One hundred patients with chronic midportion Achilles tendinopathy were randomized to receive either exercise therapy combined with ultrasonography-guided corticosteroid injection (n=48) or exercise therapy with placebo injection (n=52). The primary outcome was improvement in the Victorian Institute of Sport Assessment–Achilles (VISA-A) score at 6 months. Secondary outcomes included tendon thickness, pain during activity and in the morning (measured by VAS), and global assessment of treatment response. Outcomes were assessed at baseline and 1, 2, 3, 6, 12, and 24 months. Overall, the results revealed that the corticosteroid group showed a significantly greater improvement in VISA-A scores at 6 months, accompanied by improved tendon morphology and early symptom relief, with no increase in adverse events. These findings suggest corticosteroid injections combined with exercise therapy may be a more effective treatment strategy for long-standing Achilles tendinopathy.