HERNIATED (SLIPPED) DISC IN LOWER BACK

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1 HERNIATED (SLIPPED) DISC IN LOWER BACK Information for Patients WHAT IS AN INTERVERTEBRAL DISC? WHAT IS A DISC HERNIATION? An intervertebral disc is a very complex structure lying between two adjacent vertebrae. It is made up of two parts: a pulpy semi-liquid core surrounded by a concentrically arranged fibrous ring. A healthy intervertebral disc is essential for the normal biomechanics of the spine. It serves as a cushion against forces acting on the spine. Degenerative changes in the intervertebral disc occur earlier than in other organs. The exact cause remains unknown. In all likelihood, the degeneration of cells in the disc is a consequence of ageing, genetic predisposition, reduced nutrition supply, and constant longterm mechanical loading. The same degenerative changes occur in women on average a decade later than in men. With advancing age, the intervertebral disc loses some of its water content and shrinks, becoming increasingly stiff and rigid. In such a disc, bulging may develop or disc material may even be extruded into the spinal canal. In the lumbosacral area, such a herniated disc may press on one or, rarely, several nerve roots that supply the lower extremities or control the function of the bladder, the sphincter muscles and external genitalia. WHAT ARE THE SYMPTOMS OF A HERNIATED DISC IN THE LOWER BACK? The most frequent symptom of a herniated disc in the lumbosacral region is pain that radiates from the low back into one or, rarely, both legs along the course of the affected nerve. The pain is accompanied by tingling and sensory changes in the affected region. It is usually made worse by coughing and straining. It can be so severe as to be completely incapacitating, forcing the patient to maintain a position in which the pain is bearable. If the herniation is large, a nerve root can be damaged to such an extent as to result in muscle weakness or even complete paralysis of the affected muscle group. The patient becomes aware of being unable to walk on the toes or heels, or of a leg giving way during walking.

2 A serious complication is injury to the nerve roots responsible for bladder and bowel control. The patient may notice urinary incontinence or inability to pass urine, and decreased sensation to touch in the region of the external genitalia, around the anus, and on the inside of the thighs. HOW IS A HERNIATED DISC DIAGNOSED? Careful patient history and clinical examinations are essential for making the correct diagnosis. When a disc herniation is suspected, x-ray films of the lumbosacral spine are made in two projections to rule out other pathology. To reveal the soft tissue structures of the spine, such as intervertebral discs and nerves, a magnetic resonance imaging (MRI) scan is performed. If this technique cannot be used because a metal object is present in the patient s body, we carry out a computerised tomography (CT) scan with simultaneous application of a contrast medium into the fluid surrounding the nerve roots. In most cases, the correct diagnosis can be made on the basis of the above tests. In rare cases of doubt, the patient also undergoes an electromyography (EMG) test, which provides information on the function of peripheral nerves. A bone scan is an imaging technique that involves injecting a radioactive tracer solution into the patient s blood and following its accumulation in the bones with a special camera. It is used when a disc infection or a pathological process within the vertebrae is suspected to be causing the patient s symptoms. WHEN IS SURGICAL TREATMENT INDICATED? Emergency surgery is indicated if the patient has problems with bladder or bowel control or develops a muscle weakness in a lower extremity. In these two instances, the operation is performed as soon as the necessary diagnostic tests are completed. Elective surgery is contemplated when symptoms continue to persist after six weeks of conservative treatment and the patient agrees to the operation. In such a case, it is reasonable for the patient to complete the diagnostic evaluation before seeing an orthopaedic surgeon.

3 WHAT COMPLICATIONS ARE POSSIBLE DURING OR AFTER THE OPERATION? Spinal surgery for a lumbosacral herniated disc is rarely associated with complications. The following problems may arise during or after the procedure: A nerve root can be damaged, leading in the worst case to complete paralysis of a muscle group. If the damaged nerve root is completely divided, the paralysis will not improve. The dural sac around a nerve root may be damaged or torn. Such an injury is usually detected and treated as early as during the operation. If the injury is overlooked, leakage of cerebrospinal fluid will develop, requiring a revision operation to close the leak. Major bleeding can occur after the operation. If the drain cannot remove all the blood, a clot forms, which may again press on the nerve root. Also in such a case, a reoperation is required, during which the blood clot is removed. Inflammation of the surgical wound is a rare complication, which is managed with surgery and appropriate antibiotics. Inflammation of the operated disc is an extremely rare but serious complication. If not detected in time, it is likely to require a second, more extensive operation involving fusion of the affected segment of the spine and prolonged antibiotic treatment. Recurrent herniation at the same level is a realistic possibility. It occurs in 5 to 10% of patients. Chronic lower back pain due to progressive disc degeneration occurs in 15% of operated patients and mostly responds to conservative treatment. A minority of patients undergo a spinal fusion procedure. IS THERE A LESS INVASIVE SURGICAL PROCEDURE? At our department, lumbosacral disc herniation can also be treated by endoscopic (keyhole) surgery. With this technique, the surgeon removes the herniated disc through a very small

4 incision (less than 1cm) using a camera and special instruments. The advantages of endoscopic surgery are less tissue damage (bony parts of the spine are not removed) and, consequently, faster recovery. The procedure takes a little longer than a traditional operation. It is applicable in only about 10% of patients since accurately defined anatomical criteria must be met. Talk to your surgeon about the possibility of having an endoscopic operation. ARE THERE ANY ALTERNATIVES TO SURGERY? If you decide not to undergo surgery, your problems due to the herniated disc can be treated conservatively with exercises and with painkillers taken as required. Studies have shown that after 10 years, the condition of patients who underwent surgery for a herniated disc is the same as that of patients who were treated only conservatively. In many patients, the herniation material that has escaped into the spinal canal even undergoes complete resorption. The difference is that after an operation, the symptoms resolve immediately, whereas with conservative treatment they may persist for months or even years. Two exceptions are paralysis of recent onset in a lower extremity, and problems with bowel or bladder function. In such cases, immediate surgery offers the only chance of cure. WHAT HAPPENS ON THE DAY OF SURGERY? You will be admitted a day prior to the operation. You should bring to the hospital your health insurance card and a referral note and medical records received from your doctor. You will be asked to sign a consent form for surgery and anaesthesia, and you will meet your surgeon, who will answer any questions you may have. During the morning ward round, for your safety, the surgeon will mark the affected leg with a pen. No food or drink is allowed for at least six hours before the procedure. In the morning before the operation, you may take only those of your regular drugs that have been approved by your doctor. You will be asked to remove all your jewellery and take a bath or a shower. A nurse will take you to the operating

5 suite and leave you with the anaesthesia team. An anaesthesiologist and a nurse will check your identity and prepare you for the operation. The operation is performed under general anaesthetic. (The patient is sound asleep during the procedure.) SURGICAL TREATMENT OF A HERNIATED DISC IN THE LOWER BACK The procedure usually takes between 30 minutes and one hour. Using an image intensifier, the surgeon marks the site of involvement and makes a 3 to 4cm long incision over the affected area of the spine. On the affected side, the surgeon carefully pushes the muscles away from the bony structures on the back of the adjacent vertebrae, divides the ligament that joins them, enters the spinal canal and removes a small amount of bone to expose the affected nerve root, which is gently pulled away and the underlying hernia is removed. Next, the surgeon locates the site of herniation and removes any loose fragments of the disc. After copious irrigation, a drain is inserted to prevent blood from accumulating in the area, and the wound is sutured in layers. At the end of anaesthesia, you will be moved to the recovery room, where you will be closely monitored until you are fully awake and your vital functions are stable. In the meantime, your surgeon will perform a neurological examination. You will then be transferred to the ward, where you will receive the prescribed medication to control your pain. On the ward, you will be visited by a physiotherapist, who will reassess the muscle strength in your legs, teach you how to turn or roll over in bed correctly, and explain the prescribed programme of exercises for strengthening the muscles that stabilise your spine. Most patients experience a significant reduction of pain immediately after the operation. The drain is sometimes removed as early as the day of surgery but mostly on the first postoperative day. You will then be allowed to get up and walk about the ward. HOW LONG WILL I NEED TO STAY IN HOSPITAL? The length of your hospital stay will depend on a number of factors. If there are no complications, most patients leave hospital on the second postoperative day.

6 WHAT SHOULD YOU DO AFTER DISCHARGE? Two days after discharge, your wound will be checked and your dressing changed by your GP, who will also remove your sutures on the 12 th postoperative day. Your surgeon will want to see you six weeks after your operation. In the period until your first follow-up appointment with your surgeon, it is essential that you adhere to the following instructions: Keep your wound dry until the sutures are removed. Avoid lifting objects heavier than 3kg. Pay attention to your posture; avoid unnatural positions. When picking objects up, bend from the knees, squat down and do not bend over at the waist. Do your exercises regularly several times a day according to the programme received from your physiotherapist. Progressively increase your aerobic physical activity (walking) on a daily basis. WHO SHOULD I CONTACT IN CASE OF DIFFICULTIES AFTER DISCHARGE? If you have any kind of problems once you have left hospital, first talk to your GP or, outside regular working hours, the doctor on duty in your community health centre. When seeing a doctor, always bring your discharge summary with you. In case of a major complication, your doctor will arrange an urgent appointment with an orthopaedic surgeon. If a bacterial infection is suspected, you must not take any antibiotics before seeing an orthopaedic surgeon.