Comparison of knee extensor strength between limbs in individuals with bilateral total knee replacement.

Abstract

To determine and compare force production of the knee extensors between limbs after bilateral total knee arthroplasty (TKA). Two repeated-measures designs (2 factors: limb, time) assessing for differences in strength between limbs over 3 times at 2 different testing speeds. Private and institutional practice. Fourteen volunteers (6 men, 8 women; mean age +/- standard deviation, 74.57 +/- 5.5 y; height, 169.91 +/- 9.43 cm; weight, 76.42 +/- 9.85 kg) with bilateral TKA. Open-chain knee extensor strength was measured in both legs before surgery and 30 and 60 days after TKA at 60 degrees /s and 180 degrees /s. Rehabilitation 3 times weekly for 8 weeks. Treatment consisted of gait, transfer training, stationary cycle work, and a progressive resistance-training program. Peak torque measured isokinetically. Limb by time interaction was not significant for either 60 degrees /s (F(2,26) =.75, P =.351) or 180 degrees /s (F(2,26) =.78, P =.393). A significant main effect of time was found at 60 degrees /s (F(2,26) = 14.22, P =.0001) and 180 degrees /s (F(2,26) = 10.47, P =.003). During the first month after TKA, bilateral knee extensor force-production decreased significantly compared with preoperative force production.