Should the patella be resurfaced during total knee replacement?

Patellar resurfacing during total knee replacement (TKR) has been a controversial subject for many years. In 1990 a randomised prospective study was started to compare policies of resurfacing, not resurfacing and selectively resurfacing the patella. One hundred and twenty-five cases (suitable for a cruciate sparing TKR) were randomised. At the 5-year review, the group in which the patella had not been resurfaced had needed significantly more secondary surgery than the other groups. Global knee scoring systems showed little difference between the groups but a scoring system which focused on the patella revealed differences and demonstrated worse results when the patella was not resurfaced. A minor degree, of maltracking was tolerated in resurfaced knees but tended to cause pain and articular cartilage wear in unresurfaced patellae. Four knees with good patellar articular cartilage at surgery did poorly when not resurfaced, suggesting that a selective policy is not totally reliable. Routine patellar resurfacing gave the most reliable results.