Use of Exogenous Hyaluronic Acid for the Treatment of Patellar Chondropathy- A Six-Month Randomized Controlled Trial

 To evaluate the clinical and radiological benefits of intra-articular exogenous hyaluronic acid for the treatment of chondral patellar injury.  Randomized clinical trial with 70 patients divided into 2 groups: those submitted to physical therapy for 3 months, and those submitted to physical therapy associated with the intra-articular administration of 2 mL of hyaluronic acid for the same period, who had anterior knee pain and patellar cartilage injury of grades II or III with no significant bone abnormalities. The functional scores and the characteristics of the physical and imaging exams were evaluated before and 3 and 6 months after the treatment.  The average age of the patients was 32 ± 7.6 years. Patients from the hyaluronic acid group had better Kujala et al and Lysholm scores, and lower pain scores after 3 and 6 months of treatment when compared to the control group. The incidence of positive Clarke maneuver was lower in the treated group, but there was no difference in the magnetic resonance imaging classification.  Patients with patellar chondropathy of grades II or III treated with hyaluronic acid and physical therapy had less pain (visual analogue scale, VAS), and better functional results in the Lysholm and Kujala et al questionnaires after 3 and 6 months of treatment compared to patients undergoing physical therapy alone. In addition, the number of cases with a negative Clarke maneuver was larger in the treated group after 6 months of treatment.