Lateral patellar contact after total knee arthroplasty: an analysis of the effects on postoperative pain and outcome.

Although medialization of the patellar component during primary total knee arthroplasty (TKA) has been advocated for biomechanical reasons, this can lead to lateral patellar contact with the femoral component. Using blinded radiographic evaluations, we evaluated 980 consecutive primary TKAs performed from 1997 to 1998. The prevalence of lateral patellar contact in this series was found to be 46.1%. Lateral patellar contact was not correlated with significant differences in our measures of outcome (knee score [P = .1066], functional score [P = .2457], or range of motion [P = .2514]). The average pain score in knees with lateral patellar contact was higher (48.1) (less pain) when compared with knees without (46.7). Total knee arthroplasties without lateral patellar contact had a 1.61 times odds of experiencing postoperative pain compared with those TKAs with lateral patellar contact (P = .0025).