Acetabular Rim Ossification Variants Are Found in Almost 20% of Patients Presenting With Hip Pain

Area of Science:

• Orthopaedic surgery
• Radiology
• Hip imaging

Background:

• Periacetabular calcifications are varied and their prevalence is not well-established.
• Understanding these ossifications is crucial for diagnosing hip conditions.

Purpose of the Study:

• To determine the prevalence of four types of acetabular rim ossifications.
• To identify demographic and radiological factors associated with these ossifications.

Main Methods:

• Retrospective review of 982 hip radiographs from 491 patients with hip complaints.
• Analysis of cam/pincer femoroacetabular impingement, Tönnis grade, and periacetabular calcifications.
• Evaluation of associations with sex, age, and radiological parameters.

Main Results:

• Overall prevalence of periacetabular calcifications was 17.6%.
• Four patterns identified: punctate labral calcifications (8%), os acetabuli (4.2%), acetabular rim stress fractures (2%), and complete labral ossification (3.4%).
• Male sex, increased lateral center-edge angle, and higher Tönnis grade predicted ossification. Specific factors linked to each pattern.

Conclusions:

• Periacetabular calcifications are common, with distinct patterns and prevalence rates.
• Demographic and radiological factors are associated with different types of ossifications.
• This study provides a framework for categorizing and understanding these hip conditions.