Plantar fasciitis is often characterized by pain on the underside of the foot that is aggravated by walking, climbing stairs, or standing on tiptoe. The condition often occurs following a change to your walking or running habits: greater distances, hilly terrain, increased frequency, faster speeds, different shoes, etc. Wearing high heels too frequently or for longer periods of time may also be the cause.
When the pain is similar to plantar fasciitis, but the context makes it unlikely, it’s wise to consider whether the back (lumbar) might be involved.
These are the clinical characteristics observed:
Characteristics of the pain
- Pain in the morning after taking just a few steps, or even pain at night
- Pain caused by something other than the standing position or the stretching of the plantar fascia
- Burning sensation or feeling of electric shock under the foot
Location of the pain
- Pain experienced in both feet, sometimes intermittently
- Slow, progressive emergence of pain, lasting over 3 months
- Variable location of pain on the underside of the heel: sometimes internal, sometimes external
Other signs and symptoms
- Pronounced muscular tension in the calves (gastrocnemius)
- An episode of lumbar pain within the past year or concurrently
- Numbness in the foot
- Reduced mobility of the implicated nerve in the leg
- Weakness and muscle fatigue corresponding to nerve roots L5 and S1
A lumbar problem can actually cause pain on the underside of the feet for several anatomical reasons:
- The origin of the electrical current in the leg, manifesting in the calf and the underside of the foot, is the lumbar nerve roots L5 and S1.
- The tibial nerve, a branch of the sciatic nerve, passes through the interior of the ankle, close to the heel.
During your evaluation, the physical therapist will be able to determine whether the cause of the heel pain you are experiencing is actually plantar fasciitis or something else. With the help of personalized questions and testing, s/he will be able to detect any underlying lumbar conditions in order to identify and treat the true source of your problem.