Jonathan N. Grauer

Indications, techniques, and outcomes of posterior surgery for chronic low back pain

This article summarizes a number of issues surrounding the diagnosis, indications, and techniques of posterior lumbar spine surgery for chronic low back pain. It would not be entirely unjustified for a spine surgeon to adhere to a totally avoidant approach to chronic low back pain, rationalized by a reasonably legitimate nihilism regarding the presently available means of diagnosing and surgically managing low back pain [64]. Judging by the number of lumbar fusions performed in North America and the tremendous intellectual and financial investment currently being made in technologies to enhance spinal fusion, such an approach is evidently not achieving wide-spread acceptance on this continent. A rationale approach is therefore required for the many low back pain sufferers with degenerative disk disease who arrive in the office having exhausted almost every imaginable form of nonoperative therapy. Every effort should be made to establish a pathoanatomic etiology of the back pain with a combination of diagnostic modalities. Surgical intervention should be approached cautiously and only after extensive dialog with the patient to establish realistic goals and expectations. Posteriorly performed interbody fusion procedures may provide a high fusion rate and satisfactory clinical outcomes for this challenging problem, although further research is necessary to determine more conclusively the role of surgery and the relative effectiveness of the various arthrodesis techniques.

Bone Graft Alternatives for Spinal Fusion

Bone grafting to achieve fusion is frequently performed in spinal surgery. Autograft is the gold standard bone graft material. However, due to limitations of supply and morbidity associated with the harvest of autograft, alternatives are being considered. Osteoconductive matrices, such as allograft, calcium or ceramic preparations are one such class of potential bone graft alternatives, but generally they lack osteoinductive properties. Recent attention has focused on osteoinductive materials such as demineralised bone matrix, recombinant bone morphogenetic proteins and bone marrow aspirates or blood product concentrates. These products may be combined with osteoconductive carriers and are clearly finding a place in the clinical arena.

Anterior Corpectomy with Fixation, Thoracic

Because of the additional stability provided by the rib cage and the coronal orientation of their facet joints, the thoracic vertebrae are less susceptible to traumatic injury than the cervical or lumbar regions of the spine. While the majority of thoracic fractures may be adequately managed with a period of immobilization and early ambulation, anterior thoracic procedures performed through a thoracotomy may be preferable in certain cases because they allow for a thorough decompression of the neural elements and the placement of a load-sharing interbody implant within the vertebral column. In recent years, anterior instrumentation systems have also been developed that may confer even greater stability to the disrupted segment. This surgical approach is best suited for patients who demonstrate severe canal compromise or focal kyphosis; however, stand-alone anterior constructs may not be appropriate for fracture–dislocations or ligamentous injuries that may require supplementary posterior fixation.