Table 1.

Grades of tennis leg

Grade	Symptoms	Signs	Pathologic findings	Radiologic findings
Grade 1 (mild)	Sharp pain at time of injury or pain with activity. Usually able to continue activity	Mild pain and localized tenderness. Mild spasm and swelling. No or minimal loss of strength and range of motion	<10% muscle fibers disrupted	Bright signals on fluid‐sensitive sequences. Feathery appearance < 5% muscle fiber involvement
Grade 2 (moderate)	Unable to continue activity	Clear loss of strength and range of motion	10%–50% disruption of muscle fibers	Change in myotendinous junction. Edema and hemorrhage
Grade 3 (severe)	Immediate severe pain, disability	Complete loss of muscle function. Palpable defect or mass	50%–100% disruption of muscle fibers	Complete disruption of continuity of muscle. Extensive edema and hemorrhage. Wavy tendon morphology and retraction