title: Locked plating of the proximal humerus using an endosteal implant.
abstract: OBJECTIVE
  To report on the use of a supplemental medial endosteal implant to prevent varus collapse and screw cutout in proximal humerus fractures treated with a laterally placed locking plate.
  
  
  METHODS
  Twenty-seven patients meeting study inclusion criteria were included in the study. Follow-up averaged 63.1 weeks (minimum 37 weeks and maximum 120 weeks). All patients were either older than 70 years or had sustained a proximal humerus fracture with medial comminution. Using the anterolateral acromial approach, a proximal humeral locking plate augmented with a medial endosteal implant (fibular allograft in 23 patients and semitubular plate in 4 patients) was used for fixation. Intraoperative fluoroscopic images and the most recent follow-up radiographs were used to measure the head-shaft angle and loss of height between the implant and the articular surface.
  
  
  RESULTS
  Only 1 of 27 patients had significant loss of reduction with collapse of the fracture into varus (4.2 mm change). Ninety-six percent of patients maintained their original reduction with an average loss of height of 1.2 mm and an average change in shaft-head angle of 2.2 degrees. There were no implant failures or screw perforations of the articular surface and no radiographic or clinical evidence of AVN.
  
  
  CONCLUSIONS
  Use of a medial endosteal implant as a supplement to a lateral locking plate is effective in maintaining operative reduction, preventing varus collapse, and implant failure in fractures with medial comminution and/or poor bone quality.
  
  
  METHODS
  Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: Hospital for Special Surgery, New York, NY 10021, USA. hettrichc@hss.edu
authors.forename: Carolyn M
authors.initials: CM
authors.lastname: Hettrich
authors.forename: Andrew
authors.initials: A
authors.lastname: Neviaser
authors.forename: Brandon S
authors.initials: BS
authors.lastname: Beamer
authors.forename: Omesh
authors.initials: O
authors.lastname: Paul
authors.forename: David L
authors.initials: DL
authors.lastname: Helfet
authors.forename: Dean G
authors.initials: DG
authors.lastname: Lorich
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001860:Bone Plates; D001863:Bone Screws; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D011859:Radiography; D012784:Shoulder Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D016896:Treatment Outcome