Spinal stenosis results in a symmetric compression on the spinal nerves due to degeneration and overgrowth of the joints, ligaments, and bone spurs. Surgery to treat spinal stenosis often requires more extensive decompression than a simple microdiscectomy and is known as a Laminectomy. This procedure involves “unroofing” the spinal canal by removing the bone, known as the lamina, and enlarged ligaments along the back of the spine. The arthritic facet joints are also shaved down to provide more room for the exiting spinal nerves.
Compared to a Microdiscectomy, patients typically experience an increased degree of post-operative discomfort due to the greater extent of muscle dissection and the larger skin incision. This is required to expose both sides of the spine, as opposed to a microdiscectomy that typically requires exposure of only one side. On average, patients are discharged from the hospital one to two days following surgery. Activities are limited to walking for the first several weeks following the operation. Physical therapy is often useful, initially involving stretching and range of motion exercises followed by endurance and strength training.
Cervical Laminectomy and Foraminotomy
Degenerative changes of the cervical spine can produce compression of a spinal nerve, causing a radiculopathy — pain, sensory changes, and weakness in a single extremity. Compression of the spinal cord can lead to more profound dysfunction — known as a myelopathy — that produces sensory changes and weakness in both arms and/or legs, loss of coordination, or incontinence of bowel/bladder function. Nonoperative management may be attempted but is less likely to produce significant relief, particularly if the spinal cord is affected.
When conservative maneuvers fail or the spinal cord is at risk of permanent injury, surgical intervention is often the treatment of choice. The procedure is intended to release the spinal cord and nerves by removal of the degenerative bones and ligaments. If the majority of compression is located along the back of the spine and a normal spinal alignment is maintained, the procedure of choice is known as a cervical laminectomy and foraminotomy. Other options include Anterior Cervical Discectomy and Fusion / Fixation.
Cervical laminectomy and foraminotomy is performed under general anesthesia. An incision is made down the middle of the neck overlying the areas of pathology. The muscles are dissected to expose the back of the cervical spine. The cervical lamina are removed (the laminectomy) to release the spinal cord. Nerves are released by shaving a portion of the facet joint (the foraminotomy) that is compressing the nerve. Once the decompression is complete, the muscles are re-approximated and the incision is closed in multiple layers with absorbable sutures.
Course of Treatment
Patients are usually admitted for two or three days following surgery. Post-operative pain is usually controlled with oral medications. Patients are encouraged to ambulate as soon as possible, often on the day of surgery. Consultation with a physical therapist and rehabilitation specialists during hospitalization is usually reserved for patients demonstrating significant neurologic dysfunction. Following discharge, patients are encouraged to increase their activities as they are able to tolerate. Physical therapy focused on the neck is not instituted until the initial follow-up visit, usually four to six weeks after surgery.
Instability of the spine as a result of degenerative changes can lead to a reactionary growth of associated ligaments and joints, nature’s attempt to restore stability. Unfortunately, these compensatory mechanisms compromise the normal space occupied by the spinal nerves. Compression of the nerves as a result of these compensatory changes can lead to the syndrome known as neurogenic claudication — activity-related pain in the lower back and legs that is relieved with rest. Nonoperative maneuvers typically produce temporary relief. Definitive correction often requires removal of the compressing elements through a procedure known as a laminectomy.
The procedure is performed under general anesthesia. A midline incision in the lower back is centered over the affected area. Dissection through the back muscles provides access to the spine. The portion of the vertebra known as the lamina is removed along with any thickened ligaments to release the nerves traveling down the center of the spinal canal. Individual nerves are released as they exit the spinal canal by shaving a portion of the degenerative facet joint. The soft tissues are then closed in multiple layers with absorbable sutures.
Course of Treatment
Patients are usually admitted for one to three days following surgery. Ambulation is encouraged on the day following surgery, and patients are allowed to increase their activity level as tolerated. If necessary, physical therapy for lower back strengthening and range of motion is usually started following the first follow-up visit, four to six weeks after surgery.