Antalgic effect and clinical tolerability of hyaluronic acid in patients with degenerative diseases of knee cartilage: an outpatient treatment survey.

A total of 40 outpatients (28 men and 12 women) aged between 18 and 82 years with primary or secondary symptomatic knee osteoarthritis (OA) were selected for this retrospective study. The patients were treated weekly with an intra-articular injection of hyaluronic acid of biofermentative origin. A total of five injections were given, with a follow-up visit at week 7. The aims of this study were to analyze the antalgic effect and tolerability of the procedure, evaluated by overall tolerance, Lequesne's Algo-Functional Index (AFI), pain level evolution and analgesic consumption. No systemic adverse effects related with the device were reported. Global tolerability was judged as excellent/good by almost all the patients and the investigator; 16 patients reported a mild burning sensation at the injection site, which was more frequent during the first injection and resolved within a few minutes. The mean value of the AFI decreased from 7.9 at the initial visit to 3.2 at the final visit, parallel to a decrease into the relative scores of the pain scale. We can thus conclude that intra-articular injection of hyaluronic acid of biofermentative origin appears to be a safe and effective therapy for gonarthritic pain.