What’s the equation between the spine and the foot?

A series of spinal nerves from your lower spine travel down your legs and terminate in your feet. When the nerve roots (part of the nerve as it exits the spine) of these spinal nerves are irritated or compressed, foot pain can occur. Foot pain can also occur if a nerve is compressed near your hip, knee, or in your foot.

Foot pain caused by a spinal problem

Nerve root irritation or compression in the lumbar or sacral spine (lower back) may cause sciatica pain to radiate down your leg and into the foot.¹ Specifically, compression of the S1 nerve root, also called classic sciatica, can cause pain along the outer side of your foot.²

Nerve roots may be compressed or irritated due to a number of causes. Common examples include³:

• Lumbar herniated disc: Leaking of the inner contents of an intervertebral disc
• Lumbar degenerative disc disease: Age-related changes causing narrowing and shrinkage of the disc
• Spondylolisthesis: Slipping of a vertebra over the one below it
• Lumbar spinal stenosis: Narrowing of the bony openings for spinal nerves and/or the spinal cord

The inability to lift the front part of your foot or frequent tripping while walking may be due to a condition called foot drop. This condition is typically caused due to compression of the L5 nerve root. Rarely, compression of the L4 and/or S1 nerve roots may also cause foot drop.⁴

Foot pain caused by compression of nerves in the hip, knee, or leg

Foot pain can also occur when nerves are compressed or damaged along their path in the hip, knee, or leg. For example:

• Peroneal neuropathy, a condition where the peroneal nerve is compressed or injured near the knee may cause foot pain and foot drop when you try to move your foot.⁵
• Sciatic neuropathy or damage to the sciatic nerve in the pelvic region (hip) may cause foot pain along the top of your foot with some degree of weakness.⁶
• Tarsal tunnel syndrome or dysfunction of the tibial nerve within the tarsal tunnel of the inner ankle may cause a sharp, shooting pain in your ankle area and along the sole of your foot.⁷
• Sural nerve entrapment can occur in the leg or near the ankle and typically causes shooting pain along the outer side of your ankle and/or foot.⁸

Additionally, a corn may develop on the skin around your toes. Corns grow over time as a result of excessive friction, and they can compress nearby nerves, causing pain and other symptoms. Another possible cause of nerve pain in your foot is Morton’s neuroma, which is a thickening of the tissue around a nerve in the foot.

Read more about Causes of Leg Pain and Foot Pain

How to identify the source of your foot pain

With all the possible causes of nerve pain in the foot, it may be difficult to pinpoint the exact underlying cause. Here are a few useful signs to help you identify the source of your foot pain:

• Foot pain that follows recent trauma to the lower back, hip, knee, or ankle may help indicate the site of nerve damage
• Foot pain due to nerve root compression or sciatica may also be associated with other symptoms, such as pain, numbness, and/or weakness in the buttock, thigh, and leg; and typically affects one leg at a time
• Foot pain that develops after wearing tight boots or shoes may indicate peroneal or sural nerve compression near the knee or ankle
• Foot pain that develops after a hip injection or hip surgery may indicate sciatic neuropathy

Nerve pain in the foot may also occur due to nerve damage from systemic conditions, such as diabetes or multiple sclerosis.

Twisting, bending, or a direct hit on your ankle and/or foot may injure the foot bones, ankle joint, blood vessels, muscles, and/or tendons, causing foot pain.