title: Development of secondary ossification centres of the acromion in Japanese youth: a computed tomographic study.
abstract: OBJECTIVE
  To determine the age range when the secondary ossification centres of the acromion appear and fuse in Japanese youth using computed tomography (CT).
  
  
  METHODS
  CT scans of 85 shoulders in 35 male and 14 female consecutive patients aged 6 to 20 (mean, 16) years were reviewed. No patient had pain or tenderness at the acromion. Appearance and fusion of the secondary ossification centres of the acromion were determined twice by an orthopaedist. A secondary ossification centre was considered to have appeared when a low-density line was noted at the juxta-epiphyseal area and to have fused when the line had disappeared. Intra-observer reliability was determined.
  
  
  RESULTS
  The intra-observer reliability was 0.93. The secondary ossification centres of the acromion had appeared at around 10 years of age and had fused at around 15 years of age, with one exception.
  
  
  CONCLUSIONS
  In these Japanese subjects, the secondary ossification centres of the acromion had appeared at around 10 years of age and had fused at 15 to 16 years.
authors: Tokushima Red Cross Hospital, Japan.
authors: Koji
authors: K
authors: Fujii
authors: Yoshitsugu
authors: Y
authors: Takeda
authors: Katsutoshi
authors: K
authors: Miyatake
mesh_terms: D000174:Acromion / Q000000981:diagnostic imaging*; D000293:Adolescent; D000375:Aging / Q000502:physiology*; D002648:Child; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D010012:Osteogenesis / Q000502:physiology*; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed / Q000379:methods*; D055815:Young Adult
keywords: acromion; bone development; tomography, X-ray computed