Lower limb
Sacrococcygeal symphysis, obturator membrane, and coccygeal ligaments
Symphysis sacrococcygea, membrana obturatoria et ligamenta coccygea
- Origin
- Apex of sacrum, sacral cornua, and margin of obturator foramen
- Insertion
- Base and cornua of coccyx, and obturator membrane margins
- Function
- Provides flexible attachment for coccyx; closes obturator foramen while providing obturator canal for neurovascular bundle
- Innervation
- Coccygeal nerve and obturator nerve (L2–Co1)
- Movement & chain
- Passive posterior deflection of the coccyx during defecation and parturition
- Palpation
- Palpable in intergluteal cleft at sacrococcygeal junction
- Clinical
- Coccydynia following fall onto buttocks; obturator hernia causing bowel obstruction.
- Segmental innervation
- L2–Co1
- In clinical practice
- Coccyx cushion offloading, pelvic floor therapy, and intrarectal coccygeal mobilization
- Region in the model
- Lower limb