title: A systematic review of locking plate fixation of proximal humerus fractures.
abstract: OBJECTIVE
  Technique for the fixation of two, three, and four part proximal humerus fractures has rapidly shifted towards the use of specially contoured proximal humerus locking plates. The purpose of this study is to evaluate the short to medium term functional results and common complications associated with the fixation of proximal humerus fractures with locking plates.
  
  
  METHODS
  The PubMed and EMBASE databases were used to perform a systematic review of the English literature to assess the functional results and complications associated with proximal humerus locking plates. Our inclusion criteria were proximal humerus fracture due to trauma (excluding pathologic fractures), patients greater than 18 years of age, more than 15 patients in the study or subgroup of interest, at least 18 months follow-up, at least one relevant functional outcome score, and quality outcome score of at least 5/10. Studies that did not meet these criteria were excluded. All institutional, author, and journal information was concealed to minimize reviewer bias.
  
  
  RESULTS
  Twelve studies including 514 patients met the inclusion criteria. At most recent follow-up patients achieved a mean Constant score of 74 and a mean DASH score of 27. The overall rate of complications was 49% including varus malunion, 33% excluding varus malunion, and reoperation rate was 14%. The most common complications included varus malunion 16%, AVN 10%, screw perforation of the humeral head into the joint 8%, subacromial impingement 6%, and infection 4%.
  
  
  CONCLUSIONS
  Fixation of proximal humerus fractures with proximal humerus locking plates is associated with a high rate of complications and reoperation. Further study is needed to determine what technical errors and patient characteristics are risk factors for failure of this now common fixation technique.
authors.affiliation: University of California, San Francisco, Department of Orthopaedic Surgery, Sports Medicine and Shoulder Surgery Service, 1500 Owens Street, San Francisco, CA 94158, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Sproul
authors.forename: Jaicharan J
authors.initials: JJ
authors.lastname: Iyengar
authors.forename: Zlatko
authors.initials: Z
authors.lastname: Devcic
authors.forename: Brian T
authors.initials: BT
authors.lastname: Feeley
mesh_terms: D000328:Adult; D001860:Bone Plates / Q000009:adverse effects; D005260:Female; D005593:Fracture Fixation, Internal / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000601:surgery*; D012784:Shoulder Fractures / Q000601:surgery*; D016896:Treatment Outcome