title: Outcome of single level anterior cervical discectomy and fusion using nano-hydroxyapatite/polyamide-66 cage.
abstract: BACKGROUND
  Cages have been widely used for the anterior reconstruction and fusion of cervical spine. Nonmetal cages have become popular due to prominent stress shielding and high rate of subsidence of metallic cages. This study aims to assess fusion with n-HA/PA66 cage following one level anterior cervical discectomy.
  
  
  METHODS
  Forty seven consecutive patients with radiculopathy or myelopathy underwent single level ACDF using n-HA/PA66 cage. We measured the segmental lordosis and intervertebral disc height on preoperative radiographs and then calculated the loss of segmental lordosis correction and cage subsidence over followup. Fusion status was evaluated on CT scans. Odom criteria, Japanese Orthopedic Association (JOA) and Visual Analog Pain Scales (VAS) scores were used to assess the clinical results. Statistically quantitative data were analyzed while Categorical data by χ(2) test.
  
  
  RESULTS
  Mean correction of segmental lordosis from surgery was 6.9 ± 3.0° with a mean loss of correction of 1.7 ± 1.9°. Mean cage subsidence was 1.2 ± 0.6 mm and the rate of cage subsidence (>2 mm) was 2%. The rate of fusion success was 100%. No significant difference was found on clinical or radiographic outcomes between the patients (n=27) who were fused by n-HA/PA66 cage with pure local bone and the ones (n=20) with hybrid bone (local bone associating with bone from iliac crest).
  
  
  CONCLUSIONS
  The n-HA/PA66 cage is a satisfactory reconstructing implant after anterior cervical discectomy, which can effectively promote bone graft fusion and prevent cage subsidence.
authors.affiliation: Department of Orthopedic Surgery, West China Hospital, Sichuan University, No. 37 Guoxue Road, Chengdu, Sichuan, China.
authors.forename: Xi
authors.initials: X
authors.lastname: Yang
authors.affiliation: Department of Orthopedic Surgery, West China Hospital, Sichuan University, No. 37 Guoxue Road, Chengdu, Sichuan, China.
authors.forename: Limin
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Orthopedic Surgery, West China Hospital, Sichuan University, No. 37 Guoxue Road, Chengdu, Sichuan, China.
authors.forename: Yueming
authors.initials: Y
authors.lastname: Song
authors.affiliation: Department of Orthopedic Surgery, West China Hospital, Sichuan University, No. 37 Guoxue Road, Chengdu, Sichuan, China.
authors.forename: Qingquan
authors.initials: Q
authors.lastname: Kong
authors.affiliation: Department of Orthopedic Surgery, West China Hospital, Sichuan University, No. 37 Guoxue Road, Chengdu, Sichuan, China.
authors.forename: Jiancheng
authors.initials: J
authors.lastname: Zeng
authors.affiliation: Department of Orthopedic Surgery, West China Hospital, Sichuan University, No. 37 Guoxue Road, Chengdu, Sichuan, China.
authors.forename: Chongqi
authors.initials: C
authors.lastname: Tu
keywords: Cervical spine; anterior fusion; discectomy; nano-hydroxyapatite/polyamide-66 cage
references.citation: Spine (Phila Pa 1976). 2000 Sep 15;25(18):2407-15
references.pmid: 10984797
references.citation: J Bone Joint Surg Am. 1959 Jan;41-A(1):1-6
references.pmid: 13620682
references.citation: J Orthop Traumatol. 2010 Jun;11(2):99-103
references.pmid: 20532943
references.citation: Orthopedics. 2012 Jan 16;35(1):e66-73
references.pmid: 22229617
references.citation: Spine (Phila Pa 1976). 1999 Aug 1;24(15):1604-10
references.pmid: 10457582
references.citation: Orthopedics. 1988 Jun;11(6):931-4
references.pmid: 3387340
references.citation: J Orthop Traumatol. 2011 Dec;12(4):201-5
references.pmid: 22089645
references.citation: J Spinal Disord Tech. 2010 Jul;23(5):310-6
references.pmid: 20124907
references.citation: J Neurosurg Spine. 2005 May;2(5):521-5
references.pmid: 15945426
references.citation: J Spinal Disord Tech. 2006 Jul;19(5):353-7
references.pmid: 16826008
references.citation: Spine (Phila Pa 1976). 1993 Oct 15;18(14):2106-7
references.pmid: 8272967
references.citation: Biomaterials. 2002 Dec;23(24):4787-91
references.pmid: 12361617
references.citation: Int J Nanomedicine. 2010 May 13;5:331-5
references.pmid: 20517477
references.citation: J Bone Joint Surg Am. 1958 Jun;40-A(3):607-24
references.pmid: 13539086
references.citation: J Spinal Disord Tech. 2008 Oct;21(7):489-92
references.pmid: 18836360
references.citation: Clin Orthop Relat Res. 2005 Jan;(430):108-16
references.pmid: 15662311
references.citation: J Bone Joint Surg Br. 2003 Sep;85(7):1019-25
references.pmid: 14516039
references.citation: Spine (Phila Pa 1976). 2003 Jan 15;28(2):134-9
references.pmid: 12544929
references.citation: Spine (Phila Pa 1976). 2003 Aug 1;28(15 Suppl):S2-7
references.pmid: 12897467
references.citation: J Mater Sci Mater Med. 2003 Jul;14(7):655-60
references.pmid: 15348430
references.citation: J Clin Neurosci. 2012 Apr;19(4):536-40
references.pmid: 22305868
references.citation: Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2007 Oct;21(10):1084-8
references.pmid: 17990775
references.citation: J Neurosurg Spine. 2006 Jun;4(6):447-53
references.pmid: 16776355
references.citation: J Neurosurg Spine. 2006 Oct;5(4):287-93
references.pmid: 17048764
references.citation: J Spinal Disord Tech. 2010 Jul;23(5):321-7
references.pmid: 20084029
references.citation: Clin Orthop Relat Res. 2002 Jan;(394):27-38
references.pmid: 11795743