A reduced range of movement post total knee replacement (TKR) surgery is a well recognised problem. Manipulation under anaesthesia (MUA) is a commonly performed procedure in the stiff post operative TKR. Long term results have been variable in the literature. We prospectively followed up 48 patients since 1996 from one centre, over an average of 7.5 years, (range 1 to 10 years) and report on the long term results. The mean time to MUA post TKR was 12.3 weeks (range 3 to 48). Pre MUA, the mean flexion was 53°. The mean immediate passive flexion post MUA was 97°, an improvement of 44° (Range 10° to 90°, CI < 0.05). By one year, the mean flexion was 87°, improvement of 34°, (range −15° to 70°, CI< 0.05). At ten years the mean flexion was 86°. We found no difference between those knees manipulated before or after 12 weeks. In addition there was no difference found in those knees which had a pre TKR flexion of greater or less than 90°. There were no complications as a result of MUA. However, one patient was eventually revised at two years secondary to low grade infection. Our findings show that MUA is safe and effective method at improving the range of motion in a stiff post operative TKR. The improvement is maintained in the long term irrespective of time to MUA and range of motion pre TKR
We have prospectively followed 100 consecutive HA coated knee replacements performed from 1990–1992. The prostheses was a cruciate sacrificing IB II, with HA coating on the femoral and tibial components. The average age at surgery was 72.5 years [32–92]. The indications for surgery was predominantly osteoarthritis [93 cases]. 3 knees required cemented tibial components at surgery and were excluded from the series. All knees were mobilised full weight bearing postoperatively. Patients were reviewed annually with radiographic and clinical evaluation [Hospital for Special Surgery Knee score]. There was no loss to follow-up and at most recent review 48 people [60 knees] were alive. Of these, 47 knees had a final radiographic examination; the remaining knees were assessed clinically but did not attend hospital. Using revision or need for revision as the endpoint for failure, 6 knees have been revised giving a 10 year survival of 92% [CI 0.96–0.76]. 3 tibial and 2 femoral components underwent aseptic loosening. 1 revision was for infection and 1 for technical errors. Using pain as the endpoint for survival, 5 surviving knees [9.3%] complained of moderate or severe pain at rest or during exercise and could be regarded as failures. There is a very low incidence of radiolucent lines at the prostheses-bone interface with 11 radiolucent zones of <
1mm under the tibial component [knee society radiological evaluation]. 72% of cases demonstrated evidence of bone-prostheses bonding with ‘spot welds’ or buttress formation. Overall the survival at ten years is comparable with cemented fixation. We believe the evidence of bone-prostheses bonding and absence of radiolucent lines indicates that the surviving knees will continue to function well.