The AC joint is subjected to substantial loading during all shoulder movements. It is also the key component in the shoulder's "suspension system" from the body. This joint is very small, surrounded by powerful ligamentous structures and possesses a meniscus-like disk in its interior that acts as a shock absorber. An accident may damage this meniscus and cause premature wearing. The treatment of painful arthrosis in this joint involves conservatively removing the joint surfaces and the meniscus, while preserving the capsular ligament apparatus so as not to jeopardise stability.