Achilles Tendinitis — When the Area Above the Heel Hurts
Table of Contents
Anatomy of the Achilles tendon
The Achilles tendon is the largest and strongest tendon in the human body. The gastrocnemius and soleus muscles merge and attach to the back of the calcaneus. During walking it transmits forces 6–8 times body weight, and repeated high loads accumulate microscopic damage in the tendon tissue. The area roughly 2–6 cm above the calcaneal attachment has the lowest blood supply, making it a hotspot for midportion tendinopathy.
Midportion vs. insertional tendinopathy
- Midportion tendinopathy: Pain and fusiform thickening 2–6 cm above the calcaneus. Degenerative changes accumulate in the watershed zone where blood flow is poor.
- Insertional tendinopathy: Pain directly at the back of the calcaneus. May be accompanied by Haglund deformity or a calcaneal bone spur. Friction from the heel counter of shoes is an aggravating factor.
Causes and risk factors
Sudden increases in training volume (more than a 10% weekly increase), poor flexibility of the calf muscles, overpronation (flat feet), and repeated uphill running are major causes. In Korean medicine, this is interpreted as deficiency of the liver and kidneys (肝腎不足) leading to inadequate nourishment of muscles and tendons, with stagnant blood stasis driving tendon degeneration.
Korean medicine treatment
- Acupuncture and electroacupuncture: Needling Kunlun (BL60) and Taixi (KI3) on either side of the Achilles tendon, with electroacupuncture at ashi points around the tendon to increase blood flow.
- Pharmacopuncture: Placental pharmacopuncture is administered around the tendon to induce regeneration of degenerated tendon tissue.
- Herbal medicine: Modified Daebangpung-tang tonifies the liver and kidneys and strengthens muscles and tendons. In the early inflammatory phase, Jakyak-gamcho-tang relieves muscle spasm.
Eccentric exercise
The Alfredson protocol is the standard. Stand on the edge of a step and slowly lower the heel — perform eccentric calf lowering exercises with the knee straight and bent, 15 reps × 3 sets, twice a day. This evidence-based exercise promotes realignment of collagen inside the tendon and restores tendon strength. Perform within a range where you feel mild discomfort, but stop if sharp pain appears.