Muscle Strains and Tears

Presentation

Strains are acute injuries to muscle-tendon units that result from overstretching or overexerting. Strains may occur in the trapezius or paravertebral muscles during a motor vehicle collision, with a whiplash-type injury to the neck. A strain can also occur in the anterior thigh, posterior hamstring group, groin, or gastrocnemius muscle while a person is accelerating, running, or playing in a sport such as tennis. There may be an insidious development of pain and tightness, which is worse with use and better with rest. With more severe injury, such as a bicep-tendon rupture, the pain may be immediate and disabling. Tears of the muscle belly tend to be partial, with sudden onset of pain and partial loss of function. Often a tear occurs with considerable bleeding, which can lead to remarkable hematomas, causing swelling at the site and dissecting along tissue planes to create ecchymoses at distant, uninvolved sites. Complete tears are more likely in the tendinous part of the muscle. They can produce immediate loss of function and retraction of the torn end, creating a deformity and bulge.