The flexor tendons are located on the palm side of the fingers and are responsible for flexion (bending) of the fingers and thumb, toward the palm, for grasping and gripping. These tendons are connected to the flexor muscles in the forearm. An injury to the flexor tendons can cause pain and the inability to flex the fingers or thumb- or to grasp with the hand. Common flexor tendon injuries include lacerations and ruptures and are frequently caused by accidents around the home or workplace. Lacerations can sever a tendon and injure other structures, such as the nerves and blood vessels, which run parallel to the tendons. Lacerated tendons will often retract when severed, pulling away from the site of injury and resulting in the tendon slipping away through the tendon pulleys.
The repairing of a retracted tendon requires locating the ends of the tendons and threading them back through the pulleys- before they can be surgically reattached. Ruptures of the tendons are often caused by contact sports such as football or rugby, which require tackling. A common injury is called Jersey finger, which is a rupture of the tendon that is located at the fingertip, also known as the distal interphalangeal joint. It occurs as a result of a sudden hyperextension of an actively flexed finger. Inflammation and spontaneous rupture of the flexor tendons can also be triggered by inflammatory conditions such as rheumatoid arthritis.
Common symptoms of tendon laceration or rupture are general pain, the inability to flex the finger, numbness in the fingertips, tenderness in the finger along the palm side of the hand, pain when the finger is bent, and an inability to bend the joints of the finger. Swelling and bruising may also occur; however, this is not common. Symptoms may also include a limited range of motion. Treatment options include rest, anti-inflammatory and pain-reducing medications, ice compression, and the use of splints. Tendons that have been cut or ruptured require surgery to restore full use to the affected finger. After surgery a cast or splint is needed for up to six weeks to protect the tendon. Healing may take up to three months for full recovery and function of the tendon.