Iliopsoas Tendon: Anatomy, Location, Relations, Function, Clinical Significance, MRI & CT Imaging

Topic

Iliopsoas tendon

The iliopsoas tendon is the distal tendinous portion of the iliopsoas muscle, formed by the union of the psoas major and iliacus muscles. It is one of the strongest tendons crossing the hip joint and plays a major role in flexion of the hip. The tendon passes anterior to the hip joint capsule and inserts into the lesser trochanter of the femur. It is clinically relevant due to its involvement in snapping hip syndrome, iliopsoas tendinopathy, and bursitis.

Synonyms

Tendon of the iliopsoas
Psoas-iliacus tendon
Hip flexor tendon

Location and Course

The tendon is formed by the convergence of the iliacus muscle (from the iliac fossa) and the psoas major muscle (from the lumbar vertebrae)
It courses downward through the pelvis, running anterior to the hip joint capsule
Passes over the iliopectineal eminence and the iliopsoas bursa
Inserts into the lesser trochanter of the femur
A small portion may send slips to the anterior femoral shaft below the trochanter

Relations

Anteriorly: Iliopsoas bursa, femoral nerve, femoral vessels
Posteriorly: Hip joint capsule and femoral head-neck junction
Medially: Pectineus and pubic bone
Laterally: Iliacus muscle fibers

Function

Primary flexor of the hip joint
Assists in external rotation of the thigh
Provides dynamic stabilization of the femoral head within the acetabulum
Plays a critical role in walking, running, and transitions from sitting to standing

Clinical Significance

Iliopsoas tendinitis/tendinopathy: Overuse injury in athletes or runners
Snapping hip syndrome (internal type): Audible or palpable snap due to tendon movement over the iliopectineal eminence or femoral head
Iliopsoas bursitis: Inflammation of the associated iliopsoas bursa, often seen with hip replacement
Post-surgical relevance: Can cause persistent groin pain following total hip arthroplasty due to tendon impingement