Cervical Ridge of the Acetabulum: Anatomy, Biomechanics, and Surgical Relevance

The cervical ridge (also called the acetabular cervical ridge or superior acetabular ridge) is a bony prominence on the superior-anterior aspect of the acetabular rim, formed by the junction of the acetabular labrum and the subchondral bone of the femoral head contact zone.

Anatomical Description

• Location: Anterior-superior acetabular margin, contiguous with the anterior inferior iliac spine (AIIS) region.
• Structure: Dense subchondral bone covered by labral fibrocartilage.
• Function: Acts as a buttress that supports the femoral head during hip flexion, preventing anterior subluxation.

Biomechanical Role

• In flexion + external rotation, the femoral head translates anteriorly; the cervical ridge engages the femoral neck/head junction, limiting excessive translation.
• Deficiency or removal (e.g., during aggressive rim trimming in FAI surgery) can increase risk of iatrogenic instability or anterior microinstability.

Clinical Significance

Trauma (Anterior Wall Fracture)

Context	Relevance
Femoroacetabular Impingement (FAI) — Pincer type	Prominent cervical ridge = focal overcoverage → labral shear, chondral damage.
Hip Arthroscopy (Rim Trimming)	Preserve cervical ridge to maintain anterior stability; resect only pathological overcoverage.
Periacetabular Osteotomy (PAO)	Cervical ridge orientation guides reorientation; must maintain anterior coverage.
Total Hip Arthroplasty	Acetabular component positioning must respect cervical ridge anatomy for stability.
Cervical ridge fracture = anterior column injury; may require ORIF.

Imaging Identification

• AP Pelvis: "Cross-over sign" (posterior wall line crosses anterior wall line) suggests global overcoverage; cervical ridge prominence seen as sharp anterior rim density.
• False Profile / Dunn View: Profiles anterior acetabular wall and cervical ridge.
• CT 3D / MRI: Definitive morphology; labral pathology at ridge.

The cervical ridge is a critical stabilizer of the hip in flexion—preserve it during joint-preserving surgery.