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Please ask a qualified health professional about symptoms, treatment decisions, or concerns about your own condition.
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Bones & Joints
Pes anserine bursitis is inflammation of the bursa (fluid-filled sac that reduces friction) located on the inner side of the knee about 5-7cm below the joint line, where three hamstring tendons (sartorius, gracilis, semitendinosus—collectively called pes anserinus meaning 'goose's foot' for their fan-like arrangement) attach to the shin bone (tibia), most commonly affecting middle-aged and older women (particularly those with obesity, osteoarthritis, or diabetes) and distance runners. The condition presents as localized tenderness and pain on the inside of the knee that worsens with stairs, prolonged sitting, or getting up from a chair, often mimicking medial meniscus tears or medial compartment arthritis but distinguished by point tenderness 5-7cm below the joint line (not at the joint line itself). Pes anserine bursitis develops from repetitive friction between the tendons and underlying bursa, exacerbated by knee valgus (knock-knee) alignment, hamstring tightness, or biomechanical overload from obesity or altered gait patterns. Diagnosis is clinical (point tenderness at pes anserine insertion site) with imaging rarely needed unless excluding other pathology. Treatment is almost always conservative: activity modification, ice, NSAIDs, physiotherapy for hamstring stretching and strengthening, addressing underlying biomechanics (orthotics, weight loss), with 80-90% achieving resolution in 4-8 weeks. Corticosteroid injections provide rapid relief if conservative management fails (85-90% success rate), with surgery rarely needed (excision of bursa only if chronic refractory cases not responding to 6-12 months of conservative treatment and injections).
What it is and why it happens
Pes anserine bursitis is inflammation of the bursa (fluid-filled sac that reduces friction) located on the inner side of the knee about 5-7cm below the joint line, where three hamstring tendons (sartorius, gracilis, semitendinosus—collectively called pes anserinus meaning 'goose's foot' for their fan-like arrangement) attach to the shin bone (tibia), most commonly affecting middle-aged and older women (particularly those with obesity, osteoarthritis, or diabetes) and distance runners. The condition presents as localized tenderness and pain on the inside of the knee that worsens with stairs, prolonged sitting, or getting up from a chair, often mimicking medial meniscus tears or medial compartment arthritis but distinguished by point tenderness 5-7cm below the joint line (not at the joint line itself). Pes anserine bursitis develops from repetitive friction between the tendons and underlying bursa, exacerbated by knee valgus (knock-knee) alignment, hamstring tightness, or biomechanical overload from obesity or altered gait patterns. Diagnosis is clinical (point tenderness at pes anserine insertion site) with imaging rarely needed unless excluding other pathology. Treatment is almost always conservative: activity modification, ice, NSAIDs, physiotherapy for hamstring stretching and strengthening, addressing underlying biomechanics (orthotics, weight loss), with 80-90% achieving resolution in 4-8 weeks. Corticosteroid injections provide rapid relief if conservative management fails (85-90% success rate), with surgery rarely needed (excision of bursa only if chronic refractory cases not responding to 6-12 months of conservative treatment and injections).