Obturator Internus

Introduction

Illustration of Obturator Internus

Illustration of Triceps Coxae

Other Names

• Obturator Internus
• Obturator Internus Muscle
• Musculus Obturator Internus

Description

• Bilateral triangular-shaped muscle situated deep within both the pelvic and gluteal regions

Origin

• Posterior surface of the obturator membrane
• Obturator foramen

Insertion

• Femur, specifically medial surface of greater trochanter of femur

Triceps Coxae

• So called for sharing a common insertion on the greater trochanter of the femur
• Obturator Internus, Superior Gemellus, Inferior Gemellus

Bursa of Obturator Internus

• Typically found between the tendon and the ischium
• Allows for free movement of the tendon over the bone without friction
• A second, long narrow bursa is often interposed between the common tendon and joint capsule
  • Sometimes communicated with bursa of obturator internus

Actions

• External Rotation and Abduction of thigh
• Stabilizes hip joint

Vascular Supply

• Obturator Artery
• Internal Pudendal Artery

Innervation

• Obturator Internus Nerve (L5-S1)

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Clinical Significance

• Obturator Internus Injection
• Obturator Internus Pain

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See Also

• Physical Exam Hip
• Hip Anatomy Main
• Hip Pain Main
• Bursae Anatomy Main

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