title: Does the "bumper" created during Bankart repair contribute to shoulder stability?
abstract: BACKGROUND
  The aim of this study was to determine the optimal repair configuration for anterior shoulder instability after a labral tear.
  
  
  METHODS
  Nine fresh, frozen shoulders were used. With a 50-N axial force, the humeral head was translated anteriorly, and the translational force was measured. The measurement was performed with the capsule intact, after creating a Bankart lesion, and after the Bankart repair at 5 different positions: glenoid rim, glenoid surface-2 mm (on the glenoid surface 2 mm from the glenoid rim), glenoid surface-5 mm, scapular neck-2 mm (on the scapular neck 2 mm from the glenoid rim), and scapular neck-5 mm. Glenoid rim fixation was done with and without a "bumper." The "bumper" was created by plicating the capsule to form a thickened mass of tissue.
  
  
  RESULTS
  The translational force was restored to the intact level after the glenoid rim fixation. However, there was no significant difference in force after the Bankart repair with and without a "bumper" nor after the glenoid rim fixation and glenoid surface-2 mm. The force significantly decreased after scapular neck-2 mm and scapular neck-5 mm compared with the glenoid rim fixation.
  
  
  CONCLUSIONS
  The anchor fixation on the glenoid face does not increase the translational force compared with the glenoid rim placement, but the placement on the scapular neck decreases the translational force.
authors.affiliation: Biomechanics Laboratory, Division of Orthopedic Research, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Yamamoto
authors.forename: Takayuki
authors.initials: T
authors.lastname: Muraki
authors.forename: John W
authors.initials: JW
authors.lastname: Sperling
authors.forename: Scott P
authors.initials: SP
authors.lastname: Steinmann
authors.forename: Eiji
authors.initials: E
authors.lastname: Itoi
authors.forename: Robert H
authors.initials: RH
authors.lastname: Cofield
authors.forename: Kai-Nan
authors.initials: KN
authors.lastname: An
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000601:surgery*; D008297:Male; D008422:Materials Testing; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods*; D012785:Shoulder Joint / Q000601:surgery*; D053441:Suture Anchors