Risk factors for ligamentum teres tears

Area of Science:

• Orthopedic surgery
• Radiology
• Hip biomechanics

Background:

• Nontraumatic ligamentum teres (LT) tears are increasingly recognized in hip arthroscopy.
• The association between LT tears and underlying acetabular morphology requires further elucidation.
• Understanding these relationships may inform diagnosis and treatment strategies for hip pain.

Purpose of the Study:

• To investigate the correlation between nontraumatic ligamentum teres (LT) tears and radiographic features of acetabular architecture.
• To determine if specific acetabular parameters are associated with an increased risk of LT tears.
• To explore the role of acetabular coverage, quantified by the Lateral Coverage Index (LCI), in LT tear development.

Main Methods:

• Retrospective analysis of 463 hips undergoing arthroscopic LT examination with anteroposterior pelvis radiographs.
• Exclusion of patients with Tonnis grade 3 arthritis or high-energy trauma.
• Radiographic measurements included acetabular inclination (AI), lateral center edge (CE) angle, cross-over sign, ischial spine prominence, and a calculated Lateral Coverage Index (LCI).

Main Results:

• Of 463 hips, 226 (49%) had LT tears. Patients with tears were older (38 vs. 33 years) and had less acetabular retroversion (lower ischial spine prominence and cross-over sign).
• Hips were categorized by LCI: high (34°+), medium (19°-33°), and low (<19°).
• Low LCI hips were 1.74 times more likely to have LT tears compared to high LCI hips, indicating a link between acetabular undercoverage and LT tears.

Conclusions:

• Nontraumatic LT tears are associated with specific acetabular bony morphology and patient age.
• LT tears were less frequent in hips with high LCI (indicating better coverage) and acetabular retroversion, and in younger patients (<30 years).
• Further research is warranted to establish causality between acetabular undercoverage and LT tears, and to explore if LT tears signify hip microinstability.