title: A comparison of the degree of retraction of full-thickness supraspinatus tears with the Goutallier grading system.
abstract: BACKGROUND
  Tears of the supraspinatus are common and incompletely understood. The degree of fatty infiltration into the muscle is perceived to be a determining factor of successful surgical repair and postoperative function. It is the hypothesis of this study that the degree of central tendon retraction (CTR) as seen on magnetic resonance imaging corresponds to the amount of fatty infiltration classified according to the Goutallier grading system.
  
  
  METHODS
  Magnetic resonance imaging scans of the supraspinatus were reviewed in 2 identifiable groups: 143 scans with no tear (NT) and 148 scans with a full-thickness tear (FTT) and CTR. The degree of CTR and the corresponding Goutallier grade were measured. The difference in Goutallier grade between the NT and FTT groups was measured with the Mann-Whitney test. The relationship between Goutallier grade and increasing amount of CTR was described by use of Spearman rank correlation. Studying the difference between the Goutallier grades and CTR was achieved by use of Mann-Whitney tests.
  
  
  RESULTS
  Of NT scans, 100% showed Goutallier grade 0 or 1. Among FTT scans, 2 showed grade 0, 21 showed grade 1, 35 showed grade 2, 14 showed grade 3, and 76 showed grade 4. The difference was statistically significant (P < .001) between the Goutallier grade 3 and 4 scans, and the degree of Goutallier grade increased with increasing CTR (P < .001).
  
  
  CONCLUSIONS
  Fatty infiltration can be directly linked to CTR and, as such, may help to determine surgical intervention between groups.
authors.affiliation: St Mary's Hospital Paddington, London, UK.
authors.forename: Simon M
authors.initials: SM
authors.lastname: Thompson
authors.forename: Peter
authors.initials: P
authors.lastname: Reilly
authors.forename: Roger J H
authors.initials: RJ
authors.lastname: Emery
authors.forename: Anthony M J
authors.initials: AM
authors.lastname: Bull
mesh_terms: D000273:Adipose Tissue / Q000473:pathology*; D003430:Cross-Sectional Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D017006:Rotator Cuff / Q000473:pathology / Q000601:surgery; D000070636:Rotator Cuff Injuries; D012421:Rupture; D013710:Tendons / Q000473:pathology* / Q000601:surgery