title: Porous/dense composite hydroxyapatite for anterior cervical discectomy and fusion.
abstract: METHODS
  A prospective analysis
  
  
  OBJECTIVE
  Our aim was to investigate the efficacy of new synthetic porous/dense composite hydroxyapatite (HA) for use in anterior cervical discectomy and fusion (ACDF).
  
  
  BACKGROUND
  Iliac crest bone graft (ICBG) has been traditionally used as the "gold standard" for ACDF. The significant complication rate associated with harvesting tricortical ICBG, however, has encouraged development of alternative graft substitutes.
  
  
  METHODS
  The morphology of the porous/dense HA was observed by scanning electron microscopy (SEM), and the in vitro compressive strength of the composite HA was measured. From April 2005, 51 consecutive patients underwent 81 levels of ACDF using the composite HA with percutaneously harvested trephine bone chips. Clinical and radiological evaluation was performed during the postoperative hospital stay and at follow-up. Furthermore, the outcomes in ACDF using the composite HA were compared with those using tricortical ICBG.
  
  
  RESULTS
  The SEM images demonstrated 100- to 300-μm pores (approximately 40% of porosity) in the porous layers of the HA. The compressive strength of the composite HA was 203.1 ± 4.1 MPa. In the clinical study, the demographic data of the patients were similar in HA and ICBG groups. The fusion rates in HA group were comparable with those in ICBG group. The cervical lordosis was enhanced postoperatively in both groups and well preserved at 2-year follow-up without significant differences between the groups. The intraoperative blood loss in HA group was significantly lesser than that in ICBG group. Donor site complications were found in 29.2% of the patients in ICBG group, whereas no donor site morbidity was found in HA group. No major collapse or fragmentation of the composite HA was found.
  
  
  CONCLUSIONS
  The hybrid graft of composite HA and percutaneously harvested trephine chips seemed promising as a graft substitute for ACDF.
  
  
  METHODS
  4.
authors.affiliation: Department of Orthopaedic and Spinal Surgery, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan. yoshii.orth@tmd.ac.jp
authors.forename: Toshitaka
authors.initials: T
authors.lastname: Yoshii
authors.forename: Masato
authors.initials: M
authors.lastname: Yuasa
authors.forename: Shinichi
authors.initials: S
authors.lastname: Sotome
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Yamada
authors.forename: Kyohei
authors.initials: K
authors.lastname: Sakaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Hirai
authors.forename: Takashi
authors.initials: T
authors.lastname: Taniyama
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Inose
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Kato
authors.forename: Yoshiyasu
authors.initials: Y
authors.lastname: Arai
authors.forename: Shigenori
authors.initials: S
authors.lastname: Kawabata
authors.forename: Shoji
authors.initials: S
authors.lastname: Tomizawa
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Enomoto
authors.forename: Kenichi
authors.initials: K
authors.lastname: Shinomiya
authors.forename: Atsushi
authors.initials: A
authors.lastname: Okawa
mesh_terms: D000328:Adult; D000368:Aged; D016025:Bone Transplantation / Q000379:methods; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D017586:Diskectomy / Q000379:methods*; D017886:Durapatite / Q000737:chemistry / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007085:Ilium / Q000601:surgery; D008297:Male; D008855:Microscopy, Electron, Scanning; D008875:Middle Aged; D016062:Porosity; D011446:Prospective Studies; D013123:Spinal Fusion / Q000379:methods*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D017886:Durapatite