Investigations for frozen shoulder
Frozen shoulder is mostly diagnosed clinically, ie from what the patient tells us and what the doctor finds in the examination.
However, investigations are performed to exclude other diagnoses and to identify more closely the exact nature of the problem.
The full blood count (all the cells in the blood in the right proportions and numbers), the erthrocyte sedimentation rate (how far our red blood cells sink in a hour in a test tube), and the HLAB27 test (for likelihood of having an arthritic disease) are all normal.
X-rays of the shoulder are normal in appearance, with perhaps some loss of bone density due to not using the area.
This investigation involves the injection of dye into the joint, a special dye which shows up on an xray. The dye fills the joint and so shows up a normal or a tight and contracted joint space. In frozen shoulder the space of the joint is much reduced and this shows on the xray film.
This has not shown up any significant or diagnostic changes which would be of help.
Arthroscopic examination (keyhole surgery) of the shoulder joint allows the surgeon to see directly what has happened to the tissues inside the joint. The major abnormal finding is a scarring up of one of the areas in the front of the shoulder joint.
A fold of the shoulder capsule in the armpit area is also contracted up but there are no adhesions as such in the joint. A tightening up of a major joint structure, the coracohumeral ligament, may be the main lesion in people with frozen shoulder.