Know about sciatica

“Sciatica”, is a term used for any pain or parasthesias, i.e. abnormal sensations occurring in the legs or feet. Technically it is the compression of the sciatic nerve or its roots in any part of its course from the lumbar spine to the buttock to lateral aspect of the leg and foot. The sciatic nerve is the longest nerve in the human body. It arises from the between the lumbar vertebrae, passes below the buttocks, from the outer side of the thigh to the legs it ends at the foot. During its long course, it is prone to compression or injury at any point. The most common cause for sciatic nerve compression happens to be a lumbar spondylosis. This is a degenerative change occurring in the elderly, where the disc space between the lumbar vertebrae is reduced and tiny new spicules of bone called osteophytes are formed. Both reduction of the space and the presence of spicules can cause compression of the sciatic nerve. Similarly herniation of the intervertebral disc can cause sciatica in both the young and old alike. Apart from these reasons, spinal tumors, infections or trauma of any kind can lead to sciatica. At times there may be spread of cancer to the back bone from any other part of the body; notably cancers from the stomach, breast, thyroid, lung, e.t.c., parts commonly spread to the back bone. This bony metastasis can also precipitate the problem of sciatica by pressing on the sciatic nerve. Earliest symptom may be pain in the lower back which may radiate to the hip, thigh and the lower limb towards the outer side. This pain is typically aggravated by movements, particularly bending from the back or walking or lifting legs up. If the nerve roots are compressed, pain can also be induced by coughing. Relief is obtained when one stops any of these movements and lies down or sits with legs spread straight. Along with the pain, one may feels abnormal sensations in the outer side of the thigh and legs. There may be sensation of insects crawling over legs or tingling. In severe cases one may feel numb over the affected part and there may be loss of sensation. The intensity of the symptoms depends on the part of the nerve compressed. In case of involvement of the nerve roots alone, the pain is localized to the lumber region of the back. In case of affection of the main nerve, pain and parasthesias can be felt along its entire course. I have seen patients who are virtually crippled and have to drag their legs while walking due to severe pain of sciatica. This condition is easily diagnosed by clinical features. When parasthesias are induced by elevation of the legs, it confirms the suspicion of sciatica. Other advanced investigations like C.T. scan and MRI are done to know the cause of sciatica. Myelography(visualization of the spinal cord after injecting a dye) is done in case of suspected tumors of the spinal cord. The conservative symptomatic treatment of sciatica consists of bed rest on a hard bed with the back kept straight. After the pain is reduced walking and weight bearing is allowed and increased gradually. One is advised to keep the back straight, well supported and avoid bending. In persons suffering from chronic sciatic pain, a belt is advised to be worn while standing or walking as this helps in easing the pain while sharing some of the weight of the body. Pain killer tablets or injections are used to diminish the pain. Supplements of vitamin B-complex are used to provide relief from the troublesome parasthesias. If a definite cause for sciatica is fond which is treatable surgically, surgery is done. After treatment, when the individual is free from pain, regular exercises to strengthen the back and limb muscles help in further improvement. If one is prudent to keep the back straight, use a hard bed and do regular exercises, one can prevent sciatica, or minimize its symptoms. E-mail-rachna212002@yahoo.co.uk