Because they run
The infiltrations of hyaluronic acid are used in the conservative treatment of arthrosis. This technique, tested for the first time in the early 1970s, involves intra-articular injection of sodium hyaluronate.
Intra-articular injection of hyaluronic acid is also known as viscosupplementation, referring to the visco-elastic properties of this substance.
Benefits and Effectiveness
Hyaluronic acid is a polysaccharide, formed by the repetition of a disaccharide consisting of N-acetylglucosamine and glycuronic acid, with high molecular weight (4-6 million daltons) and high viscosity.
Produced by type B synoviocytes (synovium cells), hyaluronic acid is an important component of the synovial fluid, where it contributes to lubricating the joint and cushioning mechanical stress (lubricating and cushioning function). Furthermore, it protects the cartilage from the penetration of inflammatory cells and from the lytic enzymes that degrade it.
In patients with arthrosis it is possible to observe - among other things - a decrease in the viscoelastic properties of synovial fluid, associated with a reduction in the synthesis and molecular weight of intra-articular hyaluronic acid. From here, the rational use of the infiltrations of hyaluronic acid directly in the arthrosic joint, to which benefits are attributed as:
- pain relief, improvement of joint mobility and prevention of cartilage degradation with improvement in daily life activities
- anti-inflammatory effect, with reduction of intra-articular effusion
- reconstruction of the superficial amorphous layer of cartilage
- increased density of chondrocytes (cartilage cells)
- clinical efficacy for at least 6 months - 1 year after the infiltration cycle
Not all studies, however, agree on the efficacy of hyaluronic acid infiltration in the conservative treatment of osteoarthritis. Some meta-analyzes have even shown efficacy only slightly higher than with placebo. Other studies have established that the infiltration of hyaluronic acid produces a pain reduction comparable to that of intra-articular injections of cortisone. For this reason, some doctors warn against excessive emphasis on this treatment: currently there is no cure certainly and always effective in the treatment of osteoarthritis. Conservative options include the use of anti-inflammatory drugs, analgesics, steroids, chondroprotectors and physiotherapeutic interventions; in this context the infiltrations of hyaluronic acid can be validly used in the treatment of common painful pathologies linked to joint degenerative conditions typical of osteoarthritis.
Posology and Side Effects
For treatment with hyaluronic acid infiltrations there are no standard therapeutic schemes; in general, infiltrations of 20 mg of hyaluronic acid are used every 7 days for five weeks, to be repeated at least twice a year. Immediately after infiltration the patient can undergo therapeutic exercise.
Initially derived from rooster crests and today the result of biotechnological processes, the products based on hyaluronic acid for intra-articular use are distinguished by their different molecular weight.
If carried out in compliance with the rules of asepsis (hair removal, thorough cleansing and disinfection of the skin, replacement of the needle after aspiration of the drug), the infiltration of hyaluronic acid is safe and well tolerated. At the infiltration site pain, swelling, a feeling of warmth and redness may occur. Poly-allergic individuals may experience systemic effects with hypersensitivity and anaphylactoid reactions.
