The Coldest of Shoulders
Understanding and Not Understanding Adhesive Capsulitis
Marilyn first noticed the right shoulder pain when she was sleeping on her right side. Over the next month, the pain became more frequent and more intense. Her shoulder ached in the morning and after any repetitive activity. Marilyn tried medications and ice, but the pain persisted. After eight weeks, the pain decreased, but her shoulder movement had become restricted. Her shoulder became so tight that she developed difficulty with activities of daily living such as fixing her hair, dressing, and bathing. Marilyn had developed a “frozen shoulder” and the frustrating thing was that she had no idea why it had happened.
No one fully understands why a frozen shoulder develops. For some reason, the envelope of tissue that surrounds the glenohumeral joint–the joint capsule, shortens and develops thickened adhesions or scar tissue. The medical term is “Adhesive Capsulitis”. This tissue restriction limits the ability of the humeral head (upper arm bone) to rotate and glide properly so your shoulder becomes tight and painful.
Most of the time, a frozen shoulder occurs with no associated injury or activity. Frozen shoulder most commonly affects patients between the ages of 40 and 60 years old. It is far more common in women than men. Individuals with diabetes are at far greater risk. If you have undergone a surgery or sustained a trauma to the shoulder, you can develop a frozen shoulder. This is especially true if you have held the joint immobile for a period of time. Several studies have linked Parkinson’s disease, thyroid problems, and heart disease to a greater incidence of frozen shoulder. Patients that develop a frozen shoulder are more prone to getting it in the opposite shoulder. Despite all of this knowledge, we continue to see many frozen shoulder patients that have none of these predisposing factors.
I would add another condition to the commonly mentioned predisposing risk factors for frozen shoulder. In my career as a physical therapist, it has been a rarity to find a frozen shoulder patient who was strong. From grip strength in the hand to the muscles that hold the shoulder blade on the rib cage, these patients are usually weaker than their same age and sex peers. The strength in the unaffected arm is often as limited as the arm with the frozen shoulder. My belief is that the most common risk factor for developing a frozen shoulder is upper body weakness. The glenohumeral joint is a fairly unstable joint that relies on the integrity of the muscles to kept it free from trauma. If the shoulder muscles are unable to properly control the joint, then excessive stress is transmitted to the joint capsule and an inflammatory response ensues that scars and tightens the capsule.
Physical therapy for a frozen shoulder consists of manual therapy to stretch out the shortened joint capsule and a program of exercise to restores shoulder range of motion, coordination, and strength. Most of the time, we get the patient when the shoulder is at its tightest point and recovery takes six to ten weeks. As with so many conditions, the patients that get to therapy earlier or before the shoulder is fully frozen do better with therapy.
In many ways, Marilyn is the typical frozen shoulder patient. She is the correct, age, sex, and fitness level. Further medical work up revealed that she was prediabetic and in need of some ongoing medical attention. Marilyn was a model physical therapy patient and her shoulder function was restored with six weeks of physical therapy.
Michael S. O’Hara, PT, OCS, CSCS