Rotating hinge total knee arthroplasty in severly affected knees.

A consecutive series of 24 knees in 21 patients who received a Finn rotating hinge for primary (nine knees) or revision (15 knees) total knee arthroplasty between August 1993 and January 1997 was reviewed. The average followup was 33 months (range, 21-62 months) for all patients in the study. Seventeen patients (20 knees) were followed up for more than 2 years. Twenty-four knees (21 patients) were categorized according to Knee Society scoring criteria: 37.5% (nine knees) were Category A, 25% (six knees) were Category B, and 37.5% (nine knees) were Category C. Using the Knee Society knee and function scores, clinical and radiographic results were assessed and outcome analysis was determined. The average Knee Society knee score improved from 44 points (range, 5-64 points) before surgery to 83 points (range, 45-95 points) after surgery; the average functional score according to the Knee Society system improved from 10 points (range, 0-35 points) before surgery to 45 points (range, 0-100 points) after surgery. Pain and function markedly improved after surgery. For treatment of the most severely affected knees with compromised bone and ligamentous instability, the Finn total knee replacement appears to be an acceptable option. As a rotating hinge design, the prosthesis at early followup provides excellent pain relief, restoration of walking capacity, and stabilization, without evidence of early mechanical failure.

Patella height after high tibial osteotomy with internal fixation and early motion.

The purpose of this study was to compare the incidence of patella infera in patients after high tibial osteotomy treated with either postoperative immobilization or internal fixation and early range of motion. A retrospective review of 98 patients with high tibial osteotomy was done at the authors' institution. Thirty-three patients who had secondary procedures such as concomitant ligamentous reconstruction with early motion were excluded. Therefore, 69 knees in 65 patients remained in the study cohort. Group A consisted of 32 patients (34 knees) treated with postoperative immobilization, whereas Group B included 33 patients (35 knees) treated with internal fixation and early motion. The preoperative and postoperative Insall-Salvati index, Blackburne-Peel index, and angular alignment were determined for each group. Between Groups A and B, the differences in the Insall-Salvati index and the Blackburne-Peel index were statistically significant, although the difference in angular correction was not significant. With rigid fixation and early motion the Insall-Salvati index showed that there was less postoperative shortening of the patellar tendon. The relationship of the patella to the remainder of the knee was affected less adversely as evidenced by the Blackburne-Peel index. High tibial osteotomy with internal fixation and early range of motion should result in a better knee and ease the subsequent performance of a total knee arthroplasty.

Cardiac arrest as a result of intraabdominal extravasation of fluid during arthroscopic removal of a loose body from the hip joint of a patient with an acetabular fracture.

The case of a fifty-year-old man who suffered an isolated, associated, both-column fracture of the left acetabulum is presented. He underwent an uncomplicated open reduction and internal fixation through an ilioinguinal approach. A follow-up computed tomographic scan was performed postoperatively, which documented intraarticular fragments. Hip arthroscopy was performed to remove the fragments. During the procedure, arthroscopic fluid extravasated through the fracture site under pump pressure and resulted in an intraabdominal compartment syndrome that presented as cardiopulmonary arrest. An emergent exploratory laparotomy was performed to release the fluid and resume blood flow. Despite prolonged asystole, the patient survived without neurologic sequelae. The literature on compartment syndrome secondary to arthroscopic procedures is reviewed. Because of this previously unreported potentially lethal complication, we do not advocate hip arthroscopic procedures for acute or healing acetabular fractures.

Subclinical slipped capital femoral epiphysis. Relationship to osteoarthrosis of the hip.

We examined the femora of 2665 adult human skeletons from an osteological collection to determine the prevalence of post-slip morphology termed femoral head-tilt deformity by Murray and pistol-grip deformity by Stulberg et al. The hypothesis was that primary osteoarthrosis of the hip is a secondary manifestation of a subclinical developmental disorder of the hip. The prevalence of post-slip morphology was 8 per cent (215 of 2665 skeletons). Severe osteoarthrosis was more prevalent in association with post-slip morphology (116 [38 per cent] of 306 hips) than in the matched controls (seventy-nine [26 per cent] of 306 hips) (p < 0.005). In the skeletons that had unilateral post-slip morphology, severe osteoarthrosis was more prevalent in the involved hips (thirty-one [37 per cent] of eighty-three) than in the contralateral, normal hips (eighteen [22 per cent] of eighty-three) (p < 0.05). Post-slip morphology, which was unrelated to age, was found to be a major risk factor for the development of high-grade osteoarthrosis. We noted evidence of high-grade osteoarthrosis in sixty-three (68 percent) of the ninety-three hips with minimum post-slip morphology in skeletons from individuals who had been fifty-six years old or more at the time of death compared with forty-five (48 percent) of the ninety-three control hips. This difference was significant (p < 0.025) [corrected]. The osteoarthrosis in the hips with post-slip morphology was distinctly characterized by anterior flattening of the acetabulum, cystic degeneration in the anterior metaphyseal-epiphyseal region, and progression to global osteoarthrosis of the hip.

Recent advances in total knee replacement surgery.

The evolution of total knee replacement designs and techniques has made possible predictable and long-lasting pain relief in the treatment of knee arthritis. Excellent long-term results have been obtained with cemented knee replacement, with or without preservation of the posterior cruciate ligament. Attempts to achieve similar results with cementless implants have been hampered by designs with thin polyethylene and high-contact stresses, leading to early failure. Unicompartmental replacement can be used in the treatment of focal arthritis in one compartment, but designs with thin polyethylene must be avoided. Low molecular weight heparin can be a useful adjunct to warfarin in the prevention of deep-vein thrombosis. Further studies must be made to lower the incidence of infection, mechanical failure, and wear-debris generation.

Total hip arthroplasty in cerebral palsy. Long-term follow-up results.

Patients with cerebral palsy frequently develop coxarthrosis after acquired hip dislocation or dysplasia. Nineteen total hip arthroplasties (THA) were performed in 18 patients with cerebral palsy and end-stage hip degeneration. The average age at arthroplasty was 30 years (range, 16-52 years). All components were cemented, and four hips required bone graft augmentation of the deficient acetabulum. Spica casts were used in 16 of 18 patients to minimize the incidence of dislocation and trochanteric nonunion. The average follow-up time was ten years (range, three to 17 years). Seventeen of 18 patients (94%) had pain relief and improved function after arthroplasty. One stem loosened at three years, and one acetabular component loosened at 15 years. One stem and one acetabular component were revised for malposition. Survivorship analysis was 95% at ten years for loosening and 86% with removal for any reason. Total hip arthroplasty can provide long-term relief and improved function in cerebral palsy patients with severe coxarthrosis.

Titanium wear debris in failed cemented total hip arthroplasty. An analysis of 71 cases.

Seventy-one cemented total hip arthroplasties (THAs) were reviewed following removal of the all-titanium alloy femoral stem. Fifty-one hips were primary arthroplasties that failed due to aseptic loosening, 8 were previous revisions with aseptic loosening, and 12 were removed for infection. The average duration of service for the three groups was 4.5 years, 5.0 years, and 3.7 years, respectively. Femoral bone loss in aseptically loose, primary THA was graded as severe in 51%, moderate in 24%, and mild in 20%. Femoral endosteolysis was present in 94%, while acetabular osteolysis was seen in 6%. Histological evaluation of tissues from failed primary arthroplasties revealed polymethyl methacrylate debris in 75% of cases, polyethylene debris in 80%, metal debris in 75%, and chronic inflammatory cells in all cases. Metallic debris was not seen in the failed revision cases and in only 17% of the infected cases. Examination of retrieved femoral components revealed burnishing of the head in all cases, while 71% of stems with aseptic loosening were abraded from the cement. Metal levels from 12 cases averaged 2,111 mg/g of dry tissue (range, 60-11,823); synovial fluid levels from 8 other cases averaged 106 mg/l (range, 22-340). While it is not certain whether metallic particles are a primary cause of loosening or are generated secondarily, their presence seems to accelerate bone loss and loosening.

Wear debris in cemented total hip arthroplasty.

One of the most prevalent clinical problems in long-term follow up of total hip arthroplasty patients is loosening of prosthetic fixation. Factors contributing to mechanical failure of total hip reconstruction are complex and multiple. It has become increasingly apparent that wear debris from the prosthetic components may contribute significantly to this process. The authors summarize some of the current concepts concerning the detrimental effects of metallic debris in total hip arthroplasty.

Bilateral femoral retroversion associated with acetabular dysplasia. A case report.

Retroversion of the proximal femur is associated with a number of acquired conditions but is unusual in a congenital form. It is even more unusual to be associated with acetabular dysplasia. A 38-year-old woman with bilateral hip pain had roentgenographic evidence of acetabular dysplasia with valgus neck-shaft angles. Physical findings were consistent with femoral retroversion, and computed tomography demonstrated 28 degrees of retroversion on both sides. Symptomatic relief was obtained with bilateral varus internal rotation osteotomies of the proximal femur. To date, a case of retroverted femora associated with acetabular dysplasia seems not to have been reported in the literature.