title: Comparison of glenohumeral contact pressures and contact areas after glenoid reconstruction with latarjet or distal tibial osteochondral allografts.
abstract: BACKGROUND
  Glenoid reconstruction with distal tibial allografts offers the theoretical advantage over Latarjet reconstruction of improved joint congruity and a cartilaginous articulation for the humeral head. Hypothesis/
  
  
  OBJECTIVE
  To investigate changes in the magnitude and location of glenohumeral contact areas, contact pressures, and peak forces after (1) the creation of a 30% anterior glenoid defect and subsequent glenoid bone augmentation with (2) a flush Latarjet coracoid graft or (3) a distal tibial osteochondral allograft. It was hypothesized that the distal tibial bone graft would best normalize glenohumeral contact areas, contact pressures, and peak forces.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Eight cadaveric shoulder specimens were dissected free of all soft tissues and randomly tested in 3 static positions of humeral abduction with a 440-N compressive load: 30°, 60°, and 60° of abduction with 90° of external rotation (ABER). Glenohumeral contact area, contact pressure, and peak force were determined sequentially using a digital pressure mapping system for (1) the intact glenoid, (2) the glenoid with a 30% anterior bone defect, and (3) the glenoid after reconstruction with a distal tibial allograft or a Latarjet bone block.
  
  
  RESULTS
  Glenoid reconstruction with distal tibial allografts resulted in significantly higher glenohumeral contact areas than reconstruction with Latarjet bone blocks in 60° of abduction (4.87 vs. 3.93 cm2, respectively; P < .05) and the ABER position (3.98 vs. 2.81 cm2, respectively; P < .05). Distal tibial allograft reconstruction also demonstrated significantly lower peak forces than Latarjet reconstruction in the ABER position (2.39 vs. 2.61 N, respectively; P < .05). Regarding the bone loss model, distal tibial allograft reconstruction exhibited significantly higher contact areas and significantly lower contact pressures and peak forces than the 30% defect model at all 3 abduction positions. Latarjet reconstruction also followed this same pattern, but differences in contact areas and peak forces between the defect model and Latarjet reconstruction in the ABER position were not statistically significant (P > .05).
  
  
  CONCLUSIONS
  Reconstruction of anterior glenoid bone defects with a distal tibial allograft may allow for improved joint congruity and lower peak forces within the glenohumeral joint than Latarjet reconstruction at 60° of abduction and the ABER position. Although these mechanical properties may translate into clinical differences, further studies are needed to understand their effects.
  
  
  CONCLUSIONS
  Glenoid bone reconstruction with a distal tibial osteochondral allograft may result in significantly improved glenohumeral contact areas and significantly lower glenohumeral peak forces than reconstruction with a Latarjet bone block, which could play a role in improving postoperative outcomes after glenoid reconstruction.
authors.affiliation: Division of Sports Medicine, Department of Orthopaedic Surgery, Rush University Medical Center, Rush Medical College of Rush University, 1611 West Harrison St, Suite 400, Chicago, IL 60612, USA.
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Bhatia
authors.forename: Geoffrey S
authors.initials: GS
authors.lastname: Van Thiel
authors.forename: Deepti
authors.initials: D
authors.lastname: Gupta
authors.forename: Neil
authors.initials: N
authors.lastname: Ghodadra
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Cole
authors.forename: Bernard R
authors.initials: BR
authors.lastname: Bach
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Shewman
authors.forename: Vincent M
authors.initials: VM
authors.lastname: Wang
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Romeo
authors.forename: Nikhil N
authors.initials: NN
authors.lastname: Verma
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Provencher
mesh_terms: D001696:Biomechanical Phenomena; D016025:Bone Transplantation / Q000379:methods*; D005260:Female; D061165:Glenoid Cavity / Q000033:anatomy & histology / Q000502:physiology / Q000601:surgery*; D006801:Humans; D051457:Hyaline Cartilage / Q000637:transplantation*; D008297:Male; D016059:Range of Motion, Articular; D012785:Shoulder Joint / Q000033:anatomy & histology / Q000502:physiology / Q000601:surgery*; D013977:Tibia / Q000637:transplantation*; D014184:Transplantation, Homologous
keywords: Latarjet; distal tibial allograft; glenoid reconstruction