Alex Simotas, MD

Hospital for Special Surgery
Board Certified Physiatrist
Specializing In Spine & Sports Medicine

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Tendonitis, Bursitis & Arthritis

This article will briefly discuss three common forms of musculoskeletal disorders referred to as tendonitis, bursitis, and arthritis. The –itis ending of each of these terms implies a process of inflammation. Thus tendon-itis is a term used to describe inflammation associated with a tendon. By contrast arthritis refers to inflammation of a joint and bursitis refers to inflammations in a bursa.

Changing Perspectives: From “itis” to “osis

Osis is the ending added to confer age related wear and tear.  In reality most tendonitis and arthritis appears to periods of aggravation or excess stress that occur on tendons or joints that undergone some aging changes.  As a result the term “tendonosis” and “arthrosis” have in most instances, replaced the terms tendonitis and arthritis.


ABOUT TENDONITIS (or Tendonosis)

Tendons are rope-like tissues that connect muscles to bone. Inflammation may exist within the substance of the tendon itself, in the soft tissue just outside of the tendon (often referred to as peritendonitis) or in a sleeve through which the tendon slides back and forth (tenosynovitis).

One of the most common types of tendonitis may develop in the rotator cuff, a large group of tendons containing and controlling movements of the shoulder. Rotator cuff tendonitis involves inflammation of one of the four rotator cuff tendons (supraspinatus, infraspinatus, teres minor and the subscapularis) of the shoulder. Another common form of tendonitis may develop at the elbow where the common extensor, flexor tendons attach. Patellar (knee cap) and Achilles (heel) tendonitis are two other common forms of tendonitis.

The onset of tendonitis can usually be attributed to sudden increases in use of the area in question. In many cases, this is related to imperfect motion and muscle balance (referred to as biomechanics) as well as a sudden overuse. For example, a tennis player who adopts a incorrect backhanded stroke, may place undue stress on the elbow.

As we grow older, repetitive use and age can lead to a weathering process that may weaken the tendon where it attaches to the bone, rendering it more susceptible to strain and an inflammatory response by the body. This inflammation can cause “pain on motion,” swelling, warmth, tenderness, and redness. This latter symptom is called “erythema” and refers to the dilation of the blood’s capillaries as part of the inflammatory process. Tendonitis can also occur in areas where calcium deposits have developed. In the latter stages of tendonitis, the tendon will tear, rendering it even weaker.


Most forms of tendonitis can be diagnosed by a physical exam. Palpation and provocative physical exam maneuvers can usual differentiate various forms of tendonitis. A physical Xray cannot directly visualize tendon structures because they are “soft” not bony tissues. MRI’s and Ultrasound exams can highlight inflammation and see tendon structures but are usually not necessary to make a diagnosis, and are only used in cases that are reoccurring or unresponsive to treatment.


The very first line of treatment for tendonitis involves the “RICE” protocol, which stands for “Rest, Ice, Compression, and Elevation.” Methods of treating recurring tendonitis differ for the various body locations of the tendonitis. Other treatments may involve immobilization with a splint, sling, or crutches; or various forms of heat treatment, including skin balms, hot packs, ultrasound. Anti-inflammatory medications such as NSAIDs or (non-steroidal anti-inflammatory drugs), can be effective and direct injection of corticosteroids can be extremely effective.

Again, depending upon the location of the tendonitis, there are some cautions with regard to the type of treatment utilized. For example, repeated injections of corticosteroids in Achilles tendonitis has been associated with an increased risk of tendon rupture, so some reservation is exercised in certain injection uses.

A new and promising treatment is called PRP or platelet enriched plasma. A sampling of the patient’s own blood is drawn into a test tube. The blood is spun rapidly to separate the platelet concentrate from the rest of the blood. Platelets are cells that serve many functions and are filled with inflammatory regulators, growth factors, and healing enzymes produced by the body. This power packed concentrate is injected directly into the area of tendon injury and inflammation to induce a rapid healing response. Results in many cases appear to be dramatic with the advantage that no foreign substance is used and without the potential harm that a cortisone agent might present. The treatment has been used in all forms of tendonitis, bursitis and in some cases of osteoarthritis.

Most cases of tendonitis have a high likelihood of reoccurrence. Rehabilitation and strengthening exercise program can help prevent recurrence. Exercises should focus on strengthening supportive structures around the tendon, and improve the quality of important stressful motions.

For severe forms of tendonitis, surgical procedures may be indicated. Surgical procedures can be used to realign tendons, remove spurs which cause pressure on tendons, or remove areas of calcium buildup. Persistent tendon inflammation combined with overuse in some areas, such as the Achilles tendon or shoulder rotator cuff tendons, may lead to a weakening and a subsequent rupture of the tendon. In these cases, surgical repair of tendon tear may require extended rehabilitation and may also necessitate a protracted recovery.



Bursa is a cavity or sac sometimes filled with fluid. Bursae are situated in places in tissues where friction would otherwise occur. Bursae function to help the gliding of muscles or tendons over the bone or ligament (hard or firm) surfaces. They are found throughout the body; the most important are located at the shoulder, elbow, knee, and hip. Inflammation of a bursa is commonly referred to as bursitis.

A group of bursae also exist around the hip and thigh in the area called the trochanter. This prominent bone is on the side of the hip where the strong muscles or gluteal muscles insert. Constant tension on this wide flat tendon will create friction and inflammation in the bursa sac below it and result in the common trochanteric hip bursits.

Most cases of bursitis are diagnosed by physical exam alone. Additional studies such as an MRI scan are usually performed as a means of excluding the presence of other problems, such as a rotator cuff tear in cases of tendonitis.

Most cases of bursitis will resolve with activity modification, relative rest, and a slow return to activities alongside with proper stretching and strengthening exercises. Anti-inflammatory treatment can be helpful with oral NSAIDs and more recently the availability of a topically applied NSAID creams. Injection of the bursa with corticosteroids can also be very effective as a treatment in recalcitrant cases. Only rarely is surgery used to remove a chronically inflamed bursa.



Arthritis refers to a process in a joint. There are many different types of arthritis, but the most common form of arthritis, osteoarthritis is a degenerative disease that progresses with age.

Inflammatory arthritis on the other hand, can occur at any age. Children and adolescents can be afflicted as well as adults at any age. Examples of inflammatory arthritis include rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis. These conditions are referred to as autoimmune diseases because the root cause is due to disorders within the individual’s immune system and are therefore distinctly different than the more common osteoarthritis. Treatment must focus on control of the underlying process of “auto-immune” related inflammation.

Osteoarthritis occurs as result of wear and tear and age. The normal cartilage surface begins to wear down uyntil underlying bone becomes exposed. The joint becomes painful to move and the range of motion may diminish. This type of arthritis usually involves one or more large weight-bearing joints such as a hip or a knee. With this type of arthritis, pain is usually made worse with activity and better with rest. It is common for symptoms to be at their worst at the end of the day.


Potential causes of arthritis include long term repetitive activity exposure, such as certain stressful sports or occupations, or specific traumatic injuries to the joint. Above all it appears that genetic factors inherited at birth make individuals predisposed to certain forms of arthritis. If your parents suffered with different forms of arthritis you may be more likely to experience similar problems.


Routine x-ray’s are sufficient to diagnose and evaluate established osteoarthritis. MRI’s, CT or bone scan tests may, however, detect early stages and more subtle presentations of arthritis. These tests will also detect the presence of joint inflammation or synovitis which may create swelling and fluid expanding the joint cavity.

X-ray exams may be additionally useful in assessing the alignment of a joint. The alignment appears to be one of many determinants in the possible causes of arthritis. Less than optimal alignment may predispose the joint to stresses of wear and tear.


Exercise and activity regulation are important treatment approaches to different forms of Osteoarthritis. Exercises that improve the flexibility and strength of the muscles surrounding and supporting a joint will help protect a joint structure from reoccurring stresses or “microtrauma” events that might otherwise be detrimental to the health of the joint. Properly performed exercise will encourage more controlled motions during actual sports or daily activities.

Often muscles that have been weakened by periods of disuse or deactivation must be strengthened and encouraged through exercise stresses. Muscles may significant atrophy during periods of joint pain and inflammation. Pain related inhibition during normal motions (walking, running, throwing etc.) may leads to abnormal muscle patterns that are adopted and can be reversed with strengthening exercises.

Nonsteroidal anti-inflammatory medications can used to control periods of more severe inflammation. Corticosteroid medications taken orally are rarely used for OA. Corticosteroid injection directly into an affected joint can be effective if used for a specific flair up of joint inflammation. Sometimes this can only be assuredly accomplished with the use of radiographic guidance. In deeper seated joints such as the hip joint, or small joints that are difficult to find, an ultrasound, or fluoroscopic guidance will confirm the delivery of the steroid medication into the joint.

Viscosupplimentation refers to the placement by direct injection of lubricant like substances into an arthritic joint to temporarily improve its function. Several products are now commercially available that can be injected by the physician into the joint. The injection is usually performed in series of 3 injections spaced one week apart. Improvements typically last from 3 to 6 months and occasionally as much as a year.

Glucosamin and condroitin are two substances available over the counter that have been used to control symptoms of knee OA. Clinic studies have suggested they may have some benefit for patients with knee OA who are experiencing more than the average pain.

Joint replacement has become the gold standard for treatment of OA of the hip, knee and shoulder.

Advances in technology have made theses operation fairly routine and limited the risk and morbity.