title: Clinical and radiological analysis of Bryan cervical disc arthroplasty: eight-year follow-up results compared with anterior cervical discectomy and fusion.
abstract: Bryan cervical disc arthroplasty has been reported with satisfactory short- and medium-term clinical results. However, the long-term clinical and radiographic outcomes are seldom reported. The purpose of this study was to compare the eight-year follow-up results in patients who underwent Bryan disc arthroplasty with patients received ACDF, and assess the incidence of heterotopic ossification (HO) and its effect on clinical outcome and mobility of the device.
  
  
  
  Thirty-one patients underwent Bryan disc arthroplasty, and 35 patients underwent ACDF were included in the study. The Japanese Orthopedic Association (JOA) scores, neck disability index (NDI), visual analogue scale (VAS) of neck and arm pain, and the radiographs were used to evaluate the outcomes. The heterotopic ossification (HO) was determined by CT scan and was classified into three subgroups to compare the related effect. Adjacent segment degeneration (ASD) was also observed.
  
  
  
  At final follow-up, there were no significant differences in JOA scores between two groups, but the improvement in NDI and neck or arm VAS were significantly greater in the Bryan disc cohort. The range of motion at the index level was 7.0° in Bryan group, while 100 % bone fusion were achieved in ACDF group. HO was observed in 18 (51.4 %) levels. There were more restricted movement of the prosthesis and slight higher rate of axial pain in patients with severe-HO (grade III and IV). Fourteen (28.6 %) levels developed ASD in Bryan group, which was significantly lower than that (58.6 %) in ACDF group.
  
  
  
  At eight year follow-up, the clinical and radiographic outcomes of Bryan cervical disc arthroplasty compared favorably to those of ACDF. It avoided accelerated adjacent segment degeneration by preserving motion. However, severe HO restricted the ROM of the index levels and maybe associated with post-operative axial pain.
authors.affiliation: From the Department of Spine Surgery, and The Key Laboratory of Orthopedic Biomechanics of Hebei Province, The Third Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Lei
authors.affiliation: From the Department of Spine Surgery, and The Key Laboratory of Orthopedic Biomechanics of Hebei Province, The Third Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Yaming
authors.initials: Y
authors.lastname: Liu
authors.affiliation: From the Department of Spine Surgery, and The Key Laboratory of Orthopedic Biomechanics of Hebei Province, The Third Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: From the Department of Spine Surgery, and The Key Laboratory of Orthopedic Biomechanics of Hebei Province, The Third Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Jiaxin
authors.initials: J
authors.lastname: Xu
authors.affiliation: From the Department of Spine Surgery, and The Key Laboratory of Orthopedic Biomechanics of Hebei Province, The Third Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Ma
authors.affiliation: From the Department of Spine Surgery, and The Key Laboratory of Orthopedic Biomechanics of Hebei Province, The Third Hospital of Hebei Medical University, Shijiazhuang, China.
authors.forename: Linfeng
authors.initials: L
authors.lastname: Wang
authors.affiliation: From the Department of Spine Surgery, and The Key Laboratory of Orthopedic Biomechanics of Hebei Province, The Third Hospital of Hebei Medical University, Shijiazhuang, China. shenyonglaoshi@126.com.|Department of Spine Surgery, Third Hospital of HeBei Medical University, 139 Ziqiang Rd, Shijiazhuang, Hebei Province, 050051, China. shenyonglaoshi@126.com.
authors.forename: Yong
authors.initials: Y
authors.lastname: Shen
mesh_terms: D000328:Adult; D001178:Arthroplasty / Q000009:adverse effects / Q000379:methods*; D002574:Cervical Vertebrae / Q000601:surgery*; D017586:Diskectomy / Q000009:adverse effects / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009999:Ossification, Heterotopic / Q000453:epidemiology* / Q000209:etiology; D010147:Pain Measurement; D019736:Prostheses and Implants / Q000009:adverse effects; D016059:Range of Motion, Articular; D013123:Spinal Fusion / Q000009:adverse effects / Q000379:methods*; D016896:Treatment Outcome
keywords: Anterior cervical discectomy and fusion; Bryan disc; Cervical arthroplasty; Clinical outcome; Heterotopic ossification; Movement