A new operative technique in arthroscopic treatment of chondromalacia using ultraviolet laser systems is introduced. The postoperative results are evaluated in a prospective and randomized clinical trial. One hundred and forty patients stage II or III chondromalacia according to Outerbridge were randomly assigned to arthroscopic operation using either laser or mechanical instruments. After a 6-month follow-up period the clinical results were compared, guided by a specially designed modification of the Lysholm scoring scale. In the short-term follow-up laser surgery gave superior results in regard to reducing pain (P < 0.05)="" and="" leading="" to="" a="" lower="" incidence="" of="" reactive="" synovitis="">P < 0.01).="" no="" difference="" was="" found="" in="" respect="" of="" disability="" and="" functional="" impairment.="" our="" results="" lead="" to="" the="" conclusion="" that="" arthroscopic="" laser="" application="" seems="" to="" be="" a="" successful="" procedure="" in="" the="" treatment="" of="" degenerative="" cartilage="" disorders,="" providing="" precise="" ablation="" of="" tissue="" without="" significant="" thermal="" damage="" to="" the="" remaining="">