Fifty-seven revision total knee arthroplasties were performed in our hospital using the TC3 system between 1995 and 1997. Twelve patients died. Forty-five patients were followed up for an average of 5.6 years (range 4 – 7 years). No patients were lost to follow-up. All patients were clinically and radiologically evaluated. A postal patient satisfaction questionnaire was completed. Two patients were revised; one for infection and one for instability. Survivorship using revision as the end point was 93.3% at 7 years. Indications for revision were infection(4;9%), instability(38;84%), pain and stiffness(3;7%). 32(71%) patients were satisfied with their outcome, 7(16%) were non-committal and 6(13%) were disappointed at 5 years. We have analysed the 13 dissatisfied patients and highlight the lessons learnt.
Pain and stiffness are not good indications for revision. Insert thickness of more than 17.5mm is suggestive of elevation of the joint-line. Instead the femoral component should be distalised. Step wedges should be used in preference to angular wedges. Always long stem the tibial implant if augments are used. Stems should be canal filling with adequate grip on the diaphysis. We suggest the above lessons we have learnt from our initial revision arthroplasty learning curve may correlate to the clinical outcome of this small group of dis-satisfied patients.
