In March 2008 I had my fourth lumbar revision spine fusion for spondylolisthesis L2-L5. NSpine instrumentation (Synthes company) was used. Results were good for one year and pain returned. Diagnosis was collapse of L1-2 plus broken NSpine rods and one screw at L5. There is no explanation for the hardware failure and I understand this is quite unusual in absence of trauma. As a result I had fifth fusion surgery in May 2010. Has anyone had a similiar problem with NSpine instrumentation?