Back pain and numbness in the leg: causes and symptoms

What are the possible causes?

For the past little while, you’ve felt like your back pain is also causing pain or numbness in one of your legs.

How is this possible?

There are two recognized categories of lower back pain:

1. Simple mechanical lower back pain without radiation: back pain without leg pain. Recovery is usually quick and easy, with close follow-up by a health professional.
2. Mechanical lower back pain with radiation: leg pain with or without back pain. Leg pain is often caused by irritation or inflammation of the associated nerve. For example, the sciatic nerve can cause symptoms in the back of the leg. Loss of strength can also occur, due to inflammation or compression of the nerve, or simply because of the pain.

The pain can also radiate to the leg, above the knee, due to irritation or inflammation in the lumbar area, although without the nerve being affected.

This type of problem is generally easy to treat, but recovery time may be a little longer.

Is it serious?

Numbness and pain that extend down into the leg are quite common and not dangerous. For example, these physical symptoms could appear as a result of you forcing or making a false move, or even after being in an awkward position for an extended period of time.

Still, keep a close eye out for certain signs that would need emergency medical attention, such as urinary or fecal incontinence, urinary or fecal retention, severe numbness in both legs, or in the arms and legs.

What to do?

The most important thing is to stay active within the limits of your tolerance. The normal recovery process can take 2-3 weeks. 

If the pain prevents you from working or carrying out your daily activities, or if it persists for more than 2-3 weeks, we recommend that you see a physiotherapist or other health professional qualified to treat these symptoms.

Article written in collaboration with Magali Frève-Marchand, physiotherapist