title: Reconstruction of 25 and 50 % subscapularis tears: a single anchor with a double-mattress suture is sufficient for the reconstruction.
abstract: OBJECTIVE
  Evaluation of the biomechanical performance of repairs of 25 % (Fox/Romeo II) and 50 % (Fox/Romeo III) full-thickness subscapularis tears using a single-suture anchor.
  
  
  METHODS
  Six pairs of human cadaver specimens were used for the testing. Artificial subscapularis tears were created in order to simulate a 25 % (6) and a 50 % (6) full-thickness tear. The reconstructions were made with a double-loaded suture anchor (5.5-mm Bio-Corkscrew with two No. 2 Fiberwire) creating a double-mattress suture repair. Reconstructions were cyclically loaded from 10 to 60 N. The load was increased stepwise up to 100 and 180 N. Cyclic displacement (means + standard dev.) as well as load-to-failure was determined, and mode of failure was recorded.
  
  
  RESULTS
  In the reconstructed shoulders at 60 N, a mean cyclic displacement of 3.2 ± 0.7 mm was found in the 25 % tear, 2.6 ± 0.6 mm in the 50 % tear. At 100 N, 5.1 ± 1.2 mm was seen in the 25 % tear and 4.3 ± 0.3 mm in the 50 % tear. At highest load of 180 N, 7.6 ± 2.2 mm was recorded in the 25 % tear, 6.5 ± 0.8 mm was found in the 50 % tear. Ultimate failure load was 486 ± 167 N in the 25 % tear and 455 ± 213 N in the 50 % tear. Statistically significant differences between the tested repairs were seen neither in cyclic displacement nor in ultimate failure loads (p > 0.05). Mode of failure revealed bone fractures and anchor pull-out as major cause in the 25 % group, whereas failure of the suture-tendon interface was the major cause of failure in the 50 % group.
  
  
  CONCLUSIONS
  Subscapularis repair using a single double-loaded suture anchor revealed similar biomechanical performance in 25 % compared to 50 % full-thickness subscapularis tears. With increased tear size, however, an optimized suture-tendon interface seems to become more relevant in order to decrease failure rate of the repair.
  
  
  CONCLUSIONS
  A single double-loaded suture anchor provides sufficient biomechanical strength even in Fox/Romeo grade III tears of the subscapularis tendon. However, a modified suture configuration is recommended, especially in grade III tears as the suture-tendon interface is the weakest point of the construct.
authors: Department of Orthopaedic Surgery, Saarland University, Kirrberger Str, Geb. 37, 66421, Homburg (Saar), Germany. olaf.lorbach@gmx.de.
authors: Olaf
authors: O
authors: Lorbach
authors: Department of Orthopaedic Surgery, Saarland University, Kirrberger Str, Geb. 37, 66421, Homburg (Saar), Germany.
authors: Christian
authors: C
authors: Trennheuser
authors: Department of Orthopaedic and Trauma Surgery, Klinikum Ernst von Bergmann, Potsdam/Bad Belzig, Germany.
authors: Matthias
authors: M
authors: Kieb
authors: Department of Orthopaedic Surgery, Marburg University, Marburg, Germany.
authors: Turgay
authors: T
authors: Efe
authors: Department of Orthopaedic Surgery, Saarland University, Kirrberger Str, Geb. 37, 66421, Homburg (Saar), Germany.
authors: Dieter
authors: D
authors: Kohn
authors: Department of Orthopaedic Surgery, Saarland University, Kirrberger Str, Geb. 37, 66421, Homburg (Saar), Germany.
authors: Konstantinos
authors: K
authors: Anagnostakos
mesh_terms: D001696:Biomechanical Phenomena; D002102:Cadaver; D006801:Humans; D019651:Plastic Surgery Procedures / Q000379:methods*; D017006:Rotator Cuff / Q000601:surgery; D000070636:Rotator Cuff Injuries / Q000601:surgery*; D053441:Suture Anchors; D013536:Suture Techniques; D013537:Sutures; D016474:Weight-Bearing
keywords: Cyclic loading; Rotator cuff; Single-row repair; Subscapularis tear