The goal of this clinical trial is to learn about the effectiveness of extracorporeal shockwave(ESWT) combined with platelet-rich plasma(PRP) to treat chronic insertional tendinopathy. The main questions it aims to answer are:

Does ESWT combined with PRP treatment reduce the symptom and improve functional score after treatment? What medical complication do participants have when receive the treatment?

Researchers will compare ESWT combined with PRP to ESWT treatment alone to see if ESWT combined with PRP works to treat chronic insertional tendinopathy.

Participants will:

• Receive ESWT once a week for 4 weeks then receive PRP injection at a week later or ESWT once a week for 4 weeks
• Visit the clinic at 6 weeks, 3 months, 6 months and 1 year after treatment for checkups and record functional score

Inclusion Criteria:

• Diagnosed with insertional Achilles tendinopathy
• Had symptom more than 6 months
• Failed other standard conservative treatment (rest, medication, activity modification, stretching exercise, and heel lift orthosis)

Exclusion Criteria:

• Receive corticosteroid injection at the Achilles insertion
• History of infection around ankle and heel
• Has neurological deficit
• Has a contraindication for ESWT(hemophilia, coagulopathy or foot and ankle malignancy)