When looking at the wisdom of Donguibogam through the lens of modern medicine, sole pain and numbness can be closely connected to tarsal tunnel syndrome. Tarsal tunnel syndrome is a condition caused when the posterior tibial nerve, which passes through a narrow space called the tarsal tunnel beneath the inner ankle bone, becomes compressed due to various factors. This posterior tibial nerve governs sensation in the soles and toes, as well as the movement of small muscles inside the foot.
Much like vehicles backed up in a narrow tunnel, when the nerve is compressed inside the tarsal tunnel, issues arise in nerve signal transmission, producing varied symptoms. The most common symptoms are tingling, burning, numbness, or dulled sensations felt in the soles, toes (especially from the big toe to the fourth toe), and the inside of the heel. In particular, symptoms tend to worsen at night, or after standing or walking for long periods. In severe cases, people also report a loss of strength in the foot or nighttime cramps.
The causes of this nerve compression are diverse. Trauma around the ankle, such as fractures or sprains, and structural issues like ankle osteoarthritis, flatfoot, or plantar fasciitis can narrow the space inside the tunnel. Abnormal growths such as a cyst, lipoma, or hemangioma may also form near the nerve to compress it directly. In addition, when there is edema during pregnancy, neuropathy due to systemic conditions like diabetes, or an accompanying metabolic disorder like hypothyroidism, the risk of tarsal tunnel syndrome increases.
Here, we can connect the concept of dampness-phlegm from Donguibogam to modern medicine. The idea that dampness-phlegm obstructs the circulation of qi and blood corresponds in modern medicine to a microinflammatory response, edema, and blood circulation disorder around the nerve. When inflammation or edema occurs, pressure inside the tunnel rises and compresses the nerve further, which hinders the supply of nutrients and oxygen to the nerve and can accelerate nerve injury.
Diagnosis is mainly made through evaluating symptoms alongside a neurological examination to check for a positive Tinel's sign, a nerve conduction study, and electromyography. Through these detailed evaluations, it is crucial to differentiate this from other conditions that cause sole pain, such as plantar fasciitis, lumbar disc herniation, or peripheral neuropathy, to identify the exact cause.
If tingling and numbness in the soles are dismissed as mere fatigue and left unaddressed, nerve injury can become chronic and lead to permanent hypoesthesia or muscle weakness. The feet are the foundation of our bodies and support our daily lives. Paying attention to small discomforts and consulting a specialist for proper care is a practical way to protect the health of your feet.
