Annual Meeting Abstracts: D-24 – Free Communication/Poster: Athlete Care: Lower Extremity
Total knee arthroplasty (TKA) is a surgical intervention for pain relief and restoration of mobility in individuals with osteoarthritis (OA). PURPOSE: To evaluate knee joint, knee extensor skeletal muscle, and physical functional performance before and after TKA. METHODS: Candidates for TKA (TKA; n = 13) and age, sex, and height-matched controls (CON; n = 13) were compared prior to surgery, 1 and 3 months post-surgery. Outcome measures included use-related knee pain, functional range of motion (FROM:peak flexion-extension), knee extensor muscles isometric peak torque (IVCpeak), knee extensor muscles activation (CAR = voluntary torque/(voluntary + electrical stimulation torque) * 100), torque per cross sectional area (torque/CSA) of the knee extensor muscles, leg extensor muscles power (LEP), number of steps/day, and physical functional performance (Continuous-scale Physical Functional Performance Test: Cs-PFP). RESULTS: At baseline, in the surgical limb, TKA patients reported significantly higher (p<0.05) use-related knee pain than controls (TKA: 2.63 ± 2.6, CON: 0.02 ± 0.1) and were significantly lower (p<.05) on all other outcomes of FROM (TKA: 107.60 ± 16, CON: 139.80 ± 6), IVCpeak (Nm, TKA: 83.3 ± 41, CON: 182.2 ± 65), CAR (%, TKA: 86.5 ± 9, CON: 96.8 ± 3), LEP (watts, TKA: 92.6 ± 58, CON: 239.5 ± 108), torque/CSA (Nm/cm2, TKA: 1.78 ± 0.7, CON: 3.01 ± 0.6), steps/day (TKA: 3,954.3 ± 2,616, CON: 8,282.4 ± 3,037), and Cs-PFP (TKA: 49.2 ± 15, CON: 78.7 ± 15). One-month post-surgery, in the surgical limb, the TKA group reported decreased use-related pain of 82% and increased muscle activation by 12% (p<.05). From 1-to- 3 months post-surgery, the TKA surgical limb FROM increased by 13%, IVCpeak by 16%, LEP by 55%, torque/CSA by 13%, and steps/day by 46% (p<.05). Concurrent to these changes, Cs-PFP improved 19% (p<.05). Change in functional range of motion in the surgical limb explained 54% of the variance in recovery of physical functional performance. CONCLUSIONS: These data indicate physical functional performance is significantly compromised in individuals with OA prior to TKA surgery. TKA relieves pain after which joint function, quadriceps muscles function, physical functional performance, and physical reserves are restored. Supported by 2003 Georgia Gerontology Seed Grant (JKP), Athens Orthopedic Clinic Foundation Award (JKP), and in part by HD 39676 (GAD) and HD 37439 S1 (GAD).