Lumbar Decompression and Fusion Surgery
Normal Lumbar Spine
Compression of the nerve roots and narrowing of the lumbar spinal canal can be caused by the intervertebral disc, ligaments and overgrowth of bone (osteophytes). Compression of the nerve roots can lead to pain in the legs (calves) on walking, numbness and weakness in the legs on walking and occasionally bowel and bladder complaints.
A posterior lumbar decompression surgery involves the removal of all the structures - part of the lamina (laminotomy) or the whole lamina (laminectomy), ligaments and new bone (osteophytes) that are compressing the nerve roots. The lamina is the bony portion of the vertebra that lies behind the spinal cord and its removal is necessary to access the spinal cord and nerves. Lumbar decompression surgery is effective in relieving the leg pain but the weakness, numbness and pins and needles in the legs (if present) may take a few months to resolve and occasionally may not resolve completely, depending on the duration of symptoms.
Lumbar spinal fusion
After lumbar decompression
- View from the back
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 which are then connected by rods and the placement of bone graft around the vertebrae. The aim of the surgery is to prevent movement between the involved vertebrae and realign the spinal column so as to reduce the pain. The screws are rods are made of either titanium or stainless steel and are well tolerated by the body.
Depending on the symptoms, xray's and scans, the surgeon will decide whether you need a spinal decompression, a spinal fusion or a combination of the two.
About the surgery
After lumbar decompression
- view from the back
- Anaesthesia: The surgery is performed under a general anaesthetic, with the patient lying face down on an operating table.
- Procedure: A 5-10 cm incision (cut) is made on the skin over the affected area of the spine. The muscle is detached 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 excised. 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. Bone (graft) taken from the pelvis is placed across the operated levels are 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 removal of the intervertebral disc. A drain tube removes the blood that collects at the surgical site. Dissolvable sutures are used to close the skin.
After surgery
One level lumbar
fusion - front view
- In the recovery room: Following surgery, you will be transferred to the recovery room and may feel some pain at the operated site when you wake up. You will be given pain medications, antibiotics, intravenous fluids to keep you hydrated and a urinary catheter will empty your bladder. When you are comfortable you will be transferred to your room.
- In the ward: You will be allowed to drink sips of fluids after surgery and gradually progress to a full diet. Medications will be provided to reduce your pain after surgery and at home for the first 1-2 weeks. However, if you have excessive pain while you are in the hospital, the attending nurses should be informed. The day after surgery, the drain tube and the urinary catheter will be removed and you will be encouraged to walk wearing a brace to support your spine. You will stay in the hospital for 3-5 days and your surgeon will decide when you can go home.
- At home: Once you are at home, it is important to stay active and take short walks at regular intervals to help reduce pain and hasten your recovery. Gradually increase the distance you walk each day but avoid strenuous activities, heavy lifting and twisting. You may require some help with chores and errands for the first few weeks and it is advisable to have someone to help with these activities.
Risks and potential complications
-
One level lumbar
fusion - side view -
Two level lumbar
fusion - front view
All surgical procedures are associated with a risk of complications and all risks should be discussed with your surgeon. Allergic reaction to the anaesthetic or other medications and unforeseen complications such as pneumonia, stroke or heart attack are not caused by the surgical treatment and although rare it may have serious consequences. Please let your surgeon and anaesthetist know if you are allergic to medications and if you have any medical problems (relating to your heart, lungs, diabetes or increased blood pressure) and provide a list of your current and past medications.
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 its surrounding protective layer. 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 covering layers of the nerves (dura) 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 including the use of intra-operative fluoroscopy (x-rays).
Although antibiotics are given before and after surgery, there is a 1-5% incidence of wound infection. Superficial infections can be treated with antibiotics, while deep infections may require a wound wash-out under anaesthesia. If you have had an infection in any other region (urinary bladder, chest and skin) immediately prior to surgery, you may be at a higher risk of post-operative infection in the spine, so let your surgeon know.
Two level lumbar fusion
Venous thrombosis (DVT: clotting of blood in your calf muscles) and pulmonary embolism 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.
Occasionally a solid fusion is not obtained (nonunion) and further surgery to re-fuse the spine may be necessary. Nonunion rates are higher for patients who have had prior spinal surgery, smokers, patients who undergo multiple level fusion surgery, and patients who have undergone radiation for cancer. Not all patients who have a nonunion will need to have another fusion procedure. As long as the joint is stable, and the patient's symptoms are better, more surgery is not necessary. In addition, there is a risk of achieving a successful fusion, without relieving the pain.
-
Three level lumbar
fusion - front view -
Three level lumbar
fusion - side view
- Excessive bleeding
- Redness or discharge from the wound
- Fever
- Persistent headache
- Weakness or numbness in the arms and legs
- Difficulty in passing urine
Notify your surgeon at once if you notice the following after surgery
Talk to your surgeon
This is a brief overview and does not contain all the known facts about your condition and the treatment options. Feel free to seek any clarifications from your surgeon and his team. It is important for you to obtain a clear understanding of your condition and the risks, benefits and limitations of the surgical procedure before proceeding.
