title: Comparison of dysphagia between cervical artificial disc replacement and fusion: data from a randomized controlled study with two years of follow-up.
abstract: METHODS
  Prospective randomized controlled trial.
  
  
  OBJECTIVE
  To determine and explain any differences in self-reported dysphagia between patients treated with artificial disc replacement and anterior cervical decompression and fusion (ACDF).
  
  
  BACKGROUND
  Dysphagia after anterior cervical spine surgery has in previous studies been evaluated regarding different influencing factors. Surgical technique, number of treated levels, and type of implant has been shown to be of possible importance.
  
  
  METHODS
  One hundred thirty-six patients from a randomized controlled trial between artificial disc replacement and ACDF in 1 or 2 surgical levels were evaluated regarding dysphagia. Evaluation was done with the dysphagia short questionnaire preoperatively, at 4 weeks, 3 months, and 1 and 2 years postoperatively. Reconstruction in the artificial disc replacement group was performed with the Discover artificial disc. Bone graft and anterior plating was used in the ACDF group. Type of implant was blinded to the patients and the surgeon until time of implantation.
  
  
  RESULTS
  Demographics and dysphagia short questionnaire levels were similar in both groups preoperative. At 4 weeks of follow-up postoperatively, dysphagia was significantly higher in both groups than baseline levels, P < 0.01. No significant differences were seen between the groups until follow-up at 2 years, which showed significantly higher dysphagia short questionnaire levels in the ACDF group, P = 0.04. The difference was statistically significant in both patients treated with 1- and 2-level surgery, P = 0.029 and P = 0.032, respectively. A logistic regression model showed a stronger association to type of implant than to number of surgical levels. Duration of surgery was highly associated to number of surgical levels but did not differ significantly between types of implant.
  
  
  CONCLUSIONS
  Long-term postoperative dysphagia could be explained by bulk of implant or decreased motion in the cervical spine. However, it is doubtful if differences between the groups in this study can be interpreted as a clinically important difference.
  
  
  METHODS
  2.
authors.affiliation: *Department of Molecular Medicine and Surgery, Karolinska Institute, Stockholm, Sweden †Stockholm Spine Center, Löwenströmska Hospital, Upplands Väsby, Sweden; and ‡Department of Orthopedic Surgery, Uppsala University Hospital, Uppsala, Sweden.
authors.forename: Martin
authors.initials: M
authors.lastname: Skeppholm
authors.forename: Claes
authors.initials: C
authors.lastname: Olerud
mesh_terms: D000328:Adult; D002574:Cervical Vertebrae / Q000601:surgery; D019299:Decompression, Surgical / Q000009:adverse effects / Q000379:methods; D003680:Deglutition Disorders / Q000175:diagnosis* / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000175:diagnosis* / Q000209:etiology; D011446:Prospective Studies; D013123:Spinal Fusion / Q000009:adverse effects / Q000379:methods*; D013997:Time Factors; D059145:Total Disc Replacement / Q000009:adverse effects / Q000379:methods*; D016896:Treatment Outcome