Caution should be used in long-term treatment with oral compounds of hyaluronic acid in patients with a history of cancer.

Intra-articular administration of hyaluronic acid is a valuable therapeutic tool for the management of patients with osteoarthritis. However, in recent years numerous formulations containing hyaluronic acid administrable by oral route have entered the market. Even if there are some data in the literature that have shown their effectiveness, systemic administration may expose a greater risk in certain situations. In fact, although hyaluronic acid is not considered a drug it is certain that it can interact with specific receptors and promote cell proliferation. This interaction may be potentially hazardous in cancer patients for which these oral formulations should be contraindicated.

Intra-articular injection of hyaluronic acid (MW 1,500-2,000 kDa; HyalOne) in symptomatic osteoarthritis of the hip: a prospective cohort study.

INTRODUCTION: Clinical trials have demonstrated the safety and efficacy of hyaluronic acid-based products for the treatment of hip osteoarthritis, but data from observational studies of normal medical practice are scarce. This study investigated the long-term efficacy and tolerability of ultrasound-guided intra-articular sodium hyaluronate (MW 1,500-2,000 kDa; Hyalone) injections in daily clinical practice. METHODS: In this observational, cohort study of patients with hip osteoarthritis, Hyalone was administered under the ultrasound guidance, every 6 months, with the possibility of an additional injection at the intervening 3-month intervals on clinical request. Efficacy measurements included the Lequesne algofunctional index, self-reported pain via the visual analogue scale (VAS), the concomitant use of non-steroidal anti-inflammatory drugs (NSAIDs) and safety. The patients were followed up for 18 months after the first intra-articular injection. RESULTS: Data from 120 patients were collected. During the study, a statistically significant reduction in algofunctional indexes was demonstrated at 3 months after study product injection, while at 12 months 80% of the patients achieved a decrease of at least 30% in symptoms. These results were maintained over time through cyclical and personalized repetition of ultrasound guided injections, at least one injection every 6 months. CONCLUSIONS: The study treatment reduced pain and improved mobility in osteoarthritis of the hip. These results in daily clinical practice demonstrate a beneficial effect and the safety of the study product and suggest adding intra-articular injections of HyalOne to the armamentarium of conservative management of symptomatic hip osteoarthritis.