Tendons are the white sinew strings that you can easily see in a chicken leg. They are made of collagen and have a very high tensile strength and are inelastic. The job of a tendon is to attach the muscle to the bone and direct the angle of pull of the muscle.
The long tendons of the upper and lower limbs run inside a tube known as the tendon sheath which protects the tendon from rubbing against the bones of the foot and hand. Other tendons in the body have sheaths but what is special about the sheaths of the hand and foot is that they have a mucous membrane which helps the tendon glide smoothly.
Inflammation of the tendon is called Tendonitis
Inflammation of the sheath is called Tenosynovitis or Tenovaginitis.
Tendonopathy is a general term used to describe disease of a tendon.
There are a number of possible causes of tenosynovitis depending on where in the body it occurs. Tenosynovitis of the finger and toe tendons is most commonly caused by repetitive activity and overuse such as running or using hand tools. Other causes can be as a result of a wound infection, insect bite, rheumatoid arthritis, psoriatic arthritis, lupus and diabetes.
Symptoms include pain in the tendon where it crosses over the joint and there may be swelling and redness. The joints operated by the tendon will be stiff (especially in the morning) and there may be loss of strength.
Tenosynovitis in the hand which is left untreated can develop into Stenosing Tenosynovitis aka Trigger Finger. Overuse causes the tendon to become inflamed and swollen so that it “catches” on the tendon sheath where it crosses over a joint. If left untreated this inflammation can develop into a small nodule in the tendon which causes the finger to get stuck in a bent position and then suddenly straighten with a painful pop.
Tendonitis is most commonly caused by overuse (repetitive strain ) or overloading and is particularly prevalent in sporting activities. Inflammation of the tendon is caused by microscopic damage to the fibres of the tendon. The area will be red, swollen and painful to touch. Movements requiring the use of the tendon will be weakened and painful.
Often the cause of the injury can be attributed to lack of warm up before the sporting event or incorrect equipment. For example, Tennis Elbow and Golfers Elbow may be seen as an overuse injury however the grip size of the racquet or club can be a contributing factor. Achillies tendonitis ( a very thick tendon from the back of the heel to the calf) is also an overuse injury that may be related to poor running technique or incorrect footware. Damage to the Achilles when jumping from a height would be seen as an overload injury and is often more serious as macro (as opposed to micro) damage can be the result, such as a tear or rupture to the tendon. Overloading injuries most commonly occur in the gym using dead weights but can also be occupational when repeated heavy lifting is required.
Ice packs or ice dunking and anti-inflammatory medication (as approved by your doctor) should be used as soon as possible to reduce inflammation and swelling.
Any activity involving the use of the tendon should be avoided and the limb should be rested. Occasionally, a sling, splinting or crutches may be necessary.
In more severe injuries your doctor may inject a corticosteroid drug or local anaesthetic into the affected tendon.
Physiotherapy will be required to assess the severity of the condition, advise on splinting and treatments such as ultra-sound, deep frictions, passive stretching, auto-assisted stretching of the tendon, and provide a rehabilitation program to regain strength and flexibility..