title: Characteristic retear patterns assessed by magnetic resonance imaging after arthroscopic double-row rotator cuff repair.
abstract: OBJECTIVE
  The purpose of this study was to examine magnetic resonance imaging (MRI) findings and elucidate retear pattern and its characteristics after surgical repair of the rotator cuff using an arthroscopic double-row suture anchor (DRSA) method.
  
  
  METHODS
  Forty-seven patients with complete rotator cuff tears treated by the DRSA method under arthroscopy whose repair condition was assessed by MRI approximately 12 months after the procedure were included in the study. The mean age at treatment was 65 years (range, 42 to 82 years). The mean follow-up period was 26 months (range, 24 to 32 months).
  
  
  RESULTS
  The repair integrity was classified into 5 groups according to MRI findings. A well-repaired tendon was seen in 34 shoulders. Partial retearing of the deep layer was observed in 2. Partial retearing of the superficial layer around the medial anchors was observed in 3. Complete retearing of the tendon around the medial anchors with a well-preserved footprint was observed in 4. Complete retearing of the tendon from the footprint was observed in 4. The retear patterns involving superficial retearing and complete retearing around the medial anchors were unexpected and unique. These types of retears seem to be characteristic of the DRSA method and were seen in cases with medium-sized tears. The incidence of characteristic retearing was 7 of 47.
  
  
  CONCLUSIONS
  Superficial-side partial tearing and complete tearing around the medial-row anchors with a well-repaired tendon on the footprint could be characteristics of the DRSA method. These retear patterns were observed in 7 of 13 retear cases and 7 of 47 cases overall. The retear rate by the characteristic retear was high. Exploring the causes of this retear and preventing it could lead to better clinical results with the DRSA method.
  
  
  METHODS
  Level IV, therapeutic case series.
authors.affiliation: Department of Orthopedic Surgery, Osaka Police Hospital, Osaka, Japan. hkenji@leto.eonet.ne.jp
authors.forename: Kenji
authors.initials: K
authors.lastname: Hayashida
authors.forename: Makoto
authors.initials: M
authors.lastname: Tanaka
authors.forename: Kota
authors.initials: K
authors.lastname: Koizumi
authors.forename: Masaaki
authors.initials: M
authors.lastname: Kakiuchi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001182:Arthroscopy / Q000295:instrumentation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D020127:Recovery of Function; D012008:Recurrence; D017006:Rotator Cuff / Q000473:pathology / Q000601:surgery; D000070636:Rotator Cuff Injuries; D053441:Suture Anchors; D013708:Tendon Injuries / Q000473:pathology / Q000601:surgery*; D016896:Treatment Outcome