[Assessment of the functional origin of shoulder pain in chronic polyarthritis by diagnostic local anesthesia of inflamed distal joints. A pilot study]. / Nachweis der funktionellen Genese von Schulterschmerzen bei chronischer Polyarthritis durch diagnostische Lokalanästhesie entzündeter distaler Gelenke. Eine Pilotstudie.

We examined 40 patients with rheumatoid arthritis suffering from painful shoulder. While the shoulder itself was not treated, Mepivacain was injected into an arthritic joint of wrist or elbow. In 36 out of 40 patients we achieved full or partial improvement of pain and movement of the shoulder. We conclude that pain in the shoulder of these patients was caused by a regulatory mechanism, triggered by nociceptors in an arthritic distal joint in order to protect this damaged structure. The therapeutic consequence implies treatment of the distal joint rather than treatment of the painful shoulder itself.