title: Monitoring of progression of nonsurgically treated rotator cuff tears by magnetic resonance imaging.
abstract: BACKGROUND
  Nonsurgically treated rotator cuff tears sometimes become irreparable in the lead up to surgical repair. The purposes of our study were to identify predictive factors in the progression of tear size, and determine the changes in tear location.
  
  
  METHODS
  Eighty shoulders from 71 patients (mean age 69.4 years) diagnosed with rotator cuff tears by MRI were treated nonsurgically. MRI was repeated after more than 1 year of initial diagnosis. Tear size was measured from the edge of the tear to the lateral aspect of the greater tuberosity. Tears were classified into 5 groups based on tear size and 4 groups based on tear location. Changes in tear size and location were examined.
  
  
  RESULTS
  The mean follow-up period was 22.3 months. The average progression of tear size was 5 mm during follow-up, averaging 3 mm per year. Tears that were initially <1 or ≥4 cm were unlikely to progress in tear size. On the other hand, 1- to 2-cm tears on the initial MRI exhibited the greatest progression in tear size, followed by 2- to 3-cm tears. Furthermore, 62.5 % of localized tears in the posterior of the superior facet spread anteriorly, whereas 88.9 % of localized tears in the anterior of the superior facet did not change.
  
  
  CONCLUSIONS
  Medium-sized tears are at high risk of tear progression. In contrast, there is little risk of early development of irreparable damage in partial tear or small full-thickness tears. In addition, typical tears may start in the posterior of the superior facet, and subsequently spread anteriorly. Our present findings may serve as a useful reference in determining the treatment course for rotator cuff tears.
  
  
  METHODS
  Level IV, Case Series, Prognosis Study.
authors.affiliation: Department of Orthopaedic Surgery, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan, nakamurayoshihiro0419@gmail.com.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Shin
authors.initials: S
authors.lastname: Yokoya
authors.forename: Yu
authors.initials: Y
authors.lastname: Mochizuki
authors.forename: Yohei
authors.initials: Y
authors.lastname: Harada
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Kikugawa
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Ochi
mesh_terms: D000368:Aged; D018450:Disease Progression; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D011379:Prognosis; D017006:Rotator Cuff / Q000473:pathology*; D000070636:Rotator Cuff Injuries; D012421:Rupture / Q000628:therapy