Prevalence of femoroacetabular impingement morphology in asymptomatic youth soccer players: magnetic resonance imaging study with clinical correlation

Abstract

ObjectiveTo determine the prevalence of femoroacetabular impingement morphology (FAIM), cam- or pincer-type, by magnetic resonance imaging (MRI) in asymptomatic adolescent soccer players, and to evaluate the possible correlation between alterations on MRI and clinical examination findings.MethodsA cross-sectional study was conducted to determine the prevalence of FAIM in asymptomatic youth soccer players aged 13–18 years. A total of 112 hips in 56 players (mean age 15.3 years) were evaluated by MRI. Images were examined by two musculoskeletal radiologists for signs of FAIM. Cam-type (impingement) deformity was diagnosed by alpha angle ≥55° or head–neck offset <7 mm. Pincer-type (impingement) deformity was diagnosed by center-edge angle (CEA) ≥35° or acetabular index ≤0°. Other MRI changes, characteristic of FAIM, were observed. Clinical examination was performed to determine the range of motion (ROM) of the hips. In addition, specific tests for anterolateral and posteroinferior impingement were performed.ResultsThe prevalence of MRI findings consistent with FAIM among this young population was 84.8% (95/112). The alpha angle was ≥55° in 77.7% (87/112) of hips, while the CEA was altered in 10.7% (12/112) of hips. Qualitative MRI findings consistent with FAIM were highly prevalent, and included loss of sphericity of the femoral head (77%), osseous bump (44%), femoral neck edema (21%), and acetabular osteitis (9%). The anterior impingement test was positive in 15% of the hips evaluated.ConclusionYouth soccer players have a high prevalence of FAIM as diagnosed by MRI. There is no correlation between physical examination findings and MRI evidence of FAIM in this population.

Pincer‐type MRI morphology seen in over a third of asymptomatic healthy volunteers without femoroacetabular impingement

“…In the last decade the majority of FAI studies have focused on the femur, ie, on the role of the cam‐type deformity in FAI and on the detection of cam‐type deformities on radiographs and MRI . The acetabulum and pincer‐deformities have received less attention, and most studies that assessed pincer‐deformities were based on radiographs, with only little existing MRI data on the morphology of pincer‐deformities, and without an MRI study comparing asymptomatic volunteers directly with FAI patients . This study presents the range of MRI measurements of acetabular morphology in asymptomatic volunteers versus patients with FAI.…”

“…3,20 The acetabulum and pincer-deformities have received less attention, and most studies that assessed pincer-deformities were based on radiographs, [27][28][29][30] with only little existing MRI data on the morphology of pincer-deformities, and without an MRI study comparing asymptomatic volunteers directly with FAI patients. 3,[31][32][33] This study presents the range of MRI measurements of acetabular morphology in asymptomatic volunteers versus patients with FAI. While hip MRI is the standard of reference for assessment of damage to the articular cartilage and labrum, as well as for assessment of cam-type deformities of the proximal femur, 3,31 it can also be applied to quantify the amount of acetabular coverage in patients with suspected pincer and mixed-type FAI.…”

Does a Traumatic Etiology of Hip Pain Influence Hip Arthroscopy Outcomes?

“…A number of studies have indicated that radiographically significant cam and pincer morphology has been identified in anywhere from 5% to 75% of asymptomatic individuals. [7][8][9][10][11] Cam and pincer morphology have been reported to be present at a much greater rate in asymptomatic athletes, with as many as 84.8% of youth soccer players and 95% of collegiate American football players demonstrating radiographically identifiable morphologies associated with hip impingement. 11,12 At this time, it is not known why some patients with hip impingement morphologies have symptoms and others do not; however, traumatic injuries are not the most commonly described pathologic mechanism.…”

“…[7][8][9][10][11] Cam and pincer morphology have been reported to be present at a much greater rate in asymptomatic athletes, with as many as 84.8% of youth soccer players and 95% of collegiate American football players demonstrating radiographically identifiable morphologies associated with hip impingement. 11,12 At this time, it is not known why some patients with hip impingement morphologies have symptoms and others do not; however, traumatic injuries are not the most commonly described pathologic mechanism. Clohisy et al 13 reported on the presenting symptoms of a prospective group of patients undergoing hip arthroscopy for symptomatic FAIS; this study demonstrated that 65% of patients had insidious (atraumatic) onset of symptoms of FAIS and 35% of patients reported a specific traumatic injury.…”

Hip Joint Torsional Loading Before and After Cam Femoroacetabular Impingement Surgery

“…14,24,55 Although previous pathoanatomic studies linked limited hip mobility primarily with the cam deformity, a growing population of athletes have asymptomatic cam morphologic features associated with preadolescent physical activity. 35,38,40,75,84,85…”