Natural hydroxyapatite as a bone graft extender for posterolateral spine arthrodesis.

PURPOSE: The aim of this retrospective analysis of spinal fusion, was to document the clinical, functional, and radiological outcomes with a local bone graft plus the highly osteoconductive hydroxyapatite, bio-derived Orthoss®, with or without bone marrow aspirate.
METHODS: Forty seven patients submitted to spinal posterolateral fusion were operated for four major indications: scoliosis in young patients (11), degenerative spine (18), lumbosacral transitional anomalies in young adults (14), and spine trauma (four). Sixteen patients had more than four levels fused. In addition to spinal decompression and instrumented fusion, autologous bone grafts from the excised lamina were augmented with Orthoss® granules in a 1:1 ratio. In addition iliac crest bone marrow aspirate was used in 70 % of the patients. The results were assessed clinically in terms of pain, and return to school or professional activities were checked at three, six, and 12 months following surgery with a mean follow-up of 20 months. In scoliotic patients, correction of the major angle was evaluated from one to four years after surgery.
RESULTS: Pain persistence was reported only in four cases, after three months after surgery. A functional recovery was noted in almost all patients groups within these three months. Progressive bone formation with evidence of bone fusion masses were already observed at six months. No fusion failure was observed.
CONCLUSIONS: Local bone enhanced by an osteoconductive long-term stable scaffold, used with and without bone marrow aspirate, led to successful fusion in all patients by six months while functional recovery was reported already within three to six months.