title: Factors predicting rotator cuff retears: an analysis of 1000 consecutive rotator cuff repairs.
abstract: BACKGROUND
  The rate of retears after rotator cuff repair varies from 11% to 94%. A retear is associated with poorer subjective and objective clinical outcomes than intact repair.
  
  
  OBJECTIVE
  This study was designed to determine which preoperative and/or intraoperative factors held the greatest association with retears after arthroscopic rotator cuff repair.
  
  
  METHODS
  Cohort study; Level of evidence, 3.
  
  
  METHODS
  This study retrospectively evaluated 1000 consecutive patients who had undergone a primary rotator cuff repair by a single surgeon using an arthroscopic inverted-mattress knotless technique and who had undergone an ultrasound evaluation 6 months after surgery to assess repair integrity. Exclusion criteria included previous rotator cuff repair on the same shoulder, incomplete repair, and repair using a synthetic polytetrafluoroethylene patch. All patients had completed the modified L'Insalata Questionnaire and underwent a clinical examination before surgery. Measurements of tear size, tear thickness, associated shoulder injury, tissue quality, and tendon mobility were recorded intraoperatively.
  
  
  RESULTS
  The overall retear rate at 6 months after surgery was 17%. Retears occurred in 27% of full-thickness tears and 5% of partial-thickness tears (P < .0001). The best independent predictors of retears were anteroposterior tear length (correlation coefficient r = 0.41, P < .0001), tear size area (r = 0.40, P < .0001), mediolateral tear length (r = 0.34, P < .0001), tear thickness (r = 0.29, P < .0001), age at surgery (r = 0.27, P < .0001), and operative time (r = 0.18, P < .0001). These factors produced a predictive model for retears: logit P = (0.039 × age at surgery in years) + (0.027 × tear thickness in %) + (1 × anteroposterior tear length in cm) + (0.76 × mediolateral tear length in cm) - (0.17 × tear size area in cm(2)) + (0.018 × operative time in minutes) -9.7. Logit P can be transformed into P, which is the chance of retears at 6 months after surgery.
  
  
  CONCLUSIONS
  A rotator cuff retear is a multifactorial process with no single preoperative or intraoperative factor being overwhelmingly predictive of it. Nevertheless, rotator cuff tear size (tear dimensions, tear size area, and tear thickness) showed stronger associations with retears at 6 months after surgery than did measures of tissue quality and concomitant shoulder injuries.
authors.affiliation: George A.C. Murrell, MBBS, DPhil, Orthopaedic Research Institute, St George Hospital Campus, University of New South Wales, 4-10 South Street, Level 2, Kogarah, NSW 2217, Australia. murrell.g@ori.org.au.
authors.forename: Brian T N
authors.initials: BT
authors.lastname: Le
authors.forename: Xiao L
authors.initials: XL
authors.lastname: Wu
authors.forename: Patrick H
authors.initials: PH
authors.lastname: Lam
authors.forename: George A C
authors.initials: GA
authors.lastname: Murrell
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001182:Arthroscopy; D056352:Athletes / Q000706:statistics & numerical data; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D061646:Operative Time; D010003:Osteoarthritis / Q000453:epidemiology; D010808:Physical Examination; D012008:Recurrence; D012189:Retrospective Studies; D012399:Rotation; D017006:Rotator Cuff / Q000601:surgery*; D000070636:Rotator Cuff Injuries; D012421:Rupture; D012783:Shoulder Dislocation / Q000453:epidemiology; D053441:Suture Anchors; D055815:Young Adult
keywords: arthroscopic rotator cuff repair; retear; rotator cuff tear; shoulder