Background Viscosupplementation consists of intra-articular infiltration of hyaluronic acid (HA) to improve viscosity, reduce inflammation and relieve pain in patients with knee osteoarthritis.

Purpose To compare the percentage of patients who required more than one dose of sodium hyaluronate (AdantOne) versus more than one dose of hylan G-F-20 (SynviscOne) in the same knee in less than a year.

Material and methods This was a retrospective observational study including all patients with knee osteoarthritis who were treated with HA between February 2013 and October 2016. This period was divided into two stages: in the first stage (February 2013–January 2015, 24 months), the HA available in the hospital was AdantOne and in the second stage (February 2015–October 2016, 21 months), the HA available was SynviscOne. The variables analysed were: number of patients, dispensed units, date of infiltration and medical service. The data were collected from the hospital pharmacy software programme (Savac) and the medical records programme (Selene).

Results In the first stage, AdantOne was dispensed to 944 patients (789 (83.58%) from traumatology, 138 (14.62%) from rheumatology and 17 (1.80%) from rehabilitation). Of these, 72 patients (7.63%) required ≥2 doses of HA in the same knee in less than a year (63 patients (87.50%) from traumatology, 8 (11.11%) from rheumatology and 1 (1.39%) from rehabilitation). In the second stage, SynviscOne was dispensed to 1193 patients(1039 (87.09%) from traumatology, 137 (11.48%) from rheumatology and 17 (1.43%) from rehabilitation). Of these, 7.63% (91 patients) required ≥2 doses of HA in the same knee in less than a year (78 (85.71%) from traumatology and 13 (14.29%) from rheumatology).

Conclusion The percentage of patients who required more than one dose was the same with the two presentations of HA. However, the second stage was shorter than the first, suggesting that the duration of the effect of SynviscOne is less than the duration of AdantOne. Our results show that the percentage of patients that required two or more doses of HA in the same knee in a time period of less than one year was not very high. These results, along with the price, are important in the selection of HA.

References and/or acknowledgements Viscosupplementation for the treatment of osteoarthritis of the knee. Cochrane Database Syst Rev PMID: 16625635.

No conflict of interest