The aim of this work was to assess the efficacy of viscosupplementation after knee arthroscopy in a series of cases and to propose an adequate dosage regimen.The cases studied corresponded to patients undergoing arthroscopic surgery presenting meniscal injury and/or free bodies and where osteoarthritis could be present. Viscosupplementation started 3 weeks after arthroscopy and one set of patients received one shot of 5 ml of hyaluronic acid and the other set received three injections of 2.5 ml with weekly intervals. Patients were followed at 3 and 6 months. Improvements in pain and function as well as patient satisfaction were assessed and the appearance of adverse events was monitored. The groups studied were homogeneous with no differences in the type of surgery, associated gestures or other procedures performed during the intervention. Considering the patients as a whole, significant improvements were observed at 3 weeks post-arthroscopy (prior to intra-articular treatment) and at 3 and 6 months compared to pre-arthroscopy scores. Pain reductions were of 39.8%, 63.4% and 80.9% respectively and function improvement was of 20.9%, 58.8% and 77.9% respectively. There were no differences between the two groups in any of the parameters analysed. The treatment was rated by the patients as excellent. The group concluded that viscosupplementation inpost-arthroscopy achieves significant pain reduction and function improvement; moreover, one shot of hyaluronic acidis a safe and effective option as an adjuvant treatment in arthroscopic surgery favouring a better recovery with a lower cost for both the patient and the Healthcare System.