Introduction: Lumbar fusion has been used to treat patients with a variety of conditions that include trauma, tumor, infection, instability and spondylolisthesis. Bone grafting can be used alone or as an adjunct to instrumentation, and there is debate regarding the selection of graft product. Although autologus iliac crest graft is associated with a high rate of fusion, it may be argued that it will increase the length of procedure and blood loss and may increase short and long term complications at the donor site. The use of allograft has eliminated this subgroup of complications, but some question remains about the long term outcome and if radiographic fusion is associated with good clinical outcome.
Methods: A retrospective review of 500 cases using instrumented lumbar fusion and allograft bone was performed. Clinical outcome was examined during the initial postoperative period and followed over 3 months postoperative and up to 2 years.
Results: In the early postoperative period, younger patients had more postoperative pain than the elderly however long term outcome is similar. There was no difference in the rate of intraoperative complications between first time surgical patients and redo surgery patients. There is no correlation between rate of fusion and clinical outcome. There was no clinical difference between the fusion for smokers versus non-smokers. Good decortication of transverse processes and facet joints and removal of all soft tissue plays a significant role in the fusion rate. Patients with congenital pars defect and anterolisthesis had better clinical outcome than patients with mechanical lower back pain and degenerative disc disease.
Conclusions: Clinical outcome after lumbar fusion is less influenced by rate of radiographic fusion and more likely determined by indication for the surgery and patient expectations. Fusion with allograft and using external bone stimulator in high risk patients is an alternative to autograft.
Patient Care: Establishing strict criteria and indications for lumbar fusion and explaining intraoperative pitfalls that may help residents, fellows and young neurosurgeons
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of clinical outcome for lumbar fusion and stabilization in different age groups using allograft 2) Discuss, in small groups, patient selection and indication criteria for surgery and the dominant factors for good clinical outcomes 3) Identify and emphasize technical points for stabilization and fusion which decrease operative time and blood loss and improve fusion rate