the proximal phalanx on the metatarsal head. PMID:18685056

Becerro de Bengoa Vallejo, Ricardo; Losa Iglesias, Marta Elena; Viejo Tirado, Fermin; Prados Frutos, Juan Carlos; Jules, Kevin T


Lateral thigh fascia lata as interpositional graft for temporomandibular joint ankylosis.  


Successful management of temporomandibular joint (TMJ) ankylosis depends on adequate gap arthroplasty and interpositional graft; the objective is to produce a functioning pseudoarthrosis that prevents reankylosis and provides adequate mobility. Several interpositional grafts have been used for the treatment of temporomandibular joint ankylosis such as indigenous pterygomasseteric sling, temporalis muscle/fascia, auricular cartilage, fat and dermis-fat. Lateral thigh fascia lata (LTFL) graft is commonly used in neurosurgical practice and in other surgical specialities. We present a case of lateral thigh fascia lata used as interpositional graft for the treatment of a unilateral fibrous temporomandibular joint ankylosis. PMID:23997493

Alemán, Ramón Manuel; Martínez, María Guadalupe



Long term results of surgical intervention for osteoarthritis of the trapeziometacarpal joint : comparison of resection arthroplasty, trapeziectomy with tendon interposition and trapezio-metacarpal arthrodesis.  


Trapeziometacarpal osteoarthritis is a common entity, often bilateral and predominantly affecting postmenopausal women. In the case of failure of conservative treatment, surgery is a good option. The aim of this study was to compare three surgical procedures. 63 patients (74 thumbs) with osteoarthritis of the trapezio-metacarpal joint were surgically treated; 54 patients were seen for follow-up, 7 had died and 2 were lost to follow-up. The patients were stratified according to treatment; resection arthroplasty (the joint surface's of the metacarpal and the trapezium are resected) (18 thumbs), trapeziectomy with tendon interposition (17 thumbs) or trapezio-metacarpal arthrodesis (28 thumbs). Baseline characteristics were comparable in the three groups for mean age at operation, Eaton classification, left right distribution and dominant hands operated. The average follow-up was 13 years for the resection group, 8 years for the trapeziectomy group and 9 years for the arthrodesis group. No statistically significant difference between the three groups was found for the visual analogue pain and satisfaction scale, pain frequency nor DASH score. Patients in the trapeziectomy group had significantly less pain compared to the arthrodesis group (p=0.025). Statistically, radial abduction was significantly better after trapeziectomy compared to resection arthroplasty (p<0.01) or arthrodesis (p=0.01). There was no difference among the three groups in grip and tip pinch strength nor in pain on palpation. None of the patients in the trapeziectomy group needed a re-operation, one patient in the resection arthroplasty group had a re-operation, and 22 patients in the arthrodesis group had one or more re-operations for hardware removal or because of a complication. This study shows that the resection arthroplasty has equally good long term results compared to trapeziectomy combined with tendon interposition or arthrodesis. Resection arthroplasty is performed through a single incision and is technically simple. In our clinic resection arthroplasty is therefore the preferred technique for the treatment of osteoarthritis of the trapeziometacarpal joint. PMID:17021835

Raven, E E J; Kerkhoffs, G M M J; Rutten, S; Marsman, A J W; Marti, R K; Albers, G H R



The use of Swanson silastic interposition arthroplasty in revision thumb-base surgery for failed trapeziectomy; a case series of 10 patients.  


Patients who report ongoing adverse symptoms following trapeziectomy may require revision surgery. We present a series of 10 patients who underwent revision surgery using a Silastic interpositional finger joint arthroplasty. Mean age was 60 (range 48-70) years, with a mean interval between primary and revision surgery of 34 (range 12-84) months. Review was performed at an average of 53 (range 21-136) months. Nine of the 10 patients reported improvement in pain, and all patients reported improvement in pinch grip, activities of daily living, and satisfaction at having undergone revision surgery. There were no complications. We found good medium-term results and high satisfaction rates. We advocate this technique as an effective treatment option in these difficult cases, provided other treatable causes of poor outcome are excluded. PMID:22618556

Umarji, S I M; Arnander, M W T; Evans, D M



The mean seven years' results of the use of poly-l/d-lactic Acid (pldla) interposition implant and bone packing in revision metacarpophalangeal arthroplasty: a prospective cohort study.  


Background and Aims: Revision arthroplasty of metacarpophalangeal (MCP) joints in chronic inflammatory arthritis patients after silicone implants is challenging due of severe bone loss and soft tissue deficiencies. The aim of this study was to evaluate the outcome of revision MCP arthroplasty using poly-L/D-lactic acid 96:4 (PLDLA) interposition implant and morcelised allograft or autograft bone packing in patients with failed MCP arthroplasties and severe osteolysis. Material and Methods: The study group consisted of 15 patients (15 hands and 36 joints) at a mean follow-up of seven years (range 5-10 years). The radiographs were reviewed for osteolysis and incorporation of the grafted bone. The clinical assessments included active range of motion, evaluation of pain, subjective outcome and assessment of grip power. Results: PLDLA interposition arthroplasty combined with bone packing provided satisfactory pain relief, but function was limited. Radiographic analysis showed complete incorporation of the grafted bone to the diaphyseal portion of the host metacarpal and phalangeal bones in 30 of the 36 joints. All the patients had very limited grip strength, both on the operated and non-operated side. Conclusions: Due to soft tissue deficiencies long-term function and alignment problems can not be resolved with PLDLA interposition implant. PMID:23238502

Tiihonen, R; Honkanen, P B; Belt, E A; Ikävalko, M; Skyttä, E T



The reliability of navigation-guided gap technique in total knee arthroplasty.  


The OrthoPilot TKA navigation system (B. Braun Aesculap, Tuttlingen, Germany) offers software to optimize soft tissue balance using gap balance techniques. However, there are no studies on the reliability of the navigation-guided gap technique. The goal of this study is to establish the reliability of the navigation-guided gap technique. The investigators measured flexion and extension gap in the medial and lateral sides of the knee joint after bone resection to evaluate the reliability of navigation-guided soft tissue balancing. Gap data from 100 cases of navigation-guided total knee arthroplasty were analyzed. We defined trapezoidal gap (unsatisfactory soft tissue balance) as a gap difference < 3 mm between the medial and lateral sides in extension and a 5 mm difference in 90 degrees of flexion. Furthermore, gap difference between flexion and extension greater than 3 mm on the medial side and 5 mm on the lateral side was also considered a trapezoidal gap. Among 100 cases, 84 showed rectangular (acceptable) gap, and 16 showed trapezoidal gap. We also evaluated the correlation between clinical results including range of motion and soft tissue balance as well as characteristics of trapezoidal gap. This study suggests that the navigationguided gap technique is a reliable method for optimizing soft tissue balance. PMID:19298036

Han, Seung-Beom; Nha, Kyung-Wook; Yoon, Jung-Ro; Lee, Dae-Hee; Chae, In-Jung



Long-term outcome of trapeziectomy with ligament reconstruction and tendon interposition (LRTI) versus prosthesis arthroplasty for basal joint osteoarthritis of the thumb.  


Several surgical techniques are available to treat thumb basal joint arthritis. In this study, we compare the long-term results of a thumb basal joint prosthesis (de la Caffinière or Roseland type prosthesis) with those of trapeziectomy with ligament reconstruction and tendon interposition (LRTI). We could not find any difference between both techniques with respect to impairment, pain reduction, patient satisfaction and disability. PMID:23821964

De Smet, Luc; Vandenberghe, Lore; Degreef, Ilse



Shape of the joint gap for 90° and 120° knee flexion after total knee arthroplasty  

Microsoft Academic Search

Background  The joint gap is set rectangular at 90° flexion during total knee arthroplasty (TKA). However, the condition of the joint\\u000a gap in deep knee flexion is obscure.\\u000a \\u000a \\u000a \\u000a Methods  The method for obtaining a posteroanterior view radiograph of the knee at 90° flexion (the epicondylar view) was modified,\\u000a and a method to obtain an anteroposterior view radiograph at 120° flexion (deep flexion

Ryuji Nagamine; Keiichi Kondo; Hiroshi Nomura; Koichi Kanekasu; Motoki Sonohata; Yoichi Sugioka



Esophageal replacement with colon interposition in children.  

PubMed Central

During a 21-year period, 39 colon interposition operations were performed on 37 children at the UCLA Medical Center and the Childrens Hospital of Los Angeles. The average age at the time of operation was 5.8 years. The indications for operation were esophageal atresia in 23 patients and other benign strictures in 14 patients. The duration of patient follow-up ranged from 6 months to 21 years (mean: 9.7 years). The most common complications were esophagocolonic anastomotic leak (12), esophagocolonic anastomotic stricture (14), pneumonia, and pneumothorax. Fourteen of the 25 patients with retrosternal colon interposition had complications (56%), whereas 10 of 14 patients with left thoracic colon interposition had complications (71%). One patient died (mortality: 3%) after left thoracic interposition because of severe respiratory distress associated with other malformations. Each of the 18 patients with isoperistaltic colon interposition showed rapid transit and emptying, provided that obstruction or extensive dilatation did not occur; reverse colon segments were more dilated and emptied more slowly. The 25 patients with retrosternal colon segments had less colonic distension with better emptying than did the 14 patients with left thoracic interposition. Thirty-two of the 36 children increased their weight percentile after colon interposition. Within 2 years after cervical anastomotic stricture or leak, 78% of these children were asymptomatic and gaining weight. Thirty-one of the 37 patients (84%) had excellent results with colon interposition, with a mean follow-up of 9.7 years. Most of the major postoperative complications occurred within the first few weeks and were corrected during the first few months after operation. Preservation of the esophagus should be the surgeon's first priority; however, prolonged attempts to elongate the esophagus for anastomosis in certain patients with long-gap esophageal atresia have been more hazardous in our experience than has colon interposition. Images FIG. 1.

Stone, M M; Fonkalsrud, E W; Mahour, G H; Weitzman, J J; Takiff, H



Cystocele repair with interpositional grafting.  


This article discusses a systematic approach to the repair of cystoceles using interposition grafting. Surgeons' opinions vary regarding which graft is most appropriate as there are several varieties for mesh interposition. High-grade cystocele repair using the porcine dermis interposition graft is successful and associated with few complications. Cystocele repair is typically low grade and does not require additional surgery. PMID:21353079

Leu, Patrick B; Scarpero, Harriette M; Dmochowski, Roger R



Excisional arthroplasty for scaphotrapeziotrapezoidal osteoarthritis.  


Symptomatic scaphotrapeziotrapezoidal (STT) joint osteoarthritis may occasionally require surgery. In the absence of dorsal midcarpal instability, acceptable results may be obtained by an excisional STT joint arthroplasty. After distal scaphoid resection, however, forces are no longer transmitted along the radial column of the wrist. This often results in slight malrotation of the proximal row into extension. To mitigate this problem, different strategies have been proposed (dorsal midcarpal capsulodesis, palmar radioscaphoid capsulodesis, tendon interposition, or pyrocarbon implant interposition). As compared to STT fusion, excisional arthroplasty is less technically demanding, requires less prolonged immobilization, and has fewer complications. PMID:21371628

Garcia-Elias, Marc



Adenocarcinoma in Colonic Interposition  

PubMed Central

A 59-year-old female with dysphagia presented to our clinic. In childhood, she underwent colonic interposition due to anastomotic stricture after a previous proximal gastrectomy for gastric ulcer perforation. Imaging studies revealed a space-occupying lesion obstructing the distal interposed colon. At surgery, completion gastrectomy with segmental colectomy was carried out, and Roux-en-Y coloenterostomy and enteroenterostomy were performed.

Grunner, Shahar; Gilshtein, Hayim; Kakiashvili, Eliahu; Kluger, Yoram



Interpositional biarticular disk implant  

US Patent & Trademark Office Database

An interpositional biarticular disk implant (11) having a circular peripheral rim, a generally toroidal axial center opening (13) and convex upper and lower surfaces (15, 17) is implanted between resected concave surfaces of the metacarpal base and the trapezium or other carpal bone in a CMC joint replacement. The disk (11) is anchored in operative position through the use of a flexible cord, such as a harvested tendon that passes through the center opening (13) and through osseous passageways created in the two facing bones.



Imageless navigation assisted total knee arthroplasty with comprehensive gap balancing in medial osteoarthritic varus knees with anatomic variations.  


This study retrospectively compares the postoperative alignment of imageless navigation assisted (INA) total knee arthroplasties (TKAs) using comprehensive gap balancing with that of conventional TKAs in 72 medial osteoarthritic varus knees with coronal plane anatomic variations of the distal femur and proximal tibia. The navigation group showed significantly lower postoperative differences in the mechanical axis (MA) of the lower limb (p = 0.003), with fewer outliers (p = 0.03), better femoral component positioning relative to the MA (p = 0.02), and less difference between the weight-bearing MA of the lower limb and the MA of the femur (p = 0.003) and tibia (p = 0.005). INA comprehensive gap balancing TKA provides a better correction of leg alignment and better orientation of components with respect to the MA in medial osteoarthritic varus knees with lateral bowing of the femoral shaft and external rotation of the femur and/or proximal tibia vara, thus indicating the superiority of this approach over the conventional technique in such situations. PMID:20807170

Tyagi, Vineet; Kim, Tae-Hoon; Hwang, Jin Ho; Oh, Kwang Jun



Long term outcome of trapeziectomy with ligament reconstruction/tendon interposition versus thumb basal joint prosthesis.  


Several surgical techniques to treat thumb basal joint arthritis have been described. In this study we compared the results of a cemented thumb basal joint with trapeziectomy with a ligament reconstruction and tendon interposition. A questionnaire was sent to all 519 patients, 322 (with 382 procedures) responded. No significant differences were found when comparing impairment, pain, patient satisfaction and disability. Given the fact that the superiority of a prosthesis cannot be proven and the cost of the implant is greater, we recommend the trapeziectomy with ligament reconstruction and tendon interposition as opposed to arthroplasty as the first choice in the treatment of basal joint osteoarthritis of the thumb. PMID:23221185

Vandenberghe, L; Degreef, I; Didden, K; Fiews, S; De Smet, L



Reconstruction of the trapeziometacarpal joint in inflammatory joint disease using interposition of autologous tendon or poly-L-D-lactic acid implants: a prospective clinical trial.  


Interposition arthroplasty with bioreplaceable poly-L-D-lactic acid (PLDLA) implants has yielded promising results in reconstruction of rheumatoid hands. In this prospective clinical study we compared the PLDLA implant arthroplasty (n = 17) with that of tendon interposition (n = 12) for destruction of the trapeziometacarpal joint in arthritic patients. There was no significant difference between the two groups preoperatively. At one-year follow-up, the mean pain and function scores were 5 and 13 in the PLDLA group, and 19 and 43 in the tendon interposition group, respectively. At one-year follow-up the visual analogue scale (VAS) for function of the PLDLA group differed significantly from that of the tendon interposition group (p = 0.03). This difference was not found at three months postoperatively, and disappeared again at two-year follow-up. Otherwise, no significant difference was found between the groups in the pain or function scores, functional tests, or range of movement. Bioreplaceable interposition arthroplasty works at least as well as tendon interposition. The operation is easier. PMID:22471260

Tiihonen, Raine P; Skyttä, Eerik T; Kaarela, Kalevi; Ikävalko, Mikko; Belt, Eero A



[Interpositional arthrodesis of the first metatarsophalangeal joint].  


Background: Interpositional arthrodesis of the first metatarsophalangeal joint is a rare procedure which is indicated for reconstruction of an insufficient, short first ray due to loosening of an endoprosthesis, osteomyelitis or after a Keller procedure. Patients and Methods: In a retrospective study we evaluated the outcome of 15 patients with a mean age of 62 years, who underwent an interpositional arthrodesis of the first MTP joint. Correction of the deformity was achieved by osteotomy of the tricortical bone graft. Osteosynthesis was performed by use of screw fixation alone or by combined screw, plate and K-wire fixation. Postoperatively patients were mobilised for 10 weeks in a forefoot off loading shoe. Clinical and radiological examination was performed 10 weeks postoperatively. Radiological parameters such as hallux valgus angle, MTP dorsiflexion angle and the graft size were measured. In all patients pre- and postoperatively, the intensity of pain (VAS), the overall satisfaction with the procedure and the American orthopaedic foot and ankle score (AOFAS score) were evaluated. Results: The mean follow-up was 26 months (range 4-48 months). The mean pain intensity measured with the VAS was reduced from 7.5 preoperatively to 0.5 postoperatively. In 14 patients fusion of the arthrodesis was achieved at a mean of 12 weeks. One patient developed a pseudarthrosis which was effectively treated by extracorporeal shockwaves. Postoperatively radiological measurements demonstrated a mean hallux valgus angle of 16° (range 6-28°), a mean MTP dorsiflexion angle of 17° (range 12-27°) and a mean graft size of 16 mm (range 10-30 mm). The mean AOFAS score improved from 26 preoperatively to 81 postoperatively. All but 1 patient were satisfied with the final outcome and achieved free mobility. Conclusions: Interpositional arthrodesis of the first MTP joint achieves good clinical and radiological results with a high level of patient satisfaction in patients with an insufficient and short first ray of the foot. PMID:24129722

Waldecker, U



Generation of Application Level Audit Data via Library Interposition  

Microsoft Academic Search

One difficulty encountered by intrusion and misuse detection systems is a lack of application level audit data. Frequently, applications used are written by third parties and may be distributed only in a binary format. In this paper we present a technique to generate application level audit data using library interposition. Interposition allows the generation of audit data without needing to

Benjamin A. Kuperman; Eugene Spafford



Shoulder arthroplasty  

Microsoft Academic Search

Shoulder prostheses are now commonly used. Clinical results and patient satisfaction are usually good. The most commonly used\\u000a types are humeral hemiarthroplasty, unconstrained total shoulder arthroplasty, and semiconstrained inversed shoulder prosthesis.\\u000a Complications of shoulder arthroplasty depend on the prosthesis type used. The most common complications are prosthetic loosening,\\u000a glenohumeral instability, periprosthetic fracture, rotator cuff tears, nerve injury, infection, and deltoid

Florian M. Buck; Bernhard Jost; Juerg Hodler



Patellofemoral arthroplasty.  


Isolated patellofemoral arthritis can occur in as many as 9% of patients older than 40 years and is particularly common in women, who often have subtle patellofemoral maltracking or malalignment. In fact, 24% of women with symptomatic knee arthritis have localized patellofemoral arthritis. Arthroplasty options can provide predictable pain relief, whereas other surgical measures for refractory patellofemoral arthritis--arthroscopic debridement, cartilage grafting, patellectomy, tibial tubercle unloading procedures--often have unsatisfactory results. While total knee arthroplasty (TKA) yields excellent results in >90% of patients with isolated patellofemoral arthritis, it is not desirable in patients who are young and active. Therefore, patellofemoral arthroplasty has a legitimate role in the treatment of isolated anterior compartment arthritis. Early patellofemoral implants were plagued by a high incidence of patellar maltracking, catching and subluxation, due to design features of the trochlear components, inadequate soft tissue balancing, and component malposition. Most importantly, contemporary onlay style trochlear components, implanted perpendicular to the anteroposterior axis of the femur, have substantially reduced the patellar maltracking that was so prevalent with inlay style prostheses for 3 decades. With onlay trochlear designs, early patella instability problems have been reduced, leaving late tibiofemoral degeneration as the primary cause of failure of patellofemoral arthroplasties. Several long-term studies have shown a rate of tibiofemoral degeneration of approximately 20% at 15 years. Finally, the results of TKA do not seem to be compromised by the presence of a prior patellofemoral arthroplasty. PMID:20839682

Lonner, Jess H



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

Code of Federal Regulations, 2013 CFR

... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3970 Interarticular disc prosthesis (interpositional implant). (a) Identification. An...



Compliance in Anastomoses With and Without Vein Cuff Interposition  

Microsoft Academic Search

Objective to compare anastomotic compliance in end-to-side anastomoses with and without vein cuff interposition. Materials polytetrafluoroethylene graft to bovine carotid artery without (standard) and with vein interposition (Linton-patch and Miller-cuff). Methods zonewise compliance measurement of end-to-side anastomoses in anin-vitro circulation system. The zone most distal to the suture-line served as reference compliance. Resultsdirectly distal to the suture-line the compliance of

D. Piorko; P. Knez; K. Nelson; T. Schmitz-Rixen



Patellofemoral Arthroplasty  

Microsoft Academic Search

Isolated arthritis on the patellofemoral articulation has received minimal attention in the past. It is now recognized to be relatively common, especially in women. Treatment alternatives such as patellectomy, unloading osteotomies, debridement, and cartilage transplant have not offered long-term sustainable benefits. Therefore, there is a need for a reliable patellofemoral arthroplasty. The current indications for surgery include middle-aged patients with

Paul A. Lotke; Jess H. Lonner; Charles L. Nelson



The modified Zancolli arthroplasty for basal thumb arthritis.  


The modified Zancolli arthroplasty for basal thumb arthritis is an alternative to different procedures described for this pathology. As most of the methods, it includes complete trapeziectomy. The main difference is that the interposition is made with capsule (resembling Colonna's method for the hips) and that the base of the metacarpal is stabilized in the correct place by a tendon transfer (performed with an accessory of abductor pollicis longus). The main advantage of this method is the short immobilization time (2 wk) and high percentage (95%) of complete pain-free results and a stable and strong thumb in key pinches. PMID:21107225

Zancolli, Eduardo R; Andrés, Bernardo Gustavo



Comparison of incus interpositioning technique versus glass ionomer cement application in type 2 tympanoplasty.  


Objective of this study is to compare glass ionomer cement application and incus interpositioning techniques in patients who have chronic otitis media, conductive hearing loss with intact tympanic membrane and who undergo hearing reconstruction of staged surgery using a retrospective chart review in the setting of Ministry of Health Ankara Training and Research Hospital ENT Clinic, Turkey. We retrospectively evaluated patients who underwent otological surgery and hearing reconstruction with auto graft incus during 2005-2008 or glass ionomer cement during 2008-2010. Patients who had cholesteatoma, stapes fixation and tympanosclerosis were excluded. Postoperative mean follow-up time of 107 patients was 9.8 months (6-38 months, 83.2 % of them was ? 9 months). Postoperative pure tone hearing thresholds, graft status, gain scores and air bone gaps were recorded. Intact graft, dry ear on the operated side and ABG scores less than 20 dB were accepted as surgical success. Preoperative ABG score was 30.6 ± 7.93 dB in glass ionomer (group I) and 33.6 ± 11.99 dB in incus interpositioning (group II). Postoperative ABG scores were 13.6 ± 10.40 and 22.6 ± 12.39 dB, respectively, in group I and II. Success of closure in ABG scores was obtained in both groups (p < 0.001). Gain scores in group I were better (p = 0.035). Graft success (p = 0.020) correlated with gain score. Results showed that the glass ionomer cement application is a good, cost-effective technique, easy to perform and yields better hearing scores and lower complication rates compared to incus interpositioning technique. PMID:23010791

Yaz?c?, Ha?met; Uzunkulao?lu, Hakk?; Emir, Hatice Karadas; K?z?lkaya, Zeynep; Do?an, Sedat; Samim, Erdal



The effect of isoperistaltic jejunal interposition upon gastric emptying  

SciTech Connect

Ten patients with severe postgastrectomy-postvagotomy symptoms, all of whom had the features of vasomotor dumping, underwent gastric emptying studies, using a 300 milliliter meal of 15 per cent dextrose labeled with 99mTc-sulphur colloid. Studies were repeated two to 11 months following remedial operative treatment, using a 12.5 to 15.0 centimeter isoperistaltic jejunal interposition. Preoperatively, all patients had rapid gastric emptying with a typical biphasic pattern. Following isoperistaltic interposition, the rate of gastric emptying was similar to that found in control patients. Gastric emptying reverted to a more normal pattern but, as in the preoperative studies, was best described by a double exponential function, consisting of slow and fast components. Analysis of these particular functions suggests the manner in which isoperistaltic interposition modified the underlying disorder of gastric motility.

Mackie, C.R.; Hall, A.W.; Clark, J.; Wisbey, M.; Baker, P.R.; Cuschieri, A.



Incomplete seating of a metal-backed alumina liner in ceramic-on-ceramic total hip arthroplasty.  


Metal-backed modular ceramic bearing systems using a recessed alumina liner in a titanium sleeve were developed to decrease ceramic chipping or fracture due to femoral neck impingement after total hip arthroplasty (THA). However, malseating of the metal-backed ceramic liner has recently been described. The goal of this study was to assess the prevalence, etiology, and clinical relevance of this event. Between 2005 and 2008, 51 consecutive patients (61 hips) underwent THA with a metal-backed alumina liner housed in a titanium shell. The metal-backed ceramic liner was aligned, seated, and impacted into the shell, and satisfaction in terms of liner stability and seating was confirmed intraoperatively. Postoperative assessment of seating was assessed with standard radiographs. Liner seating was classified as well seated, suspicious, or malseated. Seven liners (11.5%) were found to be malseated and 4 (6.5%) were considered suspicious. Radiographically, there was a gap between the liner and the shell located inferomedially in 4 patients and superolaterally in 3 patients. Two liners subsequently seated at 1 and 3 months postoperatively, respectively. No dislodgement, failures, or adverse events were identified. There were no revision surgeries. The significant percentage of malseated liners were potentially attributed to poor exposure, bony/soft tissue interposition, and surgeon learning curve. PMID:20055343

Carvajal Alba, Jaime A; Schiffman, Eric D; Scully, Sean P; Parvataneni, Hari K



Comparison of glass ionomer cement and incus interposition in reconstruction of incus long process defects.  


The ossicles may be affected through the mass effect of the pathological tissue in chronic otitis media. Ossicular reconstruction may be accomplished using the patients' own ossicles or with alloplastic materials. Glass ionomer ossiculoplasty is a fast, efficient, safe and cost-effective method and it has been used more frequently in recent years. Forty-six patients who had surgery for chronic otitis media were included in this study. All patients had an incus long process defect and a normal stapes superstructure. Ossicular reconstruction was performed using glass ionomer cement (GIC) (Ketac-Cem, Espe Dental AG, Seefeld, Germany) in 23 patients (group 1), while incus interposition was performed in other 23 patients (group 2). Preoperative and postoperative air pure tone averages of the group 1 patients were 42.8 and 35.2 dB, respectively (p < 0.01). These values were 42.9 and 34.5 dB in group 2 (p < 0.01). Two groups were similar with respect to postoperative hearing gain (p > 0.05). The air bone gap of group 1 was 27 dB preoperatively and 20.7 dB postoperatively. These values were 28.7 and 20.2 dB, respectively, in group 2. The closure of air bone gap was statistically significant in both the groups (p < 0.01, p < 0.01). The comparison of the mean gains of the air bone gap revealed no difference between the groups (p > 0.05). In conclusion, the use of both GIC ossiculoplasty and incus interposition are efficient methods for reconstruction of incus long process and one is not superior to the other. A larger study population may be useful for comparison of these methods. PMID:21340562

Dere, Huseyin; Ozdogan, Fatih; Ozcan, K Murat; Selcuk, Adin; Ozcan, Ibrahim; Gokturk, Gokhan



Trapezium prosthetic arthroplasty (silicone, Artelon, metal, and pyrocarbon).  


Trapezium prosthetic arthroplasty has been utilized to treat basal joint arthritis for nearly five decades in an attempt to mitigate some of the potential disadvantages of trapeziectomy while preserving range of motion. Implant arthroplasty seeks to preserve joint biomechanics, avoids metacarpal subsidence, and should provide immediate stability. These benefits may lead to improvements in strength, durability, and a decrease in metacarpophalangeal joint hyperextension which can occur subsequent to metacarpal shortening. First generation implants were primarily silicone trapezial spacers. While the use of these implants has been curtailed by their association with silicone synovitis, they still remain an option for low demand, rheumatoid patients. More recently developed synthetic spacers such as Artelon interposition arthroplasties have had results inferior to more established procedures including trapeziectomy. A variety of metal total joint prostheses have been developed and some of the more recent designs have shown good short-term outcomes. There are a number of different pyrocarbon implants that have become more recently available which range from trapezial substitution to non-anatomic hemiarthroplasty. Pyrocarbon arthroplasty offers a number theoretical advantages however early results have been mixed and further long term data is required. PMID:23168027

Vitale, Mark A; Taylor, Fraser; Ross, Mark; Moran, Steven L



Accuracy of soft tissue balancing in total knee arthroplasty  

Microsoft Academic Search

To the best of our knowledge, this is the first study to assess the accuracy of balancing of the flexion and extension gaps in total knee arthroplasty (TKA). Measurements of the heights of the flexion and extension gaps were obtained during 104 consecutive primary, posterior-stabilized TKAs in osteoarthritic patients. Clinically, all knees appeared to be well balanced intraoperatively. Rectangular flexion

Frankie M. Griffin; John N. Insall; Giles R. Scuderi



[Foreign body reaction in osteoarthritis of the trapeziometacarpal joint treated by trapezectomy and interposition of a L-polylactic acid "anchovy" (Arex®615R). A series of eight cases].  


Osteoarthritis of the trapeziometacarpal joint is a common pathology. When the trapezium is not large enough to allow using a total joint arthroplasty or in case of peritrapezial osteoarthrosis, the authors used a trapeziectomy with interposition of an absorbable L-polylactic acid anchovy (Arex(®)615R). This technique is simple and fast. From 2006 to 2010, out of 68 implants, nine displayed a prolonged inflammatory reaction, both clinically and radiologically abnormal, leading the patients to undergo revision surgery for removal of the implant before the end of the third postoperative year. Histological analysis highlighted in all the cases a resorptive gigantocellular immune foreign body reaction. PMID:23665309

Semere, A; Forli, A; Corcella, D; Mesquida, V; Loret, M G; Moutet, F



Colon Interposition in Children after Failed Tracheoesophageal Fistula Repair  

PubMed Central

The most common surgical procedure used to manage tracheoesophageal fistula is the primary anastomosis of the esophagus. However, in the case of failed anastomosis, replacing the esophagus with another organ is necessary. We performed two procedures of colon interposition after failure of tracheoesophageal fistula repair. In those cases, stomach replacement was not possible because of a failed Ivor Lewis operation in one case and duodenal atresia in the other.

Park, Samina; Kim, Hye-Seon; Park, In Kyu; Kim, Young Tae; Kim, Joo-Hyun



Fibrin glue as interposition graft for tarsal coalition.  


We describe a surgical technique and report outcomes for fibrin glue interposition after resection of a tarsal condition. An institutional review board--approved retrospective review of all pediatric patients with a tarsal coalition managed with resection was conducted between January 2002 and July 2010 by a single surgeon. All coalitions were resected with interposition of fibrin glue. Patients were evaluated for postoperative complications, pain, weight-bearing status, return to sports, and ankle and subtalar range of motion. Six feet without a coalition were used as a control group. Nine patients (12 feet) were identified with mean follow-up of 2.1 years (range, 7-72 months). Pre-operative complaints were predominantly foot and ankle pain. Patients also reported flatfeet and recurrent ankle sprains. There were no reported postoperative complications. All 9 patients were weight-bearing as tolerated and returned to sports by 6 months. Fibrin glue is a safe and reliable alternative to tissue grafts for interposition after resection of a tarsal coalition. PMID:23431536

Weatherall, Justin M; Price, Andrew E



Capsular interposition for the Keller bunionectomy with the use of soft-tissue anchors.  


The Keller procedure has been used during the past century for the treatment of first metatarsophalangeal joint pathology. Many modifications to the procedure have been made, including interposition of the joint capsule into the first metatarsophalangeal joint space. Capsular interposition is often the most difficult step in performing the Keller bunionectomy. This article describes a new, simplified technique for capsular interposition with the use of a dorsal capsular flap and soft-tissue anchors. PMID:15778479

Cook, Keith D


Biomechanics of lumbar arthroplasty.  


There are many issues to consider in evaluating the biomechanics of lumbar arthroplasty, which may consist of a nucleus replacement, a total disc replacement, or a mobile posterior device. The goal of spinal arthroplasty is to replicate or augment the function of the normal spinal elements, by taking into consideration both in the quantity and quality of motion that occurs across the replaced joint. This article describes the relevant parameters for studying the biomechanics of lumbar arthroplasty and briefly summarizes the current knowledge with regard to those parameters in some well-known lumbar nucleoplasty, facet replacement, and total disc arthroplasty devices. PMID:16326282

Crawford, Neil R



Surface replacement trapeziometacarpal joint arthroplasty--early results.  


This study reviews the results of Surface Replacement Trapeziometacarpal (SR TMC, Avanta, San Diego, CA) total joint arthroplasty. Fifty patients (62 joints) were included in the study. Forty-three patients (54 joints) were seen at final follow up. Seven patients (eight joints) were interviewed over the phone. Seven patients were revised to trapeziectomy and ligament reconstruction with tendon interposition, five for aseptic loosening and two for dislocation. At final follow up, the mean Quick DASH score was 30.4 and the Sollerman Score was 77.3. Radiological review of the surviving 55 joints showed subsidence of four trapezial components in asymptomatic patients. Cumulative survival rate was 91% at 3 years. Eighty-five percent of the patients were satisfied with the outcome of their treatment. PMID:19786406

Pendse, A; Nisar, A; Shah, S Z; Bhosale, A; Freeman, J V; Chakrabarti, I



Total hip arthroplasty.  

PubMed Central

Total hip arthroplasty, or surgical replacement of the hip joint with an artificial prosthesis, is a reconstructive procedure that has improved the management of those diseases of the hip joint that have responded poorly to conventional medical therapy. In this review we briefly summarize the evolution of total hip arthroplasty, the design and development of prosthetic hip components, and the current clinical indications for this procedure. The possible complications of total hip arthroplasty, its clinical performance over time, and future directions in hip replacement surgery are also discussed. Images

Siopack, J S; Jergesen, H E



Imaging of hip arthroplasty.  


The imaging evaluation of the prosthetic hip begins with radiography, but arthrography, aspiration, scintigraphy, sonography, CT and MR imaging all have roles in the evaluation of the painful prosthesis. This article will review the appearance of normal hip arthroplasty including hemiarthroplasty, total arthroplasty, and hip resurfacing, as well as the appearances of potential complications such as aseptic loosening and osteolysis, dislocation, infection, periprosthetic fracture, hardware failure, and soft tissue abnormalities. PMID:21530121

Miller, Theodore T



An Evaluation of Jejunal Interposition Reconstruction after Total Gastrectomy in Dogs.  

National Technical Information Service (NTIS)

The operation of jejunal interposition reconstruction after total gastrectomy in dogs was compared with more standard end-to-side esophagojejunostomy and Roux-en-Y procedures. Weight loss; digestive impairment; microcytic, anemia; and poor iron absorption...

D. W. Lawson A. J. Defalco B. E. Bradley G. C. Vineyard J. E. McClenathan



Imaging of hip arthroplasty.  


Imaging studies are central to the evaluation of persistent or recurrent symptoms after hip arthroplasty. The evaluation starts with radiographs and may be followed by arthrography, aspiration, scintigraphy, sonography, computed tomography, and MR imaging. Common etiologies of a painful or dysfunctional hip arthroplasty are mechanical loosening, polyethylene wear-induced osteolysis, adverse local tissue reaction to metal wear products, infection, fractures, heterotopic ossification, tendinopathy, and nerve injury. MR imaging with optimized protocols and dedicated techniques for metal artifact reduction is the most comprehensive imaging modality. In this article, we discuss and illustrate the imaging appearances of these conditions with a focus on the MR imaging evaluation. PMID:23787986

Fritz, Jan; Lurie, Brett; Miller, Theodore T



Prospective Single-Arm, Multi-Center Trial of a Patient-Specific Interpositional Knee Implant: Early Clinical Results  

PubMed Central

Background: The treatment of unicompartmental arthritis in younger patients is challenging. The aim of this study is to report final safety and efficacy analysis results for the iForma patient–specific interpositional device, which is designed for the treatment of isolated medial or lateral compartment arthritis of the knee. Methods: From June 2005 to June 2008 78 subjects (42 men, 36 women) received an iForma implant. The mean age was 53 years, the mean Body Mass Index 29.0. We surveyed the WOMAC scores, the visual analog pain scale and the Knee Society Scores. Results: The mean follow up was 16.4 months. The mean WOMAC knee scores increased from 48.3 before surgery to 71.3 after 24 months. A reduction in pain was achieved for all five pain measures using a standard visual analog scale (VAS). Knee Society Knee Score improved from 39.2 before to 61.9 24 month after surgery. The Knee Society Function Scores improved form preoperative 64.5 to 82.5 2 years postoperative. The preoperative range of motion could be restored. The overall revision rate was 24%. 15 implants were removed early, 4 knees were revised without implant removal. Conclusion: Within narrow indication of patients with unicompartmental disease, the iForma device can provide improvement in knee function and reduction in pain, however, with a significant higher risk of early revision compared to traditional arthroplasty. Respecting this limitation it may be an alternative option for arthritic patients with unicompartmental disease who have contraindications to High Tibial Osteotomy or are too young for knee replacement; the iForma device further has the distinct advantage of time and cost saving compared to those procedures.

Koeck, F.X; Luring, C; Goetz, J; Handel, M; Tingart, M; Grifka, J; Beckmann, J



Periprosthetic total knee arthroplasty fractures: revision arthroplasty technique.  


With increased use of total knee arthroplasty (TKA) technique, the burden of revision surgery for all causes including periprosthetic fractures is anticipated to increase substantially in the coming decades. Although periprosthetic TKA fractures are most frequently managed with operative repair, there are circumstances where fracture characteristics or patient factors may make a revision total knee arthroplasty more preferable. This article outlines the principles of surgical treatment when a revision arthroplasty technique is selected. PMID:23393055

Keeney, James A



Emptying of the gastric substitute after total gastrectomy. Jejunal interposition versus Roux-y esophagojejunostomy.  


Emptying of the gastric substitute and small bowel transit time of a 99mTc-labeled solid test meal were measured in 20 tumor-free patients 13 to 63 (median, 35) months after total gastrectomy with Roux-y (n = 11) and jejunal interposition (n = 9) reconstruction. The emptying half-times ranged from 2 minutes to greater than 20 minutes. Rapid emptying was associated with dumping symptoms (p less than 0.03) and shorter orocoecal transit-time (p less than 0.05). Serum glucose concentrations rose more quickly in jejunal interposition, but the areas under the curve were identical in both groups. The median insulin-to-glucose ratio (areas under the curve) during the 20 minutes after the meal was 11.4 in jejunal interposition and 7.1 in Roux-y esophagojejunostomy (NS). Interposition cases had regained a significantly higher percentage (89%) of their premorbid weight than patients with Roux-y (78%; p less than 0.05). The weight/height2 ratio was above the 50th centile in 45% of interpositions, but below the 50th centile in all patients after the Roux-y mode of reconstruction (p less than 0.05). It is concluded that the emptying velocity of the gastric substitute has no impact on postoperative weight gain. The authors contend that the concept of a gastric substitute pouch is not supported by the findings of this study. PMID:2667472

Miholic, J; Meyer, H J; Kotzerke, J; Balks, J; Aebert, H; Jähne, J; Weimann, A; Pichlmayr, R



A Comparison of Interposition and Femoropopliteal Bypass Grafts in the Management of Popliteal Artery Trauma  

PubMed Central

Background: Peripheral vascular injury associated with lower limb trauma is a well-known emergency. The experience for the management of popliteal artery trauma have mainly come from managing the traumas of military personnels during Iran-Iraq war. The present study compared the effects of two currently-used surgical techniques in the management of popliteal trauma, namley femoropopliteal bypass graft and interposition vein graft on limb salvage. Methods: A retrospective review of 40 patients with popliteal artery trauma admitted to the trauma unit of a university teaching hospital during 2003 to 2008. The patients had undergone femoropopliteal bypass graft (n=26) or interposition vein graft (n=14) for the management of popliteal trauma. Results: The amputation rate among patients managed by femoropopliteal bypass or interposition vein graft was 35.7% and 61.5%, respectively. Knee stability among patients managed by interposition graft group was 57.7% and in those managed by femoropopliteal bypass graft was 85.7%. Conclusion: The rates of knee stability achieved by the employed techniques indicate that femoropopliteal bypass vein graft is superior, and therefore, preferable to the interposition vein graft in the management of popliteal artery trauma.

Mohammadzade, Mohammad Ali; Mohammadzade, Maryam; Herfatkar, Mohammad Rasul



Complications of wrist arthroplasty.  


Total wrist arthroplasty is an alternative for patients with severe wrist arthritis who have specific requirements or desires to preserve motion. However, wrist replacement has its own unique risks and potential complications, and is not appropriate for patients with high physical demands. This article discusses these risks and complications and provides strategies to minimize risks and manage complications. PMID:20494747

Adams, Brian D



Anterior cruciate ligament arthroplasty  

Microsoft Academic Search

A unique augmentation arthroplasty has evolved from a retrospective review of 150 anterior cruciate ligament (ACL) repairs, extracapsular substitutions, and pes an serine transfers. This coincided with a proposed patho logic relationship seen in surgical exposures of the femoral intercondylar notch. From 1976 to 1983, 544 cases with known ACL insufficiency were selected for study. In 397 subsequent anterior cruciate

David A. Kieffer; Robert J. Curnow; Richard B. Southwell; William F. Tucker; Katherine K. Kendrick



Patellofemoral Arthroplasty: Current Concepts  

Microsoft Academic Search

Patellofemoral arthroplasty can be considered for iso- lated chondral degeneration of the anterior compartment of the knee. Successful results may be achieved with careful patient se- lection, meticulous surgical technique, use of an implant of sound design, and modification of patient activities in the postoperative period.



A comparison of vas occlusion techniques: cautery more effective than ligation and excision with fascial interposition  

PubMed Central

Background Vasectomy techniques have been the subject of relatively few rigorous studies. The objective of this analysis was to compare the effectiveness of two techniques for vas occlusion: intraluminal cautery versus ligation and excision with fascial interposition. More specifically, we aimed to compare early failure rates, sperm concentrations, and time to success between the two techniques. Methods We compared semen analysis data from men following vasectomy using two occlusion techniques. Data on intraluminal cautery came from a prospective observational study conducted at four sites. Data on ligation and excision with fascial interposition came from a multicenter randomized controlled trial that evaluated the efficacy of ligation and excision with versus without fascial interposition. The surgical techniques used in the fascial interposition study were standardized. The surgeons in the cautery study used their customary techniques, which varied among sites in terms of type of cautery, use of fascial interposition, excision of a short segment of the vas, and use of an open-ended technique. Men in both studies had semen analyses two weeks after vasectomy and then approximately every four weeks. The two outcome measures for the analyses presented here are (a) time to success, defined as severe oligozoospermia, or <100,000 sperm/mL in two consecutive semen analyses; and (b) early vasectomy failure, defined as >10 million sperm/mL at week 12 or later. Results Vasectomy with cautery was associated with a significantly more rapid progression to severe oligozoospermia and with significantly fewer early failures (1% versus 5%). Conclusion The use of cautery improves vasectomy outcomes. Limitations of this comparison include (a) the variety of surgical techniques in the cautery study and differences in methods of fascial interposition between the two studies, (b) the uncertain correlation between sperm concentrations after vasectomy and the risk of pregnancy, and (c) the use of historical controls and different study sites.

Sokal, David; Irsula, Belinda; Chen-Mok, Mario; Labrecque, Michel; Barone, Mark A



Shoulder and elbow arthroplasty in younger patients.  


Joint arthroplasty is common in elderly patients with arthritis. The success of joint arthroplasty in the elderly population has increased the indications for joint arthroplasty in younger patients. The success and increased indications are due to advances in technology and joint arthroplasty design and materials, as well as to bone-conserving approaches that are more applicable to younger patients. Although most joint arthroplasty procedures are for the hip and knee, the upper extremity (shoulder and elbow) is the fastest-growing segment of joint arthroplasty procedures. This article presents innovative approaches to shoulder and elbow arthroplasty that are designed to treat younger patients with arthritis of the shoulder and elbow. PMID:23445859

Packer, Jonathan D; Blaine, Theodore A



Modified total trapezial and partial trapezoidal excision and ligament reconstruction tendon interposition reduces symptoms in isolated scaphotrapezial-trapezoid arthritis of the wrist.  


Trapezial excision arthroplasty with ligament reconstruction and tendon interposition (LRTI) modified to include proximal trapezoid excision was performed on 12 wrists in 10 patients with symptomatic, isolated scaphotrapezial-trapezoid (STT) arthritis. Wrist range of motion, lateral pinch and grip strength, and analog pain scores were measured pre- and post-operatively. Mean follow-up was 18 (11-42) months. Post-operatively, reported pain scores uniformly decreased (p < 0.0001). Mean range of wrist flexion increased from 48 to 53° (p < 0.05) and extension from 51 to 55° (p < 0.05). There was also an overall increase in mean grip strength from 15.6 to 19.2 kg and pinch strength from 3.5 to 4.3 kg. Modified Mayo Wrist Scores were excellent in six cases, good in three, and fair in one. Our results suggest that modified total trapezial, partial trapezoidal excision and LRTI could be an effective surgical alternative in cases of isolated STT arthritis. PMID:22570323

Andrachuk, J; Yang, S S



Revision Patellofemoral Arthroplasty  

Microsoft Academic Search

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

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



Unconstrained knee arthroplasty after patellectomy.  


The authors report seven cases of unconstrained knee arthroplasty with excision of both cruciate ligaments, after previous patellectomy. Six of these seven cases were completely painfree and function was satisfactory in all cases. The reasons for previously reported pain and instability after total unconstrained knee arthroplasty with excision of the cruciate ligaments and a previous patellectomy are discussed. PMID:2230822

Railton, G T; Levack, B; Freeman, M A



Arthroplasty of a Charcot knee  

PubMed Central

The Charcot knee - or neuropathic arthropathy - presents a considerable challenge to the orthopaedic surgeon. Caused by a combination of sensory, motor and autonomic neuropathy, it was originally described as an arthritic sequelae of neurosyphilis. In today's western orthopaedics it is more often caused by diabetes. A Charcot knee is often symptomatically painful and unstable. Traditional management has usually been conservative or arthrodesis, with limited success. Arthroplasty of a Charcot joint has commonly been avoided at all costs. However, in the right patient, using the right technique, arthroplasty can significantly improve the symptoms of a Charcot joint. This article explores the evidence surrounding the role of arthroplasty in the management of a Charcot knee. Arthroplasty is compared to other forms of treatment and specific patient demographics and surgical techniques are explored in an attempt to define the role of arthroplasty in the management of a Charcot knee.

Babazadeh, Sina; Stoney, James D.; Lim, Keith; Choong, Peter F.M.



Left ventriculo-colic fistula--a late complication of colonic interposition for the oesophagus  

Microsoft Academic Search

An 18 year old man developed recurrent haematemesis 12 years after colonic interposition for corrosive injury to the oesophagus. A colonic ulcer close to the cologastric anastomosis appeared to have fistulated into the cavity of the left ventricle. This so far unreported complication needs to be considered when patients who have had coloesophageal substitution present with gastrointestinal bleeding.

M. L. Pantelides; M. D. Fitzgerald



Occult interpositional rotator cuff - an extremely rare case of traumatic rotator cuff tear.  


Traumatic interposition of a rotator cuff tendon in the glenohumeral joint without recognizable glenohumeral dislocation is an unusual complication after shoulder trauma. Here we report the clinical and imaging presentations of a 17-year-old man with trapped rotator cuff tendons in the glenohumeral joint after a bicycle accident. The possible trauma mechanism is also discussed. PMID:22247643

Lin, Cheng-Li; Su, Wei-Ren; Jou, I-Ming; Chih, Wei-Hsing



Occult Interpositional Rotator Cuff - an Extremely Rare Case of Traumatic Rotator Cuff Tear  

PubMed Central

Traumatic interposition of a rotator cuff tendon in the glenohumeral joint without recognizable glenohumeral dislocation is an unusual complication after shoulder trauma. Here we report the clinical and imaging presentations of a 17-year-old man with trapped rotator cuff tendons in the glenohumeral joint after a bicycle accident. The possible trauma mechanism is also discussed.

Lin, Cheng-Li; Su, Wei-Ren; Jou, I-Ming



Reverse shoulder arthroplasty.  


The reverse shoulder arthroplasty is considered to be one of the most significant technological advancements in shoulder reconstructive surgery over the past 30 years. It is able to successfully decrease pain and improve function for patients with rotator cuff-deficient shoulders. The glenoid is transformed into a sphere that articulates with a humeral socket. The current reverse prosthesis shifts the center of rotation more medial and distal, improving the deltoid's mechanical advantage. This design has resulted in successful improvement in both active shoulder elevation and in quality of life. PMID:23827841

Jarrett, Claudius D; Brown, Brandon T; Schmidt, Christopher C



Activity Scale for Arthroplasty Patients After Total Hip Arthroplasty  

Microsoft Academic Search

The purpose of the Activity Scale for Arthroplasty Patients (ASAP) is to develop and validate a self-report questionnaire that demonstrated discrimination of functional gains, low burden, appropriate concurrent validity, and was not limited by ceiling effects. We identified 128 high-functioning hip arthroplasty patients from our database who completed a 25-item ASAP and Lower Extremity Functional Scale questionnaires and a set

Taymon Domzalski; Chad Cook; David E. Attarian; Scott S. Kelley; Michael P. Bolognesi; Thomas P. Vail




Microsoft Academic Search

Twenty-three patients who had undergone trapeziectomy and Helal silicone rubber ball interposition for trapeziometacarpal arthritis were reviewed. The average age at operation was 63 (range 48–84) years and the mean follow-up was 59 (range 12–138) months. Of the 23 patients reviewed, two had pain at rest and four had some discomfort on exertion. Mean post-operative thumb extension was 37° whilst




Complications of small joint arthroplasty.  


Arthritis in the small joints of the hand can be treated with arthrodesis or arthroplasty. Arthrodesis has known risks of infection, pain, and nonunion. Distal interphalangeal (DIP) arthroplasty has been successful in preserving motion and alleviating pain for distal DIP, proximal interphalangeal, and metacarpophalangeal joints. Unfortunately, complications arise that limit the success of surgery. Silicone implants have been reliable for many years but still present with the risks of infection, implant breakage, stiffness, and pain. Newer implant designs may limit some of these complications, but present with unique problems such as dislocations and loosening. It is not yet clear as to which type of implant provides the most reliable results, although implant arthroplasty appears to give better function than arthrodesis. Silicone arthroplasty does not lead to silicone synovitis and is a reliable procedure. Pyrocarbon implants are showing some promise, particularly in the osteoarthritic patient. PMID:20494746

Drake, Matthew L; Segalman, Keith A



Sports After Hip Resurfacing Arthroplasty  

Microsoft Academic Search

Background: No information is available concerning patients' sports activity after hip resurfacing arthroplasty.Hypothesis: Patients treated by hip resurfacing arthroplasty will be able to achieve a high level of sports activity.Study Design: Case series; Level of evidence, 4.Methods: We surveyed 112 patients by postal questionnaire to determine their sporting activities at a mean of 23.5 (range, 9—40) months after hip resurfacing

Florian-D. Naal; Nicola A. Maffiuletti; Urs Munzinger; Otmar Hersche



Does Arthroscopic Débridement With or Without Interposition Material Address Carpometacarpal Arthritis?  


BACKGROUND: Thumb carpometacarpal (CMC) joint arthritis is a common problem in clinical practice with a variety of treatment options. Arthroscopic procedures can preserve all or part of the trapezium in the setting of treatment of basilar joint arthritis, and such procedures (even without stabilization or ligament reconstruction) have high reported success rates. However, little is documented about the limitations of these procedures in terms of patient selection, the optimal type of interposition, if any, and rehabilitation. QUESTIONS/PURPOSES: A systematic review was performed to determine the influence of (1) interposition material (manufactured, biological, or none); and (2) patient-related factors (including metacarpophalangeal joint hyperextension, ligamentous laxity, and severity of arthritis) on pain, functional scores, and postoperative complications unique to each approach. METHODS: A systematic review of the English language literature regarding thumb basilar joint arthritis and arthroscopic partial trapeziectomy or débridement was performed. Those procedures including ligament reconstruction or stabilization were excluded. RESULTS: Biological materials and no interposition were both associated with satisfactory improvement and low rates of complications; complication rates with synthetic materials were higher. Eaton Stages I to III were treated successfully with this technique. The effect of scaphotrapeziotrapezoid (STT) changes was variably described across series. In most series, metacarpophalangeal hyperextension did not seem to have an adverse effect on outcomes, although these patients were excluded in some series. CONCLUSIONS: Arthroscopic débridement with or without interposition can be used for treatment of Eaton Stages I to III CMC osteoarthritis with satisfactory outcomes. Some series suggest satisfactory outcomes in the setting of STT changes and metacarpophalangeal hyperextension. PMID:23479236

Adams, Julie E



Using inter-positional Transfer Functions in 3D-sound  

Microsoft Academic Search

This paper addresses the interpolation of Head-Related Transfer Functions (HRTFs) for 3D-sound generation through headphones. HRTFs are transfer functions associated with the paths between sound sources and the ears, and are usually measured for a finite set of source locations around the listener. Generation of 3D-sound at any other virtual positions requires interpolation procedures. In this work, the Inter-positional Transfer

L. W. P. Biscainho; F. P. Freeland; P. S. R. Diniz



Comparing reconstruction with ileocecal graft to jejunal interposition pouch after total gastrectomy in rats.  


After total gastrectomy, the ileocecal graft may act as a reservoir and protect against reflux but give rise to transposition of the ileum and cause possible changes in bile acid metabolism and nutrition. This study compared the ileocecal graft and jejunal pouch. Male Wistar rats weighing 265 +/- 22 g were submitted to sham operation (S), ileocecal interposition graft (IIG), and jejunal pouch interposition graft (JP) after total gastrectomy. Eight weeks later, the esophagus was examined for evidence of esophagitis. Nutritional biochemistry and weight profile were documented preoperatively and 8 weeks after surgery. The oral glucose tolerance test was performed. Thirty-three rats were operated on and 30 survived for 8 weeks. Esophagitis occurred in seven JP rats. Body weight was significantly higher in IIG than in JP rats (p < .05). Normal glucose tolerance to intragastric glucose load was observed in sham and operated rats. JP rats had a significant decrease in serum albumin, glucose, transferrin, hemoglobin, iron, folate, and calcium, compared to sham (p < .05). Cobalamine was significantly lower in IIG rats than in JP rats (p < .05). In the IIG and JP groups, serum/hepatic total bile acid did not differ significantly from preoperative and sham values. In conclusion, the IIG interposition graft in rats prevented esophagitis, preserved nutrition, and did not interfere with enterohepatic total bile acid circulation. PMID:17365406

Medeiros, Aldo Cunha; Filho, Irami Araújo; Medeiros, Vítor Brasil; Pinheiro, Laíza Araújo Mohana; Freire, Flávio Henrique Miranda Araújo; Azevedo, Italo Medeiros; Brandão-Neto, José


Sliding reconstruction of the condyle using posterior border of mandibular ramus in patients with temporomandibular joint ankylosis  

Microsoft Academic Search

The traditional approach for ankylosis is gap arthroplasty or interpositional arthroplasty followed by reconstruction of the condyle using, for example, costochondral grafts. As these are non-pedicled grafts, there is eventual resorption with subsequent decrease in height of the ramus, facial asymmetry and deviated mouth opening. The authors have applied the method of total and partial sliding vertical osteotomy on the

Y. Liu; A. Khadka; J. Li; J. Hu; S. Zhu; Y. Hsu; Q. Wang; D. Wang


Infection Following Total Knee Arthroplasty  

PubMed Central

For most orthopedists, total knee arthroplasty (TKA) has been regarded as the most effective surgery for patients with severe knee diseases. Though seldom occur, postoperative infection certainly remains one of the most devastating and dreaded complications of TKA. Thus, careful and early diagnosis is needed. After diagnosis, categorize the infection type and choose a rightful and sequential step of treatment are recommended.

Chun, Keun Churl; Kim, Kwang Mee



British contribution to knee arthroplasty.  


British surgeons and engineers contributed various types of knee prostheses, including hinged, unconstrained, and semiconstrained prostheses, in the development of total knee arthroplasty. Methods of implant fixation, the place of stems, pegs, the use of special instrumentation, and alignment procedures ensure both intrinsic and extrinsic prosthetic stability. PMID:3530580

Freeman, M A; Levack, B



Good function after shoulder arthroplasty  

PubMed Central

Background and purpose Different results after shoulder arthroplasty have been found for different diagnostic groups. We evaluated function, pain, and quality of life after shoulder arthroplasty in 4 diagnostic groups. Patients and methods Patients with shoulder arthroplasties registered in the Norwegian Arthroplasty Register from 1994 through 2008 were posted a questionnaire in 2010. 1,107 patients with rheumatoid arthritis (RA), osteoarthritis (OA), acute fracture (AF), or fracture sequela (FS) returned completed forms (65% response rate). The primary outcome measure was the Oxford shoulder score (OSS), which assesses symptoms and function experienced by the patient on a scale from 0 to 48. A secondary outcome measure was the EQ-5D, which assesses life quality. The patients completed a questionnaire concerning symptoms 1 month before surgery, and another concerning the month before they received the questionnaire. Results Patients with RA and OA had the best results with a mean improvement in OSS of 16 units, as opposed to 11 for FS patients. Both shoulder pain and function had improved substantially. The change in OSS for patients with AF was negative (–11), but similar end results were obtained for AF patients as for RA and OA patients. Quality of life had improved in patients with RA, OA, and FS. Interpretation Good results in terms of pain relief and improved level of function were obtained after shoulder arthroplasty for patients with RA, OA, and—to a lesser degree—FS. A shoulder arthropathy had a major effect on quality of life, and treatment with shoulder replacement substantially improved it.



Cup arthroplasty for rotator cuff tear arthropathy.  


Cup arthroplasty is a conservative bone-sparing option for resurfacing of the humeral head. Earlier reports have shown its effectiveness in appropriately selected patients with osteoarthritis, osteonecrosis, and severe rheumatoid arthritis. Patients with cuff tear arthropathy may also benefit from a modified cup arthroplasty technique. The purpose of this article is to describe the surgical technique involved in humeral cup arthroplasty in cuff tear arthropathy patients. We will review the indications, contraindications, complications, and postoperative rehabilitation. PMID:21358516

Mariscalco, Michael W; Patterson, Ryan W; Seitz, William H



Revision Arthroplasty in the Haemophiliac Patient  

PubMed Central

Arthroplasty in the haemophiliac patient is associated with higher rates of infection and is traditionally performed in a younger age group. Despite this there is little evidence in the literature regarding revision arthroplasty in this cohort of patients. We describe the case of a periprosthetic fracture in a haemophiliac patient requiring revision arthroplasty, who did not consent to receiving blood products due to religious beliefs, with a successful outcome.

Molloy, A. P.; O'Neill, B. J.; Molloy, L.; White, B.; Smyth, H.; Carthy, T. Mc.



Interposition mesocaval shunt for bleeding oesophageal varices in moderate and poor risk cirrhotics.  


A series of 45 mesocaval interposition shunt operations for bleeding oesophageal varices in Child's class B and C cirrhotics is presented. Twelve operations were carried out electively and 33 as emergencies. The primary mortality rates were 8% and 48% in these groups, respectively. Eleven (39%) of the 28 survivors died during a follow-up of 5 months to 4 years. Cumulative overall survival was 48% at one year and 33% at four years. Mortality was influenced more by surgery if performed as an emergency than the functional reserve of the liver. Continued alcoholism after surgery correlated with late mortality. Two cases of variceal rebleeding occurred in the primary survivor group (7%); both of them had shunt occlusion. Shunt patency rate was 89%. All patients had some degree of encephalopathy before surgery, but severe or chronic cases were not observed during the follow-up. Ascites when present preoperatively always disappeared after shunt. As a technically relatively simple procedure, mesocaval interposition shunt effectively prevents variceal rebleeding and ascites formation, thus offering improvement also in the quality of life. In elective cases an acceptably low mortality is achieved even in poor risk patients. In emergency cases mesocaval shunt provides about 50% chance of survival, if conservative methods to stop the bleeding fail. PMID:6976149

Järvinen, H; Kallio, H; Lempinen, M



Joint Gap Changes with Patellar Tendon Strain and Patellar Position During TKA  

PubMed Central

Balancing of the joint gap in extension and flexion is a prerequisite for success of a total knee arthroplasty. The joint gap is influenced by patellar position. We therefore hypothesized the state of the knee extensor mechanism (including the patellar tendon) would influence the joint gap. In 20 knees undergoing posterior-stabilized type total knee arthroplasties, we measured the joint gap and the patellar tendon strain from 0° to 135° flexion with the femoral component in position. When the patella was reduced, the joint gap was decreased at 90° and 135° (by 1.9 mm and 5.5 mm, respectively) compared with the gap with the patella everted. The patellar tendon strain increased with knee flexion. Patellar tendon strain at 90° flexion correlated with the joint gap difference with the patella in everted and reduced positions. This suggests that in addition to the collateral ligaments, the knee extensor mechanism may have an influence on the joint gap. Therefore, accounting for extensor mechanism tightness may be important in achieving the optimal joint gap balance during total knee arthroplasty. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Morita, Yuji; Matsushita, Isao; Sugimori, Kazuhito; Kimura, Tomoatsu



Thrombocytopenia after total knee arthroplasty.  


Heparin-induced thrombocytopenia is a serious complication during antithromboembolic prophylaxis caused by anti-heparin/platelet factor 4 (PF4) complex antibodies. It typically arises 3 to 15 days after the beginning of therapy and may result in an increased risk of arterial and venous thromboembolism. This article presents a case of thrombocytopenia associated with vein thrombosis in a man who underwent a total knee arthroplasty (TKA). PMID:19226055

Pesce, Vito; Patella, Vittorio; Scaraggi, Antonio; Petrera, Massimo; Sammarco, Giulio; Spinarelli, Antonio



Treatment of instability after total elbow arthroplasty.  


Instability after total elbow arthroplasty can be due to incorrect component selection or position, inadequacy of the medial or lateral ligaments or triceps tendon, polyethylene wear, limb malalignment, or trauma. Patients with significant loss of bone structure, ligament deficiency, and tendon deficiency around the elbow are at increased risk of instability following total elbow arthroplasty. PMID:11689380

O'Driscoll, S W; King, G J



Why do revision knee arthroplasties fail?  


This study identified the mechanisms of failure and the variables associated with failure after revision knee arthroplasty. Five hundred sixty-six index revision knee arthroplasties were studied. Of index revisions, 12.0% failed at an average of 40.1 months. Predominant revision failure modes included infection (46%), aseptic loosening (19%), and instability (13%). Only 4.3% of knees revised for aseptic loosening required rerevision as compared to 21% of knees revised for infection. Revision knee arthroplasty was more likely to fail in younger patients and in those who underwent polyethylene exchanges. Mechanisms of failure for revision arthroplasties are different than for primary knee arthroplasties. Revisions for infection are 4 times more likely to fail than revisions for aseptic loosening. The survivorship for the entire cohort, with revision for any reason as an end point, was 82% at 12 years. PMID:18538534

Suarez, Juan; Griffin, William; Springer, Bryan; Fehring, Thomas; Mason, J Bohannon; Odum, Susan



Small intestinal submucosa seeded with intestinal smooth muscle cells in a rodent jejunal interposition model  

PubMed Central

Background Small intestinal submucosa (SIS) is a porcine-derived, acellular, collagen-based matrix that has been tested without seeded smooth muscle cells (SMCs) for intestinal tissue engineering. We examined the expression patterns of contractile proteins of SIS with SMCs implanted in an in vivo rodent model. Materials and methods Intestinal SMCs were isolated from Lewis rat pups. Four-ply tubular SMCs-seeded SIS or blank SIS scaffolds were implanted in an adult rat jejunal interposition model. Recipients were sacrificed at 2, 4, and 8 weeks following the implantation. The retrieved specimens were examined using antibodies against contractile proteins of SMCs. Results Cultured intestinal SMCs expressed ?-smooth muscle actin (?-SMA), calponin, and less smooth muscle myosin heavy chain (SM-MHC) in vitro. Cell-seeded SIS scaffolds contracted significantly over 8 weeks of implantation but were comparable to SIS scaffolds without cell seeding. Implanted cell-seeded SIS scaffolds at 2 weeks expressed extensive ?-SMA, some calponin, and minimal SM-MHC. At 4 weeks, ?-SMA-expressing cells decreased significantly, whereas calponin or SM-MHC expressing cells were rarely detected. A small number of ?-SMA-expressing cells were present at 8 weeks, whereas more calponin or SM-MHC expressing cells emerged in proximity with the anastomotic interface. Conclusions Cell-seeded SIS contracted significantly after implantation, but the expressions of contractile proteins were present at the site of SIS interposition. No organized smooth muscle was formed at the site of implantation. A better scaffold design is needed to produce structured smooth muscle.

Qin, Harry H.; Dunn, James C.Y.



Thumb carpometacarpal arthroplasty using an absorbable interference screw for flexor carpi radialis ligament reconstruction.  


Few surgical techniques that address advanced thumb carpometacarpal osteoarthrosis specifically allow early mobilization postoperatively. After trapeziectomy, we carry out a ligament reconstruction using an absorbable interference screw to secure a flexor carpi radialis tendon autograft within the first metacarpal base. Theoretically, superior tendon graft fixation strength allows early mobilization within 2 weeks postoperatively. We have retrospectively compared our clinical results using this technique with another group of patients who underwent traditional ligament reconstruction and tendon interposition as described by Burton and Pellegrini. There were no differences in the verbal pain score, satisfaction rating, or DASH scores between groups. There was a statistically significant decrease in trapezial space ratio both at rest and with stress for the experimental group. Although the clinical significance of this finding is largely unknown, it did not correlate with clinical outcome in our patients. Although no conclusions could be drawn regarding early mobilization after thumb carpometacarpal arthroplasty, further studies are planned to investigate this intriguing aspect of postoperative care. In this article, we present the details of the surgical technique and postoperative rehabilitation. PMID:21606785

Brunton, Lance M; Wittstadt, Raymond A



Contoured iliac crest allograft interposition for pericapsular acetabuloplasty in developmental dislocation of the hip: technique and short-term results  

PubMed Central

Background Pericapsular acetabuloplasty procedures have been widely used as an integral component of combined surgery to treat developmental hip dislocation after walking age. The stability of the acetabuloplasty and the maintenance of the acetabular correction will depend on the structural integrity of the iliac crest autograft, which, traditionally, has been inserted as the interposition material. Problems related to the use of an autograft have been encountered by various surgeons—including the authors—namely, graft displacement and resorption, which may necessitate internal fixation or result in revision surgery. To overcome autograft failure, the use of an allograft as the interposition material has been introduced by some surgeons. This study describes the radiologic results of 147 hips treated for developmental hip dislocation by means of a standard protocol of open hip reduction and pericapsular acetabuloplasty with a contoured iliac crest allograft as the interposition material. Methods This retrospective study reviewed the radiographs of 147 hips presenting with late developmental dislocation which were treated by open reduction and a concomitant pericapsular acetabuloplasty using a contoured iliac crest allograft as the interposition material. The minimum follow up period was 2 years. Measurement of the acetabular index (AI) was the main variable. The efficacy of the interposed iliac crest allograft as the main stabiliser of the acetabuloplasty was reflected by the maintenance of the corrected AI during the follow up period. Loss of acetabular correction, graft extrusion or resorption, the need for osteotomy internal fixation, delayed or non union, infection, hip redislocation and avascular necrosis (AVN) as possible complications were documented. Results The treatment protocol of a combined open reduction of the hip and pericapsular acetabuloplasty, inserting a contoured iliac crest allograft as the interposition material, resulted in concentrically reduced and stable hips in 96.6% of our cases. The redislocation rate was 3.4%. All of the allografts were completely incorporated at 6 months post-surgery with no graft-related infections. In only two hips was the acetabular correction not maintained. None of the osteotomies required internal fixation for stability, even in older children. Conclusion We believe that a contoured iliac crest allograft as the pericapsular acetabuloplasty interposition material renders excellent osteotomy stability that eliminates the need for internal fixation and—in the short-term—maintains the correction of the acetabulum achieved intra-operatively.

Alhussainan, Thamer S.; Al Zayed, Zayed; Hamdi, Nezar; Bubshait, Dalal



Infection after primary hip arthroplasty  

PubMed Central

Background and purpose The aim of the present study was to assess incidence of and risk factors for infection after hip arthroplasty in data from 3 national health registries. We investigated differences in risk patterns between surgical site infection (SSI) and revision due to infection after primary total hip arthroplasty (THA) and hemiarthroplasty (HA). Materials and methods This observational study was based on prospective data from 2005–2009 on primary THAs and HAs from the Norwegian Arthroplasty Register (NAR), the Norwegian Hip Fracture Register (NHFR), and the Norwegian Surveillance System for Healthcare–Associated Infections (NOIS). The Norwegian Patient Register (NPR) was used for evaluation of case reporting. Cox regression analyses were performed with revision due to infection as endpoint for data from the NAR and the NHFR, and with SSI as the endpoint for data from the NOIS. Results The 1–year incidence of SSI in the NOIS was 3.0% after THA (167/5,540) and 7.3% after HA (103/1,416). The 1–year incidence of revision due to infection was 0.7% for THAs in the NAR (182/24,512) and 1.5% for HAs in the NHFR (128/8,262). Risk factors for SSI after THA were advanced age, ASA class higher than 2, and short duration of surgery. For THA, the risk factors for revision due to infection were male sex, advanced age, ASA class higher than 1, emergency surgery, uncemented fixation, and a National Nosocomial Infection Surveillance (NNIS) risk index of 2 or more. For HAs inserted after fracture, age less than 60 and short duration of surgery were risk factors of revision due to infection. Interpretation The incidences of SSI and revision due to infection after primary hip replacements in Norway are similar to those in other countries. There may be differences in risk pattern between SSI and revision due to infection after arthroplasty. The risk patterns for revision due to infection appear to be different for HA and THA.



Use of the descending branch of the lateral femoral circumflex vessels as a composite interposition graft in lower extremity reconstruction.  


The prevailing treatment for distal third lower extremity defects is with autologous free tissue transfers. In the trauma patient, these reconstructions are wrought with challenges, including the selection of appropriate recipient vessels, avoiding the zone of injury, and choosing the appropriate flap for transfer, all while maintaining perfusion to the foot. With distal defects and a large zone of injury, the free flap pedicle may need additional length to cover the defect and reach the recipient vessels without excess tension. The creation of an arteriovenous loop from an autologous vein graft is the usual solution. We present a case where additional pedicle length was needed to have a free flap completely cover a distal leg defect and connect to the anterior tibial vessels proximally. The saphenous vein was not available as an interposition graft; therefore, the descending branch of the lateral femoral circumflex artery and venae comitantes were used as a composite arteriovenous interposition graft. PMID:21400580

Echo, Anthony; Bullocks, Jamal M



Outcome analysis of trapezectomy with and without pyrocarbon interposition to treat primary arthrosis of the trapeziometacarpal joint.  


We performed a prospective cohort comparative analysis of simple trapezectomy and trapezectomy with pyrocarbon interposition in 38 consecutive patients with trapeziometacarpal joint osteoarthrosis. Patients were assessed preoperatively, at six and 12 months postoperatively using subjective and objective tools. Subjective assessment was performed using the Quick Disabilities of the Arm, Shoulder, and Hand questionnaire and the visual analogue score. Objective assessment was performed with grip strength measurements. At each time interval, statistical differences were sought between the two subgroups. No significant difference between the two subgroups was noted at any time interval on subjective or objective assessment. A significant difference (p < 0.05) was found on comparing the respective preoperative and 12-month subjective scores in both subgroups. Of the pyrocarbon subgroup seven had related complications. We suggest that pyrocarbon interposition does not significantly improve postoperative function, requires a longer operation with a high postoperative risk of pyrocarbon displacement and need for revision surgery. PMID:21348031

Colegate-Stone, T J; Garg, S; Subramanian, A; Mani, G V



Shoulder and elbow function 2 years following long head triceps interposition flap transfer for massive rotator cuff tear reconstruction  

Microsoft Academic Search

Introduction  Patient outcomes were determined at a minimum of 2 years following massive rotator cuff tear ( ? 5 cm2) reconstruction using a triceps brachii long head interposition flap. A physiotherapist at an independent clinic performed all measurements.Patients and methods  Of 24 total eligible patients, 19 completed pre-operative and follow-up UCLA Shoulder Scores and ASES Function Scores. Of these 19 patients, 14 who did not have

J. Keen; J. Nyland; Y. Kocabey; A. Malkani



Investigation of the portal perfusion index after low diameter mesocaval interposition and distal splenorenal shunt — a prospective study  

Microsoft Academic Search

Summary  In 50 consecutive patients portal blood flow was determined using computed liver perfusion scintigraphy preoperatively and\\u000a at 6, 12, 24, 36, 48, 60, 72, and 84 months postoperatively between 1 January 1983 and 1 January 1990. All 25 subjects had\\u000a undergone placement of a distal splenorenal shunt (DSRS) and 25, insertion of low-diameter PTFE mesocaval interposition shunt\\u000a (LDMIS) between 15

K.-J. Paquet; M. A. Mercado; H. Klingele; R. Klingele



The horizon line, linear perspective, interposition, and background brightness as determinants of the magnitude of the pictorial moon illusion  

Microsoft Academic Search

A total of 110 undergraduate students participated in a series of three experiments that explored the magnitude of the moon\\u000a illusion in pictures. Experiment 1 examined the role of the number and salience of depth cues and background brightness. Experiment\\u000a 2 examined the role of the horizon line, linear perspective, interposition, and background brightness. In Experiment 3, comparative\\u000a distance judgments

Stephanie A. H. Jones; Alexander E. Wilson



Femur positioning in navigated total knee arthroplasty.  


Navigated total knee arthroplasty (TKA) results in better restoration of neutral mechanical axis than does the conventional technique. Nevertheless, coronal malalignment has not been eliminated. It is yet unknown whether errors in implant positioning occur more on the femoral side, more on the tibial side, or equally on both sides. The hypothesis of this study was that a predominance of coronal component malalignment exists on the tibial side in navigated tibia-first TKA.Fifty-seven consecutive navigated (OrthoPilot; B. Braun Aesculap, Tuttlingen, Germany) TKAs were included in this retrospective study. Pre- and postoperative digital whole-leg standing radiographs were analyzed. Coronal alignment was measured for the whole leg pre- and postoperatively. Lateral distal femur angle and medial proximal tibia angle were analyzed on the preoperative radiographs. On the postoperative radiographs, coronal alignment of the femoral and tibial components were measured separately in reference to the tibial and femoral mechanical axis. The coronal alignment improved from 8.2° ± 3.7° preoperatively to 1.1° ± 1.2° postoperatively, with 5 (8%) outliers outside the 3° window. The femoral component was malaligned (0.6° ± 0.6°), whereas the tibial component showed a significantly higher deviation from the mechanical axis of 1.0° ± 1.1° (P=.009). The femoral component was positioned more precisely than the tibial component. The latter influences gap management in the tibia-first technique and may thereby have a relevant effect on joint stability. Accuracy of the surgical technique and differences in the mathematical algorithm for the determination of landmarks are possible reasons for the difference in precision between the femoral and tibial component positioning. PMID:23026252

Pfitzner, Tilman; Röhner, Eric; Preininger, Bernd; Perka, Carsten; Matziolis, Georg



New Technologies in Knee Arthroplasty.  


Advances in surgical technique and implant design have increased the treatment options available to joint reconstruction surgeons. New technologies for component alignment such as custom cutting blocks and disposable cutting blocks hold the potential for more anatomic component positioning and less instrument turnover which may decrease infection rates. Improved component alignment may also be obtained with the use of computer-assisted surgery. Utilization of bone-sparing designs such as patellofemoral, unicompartmental, and bicompartmental knee arthroplasty allow for the surgeon to customize treatment based on patient symptoms by addressing each compartment individually. Gender-specific designs may be useful in the setting of populations which deviate from standard dimensions that are available in traditional unisex designs. New higher-conforming bearing designs such as rotating platform bearings allow for more natural knee kinematics, while also limiting polyethylene wear by decreasing contact stress.Newer interfaces for cementless fixation utilizing porous coated surfaces allows for biologic component fixation which has the potential to increase interface durability and implant survivorship. These new materials, designs, and techniques are challenging the traditional "gold standard" cemented total knee arthroplasty and have the potential for developing a more durable and naturally feeling prosthetic knee. Further study is required to identify which patients are most appropriate for each new technology. PMID:22915499

Naziri, Qais; Pivec, Robert; Johnson, Aaron J; Harwin, Steven F; Bonutti, Peter M; Costa, Christopher R; Mont, Michael A



Reverse shoulder arthroplasty - a literature review.  


Professor Grammont revolutionised shoulder surgery with his reverse shoulder arthroplasty design. Patients who had poor results from a conventional shoulder replacement because of cuff deficiency can now be treated effectively. Although designed for cuff tear arthropathy, indications continue to evolve and broaden. The initial results look very promising and the implant has gained much popularity over the years. The article provides an extensive literature review of the indications, results and complications for reverse shoulder arthroplasty. PMID:24082977

Mahmood, Aatif; Malal, Joby Jacob George; Waseem, Mohammed



Reverse Shoulder Arthroplasty - A Literature Review  

PubMed Central

Professor Grammont revolutionised shoulder surgery with his reverse shoulder arthroplasty design. Patients who had poor results from a conventional shoulder replacement because of cuff deficiency can now be treated effectively. Although designed for cuff tear arthropathy, indications continue to evolve and broaden. The initial results look very promising and the implant has gained much popularity over the years. The article provides an extensive literature review of the indications, results and complications for reverse shoulder arthroplasty.

Mahmood, Aatif; Malal, Joby Jacob George; Waseem, Mohammed



Glenoid Reconstruction in Revision Shoulder Arthroplasty  

Microsoft Academic Search

Failed shoulder arthroplasty associated with glenoid bony deficiency is a difficult problem. Revision surgery is complex with\\u000a unpredictable outcome. We asked whether revision shoulder arthroplasty with glenoid bone grafting could lead to good outcome.\\u000a We retrospectively reviewed 21 patients who underwent glenoid bone grafting using corticocancellous bone grafting or impaction\\u000a grafting using cancellous bone graft. Three patients underwent revision TSA,

Bassem Elhassan; Mehmet Ozbaydar; Lawrence D. Higgins; Jon J. P. Warner



Venous thromboembolic disease management patterns in total hip arthroplasty and total knee arthroplasty patients  

Microsoft Academic Search

The American Association of Hip and Knee Surgeons (AAHKS) distributed a survey to its members exploring practice patterns implemented to prevent venous thromboembolic disease (VTED) in patients undergoing total hip arthroplasty (THA) and total knee arthroplasty (TKA). Of 720 (33%) members, 236 responded. Prophylaxis was prescribed for 100% of patients during the course of hospitalization for THA and TKA. Warfarin

J. Wesley Mesko; Richard A Brand; Richard Iorio; Ivan Gradisar; Richard Heekin; Ross Leighton; Robert Thornberry



In vivo kinematic analysis of squatting after total hip arthroplasty  

Microsoft Academic Search

BackgroundThe in vivo kinematics of squatting after total hip arthroplasty is unclear. The purpose of the present study was to determine the range of motion of the hip joint during squatting after total hip arthroplasty.

Junichiro Koyanagi; Takashi Sakai; Takaharu Yamazaki; Tetsu Watanabe; Keisuke Akiyama; Nobuhiko Sugano; Hideki Yoshikawa; Kazuomi Sugamoto



Meniscal repair enhanced by an interpositional free synovial autograft: an experimental study in rabbits.  


This report describes the methods and effectiveness of interpositional free synovial autografts (IPFSAs) in promoting the healing of lesions in the avascular portion of the knee joint meniscus in rabbits. Thirty-four specimens were divided into two groups: 17 in the study group and 17 in the control group. The medial meniscus of the left knee joint was excised in each rabbit, and an artificial longitudinal tear was created in the avascular zone of the meniscus. In the study group, an IPFSA was sewn into the tear with a single horizontal suture. In the control group, the tear was repaired without synovium in the same manner. The menisci were then implanted into the right knee joint in the respective animals. At intervals the animals were killed, and the menisci were examined grossly and microscopically. Three menisci were eliminated because they had become attached to the synovial wall. In the study group, the lesion completely healed by 4 weeks, except for one. The menisci in the control group never completely healed, particularly at the deeper levels of the lesion. At 8-16 weeks, autolysis of the specimens made microscopic examination difficult and unreliable in both groups. Based on these results, it has been concluded that an IPFSA can promote the healing process in the avascular zone of a torn meniscus in rabbits and that systemic vascularity to the synovium or the meniscus is not essential for healing to occur. PMID:7880359

Jitsuiki, J; Ochi, M; Ikuta, Y



Internal Fixation After Subtrochanteric Femoral Fracture After Hip Resurfacing Arthroplasty  

Microsoft Academic Search

Periprosthetic fractures around total hip arthroplasty create surgical challenges with many described techniques of either fixation or revision. The increasing popularity of hip resurfacing arthroplasty poses different problems especially if there is a desire to retain the prosthesis rather than converting to a total hip arthroplasty. We describe a previously unreported technique of fixation for a comminuted, proximal femoral fracture,

Paul Whittingham-Jones; Godfrey Charnley; Jason Francis; Satyanarayana Annapureddy



Medial patellofemoral ligament reconstruction for subluxating patellofemoral arthroplasty.  


Patellofemoral joint (PFJ) arthroplasty has become a successful operation for patellofemoral osteoarthritis. The post-operative complication of patella subluxation is uncommon. We report the stabilisation of a subluxating patella following PFJ arthroplasty using autogenous hamstring tendons. Medial patellofemoral ligament reconstruction may be considered a method of stabilising a subluxating patellofemoral replacement in patients for whom revision arthroplasty is not recommended. PMID:20619661

Carmont, M R; Crane, T; Thompson, P; Spalding, T



Total elbow arthroplasty: current options.  


Total elbow arthroplasty (TEA) has changed considerably in the past three decades. Based on the good long-term results with TEA in patients with rheumatoid arthritis, the indications expanded to include management of acute traumatic and posttraumatic conditions in young, higher-demand patients. Today, unlinked, linked semiconstrained, and convertible devices are available. The high complication rate with earlier surgeries led to surgical advances such as new cementing technique and a focus on managing the triceps. Complications such as infection, aseptic loosening, polyethylene wear, periprosthetic fracture, triceps insufficiency, wound breakdown, and ulnar nerve injury will continue to spur the evolution of surgical technique and implant design. Refinement of surgical indications and improvement in implant fixation, polyethylene design, component implantation, and pathology-specific implants will determine the future success of TEA. PMID:23818030

Choo, Andrew; Ramsey, Matthew L



[Update on total hip arthroplasty].  


Total hip arthroplasty (THA) is one of the most common surgical procedures performed by orthopedic surgeons. Frequent indications for THA include osteoarthrosis of the hip joint that can be primary origin or secondary to dysplasia or traumatic origin, as well as fractures of the femoral neck in active patients. Other common indications include rheumatoid arthritis and osteonecrosis of the femoral head. It is a surgical intervention giving very good results giving patients pain relief and mobility with a success rate in more than 90% of cases. The point of this article is to inform the medical community on the actual situation of hip prosthetics in fields including epidemiology, clinical results, indications, contraindications, different types of prosthetic materials as well as surgical approaches. PMID:21250424

Christofilopoulos, Panayiotis; Lübbeke, Anne; Peter, Robin; Hoffmeyer, Pierre



Primary resection of the posterior cruciate ligament does not produce a gap mismatch in the navigated gap technique.  


Treatment of the posterior cruciate ligament (PCL) is a matter of continued controversy in total knee arthroplasty. By using so-called cruciate ligament-substituting implant designs, retention and resection of the PCL produce equivalent clinical results. However, it remains unclear whether primary resection of the PCL leads to relevant instabilities of the flexion gap. Especially when the increasingly popular navigated gap technique is used, this would result in a nonanatomic size selection and positioning of the femoral component and thus compromise the clinical outcome. The objective of this retrospective study was therefore to determine whether the navigated gap technique leads to a mismatch of the flexion and extension gap in primary routine resection of the PCL. In 92 patients consecutively enrolled in this study (92 knees), the flexion and extension gap were determined and documented after tibial resection, using the navigated gap technique navigation system (OrthoPilot 4.0; B. Braun Aesculap, Tuttlingen, Germany). The flexion gap was 10.4 ± 2.6 (2.5-19.5) mm; the extension gap was 10.4 ± 2.4 (5.5-17.5) mm. The individual difference was normally distributed around 0.0 ± 2.9 (-7 to 7) mm. In the navigated gap technique, primary routine resection of the PCL does not lead to a mismatch of the flexion and extension gap, so that a systematic nonanatomic resection of the femur can be ruled out. PMID:20954634

Matziolis, Georg; Perka, Carsten



Femoral cement grading in total hip arthroplasty.  


The current gold standard for primary total hip arthroplasty is a cemented femoral component combined with a porous-coated acetabular component. Barrack and colleagues described a femoral cement mantle grading system which is increasingly being used to evaluate surgical technique and to compare arthroplasty results. The immediate postoperative radiographs of 100 primary total hip arthroplasty cases from five community surgeons were assessed by three observers to evaluate the overall quality of cement technique, the interobserver variability in cement mantle grading, and specific characteristics of the grading system. All three observers agreed on the grading in only 73% of the x-rays (anteroposterior view, 69%; lateral view, 77%). Compared with reports in the literature from specialized hip arthroplasty centers, a very high proportion of the cases had grade C mantles. To gain a balanced perspective of the global effectiveness and longevity of cemented total hip arthroplasty it is important that follow-up studies be reported upon from representative cross sections of the orthopaedic community. PMID:9645519

Harvey, E J; Tanzer, M; Bobyn, J D



Short-Term and MidTerm Control of Type 2 Diabetes Mellitus by Laparoscopic Sleeve Gastrectomy with Ileal Interposition  

Microsoft Academic Search

Background  Standard surgical procedures used for the treatment of morbid obesity constitute optional treatments for type 2 diabetes mellitus\\u000a (T2DM). The aim of the present study was to evaluate the short- and mid-term effects of laparoscopic sleeve gastrectomy (SG)\\u000a with ileal interposition (II) in T2DM patients (n = 30).\\u000a \\u000a \\u000a \\u000a \\u000a Methods  The variables investigated were the feasibility of the procedure, remission\\/alleviation of the disease, morbidity,

Augusto Tinoco; Luciana El-Kadre; Livia Aquiar; Renam Tinoco; Paulo Savassi-Rocha


The dimensional accuracy of preparation of femoral cavity in cementless total hip arthroplasty*  

PubMed Central

Objective: To observe the accuracy of femoral preparation and the position of the cementless prosthesis in femoral cavity, and to compare the results between the computer-assisted surgical group (CASPAR) and the conventional group. Methods: Ten femoral components were implanted either manually or by CASPAR in cadaver femurs. The specimens were cut to 3 mm thick slices. Microradiograms of every slice were sent to a computer for analysis with special software (IDL). The gaps and the medullary cavities between component and bone, the direct bone contact area of the implant surface, the gap width and the percentage of gap and bone contact area were measured in every slice. Results: In the proximal implant coated with HA of the CASPAR group, the average percentage of bone contact reached 93.2% (ranging from 87.6% to 99.7%); the average gap percentage was 2.9% (ranging from 0.3% to 7.8%); the maximum gap width was 0.81 mm and the average gap width was only 0.20 mm. While in the conventional group, the average percentage of bone contact reached 60.1% (ranging from 49.2% to 70.4%); the average gap percentage was 32.8% (ranging from 25.1% to 39.9%); the maximum gap width was 2.97 mm and the average gap width was 0.77 mm. The average gap around the implant in the CASPAR group was only 9% of that in the manual group; the maximum and average gap widths were only about 26% of those in the manual group. On the other hand, the CASPAR group showed 33% higher bone contact than the manual group. Conclusion: With the use of robotics-assisted system, significant progress can be achieved for femoral preparation in total hip arthroplasty.

Wu, Li-dong; Hahne, HJ; Hassenpflug, J



Semimembranosus release as the second step of soft tissue balancing in varus total knee arthroplasty.  


There have been limited clinical data on the effect of semimembranosus release in patients with varus knees treated with total knee arthroplasty (TKA). The purposes of this study were to determine the effect of semimembranosus release and to evaluate the effectiveness of our release technique based on the three-step algorithm which consisted of sequential release of 1) deep medial collateral ligament (MCL), 2) semimembranosus, 3) superficial MCL in 104 consecutive varus knees treated with TKA. Semimembranosus release had the desired effect on gap balancing in varus knees and our algorithmic medial release approach to the varus knee has shown to be favorable in correcting varus deformities during TKA. PMID:23159061

Koh, Hae Seok; In, Yong



Past, present, and future of cervical arthroplasty.  


Cervical arthroplasty was developed in an attempt to maintain cervical motion and potentially to avoid or minimize adjacent-segment degeneration. If cervical arthroplasty is successful, the long-term results of surgery for cervical disc disease should improve. However, problems associated with cervical arthroplasty have been reported: these include kyphosis, heterotopic ossification-induced motion limitation, no motion preservation even at the index level, and a higher revision rate in a limited number of cases compared with anterior cervical discectomy and fusion (ACDF). In addition, for degenerative cervical disc disorders, the risk of developing adjacent segment degeneration more than 2 years after surgery is reportedly similar for ACDF and cervical arthroplasty. Cervical disc arthroplasty is an emerging motion-sparing technology and is currently undergoing evaluation in many countries as an alternative to arthrodesis for the treatment of cervical radiculopathy and myelopathy. The decision whether to use arthrodesis or arthroplasty is a difficult one. The achievement of good prosthetic performance demands exacting implantation techniques to ensure correct placement. This fact underlines the increasing importance of special instrumentation and surgical skills that involve an understanding of prosthetic lubrication, wear, and biologic effects and familiarity with currently available information regarding kinematics, basic science, testing, and early clinical results. Fortunately, a number of devices are at the late preclinical study stage or at the early clinical trial stage, and results in many cases are promising. In the near future, it is likely that new designs will be produced to replace spinal discs totally or partially in a pathologic entity-specific manner. PMID:23803346

Hyun Oh, Chang; Hwan Yoon, Seung



Shoulder arthroplasty for the young, active patient.  


Patients younger than 55 years with degenerative conditions of the glenohumeral joint represent a unique population that can be treated with shoulder arthroplasty. Certain challenges related to this cohort may include greater patient expectations, higher functional demands, soft-tissue contracture from previous surgery, and glenoid bone loss. Surgical treatment options include unconstrained total shoulder arthroplasty; hemiarthroplasty; humeral head resurfacing alone; hemiarthroplasty with concentric reaming of the glenoid; and hemiarthroplasty with adjunctive biologic glenoid resurfacing with autogenous fascia lata, Achilles tendon allograft, or meniscal allograft. PMID:21553765

Tibbetts, Ryan M; Wirth, Michael A



The clinical outcome of patellofemoral arthroplasty.  


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



Results and outcomes of unicompartmental knee arthroplasty.  


Precise outcome evaluation is mandatory to improve analysis of the results of knee replacement procedures. Patients' expectations toward surgery and activity levels have increased with changes in patient populations and improvement of surgical results. It is difficult, however, to accurately assess outcomes because objective evaluation of patient function performed only by a surgeon remains highly inaccurate. New methods of objective evaluation after unicompartmental knee arthroplasty have been developed. These devices provide information about range of motion and patient function during daily activities. This article provides up-to-date information concerning the different tools of function evaluation after unicompartmental knee arthroplasty. PMID:23827833

Ollivier, Matthieu; Parratte, Sebastien; Argenson, Jean-noël



Total Knee Arthroplasty Considerations in Rheumatoid Arthritis  

PubMed Central

The definitive treatment for advanced joint destruction in the late stages of rheumatoid arthritis can be successfully treated with total joint arthroplasty. Total knee arthroplasty has been shown to be a well-proven modality that can provide pain relief and restoration of mobility for those with debilitating knee arthritis. It is important for rheumatologists and orthopedic surgeons alike to share an understanding of the special considerations that must be addressed in this unique population of patients to ensure success in the immediate perioperative and postoperative periods including specific modalities to maximize success.

Danoff, Jonathan R.; Geller, Jeffrey A.



Cost-effectiveness of total hip arthroplasty versus resurfacing arthroplasty: economic evaluation alongside a clinical trial  

PubMed Central

Objective To report on the relative cost-effectiveness of total hip arthroplasty and resurfacing arthroplasty (replacement of articular surface of femoral head only) in patients with severe arthritis suitable for hip joint resurfacing arthroplasty. Design Cost-effectiveness analysis on an intention-to-treat basis of a single-centre, single-blind randomised controlled trial of 126 adult patients within 12?months of treatment. Missing data were imputed using multiple imputations with differences in baseline quality of life and gender adjusted using regression techniques. Setting A large teaching hospital trust in the UK. Participants A total of 126 adult patients with severe arthritis of the hip joint suitable for a resurfacing arthroplasty of the hip. Results Data were received for 126 patients, 4 of whom did not provide any resource use data. For the remainder, data were imputed for costs or quality of life in at least one time point (baseline, 3, 6?months and 1?year) for 18 patients. Patients in the resurfacing arm had higher quality of life at 12?months (0.795 vs 0.727) and received 0.032 more QALYs within the first 12?months postoperation. At an additional cost of £564, resurfacing arthroplasty offers benefits at £17?451 per QALY within the first 12?months of treatment. When covariates are considered, the health economic case is stronger in men than in women. Conclusions Resurfacing arthroplasty appears to offer very short-term efficiency benefits over total hip arthroplasty within a selected patient group. The short-term follow-up in this trial should be noted, particularly in light of the concerns raised regarding adverse reactions to metal debris from metal-on-metal bearing surfaces in the longer term. Longer-term follow-up of resurfacing arthroplasty patients and decision analytic modelling is also advised. Trial registration Current controlled Trials ISRCTN33354155. UKCRN 4093.

Edlin, Richard; Tubeuf, Sandy; Achten, Juul; Parsons, Nicholas; Costa, Matthew



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.

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



Multiple prosthetic infections after total joint arthroplasty  

Microsoft Academic Search

The relative risk of age, sex, underlying diagnosis, corticosteroid usage, diabetes mellitus, and major nonprosthetic infection for the development of multiple prosthetic infections was assessed retrospectively. Deep infection occurred in 174 replacement arthroplasties in 145 patients between 1981 and 1993. Patients with rheumatoid arthritis had a significantly larger number of implants per patient (P < .001). Twenty-seven of 145 patients

Christian P. Luessenhop; Laurence D. Higgins; Barry D. Brause; Chitranjan S. Ranawat



Arthroplastie de la hanche par cupules couplées  

Microsoft Academic Search

Hip arthroplasty with matched cups has been in use since March 1970. A femoral cup with cylindrical supporting wall fits inside a second hemispherical cup which is loose within the deepened acetabulum. In this way a total hip system is produced with self adjustment of the acetabular cup during movement.

Y. Gérard; Ph. Segal; J. S. Bedoucha



Anterior iliopsoas impingement after total hip arthroplasty  

Microsoft Academic Search

Pain after total hip arthroplasty (THA) can be caused by a multitude of conditions, including infection, aseptic loosening, heterotopic ossification, and referred pain. It is also recognized that soft tissue inflammation about the hip, such as trochanteric bursitis, can lead to hip pain after THA. Two cases of persistent iliopsoas tendinitis following THA are reported, which are believed to be

Robert T. Trousdale; Miguel E. Cabanela; Daniel J. Berry



Perichondrial wrist arthroplasty in rheumatoid patients.  


A new method is proposed for reconstruction of the wrist joint in rheumatoid arthritis. Perichondrial arthroplasty done in four patients with severe deformity of the wrist from rheumatoid arthritis gave functionally improved results. In one case biopsy of the reconstructed joint showed newly formed cartilaginous tissue four months after initial surgery. PMID:488794

Pastacaldi, P; Engkvist, O



Magnetic resonance imaging of painful shoulder arthroplasty  

Microsoft Academic Search

Specialized magnetic resonance imaging (MRI) was performed in 42 painful shoulder arthroplasties, 22 of which underwent subsequent revision surgery, allowing surgical confirmation of the pathology identified on MRI. One hemiarthroplasty was excluded because of motion artifact, leaving 21 studies (19 patients) to be correlated retrospectively to the surgical findings. At the time of revision surgery, there were full-thickness rotator cuff

John W Sperling; Hollis G Potter; Edward V Craig; Evan Flatow; Russell F Warren



Prodromes of failure in total knee arthroplasty  

Microsoft Academic Search

A total of 102 revision total knee arthroplasties (TKAs) were reviewed to determine the prodromal symptoms and radiographic findings associated with failure. Presenting symptoms included pain (84%); swelling (76%); progressive varus or valgus deformity (19%); instability (17%); stiffness (17%); clicking or grinding (7%); catching (4%); and patellar pain, subluxation, or clicking (4%). Radiographs were diagnostic in 91% of cases, demonstrating

Jess H. Lonner; John M. Siliski; Richard D. Scott



Complex primary total hip arthroplasty.  


Although total hip arthroplasty is now a classic procedure that is well controlled by orthopedic surgeons, some cases remain complex. Difficulties may be due to co-morbidities: obesity, skin problems, muscular problems, a history of neurological disease or associated morphological bone deformities. Obese patients must be informed of their specific risks and a surgical approach must be used that obtains maximum exposure. Healing of incisions is not a particular problem, but adhesions must be assessed. Neurological diseases may require tenotomy and the use of implants that limit instability. Specific techniques or implants are necessary to respect hip biomechanics (offset, neck-shaft angle) in case of a large lever arm or coxa vara. In case of arthrodesis, before THA can be performed, the risk of infection must be specifically evaluated if the etiology is infection, and the strength of the gluteal muscles must be determined. Congenital hip dysplasia presents three problems: the position and coverage of the cup, placement of a specific or custom made femoral stem, with an osteotomy if necessary, and finally lowering the femoral head into the cup by freeing the soft tissues or a shortening osteotomy. Acetabular dysplasia should not be underestimated in the presence of significant bone defect (BD), and reconstruction with a bone graft can be proposed. Sequelae from acetabular fractures presents a problem of associated BD. Internal fixation hardware is rarely an obstacle but the surgical approach should take this into account. Treatment of acetabular protrusio should restore a normal center of rotation, and prevent recurrent progressive protrusion. The use of bone grafts and reinforcement rings are indispensible. Femoral deformities may be congenital or secondary to trauma or osteotomy. They must be evaluated to restore hip biomechanics that are as close to normal as possible. Fixation of implants should restore anteversion, length and the lever arm. Most problems that can make THA a difficult procedure may be anticipated with proper understanding of the case and thorough preoperative planning. PMID:23375960

Boisgard, S; Descamps, S; Bouillet, B



Slovakian Arthroplasty Register. Review of the annual report of the Slovakian Arthroplasty Register - 2010.  


This annual report of Slovakian Arthroplasty Register (SAR) is an official document dealing with all arthroplasty procedures performed in Slovakia from January 1st until December 30th, 2010. During that period the population of Slovakia reached 5,435,273. During the observed period 4,970 primary arthroplasties and 457 revision arthroplasties were performed. In general, the number of arthroplasty procedures depends on the demographic growth of the population. This annual report is divided into two main parts - arthroplasty of the hip joint and the arthroplasty of the knee joint: it contains summary statistics from all surgical departments performing arthroplasty procedures. In the hip joint section, it evaluates data from 40 orthopaedic and traumatology departments in 2010, the incidence of primary total hip arthroplasty (THA) was 91.42 per 100,000 inhabitants. From the year 2003, when the incidence was 39.39 per 100,000 inhabitants, the percentage growth has been 232%. In 2010, the revision rate reached 9.20%, representing annual increase of 1.1%. The revision rate in whole observed period 2003-2010 reached 9.15%.The mean age of all patients undergoing primary THA was 64.66 years. Sixty percent were female and 40% male. Primary coxarthrosis was the main indication for the surgery in 57.75%. Compared to 2003, when it was 54.33% the increase was minimal. In 2003, dysplasia was as the main indication in 10.01% and in 2010 this figure reached 11.39%. In 19.68% the indication was femoral neck fracture. Regarding the type of the arthroplasty, total hip arthroplasty was used in 86.78% of all cases, unipolar hemiarthroplasty was used in 12.45% cases and bipolar hemiarthroplasty accounted for only 0.76% of all cases. Cement was used for all components in 35.45% of all arthoplasties, 53.25% were uncemented and 11.28% were hybrids. We have observed significant growth in the uncemented type of fixation. In 2003, the uncemented type of fixation was used in only 23.07% of all cases. The SAR started with data collection in total knee arthroplasty (TKA) on January 1st, 2006. In 2010, TKA was practised in 28 surgical departments, in which 2,198 primary and 97 revision arthroplasties were performed. Females comprised 67.38% and males 32.62%. The incidence of TKA was 40.44 per 100,000 of population. In 2010, the revision rate reached 4.41%, representing an annual growth of 0.04% compared to 2009. During the period 2003-2010, the overall TKA revision rate was 3.62%. In 2010, primary bicondylar arthroplasty was the chosen TKA technique in 85.53% of all cases: 97.04% of all implants were fixed with bone cement, 1.36% were uncemented and 1.59% of all knees were hybrids. PMID:22243690

Ne?as, L; Katina, S; K?ivánek, S; Uhlárová, J



Anterior dislocation after a posterior stabilized total knee arthroplasty.  


Dislocation of a total knee arthroplasty is a rare but serious complication. In previous literature, when dislocation does occur, it is usually in the posterior direction in cases with a posterior stabilized total knee arthroplasty due to cam jump. We report an unusual case of anterior dislocation of an 11-year-old posterior stabilized total knee arthroplasty in a 55-year-old woman with rheumatoid arthritis occurred after a slip. PMID:21641178

Lee, Su Chan; Jung, Kwang Am; Nam, Chang Hyun; Hwang, Seung Hyun; Lee, Won Jun; Park, Il Seok



Total knee arthroplasty for post-traumatic arthrosis  

Microsoft Academic Search

The outcomes of total knee arthroplasty for post-traumatic arthrosis were studied in 31 knees. The average age at arthroplasty was 60 years old (range, 36–78 years). The interval from fracture to total knee arthroplasty averaged 13 years. Simultaneous corrective osteotomy was necessary in 4 patients to correct axial alignment and preserve ligamentous integrity. Follow-up averaged 46 months. Mean arc of

Jess H. Lonner; Frank X. Pedlow; John M. Siliski



Unmet Needs and Waiting List Prioritization for Knee Arthroplasty  

PubMed Central

Background There is a high volume of unmet needs for knee arthroplasty in the population despite the increase in surgery rates. Given the long waiting times to have a knee arthroplasty, some governments have proposed prioritization systems for patients on waiting lists based on their level of need. Questions/Purposes We therefore estimated the needs and demand of knee arthroplasty in four regions of Spain during a 5-year period. Methods We developed a discrete event simulation model to reproduce the process of knee arthroplasty. The prioritization system was compared with the usual waiting list management strategy (by waiting time only). Results Under the prioritization system, patients saved an average of 4.5 months (95% confidence interval, 4.4–4.6 months) adjusted by level of need. The proportion of patients who experienced excessive waiting times was small and was associated with low levels of priority. The 5-year projection of the volume of unmet needs for knee arthroplasty remained stable; however, although the volume of need for the first knee arthroplasty decreased by 12%, the volume of need for an arthroplasty in the contralateral knee increased by 50%. Conclusions The data suggested the prioritization system was more beneficial than assigning surgery by waiting time only. The 5-year projection of the volume of unmet needs for knee arthroplasty remained stable, despite the increase in the need for contralateral knee arthroplasty. Level of Evidence Level II, economic and decision analyses. See Guidelines for Authors for a complete description of levels of evidence.

Comas, Merce; Roman, Ruben; Quintana, Jose Maria



Advances in hip arthroplasty in the treatment of osteonecrosis.  


Osteonecrosis of the femoral head is a devastating disease for which many patients will eventually require total hip arthroplasty. Standard total hip arthroplasties have historically had poor results in patients with osteonecrosis. More recently, reports have shown excellent results with second- and third-generation designs that incorporate advances in bearing technology. However, there are still certain subpopulations of patients (those with sickle cell disease, those with systemic lupus erythematosus, and those who have undergone renal transplantation) that have less than optimal results. Other hip arthroplasty alternatives include bipolar hemiarthroplasty, limited femoral resurfacing, and metal-on-metal resurfacing. Bipolar hemiarthroplasty historically and currently has consistently poor results in most studies and should be avoided in patients with osteonecrosis. In multiple reports, limited femoral arthroplasty has demonstrated reasonable midterm and long-term outcomes as a temporizing procedure, with results being less predictable than for standard total hip arthroplasty. Recently, ceramic-on-ceramic and metal-on-metal resurfacing hip arthroplasty has emerged as a viable option that has been used to treat patients with osteonecrosis of the femoral head, and several studies have shown promising short-term outcomes. Overall, however, recent studies have shown more optimal outcomes with hip arthroplasty than resurfacing hip arthroplasty, which makes standard hip replacements, as well as other arthroplasty alternatives, more attractive for young patients with this disease. PMID:17472309

Seyler, Thorsten M; Cui, Quanjun; Mihalko, William M; Mont, Michael A; Saleh, Khaled J



Enlarged transacromial superior approach with reverse shoulder arthroplasty for fractures  

PubMed Central

The authors describe a step-by-step technique for reverse total shoulder arthroplasty using arthrotomy via the enlarged transacromial superior approach. This technique seems ideal for reinsertion of the tuberosities and to ensure adequate postoperative tensional balance of the infraspinatus and the subscapularis, which is critical for the rotator cuffs to function properly and to achieve optimal arthroplasty stability. Reviewing these different steps helps understanding each rotator cuff individual component's contribution to achieve optimal arthroplasty stability and external rotation with a reverse shoulder arthroplasty.

Poignard, Alexandre; Bouhou, Mohamed; Homma, Yasuhiro; Hernigou, Philippe



Intestinal adaptation after ileal interposition surgery increases bile acid recycling and protects against obesity-related comorbidities.  


Surgical interposition of distal ileum into the proximal jejunum is a bariatric procedure that improves the metabolic syndrome. Changes in intestinal and hepatic physiology after ileal interposition (transposition) surgery (IIS) are not well understood. Our aim was to elucidate the adaptation of the interposed ileum, which we hypothesized, would lead to early bile acid reabsorption in the interposed ileum, thus short circuiting enterohepatic bile acid recycling to more proximal bowel segments. Rats with diet-induced obesity were randomized to IIS, with 10 cm of ileum repositioned distal to the duodenum, or sham surgery. A subgroup of sham rats was pair-fed to IIS rats. Physiological parameters were measured until 6 wk postsurgery. IIS rats ate less and lost more weight for the first 2 wk postsurgery. At study completion, body weights were not different, but IIS rats had reversed components of the metabolic syndrome. The interposed ileal segment adapted to a more jejunum-like villi length, mucosal surface area, and GATA4/ILBP mRNA. The interposed segment retained capacity for bile acid reabsorption and anorectic hormone secretion with the presence of ASBT and glucagon-like-peptide-1-positive cells in the villi. IIS rats had reduced primary bile acid levels in the proximal intestinal tract and higher primary bile acid levels in the serum, suggesting an early and efficient reabsorption of primary bile acids. IIS rats also had increased taurine and glycine-conjugated serum bile acids and reduced fecal bile acid loss. There was decreased hepatic Cyp27A1 mRNA with no changes in hepatic FXR, SHP, or NTCP expression. IIS protects against the metabolic syndrome through short-circuiting enterohepatic bile acid recycling. There is early reabsorption of primary bile acids despite selective "jejunization" of the interposed ileal segment. Changes in serum bile acids or bile acid enterohepatic recycling may mediate the metabolic benefits seen after bariatric surgery. PMID:20595624

Kohli, Rohit; Kirby, Michelle; Setchell, Kenneth D R; Jha, Pinky; Klustaitis, Kori; Woollett, Laura A; Pfluger, Paul T; Balistreri, William F; Tso, Patrick; Jandacek, Ronald J; Woods, Stephen C; Heubi, James E; Tschoep, Matthias H; D'Alessio, David A; Shroyer, Noah F; Seeley, Randy J



Hepatic encephalopathy verified by psychometric testing and EEG in cirrhotic patients: Effects of mesocaval interposition shunt or sclerotherapy  

PubMed Central

Background. The aim of this randomised prospective study was to evaluate hepatic encephalopathy after mesocaval interposition shunt operation and after repeated endoscopic sclerotherapy. Methods. Forty-five patients with bleeding oesophageal varices due to liver cirrhosis were randomised to the two treatment groups, 24 to the shunt group and 21 to the sclerotherapy group. The patients were evaluated preoperatively regarding blood tests, hepatic encephalopathy as measured by electroencephalogram with spectral analysis and by a battery of psychometric tests. The direction of portal flow in the shunt group was investigated by shunt phlebography and ultrasonography with Doppler. During follow-up the same investigations were performed twice at median 6.7 and 14.7 months after operation. Results. No statistically significant difference was found during follow-up regarding blood tests and electroencephalography with spectral analysis. Although the preoperative psychometric tests showed that the shunt group performed significantly better than the sclerotherapy group, the first follow-up showed that the shunt group performed statistically worse than the sclerotherapy group in seven of the tests: Synonyms (measuring verbal ability), Block Design Test (measuring visuo-spatial ability), Memory for Design Test, Error Score (measuring memory function), Revised Visual Retention Test, correct answers and the same test error answers (measuring visuo-spatial memory, ability and immediate memory), Digit Symbol Test (measuring perceptual ability) and Trial Making Test B (measuring cognitive motor abilities). Conclusions. Patients treated by mesocaval interposition shunt showed a progressive general reduction in psychometric performance compared with patients treated with repeated sclerotherapy, in whom a general intellectual improvement was observed. This finding corresponds to the reverse direction of the preoperative portal flow to a hepatofugal pattern at first follow-up and at 12 months among two-thirds of the patients.

Thorell, L.-H.; Bengtsson, F.; Rosen, I.; Jeppsson, B.



Distraction arthroplasty of the trapeziometacarpal joint.  


Trapeziometacarpal distraction arthroplasty is a surgical technique for the treatment of trapeziometacarpal arthrosis. It consists of distracting the first metacarpal and then anchoring it in suspension to the second metacarpal by means of a tendon graft. Both a reduction of the subluxation of the base of the first metacarpal and an opening or distraction of the trapeziometacarpal joint, with a clear decrease in the forces of attrition on its joint surfaces, are thereby obtained. Compared with the traditional techniques of arthroplasty, this technique avoids trapeziectomy; it is therefore less destructive and is quicker and easier to carry out. It appears to be equally effective regarding pain, correcting the deformity, and recovering grip strength. PMID:17996782

Bufalini, Carlo; Perugia, Dario



Postoperative management for PIP joint pyrocarbon arthroplasty.  


Although protocols provide therapists with the scaffolding with which to build a treatment program, it is the judgment, knowledge, and skills of the therapist, and how the one uses such information that allows for modification of a protocol when deemed necessary. This therapist outlines how she modified a postsurgical protocol by using anatomy, biomechanics, the literature, and clinical judgment. This article describes the methodical approach used to successfully modify a standard postsurgical protocol after a PIP joint arthroplasty. PMID:20036511

Feldscher, Sheri B



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



Physical Activity After Total Joint Arthroplasty  

PubMed Central

Context: Total joint arthroplasty (TJA) is a common surgical option to treat painful degenerative joint disease. However, there is currently no consensus on the appropriate intensity of physical activity after TJA or how physical activity level affects the rate of revision surgery. Materials and Methods: A systematic review of the literature regarding physical or athletic activity after TJA was performed to determine current clinical opinion and recommendations regarding appropriate activity levels after TJA, as well as variables affecting successful surgery and improved outcomes. Results: Many studies in the literature regarding athletic activity after TJA focus on total hip arthroplasty and total knee arthroplasty. The literature reports contradictory results regarding rates of physical activity after TJA as well as the relationship between physical activity and rates of revision surgery. The current trend in expert opinion shows more liberal recommendations for patients to engage in athletic activity after TJA. Conclusions: Individual characteristics, lifestyle, and patient preferences must be taken into account when one considers appropriate recommendations for athletic activity after TJA. Current trends in clinical opinion favor a higher level of athletic activity after TJA, but clinicians should caution patients not to participate in contact sports or sports that create high joint loads in the replaced joint.

Vogel, Laura A.; Carotenuto, Giuseppe; Basti, John J.; Levine, William N.



Cervical arthroplasty for myelopathy adjacent to previous multisegmental fusion  

Microsoft Academic Search

In recent years, there has been increasing interest in the use of cervical arthroplasty for the treatment of degenerative cervical pathology. In its relative infancy, the applications for this technique are still being explored. In this report, we present the use of cervical arthroplasty in the treatment of progressive cervical myelopathy due to adjacent segment disease related to previous multisegmental

Ralph J. Mobbs; Nicholas Mehan; Peter Khong



History and design considerations for arthroplasty around the wrist.  


The history and evolution of both soft tissue and implant arthroplasty about the wrist are discussed, including carpometacarpal, radiocarpal, and distal radioulnar joints. Technical considerations for arthroplasty are reviewed, including factors affecting implant osseointegration, implant articulation/constraint, and management of complications. PMID:23168024

Rosenfeld, Jonathan F; Nicholson, James J



Joint stability after total shoulder arthroplasty in a cadaver model  

Microsoft Academic Search

A cadaver model was used to test the hypothesis that glenohumeral joint stability is independent of articular surface conformity after total shoulder arthroplasty. For the purposes of this study joint stability was defined as the minimum force required for joint dislocation. After arthroplasty components were implanted into fresh-frozen glenohumeral joints, specimens were mounted on a load frame and tested for

Andrew R Karduna; Gerald R Williams; John L Williams; Joseph P Iannotti



[Revision arthroplasty of the ankle joint].  


In the last 20 years total ankle replacement has become a viable alternative to arthrodesis for end-stage osteoarthritis of the ankle. Numerous ankle prosthesis designs have appeared on the market in the past and attracted by the encouraging intermediate results reported in the literature, many surgeons have started to perform this procedure. With increased availability on the market the indications for total ankle replacement have also increased in recent years. In particular, total ankle replacement may now be considered even in younger patients. Therefore, despite progress in total ankle arthroplasty the number of failures may increase. Up to now, arthrodesis was considered to be the gold standard for salvage of failed ankle prostheses. Because of extensive bone loss on the talar side, in most instances tibiocalcaneal fusion is the only reliable solution. An alternative to such extended hindfoot fusions would be revision arthroplasty. To date, however, there are no reported results of revision arthroplasty for salvage of a failed ankle replacement.Based on our experience prosthetic components with a flat undersurface are most likely to be able to find solid support on remaining bone stock. The first 83 cases (79 patients, 46 males, 33 females, average age 58.9 years, range 30.6-80.7 years) with a average follow-up of 5.4 years (range 2-11 years) showed excellent to good results in 69 cases (83%), a satisfactory result in 12 cases (15%) and a fair result in 2 cases (2%) and 47 patients (56%) were pain free. Primary loosening was noted in three cases and of these two cases were successfully revised by another total ankle replacement and in one case with arthrodesis. Another case with hematogenous infection was also revised by arthrodesis. At the last follow-up control two components were considered to be loose and the overall loosening rate was thus 6%.This series has proven that revision arthroplasty can be a promising option for patients with failed total ankle prosthesis. The most challenging issue is the solid anchoring of available components on residual bone. More experience is needed, however, to better define the possibilities and limitations of revision arthroplasty. PMID:21996936

Hintermann, B; Barg, A; Knupp, M



Effects of Mosapride Citrate on Patients after Vagal Nerve Preserving Distal Gastrectomy Reconstructed by Interposition of a Jejunal J Pouch with a Jejunal Conduit for Early Gastric Cancer  

Microsoft Academic Search

Background  Vagal nerve–preserving distal gastrectomy reconstructed by interposition of a jejunal J pouch with a jejunal conduit (hereinafter\\u000a called DGP) is a function-preserving operation for early gastric cancer. However, some patients after DGP have suffered from\\u000a postprandial stasis in the substitute stomach, and postprandial stasis leads to abdominal symptoms. To clarify the significance\\u000a of mosapride citrate (MS) for prevention of food

Ryouichi Tomita; Taro Ikeda; Shigeru Fujisaki; Tugumichi Koshinaga; Katsuhisa Tanjoh



Orthopaedic crossfire--can we justify unicondylar arthroplasty as a temporizing procedure? in opposition.  


The indications for unicompartmental arthroplasty are quite specific. Overall, there should be involvement of 1 tibiofemoral compartment, mild malalignment, and ligamentous stability. In a review of 250 osteoarthritic knees, these pathologic findings were present in 19 patients (8%). Technique, despite improvement in instrumentation, still is more demanding than tricompartmental knee arthroplasty, and failure to achieve an optimal arthroplasty occurs more frequently. In the literature, long-term results with unicompartmental arthroplasty have been inferior to tricompartmental arthroplasty. The concept that unicompartmental arthroplasty is a temporizing procedure is not a valid one in that the patient has to undergo another arthroplasty with all the risks of revision arthroplasty surgery. Many of these revision procedures require bone grafting or component augmentation. Tibial osteotomy remains the procedure of choice in younger, active patients with unicompartmental arthritis (in highly selected patients), and tricompartmental arthroplasty is preferred in older, lower demand patients. PMID:12068406

Sculco, Thomas P



An intraoperative pressure-measuring device used in total knee arthroplasties and its kinematics correlations.  


Fluoroscopic and retrieval analyses of knee implants show considerable variability even for the same implant design, and implicate the possible importance of surgical technique and compartment pressure balance in total knee arthroplasties. This study was done to correlate intraoperative computer-assessed compartment pressure measurements with postoperative kinematics to explain these variations. Thirty-eight patients had posterior cruciate-sacrificing low-contact stress total knee arthroplasties using a balanced gap technique. At trial reduction, an instrumented tibial insert designed to record the magnitude, location, and dynamic imprint of the pressures in the medial and lateral compartments was placed into the knee. Pressures were recorded electronically for a range of motion from 0 degrees - 120 degrees. Sixteen of the 38 patients agreed to do successive weightbearing deep knee bends under fluoroscopic surveillance. Only three of the 16 patients had condylar lift-off, but all experienced lift-off at a single flexion angle. In the three patients who had condylar lift-off, a compartment pressure imbalance, as measured by the intraoperative pressure sensor, occurred at the same flexion angle of lift-off. These data suggest that although a given implant design may have inherent kinematic tendencies, surgical technique and compartment pressure balance significantly impact kinematic performance. PMID:15552154

Wasielewski, Ray C; Galat, Daniel D; Komistek, Richard D



Behind the Pay Gap  

ERIC Educational Resources Information Center

|Women have made remarkable gains in education during the past three decades, yet these achievements have resulted in only modest improvements in pay equity. The gender pay gap has become a fixture of the U.S. workplace and is so ubiquitous that many simply view it as normal. "Behind the Pay Gap" examines the gender pay gap for college graduates.…

Dey, Judy Goldberg; Hill, Catherine



Triggered vacuum gaps  

Microsoft Academic Search

Characteristics of a sealed vacuum gap are described and the difficulties encountered in applying this gap as an overvoltage protection device are discussed. It is shown how these difficulties can be ameliorated by the use of gas-free electrode materials and by triggering the gap when breakdown is required. Several methods of triggering are discussed and some practical triggering devices are

J. M. Lafferty



Results with navigated bicontact total hip arthroplasty.  


The position of the cup is crucial for the overall quality of a total hip arthroplasty. A malpositioning of the cup leads to increased risk of dislocation, wear, and revision. The position of the stem influences leg length and may cause impingement and dislocation. These faults may increase with minimally invasive procedures. From November 2001 to June 2005, 1081 consecutive THA patients were evaluated. Cup navigation resulted in a better alignment and additional improvement when the cup and stem were navigated. In stem navigation, a good control of the leg lengthening and a reliable prediction of the safe range of motion could be seen. PMID:16235445

Lazovic, Djordje; Kaib, Niels



Bicompartmental knee arthroplasty: the clinical outcomes.  


Replacement of the patellofemoral and medial tibiofemoral joints has been performed since the 1980s. Bicompartmental replacement was modified. Two different designs were developed: one custom implant and one with multiple predetermined sizes. The surgical technique and instruments are unique and training is helpful. There are no clinical reports for the custom design as of yet. The standard implant has several reports in the literature with only fair to good results and has subsequently been withdrawn from the market. Bicompartmental arthroplasty remains a questionable area of knee surgery. At present, the two separate implant technique is the best choice. PMID:23827832

Tria, Alfred J



Medicolegal aspects of hip and knee arthroplasty.  


Hip and knee arthroplasties usually are satisfying for the patient and the surgeon; however, these procedures also have considerable risks for generating a medical malpractice lawsuit. Strict adherence to the standard of care and recently implemented patient safety strategies should reduce the surgeon's liability. Expert technical execution of the surgery, timely evidence-based patient treatment, and detailed documentation in the medical record will not only improve the quality of patient care but also will serve as a strong legal defense should the need arise. PMID:15805939

Attarian, David E; Vail, Thomas Parker



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


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



No clinical difference between large metal-on-metal total hip arthroplasty and 28-mm-head total hip arthroplasty?  

Microsoft Academic Search

Purpose  We aimed to test the claim of greater range of motion (ROM) with large femoral head metal-on-metal total hip arthroplasty.\\u000a \\u000a \\u000a \\u000a Methods  We compared 28-mm metal-on-polyethylene (MP) total hip arthroplasty with large femoral head metal-on-metal (MM) total hip\\u000a arthroplasty in a randomised clinical trial. ROM one year postoperatively was determined in 50 patients. Mean head sizes were\\u000a 28 mm (MP) and 48 mm (MM).

Wierd P. Zijlstra; Inge van den Akker-Scheek; Mark J. M. Zee; Jos J. A. M. van Raay


Comparative pooled survival and revision rate of austin-moore hip arthroplasty in published literature and arthroplasty register data.  


The aim was to evaluate the pooled survival and revision rate of Austin-Moore hip arthroplasty (AMHA) in published literature and arthroplasty register data. A comprehensive literature analysis of clinical publications and register reports was conducted with the main endpoints revision surgery and revision rate. Sixteen relevant clinical studies have been found to significantly underestimate revision rates by a ratio of 2.15 compared to register data sets. The medium-term outcome of AMHA showed significantly worse outcomes than the use of other bipolar implants, or modular cervicocephalic prostheses and data of journal publications on revision rates deviate significantly from data of arthroplasty registers. PMID:23535284

Sadoghi, Patrick; Thaler, Martin; Janda, Wolfgang; Hübl, Michael; Leithner, Andreas; Labek, Gerold



Bilateral condyle fracture of tibial insert in mobile bearing total knee arthroplasty.  


We report a case of polyethylene insert breakage in a 45-year-old man after 3.5years of cruciate retaining type mobile bearing total knee arthroplasty (TKA). Interstingly, both condyles of the polyethylene insert have fractured. The visual assessment done by stereoscopic microscope in the investigation report suggested that the fracture propagation was a result of cyclic loading and that the fracture was from the articular surface as a result of tibio-femoral and anteroposterior shear loading. The initial flexion-extension gap mismatch and/or specific Asian habits like kneeling or deep knee bending could have been the possible factors for over-stress for the insert causing this complication. After replacement of the broken insert and modification for daily activity preventing deep knee flexion, the patient obtained complete relief of previous symptoms. It remains unclear whether insert breakage was secondary to polyethylene insufficient design or to the polyethylene material fracture propagation. PMID:23340095

Yoon, Jung-Ro; Jeong, Hyeon-Il; Oh, Kwang-Jun; Yang, Jae-Hyuk



Paradoxical cerebral embolism after total knee arthroplasty.  


Deep vein thrombosis is a frequent complication following total joint arthroplasty and other major orthopedic procedures. Pulmonary embolism occurs with or without a diagnosis of deep vein thrombosis, although infrequently (1.5%-10%). In patients with congenital cardiac defects, such as a patent foramen ovale, paradoxical cerebral embolism may also occur. This article describes a case of a 52-year-old woman who sustained a paradoxical cerebral embolism following total knee arthroplasty. In the workup of a patient with a known murmur and stroke symptoms, paradoxical cerebral embolism should be included in the differential. The initial evaluation should incorporate transesophageal echocardiography because of its accuracy in the demonstration of the cardiac physiology. An abnormal intracardiac or intrapulmonary shunt is essential for paradoxical cerebral embolism, allowing the entrance of the thrombus into cerebral circulation from the venous system. No clear consensus has been reached on the management of patients at risk for paradoxical cerebral embolism prior to orthopedic procedures. However, when an embolic stroke is diagnosed acutely, ideal management includes thrombolytic therapy, but further research is needed to confirm that this is the correct management. Due to the risk of recurrence, postoperative thromboprophylaxis is recommended with or without closure of the foramen ovale. Most importantly, and as demonstrated by the current patient, who partially recovered but did not require walking assistance after 2-year follow-up, treating physicians should be prepared to counsel patients through a lengthened physical rehabilitative process. PMID:23127461

Hill, Brian W; Huang, Hanwei; Li, Mengnai



Wound problems in total knee arthroplasty.  


Wound problems can often be prevented with careful planning. When transverse incisions are used for knee surgery many years prior to any anticipated knee arthroplasty, no major problems are typically encountered with a conventional, anterior longitudinal incision. We recommend lateral incisions (eg, after a previous lateral tibial plateau fracture) be reused for TKA. When confronted with multiple previous incisions, surgeons would best use the most recently healed or the most lateral. We prefer soft tissue reconstruction with expanders or a gastrocnemius flap if there are multiple incisions, if the skin and scar tissue are adherent to underlying tissue, or if wound healing seems questionable. Deep infection must be determined by aspiration. When present, we believe treatment must include irrigation, débridement, polyethylene exchange if acute, and resection arthroplasty if chronic. Poor wound healing is a potentially devastating complication that may result in multiple reconstructive procedures and even amputation. Early recognition followed by expeditious débridement and soft tissue reconstruction should be used for managing wound complications after TKA. PMID:17079990

Vince, Kelly G; Abdeen, Ayesha



Enhanced recovery program in total hip arthroplasty  

PubMed Central

Background: Enhanced recovery program (ERP) was implemented to optimize the hospital stay in total hip arthroplasty. This study assessed the effects of optimizing preoperative and perioperative care using enhanced recovery (ER) on patients undergoing Total hip arthroplasty. Materials and Methods: We compared a prospective group of 64 patients on the ER program with a historic cohort of 63 patients that received conventional care (non ER). Results: ER patients were discharged earliest from hospital [mean length of stay (LOS) 5.3 days, median 4; P < 0.001] as compared to a mean of 8.3 days among non ER patients. Comparison based on American Association of Anesthesiologists (ASA) grades, preoperative hemoglobin, and body mass index (BMI) revealed that patients with ASA grade 3, preoperative hemoglobin of <14 g/dl, and BMI >30 on ER program spent shorter time in hospital as compared to the non ER's conventionally treated patients with more favorable physiological parameters of ASA grade 1 and 2, preoperative hemoglobin of >14 g/dl, and BMI <30. Conclusion: The ER protocol is universally beneficial and confers an advantage regardless of the patients’ preoperative condition.

Dwyer, Amitabh J; Tarassoli, Payam; Thomas, William; Porter, Paul



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.

Hamilton, Henry; Jamieson, John



Clinical pathway management of total knee arthroplasty.  


Using a retrospective cohort study design, the authors examined complications, readmissions, morbidity and mortality, and function scores in two groups of patients attended by the same surgeon for the year before and the year after the implementation of an outcomes management program with clinical pathways for patients undergoing total knee arthroplasty at an academic health center. The effectiveness of the pathway constantly was adjusted using variance analysis and continuous quality improvement techniques. This program reduced the length of stay by 57% from a premanagement value of 10.9 +/- 5.4 days in 1994 (Group 1) to 4.7 +/- 1.4 days in 1996 (Group 2). Hospital costs (based on an inflation adjusted cost to charge ratio) for all total knees were reduced 11% from $13,328 +/- $3905 in 1994 to $11,862 +/- $4763 in 1996. Preoperative and postoperative knee scores were 41.1 +/- 16.3 and 84.2 +/- 16.0 for Group 1 and 42.5 +/- 13.0 and 87.0 +/- 10.4 for Group 2, respectively. There was no statistically significant difference between the preoperative or the postoperative knee scores of Groups 1 and 2. The application of clinical pathways, variance analysis, and continuous quality improvement toward the treatment of patients who had total knee arthroplasty at an academic health center resulted in significant savings in length of stay without adversely affecting overall outcome. PMID:9418629

Mabrey, J D; Toohey, J S; Armstrong, D A; Lavery, L; Wammack, L A



Painful knee arthroplasty: definition and overview  

PubMed Central

Summary Total Knee Arthroplasty (TKA) is one of the most successful procedures in Orthopaedic Surgery, with good clinical results and high survival rate in more than 90% of the cases at long-term follow-up. Since the increase of population’s mean age, worsening of articular degenerative alterations, and articular sequelae related to previous fractures, there is a persistent growing of the number of knee arthroplasties in every country each year, with expected increase of complications rates. Painful TKA is considered an unusual complication, but several reports focus on this challenging clinical issue. Common causes of painful TKA may be divided as early or late, and in referred, periarticular or intra-articular. Among the early, we recall implant instability (related to surgical and technical mistakes) and problems of extensor mechanism (patella not resurfaced, malalignment of femoral, tibial, or patellar component, tendons failure or degeneration). Late causes of painful TKA are almost related to aseptic loosening and infection, but also, even if unusual, reflex sympathetic dystrophy, synovitis, and hypersensitivity to metal implants are represented. Hypersensitivity to metal is a clinical issue with significative increase, but to date without a specific characterization. The Authors report about incidence, clinical features, and diagnostic pathways of hypersensitivity to metal implants, focusing on the prevention of this challenging problem.

Carulli, Christian; Villano, Marco; Bucciarelli, Giovanni; Martini, Caterina; Innocenti, Massimo



Rural vs. urban utilization of total joint arthroplasty.  


The purpose of this study was to analyze the association between patient demographics and hospital demographics on utilization of total joint arthroplasty in rural and urban populations from the National Inpatient Sample database. Any patient that was discharged after a primary total hip or primary total knee arthroplasty was included in this study. Results showed that rural patients living in a Northeastern hospital region compared to West, less than 65 years of age, females, Blacks and Hispanics were less likely to undergo total joint arthroplasty compared to their urban counterparts. Rural patient were more likely to undergo total joint arthroplasty compared to their urban counterparts if they were in the Midwest and had Medicare as their primary payer provider. PMID:23541869

Banerjee, Devraj; Illingworth, Kenneth David; Novicoff, Wendy M; Scaife, Steven L; Jones, Braden K; Saleh, Khaled J



Clinical experience with computer navigation in revision total hip arthroplasty.  


The biomechanically and anatomically correct placement of hip prostheses components is the main challenge in revision hip arthroplasty. The orientation of the cup and stem with the restoration of leg length, offset and hip centre is hampered by the defect situations frequently present. In primary hip arthroplasty, it has been demonstrated that the components can be accurately positioned using computer-navigated procedures. However, such procedures could also be of considerable benefit in revision hip arthroplasty. Systems that not only detect anatomical landmarks using pointers but also use image data for referencing may provide a possible solution for the defect situation. Literature about navigation in revision arthroplasty is very rare. This article comprises general considerations on this subject and presents our experience and possible clinical applications. PMID:23636955

Franke, Jochen; Zheng, Guoyan; Wendl, Klaus; Grützner, Paul A; von Recum, Jan



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.

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



Primary versus secondary distal femoral arthroplasty for treatment of total knee arthroplasty periprosthetic femur fractures.  


Current methods of fixing periprosthetic fractures after total knee arthroplasty (TKA) are variable, and include open reduction and internal fixation (ORIF) via plating, retrograde nailing, or revision using standard revision TKA components or a distal femoral arthroplasty (DFA). The purpose of this study is to compare patients who failed plating techniques requiring subsequent revision to DFA to patients who underwent primary DFA. Of the 13 patients (9.2%) who failed primary ORIF, causes included nonunion (53.8%), infection (30.8%), loosening (7.7%), and refracture (7.7%). There were significantly more surgical procedures for ORIF revision to DFA compared to primary DFA. Complications for patients who underwent primary reconstruction with DFAs included extensor mechanism disruption (8.3%), infection (5.6%), and dislocation (2.8%). Primary reconstruction via ORIF is beneficial for preserving bone stock, but primary DFA may be preferred in osteopenic patients, or those at high risk for nonunion. PMID:23540541

Chen, Antonia F; Choi, Lisa E; Colman, Matthew W; Goodman, Mark A; Crossett, Lawrence S; Tarkin, Ivan S; McGough, Richard L



Unicompartmental Knee Arthroplasty Enables Near Normal Gait at Higher Speeds, Unlike Total Knee Arthroplasty  

PubMed Central

Top walking speed (TWS) was used to compare UKA with TKA. Two groups of 23 patients, well matched for age, gender, height and weight and radiological severity were recruited based on high functional scores, more than twelve months post UKA or TKA. These were compared with 14 preop patients and 14 normal controls. Their gait was measured at increasing speeds on a treadmill instrumented with force plates. Both arthroplasty groups were significantly faster than the preop OA group. TKA patients walked substantially faster than any previously reported series of knee arthroplasties. UKA patients walked 10% faster than TKA, although not as fast as the normal controls. Stride length was 5% greater and stance time 7% shorter following UKA — both much closer to normal than TKA. Unlike TKA, UKA enables a near normal gait one year after surgery.

Wiik, Anatole V.; Manning, Victoria; Strachan, Robin K.; Amis, Andrew A.; Cobb, Justin Peter



Accuracy of Computer-Navigated Total Hip Arthroplasty  

Microsoft Academic Search

Proper acetabular cup orientation is essential in total hip arthroplasty. The purpose of this study was to evaluate the accuracy of a particular imageless computer navigation system in determining cup position. Thirty-nine computer-navigated total hip arthroplasty intraoperative measurements of cup abduction and anteversion were compared with those from follow-up radiographs. Sensitivity, specificity, accuracy, prevalence-adjusted positive value (PPV), and negative predictive

Garrett M. Snyder; Santiago A. Lozano Calderón; Paul A. Lucas; Scott Russinoff


Evaluating comorbidities in total hip and knee arthroplasty: available instruments  

Microsoft Academic Search

Each year millions of patients are treated for joint pain with total joint arthroplasty, and the numbers are expected to rise.\\u000a Comorbid disease is known to influence the outcome of total joint arthroplasty, and its documentation is therefore of utmost\\u000a importance in clinical evaluation of the individual patient as well as in research. In this paper, we examine the various

Kristian BjorgulWendy; Wendy M. Novicoff; Khaled J. Saleh



Catastrophic Failure of Ceramic-Polyethylene Bearing Total Hip Arthroplasty  

Microsoft Academic Search

Complications of ceramic-polyethylene bearing total hip arthroplasty (THA) include osteolysis, loosening, dislocation, and component failure. Catastrophic acetabular component failure involves severe damage to both the polyethylene liner and metal shell. This case study presents the first reported complete wear-through of the acetabular portion of a ceramic-polyethylene arthroplasty presenting as a dislocation and a review of the literature. In this study,

Justin Needham; Travis Burns; Tad Gerlinger



Small Stem Total Hip Arthroplasty in Hypoplasia of the Femur  

Microsoft Academic Search

Total hip arthroplasty in hypoplastic femurs is technically difficult and the incidence of complications and aseptic loosening\\u000a is relatively high. Cemented, uncemented, off-the-shelf, and custom-made stems all have been advocated in these cases. From\\u000a 1978 to 1997, we performed 86 total hip arthroplasties in 77 patients with a hypoplastic femur using a cemented, off-the-shelf,\\u000a small, curved, cobalt-chromium stem. We hypothesized

F. Harald R. De Man; Daniel Haverkamp; Harm M. Van der Vis; Philip P. Besselaar; René K. Marti



Radial head fractures: indications and outcomes for radial head arthroplasty.  


Radial head fractures without associated bony or ligamentous injury can be safely treated with internal fixation, if possible, or arthroplasty if nonreconstructable. However, nonreconstructable radial head fractures in association with elbow dislocation and/or ligamentous injury in the elbow or forearm represent a specific subset of injuries that requires restoration of the radiocapitellar articulation for optimal function. The purpose of this article was to summarize the indications for radial head arthroplasty and discuss the reported outcomes. PMID:23827844

Fowler, John R; Goitz, Robert J



Habitual Physical Activity and Sports Participation After Total Ankle Arthroplasty  

Microsoft Academic Search

Background: There is a lack of detailed information about habitual physical activity levels and the sports participation of patients after total ankle arthroplasty.Hypothesis: The proportion of sports active patients increases after total ankle arthroplasty, and the majority of patients will meet current recommendations for health-enhancing physical activity.Study Design: Case series; Level of evidence, 4.Methods: The authors assessed the pre- and

Florian D. Naal; Franco M. Impellizzeri; Markus Loibl; Martin Huber; Pascal F. Rippstein



Customized knee arthroplasty and the role of preoperative imaging.  


OBJECTIVE. The purpose of this article is to review advances in customized knee arthroplasty, highlighting advances in the use of preoperative imaging for component placement and design. CONCLUSION. Total knee arthroplasty is a highly successful surgical procedure. Although implant survivorship is generally excellent, failures do occur, and suboptimal component positioning is an important factor in implant failure. Surgical advances have focused on the use of advanced imaging and associated computer-assisted navigation to optimize component positioning. PMID:23971475

O'Connor, Mary I; Kransdorf, Mark J



Ureaplasma urealyticum infection in total hip arthroplasty leading to revision.  


We describe an infection with Ureaplasma urealyticum causing rapid loosening of a cemented total hip arthroplasty. When reviewing the literature we found that no such case has been reported previously. Taking intraoperative cultures for U urealyticum during revision surgery is not a standard procedure. In cases with rapid, presumed aseptic, loosening of a total hip arthroplasty, an infection with U urealyticum should be considered. PMID:20705423

Sköldenberg, Olof G; Rysinska, Agata D; Neander, Gustaf; Muren, Olle H; Ahl, Torbjörn E



Primary and revision total hip arthroplasty in osteogenesis imperfecta.  


Due to an increasing lifespan, patients with osteogenesis imperfecta have a high incidence of hip osteoarthritis. The presence of recurrent fractures and deformities make primary and particularly revision total hip arthroplasty challenging. We present a series of patients with osteogenesis imperfecta undergoing total hip arthroplasty at a tertiary referral centre with a median follow-up of 7.6 years (4 to 35 years). There were four primary total hip arthroplasties and eight revision total hip arthroplasties performed in four patients. Three femoral components were custom computer assisted design computer assisted manufactured. The survival rate of the primary total hip arthroplasty was 16% and there were ten complications: five intraoperative fractures, one case of septic loosening and four cases of aseptic loosening. Patients with pre-operative acetabular protrusio were significantly more likely to require revision surgery (p = 0.02). At latest follow-up, the median Oxford hip score was 41 (37 to 46). As the largest series of primary and revision total hip arthroplasty performed in patients with osteogenesis imperfecta, we report good medium to long-term outcomes. Preoperative planning and consideration of custom made prostheses have an important role in these complex cases. PMID:23329537

Krishnan, Harry; Patel, Nirav K; Skinner, John A; Muirhead-Allwood, Sarah K; Briggs, Timothy W; Carrington, Richard W; Miles, Jonathan



Digital versus analogue preoperative planning of total hip arthroplasties: a randomized clinical trial of 210 total hip arthroplasties.  


The objective of this randomized clinical trial was to compare the clinical and technical results of digital preoperative planning for primary total hip arthroplasties with analogue planning. Two hundred and ten total hip arthroplasties were randomized. All plans were constructed on standardized radiographs by the surgeon who performed the arthroplasty the next day. The main outcome was accuracy of the preoperative plan. Secondary outcomes were operation time and a radiographic assessment of the arthroplasty. Digital preoperative plans were more accurate in planning the cup (P < .05) and scored higher on the postoperative radiologic assessment of cemented cup (P = .03) and stem (P < .01) components. None of the other comparisons reached statistical significance. We conclude that digital plans slightly outperform analogue plans. PMID:17826278

The, Bertram; Verdonschot, Nico; van Horn, Jim R; van Ooijen, Peter M A; Diercks, Ron L



The anteromedial approach for shoulder arthroplasty: The importance of the anterior deltoid  

Microsoft Academic Search

Protection of the anterior aspect of the deltoid muscle is critical to the success of shoulder arthroplasty. Between 1975 and 1980, 75 patients with 81 shoulder arthroplasties had exposure via the anteromedial approach with careful anterior deltoid detachment through fascial tissues, systematic repair, and standardized rehabilitation with early passive range of motion. As with other reports on arthroplasty, pain was

David R. J. Gill; Robert H. Cofield; Charles Rowland



Replacement arthroplasty in the weight-bearing shoulder of paraplegic patients  

Microsoft Academic Search

We review the early results of shoulder arthroplasty in the weight-bearing shoulder of long-term paraplegic patients. We have been unable to find previously published results of this subgroup of shoulder arthroplasty patients in the literature. Five paraplegic, female patients who had undergone shoulder arthroplasty were analyzed. All patients had been prospectively assessed with the American Shoulder and Elbow Surgeons (ASES)

C Garreau De Loubresse; M. R Norton; P Piriou; G Walch



Spontaneous fracture of the ceramic ball in a ceramic—polyethylene total hip arthroplasty  

Microsoft Academic Search

Fractures of the ceramic ball in total hip arthroplasty are an uncommon cause of arthroplasty failure, and reports of this complication in ceramic-on-polyethylene total hip arthroplasty articulations are rare. Ball fractures have been reported in patients who were overweight, had high levels of activity, or had been injured. Other postulated contributory factors have included small ball diameter, defects in ceramic

R. J. Michaud; S. Y. Rashad



Alternative bearing surfaces in total hip arthroplasty.  


Polyethylene wear and extension of indications of total hip arthroplasty into younger and younger age groups have pushed manufacturers to develop more durable bearing surfaces. Standard polyethylene, the plastic used for the first 3 decades of hip replacement, virtually ceases to exist in its original form. Modifications of the processing, including sterlization in an inert environment and cross-linking, have demonstrated some improvements in wear. Hard-on-hard bearings such as ceramic-on-ceramic and metal-on-metal also have demonstrated extremely low wear. This article reviews the pros and cons of the alternative bearing options available to assist in the proper bearing selection for a particular patient. PMID:12882250

Inzerillo, V Christopher; Garino, Jonathan P



Popliteal artery injury after total knee arthroplasty.  


Total knee arthroplasty (TKA) is a commonly performed orthopedic procedure. The incidence of vascular complications after TKA is low. However, these complications may be debilitating, limb-threatening, and potentially avoidable. Our first patient, who had no preexisting vascular occlusive disease, developed an ischemic extremity after TKA. The second patient underwent TKA and was diagnosed with a severely ischemic limb 48 hours postoperatively. Both patients underwent above-knee to below-knee popliteal artery saphenous vein bypass grafting. Although limb salvage was obtained in both cases, one had a significantly neuropathic foot. In conclusion, long-term morbidity can be avoided by early identification and treatment of ischemia by bypass grafting. PMID:8615563

Mureebe, L; Gahtan, V; Kahn, M B; Kerstein, M D; Roberts, A B



Sources of error in total knee arthroplasty.  


The purpose of this study was to identify the procedural steps in a total knee arthroplasty (TKA) in which technical errors occur and to quantify the magnitude of these errors. Forty-nine consecutive TKAs were performed using a traditional exposure and manual instrumentation. An image-free computer navigation system (OrthoPilot; Aesculap AG, Tuttlingen, Germany) was used to measure and compare femoral and tibial alignment at specific procedural points during the TKA; this data was then used to evaluate possible sources of error in the procedure. The femoral cut tended to be made in hyperextension, the tibial cut tended to be made in hyperextension and valgus, and the tibial component tended to be implanted in valgus. This study identified specific points during the performance of a TKA where technical errors occur. This information suggests technical considerations that can help a surgeon achieve more reproducible, durable, and successful outcomes for his or her patients. PMID:19472971

Koyonos, Loukas; Stulberg, S David; Moen, Todd C; Bart, Gina; Granieri, Michael



Factors affecting bony impingement in hip arthroplasty.  


Computer modeling of 10 patients' computed tomographic scans was used to study the variables affecting hip arthroplasty range of motion before bony impingement (ROMBI) including acetabular offset and height, femoral offset, height and anteversion, and osteophyte removal. The ROMBI was compared with the ROM before component impingement and the native hip ROM. The ROMBI decreased with decreased total offset and limb shortening. Acetabular offset and height had a greater effect on ROMBI than femoral offset and height. The ROMBI lost with decreased acetabular offset was not fully recoverable with an increase in femoral offset or osteophyte removal. Bony impingement increased and component impingement decreased with decreased acetabular offset and increased head diameter. PMID:19559561

Kurtz, William B; Ecker, Timo M; Reichmann, William M; Murphy, Stephen B



Gap year volunteer tourism  

Microsoft Academic Search

The valorisation of cross-cultural understanding and promotion of an ethic of global citizenship are at the forefront of the recent development and proliferation of international ‘gap year’ travel programs and policies. Governments and industry alike promote gap year travel uncritically as a guaranteed pathway to the development of inclusive ideologies associated with global citizenship. In this paper we examine how

Stephen Wearing; John Neil


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



Bridging a Cultural Gap  

ERIC Educational Resources Information Center

|There has been a broad wave of change in tertiary calculus courses in the past decade. However, the much-needed change in tertiary pre-calculus programmes--aimed at bridging the gap between high-school mathematics and tertiary mathematics--is happening at a far slower pace. Following a discussion on the nature of the gap and the objectives of a…

Leviatan, Talma



Knowledge Gaps, Social Locators, and Media Schemata: Gaps, Reverse Gaps, and Gaps of Disaffection  

Microsoft Academic Search

In a study of a public school controversy, a knowledge gap is found that the authors describe as a gap of disaffection. Among women only, higher education leads to greater knowledge, but does so partly through reduced trust of government and lower perceived fairness of the news media. Similar findings occur with other less powerful groups.

Eric S. Fredin; Teresa Haugen Monnett; Gerald M. Kosicki




EPA Science Inventory

Resource Purpose: The information collected serves the following purposes: (1) provides a summary of funds allocated by tribe for the GAP Program, (2) provides an overview in the types of activities the tribes are engaged in with GAP funds, and (3) allows OW to document the...


Biostratigraphic gap analysis  

Microsoft Academic Search

Frequency distributions of biostratigraphic gaps are generated for eight fossil species. The distributions help estimate confidence intervals for biozonation boundaries by providing information on the size of the gap one may reasonably expect between the lowest and highest visible fossil occurrences, seen in cross section, and the actual lowest and highest individuals, unseen within the rock, which occur beyond them.

Michael L. McKinney



Treatment of infected total knee arthroplasty.  


Cementless revision arthroplasty using allograft technique for massive tibial and femoral defects and delayed implantation after debridement was evaluated for the treatment of chronically infected total knee arthroplasties. Thirty-three knees in 33 patients were treated by implant removal and debridement followed by six weeks of antibiotic-impregnated cement beads and intravenous antibiotics. Cultures of synovial tissue taken at surgery grew Staphylococcus epidermidis in 18 knees, Staphylococcus aureus in five knees, Enterococcus in five knees, Pseudomonas in four knees, and mixed gram-negative organisms in one knee. Intravenous antibiotics were given accordingly. A painfree, nondraining wound was achieved with the first incision and drainage in 28 knees, whereas four knees required one or two subsequent procedures to achieve a dry wound and weight-bearing function. One knee continued to drain after repeated attempts at revision and fusion, and amputation above the knee was done at another institution. Cementless reconstruction using antibiotic-soaked bone graft and rigidly fixed femoral and tibial components was successful in 32 of 33 knees, with intermediate term follow-up examinations. Extensive debridement, followed by a six-week waiting period, produced a dry wound and pain-free knee in most patients. Those who developed recurrent infection responded well to repeat debridement, and all but one have remained free of clinically apparent infection two to eight years after surgery. Repeat debridement, antibiotic-impregnated cement beads, and bone grafting were uncommonly necessary, but the four patients that required them did not lose bone stock with subsequent revisions. All but one patient achieved stable fixation of the implants and good function of the knee.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8119013

Whiteside, L A



Favorable results after total wrist arthroplasty  

PubMed Central

Background and purpose During the past 40 years, several attempts have been made with total wrist arthroplasty to avoid fusion in severely destroyed wrists. The results have often been disappointing. There is only modest clinical documentation due to the small number of patients (especially non-rheumatoid cases) and short follow-up times. Here we report a multicenter series using a third-generation implant with a minimum follow-up time of 5 years. Methods In 2012, data were retrieved from a registry of consecutive wrist operations at 7 centers with units specialized in hand surgery, between 2003 and 2007. The wrists had been reviewed annually and analysis was done on the latest follow-up data. Results 60 patients had been operated (5 bilaterally), 5 wrists had been revised, and 52 were available for follow-up (with the revised cases excluded). The pain scores, QuickDASH scores, ulnar flexion, and supination for the whole group were statistically significantly better at follow-up. There were no statistically significant differences between the rheumatoid and the non-rheumatoid patients except for motion, which was better in the non-rheumatoid group. The motion obtained depended on the preoperative motion. Implant survival was 0.9 at 5–9 years. Interpretation The clinical results in terms of pain, motion, strength, and function were similar to those in previous reports. The implant survival was 0.9 at 9 years, both in rheumatoid and non-rheumatoid cases, which is an important improvement compared to the earlier generations of total wrist arthroplasty.

Boeckstyns, Michel E H; Herzberg, Guillaume; Merser, S?ren



The 'gap' in the 'plasma osmolar gap'.  


Ethylene glycol poisoning is a medical emergency that presents challenges for clinicians and clinical laboratories. If left untreated, it may cause morbidity and death, but effective therapy is available if diagnosed in time. The diagnosis of ethylene glycol poisoning is not always straightforward and the commonly quoted 'plasma osmolar gap' is not sufficiently sensitive to exclude a small ingestion and has been reported to be normal in a number of serious exposures. The 'plasma osmolar gap' cannot distinguish among ethanol, isopropyl alcohol, methanol or ethylene glycol. Thus, the measurement of serum ethylene glycol and, ideally, glycolic acid, its major toxic metabolite in serum, is definitive. This also holds true for methanol and its metabolite formic acid. Ethylene glycol metabolites target the kidney and lead to reversible oliguric or anuric injury, which in turn slows the elimination of ethylene glycol. The therapeutic options include reversal of metabolic acidosis, inhibition of alcohol dehydrogenase and early haemodialysis. PMID:23929610

Arora, Alok



Shoulder Arthroplasties have Fewer Complications than Hip or Knee Arthroplasties in US Veterans  

PubMed Central

Total shoulder arthroplasties (TSA) are being performed more commonly for treatment of arthritis, although fewer than either hip (THA) or knee (TKA) arthroplasties. Total shoulder arthroplasty also provides general health improvements that are comparable to THA. One study suggests TSAs are associated with lower morbidity and mortality than THAs and TKAs. To confirm and extend that study, we therefore examined the association of patient characteristics (sociodemographics, comorbid illness, and other risk factors) with 30-day complications for patients undergoing TSAs, THAs, or TKAs. We used data from the Veterans Administration (VA) National Surgical Quality Improvement Program (NSQIP) for fiscal years 1999 to 2006. Sociodemographics, comorbidities, health behaviors, operative factors, and complications (mortality, return to the operating room, readmission within 14 days, cardiovascular events, and infections) were available for 10,407 THAs, 23,042 TKAs, and 793 TSAs. Sociodemographic features were comparable among groups. The mean operative time was greater for TSAs (3.0 hours) than for TKAs (2.2 hours) and THAs (2.4 hours). The 30-day mortality rates were 1.2%, 1.1%, and 0.4% for THAs, TKAs, and TSAs, respectively. The corresponding postoperative complication rates were 7.6%, 6.8%, and 2.8%. Adjusting for multiple risk factors, complications, readmissions, and postoperative stays were less for TSAs versus THAs and TKAs. In a VA population, TSAs required more operative time but resulted in shorter stays, fewer complications, and fewer readmissions than THAs and TKAs. Level of Evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Mikuls, Ted R.; Michaud, Kaleb D.; Henderson, William G.; O'Dell, James R.





An improved triggered spark gap switch is described, capable of precisely controllable firing time while switching very large amounts of power. The invention in general comprises three electrodes adjustably spaced and adapted to have a large potential impressed between the outer electrodes. The central electrode includes two separate elements electrically connected togetaer and spaced apart to define a pair of spark gaps between the end electrodes. Means are provided to cause the gas flow in the switch to pass towards the central electrode, through a passage in each separate element, and out an exit disposed between the two separate central electrode elements in order to withdraw ions from the spark gap.

Neal, R.B.



Hip arthroplasty for failed treatment of proximal femoral fractures.  


Failed treatment of an intertrochanteric fracture typically leads to profound functional disability and pain. Salvage treatment with hip arthroplasty may be considered. The aim of this study was to evaluate the results and complications of hip arthroplasty performed as a salvage procedure after the failed treatment of an intertrochanteric hip fracture. Twenty-one patients were treated in our hospital with hip arthroplasty for failed treatment of intertrochanteric hip fracture. There were sixteen women and five men with a mean age of 75.8 years (range 61-85 years). Fourteen patients had failure of a previous nail fixation procedure, five had failure of a plate fixation, one of hip screws fixation and one of Ender nail fixation. In 19 out of 21 patients we performed a total hip arthroplasty-14 cases used modular implants with long-stems and five cases used a standard straight stem. In 2 of 21 cases we used a bipolar hemiarthroplasty. A statistically significant improvement was found comparing pre and postoperative conditions (p < 0.05). Our experience confirms that total hip arthroplasty is a satisfactory salvage procedure after failed treatment of an intertrochanteric fracture in elderly patients with few serious orthopaedic complications and acceptable clinical outcomes. PMID:19572131

D'Arrigo, Carmelo; Perugia, Dario; Carcangiu, Alessandro; Monaco, Edoardo; Speranza, Attilio; Ferretti, Andrea



Hip arthroplasty for failed treatment of proximal femoral fractures  

PubMed Central

Failed treatment of an intertrochanteric fracture typically leads to profound functional disability and pain. Salvage treatment with hip arthroplasty may be considered. The aim of this study was to evaluate the results and complications of hip arthroplasty performed as a salvage procedure after the failed treatment of an intertrochanteric hip fracture. Twenty-one patients were treated in our hospital with hip arthroplasty for failed treatment of intertrochanteric hip fracture. There were sixteen women and five men with a mean age of 75.8 years (range 61–85 years). Fourteen patients had failure of a previous nail fixation procedure, five had failure of a plate fixation, one of hip screws fixation and one of Ender nail fixation. In 19 out of 21 patients we performed a total hip arthroplasty—14 cases used modular implants with long-stems and five cases used a standard straight stem. In 2 of 21 cases we used a bipolar hemiarthroplasty. A statistically significant improvement was found comparing pre and postoperative conditions (p?arthroplasty is a satisfactory salvage procedure after failed treatment of an intertrochanteric fracture in elderly patients with few serious orthopaedic complications and acceptable clinical outcomes.

D'Arrigo, Carmelo; Carcangiu, Alessandro; Monaco, Edoardo; Speranza, Attilio; Ferretti, Andrea



Cervical arthroplasty: the beginning, the middle, the end?  


Cervical arthroplasty has developed as an alternative to spinal fusion for the treatment of cervical radiculopathy and myelopathy. The popularity of artificial discs has grown as the evidence of complications following arthrodesis has increased, making the theoretical advantages (motion preservation, altering the natural history of disease, prevention of adjacent segment disease) of disc replacement more attractive. However, as more discs are implanted and the length of follow-up increases, reported complications such as heterotopic ossification, device migration and spontaneous fusion of arthroplasty devices are growing. As a result, surgeons and patients face a challenge when deciding between motion-preserving or fusion surgery. Currently, there is inadequate evidence to promote extensive use of artificial discs for cervical spondylosis, despite promising short-term and intermediate clinical outcomes. However, there is also insufficient evidence to cease using them completely. The use of arthroplasty over fusion in the long term can only be justified if the incidence of adjacent segment disease decreases as a result. Despite the level of investment and research into arthroplasty outcomes, long-term follow-up has yet to be completed and has not convincingly demonstrated the effect of artificial discs on adjacent segment disease. Further long-term randomised trials are necessary to determine whether cervical arthroplasty is able to reduce the incidence of adjacent segment disease and, in doing so, replace arthrodesis as the gold standard treatment for cervical spondylosis. PMID:21815734

Richards, O; Choi, D; Timothy, J



Joint Arthroplasties other than the Hip in Solid Organ Transplant Recipients  

PubMed Central

Transplantation Surgery has undergone a great development during the last thirty years and the survival of solid organ recipients has increased dramatically. Osteo-articular diseases such as osteoporosis, fractures, avascular bone necrosis and osteoarthritis are relatively common in these patients and joint arthroplasty may be required. The outcome of hip arthroplasty in patients with osteonecrosis of the femoral head after renal transplantation has been studied and documented by many researchers. However, the results of joint arthroplasties other than the hip in solid organs recipients were only infrequently reported in the literature. A systematic review of the English literature was conducted in order to investigate the outcome of joint arthroplasties other than the hip in kidney, liver or heart transplant recipients. Nine pertinent articles including 51 knee arthroplasties, 8 shoulder arthroplasties and 1 ankle arthroplasty were found. These articles reported well to excellent results with a complication rate and spectrum comparable with those reported in nontransplant patients.

Sayed-Noor, Arkan S



The post-auricular approach for gap arthroplasty - a clinical investigation.  


Objective of this prospective study was to evaluate and compare posterior auricular approach for surgery of temporomandibular joint ankylosis with preauricular approach. These evaluations were done on the basis of certain parameters like incidences of facial nerve injury, time taken to expose ankylotic mass, haemorrhage and quality of exposure of joint and surrounding structures. This study was conducted among 15 patients of temporomandibular joint ankylosis. A total number of 30 joints were operated. These joints were divided in two groups i.e. Group A - preauricular group, Group B - postauricular group. Fifteen joints were operated in each group. Age of patients was in range of 4-65 years. All the patients were operated under general anesthesia. Preoperative, intraoperative and postoperative evaluations were done according to parameters. Patients were recalled up to 3 months for observations. Results have shown that in postauricular group incidences of facial nerve injury was significantly less, more time was taken to expose the ankylotic mass, incidences of haemorrhage was more and exposure of structures anterior to joint was difficult. Whereas preauricular approach is less time consuming, incidence of facial nerve damage is higher, exposure of structures anterior to joint is good and intraoperative incidences of haemorrhage is less. PMID:21944649

Bansal, Vishal; Kumar, Sanjeev; Mowar, Apoorva; Yadav, Anurag; Khare, Gagan



Short stem option for total hip arthroplasty with retained hardware.  


The presence of retained femoral hardware, usually as a consequence of prior orthopedic trauma, has been classically presented as something that must be removed prior to total hip arthroplasty. However, hardware removal is not without risks, including pain, creation of stress risers, and refracture. The authors report a patient with a retained retrograde femoral nail who underwent total hip arthroplasty with a short, neck-preserving femoral stem used to avoid the need for hardware removal. Clinical results at short-term follow-up have been excellent. In the setting of retained hardware, the use of short stems may be a viable treatment option for a well-selected subgroup of patients who require total hip arthroplasty and when the surgeon cannot use standard implants. PMID:24093688

Mont, Michael A; Pivec, Robert; Issa, Kimona; Harwin, Steven F



Radiographic and scintigraphic evaluation of total knee arthroplasty  

SciTech Connect

Various radiographic and scintigraphic methods are used to supplement clinical findings in the evaluation of total knee arthroplasty and its complications. Serial roentgenograms offer reliable information for diagnosing mechanical loosening. Wide and extensive radiolucency at the cement-bone interface and shift in position and alignment of prosthetic components can be seen in almost all cases by the time revision is necessary. Radiographic abnormalities are usually not present in acute infection, but are often present in chronic infection. Bone scanning has a high sensitivity for diagnosis of infection or loosening, but is nonspecific because increased uptake is often present around asymptomatic total knee arthroplasties with normal radiographs. Differential bone and Gallium scanning and scanning with Indium 111-labeled leukocytes have a greater specificity for diagnosis of infection than does bone or Gallium scanning alone. Routine radiographic and scintigraphic studies have shown a high incidence of deep vein thrombosis in the calf after total knee arthroplasty. Clinically significant pulmonary embolization is infrequent.

Schneider, R.; Soudry, M.



Cardiopulmonary Complications after Primary Shoulder Arthroplasty: A Cohort study  

PubMed Central

Objective Study the frequency and predictors of 90-day cardiopulmonary complications following primary shoulder arthroplasty Methods We used prospectively collected data from the Mayo Clinic Total Joint registry from 1976–2008. We used univariate and multivariable-adjusted Cox regression analyses to examine the association of age, gender, body mass index (BMI), comorbidity assessed by Deyo-Charlson index, American Society of Anesthesiologist (ASA) class, implant fixation (cemented versus not) and underlying diagnosis with the risk of 90-day cardiopulmonary complications after primary shoulder arthroplasty. Odds ratio (OR) with 95% confidence interval (CI) and p-values are presented. Results 3,480 patients underwent 4,019 primary shoulder arthroplasties. 90-day cardiac and thromboembolic complication rates following primary shoulder arthroplasty were 2.6% (92/3480) and 1.2% (42/3480). After multivariable-adjustment, age >70 years (OR, 2.7; 95% CI: 1.2–5.9; p-value= 0.01; relative to age <60), Deyo-Charlson comorbidity index of 1 or more (OR, 3.27; 95% CI:1.9–5.6; p<0.0001; relative to index of 0) and prior cardiac events (OR, 7.87; 95% CI: 4.89–12.68; p<0.0001; relative to no prior event) were associated with higher odds of 90-day cardiac complications. Due to few thromboembolic events, only univariate analyses were performed. Univariately, female gender, age >70 years, BMI 25–29.9 kg/m2, Deyo Charlson index of 1 or more, underlying diagnosis of trauma, prior thromboembolic event and surgery type were each associated with significantly higher risk of 90-day thromboembolic event (p?0.03 for all). Conclusions Cardiac and thromboembolic complications are uncommon after primary shoulder arthroplasty. Patients can be informed of their risk of cardiac complications following shoulder arthroplasty based on presence of risk factors.

Singh, Jasvinder A.; Sperling, John; Cofield, Robert



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)



Fungal prosthetic joint infection after total knee arthroplasty  

PubMed Central

Fungal prosthetic joint infection after total knee arthroplasty (TKA) is a rare complication. Lacunae exist in the management of this complication. 62 year old lady presented with pain and swelling in left knee and was diagnosed as Candida tropicalis fungal infection after TKA. She underwent debridement, resection arthroplasty and antifungal plus antibiotic loaded cement spacer insertion, antifungal therapy with fluconazole followed by delayed revision TKA and further fluconazole therapy. Total duration of fluconazole therapy was 30 weeks. At 2 year followup, she has pain less range of motion of 10°-90° and there is no evidence of recurrence of infection.

Reddy, Kankanala J; Shah, Jay D; Kale, Rohit V; Reddy, T Jayakrishna



Bilateral pseudogout 8 years after bilateral total knee arthroplasty.  


This article presents the clinical features of crystal arthropathy after knee replacement. The current literature on pseudogout and gout after both total and partial knee replacement is summarized. A case of bilateral pseudogout 8 years after initial total knee arthroplasty (TKA) is used to highlight the clinical characteristics and treatment options for this underrecognized condition. Presentation mimicked a late septic joint arthroplasty with sudden onset of pain and effusion. The patient was treated successfully with an arthrotomy, debridement, synovectomy, polyethylene insert exchange, oral steroids, and nonsteroidal anti-inflammatories. There are no other reported cases of bilateral pseudogout after bilateral TKA. PMID:23102423

Levi, Gabriel S; Sadr, Kamran; Scuderi, Giles R



Alternative bearings in total hip arthroplasty in the young patient.  


Total hip arthroplasty is an effective treatment option for advanced hip arthritis in elderly patients. Studies in young patients have traditionally shown less durable results. With current implants, surgical technique, and cementless fixation methods, the durability of total hip arthroplasty may now be related to the wear performance of the bearing surfaces. To improve implant longevity, there are several bearing surface choices currently available for this demanding group of patients. Alternatives must be evaluated in terms of the risks and benefits associated with each articulation, and all new technologies must be carefully monitored over the long term. PMID:24095062

Kamath, Atul F; Prieto, Hernan; Lewallen, David G



Compartment Syndrome Following Lower Limb Arthroplasty: A Review  

PubMed Central

Compartment syndrome is an urgent clinical entity characterised by an increase in the interstitial pressure within a closed osseofascial compartment. Although well recognised as a potential complication after orthopaedic trauma, it is very rarely presented after elective orthopaedic surgery and especially joint arthroplasty. In these rare cases a number of variables are associated with it (positioning, coagulopathy, extensive soft tissue dissection, previous scarring, and epidural analgesia). In this study we present the current evidence with regard to incidence and causation of compartment syndrome after lower limb joint arthroplasty and make recommendations on how to avoid the development of this devastating complication.

Lasanianos, Nikolaos G; Kanakaris, Nikolaos K; Roberts, Craig S; Giannoudis, Peter V



Fungal prosthetic joint infection after total knee arthroplasty.  


Fungal prosthetic joint infection after total knee arthroplasty (TKA) is a rare complication. Lacunae exist in the management of this complication. 62 year old lady presented with pain and swelling in left knee and was diagnosed as Candida tropicalis fungal infection after TKA. She underwent debridement, resection arthroplasty and antifungal plus antibiotic loaded cement spacer insertion, antifungal therapy with fluconazole followed by delayed revision TKA and further fluconazole therapy. Total duration of fluconazole therapy was 30 weeks. At 2 year followup, she has pain less range of motion of 10(°)-90(°) and there is no evidence of recurrence of infection. PMID:24133317

Reddy, Kankanala J; Shah, Jay D; Kale, Rohit V; Reddy, T Jayakrishna



Navigated cup implantation in hip arthroplasty  

PubMed Central

Background and purpose Many studies have suggested that navigation-based implantation can improve cup positioning in total hip arthroplasty (THA). We conducted a systematic review and meta-analysis to compile the best available evidence, and to overcome potential shortcomings because of small sample sizes in individual studies. Methods The search strategy covered the major medical databases from January 1976 through August 2007, as well as various publishers' databases. The internal validity of individual studies was evaluated independently by 3 reviewers. We used random-effects modeling to obtain mean differences in cup angulation and relative risk (RR) of cup positioning outside Lewinnek's safe zone. Results Of 363 citations originally identified, 5 trials of moderate methodology enrolling a total of 400 patients were included in the analysis. Mean cup inclination and anteversion were not statistically significantly different between the conventional groups and the navigated groups. Navigation reduced the variability in cup positioning and the risk of placing the acetabular component beyond the safe zone (RR = 0.21, CI: 0.13–0.32). Interpretation Based on the current literature, navigation is a reliable tool to optimize cup placement, and to minimize outliers. However, long-term outcomes and cost utility analyses are needed before conclusive statements can be drawn about the value of routine navigation in THA.



Acetabular blood flow during total hip arthroplasty  

PubMed Central

Objective To determine the immediate effect of reaming and insertion of the acetabular component with and without cement on periacetabular blood flow during primary total hip arthroplasty (THA). Design A clinical experimental study. Setting A tertiary referral and teaching hospital in Toronto. Patients Sixteen patients (9 men, 7 women) ranging in age from 30 to 78 years and suffering from arthritis. Intervention Elective primary THA with a cemented (8 patients) and noncemented (8 patients) acetabular component. All procedures were done by a single surgeon who used a posterior approach. Main outcome measure Acetabular bone blood-flow measurements made with a laser Doppler flowmeter before reaming, after reaming and after insertion of the acetabular prosthesis. Results Acetabular blood flow after prosthesis insertion was decreased by 52% in the noncemented group (p < 0.001) and 59% in the cemented group (p < 0.001) compared with baseline (prereaming) values. Conclusion The significance of these changes in periacetabular bone blood flow during THA may relate to the extent of bony ingrowth, periprosthetic remodelling and ultimately the incidence of implant failure because of aseptic loosening.

ElMaraghy, Amr W.; Schemitsch, Emil H.; Waddell, James P.



Can technology improve alignment during knee arthroplasty.  


Component malalignment remains a concern in total knee arthroplasty (TKA); therefore, a series of technologies have been developed to improve alignment. The authors conducted a systematic review to compare computer-assisted navigation with conventional instrumentation, and assess the current evidence for patient-matched instrumentation and robot-assisted implantation. An extensive search of the PubMed database for relevant meta-analyses, systematic reviews and original articles was performed, with each study scrutinised by two reviewers. Data on study characteristics and outcomes were extracted from each study and compared. In total 30 studies were included: 10 meta-analyses comparing computer-assisted navigation and conventional instrumentation, 13 studies examining patient-matched instrumentation, and seven investigating robot-assisted implantation. Computerassisted navigation showed significant and reproducible improvements in mechanical alignment over conventional instrumentation. Patient-matched instrumentation appeared to achieve a high degree of mechanical alignment, although the majority of studies were of poor quality. The data for robot-assisted surgery was less indicative. Computer-assisted navigation improves alignment during TKA over conventional instrumentation. For patient-matched instrumentation and robot-assisted implantation, alignment benefits have not been reliably demonstrated. For all three technologies, clinical benefits cannot currently be assumed, and further studies are required. Although current technologies to improve alignment during TKA appear to result in intra-operative benefits, their clinical impact remains unclear, and surgeons should take this into account when considering their adoption. PMID:24034591

Thienpont, Emmanuel; Fennema, Peter; Price, Andrew



Wound necrosis after total knee arthroplasty.  


Quickly evolutive skin necrosis and deep infection after total knee arthroplasty (TKA) are not uncommon. Several predisposing factors, such as immunosuppression, malnutrition, steroid use, rheumatoid arthritis, multiple scars, and vascular disease can be involved in the onset of wound complications, as well as long tourniquet time and early knee flexion. Skin necrosis after TKA can be treated in different ways, including local wound care, debridement, and soft tissue coverage with muscle or skin grafts. This article presents a rare case of skin necrosis occurring in a patient without any other apparent risk factor after TKA. A 78-year-old woman affected by primary osteoarthritis of the right knee who had no comorbidities and who had already undergone TKA for primary osteoarthritis on the left knee underwent a cemented TKA. Three days postoperatively, she developed a fever and wound problems, which soon after turned into skin necrosis. This complication was first treated surgically with a debridement of the wound with antibiotic therapy and local wound care, then with vacuum-assisted closure (Kinetic Concepts Inc, San Antonio, Texas) therapy and soft tissue coverage using skin grafting. She had a complete recovery in the next 3 months; the skin grafting was well tolerated and the range of motion and functional outcome were good. PMID:19292412

Patella, Vittorio; Speciale, Domenico; Patella, Silvio; Moretti, Biagio; Pesce, Vito; Spinarelli, Antonio



Liner exchange in total knee arthroplasty.  


Exchange of the tibial liner in revision knee arthroplasty for wear and other indications is controversial. The purpose of the study was to determine the clinical success and reoperation rate for liner exchange performed for four groups of patients. Thirty-nine revisions were identified in which modular liner exchange was performed: polyethylene wear (12 knees), acute infection (11 knees), instability (4 knees), and a variety of other diagnoses (12 knees). The knees were evaluated using the systems of the Knee Society. The mean follow-up time was 4.3 years. Liner exchange for wear was successful in all 12 patients: for acute infection, in 9 of 11 patients; for instability, in 3 of 4 patients; for other diagnoses, in 10 of 12 patients. There were significant improvements in the pain score in all four groups and significant improvement in the function score in the infection and other diagnoses groups. With the use of six criteria, these observations suggest that liner exchange for wear is successful. PMID:23628569

Lachiewicz, Paul F; Soileau, Elizabeth S



Metal-on-Metal Total Hip Resurfacing Arthroplasty  

PubMed Central

Executive Summary Objective The objective of this review was to assess the safety and effectiveness of metal on metal (MOM) hip resurfacing arthroplasty for young patients compared with that of total hip replacement (THR) in the same population. Clinical Need Total hip replacement has proved to be very effective for late middle-aged and elderly patients with severe degenerative diseases of the hips. As indications for THR began to include younger patients and those with a more active life style, the longevity of the implant became a concern. Evidence suggests that these patients experience relatively higher rates of early implant failure and the need for revision. The Swedish hip registry, for example, has demonstrated a survival rate in excess of 80% at 20 years for those aged over 65 years, whereas this figure was 33% by 16 years in those aged under 55 years. Hip resurfacing arthroplasty is a bone-conserving alternative to THR that restores normal joint biomechanics and load transfer. The technique has been used around the world for more than 10 years, specifically in the United Kingdom and other European countries. The Technology Metal-on-metal hip resurfacing arthroplasty is an alternative procedure to conventional THR in younger patients. Hip resurfacing arthroplasty is less invasive than THR and addresses the problem of preserving femoral bone stock at the initial operation. This means that future hip revisions are possible with THR if the initial MOM arthroplasty becomes less effective with time in these younger patients. The procedure involves the removal and replacement of the surface of the femoral head with a hollow metal hemisphere, which fits into a metal acetabular cup. Hip resurfacing arthroplasty is a technically more demanding procedure than is conventional THR. In hip resurfacing, the femoral head is retained, which makes it much more difficult to access the acetabular cup. However, hip resurfacing arthroplasty has several advantages over a conventional THR with a small (28 mm) ball. First, the large femoral head reduces the chance of dislocation, so that rates of dislocation are less than those with conventional THR. Second, the range of motion with hip resurfacing arthroplasty is higher than that achieved with conventional THR. A variety of MOM hip resurfacing implants are used in clinical practice. Six MOM hip resurfacing implants have been issued licences in Canada. Review Strategy A search of electronic bibliographies (OVID Medline, Medline In-Process and Other Non-Indexed Citations, Embase, Cochrane CENTRAL and DSR, INAHTA) was undertaken to identify evidence published from Jan 1, 1997 to October 27, 2005. The search was limited to English-language articles and human studies. The literature search yielded 245 citations. Of these, 11 met inclusion criteria (9 for effectiveness, 2 for safety). The result of the only reported randomized controlled trial on MOM hip resurfacing arthroplasty could not be included in this assessment, because it used a cemented acetabular component, whereas in the new generation of implants, a cementless acetabular component is used. After omitting this publication, only case series remained. Summary of Findings   Health Outcomes The Harris hip score and SF-12 are 2 measures commonly used to report health outcomes in MOM hip resurfacing arthroplasty studies. Other scales used are the Oxford hip score and the University of California Los Angeles hip score. The case series showed that the mean revision rate of MOM hip resurfacing arthroplasty is 1.5% and the incidence of femoral neck fracture is 0.67%. Across all studies, 2 cases of osteonecrosis were reported. Four studies reported improvement in Harris hip scores. However, only 1 study reported a statistically significant improvement. Three studies reported improvement in SF-12 scores, of which 2 reported a significant improvement. One study reported significant improvement in UCLA hip score. Two studies reported postoperative Oxford hip scores, but no preoperative values were reported. None of the reviewed studies r



GAP Analysis. Bulletin Number 11.  

National Technical Information Service (NTIS)

The 2002 issue of the Gap Analysis Bulletin is the eleventh in a series of annual publications produced by the National Gap - -- Analysis Program. Gap Analysis Bulletin No. 11 features 18 articles on various aspects of gap analysis methods and results. Th...

E. S. Brackney R. Brannon K. J. Gergely M. D. Jennings



Tunable photonic band gap fiber  

Microsoft Academic Search

The ability to change the photonic band gap structure continuously and reversibly by modifying the index thermally allows the band gap features to be sensitively tuned, allowing for a thorough investigation of the various band gap guiding properties. Furthermore, it may be possible to use this type of band gap fiber as a tunable filter. Investigations of the dispersion properties

R. T. Bise; R. S. Windeler; K. S. Kranz; C. Kerbage; B. J. Eggleton; D. J. Trevor





A multiple spark gap switch of unique construction is described which will permit controlled, simultaneous discharge of several capacitors into a load. The switch construction includes a disc electrode with a plurality of protuberances of generally convex shape on one surface. A firing electrode is insulatingly supponted In each of the electrode protuberances and extends substantially to the apex thereof. Individual electrodes are disposed on an insulating plate parallel with the disc electrode to form a number of spark gaps with the protuberances. These electrodes are each connected to a separate charged capacitor and when a voltage ls applied simultaneously between the trigger electrodes and the dlsc electrode, each spark gap fires to connect its capacitor to the disc electrode and a subsequent load.

Schofield, A.E.



Bridging a cultural gap  

NASA Astrophysics Data System (ADS)

There has been a broad wave of change in tertiary calculus courses in the past decade. However, the much-needed change in tertiary pre-calculus programmes—aimed at bridging the gap between high-school mathematics and tertiary mathematics—is happening at a far slower pace. Following a discussion on the nature of the gap and the objectives of a potential bridging programme, this paper aims at demonstrating that the gap can be bridged, by presenting an ongoing modular bridging programme especially designed for the diverse types of student populations in teachers training colleges. We also present here some innovative teaching and assessment methods that were judged essential for the success of these programmes—focusing mainly on the "Questionnaire Based Instruction Method". Finally we suggest directions of follow up and research.

Leviatan, Talma



Closing the Health Gap  

NSDL National Science Digital Library

The US Department of Health and Human Services (HHS) and ABC Radio Networks are working together to help African-Americans gain access to the best possible information regarding health issues. HHS reports that life expectancies for African-Americans lag five years behind expectancies for White Americans. The new Website Closing the Health Gap has links to information on health conditions such as diabetes and cancer as well as consumer health resources that relate to African-Americans' particular needs. Each page offers links, publications, and any news related to the subject, all in an effort to close "the health gap."



Spark gap electrode erosion  

NASA Astrophysics Data System (ADS)

The results of a one-year contract on electrode erosion phenomena are summarized. The arc voltage drop in a spark gap was measured for various electrode, gas, and pressure combinations. A previously developed model of self breakdown voltage distribution was extended. A jet model for electrode erosion was proposed and an experimental arrangement for testing the model was constructed. The effects of inhomogeneities and impurities in the electrodes were investigated. Some of the work described here is scheduled for completion in 1985 under a current grant (AFOSR 84-0032). The areas of investigation described here include: (1) Self breakdown voltage distributions; (2) Electrode erosion; (3) Spark gap voltage recovery.

Krompholz, H.; Kristiansen, M.



Long-term results of the GSB III elbow arthroplasty  

Microsoft Academic Search

since more young patients undergo joint replacement and revision surgery, particularly with the exchange of a pros- thesis, has many technical problems with a reduced pros- pect of success. Replacement arthroplasty of the elbow is not a common operation. The number has increased in the last ten years, and the results are improving, but the percentage of compli- cations and

N. Gschwend; N. H. Scheier; A. R. Baehler



The importance of femoral intramedullary entry point in knee arthroplasty  

Microsoft Academic Search

The purpose of this cadaveric study was to investigate how alignment of the femoral component in knee arthroplasty may be influenced by the entry site of the femoral intramedullary alignment rod. The angle between the rod and the distal femoral articular surface was measured in 20 non-arthritic cadaveric femurs using three different entry points. Entry points 10 mm anterior to

I. J Harding; R. W Crawford; P Mclardy-Smith; D. W Murray



Periprosthetic fractures of the femur after total knee arthroplasty  

PubMed Central

Periprosthetic fracture following total knee arthroplasty is a potentially serious complication. This injury can involve the distal femur, proximal tibia or the patella. This review article analyzes the prevalence, risk factors, classification and treatment options for periprosthetic fractures of the femur.

McGraw, Phil



Influence of surface finish in total hip arthroplasty  

Microsoft Academic Search

The influence of femoral component surface finish was investigated by comparing 2 finishes, precoat and satin finish, for 1 cemented total hip arthroplasty (THA) system using 1 acetabular cup design. All surgeries were performed by a single surgeon in 2 consecutive series. Minimum 2-year follow-up outcomes (36 precoat, 25 satin) were compared using Harris Hip Scores, radiographs, and survivorships. The

Bradley K Vaughn; Elizabeth Fuller; Rebekah Peterson; Susan G Capps



Total knee arthroplasty in the management proximal tibial stress fractures  

Microsoft Academic Search

Five patients with stress fractures of the proximal tibia adjacent to an arthritic knee joint were treated by resurfacing arthroplasty with intramedullary fixation of the fracture. All five fractures healed and limb realignment was achieved. The literature concerning proximal tibial stress structures in relation to the arthritic knee and the management of this condition is reviewed.

M. P. W. Tomlinson; I. M. Dingwall; H. Phillips



Minimally invasive hip arthroplasty: a quantitative review of the literature  

Microsoft Academic Search

Purpose: To perform a comprehensive quantitative review of the published literature and to assess the methodology of studies comparing the surgical outcomes in minimally invasive hip arthroplasty (MIHA). Methods: We conducted a comprehensive literature search using Medline, Embase, Cochrane, CINAHL and Google Scholar. The bibliographies of papers were also examined. All relevant articles in peer-reviewed journals were retrieved except those

Ansar Mahmood; Mohammed S. Zafar; Ibrar Majid; Nicola Maffulli; John Thompson


Infection rate following total joint arthroplasty in the HIV population.  


The purpose of this study is to review a large series of HIV-infected patients who underwent total joint arthroplasty and identify potential risk-factors for infection. Sixty-nine HIV-infected arthroplasty cases were analyzed with 138 matched controls. Deep infection rate following total hip or knee arthroplasty was 4.4% (3 of 69) among HIV cases compared to 0.72% (1 of 138) among controls, yielding a non-significant 6.22 times increased odds of infection (95% CI 0.64-61.0, P=0.11). Kaplan-Meier survival curves for infection free survival and revision free survival revealed non-significantly decreased survival in HIV cases compared to controls (P=0.06 and P=0.09). Our results suggest that the rate of early joint infection following primary total joint arthroplasty in the HIV-infected population is lower than reported in a number of previously published studies. PMID:23523495

Capogna, Brian M; Lovy, Andrew; Blum, Yossef; Kim, Sun Jin; Felsen, Uriel R; Geller, David S




Microsoft Academic Search

e reviewed 194 revision arthroplasties of the hip and knee performed over a ten-year period. The results of intraoperative Gram staining were available in 169 (87%). Thirty-two were found to be infected (11 hips and 21 knees) and 137 had no evidence of infection. Intraoperative Gram staining was negative in all 169 cases. The method therefore had a sensitivity of



Synovectomy, debridement, and continuous irrigation for infected total knee arthroplasty  

Microsoft Academic Search

Since 1990, a total of ten joints in nine patients with infected total knee arthroplasty have been treated in our department within 21 days of the onset of infection. Their radiographs showed no evidence of implant loosening or “moth-eaten” appearance. They underwent synovectomy, debridement, and continuous irrigation without implant removal. Continuous irrigation was maintained for 7–29 days. It was possible

Hiroshi Tsumura; Shinichi Ikeda; Takashi Ono; Ichiro Itonaga; Hirofumi Taira; Takehiko Torisu



Gender-Specific Design in Total Knee Arthroplasty  

Microsoft Academic Search

Total knee arthroplasty (TKA) has now been performed for more than 3decades, with millions of implantations, and a tremendous volume of scientific data regarding its use. There is little, if anything, in the academic literature to suggest an inferior result when a TKA is performed in a female patient. Recently, implant manufacturers have introduced TKA designs with modified dimensions to

Kenneth A. Greene



Reducing metal ion release following hip resurfacing arthroplasty.  


Recent guidelines have suggested that routine postoperative care of patients with metal-on-metal hip prostheses should involve metal ion analysis. This study sought to investigate the relationship between bearing surface wear rates of metal components and serum metal ion analysis and also to quantify the incidence of excessive increases in serum metal ion concentrations post-hip resurfacing arthroplasty. PMID:21435493

Langton, David J; Joyce, Thomas J; Mangat, Navjeet; Lord, James; Van Orsouw, Maarten; De Smet, Koen; Nargol, Antoni V F



Paratibial cyst associated with wear debris after total knee arthroplasty  

Microsoft Academic Search

We present a case in which a synovial cyst arose from the proximal tibia and expanded in the calf of a patient after total knee arthroplasty. A cystogram showed a direct communication between the joint cavity and the cyst, apparently associated with a screw that penetrated the tibial cortex. Histologic examination of the cyst showed an inflammatory reaction, including macrophages,

Toshihiro Akisue; Masahiro Kurosaka; Nobuzo Matsui; Motoi Yamaguchi; Kei-ichiro Hasuda; Thomas W. Bauer; Shin-ichi Yoshiya



Case report: Salmonella infection following total hip arthroplasty.  


A case of a total hip arthroplasty infection with Staphylococcus aureus, co-infected with Salmonella choleraesuis was treated with two-stage exchange and administration of vancomycin and ciprofloxacin. No signs of re-infection have appeared fourteen months after surgery. Cases of salmonella infection of hip prostheses are quite rare, with only a handful of reports in the literature. PMID:16089070

Chong, Paul Y; Sporer, Scott M



Prevention of Venous Thromboembolism After Hip or Knee Arthroplasty  

Microsoft Academic Search

A survey was mailed to a representative sample of US orthopedic surgeons to assess protocols for the prevention of venous thromboembolism after lower extremity total joint arthroplasty. Practices were examined by type of operation, annual surgical volume, and opinions of consensus guidelines issued by the American Academy of Orthopaedic Surgeons and the American College of Chest Physicians. Although there was

Frederick A. Anderson; Wei Huang; Richard J. Friedman; Louis M. Kwong; Jay R. Lieberman; Vincent D. Pellegrini


Rollback in posterior cruciate ligament—retaining total knee arthroplasty  

Microsoft Academic Search

A clinical and radiographic study of 49 posterior cruciate ligament—retaining total knee arthroplasties in 38 patients (11 bilateral, 27 unilateral), using prostheses of the same design, was undertaken to quantify the amount of in vivo rollback (ie, the anteroposterior translation of the tibia with respect to the femur during flexion). The mean difference in the distances between the contact points

Henry Kim; Richard R. Pelker; David H. Gibson; John F. Irving; J. Kevin Lynch



A Review of Distal Ulnar Hemi-Resection Arthroplasty  

Microsoft Academic Search

15 patients with pain and disability on the ulnar side of the wrist were treated by distal ulnar hemiresection arthroplasty. The patients’ diagnoses fell into three groups, namely ulnocarpal impingement, primary osteoarthritis of the distal radio-ulnar joint and traumatic disruption of the distal radioulnar joint. Patients were assessed pre- and post-operatively on the basis of pain and forearm rotation. Grip




Magnitude of Limb Lengthening After Primary Total Knee Arthroplasty  

Microsoft Academic Search

Patients will often perceive a change in lower limb length after total knee arthroplasty (TKA). From this observed finding, we asked how frequently does a change in limb length occur after TKA. Preoperative and postoperative full-length standing radiographs were obtained for 102 knees in 98 patients who underwent TKA. Digital radiography software was used to measure the mechanical axis and

Jason E. Lang; Richard D. Scott; Jess H. Lonner; James V. Bono; David J. Hunter; Ling Li


Ipsilateral Patellofemoral Arthroplasty and Autogenous Osteochondral Femoral Condylar Transplantation  

Microsoft Academic Search

The aim of this study was to report the results of ipsilateral patellofemoral arthroplasty and autologous osteochondral transplantation for patellofemoral arthritis and focal full-thickness chondral defects of the femoral condyles. The size of the condylar cartilage defects ranged from as small as 10 × 9 mm to as big as 24 × 7 mm. The mean Knee Society function score

Jess H. Lonner; Samir Mehta; Robert E. Booth



Metal sensitivity in patients with joint replacement arthroplasties.  

PubMed Central

A high incidence of unexpected metal sensitivity was found in patients with metal-to-metal (McKee) hip arthroplasties. Patients with metal-to-plastic (Charnley) prostheses had no greater incidence of metal sensitivity than a control group awaiting operation. If metal sensitivity does occur loosening of the prosthesis may be a complication.

Benson, M K; Goodwin, P G; Brostoff, J



Sporting and physical activity following Oxford medial unicompartmental knee arthroplasty  

Microsoft Academic Search

The purpose of this study was to evaluate and assess the sporting and physical activities of patients who had undergone an Oxford medial unicompartmental knee arthroplasty (UKA). Seventy-six patients who underwent a UKA between 2000 and 2003 were reviewed. Demographic data such as age, sex and comorbidities were recorded. University of California Los Angeles (UCLA) activity level ratings and Oxford

N. Fisher; M. Agarwal; S. F. Reuben; D. S. Johnson; P. G. Turner



Pathophysiology of surgical site infection in total hip arthroplasty  

Microsoft Academic Search

This article is a case report of a 69-year-old man who underwent a right total hip replacement procedure and developed a surgical site infection. Areas of concern in prevention and treatment of hip arthroplasty infection are presented, focusing on the pathophysiologic process involved. A review of the patient risk factors and the pathophysiologic action potentiating risk for infection include host

Dorothy J. Seibert



Exeter total hip arthroplasty with matte or polished stems  

Microsoft Academic Search

Summary. Objective. To compare implant survival rates after total hip arthroplasty with Exeter matte or polished stems and to determine the relationship of synovitis\\/joint effusion to signs of implant loosening and stem type. Material and methods. The first part of the study included retrospective revision rate analysis of 118 primary hip replacements performed during 1991-1995. Two different designs of Exeter

Alfredas Smailys; Uldis Kesteris; Romas Jonas Kalesinskas; Hans Wingstrand


Two-stage Reimplantation of Infected Hip Arthroplasties  

Microsoft Academic Search

Background: Although two-stage reimplantation for infected hip arthroplasty has a high success rate, the protocols of the antibiotic therapy after resection arthroplas- ty have varied in different reports. The purpose of this study was to evaluate the clinical outcomes of two-stage reimplantation for infected hip arthroplas- ty using our protocol of combined parenteral and oral antibiotic therapy and the criterion

Wun-Schen Chen; Te-Hu Fu; Jun-Wen Wang


Stress analysis of cemented glenoid prostheses in Total Shoulder Arthroplasty  

Microsoft Academic Search

Glenoid component loosening is the most-frequently encountered problem in the total shoulder arthroplasty. The purpose of the study was to investigate whether failure of the glenoid component is caused by stresses generated within the cement mantle, implant materials and at the various interfaces during humeral abduction, using 3-D FE analyses of implanted glenoid structures. FE models, one total polyethylene and

S. Gupta; F. van Keulen



Gaining on the Gap  

ERIC Educational Resources Information Center

|About three-quarters of the 2009 graduates of the highly diverse Arlington, Virginia, Public Schools completed one or more Advanced Placement or International Baccalaureate courses during their high school careers. That figure serves as one indicator of a decade-long initiative to eliminate achievement gaps while raising achievement for all…

Smith, Robert G.



Confronting the Autonomy Gap  

ERIC Educational Resources Information Center

|"The Autonomy Gap," a recent study by the American Institute for Research and the Thomas B. Fordham Institute, found that many public elementary school principals feel constrained by a bureaucracy that impedes their ability to raise student achievement. Unfortunately, those principals are still held accountable for their school's results--even…

Adamowski, Steven; Petrilli, Michael J.



Multiple gap photovoltaic device  


A multiple gap photovoltaic device having a transparent electrical contact adjacent a first cell which in turn is adjacent a second cell on an opaque electrical contact, includes utilizing an amorphous semiconductor as the first cell and a crystalline semiconductor as the second cell.

Dalal, Vikram L. (Newark, DE)



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



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



The Teaching Gap  

ERIC Educational Resources Information Center

One of the most comprehensive studies to highlight the achievement gap between students in the United States and those in many other countries is the Third International Mathematics and Science Study (TIMSS). TIMSS showed that a handful of countries (with Japan near the top) consistently outperformed the others studied (including the United…

Feldman, Sandra



Computer-Assisted Hip and Knee Arthroplasty. Navigation and Active Robotic Systems  

PubMed Central

Executive Summary Objective The Medical Advisory Secretariat undertook a review of the evidence on the effectiveness and cost-effectiveness of computer assisted hip and knee arthroplasty. The two computer assisted arthroplasty systems that are the topics of this review are (1) navigation and (2) robotic-assisted hip and knee arthroplasty. The Technology Computer-assisted arthroplasty consists of navigation and robotic systems. Surgical navigation is a visualization system that provides positional information about surgical tools or implants relative to a target bone on a computer display. Most of the navigation-assisted arthroplasty devices that are the subject of this review are licensed by Health Canada. Robotic systems are active robots that mill bone according to information from a computer-assisted navigation system. The robotic-assisted arthroplasty devices that are the subject of this review are not currently licensed by Health Canada. Review Strategy The Cochrane and International Network of Agencies for Health Technology Assessment databases did not identify any health technology assessments on navigation or robotic-assisted hip or knee arthroplasty. The MEDLINE and EMBASE databases were searched for articles published between January 1, 1996 and November 30, 2003. This search produced 367 studies, of which 9 met the inclusion criteria. Summary of Findings Navigation-Assisted Arthroplasty Five studies were identified that examined navigation-assisted arthroplasty. A Level 1 evidence study from Germany found a statistically significant difference in alignment and angular deviation between navigation-assisted and free-hand total knee arthroplasty in favour of navigation-assisted surgery. However, the endpoints in this study were short-term. To date, the long-term effects (need for revision, implant longevity, pain, functional performance) are unknown.(1) A Level 2 evidence short-term study found that navigation-assisted total knee arthroplasty was significantly better than a non-navigated procedure for one of five postoperative measured angles.(2) A Level 2 evidence short-term study found no statistically significant difference in the variation of the abduction angle between navigation-assisted and conventional total hip arthroplasty.(3) Level 3 evidence observational studies of navigation-assisted total knee arthroplasty and unicompartmental knee arthroplasty have been conducted. Two studies reported that “the follow-up of the navigated prostheses is currently too short to know if clinical outcome or survival rates are improved. Longer follow-up is required to determine the respective advantages and disadvantages of both techniques.”(4;5) Robotic-Assisted Arthroplasty Four studies were identified that examined robotic-assisted arthroplasty. A Level 1 evidence study revealed that there was no statistically significant difference between functional hip scores at 24 months post implantation between patients who underwent robotic-assisted primary hip arthroplasty and those that were treated with manual implantation.(6) Robotic-assisted arthroplasty had advantages in terms of preoperative planning and the accuracy of the intraoperative procedure.(6) Patients who underwent robotic-assisted hip arthroplasty had a higher dislocation rate and more revisions.(6) Robotic-assisted arthroplasty may prove effective with certain prostheses (e.g., anatomic) because their use may result in less muscle detachment.(6) An observational study (Level 3 evidence) found that the incidence of severe embolic events during hip relocation was lower with robotic arthroplasty than with manual surgery.(7) An observational study (Level 3 evidence) found that there was no significant difference in gait analyses of patients who underwent robotic-assisted total hip arthroplasty using robotic surgery compared to patients who were treated with conventional cementless total hip arthroplasty.(8) An observational study (Level 3 evidence) compared outcomes of total knee arthroplasty between patients undergoing robotic surgery and patients



Total knee arthroplasty: Limb length discrepancy and functional outcome  

PubMed Central

Background: Limb length discrepancy and its effects on patient function have been discussed in depth in the literature with respect to hip arthroplasty but there are few studies that have examined the effect on function of limb length discrepency following total knee arthroplasty (TKA). The aim of this study was to determine whether limb length discrepancy after TKA in patients with bilateral osteoarthritis of knee with varus deformity affects functional outcome. Materials and Methods: Fifty-four patients with bilateral osteoarthritis of knee with varus deformity, who were operated for total knee arthroplasty from 1996 to 2008, were reviewed retrospectively. The patients were divided into two groups. Thirty patients (mean age 64 years) were operated for unilateral TKA and thirty patients (mean age 65.8 years) were operated for bilateral total knee arthroplasty. Six patients underwent staged surgery and were included in both groups as the time interval between the two surgeries was more than the minimum 6-month follow-up period specified for inclusion in the study. The limb length discrepancy was measured and statistically correlated with the functional component of the Knee Society Score. Result: In the unilateral group (n=30), the mean limb length discrepancy was 1.53 cm (range: 0-3 cm) and the mean functional score was 73 (range: 45-100). In the bilateral group (n=30), the mean limb length discrepancy was 0.5 cm (range: 0-2 cm) and the mean functional score was 80.67 (range: 0-100). A statistically significant negative correlation was found between limb length discrepancy and functional score in the unilateral group (Spearman correlation coefficient, r =?0.52, P=0.006), while no statistically significant correlation was found in the bilateral group (Spearman correlation coefficient, r = ?0.141, P=0.458). Conclusion: Limb length discrepancy affects functional outcome after total knee arthroplasty, especially so in patients of bilateral osteoarthritis with varus deformity undergoing surgery of only one knee.

Vaidya, Shrinand V; Patel, Mihir R; Panghate, Atul N; Rathod, Parthiv A



Gait and Stair Function in Total and Resurfacing Hip Arthroplasty: A Pilot Study  

Microsoft Academic Search

Standard total hip arthroplasty (THA) is the established surgical treatment for patients older than 65 years with progressive\\u000a osteoarthritis but survivorship curves wane in patients younger than 50. Resurfacing hip arthroplasty (RHA) is an alternative\\u000a for younger, active patients reportedly providing superior range of motion. Quantitative investigation of functional recovery\\u000a following arthroplasty may elucidate limitations that aid in device selection. Although

M. Wade Shrader; Manoshi Bhowmik-Stoker; Marc C. Jacofsky; David J. Jacofsky



The computer-assisted sequential lateral soft-tissue release in total knee arthroplasty for valgus knees  

PubMed Central

Soft-tissue management is a critical factor in total knee arthroplasty, especially in valgus knees. The stepwise release has been based upon surgeon’s experience. Computer-assisted surgery has gained increasing scientific interest in recent times and allows the intraoperative measurement of leg axis and gap size in extension and flexion. We therefore aimed to analyse the effect of sequential lateral soft-tissue release and the resulting change in the a.p. limb axis on the one hand and the tibiofemoral gaps on the other hand in extension as well as in flexion in eight cadaveric knees. Measurements were obtained using a CT-free navigation system. In extension the highest increase compared to the previous release step was found for the first (iliotibial band, P?=?0.002), second (popliteus muscle, P?=?0.0003), third (LCL, 0.007) and the sixth (entire PCL, P?=?0.001) release step. In 90° flexion all differences of the lateral release steps were statistically significant (P?gap in flexion was found after the second (popliteus muscle, P?=?0.004) and third (LCL, 0.007) release step. Computer-assisted surgery allows measurement of the effect of each release step of the sequential lateral release sequence and helps the surgeon to better assess the result.

Oczipka, F.; Grifka, J.; Perlick, L.



Stabilizers for GAP and GAP-based Propellants Interim Report.  

National Technical Information Service (NTIS)

Stabilizers for Glycidyl Azide Polymer (GAP) and GAP-based propellants were evaluated by Atlantic Research Corporation (ARC) and 3M (subcontract). The objectives of the program were: 1. to determine the stability of GAP; 2. to document the effect of prope...

B. Wheatley E. Nieder



The malaria gap.  


Although the correlation between malaria and poverty is apparent, the nature of the linkages in terms of directions and mechanisms of causation is less so, and different methodologic approaches provide widely divergent perspectives concerning the impact of the disease. Certain macroeconomic studies find that in highly endemic countries, malaria may be responsible for reducing economic growth by more than one percentage point a year. Microeconomic studies, which aggregate the cost per case, find a considerably smaller impact, generally less than one percent of annual per capita gross domestic product. The large gap between these estimates suggests economic externalities associated with malaria that make the burden much greater than the sum of the costs of individual cases. Both the magnitude of the burden and the channels through which malaria affects reduces income are important for policymakers. We explore this gap, examining diverse mechanisms through which malaria can affect long-term economic development. PMID:15331830

Malaney, Pia; Spielman, Andrew; Sachs, Jeffrey



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



Air-gap heterostructures  

SciTech Connect

We demonstrate the fabrication of thin GaAs layers which quasi hover above the underlying GaAs substrate. The hovering layers have a perfect epitaxial relationship to the substrate crystal lattice and are connected to the substrate surface only by lattice matched nanopillars of low density. These air-gap heterostructures are created by combining in situ molecular beam epitaxy compatible self-assembled droplet-etching and ex situ selective wet-chemical etching.

Heyn, Ch.; Schmidt, M.; Schwaiger, S.; Stemmann, A.; Mendach, S.; Hansen, W. [Institut fuer Angewandte Physik und Zentrum fuer Mikrostrukturforschung, Jungiusstrasse 11, D-20355 Hamburg (Germany)



Bridging the gap  

Microsoft Academic Search

Engineers are applying the results of the scientific method to achieving solutions for real world problems. The QFT robust\\u000a design technique was utilized in this paper to illustrate how the bridging of the gap between the scientific and engineering\\u000a methods can be achieved. As an example, an aerospace firm has stated to Professor M. Grimble, University of Strathcldye, the\\u000a following:

C. Houpis


[Treatment of glottal gap].  


Glottal gaps can be either physiological or pathological. The latter are multifactorial, predominantly organic in origin and occasionally functional. Organic causes include vocal fold paralysis or scarring, as well as a deficiency or excess of tissue. In addition to loss of the mucosal wave, the degree of hoarseness is primarily determined by the circumferential area of the glottal gap. It is thus important to quantify the extent of glottal insufficiency. Although a patient's symptoms form the basis for treatment decisions, these may be subjective and inadequately reflected by the results of auditory-perceptual evaluation, voice analysis and voice performance tests. The therapeutic approach should always combine phonosurgery with conventional voice therapy methods. Voice therapy utilises all the resources made available by the sphincter model of the aerodigestive tract and knowledge on the mechanism of voice production. The aim of phonosurgery is medialization, reconstruction or reinnervation by injection laryngoplasty or larynx framework surgery. These different methods can be combined and often applied directly after vocal fold surgery (primary reconstruction). In conclusion, the techniques described here can be effectively employed to compensate for glottal gaps. PMID:23407775

Voigt-Zimmermann, S; Arens, C



Investigations of Pulsed Vacuum Gap.  

National Technical Information Service (NTIS)

Past research and the current status of understanding of electrical breakdown of vacuum is reviewed. This review includes DC, AC and pulsed vacuum gap breakdown. Measurements have been performed to determine the role of microparticles in pulsed vacuum gap...

J. E. Thompson T. S. Sudarshan J. M. Butner



Nanosecond Spark Gap Switching Measurements.  

National Technical Information Service (NTIS)

The switching time of gas and oil dielectric spark gaps was measured in the nanosecond and subnanosecond time regime. The observed switching characteristics of the two spark gaps were compared with those predicted by empirical formulas. The formulas used ...

J. W. Ginn D. N. Hendricks M. T. Buttram



Dynamics of coupled gap solitons  

SciTech Connect

We show analytically that solitonic states of two modes associated with different gap edges are formed when incident waves are sent in layered dielectric systems with a small band gap. The resulting coupled gap solitons are described through a nonlinear Schr{umlt o}dinger equation and propagate with a speed equal to half the speed of light. We discuss the conditions for the existence of coupled gap solitons. {copyright} {ital 1996 The American Physical Society.}

Konotop, V.V. [Departamento de Fisica, Universidade da Madeira, Praca do Municipio, 9000 Funchal (Portugal); Tsironis, G.P. [Center for Nonlinear Studies, MS 258, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)



The predictive value of indium-III leukocyte scans in the diagnosis of infected total hip, knee, or resection arthroplasties  

Microsoft Academic Search

To evaluate the usefulness of the indium-1 1 1 scan in detecting actually or potentially infected total hip, knee, and resection arthroplasties, 153 scans were performed on 143 patients who underwent reoperation for a loose or painful total joint arthroplasty or a resection arthroplasty between 1990 and 1996. Scans were interpreted as infected, not infected, or equivocal by an experienced

David M. Scher; Kevin Pak; Jess H. Lonner; Jo Ellen Finkel; Joseph D. Zuckerman; Paul E. Di Cesare



Gapping, Pseudogapping and Sideward Movement  

Microsoft Academic Search

English Pseudogapping constructions share some surface similarities with both Gapping and Verb Phrase Ellipsis (VPE). Levin (1978, 1979 (main text)) concludes, however, that Pseudogapping is transformationally unrelated to both Gapping and VPE. We argue that this conclusion is only partially correct. Gapping and Pseudogapping are transformationally related in that they both involve the application of verb movement, in particular sideward

Brian Agbayani; Ed Zoerner



Antibiotic Loaded Bone Cement Reduces Deep Infection Rates For Primary Reverse Total Shoulder Arthroplasty. A Retrospective, Cohort Study of 501 Shoulders  

Microsoft Academic Search

BackgroundDeep infection following primary reverse total shoulder arthroplasty is a devastating event and has an increased incidence compared to anatomic total shoulder arthroplasty. Recent reports in the hip and knee arthroplasty literature suggest that antibiotic loaded bone cement may lower infection rates for primary arthroplasties. We conducted a retrospective cohort study to evaluate the effect of antibiotic loaded bone cement

Robert J. Nowinski; Robert J. Gillespie; Yousef Shishani; Brian Cohen; Gilles Walch; Reuben Gobezie


Constraint in total knee arthroplasty: when and what?  


Tibiofemoral instability is increasingly recognized as a common mode of failure in total knee arthroplasty. Despite this, there are few published guidelines concerning treatment options, component selection, and expected results. In the treatment of the unstable total knee arthroplasty, cruciate-retaining designs can be considered only in the presence of well-balanced ligaments, including the posterior cruciate ligament. More predictable results are obtained with the use of cruciate-substituting components, but they provide no varus-valgus stability and cannot compensate for severe flexion laxity. Varus-valgus constrained designs cannot provide long-term stability in cases of varus-valgus instability or severe flexion laxity. Such cases are most reliably treated with a linked implant. PMID:12730930

McAuley, James P; Engh, Gerard A



Accuracy of computer-navigated total hip arthroplasty.  


Proper acetabular cup orientation is essential in total hip arthroplasty. The purpose of this study was to evaluate the accuracy of a particular imageless computer navigation system in determining cup position. Thirty-nine computer-navigated total hip arthroplasty intraoperative measurements of cup abduction and anteversion were compared with those from follow-up radiographs. Sensitivity, specificity, accuracy, prevalence-adjusted positive value (PPV), and negative predictive value were calculated for both navigation and radiographs. Navigation measurements had high specificity and PPV when assessing cup abduction and anteversion (specificity >90%, PPV >94%). In contrast, the system was not very effective in detecting suboptimal cup position (sensitivity abduction, 50%; anteversion, 33%). Intraoperative navigation readings in the safe zone have high probability of indicating correct placement. However, confirmation of suboptimal cup position intraoperatively requires additional diagnostic methods. PMID:21908165

Snyder, Garrett M; Lozano Calderón, Santiago A; Lucas, Paul A; Russinoff, Scott



Salvage hip arthroplasty after failed fixation of proximal femur fractures.  


We reviewed 46 patients who underwent salvage hip arthroplasty (SHA) for revision of failed cannulated screws (CS), sliding hip screws (SHS), or intramedullary nails (IMN). The primary objective was to determine differences in operative difficulty. SHA after failed femoral neck fixation was associated with lower intra-operative demands than after failed peri-trochanteric fractures. Similarly, analysis by the index implant found that conversion arthroplasty after failed CSs was associated with lower intra-operative morbidity than failed SHSs or IMNs; differences between SHS and IMN were not as clear. Importantly, intra-operative data in cases of failed SHSs were similar regardless of the original fracture type, showing the device played a larger role than the fracture pattern. Complications and revision surgery rates were similar regardless of fracture type or fixation device. Our results suggest that operative demands and subsequent patient morbidity are more dependent on the index device than the fracture pattern during SHA. PMID:23489728

DeHaan, Alexander M; Groat, Tahnee; Priddy, Michael; Ellis, Thomas J; Duwelius, Paul J; Friess, Darin M; Mirza, Amer J



Modular hybrid total hip arthroplasty. Experimental study in dogs  

PubMed Central

Background This prospective experimental study evaluated the surgical procedure and results of modular hybrid total hip arthroplasty in dogs. Methods Ten skeletally mature healthy mongrel dogs with weights varying between 19 and 27 kg were used. Cemented modular femoral stems and uncemented porous-coated acetabular cups were employed. Clinical and radiographic evaluations were performed before surgery and at 30, 60, 90, 120, 180 and 360 days post-operation. Results Excellent weight bearing was noticed in the operated limb in seven dogs. Dislocation followed by loosening of the prosthesis was noticed in two dogs, which were therefore properly treated with a femoral head osteotomy. Femoral fracture occurred in one dog, which was promptly treated with full implant removal and femoral osteosynthesis. Conclusions The canine modular hybrid total hip arthroplasty provided excellent functionality of the operated limb.



Comparison of drain clamp after bilateral total knee arthroplasty.  


Suction drains provide an easy and feasible method for controlling hemorrhage after total knee arthroplasty. However, there has been no compromise regarding the optimum clamping time for these drains. We conducted a randomized clinical trial in 50 patients to compare 12-hour drain clamping and continuous drainage after total knee arthroplasty in terms of wound complications, blood loss, and articular arc of motion. To eliminate any other factor except duration of clamping, we chose to compare only knees belonging to a single patient and to restrict the study to those knees undergoing surgery due to osteoarthritis. From a total of 100 knees (50 patients) studied, the 12-hour-clamping method resulted in a significantly smaller amount of postoperative blood loss (p < 0.001). The passive ranges of motion and wound complications were not significantly different between the two groups. PMID:21446627

Madadi, Firooz; Mehrvarz, Amir Sarshekeh; Madadi, Firoozeh; Boreiri, Majid; Abachizadeh, Kambiz; Ershadi, Ali



Diagnosis and Management of Infected Total Knee Arthroplasty§  

PubMed Central

Infection following total knee arthroplasty can be difficult to diagnose and treat. Diagnosis is multifactorial and relies on the clinical picture, radiographs, bone scans, serologic tests, synovial fluid examination, intra-operative culture and histology. Newer techniques including ultrasonication and molecular diagnostic studies are playing an expanded role. Two-stage exchange arthroplasty with antibiotic cement and 4-6 weeks of intravenous antibiotic treatment remains the most successful intervention for infection eradication. There is no consensus on the optimum type of interval antibiotic cement spacer. There is a limited role for irrigation and debridement, direct one-stage exchange, chronic antibiotic suppression and salvage procedures like arthrodesis and amputation. We examine the literature on each of the diagnostic modalities and treatment options in brief and explain their current significance.

Kalore, Niraj V; Gioe, Terence J; Singh, Jasvinder A



Minimum Two-Year Outcomes of Modular Bicompartmental Knee Arthroplasty.  


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 31months (range, 24-46months). 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 3years 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



Total hip arthroplasty using the superior capsulotomy technique.  


Dislocation of the native hip during total hip arthroplasty has traditionally been an integral part of all surgical exposures. However, dislocation of the native hip may require greater soft-tissue release than surgical excision of the femoral head during total hip arthroplasty. The superior capsulotomy technique allows preparation of the femur in situ, with excision of the femoral head after femoral component preparation has been completed. The advantages of this technique include preservation of the hip joint capsule and less tissue dissection during surgery; special traction equipment or fluoroscopy is not needed. This technique allows immediate mobilization of patients without motion or weight-bearing precautions, little parental narcotic use, and discharge home within 24 hours of surgery for most patients. PMID:23395030

Murphy, Stephen B



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.

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



Easy Identification of Mechanical Axis during Total Knee Arthroplasty.  


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; Park, Sang-Hoon



Thirty-Day Morbidity and Mortality of the Laparoscopic Ileal Interposition Associated with Sleeve Gastrectomy for the Treatment of Type 2 Diabetic Patients with BMI <35: An Analysis of 454 Consecutive Patients  

Microsoft Academic Search

Background  The objective of this study was to evaluate the early results of the laparoscopic interposition of a segment of ileum associated\\u000a with a sleeve gastrectomy (LII-SG) in order to treat patients with type 2 diabetes mellitus (T2DM) and BMI <35. Data regarding\\u000a morbidly obese diabetic patients subjected to surgery has consistently been validated. To date, there is scarce information\\u000a about

Aureo L. DePaulaAlessandro; Alessandro Stival; Alfredo Halpern; Sergio Vencio



[Interposition of a full-thickness skin graft in the surgery of temporomandibular joint ankylosis. A study of 31 cases of which 20 had long-term follow-up].  


Recurrence is the main problem in temporo-mandibular joint ankylosis treatment. Two therapy are used against this, physiotherapy and surgical joint interposition. Following ankylosis removal, many materials can be interposed but, for us, fullthickness skin graft using Popescu and Vasiliu technique seems to be the best and simplest one. This retrospective study of 31 cases, 20 with long-term follow-up, shows that good results are obtained using this skin graft, with 90% successful rate. PMID:8650497

Guyot, L; Chossegros, C; Cheynet, F; Gola, R; Lachard, J; Blanc, J L



Parsonage-Turner syndrome after total-hip arthroplasty  

Microsoft Academic Search

A 68-year-old patient developed Parsonage-Turner syndrome after total hip arthroplasty. There was an acute onset of intense pain in the shoulder 48 hours after surgery followed by complete paralysis of the shoulder and almost complete loss of strength in the arm. Recovery was slow, and mild weakness persisted 7 years after the operation. Parsonage-Turner syndrome has been associated with various

Jean-Pierre A Simon; Guy Fabry



Indomethacin as a postoperative analgesic for total hip arthroplasty  

Microsoft Academic Search

This prospective, randomized, double-blind trial evaluated the efficacy of rectal indomethacin as an adjunct to morphine for\\u000a controlling postoperative pain. Fifty healthy patients undergoing elective hip arthroplasty were investigated. Group 1 (n\\u000a = 25) received placebo suppositories. Group 2 (n = 25) received indomethacin suppositories, 100 mg q8hr for five doses, starting\\u000a at the end of the procedure. Both groups

R. Segstro; P. K. Morley-Forster; G. Lu



Hammertoe surgery: arthroplasty, arthrodesis or plantar plate repair?  


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



Dysfunction of the posterior cruciate ligament in total knee arthroplasty  

Microsoft Academic Search

Purpose  Total knee arthroplasty (TKA) is typically carried out either with retention (CR) of the posterior cruciate ligament (PCL)\\u000a or with sacrifice of this ligament and implantation of a posterior stabilised (PS) prosthesis. This paper investigates a comparison\\u000a of PCL function in knees treated for osteoarthritis with TKA where the PCL is preserved to those knees treated with TKA and\\u000a posterior

James Edmund Arbuthnot; Olwyn Wainwright; Gareth Stables; Manickam Rathinam; David I. Rowley; Michael J. McNicholas



The First 50 Years of Total Hip Arthroplasty: Lessons Learned  

Microsoft Academic Search

Fifty years have passed since the first total hip arthroplasty of the modern era was performed. At this, the vantage point,\\u000a it is reasonable to review these five decades, inquiring behind the single dominating observation that, in its current form,\\u000a this operation is one of the most successful of all surgical procedures for the management of end-stage human disease. What

William H. Harris



Massive structural allograft in revision of septic hip arthroplasty  

Microsoft Academic Search

We reviewed 10 patients who had undergone two-stage reconstruction with massive structural allografts following failure of hip arthroplasty due to infection. The mean follow-up time was more than 5 years (range 3-10 years). There was no case of the infection recurring. The most common pathogen isolated at the time of first-stage surgery was Staphylococcus epidermidis. The mean preoperative modified Harris

I. Ilyas; D. A. F. Morgan



Primary total hip arthroplasty in patients with rheumatoid arthritis  

Microsoft Academic Search

Twenty-eight (11 cemented and 17 noncemented) total hip arthroplasties (THA) were performed in 20 patients with rheumatoid arthritis (RA). The average age at operation was 42.1 years and the average follow-up was 10.8 years. There were two deep infections requiring removal of the prosthesis. Three cemented acetabular cups and one cemented femoral component were revised due to aseptic loosening. One

W. M. Tang; K. Y. Chiu



Poor accuracy of freehand cup positioning during total hip arthroplasty  

Microsoft Academic Search

Several studies have demonstrated a correlation between the acetabular cup position and the risk of dislocation, wear and\\u000a range of motion after total hip arthroplasty. The present study was designed to evaluate the accuracy of the surgeon’s estimated\\u000a position of the cup after freehand placement in total hip replacement. Peroperative estimated abduction and anteversion of\\u000a 200 acetabular components (placed by

B. H. Bosker; C. C. P. M. Verheyen; W. G. Horstmann; N. J. A. Tulp



Tibial stress fracture after computer-navigated total knee arthroplasty  

Microsoft Academic Search

A correct alignment of the tibial and femoral component is one of the most important factors determining favourable long-term\\u000a results of a total knee arthroplasty (TKA). The accuracy provided by the use of the computer navigation systems has been widely\\u000a described in the literature so that their use has become increasingly popular in recent years; however, unpredictable complications,\\u000a such as

F. Massai; F. Conteduca; A. Vadalà; R. Iorio; L. Basiglini; A. Ferretti



Arthrodesis of the knee after failed infected total knee arthroplasty  

Microsoft Academic Search

Infection after total knee arthroplasty (TKA) can be a challenging and difficult problem to treat. In selected patients, knee\\u000a arthrodesis is a well-recognized salvage procedure after infected TKA. The authors retrospectively reviewed their experience\\u000a with this treatment option, presenting 20 patients (8 women, 12 men), performed between 1990 and 2002. The average age was\\u000a 67 years (range: 47–81 years) and

Hans-Michael Klinger; Gunter Spahn; Wolfgang Schultz; Mike Herbert Baums



ARTHROBOT : a new surgical robot system for total hip arthroplasty  

Microsoft Academic Search

This paper presents mechanisms and control methods of a new surgery robot for total hip arthroplasty (THA). To minimize the disadvantages of the conventional registration method, a new gauge-based registration method has been proposed, and a 3-DOF robot has been developed that can be mounted on a femur The proposed surgical robot can operate along a pre-programmed path autonomously, in

Dong-Soo Kwon; Yong-San Yoon; Jung-Ju Lee; Seong-Young Ko; Kwan-Hoe Huh; Jong-Ha Chung; Young-Bae Park; Chung-Hee Won



Treatment of advanced carpometacarpal joint disease: trapeziectomy and hematoma arthroplasty.  


Some surgical treatment options of painful basal joint arthritis do not require complex arthroplasty or suspensionplasty techniques. Simple trapeziectomy with temporary pinning of a slightly overdistracted thumb metacarpal can provide reliable pain relief, good motion, and functional stability. Recent literature supports alternative options when compared with formal ligament reconstruction or suspensionplasty procedures. Simple trapeziectomy is associated with less morbidity due to shorter operative times and the lack of need for graft harvest and ligament reconstruction. PMID:18675718

Fitzgerald, Brian T; Hofmeister, Eric P



Perioperative Hyperglycemia and Postoperative Infection after Lower Limb Arthroplasty  

PubMed Central

Background One of the most serious complications after major orthopedic surgery is deep wound or periprosthetic joint infection. Various risk factors for infection after hip and knee replacement surgery have been reported, including patients' comorbidities and surgical technique factors. We investigated whether hyperglycemia and diabetes mellitus (DM) are associated with infection that requires surgical intervention after total hip and knee arthroplasty. Methods We reviewed our computerized database for elective primary total hip and knee arthroplasty from 2000 to 2008. Demographic information, past medical history of patients, perioperative biochemistry, and postoperative complications were reviewed. Patients were divided into two groups: infected group (101 patients who had surgical intervention for infection at our institution within 2 years after primary surgery) and noninfected group (1847 patients with no intervention with a minimum of one year follow-up. The data were analyzed using t, chi-squared, and Fisher's exact tests. Results There were significantly more diabetes patients in the infected group compared with the noninfected group (22% versus 9%, p < .001). Infected patients had significantly higher perioperative blood glucose (BG) values: preoperative BG (112 ± 36 versus 105 ± 31 mg/dl, p = .043) and postoperative day (POD) 1 BG (154 ± 37 versus 138 ± 31 mg/dl, p < .001). Postoperative morning hyperglycemia (BG >200 mg/dl) increased the risk for the infection more than two-fold. Non-DM patients were three times more likely to develop the infection if their morning BG was >140 mg/dl on POD 1, p = .001. Male gender, higher body mass index, knee arthroplasty, longer operative time and hospital stay, higher comorbidity index, history of myocardial infarction, congestive heart failure, and renal insufficiency were also associated with the infection. Conclusions Diabetes mellitus and morning postoperative hyperglycemia were predictors for postoperative infection following total joint arthroplasty. Even patients without a diagnosis of DM who developed postoperative hyperglycemia had a significantly increased risk for the infection.

Mraovic, Boris; Suh, Donghun; Jacovides, Christina; Parvizi, Javad



Supracondylar nailing of periprosthetic fractures above total knee arthroplasties  

Microsoft Academic Search

Supracondylar nailing was performed in 10 patients who sustained periprosthetic fractures above total knee arthroplasties.\\u000a The fractures occurred in women with an average age of 67.4 years (range, 42–92 years). All fractures healed in a satisfactory\\u000a alignment in an average duration of 13.2 weeks (range, 12–18 weeks). None of the fractures needed bone grafting. There were\\u000a no cases of wound

A. Kumar; M. Catre; P. Weiler; S. Butt



Total hip arthroplasty for active tuberculosis of the hip  

Microsoft Academic Search

Total hip arthroplasty (THA) has been used as a successful form of treatment in patients with long-standing tuberculosis,\\u000a but it is unclear whether THA should be performed in patients with current infection. We performed THA in six patients with\\u000a advanced active tuberculosis of the hip from 2002 to 2006. Tuberculosis was confirmed in all cases by histological examination.\\u000a All patients

Yongqing Wang; Jingsheng Wang; Zhanmin Xu; Yuan Li; Huimin Wang



Cementless total hip arthroplasty for the management of tuberculosis coxitis  

Microsoft Academic Search

Introduction  Tuberculosis arthritis of the hip is a crippling disease and there is need for an effective and acceptable treatment for the\\u000a hips with bone destruction. The aim of this report was to evaluate the efficacy of the diagnostic method for hip tuberculosis\\u000a and clinical results of the patients to clarify the question of whether a total hip arthroplasty (THA) should

Yusuf Öztürkmen; Mahmut Karamehmeto?lu; Cem Leblebici; Alper Gökçe; Mustafa Caniklio?lu



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



Patellar clunk syndrome after posterior stabilized total knee arthroplasty  

Microsoft Academic Search

Two hundred thirty-six posterior stabilized total knee arthroplasties (TKAs) were performed consecutively. Twenty-seven patellar clunk syndromes were identified in 25 patients. Insall-Salvati ratio, position of joint line, postoperative patellar height, and anterior-posterior position of tibial tray were measured. It was found that postoperative low-lying patella (P<.001) and anterior placement of tibial tray (P=.011) was associated with patellar clunk syndrome. Thirteen

Wai-Pan Yau; Jimmy W. K Wong; Kwong-Yuen Chiu; Tze-Pui Ng; Wai-Man Tang



Ceramic coating improves tibial component fixation in total knee arthroplasty  

Microsoft Academic Search

Forty uncemented total knee arthroplasties (36 patients) were randomly allocated to a Miller-Galante II prosthesis with or without hydroxyapatite\\/tricalcium phosphate (HA\\/TCP) coating on the titanium fiber mesh on the undersurface of the tibial component. The patients were followed for 2 years with repeated radiostereometric examinations. After 2 years, the HA\\/TCP tibial components displayed smaller anterior-posterior tilt and less subsidence. The

Lars Regnér; Lars Carlsson; Johan Kärrholm; Peter Herberts



Modern Total Hip Arthroplasty in Patients Younger Than 21 Years  

Microsoft Academic Search

Total hip arthroplasty (THA) is not commonly performed in adolescents. However, it may be the only option for pain control with continued mobility for advanced disease. We report our experience with modern alternative-bearing THA in patients younger than 21 years. Twenty-one THAs (18 patients) were followed. Preoperative and postoperative Harris hip scores were recorded, and radiographs were reviewed. Average follow-up

Atul F. Kamath; Neil P. Sheth; Harish H. Hosalkar; Oladapo M. Babatunde; Gwo-Chin Lee; Charles L. Nelson


Revision surgery for patellar dislocation after primary total knee arthroplasty  

Microsoft Academic Search

This study evaluated risk factors for patellar dislocation after primary total knee arthroplasty and determined functional outcomes in patients following revision. Thirty-nine knees in 39 patients averaging 68 years (range, 27–91 years) at the time of revision were evaluated at a mean of 3.2 years (range, 2–7 years). Mean Knee Society and Function scores significantly improved from 34 and 35

Kingsley R. Chin; Donald S. Bae; Jess H. Lonner; Richard D. Scott



Minimally invasive total hip arthroplasty: a systematic review  

Microsoft Academic Search

The purpose of this study was to compare the operative outcome between mini and standard incisions in total hip arthroplasty\\u000a (THA). We identified 12 randomised or quasi-randomised control trials (RCT or qRCT) published between 1996 and 2008. Subgroup\\u000a and sensitivity analyses were performed to evaluate the differences in results for surgical approach, trial quality, and follow-up\\u000a duration. Operative time and

T. Cheng; J. G. Feng; T. Liu; X. L. Zhang



Evaluation of the Hemocue portable hemoglobinometer after major joint arthroplasty.  


We evaluated the potential use of the Hemocue (Hemocue AB, Sweden) portable hemoglobinometer on the 1st postoperative evening after major joint arthroplasty. We compared hemoglobinometer values with conventional Coulter counter laboratory analysis in a population of 67 patients. The hemoglobinometer proved practical, economical, and accurate in general, although 2 outlying values were severe enough as potentially to influence clinical decision making. Potential causes and solutions are discussed. PMID:11847624

Teli, Marco; Ng, Yeung; Ingram, Roland



Revision total hip arthroplasty with proximal bone loss.  


The presence of a deficient or mechanically compromised proximal femur represents a particular challenge to revision total hip arthroplasty. This article details the results of reconstructing these challenging cases using a modular, tapered, and distally fixed femoral stem component that allows independent control of length, offset, and anteversion of the femur. Mid-term results suggest that distal fixation in the presence of a deficient or mechanically compromised femur is a reliable solution to these difficult problems. PMID:15190565

Murphy, Stephen B; Rodriguez, Jose



Soft-Tissue Balance in Total Knee Arthroplasty  

Microsoft Academic Search

Dictionary defi nitions of balance include “a state where things are of equal weight or force” and “to be in a position where\\u000a you will stand without falling to either side”. Modern total condylar knee arthroplasty began in the latter half of the 1970s\\u000a and at that time the patient population was elderly and quite happy to use a stick

David E. Beverland


Does Regional Anesthesia Improve Outcome After Total Knee Arthroplasty?  

Microsoft Academic Search

Total knee arthroplasty (TKA) is amenable to various regional anesthesia techniques that may improve patient outcome. We sought\\u000a to answer whether regional anesthesia decreased mortality, cardiovascular morbidity, deep venous thrombosis and pulmonary\\u000a embolism, blood loss, duration of surgery, pain, opioid-related adverse effects, cognitive defects, and length of stay. We\\u000a also questioned whether regional anesthesia improved rehabilitation. To do so, we

Alan J. R. Macfarlane; Govindarajulu Arun Prasad; Vincent W. S. Chan; Richard Brull



Gapped ferromagnetic graphene nanoribbons.  


We theoretically design a graphene-based all-organic ferromagnetic semiconductor by terminating zigzag graphene nanoribbons (ZGNRs) with organic magnets. A large spin-split gap with a 100% spin polarized density of states near the Fermi energy is obtained, which is of potential application in spin transistors. The interactions among electron, spin and lattice degrees of freedom are studied using the first-principles calculations including non-collinear spin orientations. All of the calculations consistently demonstrate that although no d electrons existing, the antiferromagnetic ?-? exchange together with the strong electron-lattice interactions between organic magnets and ZGNRs make the ground state ferromagnetic. PMID:21706114

Hou, Dong; Wei, Jianhua; Xie, Shijie



Mind the gap.  

SciTech Connect

In this summary of the application of Dyson-Schwinger equations to the theory and phenomenology of hadrons, some deductions following from a nonperturbative, symmetry-preserving truncation are highlighted, notable amongst which are results for pseudoscalar mesons. We also describe inferences from the gap equation relating to the radius of convergence of a chiral expansion, applications to heavy-light and heavy-heavy mesons, and quantitative estimates of the contribution of quark orbital angular momentum in pseudoscalar mesons; and recapitulate upon studies of nucleon electromagnetic form factors.

Bhagwat, M. S.; Krassnigg, A.; Maris, P.; Roberts, C. D.; Physics; Univ. Graz; Univ. of Pittsburgh



Effect of surgeon fatigue on hip and knee arthroplasty  

PubMed Central

Background There is growing support in the literature that patient outcomes are adversely affected by physician fatigue in operator-dependent cognitive and technical tasks. Recent increases in total joint arthroplasty caseloads have resulted in longer operative days and increased surgeon fatigue. We sought to determine if time of day predicts perioperative complications and outcomes in total joint arthroplasty. Methods The records of all total hip and knee arthroplasties (THA; TKA) performed for primary osteoarthritis in one calendar year at one large university hospital were retrospectively reviewed. Demographic data, surgery start time and duration, intraoperative complications, radiographic component alignment and functional outcome scores (SF-12 and Western Ontario and McMaster Universities Osteoarthritis Index) were collected and analyzed using linear and nonparametric rank correlation statistics. Data were corrected for sex, body mass index, surgeon and postcall operating days. Results In the THA cohort (n = 341), a later surgery start time was significantly related to duration of surgery (p = 0.004, mean difference ?7.1 min). There was a trend toward significance between a later surgery start time and intraoperative femur fracture (p = 0.05). Postoperative complications, component alignment and functional outcome scores were not significantly affected by surgery start time. There were no significant findings for any of the intraoperative or postoperative outcomes in the TKA cohort (n = 292). Conclusion Duration of surgery and incidence of intraoperative complications for THA may increase with later surgery start time; however, the relatively small statistical differences observed imply that they likely are not clinically significant.

Peskun, Christopher; Walmsley, David; Waddell, James; Schemitsch, Emil



Total hip arthroplasty in the very young patient.  


The surgical management of end-stage hip disease in patients aged <30 years remains a challenge. Hip-preserving surgical procedures in the setting of advanced disease often do not provide adequate pain relief, but the implications of joint arthroplasty surgery in the very young patient are a matter of concern. The outcome of total hip arthroplasty (THA) in these patients varies, largely because of the wide spectrum of diagnoses associated with hip disease in this group, the complexity of deformities requiring THA, and the need for prolonged durability. The greatest number of THAs in this population is performed for secondary osteoarthritis or osteonecrosis, whereas most reports in the orthopaedic literature have focused on the outcomes of cemented THA in patients with juvenile rheumatoid arthritis. Given the frequent complexity of THA in the very young patient, special attention should be given to preoperative planning, implant selection, and patient education as well as to joint-preservation techniques to facilitate future hip arthroplasty surgery. PMID:22855851

Polkowski, Gregory G; Callaghan, John J; Mont, Michael A; Clohisy, John C



Principles of joint arthroplasty as applied to the ankle.  


The challenges for the development of a successful total ankle prosthesis are formidable. The forces at the ankle are large and the surface area for bone support is [figure: see text] small. The size and shape of the talus make expansion of the surface area for fixation very difficult and greatly minimize options for prosthetic revision. The quality of bone in the distal tibia frequently may be questionable, and the bone strength is not uniform across the distal tibia. Finally, the soft-tissue envelope at the ankle is poor. The distal location of the ankle magnifies the circulatory risk in any patient with peripheral vascular disease. Wound problems are more common and more dangerous than in more proximal sites. Fractures and other injuries are very common at the ankle and potentially can add to the frequency of complications. The proximity of the medial and anterior neurovascular structures also increases the likelihood of serious complication. Total ankle arthroplasty is much closer to the limit of what can be successfully accomplished with acceptable risk to the patient. There is little room for error. This, coupled with the larger compressive forces generated at the ankle, makes successful ankle arthroplasty a bigger challenge than arthroplasty at the hip or knee. PMID:12064096

Gill, Lowell H



Obesity in total hip arthroplasty--does it really matter?  

PubMed Central

Background and purpose Discussion persists as to whether obesity negatively influences the outcome of hip arthroplasty. We performed a meta-analysis with the primary research question of whether obesity has a negative effect on short- and long-term outcome of total hip arthroplasty. Methods We searched the literature and included studies comparing the outcome of hip arthroplasty in different weight groups. The methodology of the studies included was scored according to the Cochrane guidelines. We extracted and pooled the data. For continuous data, we calculated a weighted mean difference and for dichotomous variables we calculated a weighted odds ratio (OR). Heterogeneity was calculated using I2 statistics. Results 15 studies were eligible for data extraction. In obese patients, dislocation of the hip (OR = 0.54, 95% CI: 0.38–0.75) (10 studies, n = 8,634), aseptic loosening (OR = 0.64, CI: 0.43–0.96) (6 studies, n = 5,137), infection (OR = 0.3, CI: 0.19–0.49) (10 studies, n = 7,500), and venous thromboembolism (OR = 0.56, CI: 0.32–0.98) (7 studies, n = 3,716) occurred more often. Concerning septic loosening and intraoperative fractures, no statistically significant differences were found, possibly due to low power. Subjective outcome measurements did not allow pooling because of high heterogeneity (I2 = 68%). Interpretation Obesity appears to have a negative influence on the outcome of total hip replacement.



Anterior muscle sparing approach for total hip arthroplasty  

PubMed Central

The purpose of this review is to examine the validity of positive claims regarding the direct anterior approach (DAA) with a fracture table for total hip arthroplasty. Recent literature regarding the DAA was searched and specific claims investigated including improved early outcomes, speed of recovery, component placement, dislocation rates, and complication rates. Recent literature is positive regarding the effects of total hip arthroplasty with the anterior approach. While the data is not definitive at present, patients receiving the anterior approach for total hip arthroplasty tend to recover more quickly and have improved early outcomes. Component placement with the anterior approach is more often in the “safe zone” than with other approaches. Dislocation rates tend to be less than 1% with the anterior approach. Complication rates vary widely in the published literature. A possible explanation is that the variance is due to surgeon and institutional experience with the anterior approach procedure. Concerns remain regarding the “learning curve” for both surgeons and institutions. In conclusion, it is not a matter of should this approach be used, but how should it be implemented.

Moskal, Joseph T; Capps, Susan G; Scanelli, John A



Infection prevention methodologies for lower extremity total joint arthroplasty.  


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



Clinical and Economic Burden of Revision Knee Arthroplasty  

PubMed Central

Surgery is indicated for symptomatic knee osteoarthritis (OA) when conservative measures are unsuccessful. High tibial osteotomy (HTO), unicompartmental knee arthroplasty (UKA), and total knee arthroplasty (TKA) are surgical options intended to relieve knee OA pain and dysfunction. The choice of surgical intervention is dependent on several factors such as disease location, patient age, comorbidities, and activity levels. Regardless of surgical treatment, complications such as infection, loosening or lysis, periprosthetic fracture, and postoperative pain are known risks and are indications for revision surgery. The clinical and economic implications for revision surgery are underappreciated. Over 55,000 revision surgeries were performed in 2010 in the US, with 48% of these revisions in patients under 65 years. Total costs associated with each revision TKA surgery have been estimated to be in excess of $49,000. The current annual economic burden of revision knee OA surgery is $2.7 billion for hospital charges alone. By 2030, assuming a 5-fold increase in the number of revision procedures, this economic burden will exceed $13 billion annually. It is appealing to envision a therapy that could delay or obviate the need for arthroplasty. From an actuarial standpoint, this would have the theoretical downstream effect of substantially reducing the number of revision procedures. Although no known therapies currently meet these criteria, such a breakthrough would have a tremendous impact in lessening the clinical and economic burden of knee OA revision surgery.

Bhandari, Mohit; Smith, Jon; Miller, Larry E.; Block, Jon E.



Mini-invasive knee unicompartmental arthroplasty: bone-sparing technique.  


Total knee replacement (TKR) has been well accepted as the definitive knee- salvage procedure. Existence of a predictable, reproducible, salvage procedure has allowed for re-evaluation of other surgical techniques, such as unicompartmental arthroplasty, to prolong or preserve knee function. Knee osteoarthritis has been described as highly segmental, primarily medial, and slowly progressive. Loss of articular cartilage is compensated by development of sclerotic bone, which although it supports weight, it deforms with weight-bearing and produces pain. Ligament imbalance is not compensated. A mini-invasive knee arthroplasty has been developed that features the following three criteria: (1) minimizes physiologic damage, (2) minimizes interference in life style, and (3) avoids interference with future treatment options. Unicompartmental knee arthroplasty can, therefore, be performed as a low-morbidity outpatient procedure while preserving bone for future TKR--in essence, a pre-TKR procedure. Techniques include limited surgical exposure, internal landmarks for prosthetic insertion, and pain management to facilitate out-patient status. PMID:12931312

Repicci, John A



Circulating Cytokines after Hip and Knee Arthroplasty: A Preliminary Study  

PubMed Central

Several studies show cytokine concentrations in the peripheral blood are associated with inflammatory activity and surgical trauma. Cytokine concentrations have more rapid increase and quicker return to normal values than either C-reactive protein or erythrocyte sedimentation rate – a matter of hours rather than weeks; some studies suggest they are better predictors of postoperative infection than C-reactive protein and erythrocyte sedimentation rate. Threshold levels of interleukin-6 after joint arthroplasty have been determined, but levels of other potentially useful cytokines (tumor necrosis factor-?, interleukin-8, interleukin-10, etc) are not known. We measured the serum levels of 25 different cytokines before and after hip and knee arthroplasties and identified those associated with surgical trauma. Peripheral venous blood samples (one preoperative and three postoperative) from 49 patients undergoing hip or knee arthroplasty were analyzed by laser chromatography. Three of the 25 cytokines had a relationship with postsurgical trauma, which included one deep infection. Serum levels of these three cytokines might be useful to identify periprosthetic infections during the early postoperative period when C-reactive protein and erythrocyte sedimentation rate remain elevated. Level of Evidence: Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Mohammed, Aslam; Patil, Sanjeev; McFadyen, Angus; Meek, R. M. D.



Periprosthetic Femoral Supracondylar Fracture After Total Knee Arthroplasty With Navigation System  

Microsoft Academic Search

We report 1 patient with a supracondylar periprosthetic fracture 1 month after computer-assisted total knee arthroplasty. The fracture line extended from previous anchoring pinholes into the supracondyle area. Intramedullary nailing of the left femur was performed under close reduction. The possible complication of pinhole fracture to total knee arthroplasty with navigation system should be kept in mind.

Chi-Huan Li; Tain-Hsiung Chen; Yu-Ping Su; Po-Chou Shao; Kung-Sheng Lee; Wei-Ming Chen



The Mennen femoral plate for fixation of periprosthetic femoral fractures following hip arthroplasty  

Microsoft Academic Search

Periprosthetic fractures can be treated by various methods. The Mennen femoral plate used to be a common implant in our region to stabilise periprosthetic femoral fractures following hip arthroplasty.This device has been used in 16 patients in our region from three different centres. The periprosthetic femoral fractures occurred approximately 7 years after the hip arthroplasty procedure. After stabilisation of the

Sashin Ahuja; S Chatterji



Results after 562 total elbow replacements: A report from the Norwegian Arthroplasty Register  

Microsoft Academic Search

Background: The aim of this study was to give results of elbow arthroplasty for a relatively large popu- lation and compare different prosthesis brands and different patient subgroups. Methods: Between 1994 and 2006, 562 total elbow replacement operations were reported to the Norwe- gian Arthroplasty Register. Revisions of prostheses were shown using Kaplan-Meier failure curves, and risk of revision was

Bjørg-Tilde S. Fevang; Stein A. Lie; Leif I. Havelin; Arne Skredderstuen; Ove Furnes



Diagnostic values of positron emission tomography versus triple-phase bone scan in hip arthroplasty loosening  

Microsoft Academic Search

Introduction The most frequent complications of total hip arthroplasty are septic and aseptic wear- induced loosening. A reliable differentiation between septic and aseptic loosening with current diagnostic tools is not possible. Therefore, we examined the diag- nostic valency of positron emission tomography (PET) with 18 F-fluorodeoxyglucose (FDG) in cases of septic or aseptic hip arthroplasty loosening compared with con- ventional

T. Mumme; P. Reinartz; J. Alfer; R. Müller-Rath; U. Buell; D. C. Wirtz



Arthroplasty Utilization in the United States is Predicted by Age-Specific Population Groups  

PubMed Central

Osteoarthritis is a common indication for hip and knee arthroplasty. An accurate assessment of current trends in healthcare utilization as they relate to arthroplasty may predict the needs of a growing elderly population in the United States. First, incidence data was queried from the United States Nationwide Inpatient Sample from 1993 to 2009. Patients undergoing total knee and hip arthroplasty were identified. Then, the United States Census Bureau was queried for population data from the same study period as well as to provide future projections. Arthroplasty followed linear regression models with the population group >64 years in both hip and knee groups. Projections for procedure incidence in the year 2050 based on these models were calculated to be 1,859,553 cases (hip) and 4,174,554 cases (knee). The need for hip and knee arthroplasty is expected to grow significantly in the upcoming years, given population growth predictions.

Bashinskaya, Bronislava; Zimmerman, Ryan M.; Walcott, Brian P.; Antoci, Valentin



Bone mineral density changes after total knee arthroplasty: one-year follow-up.  


The study involved analysis of differences in bone mineral density (BMD) in the region of knee arthroplasty in 106 female patients. BMD was assessed using dual-energy X-ray absorptiometry in a follow-up time schedule: before surgery and 2 weeks postoperatively (baseline), 5, 12, 24, and 48 weeks after knee joint arthroplasty. Four assessment regions A, B, C, and D were determined in immediate proximity to the arthroplasty site. A year after surgery, a decrease in BMD was observed in all determined regions-(9.9%, 13.8%, 9.9%, and 7.6% respectively) in comparison with the baseline value. The most significant BMD decrease was observed in the period between 5 and 12 weeks after the knee joint arthroplasty. In our opinion, the decrease in BMD at the knee joint arthroplasty site is a result of the postoperative increased bone resorption and decreased patient motor activity. PMID:18619880

Gazdzik, Tadeusz S; Gajda, Tomasz; Kaleta, Marek



Hip resurfacing arthroplasty: short-term survivorship of 4,401 hips from the Finnish Arthroplasty Register  

PubMed Central

Background and purpose Population-based registry data from the Nordic Arthroplasty Register Association (NARA) and from the National Joint Register of England and Wales have revealed that the outcome after hip resurfacing arthroplasty (HRA) is inferior to that of conventional total hip arthroplasty (THA). We analyzed the short-term survival of 4,401 HRAs in the Finnish Arthroplasty Register. Methods We compared the revision risk of the 4,401 HRAs from the Register to that of 48,409 THAs performed during the same time period. The median follow-up time was 3.5 (0–9) years for HRAs and 3.9 (0–9) years for THAs. Results There was no statistically significant difference in revision risk between HRAs and THAs (RR = 0.93, 95% CI: 0.78–1.10). Female patients had about double the revision risk of male patients (RR = 2.0, CI: 1.4–2.7). Hospitals that had performed 100 or more HRA procedures had a lower revision risk than those with less than 100 HRAs (RR = 0.6, CI: 0.4–0.9). Articular Surface Replacement (ASR, DePuy) had inferior outcome with higher revision risk than the Birmingham Hip Resurfacing implant (BHR, Smith & Nephew), the reference implant (RR = 1.8, CI: 1.2–2.7). Interpretation We found that HRA had comparable short-term survivorship to THA at a nationwide level. Implant design had an influence on revision rates. ASR had higher revision risk. Low hospital procedure volume worsened the outcome of HRA. Female patients had twice the revision risk of male patients.



Ileal interposition surgery-induced improvement of hyperglycemia and insulin resistance in Goto-Kakizaki rats by upregulation of TCF7L2 expression  

PubMed Central

The aim of this study was to investigate the effects of ileal interposition (IT) on glucose and insulin resistance (IR) in type 2 diabetic mellitus (T2DM), and the role of T-cell factor 7-like 2 (TCF7L2), formerly known as TCF4, in the downregulation of hyperglycemia following IT. Goto-Kakizaki (GK) rats subjected to IT surgery (GK-IT group), GK rats subjected to sham surgery (GK-Sham group) and Wistar (WS) rats subjected to sham surgery (WS-Sham group) were investigated in this study. Fasting plasma glucose, body weight, food intake per 1 kg body weight, insulin and a homeostasis model assessment of insulin resistance (HOMA-IR) were measured pre- and post-surgery. The rats were euthanized 28 days post-surgery and the pancreas of each rat was dissected. The expression levels of TCF7L2 mRNA and protein were analyzed by quantitative RT-PCR and western blotting, respectively. Our results revealed that IT improved both fasting plasma glucose levels and IR in GK rats by upregulating the expression of the TCF7L2 protein. IT provides a valuable therapeutic option for patients with T2DM. Upregulation of TCF7L2 protein expression may be a possible mechanism underlying the improvement of T2DM following IT.




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.



Gap and stripline combined monitor  


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.



Measuring improvement following total hip and knee arthroplasty using the SF-36 Health Survey.  


The aim of this study was to evaluate the impact of total hip or knee arthroplasty upon quality of life in elderly patients. The study was carried out at the Clinic for Orthopaedic Surgery Lovran on 74 total hip arthroplasty and 70 total knee arthroplasty patients. All patients had completed the Medical Outcomes Study 36-Item Short Form in the week having preceded their surgery and then again postoperatively, 2 years after. The data obtained were statistically processed at the level of physical function, role limitations due to physical problems, role limitations due to emotional problems, social function, mental health, energy or vitality, pain and general health perception, and change in health. The primary total hip arthroplasty patients showed significant improvement at all levels measured. Similarly, the primary total knee arthroplasty patients expressed significant improvement according to all the parameters but the mental health assessment. Comparison of outcomes between the two assessment groups of patients resulted in slightly superior quality of life outcomes in total hip arthroplasty patients. It can be concluded that total hip or knee arthroplasty significantly enhances the health related quality of life in elderly patients. PMID:22816222

Santi?, Veljko; Legovi?, Dalen; Sestan, Branko; Jurdana, Hari; Marinovi?, Marin



Venous thromboembolism associated with hip and knee arthroplasty: current prophylactic practices and outcomes.  


Joint registry and hospital data bases for 5,024 total hip and total knee arthroplasties done between 1986 and 1988 at the Mayo Clinic were used to study prophylactic measures and frequency of symptomatic deep venous thrombosis and pulmonary embolism. In virtually all patients, graduated compression stockings were used, with or without another type of prophylaxis. Only 44 of 3,115 patients who underwent hip arthroplasty (1.4%) and 32 of 1,909 patients who underwent knee arthroplasty (1.7%) had definite or probable deep venous thrombosis or pulmonary embolism. Death definitely or possibly attributable to pulmonary embolism occurred in 11 patients who underwent hip arthroplasty (0.35%) and 1 patient who underwent knee arthroplasty (0.05%). Although patients with a history of deep venous thrombosis or pulmonary embolism were more likely to receive warfarin than were patients without such a history, the relative risk of symptomatic deep venous thrombosis or pulmonary embolism in patients who underwent hip arthroplasty and received warfarin postoperatively was approximately half that in patients who received other types of prophylaxis. The risk of death from pulmonary embolism was similarly diminished in the group that received warfarin. The lower rates of these complications in the patients who received warfarin support the prophylactic use of this agent after total hip arthroplasty. PMID:1434931

Mohr, D N; Silverstein, M D; Ilstrup, D M; Heit, J A; Morrey, B F



Novel Gapped Quantum Wire  

NASA Astrophysics Data System (ADS)

High quality state of the art quantum wires (QWRs) can be fabricated by the novel cleaved edge overgrowth technique, proposed by (Pfeiffer et al., 1990). Transverse quantization in these QWRs leads to a succession of nested energy bands. With the lowest two successive energy levels occupied, gapped phases are possible including, e.g, an intersubband charge density wave (ICDW) and a Cooper phase with strong superconducting fluctuations (Starykh et al., 2000). Due to the possibility of density reorganization, in which it becomes favorable for the two lowest subbands to match their densities, the ICDW is usually the most likely state. Recently, by exploiting the valley degeneracy in AlAs, a single QWR has been fabricated with two degenerate nonoverlapping bands separated in k space by half an Umklapp vector (Moser et al. 2004). For low densities this structure is able to access a multiple subband regime that is not subject to the density reorganizing ICDW, leaving the Cooper phase to flourish. Using Abelian bosonization, we explore the relevant interaction terms for this system, including Umklapp assisted Cooper scattering, and discuss the phase diagram.

Datta, Trinanjan



Novel Gapped Quantum Wire  

NASA Astrophysics Data System (ADS)

High quality state of the art quantum wires (QWRs) can be fabricated by the novel Cleaved Edge Overgrowth (CEO) technique, proposed by (Pfeiffer et al, 1990). Transverse quantization in these QWRs leads to a succession of nested energy bands. With the lowest two successive energy levels occupied, gapped phases are possible including, e.g., an intersubband charge density wave (ICDW) and a Cooper phase with strong superconducting fluctuations (Starykh et al, 2000). Due to the possibility of density reorganization, in which it becomes favorable for the two lowest subbands to match their densities, the ICDW is usually the most likely state. Recently, by exploiting the valley degeneracy in AlAs, a single QWR has been fabricated with two degenerate nonoverlapping bands separated in k space by half an Umklapp vector (Moser et al 2004). For low densities the structure is able to access a multiple subband regime that is not subject to the density reorganizing ICDW, leaving a Cooper phase to flourish. Using Abelian bosonization, we explore the relevant interaction terms for this system, including Umklapp assisted Cooper scattering and discuss the phase diagram.

Datta, Trinanjan



Deep vein thrombosis in shoulder arthroplasty - a prospective study  

PubMed Central

Background Shoulder arthritis of varied aetiology is often disabling and patients seek treatment for pain relief and restricted movements. Though non operative measures in the form of analgesics, physiotherapy and joint injections offer satisfactory results in the early stages; operative treatment in the form of joint replacements becomes necessary in late and advanced stages. The above operations are being performed more frequently in the recent years across the National Health Service [NHS] in the UK with increasing success in specialised units and the outcome of the operation is often rewarding. In addition to the other complications, risks of Deep vein thrombosis [DVT] and pulmonary embolism [PE] exists. Available evidence suggests a low incidence but the true risk has only been partially addressed. The final decision to consider thromboprophylaxis rests with the operating surgeon. It is important to carefully balance the clinical decision of thromboprophylaxis and bleeding with wound complications, which add considerable morbidity and mortality. To define the risk of DVT in this subgroup of patients is the initial step to enable better use of resources and achieve cost effectiveness. This we believe will provide robust evidence to help formulate guidelines for thromboprophylaxis in shoulder arthroplasty. Methods/design The aim will be to determine whether shoulder arthroplasties carry a risk of DVT. A cohort of 100 consecutive patients being considered for shoulder arthroplasty for degenerative arthritis, rotator cuff arthropathy, inflammatory arthropathy including rheumatoid arthritis will be prospectively included for the study. All eligible patients will be assessed clinically and screened for DVT in all 4 limbs both pre and postoperative with Doppler scans within a 6 week perioperative period. We aim to include the reasons for non inclusion of eligible patients and patient’s perspective of their general well being in relation to DVT. Discussion We present the risk of DVT associated with shoulder arthroplasties to establish a good quality evidence for thromboprophylaxis. The study is underway and we would further be able to define whether the general risk factors for DVT are relevant to shoulder replacements.



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



Modular hybrid total hip arthroplasty. Experimental study in dogs  

Microsoft Academic Search

Background  This prospective experimental study evaluated the surgical procedure and results of modular hybrid total hip arthroplasty\\u000a in dogs.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Ten skeletally mature healthy mongrel dogs with weights varying between 19 and 27 kg were used. Cemented modular femoral stems\\u000a and uncemented porous-coated acetabular cups were employed. Clinical and radiographic evaluations were performed before surgery\\u000a and at 30, 60, 90, 120, 180

Bruno W Minto; Cláudia Valéria S Brandão; Gilberto JC Pereira; Daniela Campagnol; Jaqueline Maria Mamprim; Carlos Roberto Padovani; José JT Ranzani



Indications for Reverse Total Shoulder Arthroplasty in Rotator Cuff Disease  

Microsoft Academic Search

Background  Reverse total shoulder arthroplasty (RTSA) was introduced to treat rotator cuff tear arthropathy but is now used to treat\\u000a a variety of problems. Although its use has expanded substantially since the FDA’s approval in 2004, the appropriateness in\\u000a patients with rotator cuff disease is unclear.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  We review the use of RTSA in patients with rotator cuff disease to (1) describe

Gregory N. Drake; Daniel P. O’Connor; T. Bradley Edwards



[The 12 keypoints for rehabilitation after total knee arthroplasty].  


The rehabilitation process after total knee arthroplasty (TKA) relies more and more on the family doctor. Many factors contribute to this development: the constantly increasing number of TKA performed, the reduced length of stay at the hospital and the rehabilitation process after TKA requiring care for 3 to 4 months. After this time, it is also of major importance to encourage patients to take up physical activities in order to limit the negative effects of sedentarity. The goal of this paper is to give family doctors an overview of the current knowledge in the area of rehabilitation after TKA for physicians. PMID:23346748

Luthi, François; Pereira, Luis Carlos; Jolles, Brigitte M



The effect of hip arthroplasty on the speed of walking.  


Osteoarthritis of the hip presents itself with gait disturbances, such as decreased speed of walking and limp, regardless of the presence of pain. In most cases, patients decide to undergo surgical procedure as a result of pain and walking difficulties. The purpose of this study was to analyze gait speed in a group of 86 patients who have undergone hip arthroplasty. The methodology has consisted of analysis of walking speed over a distance of 20 meters performed prior to and following surgical treatment. The results indicated that, in most cases, surgical treatment was associated with significant improvement in the speed of walking.   PMID:24042091

Pogorza?a, Adam M; Stry?a, Wanda; Nowakowski, Andrzej



A technique of extensile exposure for total hip arthroplasty.  


A technique of trochanteric osteotomy that allows extensile exposure of the hip and wide exposure of the proximal femoral diaphysis for total joint replacement is described. Pathologic conditions of the shaft encountered during arthroplasty can therefore be addressed. The approach is based on the preservation of an intact musculoosseous-muscular sleeve comprised of the gluteus medius, greater trochanter, and vastus lateralis and allows physiologic reconstruction of the hip's soft tissue envelope. This versatile approach is particularly useful in revision surgery and in difficult primary interventions where leg length is adjusted. The surgical technique, indications, and advantages are described. Early clinical results of 90 cases are presented. PMID:3572407

Glassman, A H; Engh, C A; Bobyn, J D



Biologic fixation arthroplasty in the treatment of osteonecrosis.  


To provide a possible solution to the problem of aseptic loosening of prosthetic hip replacement components, the authors treated selected patients who had stage IV, V, or VI osteonecrosis with uncemented, porous-coated components on the femoral side. These stems are designed for bone ingrowth, with the goal of attaining a more viable and permanent interlocking bone between the implant and host bone. This article presents the necessary surgical principles and techniques for biologic fixation arthroplasty and reports the early results that have been obtained. PMID:4058902

Engh, C A; Gloss, F E; Bobyn, J D



Suture suspension arthroplasty technique for basal joint arthritis reconstruction.  


Numerous techniques have been developed to address thumb basal joint arthritis. Many techniques include trapeziectomy with ligament reconstruction, most commonly performed by sacrificing a tendon that is used for ligament reconstruction and stabilization of the first metacarpal, with or without pin fixation. Harvesting a tendon for use in basal joint reconstruction is time-consuming and not without potential complications. Redirecting tendons via drill holes or anchoring tendons via suture anchors adds additional morbidity and time to the operative procedures. The authors introduce a novel technique of basal joint reconstruction, employing suture suspension for maintenance of joint arthroplasty space and stabilization of the base of the first metacarpal. PMID:19956040

DelSignore, Jeanne L; Accardi, Kimberly Z



Tourniquet use in total knee arthroplasty: a meta-analysis  

Microsoft Academic Search

Purpose  The use of an intraoperative tourniquet for total knee arthroplasty (TKA) is a common practice. However, the effectiveness\\u000a and safety are still questionable. A systematic review was conducted to examine that whether using a tourniquet in TKA was\\u000a effective without increasing the risk of complications.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  A comprehensive literature search was done in PubMed Medicine, Embase, and other internet database. The

Ta-Wei Tai; Chii-Jeng Lin; I-Ming Jou; Chih-Wei Chang; Kuo-An Lai; Chyun-Yu Yang



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


One-stage reimplantation for infected total knee arthroplasty.  


One-stage reimplantation for the salvage of infected total knee arthroplasty in 18 patients was reviewed at an average follow-up of five years. There had been one recurrence and one new infection, both in rheumatoid patients with another focus of infection. In four other patients the clinical result was impaired by pain after walking (2) and limited flexion (2). Our results suggest that one-stage reimplantation is a reasonably reliable procedure for the management of a loose infected prosthesis. PMID:1732271

Göksan, S B; Freeman, M A



Squeaking in Metal-on-Metal Hip Resurfacing Arthroplasties  

Microsoft Academic Search

Background  While most reports of audible squeaking in total hip arthroplasty (THA) have focused on ceramic bearings, squeaking can occur\\u000a in metal-on-metal bearings and may be an important clinical complication to consider during patient followup.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  We retrospectively identified 10 patients with squeaking metal-on-metal hip resurfacings.\\u000a \\u000a \\u000a \\u000a Methods  This study reports acetabular inclination angles and patient satisfaction, and describes two patients with squeaking resurfacings:

Christina Esposito; William L. Walter; Pat Campbell; Anne Roques



Revision Total Knee Arthroplasty Infection: Incidence and Predictors  

Microsoft Academic Search

Background  Deep infection remains one of the most devastating and costly complications after total knee arthroplasty (TKA). The risk\\u000a of deep infection after revision TKA is reportedly greater than that for primary TKA; however, we do not know the exact incidence\\u000a of infection after revision TKA.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  We determined the incidence of infection after revision, the type of microorganisms involved and TKA,

S. M. Javad Mortazavi; Justin Schwartzenberger; Matthew S. Austin; James J. Purtill; Javad Parvizi



Technical Challenges of Total Knee Arthroplasty in Skeletal Dysplasia  

Microsoft Academic Search

Background  Total knee arthroplasty (TKA) in patients with skeletal dysplasias is particularly challenging as a result of the anatomic\\u000a variances and substantial bony deformities. Little has been written regarding technical considerations that should be made\\u000a when performing TKA in skeletal dysplasia.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  We describe special operative considerations that must be made when performing TKA on patients with skeletal dysplasia, including\\u000a implant selection

Raymond H. Kim; Giles R. Scuderi; Douglas A. Dennis; Steven W. Nakano



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


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; Park, Jong-Seok; Song, Ui-Seoub; Kim, Woo-Jong; Suh, You-Sung



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


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



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.

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



Bile-acid-mediated decrease in endoplasmic reticulum stress: a potential contributor to the metabolic benefits of ileal interposition surgery in UCD-T2DM rats  

PubMed Central

SUMMARY Post-operative increases in circulating bile acids have been suggested to contribute to the metabolic benefits of bariatric surgery; however, their mechanistic contributions remain undefined. We have previously reported that ileal interposition (IT) surgery delays the onset of type 2 diabetes in UCD-T2DM rats and increases circulating bile acids, independently of effects on energy intake or body weight. Therefore, we investigated potential mechanisms by which post-operative increases in circulating bile acids improve glucose homeostasis after IT surgery. IT, sham or no surgery was performed on 2-month-old weight-matched male UCD-T2DM rats. Animals underwent an oral fat tolerance test (OFTT) and serial oral glucose tolerance tests (OGTT). Tissues were collected at 1.5 and 4.5 months after surgery. Cell culture models were used to investigate interactions between bile acids and ER stress. IT-operated animals exhibited marked improvements in glucose and lipid metabolism, with concurrent increases in postprandial glucagon-like peptide-1 (GLP-1) secretion during the OFTT and OGTTs, independently of food intake and body weight. Measurement of circulating bile acid profiles revealed increases in circulating total bile acids in IT-operated animals, with a preferential increase in circulating cholic acid concentrations. Gut microbial populations were assessed as potential contributors to the increases in circulating bile acid concentrations, which revealed proportional increases in Gammaproteobacteria in IT-operated animals. Furthermore, IT surgery decreased all three sub-arms of ER stress signaling in liver, adipose and pancreas tissues. Amelioration of ER stress coincided with improved insulin signaling and preservation of ?-cell mass in IT-operated animals. Incubation of hepatocyte, adipocyte and ?-cell lines with cholic acid decreased ER stress. These results suggest that postoperative increases in circulating cholic acid concentration contribute to improvements in glucose homeostasis after IT surgery by ameliorating ER stress.

Cummings, Bethany P.; Bettaieb, Ahmed; Graham, James L.; Kim, Jaehyoung; Ma, Fangrui; Shibata, Noreene; Stanhope, Kimber L.; Giulivi, Cecilia; Hansen, Frederik; Jelsing, Jacob; Vrang, Niels; Kowala, Mark; Chouinard, Michael L.; Haj, Fawaz G.; Havel, Peter J.



Health-related quality of life in veterans with prevalent total knee arthroplasty and total hip arthroplasty  

PubMed Central

Objective. To study the HRQOL in veterans with prevalent total knee arthroplasty (TKA) or total hip arthroplasty (THA) and compare them with age- and gender-matched US population and control veteran population without these procedures. Methods. A cohort study and cross-sectional survey on veterans obtained demographics and HRQOL with Short-Form 36 for veterans (SF-36V). Veterans were categorized into: primary TKA; primary THA; combination group (?1 primary and/or any revision TKA/THA); and control population (no THA/TKA). Multivariable regression compared the physical and mental component summary scores (PCS and MCS scores, respectively) in each group. Results. Response rate was 58% (40 508/70 334): 531 with TKA, 254 with THA, 461 constituted the combination and 39 262, the control group. Mean PCS scores in veterans with THA, TKA, and combination group were 2 s.d. lower than the US mean (29.5 ± 0.8; 30.1 ± 1.1 and 27.1 ± 0.8). MCS scores were similar to the US mean (47.3 ± 0.9; 49.1 ± 1.2 and 45.6 ± 0.9). Compared with controls, significantly more veterans in TKA, THA or combination groups had multivariable-adjusted PCS ? 30 (55, 64, 71 and 76%; P < 0.0001); similar proportion had MCS ? 30 (15, 12, 8 and 16%; P = 0.29); and mean scores on SF-36 physical domains (P ? 0.0011), but not mental/emotional domains (P ? 0.01) were statistically and clinically lower. Conclusions. Profound physical HRQOL deficits exist in veterans with TKA/THA and in combination group compared with age- and gender-matched general US population and with veteran controls. In these groups, these deficits are not attributable to differences in sociodemographics, comorbidity and healthcare access/utilization. Arthroplasty status may be a surrogate for poorer HRQOL and worse outcomes. Future studies are indicated to determine HRQOL deficit causes and interventions to improve HRQOL in patients with arthroplasty.

Sloan, J. A.



Optimized functional femoral rotation in navigated total knee arthroplasty considering ligament tension.  


Femoral malrotation in total knee arthroplasty is correlated to an increased number of revisions. Anatomic landmarks such as Whiteside line, posterior condyle axis and transepicondylar axis are used for determining femoral component rotation. The femoral rotation achieved with the anatomical landmarks is compared to the femoral rotation achieved by a navigated ligament tension-based tibia-first technique. Ninety-three consecutive patients with gonarthritis were prospectively enrolled. Intraoperatively the anatomical landmarks for femoral rotation and the achieved femoral rotation using a navigated tension-based tibia-first technique were determined and stored for further comparison. A pre- and postoperative functional diagram displaying the extension and flexion and varus or valgus positions was also part of the evaluation. Using anatomical landmarks the rotational errors ranged from 12.2° of internal rotation to 15.5° of external rotation from parallel to the tibial resection surface at 90° flexion. A statistical significant improved femoral rotation was achieved using the ligament tension-based method with a rotational error ranged from 3.0° of internal rotation to 2.4° of external rotation. The functional analyses demonstrated statistical significant lower varus/valgus deviations within the flexion range and an improved maximum varus deviation at 90° flexion using the ligament tension-based method. Compared to the anatomical landmarks a balanced, almost parallel flexion gap was achieved using a navigation technique taking the ligament tension of the knee joint into account. As a result the improved femoral rotation was demonstrated by the functional evaluation. Unilateral overloading of the polyethylene inlay and unilateral instability can thus be avoided. PMID:20061156

Walde, T A; Bussert, J; Sehmisch, S; Balcarek, P; Stürmer, K M; Walde, H J; Frosch, K H



Glove perforation and contamination in primary total hip arthroplasty.  


We conducted a randomised, controlled trial to determine whether changing gloves at specified intervals can reduce the incidence of glove perforation and contamination in total hip arthroplasty. A total of 50 patients were included in the study. In the study group (25 patients), gloves were changed at 20-minute intervals or prior to cementation. In the control group (25 patients), gloves were changed prior to cementation. In addition, gloves were changed in both groups whenever there was a visible puncture. Only outer gloves were investigated. Contamination was tested by impression of gloved fingers on blood agar and culture plates were subsequently incubated at 37 degrees C for 48 hours. The number of colonies and types of organisms were recorded. Glove perforation was assessed using the water test. The incidence of perforation and contamination was significantly lower in the study group compared with the control group. Changing gloves at regular intervals is an effective way to decrease the incidence of glove perforation and bacterial contamination during total hip arthroplasty. PMID:15795210

Al-Maiyah, M; Bajwa, A; Mackenney, P; Port, A; Gregg, P J; Hill, D; Finn, P



The first 50 years of total hip arthroplasty: lessons learned.  


Fifty years have passed since the first total hip arthroplasty of the modern era was performed. At this, the vantage point, it is reasonable to review these five decades, inquiring behind the single dominating observation that, in its current form, this operation is one of the most successful of all surgical procedures for the management of end-stage human disease. What are the generic lessons that can be derived from the experience? Succinctly, five major observations appear valuable. They are "skunk works," "Pasteur's motto," "the totally unexpected," "research solutions," and "the role of alternatives." "Skunk works," an industrial management term, might be characterized as an innovative endeavor that is offline and off-budget resulting from the relentless pursuit of a vivid dream by creative zealots who eschew defeat. Pasteur's motto dealt with serendipity, which was crucial to total hip arthroplasty progress. The totally unexpected is represented by an entirely new manmade disease, "periprosthetic osteolysis." The research solutions are represented by the complex, sophisticated contemporary research that has unraveled periprosthetic osteolysis and suggested modes of correction. Finally, the application of "alternatives" has characterized major progress. Importantly, these, or similar generic observations, may provide insights into important progress in the future. PMID:18982399

Harris, William H



The First 50 Years of Total Hip Arthroplasty: Lessons Learned  

PubMed Central

Fifty years have passed since the first total hip arthroplasty of the modern era was performed. At this, the vantage point, it is reasonable to review these five decades, inquiring behind the single dominating observation that, in its current form, this operation is one of the most successful of all surgical procedures for the management of end-stage human disease. What are the generic lessons that can be derived from the experience? Succinctly, five major observations appear valuable. They are “skunk works,” “Pasteur’s motto,” “the totally unexpected,” “research solutions,” and “the role of alternatives.” “Skunk works,” an industrial management term, might be characterized as an innovative endeavor that is offline and off-budget resulting from the relentless pursuit of a vivid dream by creative zealots who eschew defeat. Pasteur’s motto dealt with serendipity, which was crucial to total hip arthroplasty progress. The totally unexpected is represented by an entirely new manmade disease, “periprosthetic osteolysis.” The research solutions are represented by the complex, sophisticated contemporary research that has unraveled periprosthetic osteolysis and suggested modes of correction. Finally, the application of “alternatives” has characterized major progress. Importantly, these, or similar generic observations, may provide insights into important progress in the future.



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


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



Outcomes of total knee replacement after patellofemoral arthroplasty.  


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



Management of the Deficient Patella in Revision Total Knee Arthroplasty  

PubMed Central

There are a number of options available to manage the patella when revising a failed total knee arthroplasty. If the previous patellar component is well-fixed, undamaged, not worn, and compatible with the femoral revision component, then it can be retained. When a patellar component necessitates revision and is removed with adequate remaining patellar bone stock, an onlay-type all-polyethylene cemented implant can be used. Management of the patella with severe bony deficiency remains controversial. Treatment options for the severely deficient patella include the use of a cemented all-polyethylene biconvex patellar prosthesis, patellar bone grafting and augmentation, patellar resection arthroplasty (patelloplasty), performing a gull-wing osteotomy, patellectomy, or the use of newer technology such as a tantalum (trabecular metal) patellar prosthesis. Severe patellar bone deficiency is a challenging situation because restoration of the extensor mechanism, proper patellar tracking, and satisfactory anatomic relationships with the femoral and tibial components are critical for an optimal clinical outcome. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Kraay, Matthew J.; Conroy-Smith, Patricia A.; Goldberg, Victor M.



High frequency failure of the Moje thumb carpometacarpal joint arthroplasty.  


Arthroplasty is one of several options for treating symptomatic osteoarthritis of the thumb carpometacarpal joint. There are various hemi- and total arthroplasties available on the market. We report our experience of treating 12 patients with the Moje Acamo CMC1 prosthesis. We reviewed all the patients at a mean of 50 months postoperatively. All patients presented with loosening, migration or tilting of one or both implant components. Nine patients were symptomatic enough to warrant revision surgery with removal of the implant leaving a pseudarthrosis. At the last follow-up, five patients (42%) had already received revision surgery. All patients still possessing an implant showed progressive signs of implant loosening, although some of them had no symptoms. In order to assess their overall disadvantage compared with patients treated by primary trapeziectomy, the outcomes of these two groups were compared (matched pairs). The outcomes after revision surgery were comparable with those of primary trapeziectomy. We no longer use the Moje Acamo CMC1 implant and recommend that patients who have received this implant should be monitored carefully both clinically and radiologically. PMID:22791610

Kaszap, B; Daecke, W; Jung, M



Treatment of Periprosthetic Femoral Fractures in Hip Arthroplasty  

PubMed Central

Background We analyzed the radiological and clinical results of our study subjects according to the management algorithm of the Vancouver classification system for the treatment of periprosthetic femoral fractures in hip arthroplasty. Methods We retrospectively reviewed 18 hips with postoperative periprosthetic femoral fractures. The average follow-up was 49 months. The fracture type was determined based on the Vancouver classification system. The management algorithm of the Vancouver classification system was generally applied, but it was modified in some cases according to the surgeon's decision. At the final follow-up, we assessed the radiological results using Beals and Tower's criteria. The functional results were also evaluated by calculating the Harris hip scores. Results Seventeen of 18 cases (94.4%) achieved primary union at an average of 25.5 weeks. The mean Harris hip score was 92. There was 1 case of nonunion, which was a type C fracture after cemented total hip arthroplasty, and this required a strut allograft. Subsidence was noted in 1 case, but the fracture was united despite the subsidence. There was no other complication. Conclusions Although we somewhat veered out of the management algorithm of the Vancouver classification system, the customized treatment, with considering the stability of the femoral stem and the configuration of the fracture, showed favorable overall results.

Park, Sung Ki; Kim, Young Gun



Hip arthroplasty after failed fixation of trochanteric and subtrochanteric fractures  

PubMed Central

Background and purpose Hip arthroplasty is an option for elderly patients with osteoporosis for the treatment of failure after fixation of trochanteric and subtrochanteric fractures, either as a total hip arthroplasty (THA) or as a hemiarthroplasty (HA). We analyzed the reoperation rate and risk factors for reoperation in a consecutive series of patients. Methods All patients (n = 88) operated from 1999 to 2006 with a THA (n = 63) or an HA (n = 25) due to failure of fixation of a trochanteric fracture (n = 63) or subtrochanteric fracture (n = 25) were included. Background data were collected from the patient records. A search was performed in the national registry of the Swedish National Board of Health and Welfare in order to find information on all reoperations. The follow-up time was 5–11 years. Results The reoperation rate was 16% (14/88 hips). A periprosthetic fracture occurred in 6 patients, a deep prosthetic infection in 5 patients, and a dislocation of the prosthesis in 3 patients. Standard-length femoral stems had an increased risk of reoperation (11/47) compared to long stems (3/41) (HR = 4, 95% CI: 1.0–13; p = 0.06). Interpretation The high reoperation rate reflects the complexity of the surgery. Using long femoral stems that bridge previous holes and defects may be one way to reduce the risk for reoperation.



Tendon suspension sling arthroplasty for thumb trapeziometacarpal arthritis.  


Forty consecutive tendon suspension sling arthroplasties for relief of pantrapezial osteoarthritis in 38 patients were reviewed. The procedure consists of excision of the trapezium and reconstitution of the tethering action of the first intermetacarpal and the palmar oblique carpometacarpal ligaments; 50% of the distally based flexor carpi radialis tendon is used. A double figure-eight sling suspends the first metacarpal securely, followed by distal advancement of the abductor pollicis longus to tighten the sling and palmarly abduct the thumb ray. The technique resulted in relief of pain, preservation of strength, maintenance of a normally contoured first web space, and functional carpometacarpal range of motion. Procedures were performed over a 4-year period (1986 to 1990), with an average follow-up of 21 months. At final follow-up, 85% of the patients had minimal symptoms; key pinch and grip strengths measured 76% and 81% of the contralateral uninvolved side, respectively. The logic of the mechanical design of the procedure and encouraging subjective and objective follow-up at 4 years make the technique of tendon suspension sling arthroplasty an attractive alternative to existing procedures for the surgical management of recalcitrant and disabling osteoarthritis of the basilar thumb joint. PMID:1748769

Kleinman, W B; Eckenrode, J F



Perichondrial arthroplasty. A clinical study in twenty-six patients.  


26 patients with painful and/or rigid small joints of the extremities have undergone surgery by a new arthroplasty method, utilizing the cartilaginous potential of the perichondrium demonstrated earlier in animal experiments. Perichondrium from the rib has been grafted to the articular surfaces of the affected joint after removal of the remaining ordinary articular cartilage. In 12 cases the joint disease was a sequela after trauma--either fracture involving the joint surfaces, or an open joint injury complicated by a purulent arthritis. In 6 cases there was an idiopathic degenerative joint disease and in 5 the arthritis was of rheumatic origin. In a further 3 cases the indications for operation were various. The follow-up period varied between 3 and 41 months. 13 patients classified as excellent regained range of motion and power and had no pain either at rest or at work. In 3 cases range of motion and power improved, but there was still some pain in the affected joint at work. Ten cases were not improved by the perichondrial arthroplasty and possible reasons for this are discussed. The results indicate that it is possible to restore joint function using free autologous perichondrial grafts from the rib. PMID:7384759

Engkvist, O; Johansson, S H



Small Stem Total Hip Arthroplasty in Hypoplasia of the Femur  

PubMed Central

Total hip arthroplasty in hypoplastic femurs is technically difficult and the incidence of complications and aseptic loosening is relatively high. Cemented, uncemented, off-the-shelf, and custom-made stems all have been advocated in these cases. From 1978 to 1997, we performed 86 total hip arthroplasties in 77 patients with a hypoplastic femur using a cemented, off-the-shelf, small, curved, cobalt-chromium stem. We hypothesized results equaled those of the identical but larger-sized stems in normal-sized femora which were used as comparisons. Clinical and radiographic evaluations were performed. Minimum followup was 4.2 years (mean, 12 years; range, 4.2–20.3 years); mean Harris hip score was 88, and mean hip flexion was 104°. Six stems were revised: four because of aseptic loosening, one after a femoral fracture, and one because of malpositioning. Complications included one perforation and one fracture of the femur, one fracture, one nonunion of the greater trochanter, and one deep infection. Implant survivorship for all hips at 15 years with aseptic revision of the stem as the end point was 90% (confidence interval, 82–99) which equaled results of the larger stems. The small off-the-shelf cemented Weber stem has a high long-term survival and a low complication rate. Survival compares favorably with other small-sized total hip systems. Level of Evidence: Level III, therapeutic study, case-control.

Haverkamp, Daniel; Van der Vis, Harm M.; Besselaar, Philip P.; Marti, Rene K.



Should a Patients BMI Status be Used to Restrict Access to Total Hip and Knee Arthroplasty? Functional Outcomes of Arthroplasty Relative to BMI - Single Centre Retrospective Review  

PubMed Central

We reviewed the experience of a dedicated orthopaedic elective service to determine whether we could establish a BMI group where arthroplasty was no longer effective as assessed by the patient’s functional outcome. This was a prospective observational study with retrospective analysis of data collected on 1439 total hip arthroplasty, 934 total knee arthroplasty and 326 unicompartment knee arthroplasty patients. Functional scores (WOMAC, Oxford hip and knee scores and HAAS) were obtained preoperatively and at 12 months post op. Patients had their BMI recorded at the preoperative assessment and were divided into BMI groups (BMI<25, BMI 25-30, BMI 30-35 and BMI > 35). Patients with a BMI of ? 30 had significantly better functional scores at 12 months post op compared to those with a BMI of > 35. The absolute gain in functional scores from pre op to 12 months post op did not differ significantly between BMI groups, the only significant difference we found for absolute gain showed patients with a BMI of > 35 have a greater increase in HAAS scores following total hip arthroplasty compared to patients with a BMI of 30 or less (p = 0.0435). Our patients with higher BMI’s had worse preoperative and post operative functional scores but their benefit from surgery measured by the change in functional scores showed no difference compared to patients with lower BMI. We could find no reason on the basis of the 12-month results to limit surgery to obese patients because of an expected poorer functional outcome.

Lash, H.; Hooper, G.; Hooper, N.; Frampton, C.



Orthopaedic crossfire--can we justify unicondylar arthroplasty as a temporizing procedure? in the affirmative.  


In 1972, unicondylar knee arthroplasty (UKA) was introduced, along with total knee arthroplasty (TKA), as an option for managing gonarthrosis. Although the early clinical results with the first generation of implants were equivalent to those of total knee arthroplasty, little interest in UKA was sustained. If unicondylar arthroplasty is to realize a role in the management of degenerative arthritis, even as a temporizing procedure, the results must be predictable and reproducible. Patient satisfaction must be equivalent to or better than that of TKA. Finally, the conversion of UKA to TKA must be uncomplicated, avoiding complex reconstructive procedures and the use of revision implants. As documented in the literature, UKA achieves these goals. Therefore, we cannot only justify UKA as a temporizing procedure, but also as a definitive procedure with long-term results that are comparable to TKA for gonarthrosis. PMID:12068405

Engh, Gerard A



Proximal femoral osteotomy as an adjunct in cementless revision total hip arthroplasty.  


Cementless total hip replacement techniques are increasingly used in revision arthroplasty. A major challenge is to achieve implant stability in a femur distorted by a failed arthroplasty. Five patients with aseptic loosening of cemented primary or revision total hip replacements complicated by significant proximal femoral disease, four with marked angular deformity of the femur and one with a subtrochanteric nonunion, were treated successfully with cementless revision arthroplasty combined with proximal femoral osteotomy. At follow-up examination, all femoral and trochanteric osteotomies had healed and D'Aubigne and Postel scores for pain, function, and range of motion had improved. All porous prostheses demonstrated radiographic features consistent with bone ingrowth fixation. No progressive stress shielding has been observed. Concomitant femoral osteotomy to correct anatomic deformity, in association with cementless total hip arthroplasty, results in union of the osteotomy and restoration of hip function. PMID:3572412

Glassman, A H; Engh, C A; Bobyn, J D



New Hip, - Nursing Care of the Patient with the Total Hip Arthroplasty.  

National Technical Information Service (NTIS)

Describes how nursing care measures important in preoperative, postoperative, and discharge planning care of the total hip arthroplasty patient. These include prevention of the dislocation, occupied bed-making, patient transfer, and positioning and exerci...



The use of dual-mobility components in total hip arthroplasty.  


Dual-mobility hip components provide for an additional articular surface, with the goal of improving range of motion, jump distance (ie, vertical or inferior head displacement required for dislocation), and stability of the total hip arthroplasty. A large polyethylene head articulates with a polished metal acetabular component, and an additional smaller metal head is snap-fit within the polyethylene. New components have recently been released for use in North America. Although these devices are routinely used in some European centers for primary hip arthroplasty, their greatest utility may be to manage recurrent dislocation in the setting of revision hip arthroplasty. Several small retrospective series have shown satisfactory results for this indication at short- to midterm follow-up. Polyethylene wear and intraprosthetic dislocation are concerns, as is the lack of long-term data. Caution is thus advised in the routine use of dual-mobility components in primary and revision total hip arthroplasty. PMID:22855850

Lachiewicz, Paul F; Watters, Tyler Steven



Osteoporosis and orthopedic surgery: effect of bone health on total joint arthroplasty outcome.  


Osteoporosis is a common condition. As the population ages, more patients with osteoporosis will require orthopedic procedures, including arthroplasty. Adverse outcomes are more likely for patients with osteoporosis requiring orthopedic procedures, for example those with intraoperative fractures, periprosthetic osteolysis with implant migration, and postoperative periprosthetic fractures. Cemented prosthetic hip replacements may be more successful among patients with poor bone quality. Femoral neck fracture is a concern during hip resurfacing among patients with osteoporosis. Vitamin D deficiency is common among patients undergoing joint arthroplasty and the ideal vitamin D level for joint arthroplasty has yet to be determined. Both bisphosphonates and teriparatide may aide successful osteointegration among patients undergoing noncemented joint arthroplasty. Focusing on bone health perioperatively should result in better outcomes for orthopedic procedures. PMID:24085661

Russell, Linda A



Cementless large-head metal-on-metal total hip arthroplasty in patients younger than 60 years--a multicenter early result.  


Large-head metal-on-metal total hip arthroplasty has the theoretical advantages of less wear and better range of motion than traditional polyethylene bearings and seems to be a better choice for young and active patients. We conducted a retrospective study and reported the early results of using such prostheses in 59 patients (70 hips) with a mean age of 43.1 years (range, 23-59 years) at the time of surgery. Osteonecrosis of the femoral head accounted for most diagnoses. Harris Hip Scores and hip range of motion both significantly improved (p<0.001) at an average follow-up of 32.6 months (range, 24-48 months). Only one intraoperative calcar fissure was encountered, and it was fixated by cerclage wiring; there was no infection, dislocation, or osteolysis around either the cup or the stem at the latest follow-up. A postoperative gap in the acetabular component was noted in 24 hips, with a mean depth of 1.11 mm, but this was not correlated with the functional score (p=0.291). Transient thigh pain, which resolved after 6 months, was observed in six patients but was not related to either the postoperative gap or cup inclination (p=1.000 and p=0.664, respectively). All patients resumed their original jobs and recreational activities with little discomfort. Thus far, large-head metal-on-metal total hip arthroplasty has shown excellent early results. The long-term results and the effects of metal debris and potentially elevated serum metal ion levels require further observation. PMID:22226059

Wu, Po-Ting; Wang, Chih-Jen; Yen, Cheng-Yo; Jian, Ji-Shen; Lai, Kuo-An



Failure of a metal-on-metal total hip arthroplasty from progressive osteolysis  

Microsoft Academic Search

Ultra-high-molecular weight polyethylene (UHMWPE) wear, debris-induced osteolysis is a frequent cause of failure of total hip arthroplasty. Metal-on-metal total hip arthroplasty eliminates the generation of UHMWPE particulate debris. Although the volumetric wear of a metal-on-metal articulation may be lower than a metal-UHMWPE articulation, the number of particles may be higher. Osteolysis can develop in response to metallic and UHMWPE debris.

Catherine Klapperich; Jove Graham; Lisa Pruitt; Michael D. Ries



Three-in-One Nerve Block with Different Concentrations of Bupivacaine in Total Knee Arthroplasty  

Microsoft Academic Search

Pain after total knee arthroplasty may be severe and lead to adverse outcomes. Using 2 concentrations of bupivacaine, we investigated 3-in-1 nerve block's effect on pain control, narcotic use, sedation, and patient satisfaction. One hundred five patients undergoing unilateral total knee arthroplasty were randomized into 3 groups: low-dose or high-dose bupivacaine or placebo. Ninety-nine patients completed the study. Three-in-1 nerve

Zheng Xie; Waqas Hussain; Thomas W. Cutter; Jeffrey L. Apfelbaum; Melinda L. Drum; David W. Manning


Effects of acetabular component orientation on dislocation propensity for small-head-size total hip arthroplasty  

Microsoft Academic Search

Objective. Examine the role of surgical orientation of the acetabular cup on posterior dislocation propensity for small-head-size total hip arthroplasty.Design. A finite element model of a widely used total hip arthroplasty system was examined for peak resisting moment and range-of-motion prior to impingement, as well as prior to onset of posterior dislocation. Acetabular component surgical orientation was varied.Background. Dislocation is

Mark E Nadzadi; Douglas R Pedersen; John J Callaghan; Thomas D Brown



The Biomet Bi-Metric Total Hip Arthroplasty and Universal Acetabular Cup  

Microsoft Academic Search

We report on the medium-term results of the Bi-Metric (Biomet UK Ltd, Bridgend, UK) uncemented total hip arthroplasty system used with the Universal acetabular cup and polyethylene liner secured with the Ringloc (Biomet UK Ltd) mechanism. Fifty-eight total hip arthroplasties in 49 patients (mean age at implantation, 57.1 years) were identified, with 45 hips followed up at a mean of

David Llewellyn Isaac; Justin Forder; Andrew D. Skyrme; Stephen E. James



DEXA evaluation of total hip arthroplasty with neck-preserving technique: 4-year follow-up  

Microsoft Academic Search

Periprosthetic bone remodeling, and its evaluation, are the keys of long-term survival of cementless total hip arthroplasty. Dual energy X-ray absorptiometry (DEXA) is the most accurate method to measure bone mineral density, evaluating the effects of bone-prosthesis interactions. We studied, 4 years after implantation, 10 patients who underwent total hip arthroplasty with the CFP prosthetic stem and TOP acetabular cup

F. Biggi; F. Franchin; R. Lovato; F. Pipino



Tibial plateau stress fracture after unicondylar knee arthroplasty using a navigation system: two case reports  

Microsoft Academic Search

Satisfactory alignments of components in total knee arthroplasty have been reported since the introduction of navigation systems.\\u000a And thus, such techniques have been introduced for minimally invasive unicondylar knee arthroplasty (UKA). Several intraoperative\\u000a fractures of the tibial plateau have been reported in association with minimally invasive UKA and some stress fractures of\\u000a tibial plateau associated with design of instrument have

Jong Keun Seon; Eun Kyoo Song; Taek Rim Yoon; Hyoung Yeon Seo; Sang Gwon Cho



Operative treatment of distal femoral fractures above total knee arthroplasty with the indirect reduction technique  

Microsoft Academic Search

The complication rate of conventional plate osteosynthesis (CPO) of periprosthetic femoral fractures above total knee arthroplasties (TKA) is high. Indirect reduction techniques were introduced to reduce surgical dissection at the fracture site.Twenty-one patients (4 men and 17 women) with femoral fractures above well-fixed total knee arthroplasties were consecutively treated with the indirect reduction technique. AO\\/ASIF (Arbeitsgemeinschaft für Osteosynthesefragen\\/Association for the

Klaus Kolb; Heiko Koller; Ingo Lorenz; Ulrich Holz; Frank Marx; Paul Grützner; Werner Kolb



Small Increase of Actual Physical Activity 6 Months After Total Hip or Knee Arthroplasty  

Microsoft Academic Search

Limitation in daily physical activity is one of the reasons for total hip arthroplasty (THA) or total knee arthroplasty (TKA).\\u000a However, studies of the effects of THA or TKA generally do not determine actual daily activity as part of physical functioning.\\u000a We determined the effect of THA or TKA on patients’ actual physical activity and body function (pain, stiffness), capacity

Ingrid B. de Groot; Hans J. Bussmann; Henk J. Stam; Jan A. Verhaar



The case for the metal-backed glenoid design in total anatomical shoulder arthroplasty  

Microsoft Academic Search

After 38 years of unchallenged reign of cemented full polyethylene glenoid implants, the main problem of anatomical shoulder\\u000a arthroplasty is still glenoid loosening, also the main cause of failure. A certain concern regarding uncemented metal back\\u000a components in total anatomical shoulder arthroplasty has developed, due to problems evoked in the literature. This work is\\u000a a comprehensive bibliographical review of the different

Denis C. KatzP; P. Sauzières; P. Valenti; J. Kany


Etidronate does not suppress periprosthetic bone loss following cemented hip arthroplasty  

Microsoft Academic Search

Periprosthetic bone loss after arthroplasty may threaten prosthesis survival. The current study investigated the effect of\\u000a etidronate therapy on periprosthetic, contralateral hip, and spine bone mineral density (BMD) in a one-year, prospective,\\u000a randomized, double-blind study on 46 patients after cemented hip arthroplasty. BMD was measured with dual-energy X-ray absorptiometry\\u000a (DXA). There were no significant differences between mean BMD measurements of

S. K. Fokter; R. Komadina; A. Repše-Fokter; S. A. Yerby; A. Kocijan?i?; J. Marc



Periprosthetic Malignancy as a Mode of Failure in Total Hip Arthroplasty  

Microsoft Academic Search

The presence of periprosthetic malignancy in proximity to arthroplasty implants has been infrequently reported. We present the clinical, radiographic, and pathological features of three patients in whom loosening and failure of total hip arthroplasties occurred secondary to malignant infiltration. They consisted of a 66-year-old man with the first presentation of metastatic gastric carcinoma as a periacetabular lytic lesion, a 64-year-old

Kieran O'Shea; Stephen R. Kearns; Anya Blaney; Paraic Murray; Hugh A. Smyth; John P. McElwain



Metal-on-metal surface arthroplasty with a cemented femoral component  

Microsoft Academic Search

Forty-two McMinn metal-on-metal surface arthroplasties were implanted in 23 males and 16 females, average age 47.5 years old. The overall survivorship at 7 years was 79%; with any reoperation surgery as endpoint, 80%; and 93%; with aseptic loosening of the socket and femoral component, respectively. The average Surface Arthroplasty Risk Index of patients who had failed or were at risk

Paul E. Beaulé; Michel Le Duff; Pat Campbell; Fred J. Dorey; Sang Hyun Park; Harlan C. Amstutz



Do Large Heads Enhance Stability and Restore Native Anatomy in Primary Total Hip Arthroplasty?  

Microsoft Academic Search

Background  Dislocation remains a serious complication in hip arthroplasty. Resurfacing proponents tout anatomic femoral head restoration\\u000a as an advantage over total hip arthroplasty. However, advances in bearings have expanded prosthetic head options from traditional\\u000a sizes of 22, 26, 28, and 32 mm to diameters as large as 60 mm. Large heads reportedly enhance stability owing to increased\\u000a range of motion before impingement and

Adolph V. Lombardi Jr; Michael D. Skeels; Keith R. Berend; Joanne B. Adams; Orlando J. Franchi



Animal-Associated Bacteria, Erysipelotrix rhusiopathiae, as the Cause of Infection in a Total Hip Arthroplasty  

Microsoft Academic Search

Invasive infection with animal-associated bacteria, Erysipelotrix rhusiopathiae, is unusual and has, to our knowledge, never been described as the cause of infected total hip arthroplasty. We describe how an infected total hip arthroplasty caused by these bacteria is eradicated using standard surgical and antibiotic treatment. Before 2-stage revision surgery, the patient had persistent groin pain, elevated C-reactive protein, radiographic periprosthetic

Andres Troelsen; Jens K. Møller; Lars Bolvig; Thomas Prynø; Lisbeth N. Pedersen; Kjeld Søballe



Dabigatran Etexilate: Pivotal Trials for Venous Thromboembolism Prophylaxis After Hip or Knee Arthroplasty  

Microsoft Academic Search

Dabigatran etexilate, an oral direct thrombin inhibitor, was investigated in 3 large phase III trials for the prevention of venous thromboembolism (VTE) after total hip arthroplasty (RE-NOVATE, N = 3494) or total knee arthroplasty (RE-MODEL, N = 2076 and RE-MOBILIZE, N = 2615). RE-NOVATE and RE-MODEL were conducted mainly in Europe, and RE-MOBILIZE was conducted predominantly in the United States

Bengt I. Eriksson; Richard J. Friedman



Gaps below strange star crusts  

SciTech Connect

The gap caused by a strong electric field between the quark surface and nuclear crust of a strange star is studied in an improved model including gravity and pressure as well as electrostatic forces. The transition from gap to crust is followed in detail. The properties of the gap are investigated for a wide range of parameters assuming both color-flavor locked and noncolor-flavor locked strange star cores. The maximally allowed crust density is generally lower than that of neutron drip. Finite temperature is shown to increase the gap width, but the effect is significant only at extreme temperatures. Analytical approximations are derived and shown to provide useful fits to the numerical results.

Stejner, Morten; Madsen, Jes [Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C (Denmark)



Plenary 1 – Gaps in Oncology

The first plenary of the EPEC-O (Education in Palliative and End-of-Life Care for Oncology) Self-Study Original Version provides background for the curriculum and identifies gaps in current and desired comprehensive cancer care.


Gap Junctions and Heart Development  

Microsoft Academic Search

\\u000a The function of gap junctions in propagation of the cardiac action potential is one of the best characterized roles for intercellular\\u000a communication. Comprehending the part played by cell-to-cell dialogue in embryological processes, including development of\\u000a the heart, has proven to be a more complex problem. Nonetheless, research at the conjunction of cardiac development and gap\\u000a junctions is a diverse and

Robert G. Gourdie; Wanda H. Litchenberg; Leonard M. Eisenberg


The Gender Gap in Ideology  

Microsoft Academic Search

Over the past few decades, a gender gap has emerged in the mass public in ideological self-placement. While most men and women\\u000a moved in the conservative direction, another segment of women retained their liberal self-identifications. A gender gap also\\u000a exists in how men and women define their ideology. Which issues are linked to ideological identities is conditioned by gender\\u000a and

Barbara Norrander; Clyde Wilcox



Eight electrode optical readout gap  


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.



A Phase 2b Study of DU-176b, Prevention of Venous Thromboembolism in Patients After Total Hip Arthroplasty

Anticoagulants; Venous Thromboembolism; Thromboembolism; Thrombosis; Enoxaparin Sodium; Embolism and Thrombosis; Deep Vein Thrombosis; DU-176b; Edoxaban; Factor Xa; Oral; Arthroplasty, Replacement, Hip



Pneumatic gap sensor and method  

SciTech Connect

This patent describes in a casting system which including an apparatus for monitoring the gap between a casting nozzle and a casting surface of a substrate during casting of molten material, wherein the molten material is provided through a channel of the casting nozzle for casting onto the casting surface of the substrate for solidification. It comprises: a pneumatic gap mounted at least partially within a cavity in the casting nozzle adjacent the channel and having a sensor face located within the gap between the nozzle and the casting surface of the substrate, means for supply gas under predetermined pressure to the inlet orifice; and means for measuring the pressure of the gas within the sensor chamber during casting procedures, whereby relative changes in the gap can be determined by corresponding changes in the measured pressure. This patent also describes a method for monitoring the gap between a casting nozzle and a casting surface of a substrate for continuous casting of molten material. It comprises: providing a casting nozzle with a channel for directing the flow of molten material, locating the nozzle and the casting surface is proximity with one another and having a predetermined gap there-between, and dressing the sensor face to correspond in conformation to the casting surface and to adjust the predetermined distance as desired; providing a molten material to the nozzle for casting onto and casting surface; supplying gas at a predetermined pressure to the inlet orifice of the sensor during casting procedures.

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



Highly cross-linked polyethylene in total knee arthroplasty: in the affirmative.  


Polyethylene bearing failure has been cited as one of the leading causes of knee arthroplasty revision surgery. In 1998, highly cross-linked polyethylene was introduced for clinical use in total hip arthroplasty. Altered mechanical properties in first-generation highly cross-linked polyethylene did exhibit clinical failures, such as post fractures in total knee arthroplasty. Remelting alters the integrity of polyethylene. Some approaches to mitigate this include mechanical deformation, vitamin E incorporation, and sequential irradiation and annealing. Forces and stresses in total knee arthroplasty differ substantially from the wear mechanisms and forces seen in total hip arthroplasty. There is now considerable interest in the clinical use of highly cross-linked polyethylene for the knee. The use of sequentially annealed, highly cross-linked polyethylene, based on bench top data, appears to be promising for use in total knee arthroplasty. One should be aware that all highly cross-linked polyethylenes are not manufactured, nor processed, in the same manner. Marked and significant differences may exist between products. PMID:18701237

Jacofsky, David J



Radiologic review of total elbow, radial head, and capitellar resurfacing arthroplasty.  


The use of metal and pyrolytic carbon radial head implants, capitellar resurfacing, and total elbow arthroplasty has become common in contemporary orthopedic surgery practice. The goal of total elbow arthroplasty is to decrease pain and restore an acceptable range of motion to the elbow joint. Rheumatoid arthritis is the primary indication for total elbow arthroplasty; newer indications include primary or posttraumatic osteoarthritis, fracture nonunion, acute comminuted fractures of the elbow, and postoperative resection of a neoplasm. Unlike total elbow arthroplasty, radial head replacement is most commonly performed in patients with trauma. Radial head fractures account for 33% of all elbow fractures in adults and are often associated with ligament disruption and valgus instability at the elbow. The goals of capitellar resurfacing arthroplasty include prevention of secondary osteoarthritis of the radiocapitellar joint and erosion in patients with radial head arthroplasty. Effective postoperative radiologic assessment of these different types of elbow reconstructions requires an understanding of their basic component design, physiologic purpose, and normal postoperative appearance, as well as the appearance of complications. Radiologists may have little training and experience with these new orthopedic devices. PMID:22236898

Petscavage, Jonelle M; Ha, Alice S; Chew, Felix S


International Classification of Functioning, Disability and Health (ICF) Core Sets for osteoarthritis. A useful tool in the follow-up of patients after joint arthroplasty  

Microsoft Academic Search

Aim. The first aim of this study was to verify the applic- ability of the International Classification of Functioning Disability and Health (ICF) core set for osteoarthritis (OA) as an outcome tool after the total hip arthroplasty (THA) and total knee arthroplasty (TKA), in order to follow the changes of the profile of functioning after joint arthroplasty. Methods. Seventy-two OA



Achieving ligament stability and correct rotational alignment of the femur in knee arthroplasty: a study using the Medial Pivot knee.  


In a series of 90 Medial Pivot arthroplasties rotational alignment of the femur was achieved by provisionally reconstructing the lateral side of the joint and tensioning the medial side with feeler gauges. Axial CT scans were employed to measure the rotational alignment relative to surgical epicondylar axis. In valgus knees the cutting block was externally rotated to adjust for posterolateral bone loss. The mean rotational alignment of the femur was 0.6 degrees of external rotation (S.D. 1.3, range 3 degrees of ER to 4 degrees of IR). The mean laxity of the medial ligament was 1 mm in flexion (SD 1, range 0-5 mm) and 0.5 mm in flexion (S.D. 0.5, range 0-2 mm) In those knees in which the medial ligament had been released the CT alignment was perfect, but when internally rotated against the hip 3-4 mm of gapping was noted. In valgus knees the mean rotation of the femoral component was 0.8 degrees of internal rotation (S.D. 1.5, range 1 degrees of IR to 4 degrees of ER). In spite of externally rotating the cutting block there was still a tendency to internally rotate the femur in some knees. This simple technique achieves the two goals of ligament stability and correct rotational alignment in a high proportion of cases. It may be applicable to any instrument system which employs posterior referencing. PMID:15967668

Shakespeare, David; Kinzel, Vera; Ledger, Michael



Successful outcome of the Souter-Strathclyde elbow arthroplasty.  


This study describes a consecutive series of 68 primary Souter-Strathclyde elbow replacements performed in a predominantly rheumatoid population, compares survivorship and complication profile with published series, and analyzes factors associated with successful outcome. Survivorship at 10 years was 74%, with at least 5 years' follow-up in 25 prostheses and a satisfactory Mayo score in 92% of all 68 elbows. These results compare acceptably with those from specialized elbow units. Careful component selection with regard to joint stability and bony fixation are important factors in the successful outcome of the Souter-Strathclyde arthroplasty. Use of a long-stemmed prosthesis was associated with a significantly better outcome after intraoperative fracture, and revision to a linked articulation was the most reliable treatment for instability. PMID:15383813

Malone, Alexander A; Taylor, Andrew J N; Fyfe, Ian S


Total hip arthroplasty with porous metal cups following acetabular fracture.  


Total hip arthroplasty (THA) after acetabular fracture presents unique challenges, including acetabular fixation. Twelve patients with a history of acetabular fracture underwent THA with porous metal cups. The average age was 57 years (range 24-88). THA was performed at an average 20 months from initial fracture. Average follow-up was 39 months (range 24-49). Average WOMAC scores improved from 32 to 79; UCLA scores improved from 1.75 to 5.25. There was one case of acetabular loosening in a renal transplant patient with rheumatoid arthritis. No other patients showed progressive radiolucent lines. At average three-year follow-up, porous metal components afforded improved clinical and radiographic outcomes in the majority of patients. Longer follow-up will determine whether porous metal is a durable option in the management of prior acetabular fracture. PMID:23813176

Kamath, Atul F; Evangelista, Perry J; Nelson, Charles L



Analysis of stem tip pain in revision total knee arthroplasty.  


Stem tip pain following revision total knee arthroplasty is a significant cause of patient dissatisfaction, which in the presence of an aseptic well-fixed component has no widely accepted surgical solution. A definitive cause of stem tip pain remains elusive, however it has been suggested that high stress concentrations within the region of the stem tip may play a role. This paper reports a finite element study of a novel clinical technique where a plate is attached to the tibia within the region of the stem tip to reduce stem tip pain. The results demonstrate that the plate reduces stress concentrations in the bone at the stem tip of the implant. The magnitude of stress reduction is dependent upon plate location, material and attachment method. PMID:23523204

Kimpton, Christine I; Crocombe, Andrew David; Bradley, William Neil; Gavin Huw Owen, Brigstocke



Metal on metal total hip arthroplasty using modular acetabular shells.  


Metal on metal bearings were reintroduced into the United States for use in total hip arthroplasty approximately a decade ago. We evaluated a consecutive series cohort of 148 patients with 169 hips who underwent THR using a metal on metal bearing surface with a modular acetabular shell that had fixation augmentation with dome screws. At 3 to 8 year follow-up, average 4.7 years, only one component was revised (for femoral loosening). 3 hips demonstrated proximal femoral osteolysis and 3 hips demonstrated pelvic osteolysis. The average follow-up Harris Hip Score was 94 (range, 57-100). Although the results have been excellent, we continue to closely monitor these hips for any long term failures, or concerns. PMID:23489729

Liudahl, Adam A; Liu, Steve S; Goetz, Devon D; Mahoney, Craig R; Callaghan, John J



Femoral-head vascularity after hip surface arthroplasty  

PubMed Central

Background Iatrogenic devascularization of the femoral head is as an area of concern following hip resurfacing arthroplasty, with probable implications on short-term failure and long-term survival of the implant. Materials and methods We assessed the vascularity of 25 resurfaced femoral heads in 20 patients by comparison with preoperative and postoperative Tc-99m methylene diphosphonate (MDP) bone scintigraphy images, the postoperative scans being done 9 months after the surgery. Results Eight out of 25 hips (32%) showed <55% of their preoperative uptake at a mean of 9 months after surgery and were categorized as showing reduced vascularity. Conclusion Our study reveals reduction in vascularity of the femoral-head remnant as a frequent occurrence after hip resurfacing. Our study also highlights the role of bone scintigraphy as tool in assessing the vascularity of resurfaced femoral heads.

Kannan, Arun; Bal, Chandra Sekhar; Kumar, Vijay; Mittal, Ravi; Damle, Nishikant



Status of navigated total hip arthroplasty in dysplastic osteoarthritis.  


This article describes the results of 41 total hip arthroplasties (THAs) carried out using a new image-free hip navigation system. For the study, registration landmarks (tear drop, posterior rim, and inner wall of the acetabulum) were added to the hip navigation system OrthoPilot (B. Braun Aesculap, Tuttlingen, Germany). The reamer center was indicated in reference to these landmarks, and final cup angle was indicated as the radiologic angle. Forty-one total THAs to treat dysplastic osteoarthritis of the hip were performed. The difference between reamer center and cup center was 4.1 +/- 3.0 mm. The difference in cup abduction angle between navigation and radiography was 6.4 degrees +/- 5.1 degrees and of anteversion was 5.9 degrees +/- 5.0 degrees. Our preliminary clinical results showed adequate accuracy. PMID:17983111

Ohashi, Hirotsugu; Matsuura, Masanori; Okamoto, Yusaku; Ebara, Tsuneyuki; Kakeda, Kyosuke; Takahashi, Shinji



OrthoPilot total hip arthroplasty workflow and surgery.  


To analyze the workflow and navigation principles of the OrthoPilot total hip arthroplasty (THA) Version 2.0 (B. Braun-Aesculap, Tuttlingen, Germany), a consecutive series of 60 patients was used to compare the navigated intraoperative data and postoperative measurements of stem and cup position. Within the safe zone, 96.3% of 54 acetabular cups were positioned. The rotational accuracy of femoral instruments was 65 degrees in 41 THAs. The femoral offset was medialized by 6.05 mm in 76% and lateralized by 2.1 mm in 14%. The data for leg length and range of motion from 60 THAs and the navigated data were similar. Thus, the first clinical validation of the workflow of the OrthoPilot THA Version 2.0 is encouraging. PMID:16235444

Kiefer, Hartmuth; Othman, Aneis



In vivo roughening of retrieved total knee arthroplasty femoral components.  


BACKGROUND: Joint registry data highlights the higher rates of cumulative revision for younger patients undergoing TKR. One of the reasons associated with this higher revision rate may be due to the wear of the UHMWPE leading to loosening. Alternate bearing surfaces have been developed to address this problem; however, roughening of the metal bearing surface has not been demonstrated in vivo. METHOD: We recorded roughness measurements of retrieved femoral components. RESULTS: Average lateral condyle roughness was 0.032?m, compared to control values of 0.020?m, p=0.002; average medial condyle roughness was 0.028?m, compared to a control value of 0.019, p<0.001. CONCLUSION: There was a small but statistically significant roughening of femoral components in vivo compared to controls. This may have important implications for aseptic loosening of knee arthroplasty components and the decision to use scratch resistant components. PMID:23142273

Malikian, Raphael; Maruthainar, Kunalan; Stammers, John; Cannon, Steve R; Carrington, Richard; Skinner, John A; Maruthainar, Nimalan; Dowd, George; Briggs, Tim W R; Blunn, Gordon W



Perioperative Morbidity and Mortality Following Bilateral Total Hip Arthroplasty.  


There is concern about safety of bilateral total hip arthroplasty (THA).This study aims to compare in-hospital complication rates between unilateral, simultaneous and staged bilateral THAs. The Nationwide Inpatient Sample from 2002-2010 was used. Patients and complications were identified using ICD-9-CM codes. In multivariate analysis, bilateral THA had higher risk of systemic complications (Odds ratio (OR): 2.1, P<0.001) compared to unilateral procedure, whereas no significant difference existed between simultaneous and staged bilateral THAs. The rate of local complications was higher in bilateral versus unilateral (4.96% versus 4.54%, P=0.009) and in staged versus simultaneous bilateral THAs (OR: 1.75, P=0.05). Bilateral THA increases risk of systemic complications compared to unilateral surgery and simultaneous bilateral THA appears to be safer than staging during one hospitalization. PMID:23664280

Rasouli, Mohammad R; Maltenfort, Mitchell G; Ross, David; Hozack, William J; Memtsoudis, Stavros G; Parvizi, Javad



[Total knee arthroplasty today: what should we tell our patients?].  


Total knee arthroplasty (TKA) remains the preferred treatment for patients with invalidating osteoarthritis. It allows these patients to find once again a satisfactory quality of life. These results are reflected by the increasing number of interventions performed each year and in always younger patients. The objective of this review of the scientific literature was to determine the long-term quantitatively and qualitatively results of TKA and determine the parameters which could influence the long-term outcome. There does not seem to be any clear arguments in favor of one type of implant or surgical technique. One also notices that TKA in females and older patients seem to have longer lifespan, estimated to approximately 15 years. The most frequent complication remains aseptic loosening followed by infections. PMID:19160639

Boulos, Karen; Jolles-Haeberli, Brigitte M



The effect of malnutrition on patients undergoing elective joint arthroplasty.  


Malnutrition has been linked to serious complications in patients undergoing elective total joint arthroplasty (TJA). This study prospectively evaluated 2,161 patients undergoing elective TJA for malnutrition as defined by either an abnormal serum albumin or transferrin. The overall incidence of malnutrition was 8.5% (184 of 2,161) and the rate of overall complications in the malnourished group was 12% as compared to 2.9% in patients with normal parameters (P<0.0001). Malnutrition predicted serious complications involving hematoma formation, infection, renal and cardiac complications. Obesity, defined by a body mass index (BMI) of 30kg/m(2) was present in 42.9% of malnourished patients with a significantly higher complication rate in this cohort. Malnutrition remains prevalent in patients >55years-old undergoing TJA and is associated with a significant increase in post-operative complications. PMID:23993346

Huang, Ronald; Greenky, Max; Kerr, Glenn J; Austin, Matthew S; Parvizi, Javad



Minimally Invasive Total Knee Arthroplasty: Is it for Everybody?  

PubMed Central

The development of new instrumentation and techniques has led to the rapid advancement of less invasive surgical approaches in total knee arthroplasty (TKA). Compared to the standard approach, minimally invasive surgery (MIS) in TKA was shown to reduce postoperative pain, blood loss, and hospitalization time, and to improve functional recovery. Growing experience with MIS-TKA has defined the proper indications for this technique. With a limited exposure, the skin, capsular tissues, and bone surfaces receive higher stresses because of the retraction required. Several complications relating to the MIS learning curve are now being reported. The reliability of a TKA procedure performed through a mini-incision, and its success, seems to depend on patient selection, surgeon experience, and surgical environment.

Baldini, Andrea; Giron, Francesco; Sensi, Lorenzo



Metallic wear debris in dual modular hip arthroplasty.  


Two cementless hip arthroplasty models with a modular neck made titanium alloy were submitted to cyclical loading in air, in physiological solution, and in a solution for accelerated corrosion tests in order to study the damage process of modular couplings. Thereafter, on one of the two models a series of tests were conducted in order to evaluate the quality of debris produced by the couplings. The parameters of testing adopted allow us to estimate the production of metallic debris observable in vivo with this type of prosthetic stem. The results show that the couplings of modular prostheses may be the source of metallic debris. The amount of debris produced depends on the geometry of the coupling and of the entire implant. Good planning and realization of the couplings, however, reduce the phenomenon that is negligible as compared to other potential sources of debris such as the surface of the stem or of the prosthetic head. PMID:9494240

Baleani, M; Viceconti, M; Walchholz, K; Toni, A


Bilateral hip arthroplasty: is 1-week staging the optimum strategy?  

PubMed Central

Seventy-nine patients underwent bilateral hip arthroplasty staged either at 1 week (Group 1) or after greater intervals (as suggested by the patients, mean 44 weeks, range 16-88 weeks) (Group 2), over a five year period at one Institution. Sixty-eight patients (29 bilateral hip resurfacings and 39 total hip replacements) completed questionnaires regarding their post-operative recovery, complications and overall satisfaction with the staging of their surgery. There was no significant age or ASA grade difference between the patient groups. Complication rates in the two groups were similar and overall satisfaction rates were 84% in Group 1 (n = 32) and 89% in Group 2 (n = 36). Cumulative hospital lengths of stay were significantly longer in Group 1 patients (11.9 days vs 9.1 days)(p < 0.01); this was true for both hip resurfacing and total hip arthroplasty patients, however resurfacing patients stays were significantly shorter in both groups (p < 0.01). Postoperative pain resolved earlier in Group 1 patients at a mean of 20.9 weeks compared with a cumulative 28.9 weeks (15.8 and 13.1 weeks) for Group 2 patients (p = 0.03). The mean time to return to part-time work was 16.4 weeks for Group 1, and a cumulative 17.2 weeks (8.8 and 8.4 weeks) for Group 2. The time to return to full-time work was significantly shorter for Group 1 patients (21.0 weeks, compared with a cumulative 29.7 weeks for Group 2)(p < 0.05). The time to return to both full and part-time work was significantly shorter in total hip replacement patients with 1-week staging compared with delayed staging (22.0 vs 35.8 weeks (p = 0.02), and 13.8 vs 19.3 weeks (p = 0.03) respectively). Hip resurfacing patients in Group 2 had significantly shorter durations of postoperative pain and were able to return to part-time and full time work sooner than total hip arthroplasty patients. There was a general trend towards a faster recovery and resumption of normal activities following the second operation in Group 2 patients, compared with the first operation. Bilateral hip arthroplasty staged at a 1-week interval resulted in an earlier resolution of hip pain, and an earlier return to full-time work (particularly following total hip replacement surgery), with high levels of patient satisfaction and no increased risk in complications; however the hospital length of stay was significantly longer. The decision for the timing of staged bilateral surgery should be made in conjunction with the patient, making adjustments to accommodate their occupational needs and functional demands.



Treatment strategies for infection after reverse shoulder arthroplasty.  


INTRODUCTION: Infection after reverse shoulder arthroplasty (RSA) is a disastrous complication. No clear guidelines describing specific management strategies for infection after RSA are available. METHODS: We retrospectively analyzed 20 patients treated for deep infection after RSA. Initial irrigation and debridement and exchange of the polyethylene inlay were performed in seven patients, and initial two-stage revision was performed in 12 and initial resection arthroplasty in one patient. Patient charts were reviewed for risk factors, clinical symptoms and investigations of those symptoms, pre- and postoperative X-rays, interval until revision surgery, causative bacteria, complications, final clinical outcome and patient satisfaction. RESULTS: The mean overall postoperative Constant-Murley Score (CMS) was 42.6 points, the mean UCLA score was 20.8, the mean simple shoulder test (SST) was 5.5, and the mean VAS was 1.5. When comparing the CMS, UCLA score and the SST between the revision RSA group and the resection group, significant differences between the groups were found (p < 0.05). Irrigation, debridement and exchange of the polyethylene inlay were successful only in two of the four patients with acute infection. The three patients with subacute infections were treated with initial irrigation and debridement and exchange of the polyethylene inlay, which were not successful. CONCLUSION: The relatively high patient satisfaction can be explained by the low pain level once the patient is free from infection. However, functional results are poor in most cases, and this possible outcome must be discussed with the patient in the preoperative setting. PMID:23748670

Ortmaier, Reinhold; Resch, Herbert; Hitzl, Wolfgang; Mayer, Michael; Stundner, Ottokar; Tauber, Mark



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.

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



Component rotational alignment in unexplained painful primary total knee arthroplasty.  


BACKGROUND: Rotational malalignment of the components in total knee arthroplasty (TKA) can be a factor in poor outcomes but has yet to be defined. This study compares the rotational alignment of components in a cohort of 56 patients with unexplained pain following total knee arthroplasty with a matched control cohort of 56 patients with cemented Nex Gen Legacy posterior stabilised (LPS) flex fixed bearing TKA between March 2006 and May 2010. The aim of the study was to define an acceptable limit of rotation in total knee replacement. METHODS: Rotational alignment was calculated using the Berger protocol with post operative computerised tomography scanning. The alignment parameters measured were tibial and femoral component rotations and the combined component rotations and the component rotational mismatch. RESULTS: The two cohorts were demographically matched. Excessive internal rotation of the components was defined using the tenth percentile of rotations in the control cohort. Values of excessive internal rotation were 5.8° of the tibial component, 3.9° of the femoral component, 8.7° of combined rotation and 5.6° of the component mismatch. No significant difference was identified in excessive external rotation in any of the parameters. A significant difference in the mean rotations between the two cohorts was identified with internal rotation of the components in the painful cohort and external rotation on the control cohort. CONCLUSIONS: We identified internal rotation malalignment of the tibial (p=0.0003) and femoral (p=0.014) components individually as well as the combined component rotation (p=0.0003) and component rotation mismatch (p=0.0001) to be a factor in pain following TKA. External rotation of any of the component parameters was not identified to be a factor in painful TKA. This study adds to the understanding of rotational alignment in TKA and suggests limits of internal rotation alignment associated with painful Nex Gen Legacy posterior stabilised (LPS) flex fixed bearing TKA. LEVEL OF EVIDENCE: Level III. PMID:23140906

Bell, Stuart W; Young, Peter; Drury, Colin; Smith, Jules; Anthony, Iain; Jones, Bryn; Blyth, Mark; McLean, Angus



Ambulatory Continuous Posterior Lumbar Plexus Nerve Blocks after Hip Arthroplasty  

PubMed Central

Background The authors tested the hypotheses that after hip arthroplasty, ambulation distance is increased and the time required to reach three specific readiness-for-discharge criteria is shorter with a 4-day ambulatory continuous lumbar plexus block (cLPB) than with an overnight cLPB. Methods A cLPB consisting of 0.2% ropivacaine was provided from surgery until the following morning. Patients were then randomly assigned either to continue ropivacaine or to be switched to normal saline. Primary endpoints included (1) time to attain three discharge criteria (adequate analgesia, independence from intravenous analgesics, and ambulation ? 30 m) and (2) ambulatory distance in 6 min the afternoon after surgery. Patients were discharged with their cLPB and a portable infusion pump, and catheters were removed on the fourth postoperative day. Results Patients given 4 days of perineural ropivacaine (n = 24) attained all three discharge criteria in a median (25th-75th percentiles) of 29 (24-45) h, compared with 51 (42-73) h for those of the control group (n = 23; estimated ratio = 0.62; 95% confidence interval, 0.45-0.92;P = 0.011). Patients assigned to receive ropivacaine ambulated a median of 34 (9-55) m the afternoon after surgery, compared with 20 (6-46) m for those receiving normal saline (estimated ratio = 1.3; 95% confidence interval, 0.6-3.0;P = 0.42). Three falls occurred in subjects receiving ropivacaine (13%),versusnone in subjects receiving normal saline. Conclusions Compared with an overnight cLPB, a 4-day ambulatory cLPB decreases the time to reach three predefined discharge criteria by an estimated 38% after hip arthroplasty. However, the extended infusion did not increase ambulation distance to a statistically significant degree.

Ball, Scott T.; Gearen, Peter F.; Le, Linda T.; Mariano, Edward R.; Vandenborne, Krista; Duncan, Pamela W.; Sessler, Daniel I.; Enneking, F. Kayser; Shuster, Jonathan J.; Theriaque, Douglas W.; Meyer, R. Scott



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.



Investigations into alternate spark gap switching techniques  

Microsoft Academic Search

This report documents the design, operation, and experimental results of the evaluation of a new spark gap triggering method. These spark gaps were developed to support ARL's ongoing nuclear electromagnetic pulse (EMP) current injection assessment programs. This trigger method provides operator control, multiple spark gap control with synchronous triggering, and a limited amount of hardware to control the spark gap

Brian G. Smith




SciTech Connect

During the RHIC Au-run in 2001 the 200 MHz storage cavity system was used for the first time. The rebucketing procedure caused significant beam debunching in addition to amplifying debunching due to other mechanisms. At the end of a four hour store, debunched beam could account for approximately 30%-40% of the total beam intensity. Some of it will be in the abort gap. In order to minimize the risk of magnet quenching due to uncontrolled beam losses at the time of a beam dump, a combination of a fast transverse kicker and copper collimators were used to clean the abort gap. This report gives an overview of the gap cleaning procedure and the achieved performance.




Stacked insulator induction accelerator gaps  

SciTech Connect

Stacked insulators, with alternating layers of insulating material and conducting film, have been shown to support high surface electrical field stresses. We have investigated the application of the stacked insulator technology to the design of induction accelerator modules for the Relativistic-Klystron Two-Beam Accelerator program. The rf properties of the accelerating gaps using stacked insulators, particularly the impedance at frequencies above the beam pipe cutoff frequency, are investigated. Low impedance is critical for Relativistic-Klystron Two-Beam Accelerator applications where a high current, bunched beam is trsnsported through many accelerating gaps. An induction accelerator module designs using a stacked insulator is presented.

Houck, T.I.; Westenskow, G.A.; Kim, J.S.; Eylon, S.; Henestroza, E.; Yu, S.S.; Vanecek, D.



Failure of Larger-Diameter Metal-on-Metal Total Hip Arthroplasty Resulting from Anterior Iliopsoas Impingement  

Microsoft Academic Search

Anterior iliopsoas impingement is a recognized cause of persistent groin pain after total hip arthroplasty. We report 3 patients with failed total hip arthroplasties resulting from anterior iliopsoas and capsular impingement secondary to a metal femoral ball with a diameter larger than the native femoral head. All patients had the same implant design. Resolution of symptoms occurred in all patients

James A. Browne; David J. Polga; Rafael J. Sierra; Robert T. Trousdale; Miguel E. Cabanela



Artroplastia total do quadril não cimentada em pacientes com artrite reumatóide * Uncemented total hip arthroplasty in patients with rheumatoid arthritis  

Microsoft Academic Search

Objective: To analyze clinical, functional, and radiographic results of uncemented total hip arthroplasties in patients with rheumatoid arthritis. Methods: Retrospective study of 24 patients (28 hips) with rheumatoid arthritis submitted to total hip arthroplasty, using uncemented femoral prosthesis Secur Fit Osteonics ® , with minimum follow-up of two years. The patients were clinically evaluated using the Merle D'Aubigné criteria and




The (Non-)Existence of Gapping in Chinese and Its Implications for the Theory of Gapping.  

ERIC Educational Resources Information Center

Shows that there are at least two types of gapping in natural languages: canonical gapping and LPD. Argues that Chinese has some gapping sentences that result from ATB movement from V to "v." Data from Chinese affirm Johnson's (1994) theory of gapping that gapping occurs in those languages only with verb movement. (Author/VWL)

Tang, Sze-Wing



Multiple input electrode gap controller  


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.




EPA Science Inventory

Gap Junctions (GJs) provide cell-to-cell communication (GJIC) of essential metabolites and ions. Js allow tissues to average responses, clear waste products, and minimize the effects of xenobiotics by dilution and allowing steady-state catabolism. any chemicals can adversely affe...


SmartGAP User's Guide.  

National Technical Information Service (NTIS)

This document is the users guide for the Smart Growth Area Planning (SmartGAP) software, which is a tool for evaluating the impact of various smart growth policies. The tool was developed as part of the SHRP 2 C16 project, which provided tools, methods, a...

K. Kockelman R. Cerver



Bridging the Music Semantic Gap  

Microsoft Academic Search

In this paper we present the music information plane and the dieren t levels of information extraction that exist in the musical domain. Based on this approach we propose a way to overcome the existing se- mantic gap in the music eld. Our approximation is twofold: we propose a set of music descriptors that can automatically be extracted from the

Oscar Celma; Perfecto Herrera; Xavier Serra


A simple triggered vacuum gap  

Microsoft Academic Search

A simple triggered vacuum gap has previously been described by the authors in this journal (see ibid., vol.5, 415, 1972). Further studies have resulted in improvement of the performance with regard to sensitivity and consistency of the trigger characteristics and immunity from bridging due to metal particles eroded from the arc. The earlier design suffered from rather frequent bridging of

N. Vidyardhi; R. S. N. Rau



Multiple input electrode gap controller  


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)



Brain Responses to Filled Gaps  

ERIC Educational Resources Information Center

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…

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



Comprehensive Look at Blood Transfusion Utilization in Total Joint Arthroplasty at a Single Academic Medical Center under a Single Surgeon  

PubMed Central

The utilization of autologous and allogeneic transfusions in total joint arthroplasties was to characterize patients who may benefit from giving preoperative blood donations. We conducted a retrospective chart review of 525 patients to document preoperative hematocrit, estimated blood loss, length of stay, transfusions, and medical comorbidities. Results of our review showed that total hip arthroplasty revision (THA-R) had the highest prevalence of transfusions (60%) followed by total hip arthroplasty (THA, 53%), total knee arthroplasty-revision (TKA-R, 33%), and total knee arthroplasty (TKA, 23%). There was significant waste of autologous donations: 92% of TKA patients, 64% of THA, and 33% of THA-R patients wasted on average 1.527, 1.321, and 1.5 autologous units, respectively. Pre-operative hematocrit was the strongest predictor of future transfusion need across all procedures, and primary THA had additional predictors in age and gender.

Volin, Sam; Sun, Yung-Chi; Moore, Matthew; Cassidy, Charles



Zirconia versus Co-Cr femoral heads in total hip arthroplasty: early assessment of wear.  


Polyethylene wear and associated osteolysis are major limitations to the long-term success of total hip arthroplasty. In vitro laboratory studies suggest polyethylene wear in THA may be substantially reduced with ceramic femoral heads. We evaluated the potential value of zirconia ceramic on conventional polyethylene as an "alternative bearing" for total hip arthroplasty in a prospective, randomized clinical trial in comparison with femoral heads made of Co-Cr-Mo. Patients were evaluated with standardized clinical outcome instruments, and measurement of head penetration was performed with computerized wear measurement software. Study enrollment was halted because of a recall of the zirconia heads. At that time, 30 total hip arthroplasties with Co-Cr-Mo heads and 30 total hip arthroplasties with zirconia heads had been performed. Mean followup was similar for both groups (Co-Cr- Mo = 51.7 months; zirconia = 51.2 months). The mean annual head penetration rate was low and similar for both groups (Co-Cr-Mo = 0.060 mm/year; and zirconia = 0.055 mm/year). In view of the recently reported potential for zirconia ceramics to undergo monoclinic phase transformation in vivo, with resultant increased fracture risk and degradation of wear properties, we do not recommend use of zirconia femoral heads as an "alternative bearing" for total hip arthroplasty. PMID:17312588

Kraay, Matthew J; Thomas, Rebecca D; Rimnac, Clare M; Fitzgerald, Steven J; Goldberg, Victor M



Arthroscopic irrigation and debridement of infected total knee arthroplasty: report of two cases.  


Various methods have been described for the treatment of the acutely infected total knee arthroplasty. These include antibiotic suppression, open debridement and irrigation, exchange arthroplasty, resection arthroplasty, arthrodesis, and amputation. A method not frequently reported is arthroscopic irrigation and debridement. Two cases of acutely infected total knee arthroplasty treated with arthroscopic irrigation and debridement are presented. In both cases there was a benign postoperative course averaging five months. Both infections were secondary to hematogenous seeding from a distant focus of infection. The patients presented within approximately 12 h after the onset of knee symptoms and were taken for arthroscopic irrigation and debridement within 12 h after presentation. Gram-positive organisms sensitive to the antibiotics being used were cultured in both. Postoperative knee function and range of motion returned rapidly and disability was minimal. At average 30-month follow-up both patients were pain free, had full activity of daily living, and had no clinical or radiographic evidence of infection. Arthroscopic irrigation and debridement appears to be an effective method of treatment in select cases of infected total knee arthroplasty. PMID:3166657

Flood, J N; Kolarik, D B



SLIC: Secure Loadable Interposition Code  

Microsoft Academic Search

This paper presents a method for extending operating system functionality in a way that is secure, efficient, simple, requires no kernel source changes, and is compatible with existing application binaries. Our approach is to enable extensions of the system call interface by loading a device driver into the kernel that redirects system calls to extension code running either in the

Douglas P. Ghormley; David Petrou; Thomas E. Anderson



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



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



Emplacement Gantry Gap Analysis Study  

SciTech Connect

To date, the project has established important to safety (ITS) performance requirements for structures, systems, and components (SSCs) based on the identification and categorization of event sequences that may result in a radiological release. These performance requirements are defined within the ''Nuclear Safety Design Bases for License Application'' (NSDB) (BSC 2005 [DIRS 171512], Table A-11). Further, SSCs credited with performing safety functions are classified as ITS. In turn, assurance that these SSCs will perform as required is sought through the use of consensus codes and standards. This gap analysis is based on the design completed for license application only. Accordingly, identification of ITS SSCs beyond those defined within the NSDB are based on designs that may be subject to further development during detail design. Furthermore, several design alternatives may still be under consideration to satisfy certain safety functions, and final selection will not be determined until further design development has occurred. Therefore, for completeness, alternative designs currently under consideration will be discussed throughout this study. This gap analysis will evaluate each code and standard identified within the ''Emplacement Gantry ITS Standards Identification Study'' (BSC 2005 [DIRS 173586]) to ensure each ITS performance requirement is fully satisfied. When a performance requirement is not fully satisfied, a gap is highlighted. This study will identify requirements to supplement or augment the code or standard to meet performance requirements. Further, this gap analysis will identify nonstandard areas of the design that will be subject to a design development plan. Nonstandard components and nonstandard design configurations are defined as areas of the design that do not follow standard industry practices or codes and standards. Whereby, assurance that an SSC will perform as required may not be readily sought though the use of consensus standards. This gap analysis is prepared by the Emplacement and Retrieval (E&R) project team and is intended for the sole use of the Engineering department in work regarding the emplacement gantry. Yucca Mountain Project personnel from the E&R project team should be consulted before use of this gap analysis for purposes other than those stated herein or by individuals other than authorized by the Engineering department.

R. Thornley



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.

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



Femoral rotation in ligament balanced knee arthroplasty: a prospective clinical study.  


Rotational alignment of the femoral component is an important factor to achieve beneficial results in total knee arthroplasty. Femoral rotation pre versus post surgery was prospectively assessed in 40 patients who underwent ligament balanced knee arthroplasty. Computerized tomography of the knee was performed before and after the surgery to determine the femoral rotation. In 36 out of 40 patients the rotation of the femoral implants differed compared to the preoperative femur (P > 0.001). After surgery the rotational alignment of the femoral component ranged from -3° (internal rotation) to 7° (external rotation). Increased external rotation was found in 33 out of 40 patients ranging from 1° to 7°. These results highlight the importance of individually determined femoral rotation in ligament balanced knee arthroplasty. PMID:23540534

Kaipel, Martin; Gergely, Istvan; Sinz, Katrina; Neumann, Christian; Sinz, Günter



Simultaneous Bilateral Computer Assisted Total Knee Arthroplasty: The Effect of Intravenous or Intraarticular Tranexamic Acid.  


The use of tranexamic acid (TA) in total knee arthroplasty is well documented. However, there is limited evidence to suggest the use of TA in simultaneous bilateral computer assisted total knee arthroplasty (CATKA). We, therefore, studied the effect of TA, in simultaneous bilateral computer assisted total knee arthroplasty, in terms of blood transfusion, routes of administration and complications. We divided 90 patients into three groups. Group I patients received intravenous normal saline alone (IVNS group). Group II received intravenous TA alone (IVTA group). Group III received intraarticular TA alone (IATA group). Our study confirms that there is significant benefit of using TA but no difference between the intravenous or intraarticular routes of administration. PMID:23642448

Hegde, Chintan; Wasnik, Sandeep; Kulkarni, Sourabh; Pradhan, Sameer; Shetty, Vijay



Arthrodesis of the hip and conversion to total hip arthroplasty: a systematic review.  


A systematic review of the literature was performed in order to evaluate the outcomes following arthrodesis of the hip and subsequent conversion to total hip arthroplasty. Eight studies regarding primary hip arthrodesis evaluating 249 hips revealed variable union rates (37.5%-100%) and patient satisfaction rates (69%-100%). Adjacent joint pain was commonly seen in the lower back (up to 75%) and ipsilateral knee (up to 57%) and complications were reported in 8.4%. Eleven studies regarding conversion arthroplasty evaluating 579 patients revealed inconsistent results regarding relief of pain. Complications were seen in up to 54%, most commonly due to mechanical failure, deep infection and nerve palsy. Whilst hip arthrodesis can provide pain relief and patient satisfaction, conversion arthroplasty is associated with an unacceptably high complication rate. PMID:23523503

Jain, Sameer; Giannoudis, Peter V



Revision total knee arthroplasty: infection should be ruled out in all cases.  


We hypothesized that some aseptic revision total knee arthroplasty failures are indeed caused by occult infection. This prospective study recruited 65 patients undergoing revision total knee arthroplasty. The mean follow-up period was 19 months. Collected synovial fluid was analyzed by Ibis T5000 biosensor (Abbott Molecular Inc, Ill; a multiplex polymerase chain reaction technology). Cases were considered as infected or aseptic based on the surgeon's judgment and Ibis findings. Based on Ibis biosensor, 17 aseptic cases were indeed infected that had been missed. Of these 17 cases, 2 developed infection after the index revision. A considerable number of so-called aseptic failures seem to be occult infections that were not adequately investigated and/or miscategorized as aseptic failure. We recommend that all patients undergoing revision arthroplasty be investigated for periprosthetic joint infection. PMID:22386605

Rasouli, Mohammad R; Harandi, Armin Aalami; Adeli, Bahar; Purtill, James J; Parvizi, Javad



Postoperative morbidity and mortality following total knee arthroplasty with computer navigation.  


The incidence of postoperative complications following computer navigated total knee arthroplasty is unknown. There is no published evidence to support decreased morbidity compared to standard conventional technique. The Nationwide Inpatient Sample database was used to identify 101,596 patients who underwent total knee arthroplasty in 2005. Of these patients, 1156 were coded as having a computer-assisted procedure. Bivariate analysis and regression modeling were used to compare postoperative in-hospital outcomes between the computer-assisted and non-navigated cohorts. We found no differences in postoperative mortality or complications for the majority of our measured outcomes. Under multivariate regression analysis, computer navigation was associated with a lower rate of postoperative cardiac complications (odds ratio 0.40, p=0.042), a shorter length of stay, and a trend towards fewer hematomas. Further clinical study is required to examine the possible association of computer navigation with postoperative morbidity following knee arthroplasty. PMID:19758806

Browne, James A; Cook, Chad; Hofmann, Aaron A; Bolognesi, Michael P



Immediate cementless total hip arthroplasty for the treatment of active tuberculosis.  


We report the results of a primary total hip arthroplasty (THA) in 7 patients with advanced active tuberculous arthritis of the hip and had lost the chance of preserving the hip without replacement surgery. Tuberculosis was confirmed in all cases by the culture or histological examination. All patients were treated with primary THA followed by antituberculous medications for 1 year. Cementless stems and sockets were used in all patients. The average follow-up period was 4.8 years. The reactivation of the infection was not detected in all cases. The result was excellent in all patients according to the Harris Hip Score. Total hip arthroplasty in the tuberculous hip is a safe procedure and produces superior functional results compared with resection arthroplasty or arthrodesis. The results of primary THA in the selected patients was satisfactory as they rapidly recover from the disease. PMID:16230246

Yoon, Taek Rim; Rowe, Sung Man; Santosa, Setyagung Budi; Jung, Sung Taek; Seon, Jong Keun



Etidronate does not suppress periprosthetic bone loss following cemented hip arthroplasty.  


Periprosthetic bone loss after arthroplasty may threaten prosthesis survival. The current study investigated the effect of etidronate therapy on periprosthetic, contralateral hip, and spine bone mineral density (BMD) in a one-year, prospective, randomized, double-blind study on 46 patients after cemented hip arthroplasty. BMD was measured with dual-energy X-ray absorptiometry (DXA). There were no significant differences between mean BMD measurements of the etidronate and placebo groups, with the exception of the mean percent change in the spine at six months and 12 months and in Gruen zone 3 at six months; in all three cases, the etidronate group had significantly greater mean values. These findings suggest that cyclic etidronate therapy has no significant effect in suppressing periprosthetic bone loss following cemented hip arthroplasty. PMID:16193347

Fokter, S K; Komadina, R; Repse-Fokter, A; Yerby, S A; Kocijancic, A; Marc, J



Etidronate does not suppress periprosthetic bone loss following cemented hip arthroplasty  

PubMed Central

Periprosthetic bone loss after arthroplasty may threaten prosthesis survival. The current study investigated the effect of etidronate therapy on periprosthetic, contralateral hip, and spine bone mineral density (BMD) in a one-year, prospective, randomized, double-blind study on 46 patients after cemented hip arthroplasty. BMD was measured with dual-energy X-ray absorptiometry (DXA). There were no significant differences between mean BMD measurements of the etidronate and placebo groups, with the exception of the mean percent change in the spine at six months and 12 months and in Gruen zone 3 at six months; in all three cases, the etidronate group had significantly greater mean values. These findings suggest that cyclic etidronate therapy has no significant effect in suppressing periprosthetic bone loss following cemented hip arthroplasty.

Komadina, R.; Repse-Fokter, A.; Yerby, S. A.; Kocijancic, A.; Marc, J.



Increased revision rates after total knee arthroplasty in patients who smoke.  


The purpose of this study was to compare the clinical outcomes of total knee arthroplasty in patients who reported a history of tobacco use with those who were nonsmokers. Between 2006 and 2009, there were 131 total knee arthroplasties performed in patients who were smokers and 490 in patients who did not smoke. At a mean follow-up of 47 months (range, 24-79 months), the patients who were smokers had a statistically decreased overall survivorship of 90% (13 revisions) compared with 99% (5 revisions) in the nonsmokers. Surgical complication rates were not significantly different between the 2 groups; however, there was a significant difference in medical complications. Total knee arthroplasty in smokers has a higher risk of negative clinical outcomes compared with nonsmokers. PMID:22633104

Kapadia, Bhaveen H; Johnson, Aaron J; Naziri, Qais; Mont, Michael A; Delanois, Ronald E; Bonutti, Peter M



Results after Late Polymicrobial, Gram-negative, and Methicillin-resistant Infections in Knee Arthroplasty  

Microsoft Academic Search

Background  Previous studies of knee arthroplasty infections caused by high-virulence organisms suggest poor outcomes. Polymicrobial and\\u000a Gram-negative infections are less studied.\\u000a \\u000a \\u000a \\u000a \\u000a Questions\\/purposes  This study compared the results of treatment of knee arthroplasty infections by single versus polymicrobial isolates, Gram-positive\\u000a versus Gram-negative, and methicillin-resistant versus -sensitive Staphylococci.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  We prospectively followed 47 patients with late knee arthroplasty infections. The mean age was 72 years (range,

José Cordero-Ampuero; Jaime Esteban; Eduardo García-Rey



Increasing risk of prosthetic joint infection after total hip arthroplasty  

PubMed Central

Background and purpose The risk of revision due to infection after primary total hip arthroplasty (THA) has been reported to be increasing in Norway. We investigated whether this increase is a common feature in the Nordic countries (Denmark, Finland, Norway, and Sweden). Materials and methods The study was based on the Nordic Arthroplasty Register Association (NARA) dataset. 432,168 primary THAs from 1995 to 2009 were included (Denmark: 83,853, Finland 78,106, Norway 88,455, and Sweden 181,754). Adjusted survival analyses were performed using Cox regression models with revision due to infection as the endpoint. The effect of risk factors such as the year of surgery, age, sex, diagnosis, type of prosthesis, and fixation were assessed. Results 2,778 (0.6%) of the primary THAs were revised due to infection. Compared to the period 1995–1999, the relative risk (with 95% CI) of revision due to infection was 1.1 (1.0–1.2) in 2000–2004 and 1.6 (1.4–1.7) in 2005–2009. Adjusted cumulative 5–year revision rates due to infection were 0.46% (0.42–0.50) in 1995–1999, 0.54% (0.50–0.58) in 2000–2004, and 0.71% (0.66–0.76) in 2005–2009. The entire increase in risk of revision due to infection was within 1 year of primary surgery, and most notably in the first 3 months. The risk of revision due to infection increased in all 4 countries. Risk factors for revision due to infection were male sex, hybrid fixation, cement without antibiotics, and THA performed due to inflammatory disease, hip fracture, or femoral head necrosis. None of these risk factors increased in incidence during the study period. Interpretation We found increased relative risk of revision and increased cumulative 5–year revision rates due to infection after primary THA during the period 1995–2009. No change in risk factors in the NARA dataset could explain this increase. We believe that there has been an actual increase in the incidence of prosthetic joint infections after THA.



[Design of an unconventional interlocked hip arthroplasty system (RIMAG) from Mexican femoral measurement].  


The need in resolving massive bone losses in hip region caused by tumors, infections, trauma or failed arthroplasties in 17 years of the Bone Tumors Department of the National Rehabilitation Institute, Mexico City, and data obtained from different studies: 1) Biomechanic study of an unconventional hip arthroplasty system, 2) Tridimensional model of a human femur by the finite element method, 3) Biomechanical analysis of a system bone-implant for reconstruction of the proximal third of the femur by the finite element method, 4) Incidence of tumor and pseudotumor bone and soft tissue lesions of the hip, generated the project of designing an unconventional interlocked hip arthroplasty system for femur reconstruction. Two processes were done for adequate manufacturing and dimensioning: Anthropomorphometric study of Mexican femora; 2) Design of an unconventional hip arthroplasty system with the following characteristics: first, the arthroplasty system is constituted by an intramedullar stem, is fixated to femur with interlocking screws, this fixation method was inspired from the design of intramedullar nails of Dr. Fernando Colchero Rosas. The system has a second fixation system in the femur cut region, resolved by a fenestrated support introduced in the cortical wall. Once data was processed, the need for manufacturing 2 models was determined: 1) One for the proximal 11 cm of the femur and 2) other for the 12 distal cm. The height of interlocking screws, 2 models of intracortical proximal support (one fixated and one fixable with an expansible screw), were designed. Diameter, length of the stems, size of spacers and supports were determined for adequate interlocking fixation. We designed the instruments for assembling, impaction and orientation of the arthroplasty system. The system was presented to the Mexican Institute of Industrial Property, at March 15, 1996 and the patent was conceded April 19, 2007 (#245717). PMID:18669306

Martínez, Genaro Rico; Domínguez, Víctor H; Muller, José Antonio; Cedillo, Ernesto A Delgado; Roa, Josué Antonio Miranda; Montoya, Roberto C


Total hip arthroplasty in young adults, with focus on Perthes' disease and slipped capital femoral epiphysis  

PubMed Central

Background and purpose Pediatric hip diseases account for 9% of all primary hip arthroplasties in the Norwegian Arthroplasty Register. We wanted to validate the diagnosis as reported to the register and to assess the quality of life of these patients after hip replacement. Patients and methods 540 patients accepted to participate in this follow-up study (634 hips). All were less than 40 years of age and had been reported to the Norwegian Arthroplasty Register as having undergone a primary total hip arthroplasty (THA) between 1987 and 2007. The underlying diagnosis, age at diagnosis, and type of treatment given prior to the hip replacement were recorded from the original hospital notes. Results The diagnoses reported to the Norwegian Arthroplasty Register were confirmed to be correct in 91% of all cases (538/592). For the 94 hips that had been treated due to Perthes' disease or slipped capital femoral epiphysis (SCFE), the diagnosis was verified in 95% of cases (89/94). The corresponding proportion for inflammatory hip disease was 98% (137/140) and it was only 61% for primary osteoarthritis (19/31). The self reported quality of life (EQ-5D) was poorer for these young patients with THA than for persons in age-matched cohorts from Great Britain and Sweden, except for those with an underlying SCFE. Interpretation The diagnoses reported to the Norwegian Arthroplasty Register as the underlying cause of THA were correct in 91% of cases. Individuals who undergo THA before the age of 40 have a reduced quality of life, except for those requiring a hip replacement because of SCFE.



Supports used for positioning of patients in hip arthroplasty: is there an infection risk?  

PubMed Central

INTRODUCTION Infection after joint arthroplasty is a disastrous complication. Implants used in hip arthroplasty increase the risk of infection from organisms of low pathogenicity. Potential reservoirs, that have not been assessed as yet, are the supports used for patient positioning in hip arthroplasty. The purpose of this study was to assess these supports for presence of bacterial pathogens. SUBJECTS AND METHODS We studied 40 supports used in 20 hip arthroplasty procedures. Tryptone soya agar plates were used to sample these supports. All agar plates were incubated at 37°C for 48 h. RESULTS Of the 20 anterior supports, 17 (85%) showed bacterial colonisation; of the 20 posterior supports, 10 (50%) had bacterial colonisation. Fourteen (52%) supports were contaminated with one organism, 9 (33%) with two organisms, three (11%) with three organisms and one (4%) with four organisms. Coagulase-negative staphylococci were the most common isolated organisms (61%) followed by coryneforms (10%) and bacilli (10%). Anterior supports had two times more colony forming units compared to the posterior supports. CONCLUSIONS This study showed contamination of supports used for positioning patients during hip arthroplasty. It reflects poor cleaning practice and certainly raises the possibility that a high bacterial load on these supports may contribute to higher infection rates in hip arthroplasties. The study raises concerns related to contamination of supports, as there is a potential for cross-infection, wound problems, and deep sepsis around implants which could be disastrous. While colonisation does not equate with infection, we suggest thorough cleaning of the supports before and after every surgical procedure.

Ahmad, Riaz; Tham, Ji; Naqvi, Syed Ghufran Ali; Butt, Umer; Dixon, John



Finding All Approximate Gapped Palindromes  

Microsoft Academic Search

We study the problem of finding all maximal approximate gapped palindromes in a string. More specifically, given a string S of length n, a parameter q???0 and a threshold k?>?0, the problem is to identify all substrings in S of the form uvw such that (1) the Levenshtein distance between u and w\\u000a \\u000a r\\u000a is at most k, where w

Ping-hui Hsu; Kuan-yu Chen; Kun-mao Chao



Energy Gaps in Graphene Nanoribbons  

Microsoft Academic Search

Based on a first-principles approach, we present scaling rules for the band\\u000agaps of graphene nanoribbons (GNRs) as a function of their widths. The GNRs\\u000aconsidered have either armchair or zigzag shaped edges on both sides with\\u000ahydrogen passivation. Both varieties of ribbons are shown to have band gaps.\\u000aThis differs from the results of simple tight-binding calculations or solutions

Young-Woo Son; Marvin L. Cohen; Steven G. Louie



New functions for gap junctions  

Microsoft Academic Search

The most significant finding of the past year in gap junction research has been the association of connexin defects with human diseases. Connexin32 mutations cause X-linked Charcot-Marie-Tooth disease, a demyelinating peripheral neuropathy. Mutations in connexin43 may underlie cardiac malformations in visceroatrial heterotaxia syndromes. Genetic approaches and gene targeting have provided new insights, but also raise new questions concerning connexin function,

David L Paul