Tendonitis: Causes and Treatment

September 7, 2021

Tendonitis occurs when any of the body’s tendons, the strong and elastic cords of tissue that connect bone and muscle,1 becomes inflamed or irritated, or suffers a microscopic tear. Also known as tendinopathy, its symptoms typically include pain, swelling, and warmth at the site of the injury and the surrounding tissue.2 Common areas for tendonitis include the wrist, elbow, shoulder, knee, and ankle, and some conditions, such as “swimmer’s shoulder” and “tennis elbow,” are named for the activity and site associated with a particular type of tendonitis. This condition is most common in adults over 40, whose tendons are less elastic and tear more easily.3 Physical therapy is a key treatment modality for tendonitis.

            Tendonitis has traditionally been attributed to the overuse of certain muscles and repetitive motion that puts stress on individual tendons. For example, a correlation between running mileage and tendonitis in runners has been established,4 as well as a positive relationship between increased playing time and tennis elbow.5 However, as Almekinders and Temple note,6 many studies point to intrinsic factors that may contribute to the development of tendonitis. Decreased vascular supply to tendons, especially to the supraspinatus tendon, has been shown to be a predisposition to tendonitis.7 Other intrinsic factors that may induce tendonitis include eccentric contractions of the muscle-tendon unit8 and anatomical variation in alignment and range of motion that places additional mechanical stress on tendons,9 though studies attempting to support these theories have only been retrospective in nature.

            Treatment for tendonitis typically seeks to relieve pain and simultaneously rest the offending tendon and its associated muscles. Over-the-counter pain relievers are often recommended in conjunction with the classic RICE (rest, ice, compression, elevation) regimen for soft tissue injuries.10 Depending on the severity and location of tendonitis, other treatment options can include immobilization, application of heat, corticosteroid injections, and, rarely, orthopedic surgery.3

            Physical therapy is an additional option available to healthcare professionals seeking to treat tendonitis. Manual therapy, such as massages and eccentric strengthening, and other techniques like dry needling can reduce muscle tightness and promote healing.  Mayer et al.11 conducted a study in which runners with Achilles tendinopathy were either treated with physical therapy for four weeks, wore custom insoles, or were part of a control group with neither. Physical therapy consisted of ice, pulsed ultrasound, and deep friction massages. Runners in the physical therapy group (and, to a nearly identical degree, those in the insole group) reported significant pain reduction and higher eccentric plantar flexion torque, a measure of the flexibility of the muscles of the foot.

            In addition to effectively treating typical tendonitis, physical therapy has been shown to relieve pain and increase mobility in those with calcifying tendonitis (CT), a painful condition characterized by calcium deposits in the rotator cuff tendon. In a 2015 study,12 researchers treated 50 CT patients with kinesiotherapy and various types of electrotherapy. Patients were asked to indicate their level of pain on the visual analog scale before and after treatment. Nearly all patients reported significant decreases in pain, which helps to establish the benefits of physical therapy in treating tendonitis but does not indicate which method of physical therapy is more effective. Regardless, physical therapy is certainly a useful treatment for tendonitis and its applications to the inflammatory condition should be studied further.


1. “Tendonitis.” Johns Hopkins Medicine, www.hopkinsmedicine.org/health/conditions-and-diseases/tendonitis.

2. “Tendonitis.” Harvard Health, 15 Dec. 2014, www.health.harvard.edu/diseases-and-conditions/tendonitis.

3. “Tendonitis (Tendinitis): Causes, Symptoms & Treatments.” Hospital for Special Surgery, www.hss.edu/condition-list_tendonitis.asp.

4. Lysholm, J., and J. Wiklander. “Injuries in Runners.” The American Journal of Sports Medicine, vol. 15, no. 2, 1987, pp. 168–171., doi:10.1177/036354658701500213.

5. Gruchow, H. W., and D. Pelletier. “An Epidemiologic Study of Tennis Elbow.” The American Journal of Sports Medicine, vol. 7, no. 4, 1979, pp. 234–238., doi:10.1177/036354657900700405.

6. Almekinders, L. C., and J. D. Temple. “Etiology, Diagnosis, and Treatment of Tendonitis: An Analysis of the Literature.” Medicine & Science in Sports & Exercise, vol. 30, no. 8, 1998, pp. 1183–1190., doi:10.1097/00005768-199808000-00001.

7. Lohr, J. F., and H. K. Uhthoff. “The Microvascular Pattern of the Supraspinatus Tendon.” Clinical Orthopaedics and Related Research, no. 254, May 1990, doi:10.1097/00003086-199005000-00005.

8. Stanish, W. D., et al. “Eccentric Exercise in Chronic Tendinitis.” Clinical Orthopaedics and Related Research, vol. 65, no. 208, July 1986, doi:10.1097/00003086-198607000-00014.

9. Messier, S. P., and K. A. Pittala. “Etiologic Factors Associated with SELECTED Running Injuries.” Medicine & Science in Sports & Exercise, vol. 20, no. 5, Oct. 1988, doi:10.1249/00005768-198810000-00012.

10. “The Best Ways to Treat, Prevent Tendonitis.” Health Encyclopedia – University of Rochester Medical Center, www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=1&contentid=739.

11. Mayer, F., et al. “Effects of Short-Term Treatment Strategies over 4 Weeks in Achilles Tendinopathy.” British Journal of Sports Medicine, vol. 41, no. 7, 2007, doi:10.1136/bjsm.2006.031732.

12. Fernández-Cuadros, M. Edgar, and O. Susana Pérez-Moro. “Calcifying Tendonitis of the Shoulder: Risk Factors and Effectiveness of Physical Therapy.” Occupational Medicine & Health Affairs, vol. 03, no. 06, 2015, doi:10.4172/2329-6879.1000220.