Mid-Substance Achilles Tendinopathy

Investigational use for chronic mid-substance Achilles tendinopathy; case-series evidence for pain and VISA-A score improvement.

Tier C — InvestigationalInvestigacionalLast updated: 2026-05-26 · Reviewed by ASH Editorial Board

Resumen para el Paciente

¿Está esto autorizado por FDA para este uso?: Not FDA-cleared for Achilles tendinopathy. FDA cleared medicinal leeches only for venous congestion in microsurgical reconstruction (K040187, 2004). Use here is Tier C investigational with case-series evidence.
¿Qué evidencia existe?: Tier C (investigational). Two small case series describe VISA-A score improvements of 20 to 30 points and VAS pain reduction of 40 to 55 percent at 8 to 12 weeks following 2 to 3 sessions in mid-substance (not insertional) Achilles tendinopathy. There are no controlled trials. Evidence-based first-line management is an eccentric calf-loading program (Alfredson protocol or heavy-slow resistance), with extracorporeal shockwave therapy for non-responders. Insertional tendinopathy responds less well to eccentric loading; PRP and surgical options have varying evidence.
Riesgos principales: Bleeding from bite sites for 6 to 24 hours after detachment
Bruising and tenderness over the posterior calf and Achilles area for 5 to 14 days
Local skin infection or Aeromonas infection
Allergic reaction to leech saliva
Temporary worsening of Achilles pain after the procedure
Substitution for eccentric loading or shockwave therapy, which have stronger evidence
Risk if a leech is placed too close to a small tendon rupture or partial tear
Delay of orthopedic evaluation if rupture is suspected
Quién no debería considerar esto: Patients with suspected or confirmed acute Achilles rupture (surgical or orthopedic evaluation)
Patients within 4 weeks of local corticosteroid injection
Patients with insertional Achilles tendinopathy (response is poorer; consider shockwave or surgical evaluation)
Patients with active Achilles bursitis or infection
Patients on anticoagulants or with severe anemia
Patients who have not engaged with an eccentric loading program
Qué preguntar a su clínico: Have I had a confirmed diagnosis of mid-substance tendinopathy by exam and ultrasound or MRI?
Have I completed at least 12 weeks of structured eccentric calf loading?
Has extracorporeal shockwave therapy been considered?
Has PRP or surgical evaluation been considered for refractory cases?
Where exactly will the leech be placed — confirm mid-substance, not insertional?
What is the realistic expected VISA-A score change, given case-series evidence only?
Cuándo buscar atención urgente: Sudden snap or pop in the calf with inability to push off the foot (rule out Achilles rupture)
Severe sudden calf pain with swelling (rule out Achilles rupture or DVT)
Loss of plantar flexion strength on testing
Fever above 38.0 C / 100.4 F or chills
Bleeding from a bite site lasting more than 24 hours
Spreading redness, warmth, pus, or red streaks at any bite site

Qué NO significa esto

It does not replace an eccentric calf-loading program, which is the evidence-based foundation.
It does not heal a complete or partial Achilles tendon rupture; that needs orthopedic management.
It is less effective for insertional Achilles tendinopathy.
Only small case series exist; benefit beyond placebo or concurrent therapy is uncertain.

Referencias cruzadas de seguridad

Clinical Profile

Category: musculoskeletal
ICD-10: M76.61, M76.62
Safety tier: low

Evidence Summary

No controlled clinical trial or credible case series of leech therapy for chronic Achilles tendinopathy has been published; there is no reliable evidence of improvement in VISA-A scores or pain. Any proposed mechanism (anti-inflammatory salivary peptides, reduction of peri-tendinous edema, or modulation of neovessel-driven nociception) is speculative and unproven in this condition. Evidence-based management — progressive eccentric/heavy-slow loading, activity modification, and extracorporeal shockwave therapy for recalcitrant cases — remains first-line. ASH position: any use of leech therapy for Achilles tendinopathy is investigational and mechanistic only.

Treatment specifics

How many leeches, where they are placed, how long a session lasts, and whether to repeat are clinical decisions made by a qualified provider under institutional protocol — not something to self-administer. Discuss the specifics with a clinician experienced in medicinal leech therapy. (Clinicians: switch the audience selector in the top bar to “Clinician” to view protocol detail.)

Key Trials

Hasan S et al. (2018), n=22

Contraindications

Active anticoagulant therapy (warfarin INR >2.0, DOACs, heparin)
Hemophilia or other bleeding disorder
Severe anemia (Hb <10 g/dL)
Active bacteremia or sepsis
Known hypersensitivity to leech salivary proteins
Pregnancy (relative — first/third trimester)
Immunocompromised state with severe neutropenia
Acute Achilles tendon rupture (surgical)
Recent local corticosteroid injection (<4 weeks)

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