Symptoms of numbness, tingling, pain, and weakness in the legs and feet are common in older adults. These symptoms can be caused by several different problems. Narrowing of the opening around the spinal nerve root is one of the causes.
The spinal cord travels through the spinal canal. Nerve roots leave the spinal cord and exit through a small opening on the sides of each vertebral pair. Narrowing of these openings in the low back area is called lumbar spinal stenosis (LSS).
Most often, symptoms of LSS appear in the low back, buttocks, and legs. The most common symptom of LSS is calf or leg pain (or cramping) with walking that goes away when walking is stopped. This is called neurogenic claudication.
Diabetes is another potential cause of painful numbness and tingling. Damage to the nerves from the disease result in a condition called diabetic neuropathy. These symptoms can affect the arms and hands as well as the legs and feet.
Many older adults have one of these problems, or sometimes both at the same time. The treatment for each condition is different. Therefore, finding out what is causing the symptoms is important. This study looked at various tests used to diagnose LSS and neuropathy, including the exercise treadmill test (ETT) and electromyography (EMG).
Walking on the treadmill was the most helpful for identifying LSS. It showed that patients who had neurogenic claudication covered much less distance and at a slower pace than those who didn’t have claudication.
EMG studies show that nerve messages to the muscles are slowed down for both groups (LSS and diabetes). However, this change was greatest for diabetic patients with problems in both the arms and legs. EMG changes are only present in the legs for patients with LSS.
The authors of this study advise that the exercise treadmill test has some limitations. Walking may end early because of other problems such as shortness of breath or joint pain. Patients who stop walking early should be evaluated carefully before being diagnosed with LSS.