Flexor tendon injuries

What are flexor tendons?

Your flexor tendons are strong fibrous cords connecting the muscles in your forearm to your finger and thumb bones. They enable you to bend your fingers and grip objects. Each finger has two of these tendons, while your thumb has one. These structures run through protective sheaths at your wrist and along your fingers.

These tendons lie particularly close to the skin on your palm and at the creases of your fingers, making them susceptible to cuts from sharp objects. Occasionally, forceful pulling injuries can tear a tendon away from where it attaches to bone.

    • A laceration on your palm, wrist, or finger

    • Difficulty or inability to curl the affected finger

    • The injured finger appears more extended compared to your other fingers

    • Discomfort when trying to make a fist

    • Loss of sensation in the finger (indicating possible nerve damage alongside the tendon injury)

    Proper evaluation is essential. I'll assess each tendon's function to determine whether repair is necessary. Imaging such as x-rays may be required if the injury involved glass, and sometimes ultrasound or MRI scanning helps clarify the diagnosis.

  • Surgery

    Severed tendons won't reconnect naturally. The muscle tension pulls the torn ends apart, often creating a substantial gap. Surgical intervention is necessary to restore finger function.

    During the procedure:

    • You'll receive either general anesthesia or a regional block that numbs your entire arm

    • I'll extend the original wound to access and retrieve both tendon ends

    • The tendon is sutured back together

    • Your hand is placed in a protective splint with gentle flexion at the wrist and fingers to safeguard the repair

    Rehabilitation with hand therapy

    Post-operative therapy is essential to your recovery - equally important as the surgical repair itself. Your hand therapist will transition you from the initial splint to a custom lightweight brace within the first week and initiate a specific movement protocol.

    This specialised program keeps the repaired tendon mobile within its sheath, preventing scar tissue formation while avoiding excessive stress that could rupture the repair. Close adherence to your therapist's guidance is vital.

    What to expect during recovery

    • Protective splinting continues for approximately 6-8 weeks

    • Progressive return to normal activities begins after splint discontinuation

    • Complete tendon healing requires roughly 3 months

    • Gradual functional improvement may continue for half a year

  • These injuries are complex. The substantial forces transmitted through flexor tendons and their propensity to form restrictive scar tissue mean that even optimal surgical technique combined with diligent therapy may not restore complete finger motion. Nevertheless, surgical repair offers significantly better outcomes than leaving the injury unaddressed.

    Repair failure

    The greatest risk occurs during early healing when the tendon tissue is weakest. Some patients describe feeling or hearing a snap, while others simply notice reduced finger mobility. Contact me or your therapist without delay if you're concerned about repair failure - timing is critical, as re-repair becomes increasingly difficult after several days.

    Scar tissue formation

    The tendon may develop adhesions to surrounding structures, restricting its normal gliding motion. Extended therapy may resolve this, and in select cases, surgical release of the adhesions can restore better movement, though achieving full range of motion remains challenging.

Prompt specialist evaluation is important following hand lacerations. Please seek assessment quickly if you've sustained this type of injury.