Pelvic Girdle Muscles - Horse Anatomy

The pelvic girdle musculature (sublumbar muscle) is made up of a number of distinct muscle groups. These arise from the lumbar vertebrae and insert on the pelvis or femur. These muscles function in dorsiflexion and ventriflexion of the spine. They also provide stabilisation to the vertebral column and pelvis.

Psoas Minor

Innervation:Intercostal n., Femoral n.

Origin: Last three thoracic vertebrae and 1st-4th lumbar vertebrae

Insertion: ilium

Action: Fixator, flexes lumbar vertebral column

The muscle is marked by multiple tendinous intersections.

Iliac

The iliac muscle is a fleshy muscle that is cross-sectionally flat cranially and round caudally.

Innervation:Lumbar n., Genitofemoral n., Femoral n.

Origin: Two heads, a strong lateral head and small medial head. They enclose the greater psoas and will unite to form a common tendon for insertion.

Medial - ileal shaft

Lateral - Wing of the ilium

Insertion: Lesser trochanter of the femur

Quadrate Lumbar

Thin, tendinous muscle

Innervation: Intercostal n., ventral branches of Lumbar n., Genitofemoral n., Femoral n.

Origin: Proximal end of last rib and transverse process of the cranial lumbar vertebrae

Insertion: Transverse processes of caudal lumbar vertebrae, wing of the sacrum, wing of the ilium

Action: Fixator of lumbar vertebral column