title: Acromial shape in asymptomatic subjects: a study of 305 shoulders in different age groups.
abstract: BACKGROUND
  It has been reported that acromial morphology and age have an independent association with rotator cuff pathology. In a recent study, we found the acromial angle of patients with stage III impingement syndrome (tear in the rotator cuff, according to the Neer classification of shoulder impingement syndrome) to be significantly greater than the acromial angle of their age-matched healthy controls.
  
  
  OBJECTIVE
  To find out if acromial shape also changes, i.e., becomes more curved with age, in shoulders without any rotator cuff problems or previous shoulder surgery.
  
  
  METHODS
  Standard supraspinatus outlet view (SOV) was obtained from both shoulders of healthy persons with no shoulder-related problems or previous shoulder surgery (n = 305; 36 SOVs for subjects aged 21-30 years, 60 for 31-40 years, 67 for 41-50 years, 52 for 51-60 years, 48 for 61-70 years, and 42 for over 71 years of age). Acromial angle, tilt, and the type of the acromion were evaluated.
  
  
  RESULTS
  There were no statistically significant differences in the evaluated morphological parameters between the different age groups.
  
  
  CONCLUSIONS
  Our results suggest that the shape of the acromion does not change with age in individuals who do not have any rotator cuff pathology. According to our results, the changes in acromial morphology seem to be similar in each age group.
authors.affiliation: Department of Orthopedic and Trauma Surgery, Oulu University Hospital, Oulu, Finland.
authors.forename: Matti
authors.initials: M
authors.lastname: Vähäkari
authors.forename: Juhana
authors.initials: J
authors.lastname: Leppilahti
authors.forename: Pekka
authors.initials: P
authors.lastname: Hyvönen
authors.forename: Jukka
authors.initials: J
authors.lastname: Ristiniemi
authors.forename: Markku
authors.initials: M
authors.lastname: Päivänsalo
authors.forename: Pekka
authors.initials: P
authors.lastname: Jalovaara
mesh_terms: D000174:Acromion / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D000328:Adult; D000367:Age Factors; D000368:Aged; D016009:Chi-Square Distribution; D006801:Humans; D008875:Middle Aged; D011859:Radiography; D012016:Reference Values