Abstract
Purpose
The aim of this study was to compare the short-term and mid-term outcome of lateral UKRs using a single prosthesis, the AMC Uniglide knee implant.
Methods
Between 2003 and 2010, seventy lateral unicompartmental knee replacements (mean patient age 63.6±12.7 years) were performed at our unit for isolated lateral compartmental disease. Range of knee motion and functional outcome measures including the American Knee Society (AKSS), Oxford (OKS) and WOMAC scores were recorded from 19 knees at five years' post-operatively and compared to 35 knees at two-years and 53 knees at one-year post-op.
Results
Mean range of motion at five-years post-op was 116° compared to 117° at two-years and 115° at one-year. Median AKSS was 177, 185 and 180 at 1, 2, and 5 years post-op with respective OKS of 39, 43, and 37. Total WOMAC scores were 19, 15 and 22 at 1, 2 and 5 years respectively. One-way ANOVA showed no significant decline in range of motion or functional outcome scores with increasing time since surgery (p>0.05). No lateral UKR required revision up to 5 years post-op.
Conclusion
This study demonstrates that at five years' post-op, patients who have undergone a lateral compartmental knee replacement for lateral compartment osteoarthritis using this prosthesis maintain an acceptable range of knee motion and knee function. Revision rates for the lateral UKR were excellent at 5 years following surgery. The lateral fixed bearing UKR demonstrates good short and medium term results for treating isolated lateral compartmental osteoarthritis and should be a consideration when managing patients with a pattern of lateral compartment disease.
