Prevalence of Femoroacetabular Impingement Syndrome among Young and Middle-aged White Adults.

Objective: The purpose of the study was to determine the prevalence of femoroacetabular impingement syndrome (FAIS) in white adults 20 to 49 years of age.

Methods: Participants were white men and women aged 20-49 years, recruited through random digit dialing from the population of Metro Vancouver, British Columbia, Canada. Participants filled out a self-administered questionnaire and underwent a physical examination and radiographs of both hips. FAIS was defined as a combination of hip symptoms, physical signs of impingement, and radiological findings of cam or pincer morphology as recommended by the Warwick Agreement. All analyses were weighted to reflect the population from which the sample was drawn.

Results: Data were obtained for 500 participants. In the study population, 48.9% were males and the age distribution was 32.2%, 31.4%, and 36.4% in the groups 20-29, 30-39, and 40-49 years, respectively. The physical signs of impingement correlated significantly with symptoms, but there was no significant association between either symptoms or physical examination with radiographic findings. FAIS on either side was found in 3.0% (95% CI 1.5-4.5) of the population.

Conclusion: In this study, FAIS was present in 3% of whites aged 20-49 years. Further research is needed to develop consistent criteria for assessing hip symptoms, physical signs, and hip joint morphology, and to better understand the relationships between them.