A “pinched nerve” sensation can occur within the foot and ankle. The proper medical term is nerve entrapment or compression neuropathy. This occurs when surrounding tissues (bones, ligaments, tendons, or soft tissue) place excessive pressure on a peripheral nerve. The compression interferes with the nerve’s ability to transmit electrical signals, leading to disruptive symptoms. The foot is particularly susceptible because nerves must travel through narrow, confined spaces surrounded by rigid structures.
Confirming Nerve Compression in the Foot
Nerve compression in the foot manifests through distinct sensory and motor symptoms, differing from common joint pain or muscle strain. The most recognizable symptom is paresthesia, describing unusual sensations like tingling, “pins and needles,” or a foot falling asleep. This occurs because physical pressure disrupts the protective myelin sheath, causing erratic signal transmission.
Patients often report sharp, shooting, or burning pain that follows the specific path of the affected nerve. This neuropathic pain can sometimes feel like an electric shock or a deep ache. In advanced cases, compression may interrupt motor signals, leading to localized muscle weakness or even atrophy in the foot and toes.
Distinguishing these symptoms from other causes of foot discomfort is important, as pain frequently worsens with specific movements or pressure that irritates the nerve. For instance, wearing tight shoes or prolonged standing might increase mechanical pressure on the compressed area. Burning and tingling sensations that radiate along the nerve’s distribution strongly indicate an underlying nerve issue.
Common Types of Foot Nerve Entrapment
Two frequently diagnosed forms of nerve entrapment involve the ankle (compression) and the forefoot (irritation). Tarsal Tunnel Syndrome (TTS) results from the compression of the posterior tibial nerve. This nerve travels through the tarsal tunnel, a narrow passageway along the inside of the ankle, beneath the flexor retinaculum.
Swelling from an injury, a bone spur, or a cyst can narrow this tunnel, squeezing the nerve and its branches. Symptoms typically include burning pain, tingling, or numbness radiating into the sole, heel, and sometimes the toes. The discomfort often intensifies with physical activity or prolonged standing because pressure on the nerve increases.
A condition known as Interdigital Neuroma, commonly referred to as Morton’s Neuroma, represents another frequent nerve issue in the forefoot. While not a classic “pinched nerve,” it involves the thickening and inflammation of the tissue around the digital nerves. This typically occurs between the third and fourth metatarsal bones near the ball of the foot.
The irritation leads to a painful, sharp, and burning sensation, often described as feeling like walking on a marble or a bunched-up sock. This condition is aggravated by footwear that squeezes the toes together, which puts constant pressure on the irritated nerve tissue. Unlike TTS, Morton’s Neuroma is a reactive change within the nerve sheath, caused by chronic irritation from the adjacent bones.
How Doctors Diagnose Nerve Issues
Diagnosis begins with a thorough physical examination, including specific maneuvers to reproduce symptoms. A physician might perform a Tinel’s sign test by gently tapping over the suspected compressed nerve site, such as the path of the posterior tibial nerve for Tarsal Tunnel Syndrome. A positive result is indicated by a shooting pain or tingling sensation radiating into the foot or toes.
For Morton’s Neuroma, a clinician will often use the “thumb index finger squeeze test” to compress the space between the toes, attempting to elicit the characteristic sharp pain or sometimes a palpable click. Plain film X-rays are typically ordered first, not to visualize the nerve, but to rule out other causes of pain, such as stress fractures or arthritis.
Advanced imaging is used to visualize the soft tissues surrounding the nerves. Ultrasound is highly effective for identifying a Morton’s Neuroma, as it clearly shows the thickened nerve tissue and guides diagnostic injections. MRI may also be utilized if the diagnosis is unclear or if other soft tissue abnormalities, such as a mass or cyst, are suspected to be the source of compression.
Nerve Conduction Studies (NCS) and Electromyography (EMG) provide objective information on nerve function. The NCS measures the speed and strength of electrical signals traveling through the nerve, which can be slowed or weakened at the point of entrapment. EMG involves placing a small needle electrode into the muscles to assess their electrical activity, helping to determine the severity and location of the nerve damage.
Treatment Options for Relief
Treatment for foot nerve entrapment typically follows a stepped progression, beginning with conservative measures. Initial management involves rest, ice application, and the use of nonsteroidal anti-inflammatory drugs (NSAIDs) to decrease swelling. Modifying footwear is important, often requiring wider shoes with a lower heel to minimize forefoot pressure.
Custom orthotic devices or arch supports can be effective by altering the foot’s biomechanics to reduce tension on the entrapped nerve, such as redistributing pressure away from the neuroma or reducing the strain on the tibial nerve in TTS. Physical therapy may also be prescribed, focusing on gentle stretching and exercises to improve flexibility and decrease localized swelling.
If conservative treatments do not provide sufficient relief, interventional options are considered. Corticosteroid injections, often guided by ultrasound, deliver a powerful anti-inflammatory agent directly to the site of nerve compression. For Morton’s Neuroma, a series of alcohol injections may be used to chemically ablate the nerve tissue, offering a permanent resolution of pain.
Surgical intervention is reserved for patients whose symptoms persist despite comprehensive non-surgical care. For Tarsal Tunnel Syndrome, the procedure involves surgically releasing the flexor retinaculum, known as tarsal tunnel release, to decompress the posterior tibial nerve. In cases of Morton’s Neuroma, a neurectomy is performed, which involves removing the thickened nerve tissue to eliminate the source of pain.