Use of local steroid injections.

are rapidly dispersed. The microcrystals may themselves induce an acute inflanmmatory response (a,s in gout) either in the joint or soft tissues. Occasionally this may be intense and prolonged for several days. Numerous preparations are available, but in practice it is useful to have available two or three preparations varing in strength and length of action. The long-acting agents tend to cause more intense and prolonged exacerbations, and are considerably more expensive. Suggested preparations are hydrocortisone acetate, strength 25 mg/cc for which the manufacturers claim a e.aration of about 10 days; methylprednisolone acetate, 40 mg/cc, 21 days; and triamcinolone hexacetonide, 20 mg/cc, 90 days. Slow absorption occurs that may produce a systemic effect on other inflamed tissues, and if injections are given indiscriminately the effect can accumulate and produce hypercorticism. For intra-articular injection there is little benefit in admixing local anaesthetic as it is desirable to keep the injected volume as low as possible, particularly in small joints. Soft-tissue lesions, however, may be difficult to locate with certainty. If a small quantity of dilute local anaesthetic is added to the injection and it produces rapid relief of pain this helps to indicate that the injection was correctly sited.