M. obliquus externus abdominis, crus laterale
The lateral crus of the superficial inguinal ring, formed by the aponeurosis of the external abdominal oblique. This tendinous band forms the lateral boundary of the superficial inguinal ring and is a critical landmark in inguinal hernia surgery and castration.
Origin: Aponeurosis of external abdominal oblique
Insertion: Iliac fascia; tuber coxae
Action: Forms lateral boundary of superficial inguinal ring; supports inguinal region
Innervation: Ventral branches of thoracic (T10–T18) and lumbar (L1–L3) spinal nerves
Strain or tearing of individual costal digitations of the external abdominal oblique, often from trauma (kicks) or sudden rotational movements. Common site for abdominal wall herniation in horses.
Strain or tearing of individual costal digitations of the external abdominal oblique, often from trauma (kicks) or sudden rotational movements. Common site for abdominal wall herniation in horses. Signs include: Localized swelling over the affected rib; pain on palpation; reluctance to bend laterally; may develop into a hernia if multiple digitations are disrupted.
See the External Abdominal Oblique - Pelvic Tendon (Crus Laterale) on our interactive 3D horse model. Open 3D Model