Abstract
Background: The major problem achieving lumbar spinal fusion is developing pseudarthrosis. At present the gold standard in achieving fusion is the use of autograft from pelvis or posterior elements of the spine. However the potential limitations of insuffient quantity and donor site morbidity have led to search for bone graft alternatives like DBM which contains osteinductive BMPs.
Aims & Methods: A Prospective Randomized Control trial comparing the effectiveness of demineralised Bone Matrix (DBM Putty)/autograft composite with autograft in lumbar spinal fusion.
35 patients were included in the trial; they were randomized to have DBM and autograft on one side, and autograft alone on other side to side. Patients were followed up with interval radiographs for total of 24mons. To date 20 patients have completed minimum 12mons follow up. The mineralization of fusion mass lateral to the instrumentation on each side was graded Absent, Mild (< 50%), Moderate (> 50%) or Complete fusion (100%). The assessment was made by two orthopaedic consultants and a musculoskeletal radiologist who were blinded to graft assignment.
Results: The sex distribution was 11:9 male to females with a mean age of 55.2 (21–87 years) and an average follow up of 18mons (12–24mons). Nine patients had single level fusion and the remainder had more than one level fusion. At 12 months on the side of DBM, 15% (6 of 20) had complete fusion, 80% (16 of 20) had moderate fusion, and 5% had no fusion mass. During the same period on the other side, 25% did not show any sign of fusion. There was no correlation with number of levels, age or sex.
Conclusions: Osteoinductive properties of DBM would appear to help in achieving early and higher union rates in lumbar spinal fusion. DBM reduces the amount of harvested autograft graft and also minimises the morbidity of donor site complications.
Correspondence should be addressed to: Mr N. J. Henderson, BASS, c/o BOA, The Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE.
