Pregnancy and Sciatica
Pregnancy-related sciatica usually responds to conservative management. Although back pain is a common complaint during pregnancy, sciatica-related back pain is rare in pregnant females.
The sciatic nerve is a large nerve originating near the lower spine and travels down the pelvis to enter the back of the thigh. The nerve supplies the major muscles in the thigh, legs, and feet. The nerve is also responsible for transmitting the sensory signals from the feet, legs, and the back of the thigh.
The nerve roots (L4, L5, S1, S2, and S3) exit the neural foramen at different levels and join together to form the sciatic nerve. Any compression or narrowing of the space available for the nerves may lead to the symptoms of sciatica.
A prolapsed intervertebral disc is a common culprit as the herniated disc may impinge upon the exiting or traversing nerve roots. A prior disc bulge or herniation may get exacerbated during pregnancy. Pregnancy is associated with weight gain which may add to the increased pressure on the intervertebral disc.
The center of gravity of the body changes as the abdominal girth increases, the body tries to align the center of gravity by increasing the backward curve of the lower spine and tilting the pelvis forward. This may increase the amount of force acting on the intervertebral discs and discs may herniate.
During pregnancy, a hormone known as relaxin is released especially during the end trimester. The relaxin hormone aids to relax the ligaments and joints of the pelvis for the smooth delivery of the baby. There may be an association of relaxation of the ligaments in the spine that may lead to herniation of the intervertebral disc.
Back pain is a common symptom in pregnancy that is mostly unrelated to sciatica but a physician’s examination may be necessary to differentiate different causes of the back pain. Pregnant females may complain of pain in the buttock/lower back that may radiate down to the leg or the toes. The pain may be associated with a feeling of burning or tingling.
In some cases due to significant compression of the nerve roots, there may be symptoms of weakness and numbness in the legs. Rarely, patients may complain of bowel or bladder incontinence.
The physician may examine and conduct a physical examination to localize the cause of symptoms. The physical examination may include tests to check the power and sensory integrity of the spine in the lower extremities. Almost all cases of sciatica are diagnosed clinically and do not require imaging.
Sciatica in pregnancy is managed with conservative methods. The patients are encouraged to continue staying active and avoid activities that exacerbate the symptoms. Conservative management consists of the use of pregnancy-safe pain relief medications such as Tylenol. Medications such as nonsteroidal anti-inflammatory medication like ibuprofen are avoided in pregnancy.
Patients are often advised to modify their activities and their sleeping positions to achieve relief. Physical therapy is recommended to improve flexibility and strengthen the muscles around the back. Exercises in pregnancy are only recommended only under the observation of a trained therapist.
Cold therapy may be used in patients with sudden onset of sciatica. Cold therapy works by numbing the nerves responsible for transmitting the pain signals and reducing the blood flow to the affected segment. The reduced blood supply decreases the number of inflammatory cells reaching the area, thus reducing pain and swelling. The cold therapy may be given by applying ice packs to the affected area.
In the case of chronic sciatica, heat therapy may benefit the patients by increasing the blood flow to the affected area. The increased blood flow helps by increasing the number of nutrients reaching the site of inflammation, resulting in quicker recovery. The heat therapy may be done with a warm bottle or a warm heating pad.
The patients who do not benefit from a trial of conservative therapy for 4-5 weeks may benefit from epidural or transforaminal steroid injection. The local injection of the steroid in the affected area reduces the inflammation and provides relief from symptoms. The injection may provide relief for a few months and maybe repeated to extend the relief.
Surgical management is rarely indicated for sciatica in pregnancy. The majority of the pregnant females experience significant relief from sciatica symptoms after the delivery. Surgery may be required immediately in patients in whom there are signs and symptoms of cauda equina syndrome. The symptoms of cauda equina syndrome include loss of bowel/bladder control, numbness of the saddle area, and weakness/numbness of the legs.
Surgery may also be required in patients with worsening symptoms and signs of motor/sensory weakness. The timing, type, and approach of the surgery depend upon the level of nerve root compression and the gestational age of the child. Usually, a microdiscectomy or endoscopic disc removal surgery may be performed. Sometimes, the surgery may be postponed until the birth of the baby.