[Muscle strength analysis of patella resurfacing in total knee arthroplasty].

Objective: To investigate the influence of patella tracking and thickness for muscle strength after patellar resurfacing in total knee arthroplasty (TKA).

Methods: Quadriceps muscle strength of 100 cases 134 knees with osteoarthritis were analysed with isokinetic testing and extension lag after patellar resurfacing in TKA. Result was analyzed statistically through T test.

Results: Significant decreasing of quadriceps muscle strength and endurance were detected on mal-patellofemoral tracking (61 +/- 24, P <0.01) and improper position of patella prosthesis (56 +/- 33, P < 0.01). Anterior knee pain with patella resurfacing was mainly associated with mal-patellofemoral tracking.

Conclusion: Asymptomatic weakness of quadriceps muscle was mainly associated with improper patella thickness.