This paper describes transcutaneous therapeutic procedures performed during arthroscopy. Sixty-six patients were treated. Small loose bodies were flushed out through the arthroscope in 7 cases. In 19 of 24 knees a loose body 0.5-2 cm in size was extracted either with a Dormia stone-dislodger or a pituitary rongeur. In 5 patients we failed to remove the loose body transcutaneously and arthrotomy was performed. A meniscus was resected in 17 patients using a pituitary rongeur alone or in combination with some other instrument. The late result was good in 14, but 3 subsequently underwent arthrotomy. Various procedures such as lateral release of the patella by a special technique, removal of intra-articular sutures and other measures were also undertaken. No complications occurred and the duration of sick leave was usually short. Before arthrotomy for removal of loose bodies or resection of ruptured menisci is performed, we feel that an attempt at transcutaneous therapy under arthroscopy should be made.