Arthritis mutilans, is a rare arthropathy originally described as affecting the hands, feet, fingers, and/or toes, but refers in general to severe derangement of any joint. In the hands, it is also known as opera glass hand (la main en lorgnette), or chronic absorptive arthritis, first described in modern medical literature by Marie and Leri in 1913. Sometimes there is foot involvement in which toes shorten and on which painful calluses develop in a condition known as opera glass foot, or pied en lorgnette.
In Arthritis mutilans, a patient's fingers become shortened by arthritis, and the shortening may become severe enough that the hand looks paw-like, with the first deformity occurring at the interphalangeal and metacarpophalangeal joints. The excess skin from the shortening of the phalanx bones becomes folded transversely, as if retracted into one another like opera glasses, hence the description la main en lorgnette. As the condition worsens, luxation, phalangeal and metacarpal bone absorption, and skeletal architecture loss in the fingers occurs.
Although a 2011 research article stated that disagreements between hand surgeons and rheumatologists remain regarding the indications, timing and effectiveness of rheumatoid hand surgery, Arthritis mutilans may be successfully treated by iliac-bone graft and arthrodesis of the interphalangeal joints and the metacarpophalangeal joint in each finger.