Spinal fusion, also called spondylodesis, is a neurosurgical or orthopedic surgical technique that joins two or more vertebrae. This procedure can be performed at any level in the spine (cervical, thoracic, or lumbar) and prevents any movement between the fused vertebrae. There are many types of spinal fusion and each technique involves using bone grafting—either from the patient (autograft), donor (allograft), or artificial bone substitutes—to help the bones heal together. Additional hardware (screws, plates, or cages) is often used to hold the bones in place while the graft fuses the two vertebrae together.

Spinal fusion is most commonly performed to relieve the pain and pressure on the spinal cord that results when a disc (cartilage between two vertebrae) wears out (degenerative disc disease). Other common pathological conditions that are treated by spinal fusion include spinal stenosis, spondylolisthesis, spondylosis, spinal fractures, scoliosis, and kyphosis.

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