Performed by – Ankit Desai, Gareth Hill, Philip Rosell

Frozen shoulder or adhesive capsulitis is a very painful condition of the shoulder. It is common in the 35-55 year old age group and is not usually related to injury. The striking features of the condition are the combination of severe pain, especially at night or rest, along with marked stiffness of the shoulder with loss of rotational movement such as placing a hand behind your back. The condition goes through three stages, known as the freezing, frozen and thawing phases. Each phase typically lasts between 6 and 9 months but sometimes this timeframe is extended.

Cause
The cause of this condition has not been fully explained but there are changes which have been identified in the joint capsule which cause it to thicken and contract. The capsule is the lining of the joint which is normally quite loose and elastic to allow movement in all directions. When it becomes inflamed it will thicken up and became irritable causing pain. The thickened joint capsule retracts into itself and effectively shrinks the size of the joint lining which in turn limits the movement.

During the freezing stage, there is an increasing degree of pain, often described as a burning sensation over the outside of the shoulder joint. This is accompanied by a steady reduction in the range of movement until the arm can only really be moved by rotating the shoulder blade against the rest of the body.

The frozen stage follows and is most notable for the severe limitation of movement. However during this period, the pain has usually reduced or gone completely so that it is often not a major feature.

The thawing phase will then take place with a slow return of movement over several months. The first movement to return is lifting the arm forward (elevation) then sideways movement (abduction) and lastly rotation.

The condition is commoner in people who have diabetes, and they can suffer from the condition in both shoulders at the same time in the most severe cases. Diabetics also tend to take longer to recover.

Treatment
The main effort in treatment is initially to reduce or stop the pain and then to restore movement. In the early stages the changes can be reduced or even reversed by an injection of steroid and local anaesthetic into the joint. Due to the thickening of the joint capsule and the inflamed nature of the joint it is usually uncomfortable to have an injection, but it can speed the recovery in acute cases.

Early diagnosis allows for earlier injections which can help pain and try to prevent significant stiffness from occurring.

If after a period of time things have not improved with injections and physiotherapy, surgery may be offered.

Surgery may be offered either to treat pain or restriction of movement and is usually a keyhole procedure where the joint is inspected using a telescope and the inflamed lining is released from the inside out using a cutting probe placed through a second keyhole at the front of the joint. The most critical area of thickening has been shown to be the rotator interval, a gap between 2 of the muscles of the rotator cuff, and releasing this has good results with movement and function being restored in most cases.

After surgery for a 2-4 weeks there may be more pain present as we encourage aggressive early mobilisation to restore function. If the shoulder is rested too much after surgery for frozen shoulder, then there may be a return of stiffness.

Occasionally, movement can also improved by a manipulation under anaesthetic only without surgical intervention, where the arm is forced through a range of movement and usually the capsule is felt to stretch and give way allowing the recovery of function. This can be a painful procedure post manipulation and it is important to take painkillers to help maintain movement afterwards. There is a very small risk of breaking the arm when this procedure is performed.