title: Radiographic Hip Anatomy Correlates With Range of Motion and Symptoms in National Hockey League Players.
abstract: BACKGROUND
  Hip disorders in athletes have been increasingly recognized.
  
  
  OBJECTIVE
  To characterize radiographic hip anatomy for National Hockey League (NHL) players and correlate it with hip range of motion and hip symptoms and/or surgery.
  
  
  METHODS
  Cross-sectional study; Level of evidence, 3.
  
  
  METHODS
  Fifty-nine professional hockey players (118 hips) with 1 NHL organization (mean age, 24.2 years; range, 18-36) prospectively underwent history and physician examination by 2 independent orthopaedic surgeons. Current or previous groin and/or hip pain or surgery was noted. Anteroposterior (AP) pelvis and bilateral Dunn lateral radiographs were obtained for all players with assessment of hip morphology by 2 blinded independent orthopaedic surgeons.
  
  
  RESULTS
  Good to very good reliability of radiographic assessments was noted (intraclass correlation coefficients = 0.749-0.958). Sixty-four percent of athletes had a positive crossover sign, while 86% and 60% had a positive posterior wall sign and a prominent ischial spine sign, respectively. Twenty-one percent of hips demonstrated dysplastic acetabular features (lateral center edge angle <25°). Eighty-five percent and 89% of hips demonstrated cam-type morphology based on alpha angle (>50° Dunn lateral) and head-neck offset, respectively. Good to very good reliability was noted for ROM assessments (intraclass correlation coefficient >0.69). Mean hip flexion was 107.4º ± 6.7º, and mean hip internal rotation was 26.1º ± 6.6º. Thirty-one percent of hips had a history of hip-related pain and/or surgery. Higher AP, Dunn lateral, and maximal alpha angles correlated with decreased hip internal rotation ( P = .004). Greater AP alpha angle correlated with decreased hip extension/abduction ( P = .025), and greater Dunn lateral and maximal alpha angle correlated with decreased hip flexion/abduction ( P = .001). A positive posterior wall sign correlated with increased straight hip abduction, while other radiographic acetabular parameters were not predictive of range of motion. Only decreased hip external rotation and total arc of motion correlated with an increased risk for current or prior hip symptoms or surgery ( P < .001).
  
  
  CONCLUSIONS
  Hip anatomy in NHL players is characterized by highly prevalent cam-type morphology (>85%) and acetabular retroversion (>60%). In addition, acetabular dysplasia (21%) was relatively common. Greater cam-type morphology correlated with decreased hip range of motion, and a positive crossover sign correlated with increased hip abduction. Decreased hip external rotation and total arc of motion were predictive of hip-related pain and/or surgery.
authors.affiliation: Minnesota Orthopedic Sports Medicine Institute, Twin Cities Orthopedics, Edina, Minnesota, USA.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Larson
authors.affiliation: Boca Care Orthopedics, Boca Raton Regional Hospital, Boca Raton, Florida, USA.|College of Medicine, Florida Atlantic University, Boca Raton, Florida, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Ross
authors.affiliation: Department of Orthopaedic Surgery-MedSport, University of Michigan Medical School, Ann Arbor, Michigan, USA.
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Kuhn
authors.affiliation: Minnesota Wild Hockey Club, National Hockey League, St Paul, Minnesota, USA.
authors.forename: Donnie
authors.initials: D
authors.lastname: Fuller
authors.affiliation: Fairview/MOSMI Orthopedic Fellowship Program, Minneapolis, Minnesota, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Rowley
authors.affiliation: Minnesota Orthopedic Sports Medicine Institute, Twin Cities Orthopedics, Edina, Minnesota, USA.
authors.forename: M Russell
authors.initials: MR
authors.lastname: Giveans
authors.affiliation: Minnesota Orthopedic Sports Medicine Institute, Twin Cities Orthopedics, Edina, Minnesota, USA.
authors.forename: Rebecca M
authors.initials: RM
authors.lastname: Stone
authors.affiliation: Department of Orthopaedic Surgery-MedSport, University of Michigan Medical School, Ann Arbor, Michigan, USA.
authors.forename: Asheesh
authors.initials: A
authors.lastname: Bedi
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging; D018771:Arthralgia / Q000209:etiology; D003430:Cross-Sectional Studies; D006119:Groin; D025981:Hip Injuries / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology*; D006621:Hip Joint / Q000000981:diagnostic imaging* / Q000473:pathology / Q000502:physiology* / Q000503:physiopathology; D006688:Hockey / Q000293:injuries*; D006801:Humans; D008297:Male; D010146:Pain / Q000209:etiology; D015995:Prevalence; D011859:Radiography; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D012399:Rotation; D055815:Young Adult
keywords: adductor; anatomy; femoroacetabular impingement; groin; hip; ice hockey; radiographs; range of motion; symptoms