Differential strength decline in patients with osteoarthritis of the knee: revision of a hypothesis

Open Access
Publisher Website
Google Scholar
Abstract
A quadriceps-to-hamstring isometric peak torque ratio (Q/H ratio) of approximately 2.0 is considered necessary for appropriate knee biomechanics. Lower ratios may affectthe function of persons with osteoarthritis (OA) and the progression of the disease. This study examined theisometric Q/H ratio in subjects with and without OA of the knee and explored the effect of age, pain, and joint enlargement on the ratio. Twenty-one pairs of subjects (OA, control) were matched on age (X = 62.6 years; SD = 13.9), gender (F = 17, M = 4), and leg dominance (Dominant = 10, Nondominant = 11). Isometric quadriceps and hamstring peak torque, knee pain, and joint enlargement were measured. Paired t-tests demonstrated that the OA group had significantly lower quadriceps peak torque than the control group but did not have significantly lower hamstring peak torque or gravity-corrected isometric Q/H ratio. Age correlated with the ratio in subjects without OA (p = −0.46; P = 0.03) but not in subjects with OA. Pain was not significantly correlated with the ratio in either group. Joint enlargement correlated with the ratio in the OA group (p = −0.45; P = 0.03). The gravity-corrected isometric Q/H ratio appears to decrease with age in subjects without OA. In subjects with OA, the Q/H ratio appears not to change with disease, pain, or age. Joint enlargement may decrease the ratio and merits further study.