Why Do Quadriceps Shake Before Knee Replacement?
The quadriceps are the muscles at the front of your thigh. They help straighten your knee, support standing, and control movement when you walk or climb stairs.
Before knee replacement, arthritis-related pain, reduced activity, and muscle weakness may affect how well these muscles work. As a result, the quadriceps may shake during exercises or when you try to straighten your knee.
Muscle shaking does not always indicate atrophy. Muscle atrophy means a reduction in muscle size, while shaking may reflect fatigue, reduced strength, pain, or difficulty controlling movement.