Midterm survival of a contemporary modular total knee replacement: a multicentre study of 1970 knees.

This retrospective study evaluated the midterm clinical and radiographic outcomes of a second-generation total knee replacement system. In a multicentre consecutive series of 1512 patients, 1970 knees were treated with the PFC Sigma knee system (Depuy, Warsaw, Indiana). The patients were reviewed for functional outcome, and underwent independent radiographic evaluation at a mean follow-up of 7.3 years (5 to 10). A total of 40 knees (2%) required revision, 17 (0.9%) for infection. The incidence of osteolysis was 2.2%. The ten-year survival with revision for any cause other than infection as the endpoint was 97.2% (95% CI 95.4 to 99.1). The PFC Sigma knee system appears to provide excellent results in the medium term.

Nonconstrained total shoulder arthroplasty in patients with polyarticular rheumatoid arthritis.

A retrospective review of 114 patients with polyarticular rheumatoid arthritis who had 140 total shoulder arthroplasties revealed that 93% of the patients had excellent pain relief; however, improvement in active forward elevation averaged 34 degrees. Nearly one-half of the patients had significant rotator cuff pathology. Three-fourths of the patients had a press-fit type of humeral component, and 5% of these have had variable amounts of subsidence. None have been sufficiently painful to require a revision. Eighty-two percent of the glenoid components developed radiolucent lines during the follow-up period. One percent of these were definitely loose and 9% were probably loose. To date, none have been revised. Complications occurred in 7% of the shoulders, but no deep or superficial wound infections were noted.

Glenoid loosening in total shoulder arthroplasty. Association with rotator cuff deficiency.

Seven cases of total shoulder arthroplasty exhibiting major glenoid radiolucent lines or actual translation of the glenoid component were evaluated to identify factors associated with glenoid loosening. The average time from arthroplasty was 30 months (range, 14-44 months). Six of the patients had severe, incompletely reconstructable rotator cuff tears present at the time of surgery, and one patient developed a cuff tear within 1 year of surgery. The amount of superior migration of the humeral component was closely correlated with the degree of glenoid loosening. With superior displacement of the humeral component, superior tipping of the glenoid component was observed: a "rocking horse" glenoid. For comparison, a contemporary group of 16 consecutive total shoulder arthroplasty patients with intact rotator cuffs were reviewed. The control group had no glenoid loosening an average of 5 years after operation. Upward riding of the prosthetic humeral head in patients with rotator cuff deficiency may contribute to loosening of the glenoid component in total shoulder arthroplasty.

Revision of failed unicondylar unicompartmental knee arthroplasty.

In a retrospective review of the cases of twenty-nine patients who had a revision of a failed unicondylar unicompartmental knee replacement, the cause of failure of the original unicondylar arthroplasty was found to be loosening of one or both components in sixteen patients, progression of disease in the opposite compartment in nine, patellofemoral symptoms in two, ligamentous instability in one, and malposition of the tibial component in one. A technical error had been made in sixteen of the patients, and ten of the errors were associated with the ultimate failure of the original unicondylar procedure. Ninety-three per cent of the failed unicompartmental arthroplasties were revised using a posterior cruciate-sparing total knee replacement. Bone grafts, augmentation with screws and cement, a long-stem component, or a combination of these were used in half of the patients. The average follow-up after the revision arthroplasty was 4.6 years.

Synovectomy of the rheumatoid knee using intra-articular injection of dysprosium-165-ferric hydroxide macroaggregates.

One hundred and eleven patients who had seropositive rheumatoid arthritis and persistent synovitis of the knee were treated with intra-articular injection of 270 millicuries of dysprosium-165 bound to ferric hydroxide macroaggregates. A two-year follow-up was available for fifty-nine of the treated knees. Thirty-nine had a good result; nine, a fair result; and eleven, a poor result. Of the twenty-five knees that had Stage-I radiographic changes, nineteen had a good result. Of the thirty-four knees that had Stage-II radiographic changes, twenty showed a good result. Systemic spread of the radioactivity from the injected joint was minimum. The mean whole-body dose was calculated to be 0.3 rad and that to the liver twenty-four hours after injection, 3.2 rads. The results indicated that dysprosium-165-ferric hydroxide macroaggregate is an effective agent for performing radiation synovectomy, particularly in knees that have Stage-I radiographic changes. Because of the minimum rate of systemic spread of the dysprosium-165, it offers a definite advantage over agents that previously have been used.

Total shoulder arthroplasty.

A prospective study was done of fifty total shoulder replacements in forty-four patients who were followed for an average of 3.5 years (range, 2.0 to 7.5 years). The preoperative diagnosis was osteoarthritis in thirty-three shoulders, rheumatoid arthritis in eleven, and a previous fracture of the humeral head in six shoulders. Nine of the shoulders had a tear of the rotator cuff. The Neer-II system of total shoulder replacement with a non-metal-backed component was used in all fifty shoulders. At follow-up, forty-four shoulders (88 per cent) had no significant pain. Of the six painful shoulders, four had loosening of the glenoid component and one had malposition of both components. Three of the six shoulders had no significant pain after revision. The average range of active forward elevation in all of the shoulders improved from 71 to 100 degrees, and both external and internal rotation improved as well. Five specific activities of daily living were evaluated, and the patients' ability to perform them improved from 14 to 78 per cent. Thirty-five shoulders (68 per cent) were rated by the patients as much better; thirteen shoulders (26 per cent), as better; and three (6 per cent), as no better. An incomplete lucent line was noted around five (10 per cent) of the cemented humeral stems and around thirty-seven (74 per cent) of the glenoid prostheses. Four arthroplasties (8 per cent) required revision: three for loosening of the glenoid component and one for malposition of both components.(ABSTRACT TRUNCATED AT 250 WORDS)

The effectiveness of the Salter innominate osteotomy in the treatment of congenital dislocation of the hip.

A retrospective review of sixty-eight innominate osteotomies that were performed in fifty-four patients at a university teaching hospital was undertaken to compare the results of these operations with those published by Salter and by his colleagues and to see if the results were different when the procedure was combined with open reduction compared with when it was performed after open reduction. Over-all, nearly three-quarters of the patients had excellent or good radiographic and clinical results. Avascular necrosis occurred in four patients after open reduction and innominate osteotomy. Postoperatively, eight complications developed in seven patients. Innominate osteotomy improved coverage of the femoral head. There was no noticeable difference between the results of innominate osteotomy combined with open reduction and those of innominate osteotomy performed after a previous open reduction. The patients who had an open reduction combined with innominate osteotomy before the age of four years had better results and required fewer subsequent procedures than did patients who had the operation after that age.

Fracture separation of the distal humeral physis in the newborn.

Fracture separation of the distal humeral physis in the newborn is a rare injury. Two case reports are presented, both with a history of traumatic delivery and a clinical examination revealing swelling, hypermobility, and muffled crepitance about the elbow. Radiographs demonstrated posteromedial displacement of the distal humeral epiphysis with respect to the shaft. Closed reduction with splint immobilization is the most common form of treatment.