Unicompartmental knee replacements have been performed since the 1970’s. Controversy still exists as to the indications and contra-indications for these procedures, and there is still no clarity as to whether the patient should have a high tibial osteotomy, a unicompartmental knee replacement, or a total knee replacement. It has been suggested that unicompartmental knee replacements are preferable to high tibial osteotomies, as conversion to a total knee replacement is easier following a unicompartmental replacement. Ten patients with unicompartmental knee replacements presented to the author requiring revision. All were revised to total knee replacements. In four a primary knee replacement could be performed, but the remaining six required a revision prosthesis on the tibial side, using stems and wedges. No revision prostheses were required on the femoral side. Revision of a unicompartmental total knee replacement is technically easier than the revision of a total knee replacement. Revision of a high tibial osteotomy to a total knee replacement can be difficult, particularly if a poorly performed HTO had been done, with residual significant ligament imbalance. The author feels that any type of revision surgery can be difficult. The author concludes that there is still no clarity as to whether one should do a unicompartmental knee replacement or a high tibial osteotomy, and that currently it is still the Surgeon’s choice as to which procedure he is going to perform.
Between February 2000 and August 2002, 60 Oxford unicompartment knee replacements were done on 51 patients, nine of whom had bilateral surgery. The mean age of patients, 82% of whom were women, was 66 years (45 to 83). Primary osteoarthritis was the pathology in 97% and post-traumatic arthritis in 3%. A full radiological assessment was done to determine positioning of the prostheses as well as the interfaces. The mean range of movement increased from 113° pre-operatively to 120° at the most recent follow-up. Complications included one case of deep venous thrombosis, one patient with bilateral tibial component loosening and three patients with loose cement particles in the joint. Most patients have no pain, but some have mild or occasional pain. One patient with bilateral unicompartmental replacements now has lateral knee pain. Unicompartment knee replacements are an alternative to total knee replacements, but there is a significant learning curve, particularly with regard to cementing techniques. Attention needs to be paid to removing all loose cement from the joint. Patient selection is critical. The complication rate remains low, however, and the results seem satisfactory.
From September 1995 to March 2003, 15 patellofemoral joint replacements were done on 13 patients. The mean age of the one man and 12 women was 62 years. Osteoarthritis was the reason for surgery in 13 of the 15 knees. In the other two it was post-traumatic arthritis. Three different products were used: Avon (eight), Link Lubinus (five) and LCS patellofemoral prostheses (two). One patient has subsequently been revised to a total knee replacement. Recommendations are made regarding selection of patients and implants.
Between February 2000 and August 2002, 60 Oxford unicompartment knee replacements were done on 51 patients, nine of whom had bilateral surgery. The mean age of patients, 82% of whom were women, was 66 years (45 to 83). Primary osteoarthritis was the pathology in 97% and post-traumatic arthritis in 3%. The mean range of movement increased from 113° preoperatively to 120° at the most recent follow-up. Complications included one case of deep vein thrombosis, one patient with bilateral tibial component loosening and three patients with loose cement particles in the joint. Most patients have no pain, but some have mild or occasional pain. One patient with bilateral unicompartmental replacements now has lateral knee pain. Unicompartment knee replacements are an alternative to total knee replacements, but there is a significant learning curve, particularly with regard to cementing techniques. Attention needs to be paid to removing all loose cement from the joint. Patient selection is critical. The complication rate remains low, however, and the results seem satisfactory.
Total knee arthroplasty (TKA) is done primarily for pain relief, and function improves when there is less pain. Greater understanding of the biomechanical functioning of the knee has led to an improvement in prosthetic implants. Surgical technique, which plays an important role in the overall outcome of TKA, has also improved over the years. Simultaneous bilateral total knee arthroplasty (SBTKA) is one of the latest techniques employed by arthroplasty surgeons. SBTKA has advantages and disadvantages, and there are clearly diverse reactions to it from surgeons treating patients with bilateral osteoarthritis. We reviewed 87 patients who underwent SBTKA and compared complications, costs and functional results with those of patients who underwent staged TKA. The same surgeon performed all the operations. There was strict adherence to a consistent preoperative, intraoperative and postoperative protocol. Our results showed that the complications of SBTKA are not significantly different from of staged TKA. SBTKA is definitely more cost-effective, and rehabilitation and function were the same as in patients who had a staged procedure.
We review our first 100 LCS rotating platform total knee arthroplasty (TKA) procedures. Done between July 1993 and December 1996, they are currently at four to seven year follow-up. The sample includes 100 TKAs done in 88 patients as unilateral or bilateral procedures. At operation the mean age of patients, 51% of whom were female and 49% male, was 67 years (47 to 84). The right side was replaced in 54% of cases and the left in 46%. Preoperative diagnoses included degenerative and post-traumatic osteoarthritis in 95 knees and rheumatoid arthritis in five. Two assessments are currently being carried out. They include the American Knee Society Clinical Rating Score, functional ability and radiographic evaluation of knee alignment and radiolucencies. Mean clinical and functional Knee Society ratings were 38 and 57 (sum 95 points) preoperatively and 88 and 84 (sum 172 points) postoperatively. Radiographs showed valgus alignment in 90 rays and varus alignment (1° to 7°) in 10. Limited areas of radiolucency were seen around three tibial components. Two cases have required revision, one for septic loosening and one to correct recurrent varus deformity.
