title: Complications of posterior cervical plating.
abstract: METHODS
  This retrospective clinical study evaluates complications occurring during or immediately after surgery of posterior cervical plating.
  
  
  OBJECTIVE
  The present study quantifies risks associated with posterior cervical plating using lateral mass screw fixation. The observed clinical complications are compared with theoretical risks previously studied in cadavers. Unanticipated complications are identified.
  
  
  BACKGROUND
  There are many reports that describe posterior cervical plating and attempt to describe the indications for using this type of fixation, but few studies have discussed the clinical complications incurred by application of these plates and screws.
  
  
  METHODS
  Seventy-eight consecutive patients whose treatment included posterior cervical lateral mass plating were independently reviewed to identify associated complications. The average patient age was 52.9 years, and the average follow-up period was 2 years (range, 10-47 months). Multiple indications for surgery were present, but complex reconstructive procedures were required in 70.5% of cases. Complication rates were calculated as either a percentage of the number of screws inserted or as a percentage of the number of cases performed or both.
  
  
  RESULTS
  Six hundred fifty-four screws were inserted--an average of 8.4 screws per patient. Complication rates as a function of the number of screws inserted included nerve root injury, 0.6%; facet violations, 0.2%; vertebral artery injury, 0%; broken screw, 0.3%; screw avulsion, 0.2%; and screw loosening 1.1%. Complications as a percentage of the number of cases performed included spinal cord injury, 2.6%; iatrogenic foraminal stenosis, 2.6%; broken plate, 1.3%; lost reduction, 2.6%; adjacent segment degeneration, 3.8%; infection, 1.3%; and pseudoarthrosis, 1.4%.
  
  
  CONCLUSIONS
  Cadaveric work has predicted certain anatomic complication rates associated with lateral mass screw insertion. This study finds the risk of lateral mass screw insertion to be considerably less than predicted in vitro. The present study reports other complications that were not predicted in laboratory studies.
authors.affiliation: Department of Orthopaedics, Emory University School of Medicine, Atlanta, Georgia, USA.
authors.forename: J G
authors.initials: JG
authors.lastname: Heller
authors.forename: D H
authors.initials: DH
authors.lastname: Silcox
authors.forename: C E
authors.initials: CE
authors.lastname: Sutterlin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001860:Bone Plates / Q000009:adverse effects*; D001863:Bone Screws; D002574:Cervical Vertebrae / Q000601:surgery*; D004868:Equipment Failure; D005500:Follow-Up Studies; D005593:Fracture Fixation, Internal / Q000009:adverse effects; D006801:Humans; D007796:Laminectomy; D008875:Middle Aged; D012189:Retrospective Studies; D013122:Spinal Diseases / Q000601:surgery; D013123:Spinal Fusion / Q000009:adverse effects* / Q000379:methods