Hip Muscle Atrophy Found Among Patients With Knee Arthritis
Patient’s with knee arthritis often experience pain with weight bearing activities including, standing, walking, stair climbing, and hiking. In our Physical Therapy practice, we find impairments of range of motion, gait deviations, balance, and strength within this patient population. In particular, weakness of the quadricep and hip musculature contributes to pain during weight bearing activities. The lower body muscles act as shock absorbers for the knee joint dissipating forces and reducing loads at the joint surface. Patients who regain their lost strength experience significantly less symptoms with the activities they enjoy.
A recent study in the journal Osteoarthritis and Cartilage examined the hip muscle volumes of patients with knee arthritis vs. their age matched peers (Ackland et al. 2018). Patients and controls all underwent a gait analysis, as well as, a MRI to determine the muscle volume of their gluteus medius, gluteus minimus, and TFL (tensor fascia lata) musculature. Authors noted significantly smaller hip musculature in patient’s with knee arthritis compared to their age matched peers. In addition, muscle atrophy was associated with abnormal gait mechanics. There is currently evidence for both the development of weakness after the onset of knee pain, as well as, evidence documenting weakness as an independent risk factor for the development of knee pain. Patient’s with knee arthritis are encouraged to utilize Physical Therapy interventions to regain their lower body strength in order to optimize their participation in the activities they enjoy.