title: Outcomes Following Arthrodesis for Atlanto-Axial Osteoarthritis.
abstract: METHODS
  Retrospective analysis.
  
  
  OBJECTIVE
  We set out to evaluate the radiographic and patient-reported outcomes following C1-C2 arthrodesis for atlantoaxial osteoarthritis (AAOA) using modern instrumentation and techniques.
  
  
  BACKGROUND
  Few studies have evaluated outcomes following C1-C2 arthrodesis for AAOA using modern surgical fixation techniques.
  
  
  METHODS
  Retrospective analysis of all patients following C1-C2 arthrodesis with recalcitrant AAOA from a single center, single surgeon from 2002 to 2012. Preoperative, immediate and final follow-up postoperative radiographic images were evaluated. Patient-reported outcomes scores were assessed preoperative, 1-year, and final postoperative follow-up.
  
  
  RESULTS
  We found a total of 14 patients (13 female, 1 male) with average follow-up of 2.96 ± 2.26 years and mean age at surgery of 71.8 ± 9.3 years old. The most common construct was posterior C1-C2 bilateral screw-rod construct (SRC) (n = 9), and there were 3 patients with transarticular screw (TAS) constructs, and 2 patients with hybrid fixation (unilateral SRC and contralateral TAS). Mean change from baseline to final follow-up for Numeric Pain Rating Scale (NRS) was -4.7 ± 2.1, and Neck Disability Index (NDI) was -21.0 ± 13.6, with 11 (78.6%) patients demonstrated a substantial clinical benefit (change in NDI ≥ 10). There were no differences from baseline to all follow-up time points for SF-12 Physical and Mental Component Scores. All patients had evidence of solid C1-C2 arthrodesis and stable fixation at final follow-up, with no significant change in subaxial sagittal alignment. There were no perioperative or postoperative complications.
  
  
  CONCLUSIONS
  We report one of the largest series evaluating patient-reported outcomes in patients following arthrodesis for AAOA using modern C1-C2 fixation techniques. Our study found C1-C2 arthrodesis for AAOA to be safe and effective, with a significant improvement in patient-reported pain and neck disability and most patients reporting substantial clinical benefit.
  
  
  METHODS
  4.
authors.affiliation: Department of Orthopedic Surgery, Madigan Army Medical Center, Tacoma, WA.
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Kang
authors.affiliation: Department of Orthopedic Surgery, Columbia University Medical Center-The Spine Hospital, New York, NY.
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Lehman
authors.affiliation: Department of Orthopedic Surgery, Walter Reed National Military Medical Center, Bethesda, MD.
authors.forename: Scott C
authors.initials: SC
authors.lastname: Wagner
authors.affiliation: Department of Orthopedic Surgery, Washington University School of Medicine, St. Louis, MO.
authors.forename: Colleen
authors.initials: C
authors.lastname: Peters
authors.affiliation: Department of Orthopedic Surgery, Columbia University Medical Center-The Spine Hospital, New York, NY.
authors.forename: K Daniel
authors.initials: KD
authors.lastname: Riew
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001174:Arthrodesis / Q000379:methods; D001863:Bone Screws / Q000009:adverse effects; D002574:Cervical Vertebrae / Q000601:surgery*; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009333:Neck / Q000601:surgery*; D019547:Neck Pain / Q000209:etiology / Q000601:surgery*; D010003:Osteoarthritis / Q000601:surgery*; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000379:methods; D016896:Treatment Outcome