Sacrotuberous ligament

Dr Henry Knipe et al.

The sacrotuberous ligament (STL) is a stabiliser of the sacro-iliac joint and connects the bony pelvis to the vertebral column

Gross anatomy

The STL has a broad fan-like origin from the sacrum, coccyx, ilium and sacro-iliac joint capsule. Its fibres converge to course caudally to insert into the medial ischial tuberosity and additional fibres (known as the falciform ligament) extend to the ischial ramus 1, 3

It forms a boundary of the greater and lesser sciatic foramen. Many of its fibres blend with other musculotendinous structures 1, 3:

The sacrotuberous ligament is pierced by coccygeal branches of the inferior gluteal artery, the perforating cutaneous nerve and branches of the coccygeal plexus 3

Related pathology


Abdominal and pelvic anatomy
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Article Information

rID: 29754
Section: Anatomy
Tag: pelvis
Synonyms or Alternate Spellings:
  • Sacrotuberous ligament (STL)

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Cases and Figures

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    Figure 1
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    Case 1: sacrotuberous ligament calcification in AS
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    Case 2: sacrotuberous ligament ossification
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