TABLE 1.

Characteristics of Acute Hamstring Strain and Proximal Hamstring Tendinopathy

	Acute Hamstring Strain	Proximal Hamstring Tendinopathy
Mechanism	Type I – high-speed running Type II – overstretch	Mechanical overload, repetitive stretch
Most common location	Type I – proximal muscle-tendon junction Type II – proximal free tendon of semimembranosus	Semimembranosus
Presentation	Sudden onset “Pop” (primarily type II) Difficulty continuing sport	No specific inciting event Gradual increase of pain
Physical Examination	Ecchymosis +/− palpable defect Pain and/or weakness with hip extension, knee flexion testing	Puranen-Orava test Bent-knee stretch test (modified) Tenderness at ischial tuberosity No loss of strength
Imaging	Not necessary for diagnosis X-ray if suspect ischial avulsion injury	MRI or ultrasound. MRI with higher sensitivity.
Conservative Treatment	Phase I – decrease pain and edema, RICE protocol Phase II – increase exercise, neuromuscular training, initiate eccentric exercises Phase III – sport-specific exercises	Eccentric exercises Graduated return to activity protocol Shockwave therapy Soft-tissue mobilization
Injections	Corticosteroids – minimal evidence Platelet-rich-plasma – mixed evidence	Corticosteroids – minimal evidence, controversial Platelet-rich plasma – minimal evidence
Return to play	Faster recovery for Type I strains, shorter time to walk without pain	Full range of motion and no pain with strength testing required