Spinal Balance and Adjacent Segment Degeneration
Spinal balance is critical
Balance is absolutely critical in spine surgery. The delineation between good and excellent surgery may depend on how well the surgeon balances the spine during the reconstruction.
A spine which is decompensated or tilted forward, will require increased energy utilization by the various muscles which support the head, the neck, and the rest of the spine. A spine which is out of alignment and pitched forward will require various back, buttock, and leg muscles to “right the spine” during activities such as sitting and walking. This increased energy requirement may cause the muscles to become easily fatigued which may in fact cause pain. Reconstruction surgery which reduces the normal curvature of the spine of the lumbar spine (flatback syndrome) may in fact leave a patient more vulnerable for symptoms than prior to reconstruction.
Adjacent Segment Degeneration
The main concerns patient’s express about a spinal fusion are loss of motion and the possibility of adjacent segment degeneration.
The lumbar spine has a small range of motion, approximately 7 degrees, and the majority of movement in bending comes from the hips and hamstrings.
The discs act as shock absorbers between the vertebral bodies. When a disc is replaced with a boney fusion, the disc above a fusion (adjacent level) absorbs more of the wear and tear of daily activities. The key variable in minimizing degeneration of adjacent levels is alignment of the fusion.
The surgical options for spinal instability are Anterior Spinal Fusion, Posterior Spinal Fusion, or Anterior and Posterior Spinal Fusion. I believe an anterior release and interbody spinal fusion, followed by posterior instrumentation is the best way to realign the spine and create lumbar lordosis. The key to a long-term successful outcome is spinal alignment.
Choosing a surgeon
When choosing a surgeon for any sort of spinal reconstruction, it is absolutely critical that the question of balance be raised. Although various techniques may seem state-of-the-art or minimally invasive any technique which does not attempt to recreate normal spinal balance may have long lasting negative or adverse results on the patient’s spine health.