Journal List > J Korean Neurotraumatol Soc > v.7(2) > 1084100

J Korean Neurotraumatol Soc. 2011 Oct;7(2):63-67. Korean.
Published online October 31, 2011.
Copyright © 2011 Korean Neurotraumatology Society
Clinical and Radiological Outcome Analysis on Anterior Cervical Discectomy and Interbody Fusion Using Hydroxyapatite Block
Jin Gyeong Ha, MD, Jin Hoon Park, MD and Sang Ryong Jeon, MD
Department Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.

Address for correspondence: Sang Ryong Jeon, MD, PhD. Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul 138-736, Korea. Tel: +82-2-3010-3550, Fax: +82-2-476-6738, Email:
Received March 29, 2011; Revised August 22, 2011; Accepted August 22, 2011.



Although use of autologous iliac bone graft in anterior cervical discectomy and fusion (ACDF) for cervical degenerative diseases remain standard surgical procedure, donor site morbidity are still concerns. Several synthetic graft materials have been developed to prevent this complication. This is retrospective study of clinical and radiological outcomes of ACDF using synthetic hydroxyapatite (HA) block to evaluate the efficacy.


From May 2009 to June 2010, twenty-one patients (M 11 ; F 10) were enrolled in this study and 35 segments were involved. All patients were performed ACDF using HA block and plating system. Indications of surgery were radiculopathy caused by degenerative cervical spondylosis with or without myelopathy. The mean period of clinical follow-up was 6.6 months (range from 6 to 12 months). The change of Visual Analogue Scale (VAS) and Neck Disability Index (NDI) at 6 month were used for clinical outcome analysis. Cervical spine radiographs including dynamic views were obtained at postoperative 3 day, 1, 3, 6 months in all patients to measure the change of disc height, overall and segmental lordosis, segmental motion. Computed tomography was done at postoperative 6 month in all patients to confirm the radiological fusion.


Mean VAS and NDI score changed from 8.2 to 2.7 and from 23.4 to 10.5, respectively. The mean disc height change was from 4.5 to 7.1. Cervical lordosis and segmental lordosis changes were from 24.4 to 24.5 and from 3.93 to 4.57, respectively. Complete interbody fusion was achieved in 95.2% of patients. There was one case of non-fusion patient.


HA block is very efficient graft material in achieving cervical fusion, maintaining intervertebral disc height for ACDF. Further follow up study should be needed to evaluate the efficacy of this material.

Keywords: Bone fusion; Cervical lordosis; Disc height; Hydroxyapatite block; Cervical intervertebral disk


A: Mean height=(A+B)/2, A=anterior disc height, B=posterior disc height. B: C spine Stress view.
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VAS scores (A) and NDI (B) scores were decreased through the follow-up period since surgery. VAS: Visual Analogue Scale, NDI: Neck Disability Index.
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A: Disc height. Disc height increased after surgery, later decreasing but not returning to preoperative levels. B: Cervical lordosis. Cervical lordosis decreased after surgery, later returning to preoperative levels. C: Segmental lordosis. Segmental lordosis increased immediately after surgery, later decreasing but not returning to preoperative levels.
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A 52-year-old man who present with cervical radiculopathy and underwent ACDF with HA block. C spine CT scan at A immediately postoperative, B postoperative 6 months visits. Bone briding was formed between vertebral endplates (arrows). ACDF: anterior cervical discectomy and fusion, HA: hydroxyapatite.
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Baseline demographic and clinical characteristics
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Non-parametric analysis on surgical outcome (VAS)
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Non-parametric analysis on surgical outcome (NDI)
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The authors have no financial conflicts of interest.

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