Asian Spine J.  2018 Dec;12(6):1078-1084. 10.31616/asj.2018.12.6.1078.

Novel Hybrid Hydroxyapatite Spacers Ensure Sufficient Bone Bonding in Cervical Laminoplasty

• Tanaka N
• Nakanishi
• Kamei N
• Nakamae T
• Kotaka S
• Fujimoto Y
• Ochi M
• Adachi N

• KMID: 2430641
• DOI: http://doi.org/10.31616/asj.2018.12.6.1078

Abstract

STUDY DESIGN: Prospective observational study. PURPOSE: This prospective analysis aimed to evaluate the efficacy and bone-bonding rate of hybrid hydroxyapatite (HA) spacers in expansive laminoplasty. OVERVIEW OF LITERATURE: Various types of spacers or plates have been developed for expansive laminoplasty.
METHODS
Expansive open-door laminoplasty was performed in 146 patients with cervical myelopathy; 450 hybrid HA spacers and 41 autogenous bone spacers harvested from the spinous processes were grafted into the opened side of each lamina. The patients were followed up using computed tomography (CT), and their bone-bonding rates for hybrid HA and autogenous spacers, bone-fusion rates of the hinges of the laminae, and complications associated with the implants were then examined.
RESULTS
Clinical symptoms significantly improved in all patients, and no major complications related to the procedure were noted. The hybrid HA spacers exhibited sufficient bone bonding on postoperative CT. The hinges completely fused in over 95% patients within 1 year of the procedure. Only 4 spacers (0.9%) developed lamina sinking, and most expanded laminae maintained their positions without sinking or floating throughout the follow-up period.
CONCLUSIONS
Hybrid HA spacers contributed to high bone-fusion rates of the spacers and hinges of the laminae, and no complications were associated with their use. Cervical laminoplasty with these spacers is safe and simple, and it yields sufficient fixation strength while ensuring sufficient bone bonding during the immediate postoperative period.

Keyword

Cervical vertebrae; Laminoplasty; Myelopathy compressive; Calcium hydroxyapatite

MeSH Terms

Cervical Vertebrae
Durapatite*
Female
Follow-Up Studies
Humans
Laminoplasty*
Observational Study
Postoperative Period
Prospective Studies
Spinal Cord Diseases
Transplants
Durapatite