title: Outcomes of anatomic shoulder arthroplasty in primary osteoarthritis in type B glenoids.
abstract: BACKGROUND
  Primary glenohumeral osteoarthritis with posterior wear of the glenoid and posterior subluxation of the humerus (Walch type B) presents a challenge to the treating surgeon. Our hypothesis was that glenoids with biconcavity (B2) would be associated with worse outcomes (functional scores and complications) than B1 glenoids.
  
  
  METHODS
  We retrospectively analyzed prospectively collected data on 112 anatomic total shoulder arthroplasties (104 patients) with B glenoids. Preoperative computed tomography identified 64 B1 glenoids and 48 B2 glenoids (50 and 37 available for follow-up).
  
  
  RESULTS
  A significant difference between B1 and B2 glenoids was noted in average retroversion (11° vs. 16°; P < .001) and average posterior humeral subluxation (65% vs. 75%; P < .001). No significant difference was seen in mean age (69.5 vs. 69.2 years) or body mass index (28.5 vs. 27.4) at time of surgery. At average follow-up of 60 months (range, 23-120 months), glenoid component radiolucencies (51.6%, B1; 47.9%, B2), range of motion, preoperative and postoperative scores of the shortened Disabilities of the Arm, Shoulder, and Hand questionnaire, and patient satisfaction were not significantly different between the 2 groups. Four revisions (4.6%) were documented for acute postoperative infection (2.3%), subscapularis failure (1.1%), and glenoid loosening (1.1%).
  
  
  CONCLUSIONS
  Although biconcave glenoids commonly have more severe retroversion and posterior subluxation of the humerus, we were unable to find a clinical or radiographic difference in outcome of patients with B1 or B2 glenoids treated with anatomic total shoulder arthroplasty at intermediate-term follow-up. Continued clinical and radiographic follow-up of these cohorts will be necessary to assess any future divergence in outcome.
authors.affiliation: Sterling Ridge Orthopaedics and Sports Medicine, The Woodlands, TX, USA.
authors.forename: Paul C
authors.initials: PC
authors.lastname: Chin
authors.affiliation: Shiley Center for Orthopaedic Research and Education at Scripps Clinic, La Jolla, CA, USA.
authors.forename: Michael E
authors.initials: ME
authors.lastname: Hachadorian
authors.affiliation: Shiley Center for Orthopaedic Research and Education at Scripps Clinic, La Jolla, CA, USA.
authors.forename: Pamela A
authors.initials: PA
authors.lastname: Pulido
authors.affiliation: Shiley Center for Orthopaedic Research and Education at Scripps Clinic, La Jolla, CA, USA.
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Munro
authors.affiliation: Shiley Center for Orthopaedic Research and Education at Scripps Clinic, La Jolla, CA, USA; Department of Orthopaedic Surgery, Balikesir University, Balikesir, Turkey.
authors.forename: Gokhan
authors.initials: G
authors.lastname: Meric
authors.affiliation: Shiley Center for Orthopaedic Research and Education at Scripps Clinic, La Jolla, CA, USA; Division of Orthopaedics, Scripps Clinic, La Jolla, CA, USA. Electronic address: hhoenecke@gmail.com.
authors.forename: Heinz R
authors.initials: HR
authors.lastname: Hoenecke
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000601:surgery*; D017060:Patient Satisfaction; D016059:Range of Motion, Articular; D012086:Reoperation; D012189:Retrospective Studies; D012783:Shoulder Dislocation / Q000601:surgery*; D012785:Shoulder Joint / Q000601:surgery*
keywords: Anatomic total shoulder arthroplasty; biconcave glenoid; primary osteoarthritis; type B glenoid