TY - JOUR
T1 - Radiographic Prevalence of Dysplasia, Cam, and Pincer Deformities in Elite Ballet
AU - Harris, Joshua D.
AU - Gerrie, Brayden J.
AU - Varner, Kevin E.
AU - Lintner, David M.
AU - McCulloch, Patrick C.
N1 - Publisher Copyright:
© 2015 The Author(s.
Copyright:
Copyright 2016 Elsevier B.V., All rights reserved.
PY - 2016/1/1
Y1 - 2016/1/1
N2 - Background: The demands of hip strength and motion in ballet are high. Hip disorders, such as cam and pincer deformities or dysplasia, may affect dance performance. However, the prevalence of these radiographic findings is unknown. Purpose: To determine the prevalence of radiographic cam and pincer deformities, borderline dysplasia, and dysplasia in a professional ballet company. Study Design: Cross-sectional study; Level of evidence, 3. Methods: An institutional review board-approved cross-sectional investigation of a professional ballet company was undertaken. Male and female adult dancers were eligible for inclusion. Four plain radiographs were obtained (standing anteroposterior pelvis, bilateral false profile, and supine Dunn 45°) and verified for adequacy. Cam and pincer deformities, dysplasia, borderline dysplasia, and osteoarthritis were defined. All plain radiographic parameters were measured and analyzed on available radiographs. Student t test, chi-square test (and Fisher exact test), and Spearman correlation analyses were performed to compare sexes, groups, and the effect of select radiographic criteria. Results: A total of 47 dancers were analyzed (21 males, 26 females; mean age (±SD), 23.8 ± 5.4 years). Cam deformity was identified in 25.5% (24/94) of hips and 31.9% (15/47) of subjects, with a significantly greater prevalence in male dancers than females (48% hips and 57% subjects vs 8% hips and 12% subjects; P <.001 and P =.001, respectively). Seventy-four percent of subjects had at least 2 of 6 radiographic signs of pincer deformity. Male dancers had a significantly greater prevalence of both prominent ischial spine and posterior wall signs (P =.001 and P <.001, respectively), while female dancers had a significantly greater prevalence of coxa profunda (85% female hips vs 26% male hips; P <.001). Eighty-nine percent of subjects had dysplasia or borderline dysplasia in at least 1 hip (37% dysplastic), with a significantly greater prevalence of dysplasia or borderline dysplasia in female versus male dancers (92% female hips vs 74% male hips; P <.022). Further, in those with dysplasia or borderline dysplasia, 92% of female and 82% of male dancers had bilateral findings. Conclusion: In this professional ballet company, a high prevalence of radiographic abnormalities was found, including cam and pincer deformity and dysplasia. The results also revealed several sex-related differences of these abnormalities in this unique population. The long-term implications of these findings in this group of elite athletes remain unknown, and this issue warrants future investigation.
AB - Background: The demands of hip strength and motion in ballet are high. Hip disorders, such as cam and pincer deformities or dysplasia, may affect dance performance. However, the prevalence of these radiographic findings is unknown. Purpose: To determine the prevalence of radiographic cam and pincer deformities, borderline dysplasia, and dysplasia in a professional ballet company. Study Design: Cross-sectional study; Level of evidence, 3. Methods: An institutional review board-approved cross-sectional investigation of a professional ballet company was undertaken. Male and female adult dancers were eligible for inclusion. Four plain radiographs were obtained (standing anteroposterior pelvis, bilateral false profile, and supine Dunn 45°) and verified for adequacy. Cam and pincer deformities, dysplasia, borderline dysplasia, and osteoarthritis were defined. All plain radiographic parameters were measured and analyzed on available radiographs. Student t test, chi-square test (and Fisher exact test), and Spearman correlation analyses were performed to compare sexes, groups, and the effect of select radiographic criteria. Results: A total of 47 dancers were analyzed (21 males, 26 females; mean age (±SD), 23.8 ± 5.4 years). Cam deformity was identified in 25.5% (24/94) of hips and 31.9% (15/47) of subjects, with a significantly greater prevalence in male dancers than females (48% hips and 57% subjects vs 8% hips and 12% subjects; P <.001 and P =.001, respectively). Seventy-four percent of subjects had at least 2 of 6 radiographic signs of pincer deformity. Male dancers had a significantly greater prevalence of both prominent ischial spine and posterior wall signs (P =.001 and P <.001, respectively), while female dancers had a significantly greater prevalence of coxa profunda (85% female hips vs 26% male hips; P <.001). Eighty-nine percent of subjects had dysplasia or borderline dysplasia in at least 1 hip (37% dysplastic), with a significantly greater prevalence of dysplasia or borderline dysplasia in female versus male dancers (92% female hips vs 74% male hips; P <.022). Further, in those with dysplasia or borderline dysplasia, 92% of female and 82% of male dancers had bilateral findings. Conclusion: In this professional ballet company, a high prevalence of radiographic abnormalities was found, including cam and pincer deformity and dysplasia. The results also revealed several sex-related differences of these abnormalities in this unique population. The long-term implications of these findings in this group of elite athletes remain unknown, and this issue warrants future investigation.
KW - ballet
KW - dance
KW - dysplasia
KW - femoroacetabular impingement
KW - hip
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U2 - 10.1177/0363546515601996
DO - 10.1177/0363546515601996
M3 - Article
C2 - 26324404
AN - SCOPUS:84953238239
SN - 0363-5465
VL - 44
SP - 20
EP - 27
JO - American Journal of Sports Medicine
JF - American Journal of Sports Medicine
IS - 1
ER -