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Final Program


Final Program

669 - Isokinetic Quadriceps Weakness Is Associated with Higher Risk for Total Knee Arthroplasty

Friday, February 28, 2025
5:00 PM - 6:30 PM MST
Objectives: To assess whether lower quadriceps strength or higher antagonist hamstring coactivation is associated with risk for total knee arthroplasty (TKA) over 84-months.

Design: The Multicenter Osteoarthritis Study follows a cohort of older adults with or at risk of knee osteoarthritis. Maximal strength was defined as peak measurement on baseline isokinetic (60°/s) quadriceps strength testing over 4 trials. Antagonist hamstring coactivation was defined as the median overall hamstring surface EMG activity during quadriceps maximum voluntary contraction (MVC), standardized by the peak hamstring EMG levels during hamstring activation MVC (% of max). TKA was confirmed by medical records over 84-month follow-up. Sex-stratified logistic regression models adjusted for age, race, study site, BMI, history of knee injury or surgery. Analyses of coactivation predicting TKA controlled for strength to assess whether coactivation provided additional value beyond what strength predicted. Sensitivity analyses stratified by the stronger and weaker halves within each sex. Odds ratios were estimated comparing the highest with the lowest tertile of strength and coactivation respectively in each sex.

Results: The mean±SD age and BMI for women (N=1385) were 62.3±7.6 years and 31.0±6.0 kg/m2 respectively. Men (N=867) were 61.8±7.9 years and 31.0±5.7 kg/m2 respectively. Lower quadriceps strength was associated with greater odds of undergoing TKA in women (OR=2.67; 95%CI (1.76, 4.05)) and to a lesser extent in men (OR = 1.81 95%Cl (1.05, 3.13)). No significant associations were found between hamstring coactivation level and TKA in either sex (all p >0.05).

Conclusions:

These data demonstrate lower baseline quadriceps strength is longitudinally associated with elevated risk for TKA over 84 months in women to a greater extent than in men. Evidence did not support that antagonist hamstring coactivation was associated with risk for TKA over this period. Early identification of quadriceps weakness is important. Further studies should assess whether quadriceps strengthening can attenuate risk for TKA.