Editor’s note: This is first in a multi-part series on common ailments. See Eric Dube’s column in March for a look at arthritis.

There is no exception when it comes to inflammation. Everybody will experience some degree of an “itis” at some point in his or her active (or even sedentary) life.

Whether it’s tendonitis, arthritis, fasciitis or one of the many other diagnoses in the inflammatory category, it’s usually quite painful and can be incredibly debilitating. Tendonitis is a very common clinical diagnosis, so it’s worth understanding how these collagen-laden tissues function and respond to stress from our daily lives.

When it comes to the suffix “-itis,” one can assume that there is an inflammatory condition. For example, tendonitis refers to an inflamed tendon, arthritis refers to an inflamed joint and fasciitis refers to inflamed fascia (connective tissue). While inflammation is a normal part of soft tissue healing, it can also be negative when caused by repeated stress and strain.

What are tendons?

Before explaining the underlying causes of inflammation, let’s discuss how your tendons function. Ligaments connect bones to bones, and tendons connect muscles to bones. Both are made of collagen and other connective tissues. Tendon and ligament structures differ slightly in their cellular make-up and format, but they both are designed to have high-tensile strength to transfer energy throughout our body. It’s all connected!

What is tendonitis?

“Tendonitis” occurs when there is a stress/strain on a tendon that results in injury and inflammation. Keep in mind this can be from an acute insult or from cumulative trauma from small events. There are literally countless things that can cause tendonitis, but some common examples include:

Tennis elbow (lateral epicondylitis) is commonly caused by using poor form with too many backswings in the game of tennis.

Patellar tendonitis (front-side knee pain) is typically caused by repetitive jumping and/or deep squatting.

Achilles tendonitis can be caused by wearing a new pair of tall heels during the week, then wearing flat footwear on the weekend.

Whatever the circumstances, the damage stimulates the soft-tissue healing process. Sometimes, this process gets backed up due to repeat trauma (more tennis, more training and squatting, bad posture throughout the day, etc.). As a result, the tissue doesn’t get a chance to recover and can lead to incomplete healing.

Soft-tissue healing is quite complex when you get into the details, but understanding the basics will help you appreciate more about tendonitis.

Phases of healing

Soft-tissue injury has a sequence of phases that eventually leads to optimal restoration of tissue structure and function.

The first phase is the inflammatory phase, when blood vessels dilate to bring in fluid and cells to initiate healing.

The second phase of healing is known as the proliferative phase, when there is an abundance of cells that enter the area to form new collagen fibers. While this process results in new tissue formation, the mass of cells is disorganized and relatively weak. Think of this new tissue layout as haphazard, like strands of overlaid hay.

The third phase of healing is known as the remodeling phase, when appropriate intensity and duration stress results if tissue “reformatting.” This includes fiber strengthening and reorientation into a more linear fashion, like the threads of a seatbelt.

Recovering from a tendonitis

Thankfully, there is a lot that can be done to remedy the woes of the “itis.” Here are some general concepts that hold true when dealing with a tendonitis condition:

When it’s bad, you need to rest and off-load the irritated tendon by not overworking and not overstretching the muscle(s) or affected tendon. (e.g. repetitive squatting or quad stretching is not helpful in the case of an acute patellar tendonitis).

Exercises are essential. Start with isometric (contracting and holding) movements, then progress to isotonics (contraction with muscle movement, as in muscle shortening is concentric and muscle elongation is eccentric). These exercises are specific to the muscles with the affected tendon (e.g. calf strengthening to work on an affected Achilles tendon).

Work to restore balanced strength and stability in the areas above and below the affected body part (e.g. with elbow tendonitis, look at addressing deficits with shoulder strength and posture).

Tendonitis is a very common occurrence, especially if you are active at work or with recreation. It’s a diagnosis that can affect everything from our shoulders to our Achilles in our heels, and it hurts.

Keep in mind: It’s not ideal to diagnose or treat yourself, but it is proactive to be educated about something as important as your very own human body!

Eric Dube is a licensed physical therapist and orthopedic clinical specialist with Howard Head Sports Medicine in Summit County.