The vertebrae, which stack up to create the spinal column, surround and protect the spinal cord and, in the lumbar spine, the nerve roots (called the cauda equina). The discs are located between each vertebra. Discs consist of a fibrous outer layer (annulus) surrounding a gelatinous center (nucleus). They allow motion between vertebrae, act as shock absorbers, and distribute the stress and strain placed on the spine.
When a disk weakens, the annulus may not be able to hold the nucleus in place and the disc may protrude into the spinal canal potentially irritating the spinal nerve roots. In advanced cases the nucleus may actually rupture (herniate) through the annulus and pinch the spinal nerve roots. This can cause a type of pain (radicular pain) which radiates down the thigh and/or leg. If the pressure on the spinal nerve roots continues, numbness or muscle weakness in the leg or foot may develop. Most patients with herniated discs do well with no surgical treatment; however a small percentage may require surgery. There are rare circumstances in which some patients require immediate surgery. These include cauda equina syndrome and/or progressive neurologic loss (increasing weakness). Symptoms of cauda equina syndrome may include change in bowel or bladder function, numbness or change in sensation in the area around the buttocks, genitalia, or thigh, and weakness or radiating numbness in the legs. People who develop symptoms of cauda equina syndrome should seek medical attention immediately.
Conservative Management: Most herniated discs get better with time, anti-inflammatory medications, and physical conditioning. Steroid injections may help relieve the pain and some of the inflammation around the nerve roots. If these attempts at conservative care do not relieve symptoms or if there is progressive neurological damage however; surgery may be necessary.
Microdiscectomy: is an operation to remove pressure on a nerve caused by a disc herniation. This surgery involves a vertical incision one to two inches in length along the midline of the back. The doctor uses a microscope to see and protect the nerve roots, and safely remove the portion of the disc that has herniated. Removing the fragment of disc material that is pressing on the nerve eliminates the pressure on that nerve.
The reason to do this surgery is to relieve the leg pain or weakness caused by the pressure on the nerve roots. The success rate of relieving leg pain is very high, approximately 90%. The success rate of relieving chronic back pain present prior to the surgery is much less predictable.
The length of the operation is typically short (60-90 minutes), but depends on the number of discs operated upon, whether or not previous surgery has been performed and the severity of the pressure on the nerve roots. Blood loss is minimal so no blood donations are necessary before the operation. Hospitalization is brief and most patients can go home the day of surgery. Some patients may need to stay overnight.
Recurrent Disc Herniation: The entire disc is not removed at the time of discectomy. Typically, only the portion of the disc that is pressing on the nerve is removed. It is possible for part of the remaining disc to push through the original defect (annular tear) causing leg pain to develop again. Recurrent herniation occurs in 3-10% of patients who undergo discectomy and can happen any time after surgery. This condition also happens with the same frequency to those patients who are treated conservatively.
Spinal Nerve Root Injury: Permanent spinal nerve root injury is extremely rare. It is not unusual, however to experience minor temporary tingling, numbness, weakness or pain which resolves over several weeks. All precautions will be taken but rarely, more serious nerve root injuries may occur, effecting walking, balance, bowel or bladder functions.
Dural Tear: Leakage of spinal fluid can occur due to a tear in the tissue (called the “dura”) holding the spinal fluid and containing the nerve roots. On rare occasions additional surgery may be needed.
Infection: Infection is always a post-operative risk and occurs in approximately 0.5-1% of lumbar microdiscectomy patients. Infections may be superficial or deep into the bone. You are given antibiotics before and after the surgery to help prevent this complication. Please follow the instructions for wound care to help prevent infection.
Other complications: Other possible complications include blood clots, pneumonia and complications related to the general anesthesia.
Adequate rehabilitation is crucial for a successful result. Many patients with spinal injuries have suffered from spinal pain for some time. This may result in considerable weakening of the spinal muscles due to lack of exercise, so you should return to the normal activities slowly.
The primary form of rehabilitation after microdiscectomy is an aggressive walking program. You should start immediately after discharge, walking more and more each day. In general, we recommend two to three episodes of exercise per day. The average patient should be walking 20 minutes twice a day by their first postoperative visit and 40 minutes twice a day by six weeks after surgery. Walk more if you are so inclined!
Patients routinely experience a dramatic reduction in their leg pain. If the nerve has been irritated for a long time before surgery, then a more gradual reduction of the leg pain is to be expected. As the nerve heals, you may experience tingling or a warm feeling. Numbness in the leg/foot experienced before surgery is often the symptom which takes the longest to resolve.
Back pain associated with the incision is largely improved within two to three weeks. Increased pain with prolonged sitting and driving is also expected.
At your first post-operative visit we will inspect your wound and remove any stitches as necessary.
Prescribed narcotic pain medication may cause some constipation. To help with this:
If you need a refill on your pain medication, please have your pharmacy fax the refill request to our office @833-472-3627and please allow up to 48 hours for the request to be processed. Refills on pain medication will not be filled after hours or on weekends or holidays. Be aware of how much pain medication you have, & obtain refills before you run out.
Avoid twisting your neck to the extremes, and avoid forced bending of your neck either forward or backward. Gentle range of motion of the neck is OK. Do not drive until you have received permission from your physician.
Dr. Amer Khalil is a fellowship trained & board certified neurosurgeon with specialty in artificial disc replacement and minimally invasive spine surgery. His clinical interests include cervical and lumbar spine surgery (eg, sciatica), complex deformity surgery and scoliosis, lateral access and minimally invasive surgical procedures, spine fractures and spinal cord injury, spinal tumors, spondylosis and spondylolisthesis. Dr. Khalil has special interest in innovative therapies and technologies to improve the health of patients.