Making more sense of the 'frozen shoulder'

Frozen shoulder is one of the more peculiar conditions affecting the musculoskeletal system. While it can occur after trauma, surgery, or prolonged immobilization, frozen shoulder often arises without any apparent precipitating event. It most commonly affects middle-aged females, and risk factors include diabetes, thyroid problems, and coronary artery disease. Interestingly, 20-30% of people who have had frozen shoulder will eventually get it on the other side.

The long-term prognosis for frozen shoulder is thought to be good, with people passing through three stages and ultimately resolving within 12-24 months, regardless of treatment. These stages include:

• A freezing stage, where pain dominates and range of motion slowly decreases.

• A frozen stage, where the pain gradually subsides but the stiffness remains.

• A thawing stage, where range of motion gradually returns.

What we are learning, however, is that not everyone with frozen shoulder will move through all three stages and spontaneously recover as anticipated. In fact, research has shown that up to 50% of people are left with a loss of shoulder motion that persists beyond the expected time frame for recovery.

To combat this confusion, the terminology surrounding frozen shoulder is shifting towards two stages, denoted by whether pain or stiffness is the main feature. Characterizing frozen shoulder as "pain predominant" or "stiffness predominant" is helpful from a management perspective, as each stage requires unique interventions that serve a different purpose.

Before frozen shoulder can be treated, however, it must be differentiated from conditions that are more rapidly reversible, as well as those referred from the spine. Even though these presentations can mimic frozen shoulder, their management is much different.

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Once frozen shoulder is ruled in, one must determine whether pain or stiffness is the dominating feature. The pain-predominant stage is first, followed by the stiffness-predominant stage, and although there can be some overlap between these two, the essential qualities of each are relatively distinct.

In the pain-predominant stage, patients will complain of constant symptoms that are aggravated by all shoulder movements. Inflammation is the primary pain generator, and every attempt should be made to not agitate the shoulder with vigorous activities or therapy during this time. The goal of treatment during the pain-predominant stage of frozen shoulder is symptom reduction and inflammation control. Movement is still beneficial in order to retain as much range of motion as possible, since it will decrease as the condition progresses. A good rule of thumb is that any increase in pain with movement should settle down quickly afterward.

An article in the Journal of Orthopaedic and Sports Physical Therapy, "Shoulder pain and mobility deficits: adhesive capsulitis," stated there was Level A (very strong) evidence for injections in the right patients with frozen shoulder. Ideal candidates for this intervention would be those in the pain-predominant stage, where symptoms are constant and easily aggravated.

Once someone is out of the pain-predominant stage (which can take several months) and stiffness becomes the overarching feature, the aim of treatment is to recover the lost range of motion. By this time, the shoulder capsule, which holds the shoulder joint together, has undergone structural changes that render it short and tight.

This loss of motion, which can be drastic, is very consistent during the stiffness-predominant stage. Someone wouldn’t have days where they could move a lot farther than others. In addition, people tend to complain of pain only when the shortened shoulder capsule is stretched to its capacity. When they move away from the limit of their motion, pain should subside.

The ideal way to restore restricted range during this stage is through remodeling of the shortened tissue. Remodeling is best achieved through specific movements performed several times per day, with enough force to provide adequate stimulus for change. Pain should be produced at the end range of these movements but should stop shortly after the stress is released. If pain persists long after stretching is completed, it’s a sign that overloading has taken place. Restoring range of motion is slow and can take months, but compared to natural history, it greatly speeds up the process of recovery.

Some treatment programs attempt to reestablish shoulder range of motion through vigorous stretching several times per week. While motion will likely be gained using this approach, it doesn’t last. If you want to create long-term changes to structurally altered tissue, it must be slowly remodeled over time.

People often go wrong in treating frozen shoulder because they don’t adhere to the stages. They are either too aggressive in the pain-predominant stage or don’t fully understand how to remodel tissue in the stiffness-predominant stage. It is for this reason that some research has shown people who attend therapy for frozen shoulder have the same outcomes as those who don’t.

Successful management of frozen shoulder starts with an accurate diagnosis, and then applying the correct intervention depending on whether pain or stiffness is predominant.

Dr. Jordan Duncan was born and raised in Kitsap County and graduated from the University of Western States in 2011 with a Doctor of Chiropractic Degree. He practices at Silverdale Sport and Spine.

This article originally appeared on Kitsap Sun: Making sense of the 'frozen shoulder' and how to treat the pain