Midline-Splitting Open Door Laminoplasty Using Hydroxyapatite Spacers : Comparison between Two Different Shaped Spacers.
10.3340/jkns.2012.52.1.27
- Author:
Jin Hoon PARK
1
;
Sang Ryong JEON
Author Information
1. Department of Neurological Surgery, Gangneung Asan Medical Center, University of Ulsan College of Medicine, Gangneung, Korea.
- Publication Type:Original Article
- Keywords:
Cervcial myelopathy;
Fusion rate;
Hydroxyapatite;
Laminoplasty;
Midline splitting;
Shape
- MeSH:
Animals;
Asian Continental Ancestry Group;
Durapatite;
Follow-Up Studies;
Humans;
Longitudinal Ligaments;
Lordosis;
Male;
Multivariate Analysis;
Orthopedics;
Spinal Cord Diseases
- From:Journal of Korean Neurosurgical Society
2012;52(1):27-31
- CountryRepublic of Korea
- Language:English
-
Abstract:
OBJECTIVE: Although hydroxyapatite (HA) spacer has been used for laminoplasty, there have been no reports on factors associated with fusion and on the effects of HA shape. METHODS: During January 2004 and January 2010, 45 patients with compressive cervical myelopathy underwent midline-splitting open door laminoplasty with winged (33 cases) and wingless (12 cases) HAs by a single surgeon. Minimal and mean follow up times were 12 and 28.1 months, respectively. Japanese Orthopedic Association (JOA) score was used for clinical outcome measurement. Cervical X-rays were taken preoperatively, immediately post-operatively, and after 3, 6, and 12 months and computed tomography scans were performed preoperatively, immediately post-operatively and after 12 months. Cervical lordosis, canal dimension, fusion between lamina and HA, and affecting factors of fusion were analyzed. RESULTS: All surgeries were performed on 142 levels, 99 in the winged and 43 in the wingless HA groups. JOA scores of the winged group changed from 10.4+/-2.94 to 13.3+/-2.35 and scores of the wingless group changed from 10.8+/-2.87 to 13.8+/-3.05. There was no significant difference on lordotic and canal dimensional change between two groups. Post-operative 12 month fusion rate between lamina and HA was significantly lower in the winged group (18.2 vs. 48.8% p=0.001). Multivariate analysis showed that ossification of the posterior longitudinal ligament, male gender, and wingless type HA were significantly associated with fusion. CONCLUSION: Clinical outcome was similar in patients receiving winged and wingless HA, but the wingless type was associated with a higher rate of fusion between HA and lamina at 12 months post-operatively.
