What Are the Differences Between Tendonitis and Arthritis?

Tendonitis

• Tendonitis is the inflammation of the tendon.
• A tendon is a connective tissue band or cord-like structure that connects a muscle to a bone.

Arthritis

• Arthritis is the inflammation of one or more joints in the body.
• Joints are sites where the bones meet and movement occurs.
• Some joints, however, may be immobile, such as the joints (called sutures) between your skull bones.

The main causes of tendonitis include:

• Sports injuries
• Repetitive movements
• Poor posture
• Arthritis
• Diabetes and other metabolic diseases
• Infections 
• Congenital joint or bone abnormalities
• Kidney disease
• Older age
• Side effects of medications (rare) such as fluoroquinolones and statins

The major causes of arthritis vary depending on the type. There are more than 100 types of arthritis and related conditions.

Causes of some of the main types include:

• Osteoarthritis: Occurs due to the wear and tear of the cartilage that cushions the joint. This may be caused by factors such as aging, obesity, or joint overuse.
• Rheumatoid arthritis: A type of chronic inflammatory condition in which the body’s immune system attacks its joints along with other tissues and organs. Certain factors such as genetics, female gender, obesity, and smoking may increase the risk.
• Psoriatic arthritis: Occurs in about 30 percent of people with psoriasis. The abnormal immune response that causes skin rashes also attacks the joint causing arthritis.
• Gout: A type of metabolic arthritis in which abnormal deposition of uric acid crystals in the joints causes joint inflammation.

Other causes of arthritis may include infection (septic arthritis) and joint injury.

The main symptom is pain at and around the affected site. There may also be swelling of the area, and the part may be tender to touch.

• The pain gets typically aggravated on movement and gets relieved after rest and treatment.
• Pain may slowly build up in intensity or may be a sharp and severe type.
• Symptoms may come and go during the course of the disease.

Symptoms may vary depending on the type of arthritis. Characteristic arthritis symptoms include joint pain and swelling.

• The skin over the affected joint may appear red and the movement may be painful. 
• There may be a grating sensation on moving the affected joint.
• Joint stiffness or reduced range of motion is also commonly seen.

Treatment mainly involves:

• Resting the affected limb
• Application of cold packs
• Avoiding repeated movements or activities that make symptoms worse
• Over-the-counter pain medications such as ibuprofen and naproxen
• Corticosteroids
• Physical therapy
• Surgery (may be needed if conservative treatment fails)

The treatment depends on the severity and cause of arthritis. It generally includes:

• Medications to reduce pain and inflammation such as nonsteroidal anti-inflammatory drugs and corticosteroids
• Topical creams or ointments (counterirritants)
• Disease-modifying antirheumatic drugs or biological agents 
• Physical therapy
• Surgery may include joint repair, replacement, or fusion

Arthritis and tendonitis may be difficult to identify based on symptoms alone. Generally, tendonitis causes sudden or acute pain, whereas, in the case of arthritis, the pain is often chronic in nature.

Your doctor will take your detailed history, perform a physical examination and order certain imaging tests or blood work to identify the cause of your symptoms (tendonitis or arthritis).