1839. Acetabular Labrum Ossification: Prevalence in Asymptomatic Non-Osteoarthritic Hips and Relation to Patient and Hip Characteristics
Authors * Denotes Presenting Author
  1. Catarina Valente *; Lausanne University Hospital
  2. Laura Haefliger; Lausanne University Hospital
  3. Julien Favre; Lausanne University Hospital
  4. Patrick Omoumi; Lausanne University Hospital
To estimate the prevalence of acetabular ossifications in the adult population with asymptomatic, morphologically normal hips at CT and to determine whether the presence of labral ossifications is associated with patient-related (sex, age, BMI), or hip-related parameters (joint space width, and cam- and pincer-type femoroacetabular impingement morphotype).

Materials and Methods:
We prospectively included all patients undergoing thoracoabdominal CT over a 3-month period. After exclusion of patients with a clinical history of hip pathology and/or with signs of osteoarthritis on CT, we included a total of 150 hips from 75 patients. We analyzed the presence and the size of labral ossifications around the acetabular rim. The relationships between the size of labral ossifications and patient- and hip-related parameters were tested using multiple regression analysis.

The prevalence of labral ossifications in this population of asymptomatic, non-OA hips was 96% (95%CI=[80.1; 100.0]). The presence of labral ossifications and their size were correlated between right and left hips (Spearman coefficient=0.64 (95%CI=[0.46; 0.79]), p<0.05)).The size of labral ossifications was significantly associated with age (p<0.0001) but not with BMI (p=0.35), gender (p=0.05), joint space width (p >= 0.53 for all locations) or any of the qualitative or quantitative parameters associated with femoroacetabular morphotype (all p >= 0.34).

Labral ossifications are extremely common in asymptomatic, non-osteoarthritic hips. Their size is not correlated with any patient-, or hip-related parameters except for the age. These findings suggest that the diagnosis of osteoarthritis or femoroacetabular impingement morphotype should not be made based on the sole presence of acetabular labral ossifications.