Surgical Treatment of Intratendinous Heterotopic Ossification of Flexor Digitorum Superficialis Causing Stiff Flexion Contracture of the Ring Finger

Case: A 19-year-old student developed a stiff flexion contracture of the proximal interphalangeal joint of the ring finger due to intratendinous heterotopic ossification (HO) of the flexor digitorum superficialis (FDS) tendon after a head injury. Surgical excision of the ossified segment and soft-tissue release was performed. Postoperative rehabilitation included structured hand therapy. At the 1-year follow-up, the patient demonstrated functional range of motion (20°-110°) without recurrence Conclusion: Intratendinous HO of the FDS tendon is rare and can severely affect hand function. Early diagnosis, surgical excision, and dedicated rehabilitation are essential for restoring motion and preventing long-term disability in such cases.