Clinical experience with the use of a spherical bioactive glass putty for cervical and lumbar interbody fusion

A retrospective clinical case series study was conducted to evaluate the use of a novel, spherical bioactive glass bone graft (BioSphere Putty) as a graft material for cervical and lumbar interbody fusion.

Data was collected from a single surgeon using BioSphere Putty along with standardized hardware in anterior cervical decompression and fusion (ACDF), transforaminal lumbar interbody fusion (TLIF), and anterior lumbar interbody fusion (ALIF) surgical procedures. BioSphere Putty was used in combination with cancellous allograft (ACDF and ALIF) or in combination with autograft (TLIF). Clinical outcomes were assessed at 1- and 2-year using radiographic imaging and the visual analog pain scale (VAS). VAS scores at the 1- and 2-year follow-up periods were statistically compared to pre-operative scoring. Successful clinical outcomes were determined by a combination of the presence of a complete radiographic fusion and a decrease in VAS at 1-year and 1- and 2-year follow-up periods.

The retrospective review of the patient data identified 248 cases that had either 1- or 1- & 2-year follow-up. This consisted of 115 ACDF procedures and 133 lumbar fusion procedures. Lumbar fusion cases were further sub-grouped with 103 patients undergoing TLIF procedures and 30 patients undergoing ALIF procedures. The global results for the series as a whole showed clinical outcomes comparative to other advanced biologic bone grafts. Radiographically all patients demonstrated fusion (100% fusion rate) and there were no clinical adverse events, infections, or graft-related complications in any of the patients in the series. One-year VAS scores were consistent with historical norms and demonstrated significant decreases in pre-operative pain for both ACDF patients (78% decrease) and lumbar patients (66% decrease TLIF/ALIF) (t test, P<0.05). By 2 years, VAS scores continued to drop with significant decreases for the ACDF patients (96%), TLIF patients (82%), and ALIF patients (80%) (t test, P<0.05). VAS scores were also assessed for each individual patient. The data showed a VAS score decrease from pre-operative levels in 93% of the ACDF patients and 89% of the lumbar patients. Combined with the 100% radiographic fusion rate in all patients, this resulted in a in a clinical success rate of 93% for the ACDF patients and 89% for the lumbar patients.

The results of this clinical case series demonstrated that BioSphere Putty is a clinically effective and versatile synthetic bone graft material in the spine.