To our knowledge in medial unicompartmental knee arthroplasty (UKA) no study has specifically assessed the difference in outcome between matched gender groups. Previous unmatched gender studies have indicated more favourable results for women. 2 groups of 40 of either sex was determined sufficient power for significant difference. These consecutively were matched with both the pre-operative clinical and radiological findings. Minimum follow up of 2 years, mean follow-up 5.9 years. Mean age at operation was 71 years. In both groups, the mean IKS knee and function scores improved significantly (p< 0.001) post operatively. There were no significant differences were between the 2 groups. In both groups mean preoperative flexion was 130 degrees and remained unchanged at final follow-up. No significant differences in preoperative and postoperative axial alignment and in the number of radiolucent lines, between groups. With component size used there was a significant difference (p < 0.001) between the 2 groups. However the size of the femoral or tibial implant used was significantly related (p< 0.001) to patient height for both sexes. Radiolucent lines were more frequent on the tibial component, but were considered stable with none progressing. No revisions for component failure. 1 patient in each group developed lateral compartment degenerative change. Male group; one conversion to TKA for undiagnosed pain, three patients underwent reoperation without changing the implant. Female group; no implants were revised, and two patients required a reoperation. Kaplan-Meier 5-year survival rate of 93.46% (84.8; 100) for men and100% for women. The survival rate difference is not significant (p=0.28).Method
Results
It is documented in the literature the very good results of lateral unicompartmental knee arthroplasty (UKA) when the standard accepted indications are followed. In our experience these indications can be extended to include post-traumatic osteoarthritis (OA) with malunion secondary to tibial plateau fracture. We report our results concerning 15 UKAs in these particular situations. From 1985 to 2009, we performed 15 lateral UKAs in 15 patients for post traumatic OA secondary to malunion following a tibial plateau fracture. 7 were female and 8 male. The mean age of the patients at the time of the index procedure was 45±17 years and the mean delay from initial trauma was 5.4 years. The average follow-up was 108 months (range 12–265 months).Introduction
Material and methods
