Achilles Tendinopathy

Blausen Medical · Wikimedia Commons · CC BY 3.0

Achilles tendinopathy is a degenerative condition of the Achilles tendon — the largest and strongest tendon in the body — rather than a classic inflammatory "tendinitis." Repetitive overloading causes intratendinous collagen disorganization (tendinosis) at either the mid-portion (2–7 cm above the heel, the "watershed zone" with poorest blood supply) or the insertion at the calcaneus (insertional tendinopathy). Runners are disproportionately affected.

Symptoms include aching posterior heel pain, tendon thickening, and morning stiffness that warms up with activity. A fusiform nodule at the mid-tendon is characteristic of mid-portion tendinopathy.

Clinical diagnosis. The Royal London Hospital test — tenderness at mid-tendon that decreases with passive dorsiflexion — helps distinguish mid-portion from insertional disease. Ultrasound confirms tendon thickening, hypoechoic change (degeneration), and neovascularization. MRI provides better soft-tissue detail for surgical planning.

1. Physical therapy

   Heavy slow resistance (HSR) program, shockwave therapy adjunct.

2. Extracorporeal shock wave therapy

   Effective for both mid-portion and insertional tendinopathy, particularly in chronic cases.

3. PRP injection

   Evidence supports PRP over corticosteroid (which risks rupture); may be combined with needling/tenotomy.

Surgery is considered after 3–6 months of eccentric loading and adjunct therapies have failed.

External patient-education references and related OSI pages for additional background:

• Britannica — Tendinitis
• Britannica — Ankle (anatomy)
• AAOS OrthoInfo — patient education library
• OSI glossary — orthopedic terminology in plain language