September 10, 2013
Frozen Shoulder – what, why and how?
Frozen shoulder is a puzzling and often misused diagnosis. There are a variety of injuries that can lead to reduced shoulder movement and it’s worth noting that the term “frozen shoulder” isn’t a catch-all term for such injuries, as sometimes assumed by patients. Frozen shoulder refers to the inflammation of one particular structure in the shoulder – the joint capsule. This capsule covers the head of the humerus (the upper arm bone) and affixes it to the cavity of the shoulder. In cases of frozen shoulder this capsule becomes inflamed, tightened and sticky – hence “frozen shoulder” being referred to clinically as adhesive capsulitis.
The cause of this inflammation remains somewhat of a mystery. It is thought that adhesive capsulitis is often proceeded by injury or degeneration in other areas of the shoulder; becoming, therefore, the final unwelcome culmination of various smaller pathologies. The cycle of inflammation and repair caused by tendinopathies of the rotator cuff or biceps tendon, for example, can lead to irritation of the shoulder capsule and a progressive tightening. This certainly doesn’t mean that all shoulder pain will lead to adhesive capsulitis if left untreated, far from it. It remains a fairly uncommon condition, affecting only 2 to 3 percent of the population and most commonly those over the age of 40. Frozen shoulder is also thought to affect certain people more than others; diabetics, for example, due to the associated damage to small blood vessels that accompanies the disease. Some studies have also suggested that adhesive capsulitis may even be an autoimmune condition, whereby the body attacks its own tissues, therefore more frequently affecting those with pre-existing autoimmune conditions. Such an autoimmune reaction is thought to be triggered by tendon degeneration in the area.
So how does frozen shoulder feel and what sets it apart from other shoulder conditions? Patients often complain, initially, of an inability to reach behind the back, for example, when fastening a garment. Pain tends to present as a general shoulder ache and is usually relieved with rest. Often it can interrupt sleep if the patient lies on the affected shoulder. These early symptoms, however, are also consistent with other shoulder pathologies such as rotator cuff tendinopathies. What sets a frozen shoulder apart on examination is pain and a reduced range of motion when the shoulder is passively moved by the examiner, i.e. the movement is performed by the practitioner, therefore removing the action of the patient’s shoulder muscles, and implicating a true shoulder joint pathology.
The development and progression of a frozen shoulder is described in 3 stages; the painful stage, the adhesive stage and the recovery stage, each said to last roughly 6 months. The painful stage involves a gradual increase in pain and immobility. The adhesive stage is the period during which active and passive movement of the shoulder is almost completely lost and the recovery stage is a painless stage with a gradual return of mobility. Although 18 months may be a dauntingly long amount of time to suffer from debilitating shoulder pain and immobility, it can often be reassuring for patients to at least hear that there is a fairly standard progression and prognosis. Often chronic pain can feel as though it will never recede, so having a timeline for recovery can be surprisingly comforting in itself.
So, can manual therapy help? Yes, but don’t expect miracles. Manual therapy can be a very useful catalyst for recovery assuming that there is a commitment from the practitioner and the patient. The time of recovery can be reduced with regular manipulation and passive articulation of the shoulder joint, as well as the appropriate homework from the patient. By keeping record of even the most seemingly insignificant improvements in range of motion, the practitioner can also help to install a feeling of positivity and optimism in the patient which will help further with recovery.
- Cailliet, R., 1991. Shoulder Pain. 3rd ed. Jaypee Brothers, New Delhi, India
- Chila, A., 2010. Foundations of Osteopathic Medicine. 3rd ed.
- Siegel et al, 1999. Adhesive Capsulitis: A Sticky Issue. American Family Physician.