M. obliquus externus abdominis, digitatio costalis VI
The sixth costal digitation of the external abdominal oblique, originating from the lateral surface of the 10th rib.
Origin: Lateral surface of rib 10
Insertion: Linea alba and prepubic tendon via aponeurosis
Action: Flexes the trunk laterally; compresses the abdomen; assists expiration
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 - Costal Digitation VI on our interactive 3D horse model. Open 3D Model