Pes Anserine Bursitis

Lower Limb

Overview

Pes anserine bursitis is inflammation of the bursa located between the pes anserinus tendons (sartorius, gracilis, semitendinosus) and the medial tibia, typically presenting with anteromedial knee pain. It is common in athletes, individuals with obesity, and those with biomechanical dysfunction such as knee valgus or excessive tibial internal rotation. The condition is usually self-limiting with appropriate conservative management including activity modification and addressing underlying causative factors.

Pathophysiology

The pes anserine bursa serves as a buffer between the three conjoined tendons and the underlying bone and medial collateral ligament. Repetitive friction from these tendons, particularly during activities involving knee flexion and hip internal rotation, leads to bursal inflammation and fluid accumulation. Contributing factors include tight hip internal rotators, weak hip abductors (gluteus medius insufficiency), excessive knee valgus, tibial internal rotation, increased body mass index, and activities involving running or climbing stairs. Chronic inflammation can develop from prolonged mechanical irritation without proper rehabilitation.

Typical Presentation

Site

Anteromedial knee, approximately 4-6 cm below the joint line, at the insertion point of the pes anserinus

Quality

Dull, aching pain; may describe as sharp with direct palpation or during provocative movements

Intensity

Mild to moderate (typically 3-6/10), often worsening with activity and improving with rest

Aggravating

Climbing stairs, running, long walks, knee flexion combined with hip internal rotation, sitting with knees crossed, direct pressure to the bursa

Relieving

Rest, ice application, anti-inflammatory medication, knee extension, hip external rotation stretching

Associated

Swelling over anteromedial knee, warmth in affected area, morning stiffness, pain with resisted hip adduction, possible knee effusion, tightness in hip internal rotators and adductors

Orthopaedic Tests

Pes Anserine Tenderness Test

Procedure

Patient is positioned supine or seated with knee flexed. Palpate directly over the pes anserine insertion on the anteromedial tibia, approximately 2–3 cm below the joint line. Apply gradual pressure and assess for point tenderness.

Positive Finding

Reproduction of local pain or tenderness at the pes anserine insertion site

Sensitivity / Specificity

Unknown / Unknown

Interpretation

Direct palpation tenderness is the primary clinical finding in pes anserine bursitis. While not highly specific, it is a core diagnostic feature. Must be differentiated from medial collateral ligament tenderness (which lies more superiorly) and from medial meniscus pathology.

Noble Compression Test (Modified for Pes Anserine)

Procedure

Patient lies supine. Examiner palpates the pes anserine region while passively flexing and extending the knee, or while applying gentle valgus stress. Pain reproduction with knee movement or stress is assessed.

Positive Finding

Pain with palpation during knee flexion/extension or with mild valgus stress applied to the anteromedial knee

Sensitivity / Specificity

Unknown / Unknown

Interpretation

Reproduction of pain with dynamic movement helps confirm that symptoms originate from the pes anserine rather than static structural pathology. Helps rule out intra-articular pathology.

Resisted Hip Adduction Test

Procedure

Patient is side-lying on the uninvolved side with hip abducted. Examiner provides manual resistance as patient adducts the hip. Alternatively, patient may sit with examiner resisting medial knee-to-midline movement.

Positive Finding

Pain or weakness with resisted hip adduction, particularly in the anteromedial knee region

Sensitivity / Specificity

Unknown / Unknown

Interpretation

Tests the gracilis component of the pes anserine (sartorius, gracilis, semitendinosus). Pain with this test suggests pes anserine involvement given the anatomical attachments and mechanism of overuse injury.

Resisted Knee Flexion Test

Procedure

Patient is seated or prone with knee flexed to 90 degrees. Examiner provides manual resistance as patient attempts to flex the knee further or resists examiner's attempt to extend the knee.

Positive Finding

Pain in the anteromedial tibia region or reproduction of pes anserine tenderness with resisted knee flexion

Sensitivity / Specificity

Unknown / Unknown

Interpretation

Tests the semitendinosus component of the pes anserine. Pain in the pes anserine region (not in the hamstring belly) suggests local bursal or tendon involvement. Helps differentiate from isolated hamstring strain.

Thessaly Test (Modified interpretation for Pes Anserine)

Procedure

Patient stands on one leg with knee slightly flexed (20 degrees) and internally/externally rotates the tibia while the knee flexes and extends slightly. Examiner supports patient for safety and assesses for pain location and character.

Positive Finding

Anteromedial knee pain (rather than joint line pain), localised to the pes anserine region during rotation and dynamic movement

Sensitivity / Specificity

Unknown / Unknown

Interpretation

While primarily a meniscal test, the Thessaly test can provoke pes anserine pain if present. Pain localised anteromediallly away from the joint line suggests pes anserine involvement; joint line pain suggests meniscal pathology.

Ultrasonographic Imaging / Palpation Correlation

Procedure

High-frequency ultrasound (7–12 MHz) imaging of the pes anserine region in transverse and longitudinal planes. Correlate imaging findings with clinical palpation tenderness (sonoelastography or grey-scale thickening of bursa and tendon sheaths).

Positive Finding

Bursal distension (>5 mm thickness), hypoechoic bursal fluid, tendon thickening, or peribursal oedema confirmed on ultrasound and correlated with point of maximal tenderness

Sensitivity / Specificity

88–92% (for bursal distension and inflammation) / See current literature

Interpretation

Ultrasound is the most sensitive imaging modality for detecting bursal inflammation and fluid accumulation. Correlation with palpation-guided imaging improves diagnostic confidence. Helps exclude other medial knee pathology (MCL injury, medial meniscal tear).

⚠ Red Flags

  • Sudden onset following direct trauma with significant swelling and ecchymosis
  • Signs of systemic infection: fever, chills, spreading erythema, regional lymphadenopathy
  • Severe unrelenting pain unresponsive to conservative treatment suggesting alternative diagnosis
  • Locking or catching sensations indicating possible meniscal pathology
  • Significant knee instability or giving way suggesting ligamentous injury
  • Night pain disrupting sleep or pain at rest suggesting inflammatory arthropathy

⚡ Yellow Flags

  • High pain catastrophizing beliefs regarding the injury
  • Fear-avoidance behaviors limiting activity beyond clinical necessity
  • Anxiety about returning to sport or work activities
  • Psychosocial stressors affecting rehabilitation compliance
  • Perceived lack of control over symptoms
  • Previous chronic pain conditions or somatization patterns
  • Poor sleep quality exacerbating inflammation and recovery

Osteopathic Techniques

Region

Hip and pelvis

Technique

MET

Rationale

Muscle energy techniques targeting tight hip adductors, gracilis, and sartorius reduce tension on the pes anserinus tendons and decrease friction on the bursa. Evidence supports MET for improving hip mobility and reducing knee anteromedial pain in athletes.

Region

Hip and pelvis

Technique

Soft Tissue

Rationale

Soft tissue mobilization of hip internal rotators, adductors, and tensor fasciae latae reduces compensatory tension patterns that drive knee valgus and tibial internal rotation. Direct technique reduces muscular guarding and restores normal biomechanics.

Region

Anteromedial knee

Technique

Soft Tissue

Rationale

Gentle soft tissue work around the pes anserinus insertion promotes local circulation, reduces fluid stagnation in the bursa, and decreases pain perception. Avoid direct aggressive pressure over the acutely inflamed bursa.

Region

Tibiofibular and knee joints

Technique

Articulation

Rationale

Gentle knee articulation in pain-free ranges restores synovial fluid distribution, maintains arthrokinematics, and prevents stiffness. Avoids aggravation while maintaining function during acute inflammation.

Region

Hip and knee

Technique

Functional

Rationale

Functional technique addressing the relationship between hip internal/external rotation and knee valgus helps normalize aberrant movement patterns that perpetuate bursal irritation and supports proprioceptive re-education.

Region

Lumbopelvic region

Technique

MET

Rationale

Addressing lumbar and pelvic dysfunction optimizes hip mechanics and reduces compensatory knee valgus. Pelvic stability is prerequisite for normal hip and knee biomechanics in functional activities.

Add-On Approaches

Chinese Medicine

Acupuncture to local points (Ex-LE4, GB34) and distant points (ST36, SP9) to reduce inflammation, promote Qi circulation, and address Liver and Spleen deficiencies contributing to muscular laxity and inflammation

Chiropractic

Knee and hip joint mobilization combined with correction of knee valgus alignment and tibial rotation; proprioceptive neuromuscular facilitation (PNF) patterns to enhance hip abductor control

Physiotherapy

Progressive strengthening of hip abductors (gluteus medius and maximus) through resistance band work and single-leg stance exercises; neuromuscular retraining emphasizing hip control during running and stair climbing

Remedial Massage

Deep tissue massage to hip adductors, gracilis, and sartorius; fascial release techniques to reduce tension in tissues contributing to mechanical irritation of the bursa

Rehabilitation Exercises

Hip Adductor (Gracilis/Adductor Longus) Stretch

StretchingBeginner

Sartorius Stretch (Supine Figure-4 with Flexion)

StretchingBeginner

Hip Internal Rotator Stretch (Figure-4 Piriformis)

StretchingBeginner

Hip Abduction with Resistance Band (Standing)

StrengtheningIntermediate

Gluteus Medius Activation (Clamshells)

StrengtheningBeginner

Single-Leg Stance with Hip Control

StrengtheningIntermediate

Step-Up with Emphasis on Hip Abductor Control

StrengtheningIntermediate

Single-Leg Balance with Dynamic Arm Reach

BalanceIntermediate

Hip Internal and External Rotation (Supine)

Range of MotionBeginner

Hip Abductor Activation During Gait (Walking with Resistance Band)

PosturalIntermediate

Side-Lying Hip Abduction with Knee Extended

StrengtheningIntermediate

Stationary Cycling with Proper Knee Alignment

CardiovascularIntermediate

Referral Criteria

  • Failure to improve after 4-6 weeks of conservative treatment with appropriate activity modification and rehabilitation
  • Clinical signs suggestive of meniscal pathology (locking, catching, positive McMurray test)
  • Evidence of knee ligamentous instability requiring structural imaging or specialist assessment
  • Suspected septic bursitis evidenced by fever, significant local warmth, erythema, and severe pain
  • Persistent swelling and symptoms requiring imaging confirmation or ultrasound-guided aspiration
  • Signs of underlying inflammatory arthropathy (bilateral symptoms, morning stiffness >1 hour, elevated inflammatory markers)
  • Recurrent bursitis suggesting anatomical abnormality or need for advanced imaging (MRI) and specialist management
  • Symptoms suggestive of referred pain from hip (osteoarthritis) or lumbar spine requiring alternative management approach