This study compares the PFC total knee arthroplasty (TKA) system in a prospective randomized control trial (RCT) of the mobile-bearing rotating-platform (RP) TKA against the fixed-bearing (FB) TKA. This is the largest RCT with the longest follow-up where cruciate-retaining PFC total knee arthroplasties are compared in a non-bilateral TKA study. A total of 167 patients (190 knees with 23 bilateral cases), were recruited prospectively and randomly assigned, with 91 knees receiving the RP and 99 knees receiving FB. The mean age was 65.5 years (48 to 82), the mean body mass index (BMI) was 29.7 kg/m2 (20 to 52) and 73 patients were female. The Knee Society Score (KSS), Knee Society Functional Score (KSFS), Oxford Knee Score (OKS), Western Ontario and McMaster Universities Arthritis Index (WOMAC), and 12-Item Short-Form Health Survey Physical and Mental Component Scores (SF-12 PCS, SF-12 MCS) were gathered and recorded preoperatively, at five-years’ follow-up, and at ten years’ follow-up. Additionally, Knee Injury and Osteoarthritis Outcome Scores (KOOS) were collected at five- and ten-year follow-ups. The prevalence of radiolucent lines (RL) on radiographs and implant survival were recorded at five- and ten-year follow-ups.Aims
Patients and Methods
The purpose of the current study was to compare the results of the P.F.C. Rotating Platform Knee System and the P.F.C. Knee System in a randomised prospective study. 151 patients were enrolled in the study, totalling 172 knees, with 84 receiving fixed bearing and 88 receiving rotating platform knees. Patients were enrolled prospectively with preoperative assessment of the defined outcome measures including Knee society score, Oxford Knee Score, SF-36 score, WOMAC score, VAS pain score and ROM. These outcome measures were repeated at 6 months, 1 year and 2 years At the two year follow up patients were assessed and results analyzed to see if there were any significant differences with regard to outcome measures. There was no statistically significant difference for the SF12, Oxford knee score or the VAS pain score. In the Knee Society Score a trend effect at the one year follow up (almost significant at p = 0.07) was seen with the rotating group scoring better in overall function than the fixed group. At the two year follow-up this difference between groups became significant (p = 0.05) and the rotating group had significantly better overall function than the fixed group. The early results show a better functional score with comparable subjective outcome measures with regard to pain and ROM. The long term purported benefits of the rotating platform versus fixed will be watched with interest in the medium to long term follow up.
We report a case of septic arthritis of the hip caused by toxigenic Corynebacterium diphtheria in a healthy, immunized child. A four-year-old boy was admitted to our hospital with a four-day history of right thigh pain, inability to bear weight on the right leg and sore throat of one-day duration. He was born in New Zealand and had been immunized against diphtheria. On admission he was febrile (37.3°C) with a congested throat. The right hip was flexed and externally rotated. His inflammatory markers were elevated. Aspiration of the hip yielded 8ml of yellow turbid fluid. Gram stain showed gram-positive bacilli. An arthrotomy was performed and the hip drained Cultures of the aspirate grew Corynebacterium diphtheriae, the toxigenicity confirmed by the national reference laboratory. The patient was treated with intravenous and oral antibiotics for 6 weeks and he made a full recovery. Our patient had a history of immunization to diphtheria and this induces a protective level of antibodies against the toxin but does not prevent the bacteria from invading the blood stream and causing infection. This is to our knowledge the first reported case of septic arthritis caused by toxigenic strain of Corynebacterium diphtheria.
Treatment of displaced intracapsular fracture of the hip by hemiarthroplasty in old patients is generally satisfactory. Middlemore Hospital’s agreed criteria for hemiarthroplasty were reviewed and tested. Two hundred and thirty three patients who had hemiarthroplasty for displaced intracapsular fracture neck of femur between June 199- June 2001. All the patients’ data collected from the hospital computer system and then a search started for these patients to review their current status regarding pain and mobility. Ninety nine patients (42%) were still alive, of them 13 demented, 13 moved or lost and 7 in a wheel chair. Sixty six patients reviewed for pain and mobility using Sikorski and Barrington scoring criteria for pain and mobility. Thirteen patients had painful hemiarthroplasty. Clinical notes of the most active group of these patients (7 patients) reviewed individually to identify the causes. Two patients had revision to total hip joint replacement within 3 months because of technical errors and two patients placed on the waiting list for revision. The rest had deterioration in their general health that made total hip arthroplasty a risky operation for them. The revision rate was 1.7 %. We concluded that hemiarthroplasty was an acceptable option for these patients. The selection criteria were correct in 98.2% of the cases. Patients who live in their own home will need a careful assessment before deciding on a hemiarthroplasty for them.
