Lumbar spinal decompression
Compression of the nerve roots and narrowing of the lumbar spinal canal can be caused by the intervertebral disc, ligaments and rapid growth of bone (osteophytes). Compression of the nerve roots can cause pain in the legs (calves) when walking. It can also cause numbness and weakness in the legs while walking as well as bowel/bladder issues.
A posterior lumbar decompression surgery involves the removal of all the structures that are compressing the nerve root. This includes part of the lamina (laminotomy) or the whole lamina (laminectomy), ligaments, and new bone (osteophytes). The lamina is the bony portion of the vertebra that rests behind the spinal cord. The lamina must be removed to access the spinal cord and nerves. Lumbar decompression surgery is effective in relieving the leg pain but the weakness, numbness, and the pins and needles effect in the legs (if present) may take a few months to clear up. Occasionally, this sensation, may not resolve completely depending on the severity of the symptoms.
Lumbar spinal fusion
Arthritis and degeneration (wear and tear) of the spine leads to a loss of normal spinal alignment and instability (abnormal movement), both of which may cause back pain and compression of the nerves.
A lumbar spinal fusion involves inserting screws into the vertebrae. These screws are then connected by rods and bone grafts around the vertebrae. The aim of the surgery is to prevent movement between the involved vertebrae and to realign the spinal column. This will reduce the pain. The screws are rods are made of either titanium or stainless steel; both materials are tolerated by the body.
Depending on the symptoms, x-rays, and scans, the surgeon will decide whether you need a spinal decompression, a spinal fusion, or a combination of the two.
About the surgery
Anesthesia: The surgery is done under general anesthesia. During the procedure, the patient will be lying face down on the operating table.
Procedure: A 5-10 cm incision (cut) is made on the skin over the part of the spine that hurts. The muscle is disconnected from the underlying bone (laminae) and either a portion of the lamina (laminotomy) or the whole lamina (laminectomy) is removed along with the surrounding ligaments to access the nerve roots. The ligaments, intervertebral disc, and new bone (osteophytes) that are compressing the nerve roots are cut out. This procedure is called a spinal decompression. If the surgeon has decided to fuse the spine, screws are inserted into the vertebrae (spinal bones) which are then connected with rods. Through a bone graft, bone is taken from the pelvis and is then placed across the operated levels. This allows new bone to form (over 3-6 months) between the two adjacent vertebrae. In addition, bone graft and/or cages (spacers) may be placed between two vertebrae after the removal of the intervertebral disc. A drain tube removes the blood that accumulates at the surgical site. Dissolvable sutures are used to close the skin.
In the recovery room: After the surgery, you may feel some pain on the operated area when you wake up. Pain medications, antibiotics, and IV fluids will help you stay hydrated and stable. You may also receive a temporary urinary catheter to use the bathroom.
In the ward: After your surgery, you’ll be put on a liquid diet before slowly going back to a full, regular diet. You may only drink sips of fluids immediately after the surgery. You will be provided with medications to relieve your pain for 1-2 weeks. However, please remember to notify a nurse if you feel extreme pain! Additionally, the drain tube and catheter will be removed a day after the surgery. You will then be able to walk around with a support brace. Typically, you’ll stay in the hospital for 3-5 days, depending on your surgeon’s suggestions.
At home: Remember to stay active to speed up your recovery! Take short walks every day and slowly increase the distance. Please avoid heavy lifting, strenuous activity, and excessive movement of your neck. If you can, try to have someone to help you with your chores and errands for the first few weeks. The last thing you want to do is over-exert yourself!
Risks and potential complications
Keep in mind all surgical procedures come with a risk of complications. You should thoroughly talk about these risks with your surgeon before the procedure. Remember to list out any allergic reactions to anesthesia or other medicines to your surgeon and anesthetist. Other chronic illnesses related to your heart or lungs – such as hypertension, diabetes and asthma – should also be disclosed. Provide a list of all your current and past medications. Remember, unexpected complications such as stroke, heart attack, and pneumonia are not caused by surgical treatment and are generally rare. However, these rare complications may have serious consequences.
Surgical complications can include bleeding, infection, spinal fluid leak, injury to the veins and arteries near the spine, or injury to the nerve tissue or the protective layer surrounding it. Injury to the nerves may occur during surgery, resulting in paralysis of certain muscles in the legs and loss of sensations. Loss of bowel and bladder control can also occur due to nerve injury. An injury to the dura, the outermost layers of the nerves, can result in leakage of spinal fluid and may occasionally require a repeat surgery to control the leak. The insertion of the screws can potentially cause nerve injury resulting in weakness and abnormal sensations in the legs. Great care is taken to ensure the accurate placement of the screws, which includes the use of intraoperative fluoroscopy (x-rays).
Although antibiotics are given before and after surgery, there is a 1-5% chanceof wound infection. Superficial infections can be treated with antibiotics; deep infections may require a wound wash-out while under anesthesia. Having an infection immediately before your surgery in the chest, skin, and urinary tract regions may put you at a higher risk of post-operative spinal infection.
Please inform your surgeon of any of these infections to decrease the risk of post-operative infection!
Deep vein thrombosis (DVT: clotting of blood in your calf muscles) and pulmonary embolism (clot migrating to your lungs) are uncommon after an elective spine surgery, particularly when you are out of bed and walking within 24 hours after surgery. We use calf compressors and TED stockings to prevent the clotting of blood in legs; we do not routinely use medications. However, if you have had an episode of DVT in the past, let your surgeon know.
In rare cases, solid fusion may not occur. When this happens, further surgery to re-fuse the spine may be necessary. Non-fusion (non-union) rates are higher for patients who have had spinal surgery in the past, as well as smokers, patients who undergo multiple level fusion surgery, and patients who have undergone radiation for cancer. Not all patients who have a non-union will need to have another fusion procedure. As long as the joint is stable and the symptoms are better, further surgery is not necessary. Conversely, there is a risk of having a successful fusion but without relieving the nerve pain.
Notify your surgeon at once if you notice the following after surgery
- Extreme bleeding
- Redness or discharge from the wound
- Continuous headache
- Weakness or numbness in the arms and legs
- Difficulty urinating
Talk to your surgeon
This is a concise overview and does not include all the known facts about your condition and the surgery. If you have any questions, make sure to seek any clarifications from your surgeon and his team. It is important for you to attain a clear understanding of your condition and the risks, benefits, and limitations of the surgical procedure before taking action.