Medical Disclaimer
The information on this page is for educational purposes only and is not intended to replace professional medical advice, diagnosis, or treatment.
Always seek the advice of your doctor or other qualified health professional with any questions you may have regarding a medical condition.
🚨Emergency? If you have severe symptoms, difficulty breathing, or think it's an emergency, call 000 immediately.
Inner Knee Pain (Pes Anserine Bursitis)
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 is Inner Knee Pain (Pes Anserine Bursitis)?
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 Causes It?
- Repetitive friction between hamstring tendons and underlying bursa
- Overuse from running or cycling (especially sudden increase in training)
- Knee valgus (knock-knee) alignment increasing stress on medial knee
- Obesity (increased loading on medial knee structures)
- Tight hamstrings pulling on pes anserine insertion
- Osteoarthritis of knee altering gait mechanics and overloading pes anserine
- Diabetes (association with pes anserine bursitis—unclear mechanism but well-documented)
⚠️Risk Factors
You may be at higher risk if:
- Female gender (2-3 times more common than males)
- Age 40-60 years (peak incidence in middle-aged women)
- Obesity (BMI more than 30)
- Knee osteoarthritis (30-40% have concurrent pes anserine bursitis)
- Diabetes mellitus (increased risk, unclear mechanism)
- Knee valgus (knock-knee) alignment
- Distance running (especially runners increasing mileage rapidly)
- Hamstring tightness
- Flat feet (pes planus) causing increased knee valgus during gait
🛡️Prevention
- ✓Maintain healthy weight (reduces medial knee loading)
- ✓Regular hamstring stretching (before and after exercise)
- ✓Hip and quadriceps strengthening (improves knee biomechanics)
- ✓Gradual increase in training volume (avoid sudden mileage increases in running)
- ✓Proper footwear and orthotics if flat feet causing knee valgus
- ✓Address knee valgus with gait retraining and strengthening