Sciatica (Lumbar Radiculopathy)

Lumbar radiculopathy more commonly known as sciatica means a radicular pattern of pain, which arises from the back of the hip and goes into the leg in a specific pattern. Sciatica literally means along the pain caused due to the sciatic nerves. Sciatica is a term used for the pain, which arises from the thigh due to the compression of the nerve roots.

The sciatic nerve is formed by the combination of nerve roots from L4 to S3 from the lumbar spine. Compression of any one of those nerve roots can lead to a typical pattern of symptoms. The most common cause of sciatica is disc degeneration and herniation. Though the most common cause of sciatica is compression of the nerve root from the back, it can also be caused by other problems affecting the sciatic nerve.

This pain may or may not be associated with tingling or numbness. Rarely, this can be associated with weakness, gait abnormality, imbalance, bowel or bladder involvement.

Axial section of the Lumbosacral MRI at L4-L5 level.

Sagittal section of the lumbosacral on MRI.

Presentation Or Symptoms Of Sciatica

Sciatica presents by the typical pattern of pain going down either from the outside of the thigh and leg into the top of the foot or from the back of the thigh and leg into the bottom of the foot due to involvement of L5 or S1 respectively. It can occasionally present with pain along the side in front of the thigh bone into the inner side of the front of the leg due to the involvement of the L4 nerve root.

It can rarely present with pain along the front of the thigh if it involves the nerve roots of L2 or L3. Though these nerve roots are not part of the sciatic nerve, the pain is still referred to as sciatica.

These pain can similarly be associated with tingling and numbness in specific areas, which are supplied or innervated by these nerve roots.

Pain affecting the nerve roots of L2, L3 can also weaken the hip joint. Similarly, pain and sciatica involving the nerve roots of L2, L3, L4 can cause weakness of the knee also. Nerve roots involving L5 and S1 can cause weakness in the ankle.

The weakness can lead to limping or stumbling with loss of balance. Patients may have to use a crutch or a cane to maintain their balance. They may be unable to walk up and down the stairs or get in and out of the car. They may have difficulty getting up from the chair or from the ground.

Rarely, these patients may have involvement of bowel or bladder in which case they may not be able to control the process of defecation or urination and may have incontinence. They may also have decreased sensation in their perigenital areas.

Diagnosis

A diagnosis of sciatica is a clinical diagnosis. Patients have a typical presentation, which is not commonly associated with any injury or fall. These patients may have had symptoms of back pain at the time of presentation or in the past. Sometimes, the patient may have no back pain at the time of the presentation.

X-rays are usually done on their first visit to look for any gross abnormality and rule out any instability. Patients are usually treated with conservatively means initially. Patients may also need to undergo advanced imaging like MRI to confirm the diagnosis.

Occasionally, patients who have confusing symptoms or may have comorbidities like diabetes or other neuropathies may need to undergo nerve conduction study and electromyographic studies.

Treatment and Management

The initial treatment for sciatica is conservative treatment, which includes medications and physical therapy. Anti-inflammatory medications, as well as pain medications along with some neuro-behavior modifying medications, can be used for suppressing the pain.

Physical therapy can be done by the patient at home, but has better results with outpatient physical therapy. The therapy is centered around stretching as well as strengthening the core muscles of the back. These include the muscles of the front and the back of the torso. Also, physical therapy for hip and knee muscles is performed. Patients are also helped with gait especially those who have a weakness.

Patients who do not get better with these conservative means can undergo nerve root block or epidural injection. These cortisone injections are directed to the nerve root which is irritated and inflamed. These injections help with decreasing the inflammation and hence decreasing the pain.

If the compression is not severe, our human body is capable of taking care of it in the due course of time. The patients who have recurrent pain can either have repeat injection or may need surgical management depending on the recurrence and severity.

Surgery is performed for patients who do not get relief with either conservative management or injection over 4 to 6 weeks. Sometimes, the patient may have acute worsening of the neurological status or involvement of bowel or bladder. These patients as well as those who have severe pain, which is not relieved by medication, may need urgent surgical management. Patients who have involvement in bowel or bladder may present with cauda equina syndrome, which is an emergency.

Surgery involves decompressing the nerve roots and removing the pressure from the nerves. Usually, this can be done in a minimally invasive fashion. Small incisions were used to reach the nerve root from the back. The bone and the redundant ligamentous tissue from over the nerve root is removed. If the compression is over more than one nerve root or on both sides then similar surgery is performed on all the levels. Occasionally, patients may have instability in the vertebral segment in such cases a fusion surgery may be required.

Recovery

90% of patients do well without surgery. Patients who are treated with or without surgery for sciatica usually do well in the long term. They may have a recurrence of pain either at the same level or adjacent levels due to ongoing aging and wear and tear. Such presentations are again treated in a similar fashion. Patients who undergo surgery usually get better in 3 to 6 weeks. Patients who undergo fusion surgery may take a little longer for recovery.

Prognosis

Overall, the treatment of sciatica has a good prognosis. Patients have good relief having been treated with or without surgery. Pain is relieved relatively early in the treatment course. Patients who have numbness and weakness may take more time and may have incomplete recovery. Patients who have involvement of bowel and bladder if treated urgently may have a good recovery.

Conclusion

Sciatica is a life-affecting disease process, which frequently needs treatment. 90% of patients can do well without surgery. The recovery from surgical or nonsurgical treatment is good. Patients will have consistent and good relief of pain. Patients may have residual back pain or incomplete recovery from numbness or weakness.