Lumbar Spine Surgery: Lumbar Fusion

We are offering new hope for patients suffering from mechanical back and/or leg pain secondary to spinal cord or nerve root compression through lumbar spinal instrumentation, or LSI. Patients most commonly present with a combination of spinal stenosis (narrowing) and spondylolisthesis (slippage) of the lumbar vertebra causing nerve compression. Spinal stenosis is most often seen in patients over 50 and is secondary to degenerative changes that occur in the spine as a result of aging. Spondylolisthesis most often occurs as a result of degenerative changes, but can likewise be seen secondary to trauma to the lumbar spine, or in those patients who are post-laminectomy. The levels most commonly involved are L4-5 and/or LS-S1. Risk factors for these changes to the spinal column include prior spinal or abdominal surgery, obesity, prior trauma or repetitive injury, and cigarette smoking. 

Patients with degenerative spondylolisthesis typically present with a long and slowly progressive history of low-back and diffuse bilateral leg pain that increases with ambulation (walking). Patients will commonly say that the distance they are able to walk has become shorter and shorter If the condition is left untreated, it may simply become too painful for the patient to walk, and they may then resort to the use of a wheelchair or other assistive device.  

Patients are considered for surgery when efforts at conservative treatment have failed to relieve symptoms. Patients, who exhibit X-ray evidence of spondylolisthesis or bone slippage and movement, are those most likely to benefit from LSI. Outcome following LSI is generally better and more rapid if the patient is diagnosed early, and surgical intervention is accomplished prior to muscle atrophy and an inability to ambulate secondary to neural compression. LSI is intended to decompress the area of stenosis as well as to prevent any progression in the degree of spondylolisthesis. Generous foraminotomies are performed in order to decompress the neural foramina (the area where the nerve exits the spine). Only rarely is it necessary to realign the spine or reduce the slippage in non-traumatic spondylolisthesis.

LSI was once thought to be too traumatic for the older patient. Concerns with cardiac disease, pre-existing medical conditions or blood pressure instability in a patient undergoing a lengthy and complex operative procedure often-precluded consideration of surgery in the older patient. Our neurosurgeons can perform this surgery in less than two hours and with minimal blood loss. Natural bony fusion can only occur once the spine is stabilized. Fusion rates have been shown to be excellent with the use of pedicle screws for stabilization. Patients now ambulate the same day as surgery, so the incidence of complications associated with immobility is greatly reduced.

As a result of decreased operative time, early post-op ambulation and adequate pain control, the length of hospital stay for patients undergoing lumbar spinal instrumentation has been decreased. This reduction in hospital stay, combined with the low incidence of postoperative complications, has resulted in increased patient satisfaction.

We are currently using pedicle screw fixation with rods and crosslinks and lateral bone fusion (See Picture). The average length of hospital stay is 4 to 5 days, with 90 percent of the patients then returning to their homes. Post-op complications were rare, but will be reviewed prior to surgery. Most patients have significant improvement in preoperative weakness at their one-month post-op visit.

Overall, LSI generally is a safe and effective operation that is feasible for nearly all patients diagnosed with symptomatic spondylolisthesis who are refractory to conservative management.