Lumbar Disc Replacement

Surgery :: Anterior lumbar interbody fusion :: Anterior Cervical Decompression Fusion
Posterior Cervical Spine Surgery :: Spinal Deformity Surgery :: Lumbar Decompression and Fusion
Lumbar Discectomy :: Surgical Risks :: FAQ

Lumbar Disc Replacement

What is disc degeneration?

The inner portion of the intervertebral disc, the nucleus pulposus, is a soft jelly-like substance that holds water and is well hydrated in the normal state. This well-hydrated nucleus provides visco-elasticity to the disc and enables it to act like a shock absorber. Due to a variety of causes, the nucleus pulposus can undergo degeneration, loses its ability to hold water and becomes stiff.

The stiff, degenerated disc is unable to provide the shock-absorber action to the disc and the disc reduces in height (like a flat tyre). This places abnormal strain on the surrounding annulus fibrosis and eventually results in damage to the annulus. The degenerated disc can lead to instability and loss of the ability of the spine to sustain normal loads. This can be a cause of low back pain.

What does disc replacement do to improve the situation?

The aim of a disc-replacement surgery is to remove the degenerated disc and restore the normal function and movement of the spine using a prosthesis, thereby reducing the back pain.

The complete removal of the degenerated disc removes the pain generator and the spine is reconstructed using a three-piece prosthesis that restores the disc height, opens up the neural foramen and restores the facet joints to their physiological position. The three-piece prosthesis consists of two cobalt-chromium-molybdenum plates spray-coated with titanium that are attached to the vertebrae by a keel. A polyethylene (plastic) core is located between the two metal plates and allows for spinal mobility.

About the surgery

Anaesthesia: The surgery is usually performed under a general anaesthetic with the patient lying on the back.

Procedure: The surgeon makes a 7-10 cm incision in the skin over the front of the abdomen. The intestines are contained and the covering peritoneum are gently moved to one side and the spine is exposed from the front. Some of the large arteries and veins are also retracted to visualize the spine. The diseased disc is removed completely and the bony ends of the vertebrae on either side are prepared for implantation of the prosthesis. A cut is made in the vertebrae to receive the keel of the prosthesis. The two metal plates of the prosthesis are inserted, followed by the polyethylene (plastic) core. The incision is closed with dissolvable sutures and a drain tube removes the blood that collects at the surgical site. The procedure is expected to take approximately 3hrs in theatre for a single level replacement. Time spent in the Recovery unit can be added on to that ( approx. 1-2hrs) before being transferred back to your room on the ward.

Skin sutures: For initial spinal surgery you will have dissolving sutures, which will dissolve as your wound heals and do not need to be removed. However, the tip of the suture on either end of the incision will need to be trimmed on your first visit to the surgeon's office 7-10 days after surgery. (For those who may have had more than one operation at the same site, you will likely be given either staples or sutures that will need removal at this postoperative visit)

After surgery

Following surgery, you will be transferred to the recovery room and may feel some pain at the operated site when you wake up. A patient controlled analgesia (PCA) pump will be provided which releases a small dose of pain medication every time you press the button, thereby putting you in control of your pain. You will be given intravenous fluids to keep you hydrated and a urinary catheter will empty your bladder. When the medical staff in the recovery room are confident that you are comfortable, you will be transferred to your room.

In the ward: Since the abdomen was opened during surgery, it is better to avoid any oral fluids or food for the first 24 hours. On the day after surgery, the drain tube, urinary catheter and pain pump 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.

Pain relief: Although we expect that you will be in pain or discomfort, we recommend that you take regular pain relief following surgery. Medications will be provided to reduce your pain after surgery and at home for the first 2 weeks or so. If pain persist please seek advice from your General Practitioner or contact Spine Service.

Results after surgery

Eighty to eighty-five per cent of patients have a good outcome after a lumbar disc surgery. While there is considerable relief of the leg pain after surgery, the pins and needles, numbness and weakness in the legs may take 3-6 months to resolve, depending on the duration and severity of nerve compression. If the compression has occurred for a long period, complete resolution of the abnormal sensations and weakness may not occur. There is also a 5-10% incidence of recurrent disc herniation at the same level after surgery.

Possible Complications

All surgical procedures are associated with a risk of complications and all risks should be discussed with your surgeon. The risks may be associated with the anaesthesia given or the surgical procedure per se. Surgical complications can include bleeding, infection, spinal fluid leak, injury to the veins and arteries near the spine or injury to the spine's nerve tissue or its surrounding protective layer

Injury to the spinal cord or the nerves may occur during surgery and can result in complete paralysis of all four limbs or paralysis of certain muscles in the arms or legs, with loss of normal sensation. Loss of bowel and bladder control can also occur following injury to the nerves. An injury to the covering layers of the nerves (dura) can result in a leak of spinal fluid and this may occasionally require a repeat surgery. 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 mild 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.

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.

There is a major risk that is unique to the Anterior approach. The procedure is performed in close proximity to the large blood vessels that go to the legs. Damage to these large blood vessels may result in excessive blood loss. Quoted rates in the medical literature put this risk at 1% to 15%.

For males, another risk unique to this approach is that approaching the L5-S1 (lumbar segment 5 and sacral segment 1) disc space from the front has a risk of creating a condition known as retrograde ejaculation. There are very small nerves directly over the disc interspace that control a valve that causes the ejaculate to be expelled outward during intercourse. By dissecting over the disc space the nerves can stop working, and without this coordinating innervation to the valve, the ejaculate takes the path of least resistance, which is up into the bladder. The sensation of ejaculating is largely the same, but it makes conception very difficult (special harvesting techniques can be utilized). Fortunately, retrograde ejaculation happens in less than 1% of cases and tends to resolve over time (a few months to a year). This complication does not result in impotence as these nerves do not control erection.

There are certain warning signs you should look for after surgery that may indicate a problem, such as excessive bleeding, redness or discharge from the wound, fever, weakness or numbness of the legs, or problems urinating. If you notice any worrisome symptoms, notify your surgeon at once.

What to expect following surgery

Pain: You will feel discomfort and pain at the operative site immediately after surgery. You will be given pain medications; however, the soreness and stiffness in your back and/or limbs will continue for some time. Please ensure you take regular pain relief.

Tingling / Numbness: A degree of tingling and/or numbness in your limbs may be experienced after surgery and may take some time to subside.

Drains: Some patients may return to the ward with a drain tube near the surgical site to help prevent any collection of fluid at the operation site. The drain is usually removed in 24-48 hours.

Drips: You will have a small plastic needle (cannula) to receive fluids and antibiotics during and after surgery. The cannula will be removed when you are drinking sufficient fluids and after the doctor has stopped the prescribed antibiotics.

Catheter: A catheter will be inserted into your bladder under anaesthesia to drain you bladder during and immediately after surgery. This catheter will keep you comfortable, so you will not have to get out of bed to go to the toilet on the first day. The catheter is usually removed the day after surgery.

Calf compressors: Following your surgery, you will have inflatable compressors on your calves to reduce the risk of deep vein thrombosis (DVT). You may also be given a pair of anti-thrombotic stockings.

Coping with the Blues: It is not uncommon for patients to feel a little depressed or emotional after your surgery. The doctors and nurses will help you through this vulnerable phase.

Diet: You will start on a post-operative diet and gradually increase to a full diet. To avoid constipation, you should include plenty of roughage, cereals, fruit & vegetables in your diet. You should also aim to drink 2-3 litres of fluid daily.

Bowels: It is common not to have bowel movements for the first few days. Once you have started on a full diet, you will be given medications to help with bowel movements.

Commonly asked questions:

Will I need a blood transfusion?

Although some blood loss occurs during surgery, a blood transfusion is not generally required. More extensive surgeries may occasionally require a blood transfusion.

How long will I stay in hospital?

The length of your stay in the hospital will depend on the surgical procedure that you have had and can vary from an overnight stay to a week. It will also depend on how your wound is healing. You will be given a rough idea regarding the length of your stay during the pre-surgical education session. However, your surgeon will make a final decision after the operation.

When can I walk?

You will usually be encouraged to begin walking the morning after surgery.

Do I have to wear a back/neck brace?

Yes, you will be required to wear your brace when sitting, standing and walking after surgery. Your physiotherapist will wean you off as appropriate.

When can I have a shower after my surgery?

You can have a shower the day after your surgery. If your dressing gets wet, a new one can be applied.

When do I see my doctor after my surgery?

During your pre-surgical education session, the clinical nurse coordinator will make an advance appointment for you to visit the rooms after you have been discharged from the hospital. This date can be changed depending on the length of your hospital stay. You can usually expect a visit the doctor's rooms 7-10days from surgery, then again at 6weeks, 3 months, 6months, and in some cases 12months after surgery.

Do I have stitches to come out?

The wound is usually closed with dissolvable sutures under the skin and these do not need to be removed. Metallic staples or non-dissolvable sutures, if used, will need removal. On your first appointment (10 days post-op) the surgical wound will be examined and the sutures/staples will be removed.

Do I need to attend physiotherapy sessions?

Following surgery a physiotherapy program will be started to retrain you to maintain good posture and teach you the correct way of moving your spine.

Is there a certain position that I should sleep in at night?

The most important thing is for you to be comfortable. Some people find it comfortable to sleep with a pillow between their legs or under their thighs.

When is it safe to engage in sexual relations?

This is a very personal domain and is left up to you; whenever you think that you and your partner are ready. Clinically, a two-week period is recommended, provided you are the less active partner.

How long should I wait before driving a car?

The recommendation is to wait 3-4 weeks before driving a car. This may vary depending on your surgery and your progression during rehabilitation.

When can I go back to work?

This is assessed on patient-to-patient bases. If you have a physical occupation, it may take up to 3-6 months. With a sedate occupation, you could be back at work as soon as 3 weeks. Do not commence work until you speak to your doctor and physiotherapist.

When is it safe to bend and/or lift items heavier than a bag of sugar?

During the post-surgical physiotherapy sessions, you will be taught the correct way to bend and lift. Bending from the hips is fine if carried out in a controlled manner, but avoid heavy lifting objects (more than 3kg) till your physiotherapy commences.