The effect of ketoprophen on lumbar spinal fusion healing in a rabbit model. Laboratory investigation

OBJECT: Several reports have shown that nonsteroidal antiinflammatory drugs (NSAIDs) have an inhibitory effect in osteogenesis and reduce heterotopic ossification in humans. A deleterious effect of NSAIDs in posterolateral intertransverse process fusion has also been suggested. The authors used a validated rabbit model to try to determine the influence of the NSAID ketoprophen on the fusion rate in lumbar spinal arthrodesis. METHODS: Thirty New Zealand male rabbits underwent posterolateral (intertransverse process) bilateral spinal fusions at a single level, using autologous bone graft obtained from both iliac crests. The animals were randomized after the operation, so that 15 rabbits received ketoprophen as a postoperative analgesic and the other 15 received the postoperative analgesic tramadol. The animals were killed 8 weeks after surgery, and fusion status was determined by inspection, palpation, anteroposterior radiographs, and histological analysis. RESULTS: A solid fusion was obtained in eight rabbits (53%), and pseudarthrosis in seven rabbits (47%) in each group. CONCLUSIONS: These findings suggest that the use of ketoprophen after intertransverse spinal fusion at a single level does not decrease the fusion rate, compared with tramadol.