The contributions of muscles and reflexes to the regulation of joint and limb mechanics.

The property of muscular stiffness is essential to the regulation of posture and interjoint coordination. The mechanical properties of a skeletal muscle arise from the integration of sensory feedback with the intrinsic mechanics of the muscle. Damage to peripheral nerves and probably the muscle itself can result in a permanent loss of sensory feedback with consequent alterations in muscular stiffness and interjoint coordination. Additional study of neural feedback, its vulnerability to damage, and the means to promote its recovery after muscular damage is an important direction for the investigation and treatment of musculoskeletal disorders.