Hydroxyapatite-bioactive glass ceramic composite as stand-alone graft substitute for posterolateral fusion of lumbar spine: a prospective, matched, and controlled study.
METHODS
Prospective, matched, and controlled study.


OBJECTIVE
To evaluate the efficacy of hydroxyapatite-bioactive glass ceramic composite (Chitra-HABg) as a stand-alone graft substitute in promoting posterolateral fusion in the lumbar spine as compared with autologous bone.


BACKGROUND
The use of ceramics as stand-alone graft substitutes in posterolateral fusion remains controversial. The Chitra-HABg is a new composite that has undergone clinical trials in various orthopedic applications with excellent clinical and radiologic outcomes.


METHODS
Twenty-four patients underwent instrumented posterolateral fusion, with Chitra-HABg laid on the left intertransverse bed and autogenous graft on the right side. The primary outcome measure was radiologic consolidation of the graft, and secondary outcome measures were the work status and the Modified Oswestry Disability index. The McNamara and Student chi test were applied for statistical analysis.


RESULTS
Although the study was prematurely terminated owing to the high incidence of resorption of Chitra-HABg, 22 of the 24 subjects were followed-up for a minimum of 1 year. At the end of 1-year, excellent radiologic outcome was seen on the right side (autogenous graft) in all the cases, whereas 95% (21/22) of the cases had poor consolidation on the left side (Chitra-HABg). The clinical outcome was rated as good in 16/22 (73%) patients, fair in 5, and poor in only 1 patient, but this had no statistically significant association with the consolidation of the fusion mass.


CONCLUSIONS
This study clearly demonstrates that hydroxyapatite-bioactive glass ceramic composites (Chitra-HABg) has no role as stand-alone bone graft substitutes in posterolateral fusion of the lumbar spine, as the composite undergoes resorption without the formation of bridging callus.


METHODS
Level 1.
Acharya
Narayana K
NK
Department of Orthopaedics, Amrita Institute of Medical Sciences, Cochin, India. knacharya@hotmail.com
Kumar
Renjit J
RJ
Varma
Hari Krishna
HK
Menon
Venugopal K
VK
D018786:Bone Substitutes; D002146:Bony Callus / Q000000981:diagnostic imaging; D002516:Ceramics; D004185:Disability Evaluation; D017886:Durapatite; D005260:Female; D005500:Follow-Up Studies; D005898:Glass; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography; D013123:Spinal Fusion / Q000379:methods*; D013130:Spinal Stenosis / Q000000981:diagnostic imaging / Q000601:surgery; D013168:Spondylolisthesis / Q000000981:diagnostic imaging / Q000601:surgery*; D016896:Treatment Outcome
D018786:Bone Substitutes; D017886:Durapatite