title: Cyclic loading of rotator cuff reconstructions: single-row repair with modified suture configurations versus double-row repair.
abstract: BACKGROUND
  Double-row repair is suggested to have superior biomechanical properties in rotator cuff reconstruction compared with single-row repair. However, double-row rotator cuff repair is frequently compared with simple suture repair and not with modified suture configurations.
  
  
  OBJECTIVE
  Single-row rotator cuff repairs with modified suture configurations have similar failure loads and gap formations as double-row reconstructions.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  We created 1 x 2-cm defects in 48 porcine infraspinatus tendons. Reconstructions were then performed with 4 single-row repairs and 2 double-row repairs. The single-row repairs included transosseous simple sutures; double-loaded corkscrew anchors in either a double mattress or modified Mason-Allen suture repair; and the Magnum Knotless Fixation Implant with an inclined mattress. Double-row repairs were either with Bio-Corkscrew FT using modified Mason-Allen stitches or a combination of Bio-Corkscrew FT and PushLock anchors using the SutureBridge Technique. During cyclic load (10 N to 60-200 N), gap formation was measured, and finally, ultimate load to failure and type of failure were recorded.
  
  
  RESULTS
  Double-row double-corkscrew anchor fixation had the highest ultimate tensile strength (398 +/- 98 N) compared to simple sutures (105 +/- 21 N; P < .0001), single-row corkscrews using a modified Mason-Allen stitch (256 +/- 73 N; P = .003) or double mattress repair (290 +/- 56 N; P = .043), the Magnum Implant (163 +/- 13 N; P < .0001), and double-row repair with PushLock and Bio-Corkscrew FT anchors (163 +/- 59 N; P < .0001). Single-row double mattress repair was superior to transosseous sutures (P < .0001), the Magnum Implant (P = .009), and double-row repair with PushLock and Bio-Corkscrew FT anchors (P = .009). Lowest gap formation was found for double-row double-corkscrew repair (3.1 +/- 0.1 mm) compared to simple sutures (8.7 +/- 0.2 mm; P < .0001), the Magnum Implant (6.2 +/- 2.2 mm; P = .002), double-row repair with PushLock and Bio-Corkscrew FT anchors (5.9 +/- 0.9 mm; P = .008), and corkscrews with modified Mason-Allen sutures (6.4 +/- 1.3 mm; P = .001).
  
  
  CONCLUSIONS
  Double-row double-corkscrew anchor rotator cuff repair offered the highest failure load and smallest gap formation and provided the most secure fixation of all tested configurations. Double-loaded suture anchors using modified suture configurations achieved superior results in failure load and gap formation compared to simple suture repair and showed similar loads and gap formation with double-row repair using PushLock and Bio-Corkscrew FT anchors.
  
  
  CONCLUSIONS
  Single-row repair with modified suture configurations may lead to results comparable to several double-row fixations. If double-row repair is used, modified stitches might further minimize gap formation and increase failure load.
authors.affiliation: Department of Orthopedic Surgery, Saarland University, Homburg/Saar, Germany. olaf.lorbach@gmx.de
authors.forename: Olaf
authors.initials: O
authors.lastname: Lorbach
authors.forename: Felix
authors.initials: F
authors.lastname: Bachelier
authors.forename: Jochen
authors.initials: J
authors.lastname: Vees
authors.forename: Dieter
authors.initials: D
authors.lastname: Kohn
authors.forename: Dietrich
authors.initials: D
authors.lastname: Pape
mesh_terms: D000818:Animals; D017006:Rotator Cuff / Q000503:physiopathology / Q000601:surgery*; D013537:Sutures; D013552:Swine; D013718:Tensile Strength; D017211:Treatment Failure