Tendinitis, also known as tendonitis, is the inflammation of a tendon. Tendinitis is a type of tendinopathy - a disease of the tendon. Tendinosis is similar to tendinitis, but requires different treatment. Tendinitis refers to larger-scale acute (sudden, short-term) injuries with inflammation.
Usually tendinitis is referred to by the body part involved, for example, Achilles tendinitis which affects the Achilles tendon, or patellar tendinitis which affects the patellar tendon (jumper's knee). Tendinitis can occur in various other parts of the body, including the elbow, wrist, finger, or thigh. It is caused by overusing a tendon or injuring it, as may happen during sport.
Tendinitis can affect people of any age, but is more common among adults who do a lot of sports. Elderly individuals are also susceptible to tendinitis because our tendons tend to lose their elasticity and become weaker as we get older.
Some common lay terms for tendinitis include:
- Golfer's elbow
- Jumper's knee
- Pitcher's shoulder
- Swimmer's shoulder
- Tennis elbow
What are tendons?
A tendon is tissue which attaches muscle to bone. It is flexible, tough and fibrous and is capable of withstanding tension. A ligament extends from bone to bone at a joint, while a tendon extends from muscle to bone. Tendons and muscles work together and can only exert a pulling force. Although tendons and ligaments are tough and fibrous, they are referred to as soft tissue, because of their common comparison to bone or cartilage.
The Latin word tendere and the Greek word teinein mean "to stretch".
Inflamed tendons (tendinitis) are more likely to get ruptured. If the sheath around the tendon becomes inflamed, rather than the tendon itself, the condition is called tenosynovitis. People can have tendinitis and tenosynovitis simultaneously.
Symptoms of tendinitis
A symptom is something the patient feels and reports, while a sign is something other people, such as the doctor detect. For example, pain may be a symptom while a rash may be a sign.
Tendinitis symptoms occur where the tendon attaches to a bone; and usually include:
- Pain - if the affected area is moved the pain worsens
- A feeling that the tendon is crackling or grating as it moves. This sensation is more common on examination.
- Swelling in the affected area
- The affected area may be hot and red
- A lump that develops along the tendon
If there is a rupture a gap may be felt in the line of the tendon and movement will be very difficult.
Causes of tendinitis
The condition is commonly caused by repetition of a particular movement over time. It can also be caused by a sudden injury. In the majority of cases, tendinitis develops in people whose jobs or hobbies involve repetitive movements; aggravating the tendons.
A tear in the tendon caused by an injury may cause swelling (inflammation).
Risk factors for tendinitis
A risk factor is something which increases the likelihood of developing a condition or disease. For example, obesity significantly raises the risk of developing diabetes type 2. Therefore, obesity is a risk factor for diabetes type 2.
Age - tendons become less flexible as we get older, making them more susceptible to injury.
Some jobs - if a person's job includes the following tasks their risk of developing tendinitis is higher:
- Repetitive movements
- Awkward positions
- Reaching overhead frequently
- Forceful exertion
Tennis elbow is caused by overuse of the forearm muscles.
Sports - people who practice certain sports regularly are more likely to develop tendinitis, especially sports that involve repetitive movements, including:
Diabetes - people with diabetes have higher risk of developing tendinitis. Experts are not sure why.
Rheumatoid arthritis - people with rheumatoid arthritis have a higher risk of developing tenosynovitis (when the sheath surrounding the tendon is inflamed).
On the next page we look at how tendinitis is diagnosed, the available treatments and how tendinitis can be prevented.