Q: My 19-year-old son has been diagnosed with lumbar sacral plexopathy. Could you please explain what this is? What causes this illness, will he recover and are there complications? Also, will he be able to exercise, such as run and play basketball? Does he need medication to control the condition?

A: Plexopathy means a disorder involving a network of nerves. The different location of these branches (or plexus) of nerves will determine the location of the symptoms.

Our bodies have many networks of nerves. These include the lumbar sacral plexus, which controls the branches of nerves that principally control lower limb, bladder and bowel functions.

Symptoms of plexopathy range from pain, tingling sensations, pins and needles to weakness of muscle groups. The symptoms can be mild, moderate or intractable pain.

There are many causes of plexopathy. These include disc herniation (commonly known as 'slipped disc" which can lead to irritation and compression of spinal nerves resulting in back and leg pain), trauma, diabetes, haemorrhage, neoplasm (cancer) and complications following surgery (iatrogenic cause).

Tests are needed to investigate the cause. The most useful are an electromyography (EMG) - a test where the function of the nerves are assessed by using electrodes and sensors to study the transmission of nerve signals to certain muscle groups - and a nerve conduction study (NCS).

The patterns of the findings of the EMG and NCS can help locate and determine the cause of the condition and its prognosis.

Radiological investigations like an MRI, plain X-ray and CT scan will be able to help diagnose traumatic or neoplastic causes (the underlying cause may be due to trauma or cancerous growth pressing on the spinal nerves).

Treatment-wise, the primary goal is restoration of normal nerve function. However, where there is already progressive lesion, preservation of the nerve function for as long as possible is the main goal. Treatment include pain medication, nerve stabilising medication and supplements and, in some instances, surgery to treat the underlying cause.

In your son's case, once the cause has been determined, the physician or surgeon managing his condition will be able to assess the severity of his illness and advise you on whether and how well he will be able to recover and return to his normal activities.

Dr Razmi Rahmat is a consultant orthopaedic and spine surgeon at Gleneagles Hospital.

This article was first published in Mind Your Body, The Straits Times.