Tendon Injury
A tendon is the end section of a muscle where it connects to a bone. When a muscle contracts, a tendon pulls on the point of insertion into a bone to achieve movement in a specific joint.
The main muscles responsible for movement in the fingers and thumb are located in the forearm. All these forearm muscles form long tendons that extend through the wrist and into the hand. The muscles on top of the hand are responsible for lifting the wrist and fingers (extensor tendons) and the muscles on the bottom (palm side) of the hand are responsible for bending the wrist and fingers (flexor tendons).
Cuts or injuries anywhere on the top or bottom side of your fingers, wrist or hand can cause complete or partial injury to one of your tendons. If a tendon is completely cut, the affected finger, thumb or wrist will be unable to straighten or bend.
Tendon injuries typically cannot heal by themselves and mostly need surgical repair. This is due to the fact that tendons are under tension as they connect the muscle to the bone, similar to a rubber band.
Due to this tension in a tendon, the ends of an injured tendon will pull apart when it is torn or completely cut. If a tendon is completely cut is therefore impossible for the tendon to heal on its own and surgical repair will be needed.
Causes
Tendon injuries can be caused by:
- Cuts to the forearm, hand, or fingers.
- Sporting activities that require a lot of arm and hand strength can cause stretching, tearing or tendons pulling off the bone with maximum exertion in a moment.
- Health conditions (like rheumatoid arthritis) can weaken tendons, causing them to tear without warning.
- Internal hardware (like plates and screws inserted when broken bones are fixed) can cause tendons to wear through and tear when moving over sharp edges for an extended period of time.
Symptoms
- Complete inability to bend or straighten one or more joints in the finger, thumb or wrist.
- Pain or tenderness (often radiating down into the forearm) when attempting to bend or straighten the finger, thumb or wrist.
- Swelling and bruising around injured area and up to the elbow.
Conservative management
Most tendon injuries require surgical intervention, but occasionally tendons may be partially cut or torn. This might cause pain, swelling and partial loss of movement in the wrist, thumb or fingers. These types of tears can be difficult to diagnose, but can sometimes heal without surgical intervention. However, even in in cases where tendons are partially cut, surgical repair may sometimes be necessary.
The only tendon injury known to heal without surgical intervention is called a “mallet finger”. This is when the terminal part of the extensor tendon on the tip of a finger tears off, causing the tip of the finger to ‘hang’. In this case a finger splint may be manufactured to position the finger in extension. The splint is worn for 6-8 weeks to allow the tendon to heal (read more about this condition under ‘Mallet fingers’)
Surgical management
If a tendon has been completely cut or torn, it is crucial that the tendon must be repaired as soon as possible. If you wait too long, the two opposite ends of the tendon can retract and shorten. This will then require the surgeon to graft an extra piece of tendon, taken from somewhere else in the body, to make the two ends meet.
During tendon repair surgery the following steps usually happen:
- At least one cut is made through the skin (sometimes more) in the area of the injured tendon. If there is already a cut due to the injury, the surgeon will use the existing cut, but might extend it to allow him to find the injured tendon.
- Damaged or dead tendon tissue will be removed.
- The torn ends of the tendon will be sewn back together with stitches using special suturing
The skin is sewn back together with stitches, covered with dressings, and a post-operative cast is applied to the hand.
Post-operative management
- You will be immobilized in the post-operative cast for 8 – 14 days after surgery. Your stitches may be either dissolvable or the doctor or therapist will remove them after 10 – 14 days.
- After 10 – 14 days your post-operative cast will be removed and you will be seen by the hand therapist for a splint. This splint is made of thermoplastic splinting material and will be custom made to fit your hand. The shape of the splint is positioned specifically to rest your hand and wrist in a way that reduces tension on the repaired tendon. It also prevents and allows certain movements.
- You will have to wear the splint for six weeks after surgery and attend regular therapy appointments during this time.
- After six weeks the splint can usually be removed and patients can start using their hands in daily activities. Return to sports and heavy use of hand is however only safe from 10 – 12 weeks after surgery.
Aims of hand therapy
Hand therapy is necessary for the functional rehabilitation of a hand and/or forearm that suffered a flexor tendon injury and was surgically repaired. Aims of hand therapy include:
- Splinting the hand in the correct position. The splint might be adjusted weekly as your hand improves. The splint will typically reach from your fingertips, over your wrist and end mid-way down your forearm (this will however depend on your level of injury).
- Management of swelling and wound care.
- Gradual exercises program to prevent stiffness and improve tendon gliding of the injured tendons, without putting too much strain on them.
- Management of pain.
- Scar management.
- Improvement of function and grip strength as healing allows.
After surgery patients will have to follow up in hand therapy for at least six to eight weeks. Follow up appointments may vary from person to person depending on tissue healing and progress made in therapy. The complete recovery after tendon surgery can take anywhere between 12 weeks and one year.
*The above text is for information purposes only and should not be seen as health advice. Please consult with your medical practitioner should you require health advice or medical treatment.