title: Developmental pattern of the hip in patients with hereditary multiple exostoses.
abstract: BACKGROUND
  Coxa valga is a common clinical feature of hereditary multiple exostoses (HME). The current study aimed to determine the unique developmental pattern of the hip in patients with HME and evaluate the factors that influence its progression.
  
  
  METHODS
  Thirty patients (57 hips) with HME were divided into two groups according to the Hilgenreiner epiphyseal angle (HEA). Twenty-two patients (44 hips) including 13 men and 9 women were assigned to group 1 (HEA <25°), and 8 patients (13 hips) including 3 men and 5 women were assigned to group 2 (HEA ≥25°). The mean age at the initial presentation was 6.0 (4-12) years with 6.8 (4-11) years of follow-up in group 1, and 10.4 (8-13) years with 5.4 (2-9) years of follow-up in group 2. We measured the HEA, neck-shaft angle (NSA), acetabular index (AI), center-edge angle (CEA), and migration percentage (MP) for radiographic evaluation.
  
  
  RESULTS
  Among the hips, 50 (87.7%) hips had coxa valga and 27 (47.4%) hips had abnormal MP (42.1% were borderline and 5.3% were subluxated). There was a significant difference in the HEA and NSA between the groups (p < 0.001 and p < 0.05, respectively). The HEA significantly correlated with the development of the NSA and no correlation was found between the HEA and AI, CEA, and MP.
  
  
  CONCLUSIONS
  There was a significant relationship between the HEA at the initial presentation and the NSA at skeletal maturity. We should consider guided growth for patients with lower HEA to prevent significant coxa valga deformity with close follow-up.
authors.affiliation: Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, Xuhui District, Shanghai, China. wyzthebest@hotmail.com.
authors.forename: Ya-Zhou
authors.initials: YZ
authors.lastname: Wang
authors.affiliation: Institute for Rare Diseases Department of Orthopaedic Surgery, Korea University Medical College, 148 Gurodong-ro, Guro-gu, Seoul, 152-703, Korea. kwpark77@gmail.com.
authors.forename: Kwang-Won
authors.initials: KW
authors.lastname: Park
authors.affiliation: Department of Orthopaedic Surgery, Chonnam National University Hospital, Hak Dong 8, Gwangju, 500-757, Korea. joni43@hanmail.net.
authors.forename: Chang-Seon
authors.initials: CS
authors.lastname: Oh
authors.affiliation: Department of Orthopaedic Surgery, Chonnam National University Hospital, Hak Dong 8, Gwangju, 500-757, Korea. ssubian@naver.com.
authors.forename: Yeong-Seub
authors.initials: YS
authors.lastname: Ahn
authors.affiliation: Department of Orthopedic Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, Xuhui District, Shanghai, China. kangqinglin@hotmail.com.
authors.forename: Qing-Lin
authors.initials: QL
authors.lastname: Kang
authors.affiliation: Department of Orthopaedic Surgery, Chonnam National University Hospital, Hak Dong 8, Gwangju, 500-757, Korea. stjung@jnu.ac.kr.
authors.forename: Sung-Taek
authors.initials: ST
authors.lastname: Jung
authors.affiliation: Institute for Rare Diseases Department of Orthopaedic Surgery, Korea University Medical College, 148 Gurodong-ro, Guro-gu, Seoul, 152-703, Korea. songhae@korea.ac.kr.
authors.forename: Hae-Ryong
authors.initials: HR
authors.lastname: Song
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging / Q000254:growth & development; D000293:Adolescent; D001696:Biomechanical Phenomena; D002648:Child; D002675:Child, Preschool; D060906:Coxa Valga / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D018450:Disease Progression; D004838:Epiphyses / Q000000981:diagnostic imaging / Q000254:growth & development; D005097:Exostoses, Multiple Hereditary / Q000150:complications* / Q000000981:diagnostic imaging / Q000503:physiopathology; D005260:Female; D005272:Femur Neck / Q000000981:diagnostic imaging / Q000254:growth & development; D005500:Follow-Up Studies; D006618:Hip Dislocation, Congenital / Q000000981:diagnostic imaging / Q000209:etiology* / Q000503:physiopathology; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000254:growth & development*; D006801:Humans; D008297:Male; D011859:Radiography; D016059:Range of Motion, Articular; D013997:Time Factors; D055815:Young Adult