Laminectomy for Sciatica
Laminectomy, laminoplasty, and laminotomy may all relieve the pressure on lumbar nerves which is causing sciatica. The more extensive the removal of structural tissue, the more likely a patient is to require additional spinal fusion surgery, with microsurgery preferable for patients with fairly straightforward spinal stenosis in the lumbar spine. If significant canal stenosis is present at numerous levels then a laminotomy or small scale laminoplasty is unlikely to provide as extensive relief from sciatica as a laminectomy with fusion.
A laminotomy may be performed to provide the surgeon access to bulging or herniated disc material, or osteophytes, and can be carried out using minimally invasive surgical techniques. The laminotomy procedure leaves the majority of the back bone to stabilize the spine, unlike a laminectomy, and may be preferred in cases where stenosis exists at only one level as indicated by fairly specific sciatica symptoms. Laminoplasty is a type of back surgery where the laminae is scored on one side and opened like a door, with metal plates attached in order to maintain this position. The extra space allows the spinal canal to relax and relieves pressure on the spinal nerves and cord. Laminoplasty has the advantage of creating a reasonable amount of space for decompression purposes whilst maintaining the structure of the spine and reducing the need for fusion due to instability. Laminoplasty may be helpful for patients with spinal stenosis causing sciatica at one or more levels in the lumbar spine but may be dismissed in favor of a laminectomy with fusion if the patient exhibits signs of spinal instability or other complication.
Laminectomy with or without Fusion
Sciatica which involves stenosis at a number of intervertebral levels may be treated using a combination of a laminectomy, followed by a discectomy, or partial discectomy followed by a spinal fusion procedure. The laminectomy removes a portion of the back bone and can grant the surgeon excellent access to the material which is compressing the spinal nerves. This may be a bulging or herniated disc, fragments of bone or disc that have worked themselves loose, osteophyte growth, or calcified ligaments in the exterior spine putting pressure on the nerves as they exit the spine. Spondylolisthesis is another possible cause of sciatica, with the slightly offset vertebrae causing nerve compression. Back surgery to correct spondylolisthesis and stabilize the lumbar spine is likely to provide the most relief and will usually involve spinal fusion.
After the offending material has been removed the surgeon may perform spinal fusion in order to maintain, or restore, the intervertebral height at that section and reduce the risk of segmental motion. Discectomy, laminectomy, and fusion are more likely in cases where considerably osteophyte growth exists across a number of vertebral levels, or where multiple herniation and bulging is observed across a number of levels. Fusion may be in the form of an autograft, with bone taken from the patient’s hip and secured by rods and screws, or an allograft, where donor bone is utilized. Laminectomy is a major back surgery and requires the cutting of muscle and ligaments to reach the back bone.
There are possible complications surrounding the extent of structural tissue removed and its resulting effect on the stability of the spine. Patients need to be cautious about twisting and bending the spine during their recovery in order to prevent hardware failure or graft movement. The rigidity after spinal fusion can cause pressure to be deferred onto the adjacent segments and lead to fracture or other problems at those levels. Recovery from laminectomy can be prolonged and surgeons favour more minor procedures where they will be as helpful. Patients are usually advised against using NSAIDs after a fusion procedure as this can affect the formation of a solid union. Smoking is a major risk factor for pseudoarthrosis, with some surgeons unwilling to operate on those who have failed to quite smoking prior to the back surgery. Around 70-80% of patients with sciatica who undergo a lumbar laminectomy experience some degree of relief from their symptoms.