title: Predicting loss of height in surgically treated displaced intra-articular fractures of the calcaneus.
abstract: OBJECTIVE
  The goal of calcaneal fracture surgery is to restore its anatomy and good foot function. However, loss of height of the subtalar joint can occur post-operatively, as expressed by a decrease in Böhler's angle (BA). The aim of this study was to identify potential factors associated with a post-operative decrease in BA.
  
  
  METHODS
  All consecutive adult patients treated with open reduction and internal fixation (ORIF) by an extended lateral approach (ELA) between 2000 and 2013 were retrospectively included. Primary outcome was the occurrence of a calcaneal collapse, defined as a postoperative decrease of ≥10° in BA. The BA was measured pre-operatively, directly following surgery and at one year follow-up. Patient characteristics (body mass index, diabetes mellitus, smoking/alcohol/substance abuse, American Society of Anaesthesiologist classification), fracture classification and treatment characteristics: per-operative increase in BA and occurrence of post-operative wound infection (POWI) were collected.
  
  
  RESULTS
  A total of 262 patients with 276 calcaneal fractures were included. A calcaneal collapse occurred in 46 cases (17%). The median preoperative BA, per-operative increase in BA and post-operative decrease in BA were, respectively, 2°, 27° and 4°. A calcaneal collapse was seen more often following a per-operative increase of >25° in BA, but no significant association was found (p = 0.056). Uni- and multivariate analysis showed that patients with substance abuse and those with POWI had significantly more calcaneal collapse (p < 0.05). No association was found between substance abuse and the occurrence of POWI (p = 0.293).
  
  
  CONCLUSIONS
  In nearly one in six patients with an intra-articular calcaneal fracture treated with ORIF by an ELA, a post-operative collapse of ≥10° was found during follow-up. Calcaneal collapse was correlated with the occurrence of a POWI and substance abuse.
authors.affiliation: Academic Medical Center, Trauma Unit, Department of Surgery, G4, University of Amsterdam, Meibergdreef 9, PO Box 22660, 1100 DD, Amsterdam, The Netherlands. m.backes@amc.nl.
authors.forename: Manouk
authors.initials: M
authors.lastname: Backes
authors.affiliation: Academic Medical Center, Trauma Unit, Department of Surgery, G4, University of Amsterdam, Meibergdreef 9, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.
authors.forename: Maarten C
authors.initials: MC
authors.lastname: Dorr
authors.affiliation: Academic Medical Center, Trauma Unit, Department of Surgery, G4, University of Amsterdam, Meibergdreef 9, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.
authors.forename: Jan S K
authors.initials: JS
authors.lastname: Luitse
authors.affiliation: Academic Medical Center, Trauma Unit, Department of Surgery, G4, University of Amsterdam, Meibergdreef 9, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.
authors.forename: Johan C
authors.initials: JC
authors.lastname: Goslings
authors.affiliation: Academic Medical Center, Trauma Unit, Department of Surgery, G4, University of Amsterdam, Meibergdreef 9, PO Box 22660, 1100 DD, Amsterdam, The Netherlands.
authors.forename: Tim
authors.initials: T
authors.lastname: Schepers
mesh_terms: D000328:Adult; D016512:Ankle Injuries / Q000601:surgery*; D002111:Calcaneus / Q000000981:diagnostic imaging / Q000293:injuries / Q000601:surgery*; D005260:Female; D005593:Fracture Fixation, Internal / Q000009:adverse effects* / Q000379:methods; D006801:Humans; D057072:Intra-Articular Fractures / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D012189:Retrospective Studies; D013380:Subtalar Joint / Q000000981:diagnostic imaging / Q000601:surgery; D013530:Surgical Wound Infection
keywords: Böhler’s angle; Calcaneal fracture; Extended lateral approach; POWI; Postoperative wound infection; Surgery