title: Acromioclavicular joint reconstruction using a tendon graft: a biomechanical study comparing a novel "sutured throughout" tendon graft to a standard tendon graft.
abstract: BACKGROUND
  With a recurrence rate of over 30%, techniques that offer stronger acromioclavicular (AC) joint reconstruction through increased graft strength may provide longevity. The purpose of our study was to determine the biomechanical strength of a novel tendon graft sutured throughout compared to a native tendon graft in Grade 3 anatomical AC joint reconstruction.
  
  
  METHODS
  For this in vitro experiment, nine paired (n = 18) embalmed cadaveric AC joints of three males and six females (age 86 years, range 51-94 years) were harvested. Anatomic repair with fresh bovine Achilles tendon grafts without bone block was simulated. Specimens were divided into two groups; with group 1 using grafts with ultra-high molecular-weight polyethylene (UHMWPE) suture ran throughout the entire length. In group 2, reconstruction with only native allografts was performed. The distal scapula and humerus were casted in epoxy compound and mounted on the mechanical testing machine. Tensile tests were performed using a mechanical testing machine at the rate of 50 mm/min. Maximum load and displacement to failure were collected.
  
  
  RESULTS
  The average load to failure was significantly higher for group 1 compared to group 2, with mean values of 437.5 N ± 160.7 N and 94.4 N ± 43.6 N, (p = 0.001). The average displacement to failure was not significantly different, with 29.7 mm ± 10.6 mm in group 1 and 25 mm ± 9.1 mm in group 2 (p = 0.25).
  
  
  CONCLUSIONS
  We conclude that a UHMWPE suture reinforced graft can provide a 3.6 times stronger AC joint reconstruction compared to a native graft.
authors.affiliation: Department of Orthopaedics, SUNY Downstate Medical Center 450 Clarkson Avenue, MSC 30 Brooklyn NY 11203 USA.
authors.forename: Qais
authors.initials: Q
authors.lastname: Naziri
authors.affiliation: Department of Orthopaedics, SUNY Downstate Medical Center 450 Clarkson Avenue, MSC 30 Brooklyn NY 11203 USA.
authors.forename: Nadine
authors.initials: N
authors.lastname: Williams
authors.affiliation: Department of Orthopaedics, SUNY Downstate Medical Center 450 Clarkson Avenue, MSC 30 Brooklyn NY 11203 USA.
authors.forename: Westley
authors.initials: W
authors.lastname: Hayes
authors.affiliation: Department of Orthopaedics, SUNY Downstate Medical Center 450 Clarkson Avenue, MSC 30 Brooklyn NY 11203 USA.
authors.forename: Bhaveen H
authors.initials: BH
authors.lastname: Kapadia
authors.affiliation: Department of Orthopaedics, SUNY Downstate Medical Center 450 Clarkson Avenue, MSC 30 Brooklyn NY 11203 USA.
authors.forename: Dipal
authors.initials: D
authors.lastname: Chatterjee
authors.affiliation: Department of Orthopaedics, SUNY Downstate Medical Center 450 Clarkson Avenue, MSC 30 Brooklyn NY 11203 USA.
authors.forename: William P
authors.initials: WP
authors.lastname: Urban
keywords: Acromioclavicular joint; Biomechanics; Coracoclavicular ligament; Graft augmentation; UHMWPE suture