The transverse acetabular ligament, though small in size, plays a unique role in the anatomy and function of the hip joint. It completes the circular rim of the acetabulum and provides attachment points for other structures.
Location
This ligament spans the acetabular notch, an indentation located at the inferior aspect of the acetabulum, which is the concave surface of the pelvis where the head of the femur articulates.
Structure
- Morphology: The transverse acetabular ligament is a strong, crescent-shaped band of fibers that bridges the acetabular notch, converting this notch into a foramen.
- Composition: Like most ligaments, it is made up of dense connective tissue with intertwined fibrous structures, providing it with the necessary strength.
Function
- Completion of the Acetabulum: One of its primary roles is to complete the circular boundary of the acetabulum, thereby ensuring a deeper socket for the femoral head, which enhances joint stability.
- Attachment Site: This ligament serves as an attachment point for the ligamentum teres, a ligament that connects the femoral head to the acetabulum.
- Vascular Passage: The foramen it creates allows for the passage of the acetabular branch of the obturator artery, which contributes to the blood supply of the hip joint.
Clinical significance
The transverse acetabular ligament’s clinical significance, while subtle, is notable in various aspects of hip anatomy and function. Serving as the anatomical bridge for the acetabular notch, it completes the acetabulum’s rim, thereby ensuring a deeper and more secure articulation for the femoral head, which aids in preventing potential subluxations or dislocations. Its role as an attachment site for the ligamentum teres is crucial; any compromise to the ligament can indirectly affect the stability and function of the ligamentum teres.
Additionally, the ligament’s provision of passage for the acetabular branch of the obturator artery means that any trauma or surgical intervention in the region must carefully consider this vascular structure to avoid complications. In hip surgeries, including total hip arthroplasty, the integrity of this ligament, and its relationship with surrounding structures, can influence surgical decisions and outcomes. Furthermore, in radiological evaluations, the ligament can serve as a landmark, aiding in the assessment of acetabular depth and potential abnormalities.
