Flexor pronator tendon origin, severe tendinosos with 17 x 9 mm partial thickness instrasubstance tear. How can this be repaired. Chronic for 2 yrs?

Tendon injury. Injuries to bones, tendons, & ligaments are best dealt with by orthopedic surgeons or hand surgeons (if applicable). They can evaluate status of injury, offer options for treatment, including surgery if indicated.