Patellectomy after total knee arthroplasty

We retrospectively reviewed nine patients who had condylar TKA and subsequently had a patellectomy between 1969 and 2003. One patient was lost to followup, but the remaining eight patients were followed up for an average of 49 months after patellectomy. All patellectomies were done after comminuted patellar fractures at an average of 21 months (range, 4-88 months) after the initial arthroplasty. Knee scores after the initial arthroplasty were 83 points (range, 69-97 points) and 49 points (range, 10-100 points) for pain and function, respectively. Knee scores after patellectomy were 81 (range, 20-97) and 28 (range, 0-80) for pain and function, respectively. The average range of motion before and after patellectomy was 0 degrees to 104 degrees and 2 degrees to 106 degrees , respectively. Four patients had mild extensor lags at final examination, but all were less than 10 degrees . Two patients were unable to use stairs. Two patients had complications consisting of quadriceps tendon rupture and secondary instability. Midterm results after patellectomy show knee scores for pain that are comparable to those after initial arthroplasties, but the function scores were not as good. Fifty percent of the patients had extensor lags but all were mild (< 10 degrees ). Patellectomy can provide pain relief after a patellar fracture after total knee arthroplasty but the functional results are frequently poor.

Therapeutic study, Level IV-1 (case series). See the Guidelines for Authors for a complete description of levels of evidence.