Prevalence of cam-type deformities of the hip in asymptomatic adults

OBJECTIVES: The prevalence of asymptomatic femoroacetabular impingement (FAI) is unknown in the general population. The purpose of this study is to determine the prevalence of cam-type deformities in asymptomatic persons. METHODS: We evaluated 84 volunteers without symptoms of FAI, which underwent a lateral radiograph of both hips. To determine the presence of cam type deformities, α-angle measurement was used. An α-angle > 50 ° indicates the presence of cam type deformity. RESULTS: The average age was 28.7 years, with 18 females and 66 males. Of the 84 volunteers, 16 (19%) had an α-angle> 50 °, while the remaining 68 patients had α-angle <50 °. We found the presence of a cam- type deformity in 22.7% of males and 5.5% of women. CONCLUSION: Our results are consistent with the literature reviewed, finding a prevalence of 13.9 to 24.7% in men and in women 4-5.5% according to different authors. The high frequency of cam-type deformities in asymptomatic patients suggests that a high α-angle itself not only ensures the presence of symptoms or progression to osteoarthritis. Therefore, we hold that this finding should be complemented by physical examination, clinical symptoms and other imaging signs when taking decisions regarding the therapeutic management.