Surgery For Spinal Stenosis
A one inch (or longer for extensive stenosis) incision is made in the middle of the back over the effected region of the spine. The muscles over the bone are moved aside until the laminae are visualized. The correct level is then identified again. With the use of a microscope and specialized tools, the laminae are removed and the nerves are decompressed (released so that they are no longer pinched). All the unnecessary bone spurs and thickened ligaments that compress the nerves are also removed. This portion of the case is called a laminectomy and is all that is required in the majority of cases of spinal stenosis. This is a very safe operation which is usually performed in a short period of time (30 minutes to 120 minutes depending of the extent of stenosis) without any significant complications (I will discuss individual complications with you). The overwhelming majority of patients with spinal stenosis experience immediate relief of their symptoms after surgery and are very satisfied.
Laminectomy with Fusion
Patients with back pain due to spondylolisthesis (abnormally slippage between bones), scoliosis (curvature of the spine) or spondylosis (severe arthritis of the spine) may require a fusion with or without the placement of screws and rods. While this is also a very safe procedure, it does add more operative time and is generally associated with a slightly longer recovery and post- operative pain compared to laminectomy alone. After this procedure, most people go home in 3-4 days.
Figure: Lateral radiograph (Xray) demonstrating a spondylolisthesis (slipping of the bones) at L4-5
Figure: X-rays of the same patient after he underwent a L4-5 laminectomy & fusion to stabilize the slip at L4-5. The screws and rods prevent the abnormal motion (translation) between the L4 and L5 bones thus relieving the pain.
This is a “minimally invasive” procedure that relieves the pressure off the nerves with the insertion of a metallic device in between the spinous processes of the vertebrae. The insertion of this device distracts the two bones which increases the space between the two vertebrae, thus creating more room for the nerves that are in between the two bones. There is no bone removal in this procedure and thus there is less postoperative pain than a laminectomy. There is also no “fusion” with this procedure. Most patients go home the same day (outpatient surgery) with this procedure; however, I give patients the option of staying in the hospital (usually overnight) depending on their preference. For certain patients, this procedure can be performed without general anesthesia (with the patient in a “twilight” but without a “breathing tube”).
Figure: The MRI on the top demonstrates spinal stenosis at L4-5. This patient failed nonoperative treatment and underwent the X-STOP procedure. The radiograph on the bottom demonstrates the postoperative position of the X-STOP implant. The patient had complete relief of his lower extremity symptoms after the 15 minute X-STOP procedure and went home the following day.
ALIF (Anterior Lumbar Interbody Fusion)
This surgery is typically performed at the L5-S1 level. A 3-inch incision is placed on the very lower part of the abdomen (above the front part of the pelvic bone). The abdominal contents are moved to the side and the the L5-S1 disc is exposed. The degenerative intervertebral disc is removed and a plastic spacer (packed with bone graft, BMP, and/or allograft) is inserted between the vertebral bodies to distract and realign the adjacent vertebrae and relieve the pressure on the nerves. This procedure can take 60 to 90 minutes depending on degeneration and deformity. Most patients stay in the hospital for 2-3 days and then go home. For patients with an isolated L5-S1 problem this is the best procedure because: it provides the most biomechanical stability, does not require any dissection (cutting) of the back muscles and thus causes less pain than a posterior approach. Depending on the extent of the problem, posterior screws may also need to be placed to achieve stabilization. If this is the case, these screws are placed in a minimally invasive fashion through 1-cm incisions on the back without the traditional muscle cutting technique. Whether or not a patient needs screws is dependent on an individual’s bone quality, pathology and other medical conditions. It is generally discussed preoperatively.
Direct Lateral Approach (XLIF/S-LIFT)
This is also a “minimally invasive” procedure for lumbar spinal stenosis. This technique is utilized when the stenosis is caused by or associated with scoliosis, instability (spondylolisthesis) or severe disc degeneration. A 1-inch incision is placed on the side, the intervertebral disc is removed and a plastic spacer is inserted between the vertebral bodies to distract the adjacent vertebrae and relieve the pressure on the nerves.
This procedure can take 30 to 120 minutes depending on the extent of spinal stenosis. Most patients stay overnight and go home the following day. For patients with severe scoliosis, this is also an excellent method to achieve deformity correction without the extensive pain, operative time and blood loss associated with traditional scoliosis surgery. For patients with severe scoliosis and others with osteoporotic bone, screws may also need to be placed to achieve absolute stabilization. Even so, these screws are placed in a minimally invasive fashion through 1-cm incisions on the back. Whether or not a patient needs screws is dependent on an individual’s bone quality, pathology and other medical conditions. It is generally discussed preoperatively.
The patient in the above radiograph is a 62 year old female who underwent a posterior fusion 12 years ago. She developed stenosis with a degenerative disc at the level above the fusion. Note the flattened disc space on the radiograph on the left; note how the XLIF spacer restored the disc height on the radiograph on the right. She underwent the XLIF procedure for this problem. The surgery took 30 minutes and she went home the next day with a minimal amount of “soreness” at the incision site. She had immediate of her leg pain, numbness and tingling.
This 72 year old woman underwent a minimally invasive fusion (utilizing the XLIF procedure) for lumbar spinal stenosis and scoliosis. She had one small incision on the side for the XLIF procedure and several very small incisions on the back for each screw. She was in the hospital for 4 days before going home (XLIF on Monday and the screws on Wednesday before being discharged on Friday). She lost a minimal amount of blood and did NOT need a blood transfusion. She was walking independently the day after each procedure. The radiograph on the left shows her scoliosis before the surgery and the radiograph on the right demonstrates her curve after surgery.
What happens after the surgery?
Patients are allowed to get out of bed and walk independently within a couple of hours of the operation. The overwhelming majority of patients experience significant, if not complete relief of the leg pain, numbness, tingling, etc. There is some pain at the incision site but it is generally well controlled with pain medication. Patients with a X-STOP or an XLIF usually go home the next day. Patients undergoing a laminectomy alone go home in 1-3 days while those with a laminectomy and open posterior fusion go home in 2-4 days. All patients are able to walk on their own and are independent in their activities of daily living (eating, drinking, personal hygiene, etc) when they go home.
Most patients are off all pain medications within a few days to a few weeks depending on their specific procedure. Within a few days after surgery, patients are allowed to resume all activities without restrictions (with common sense being the guiding principle); however, we also give each patient specific written instructions on the level of activity. There are individual exceptions to this and are discussed on an individual basis.