title: Repair integrity and functional outcome after arthroscopic double-row rotator cuff repair. A prospective outcome study.
abstract: BACKGROUND
  The retear rate following rotator cuff repair is variable. Recent biomechanical studies have demonstrated that double-row tendon-to-bone fixation excels in initial fixation strength and footprint coverage compared with the single-row or transosseous fixation methods. This study was designed to report the repair integrity and clinical outcome following arthroscopic double-row rotator cuff repair.
  
  
  METHODS
  A consecutive series of 106 patients with full-thickness rotator cuff tears underwent arthroscopic double-row rotator cuff repair with use of suture anchors and were followed prospectively. Twenty patients lacked complete follow-up data or were lost to follow-up. The eighty-six study subjects included fifty-two men and thirty-four women, with an average age of 60.5 years. There were twenty-six small, thirty medium, twenty-two large, and eight massive tears. Clinical outcomes were evaluated at an average of thirty-one months. Repair integrity was estimated with use of magnetic resonance imaging, which was performed, on the average, fourteen months postoperatively, and was classified into five categories, with type I indicating sufficient thickness with homogeneously low intensity; type II, sufficient thickness with partial high intensity; type III, insufficient thickness without discontinuity; type IV, the presence of a minor discontinuity; and type V, the presence of a major discontinuity.
  
  
  RESULTS
  The average clinical outcome scores all improved significantly at the time of the final follow-up (p < 0.01). At a mean of fourteen months postoperatively, magnetic resonance imaging revealed that thirty-seven shoulders had a type-I repair; twenty-one, a type-II repair; thirteen, a type-III repair; eight, a type-IV repair; and seven, a type-V repair. The overall rate of retears (types IV and V) was 17%. The retear rate was 5% for small-to-medium tears, while it was 40% for large and massive tears. The shoulders with a type-V repair demonstrated significantly inferior functional outcome in terms of overall scores and strength compared with the other types of repairs (p < 0.01).
  
  
  CONCLUSIONS
  Arthroscopic double-row repair can result in improved repair integrity compared with open or miniopen repair methods. However, the retear rate for shoulders with large and massive tears remains higher than that for smaller tears, and shoulders with large repair defects (type V) demonstrate significantly inferior functional outcomes.
authors.affiliation: Funabashi Orthopaedic Sports Medicine Center, 1-833 Hazama, Funabashi, Chiba 2740822, Japan. hsugaya@nifty.com
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Sugaya
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Maeda
authors.forename: Keisuke
authors.initials: K
authors.lastname: Matsuki
authors.forename: Joji
authors.initials: J
authors.lastname: Moriishi
mesh_terms: D000328:Adult; D000368:Aged; D001182:Arthroscopy / Q000379:methods*; D002985:Clinical Protocols; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D020127:Recovery of Function; D012008:Recurrence; D000070636:Rotator Cuff Injuries; D012421:Rupture; D016896:Treatment Outcome