Abstract Background: There are many techniques of flexor tendon repair, which comprise of a core suture of different configu-rations with or without an epitendinous running stitch. Several studies have compared these methods with different results. Ultrasonography is being used more in the management of tendon injuries, however few studies have used it to compare repair techniques. Aim of Study: The study aimed to use ultrasonography (US) to compare 2-strand and 4-strand core sutures in flexor tendon repair, in addition to functional outcome. Patients and Methods: This was a randomized prospective comparative study of 40 patients with flexor tendon injuries. They were assigned to 2 groups -- Group A had a 4-strand cruciate core suture, while Group B received a 2-strand modified Kessler repair. Patients started an early controlled active mobilization protocol and were assessed by ultrasonog-raphy and clinical examination. Results: A total of 64 tendons were repaired in 50 fingers, equally divided among both groups where their demographics were comparable. Ultrasonographic assessment showed less tendon gap measurements with 4-strand repair, and adhesions were not significantly different. Most patients had good range of motion, and this was not related to adhesion formation. There was no significant difference between both groups in terms of complications. Conclusion: Ultrasonography is a useful method to com-pare different types of tendon repair. Four-strand core sutures had less gap formation, with no significant difference in adhesions or complication rates, compared to 2-strand repairs.