High-Volume Image-Guided Injection in Chronic Midportion Achilles Tendinopathy

Inclusion Criteria: 1. Age 18-70 years. 2. Clinical diagnosis of chronic midportion Achilles tendinopathy: Painful swelling of the Achilles tendon, 2-7 cm proximal to it's calcaneal insertion. 3. Non-response to exercise program for 6 weeks. 4. Painful Achilles tendon for more than 2 months. 5. Neovascularisation is present on Power Doppler Ultrasonography examination Exclusion Criteria: 1. Clinical suspicion of insertional disorders (pain at the site of the insertion of the Achilles tendon on the calcaneum) 2. Clinical suspicion of an Achilles tendon rupture (Thompson test abnormal and palpable "gap") 3. Clinical suspicion of plantar flexor tenosynovitis (posteromedial pain when the toes are plantar flexed against resistance) 4. Clinical suspicion of n.suralis pathology (sensitive disorder in the area of the sural nerve) 5. Clinical suspicion of peroneal subluxation (visible luxation of the mm. Peronea spot in combination with localized pain) 6. Suspicion of internal disorders: spondylarthropathy, gout, hyperlipidemia, Rheumatoid Arthritis and sarcoidosis. 7. Condition that prevents the patients from executing an active exercise program 8. Recently prescribed drugs (within 2 years) with a putative effect on symptoms and tendon healing (quinolone antibiotics, corticosteroids). 9. Previous Achilles tendon rupture. 10. Patient has received surgical intervention for his injury. 11. Patient does not wish, for whatever reason, to undergo one of the two treatments 12. A medical condition that would affect safety of injection (e.g. peripheral vascular disease, use of anticoagulant medication) 13. Known presence of a pregnancy 14. Condition of the Achilles tendon caused by medications (arising in relation to moment of intake), such as quinolones and statins 15. Inability to give informed consent. 16. Participation in other concomitant treatment programs. 17. Patient has already one side included in this study. 18. Allergy for lidocain.