SPINAL STENOSIS Information for Patients WHAT IS SPINAL STENOSIS?

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1 SPINAL STENOSIS Information for Patients WHAT IS SPINAL STENOSIS? The spinal canal is best imagined as a bony tube through which nerve fibres pass. The tube is interrupted between each pair of adjacent vertebrae, and through these apertures, a nerve root emerges from the spinal canal on either side. With ageing, degenerative changes occur in the spine, as in other joints. These changes include the formation of bone spurs, thickening of ligaments and joint structures, and shrinking of the intervertebral discs associated with narrowing of the openings between the vertebrae. Since the spinal canal is made up of bones and cannot dilate, any increase in the volume of structures within the canal means less space for the nerves. The condition in which spinal nerves are compressed as a result of the above changes is called spinal stenosis. WHAT ARE THE SYMPTOMS OF STENOSIS IN THE LUMBOSACRAL SPINE? Pain in the lower extremities that appears after the patient has walked a certain distance and goes away after a few minutes of rest is the most typical symptom of spinal stenosis. This is called claudication pain. The distance that the patient is able to walk is called the claudication distance. The claudication distance typically decreases with the progression of the disease. Degenerative changes may also give rise to lower back pain and sagittal balance disorders. In severe, long-standing stenosis, nerve roots may be compressed to such a degree that conduction along the affected nerve is stopped. This is manifested as paralysis in the affected part of the lower extremity. In very severe forms of spinal stenosis, bladder and bowel control may be affected as well. HOW IS SPINAL STENOSIS DIAGNOSED? Careful historical and clinical examination are essential for making the correct diagnosis. When spinal stenosis is suspected, x-ray films of the lumbosacral spine are made in two projections to rule out any other pathology. We also perform functional imaging studies to detect possible instability. To see the soft tissue structures of the spine, such as intervertebral discs and nerves, a magnetic resonance imaging (MRI) scan is performed. If this technique

2 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. WHAT BENEFITS CAN BE EXPECTED FROM SURGERY? The benefit expected from surgery for spinal stenosis is a significant increase in pain-free walking distance. WHAT COMPLICATIONS ARE POSSIBLE DURING OR AFTER THE OPERATION? Surgery for lumbosacral spinal stenosis is rarely associated with complications. The following problems may arise during or after the procedure: A nerve root can be damaged during the operation. Severe nerve root damage may lead to complete paralysis of a muscle group. If a nerve root is completely divided, the paralysis will not improve. The dural sac around a nerve root may be torn. Such injuries are usually detected and treated during the operation. A dural tear that is overlooked during surgery will result in leakage of cerebrospinal fluid, requiring a revision operation to close the leak. Major bleeding can occur after the operation. If the drain cannot remove all the blood, a blood clot forms, which may again put pressure on the nerve root. Also in such a case, a re-operation is required, during which the blood clot is removed. Inflammation of the surgical wound is a rare complication; it is managed with surgery and appropriate antibiotics. Lower-back pain may develop due to the further weakening of the connective elements of the spine with the consequent progression of instability and deformity. In

3 some patients, the symptoms of stenosis may reappear. Such cases require additional surgery, which includes fusion of the affected sections of the spine. CAN LUMBOSACRAL SPINAL STENOSIS BE TREATED WITH LESS INVASIVE SURGERY? In this hospital, lumbosacral spinal stenosis is occasionally treated with a surgical procedure that involves the use of so-called interspinous implants. With this method, the spinal canal is not entered. The implants are inserted between adjacent spinous processes to change the angle between the vertebrae, thereby removing pressure from the affected nerve roots. The advantages of this procedure are that it is shorter (15 minutes) and less invasive than the classical open procedure. Unfortunately, the method is not suitable for all patients. Ask your surgeon if you might be a candidate for this type of surgery. ARE THERE ANY ALTERNATIVES TO SURGERY? If you decide not to undergo surgery, symptomatic treatment with pain killers, corsets and regular exercises for the spine may be of help. You should be aware, however, that these measures will probably not stop your disease from progressing further. Your walking distance will gradually become shorter, and your back pain will get worse. You will find it increasingly difficult to straighten your back, and you will tend to lean forward more and more when walking. With further progression of the disease, you may also notice signs of paralysis in your lower extremities and problems with bowel and bladder control. In such cases, immediate surgery offers the only chance of recovery. WHAT HAPPENS ON THE DAY OF SURGERY? You will be admitted the day before your operation. You should bring your health insurance card and a referral note and your medical records you received from your doctor to the hospital. Also bring your x-ray films and MRI scans (on a CD if possible). 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 area with a pen. You will not be allowed to eat or drink anything for at least six hours before the procedure. In the morning before the operation, you

4 may take only those of your regular drugs that have been approved by your doctor. A physiotherapist will check the muscle strength in your legs and teach you how to change your position in bed correctly, and how to sit up and get out of bed safely after the operation. A nurse will take you to the operating suite and leave you with the anaesthesia team. An anaesthesiologist and a nurse will check your identity and prepare you for surgery. Operations for spinal stenosis are performed under general anaesthetic. (The patient is sound asleep during the procedure.) SURGICAL TREATMENT OF LUMBOSACRAL SPINAL STENOSIS The operation usually takes one to two hours. Using an image intensifier, the surgeon marks the site of involvement and makes an incision over the affected sections of the spine. On the side where the stenosis is more severe, the surgeon carefully moves the muscles away from the bony structures at the back of the affected vertebrae, divides the ligament that joins adjacent vertebrae, enters the spinal canal, and removes the bony structures and thickened ligaments that are causing nerve compression. The same procedure is repeated at all affected levels of the spine. After copious irrigation, a drain is placed in the wound to prevent blood from accumulating in the area, and the wound is sutured in layers. If the surgeon notices an area of instability in your spine during the operation, such a section is additionally strengthened with screws and special implants are inserted between the two affected vertebrae. At the end of anaesthesia, you will be moved to the recovery room, where you will remain under constant supervision 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 medication to control the pain. On the ward, you will be visited by a physiotherapist, who will reassess the muscle strength in your legs and teach you exercises to be performed on the operation day. Most patients experience a significant reduction of pain immediately after the operation. The drain is removed on the first postoperative day. Once the drain has been removed, the physiotherapist will help you to get up and start walking about the ward. You will also learn a set of exercises to strengthen the muscles that stabilise your spine. If your leg muscles are weak, electrical stimulation will be applied as well. HOW LONG WILL I NEED TO STAY IN HOSPITAL?

5 The length of your hospital stay will depend on a number of factors. If there are no complications, most patients leave the hospital on the third or fourth postoperative day. WHAT SHOULD I DO AFTER DISCHARGE? Two days after discharge, your wound will be checked and your dressings 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 surgery. Until your follow-up appointment with your surgeon, it is very important that you observe the following instructions: Keep your wound dry until the sutures are removed. Avoid lifting objects heavier than 3kg. Pay attention to your posture and avoid unnatural positions. When picking up objects from the ground, bend at the knees, squat down and do not bend over at the waist. Do your exercises regularly several times a day in line with the programme received from your physiotherapist. Progressively increase your aerobic physical activity on a daily basis (walking). WHO SHOULD I CONTACT IN CASE OF DIFFICULTIES AFTER DISCHARGE? If you have any kind of problems after leaving 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 take your discharge summary from the hospital with you, as well as your x-ray films and MRI scans. 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.