64 Tendinitis

Tendon

Tendons are bands of dense regular connective tissue composed of collagen, proteoglycans, and tenocytes (elongated fibroblast type cells) that connect muscle to bone.  Muscle is wrapped in 3 layers of connective tissue, the endomysium surrounding each myofiber (skeletal muscle cells), perimysium surrounding each bundle or fascicle of myofibers, and epimysium surrounding bundles of fascicles that make-up the muscle.  The epimysium (or fascia) is composed of dense irregular connective tissue that extends to form the tendon that anchors the muscle to bones.  The collagen within the tendon penetrates into the bone in the form of Sharpey’s fibers giving strength and support.  The elasticity of tendons allow for tendons to function not only in withstanding forces but also by acting as springs (see Plantar Fascia section) which makes walking and running more energy efficient.  Tendon stretchiness also allows muscles to shorten and generate force in isometric contractions.

Interestingly, sinew (fibrous tissues such as tendons or ligaments) was used historically by humans to create rope, thread, and bows taking advantage of the flexible, durable, and strong mechanical properties of tendons and ligaments.

Tendonitis

Tendonitis by definition is characterized by inflammation of the tendon, often a result of an acute or chronic condition.  Tendinitis may be associated with tendinosis, which is defined as tendon degeneration.  The suffix -osis refers to a degenerative condition. The term tendinopathy may be used generally to indicate any problem with the tendon, with the suffix -pathy derived from a Greek word meaning disease or disorder.

Risk Factors and Prevention – Tendonitis

The most common causes of tendonitis is due to over-use (e.g., tennis, golf, running) and the most common tendons affected include:  tendons of the rotator cuff muscles of the shoulder (e..g, supraspinatus), biceps tendons, tendons in the elbow and wrist, the patellar tendon and iliotibial band at the knee, and the Achilles tendon of the heel.

Examples:

Lateral epicondylitis is most commonly caused by racquet sports or manual labour.

Medial epicondylitis is associated with golfing, baseball pitching, bowling and manual labour.

Rotator cuff tendinopathy often occurs with repetitive overhead arm movements (e.g., swimming, painting, throwing)

Patellar tendinopathy is associated with running and jumping and can be experienced by runners, and volleyball and basketball players.

Iliotibial band syndrome and Achilles tendinopathy are associated with participating in football, dance, cycling, running

Prevention of tendonitis involves gradually ramping up exercise and activity levels over time, as well as utilizing supportive shoes and equipment (e.g., properly strung tennis racquets)

Pathogenesis – Tendonitis

Tendons that experience trauma, which can lead to tears that range in size from microtears to larger tears.  The affected collagen, proteoglycans, associated vasculature, neurons, and cells such as tenocytes are able to regenerate, though full recovery depends on the extent of damage, overall health and age of individual, as well as treatment and rehabilitative strategies.  Complications involving dystrophic calcification which impede healing and can lead to impaired function.  Excessive scarring can lead to tendon shortening and loss of range of motion (adhesive capsulitis also known as frozen shoulder).

*Note:  Unfortunately, calcium deposits can also occur spontaneously (without prior trauma to the tendon), in idiopathic calcifying tendinitis.

Signs and Symptoms – Tendonitis

Signs and symptoms include everything expected with an inflammatory condition.  Locally, there will be swelling as well as pain, and possibly redness, warmth and impaired performance.

Complications include tendon weakening, tendon rupture and adhesive capsulitis (i.e., frozen shoulder).

Diagnostic Tests – Tendonitis

Physical examinations and imaging (e.g., x-ray, ultrasound and MRI) are useful in assessing injuries and the presence of calcium deposits.

Treatment – Tendonitis

Typical treatments involve PRICE (Protection with splinting or immobilization; Rest, Ice, Compression and Elevation), analgesic and anti-inflammatories (e.g., NSAIDs or topical non-steroidal anti-inflammatories), possibly corticosteroid injections and/or surgery.  New treatments are being developed all of the time, and there has been some success in treating calcific deposits with ESWT (extracorporeal shock wave therapy), TENS (transcutaneous electrical nerve stimulation), ultrasound-guided needling (breaking up calcium with needle), and barbotage (saline injection/aspiration washes).

As always, each treatment has its pros, cons, and risks associated (e.g. ESWT is associated with risk of developing hematomas).

Rehabilitation typically involves a prescribed progression of stretching and strengthening activities to maintain and restore range motion, strength and activity levels.

Summary

• Carpal Tunnel Syndrome (CTS) is a repetitive strain injury.
• Inflammation and damage can occur if ergonomics aren’t adjusted.
• Scar tissue buildup can increase pressure on nerves, causing pain, tingling, and weakness.
• Joint damage can increase the risk of developing osteoarthritis in the future.
• Preventing CTS involves adjusting keyboard ergonomics and ensuring proper movement mechanics.
• Tendinitis, indicated by “-itis,” involves tendon inflammation and can be caused by activities like tennis, hockey, painting, keyboard use, running, and massage.
• Tendinopathy: disease of tendons
• Examples: Tennis elbow (lateral side), Golfer’s elbow (medial side)
• Pain due to micro-tears in tendon, bleeding, inflammation
• Signs and symptoms: pain on movement
• Treatment: RICE, anti-inflammatories, physical therapy, massage, rest
• Treatment: RICE, fluid aspiration, antibiotics for infection
• PRICE (Protection, Rest, Ice, Compression, Elevation) can help manage symptoms and prevent excessive scar tissue formation.
• Arthroscopy allows surgeons to view and repair joint injuries, such as ligament tears or meniscus tears.
• Viewing scope and surgical instruments for repairing damaged tissue
• Arthrography: X-ray or CT scan to view joint damage
• Radio-dense dye (iodine) for X-ray, MRI contrast medium for MRI
• Prevention: proper warm-up, technique, equipment, gradual activity increase
• Bursitis: often in knees from prolonged kneeling

Rehab:

• Tennis elbow:
  • Similar stretching regimen before adding weights.
  • Gradual progression from weight-free to weighted stretches.
• Importance of prescribed exercises to prevent conditions like frozen shoulder.
• Exercises for other conditions: golf, pre-patellar bursitis.
• Challenge in replicating tendons synthetically due to high mechanical stresses.
• Rheumatic diseases: affect joints, tendons, ligaments, bones, or muscles.