This study is designed to compare the treatment of 2 groups in patients with Achilles tendinopathy: autologous tenocytes injection in combination with exercises versus saline injection in combination with exercises

Overuse injury of the Achilles tendon is a common entity. When the exact origin of tendon pain is unclear, the term tendinopathy is preferred. Most accepted treatment at this moment is an eccentric exercise programme, according to the Dutch guidelines. However, a recent systematic review on the effectiveness of eccentric exercises to treat lower extremity tendinoses concluded that it is unclear whether eccentric exercises are more effective than other forms of treatment. Recent studies described new treatment strategies in tendinopathies, such as the use autologous Tenocyte Implantation (ATI). This treatment option can participate actively in tissue repair processes on cell level. The only published clinical pilot study in tendon research reported 60% improvement in all scores after 6 months follow-up.

Inclusion Criteria:

• Pain on palpation 2-7 cm proximal from the tendon insertion ("midportion")
• Symptoms > 2 months
• Age 18-55 years

Exclusion Criteria:

• Clinical suspicion of insertional disorders , Achilles tendon rupture, plantar flexor tenosynovitis, sural nerve pathology, peroneal subluxation
• Condition of the Achilles tendon caused by medications such as quinolones and statins
• Known to have the following disorders: spondylarthropathy, gout, hyperlipidemia, rheumatoid arthritis and sarcoidosis.
• Antibiotics allergy (aminoglycoside group)
• A condition that prevents the patients from executing an active rehabilitation programme
• Patient has received an injection for this injury
• Patient has received surgical intervention for this injury
• Patient has already one site (left or right) included in this study
• Patient does not wish, for whatever reason, to undergo one of the two treatments
• Known pregnancy
• Nursing women