What is a Frozen Shoulder?
Adhesive Capsulitis is the medical term for Frozen Shoulder. This is a condition which affects the ability to move the shoulder, and usually only occurs on one side. Sometimes (approximately 1 in 5) the problem can also occur in the other shoulder. The medical term literally describes what is seen in this condition adhesive meaning sticky, and capsulitis meaning inflammation of the joint capsule. It is thought that a lot of the symptoms are due to the capsule becoming inflamed and sticking, making the joint stiff and difficult to move. This is not the same as arthritis, and no other joints are usually affected.
Frozen Shoulder is extremely uncommon amongst young people, and is almost always found in the 40+ age group, usually in the 40-70 age range. Approximately 3% of the population will be affected by this, with slightly higher incidence amongst women, and is five times more common in diabetic.
It is not known exactly what causes this problem, however it is thought that the lining of the joint (the capsule) becomes inflamed, which causes scar tissue to form. This leaves less room for the humerus (arm bone) to move, hence restricting the movement of the joint. The increased prevalence amongst diabetics (particularly insulin-dependent diabetics) may be due to glucose molecules sticking to the collagen fibres in the joint capsule, which causes stiffness. For this reason, diabetics are more likely to have both shoulders affected. Hormonal changes may be responsible for the higher incidence amongst women, particularly due to the increased prevalence around the menopausal period.
The symptoms start with a gradual onset of aching shoulder pain which is often worst at night and when lying on the affected side. As the condition progresses, mobility at the shoulder decreases, making daily tasks more difficult. Pain then tends to ease first, followed by a gradual increase in the range of motion.
Overall, frozen shoulder may last for any length of time, usually between 6 and 18 months.
There is very little treatment which has been shown to really be effective at either relieveing pain or increasing movement when a shoulder is frozen. Physical therapy and treatments such as massage and mobilisations may help to some extent, as may acupuncture and electrotherapy. But unfortunately, at the moment the general course of action is to let it run its course, managing the symptoms as well as possible.
Warming or cooling the shoulder joint may help ease pain. Hot and cold packs are available and can be used both ways, by either freezing or warming in boiling water. A neoprene shoulder support may also help to keep the shoulder warm and encourage blood flow which often helps with pain relief.