RenehaVis™

Intra-articular injection of hyaluronic acid (HA) is a type of viscosupplementation, which aims to help restore the knee joints of osteoarthritis (OA) patients to a healthy physiological state. The functions of HA with different molecular weights are explained as follows:
1. Low molecular weight (LMW) HA: (1) acts as a lubricant in the knee joint; (2) diffuses through the cartilage to protect the chondrocytes (note: a molecule which helps create endogenous HA and proteoglycans) which are commonly destroyed in knee OA patients. This is termed as the "CAGING EFFECT"; (3) diffuses to the synoviocytes of the synovial membrane to stimulate production of endogenous HA. This action is known as the "MECHANOSENSITIVE EFFECT."
Briefly, reasons that using a higher concentration of LMW HA includes optimizes the effects of lubrication, cartilage cell protection, and stimulation production of endogenous HA .
2. High Molecular Weight (HMW) HA: Its primary function, "cushion effect," which absorbs shock during activities such as running or jumping, reducing friction and wear between bones. It also protects both soft and hard tissues, helping to slow down the progression of degenerative knee OA. Additionally, some studies have shown that HMW HA has significant anti-inflammatory effects. Furthermore, HMW HA tends to have a longer retention time in the body.
3. MW and Concentration Ratio: The MW and concentration of HA injected into joints do not necessarily improve with higher values. Depending on the composition structure, expected target effects, and other concerns, different products may have different ratios. For instance, a higher concentration of LMW HA theoretically optimizes lubrication, cartilage cell protection, and endogenous HA stimulation, while using an appropriate concentration of HMW HA can effectively deliver the cushioning effect.

Currently, the hyaluronic acid (HA) intra-articular injections available on the market are typically offered in three different injection routes: 5 injections, 3 injections, and a single injection in total. Generally, one injection per week is administered to a single joint. For the single injection long-lasting products, existing clinical data shows that the effects can last between 6 to 12 months, although the actual duration may vary depending on product and the patient's condition. However, a larger single injection does not necessarily mean a higher concentration of HA. The concentration, combined with the molecular weight of the HA, leads to different functional properties (as the answer shown in Q1). Furthermore, excessive injection volume might cause more noticeable swelling and discomfort in the patient after the injection. Thus, the most suitable treatment plan should be determined by professional healthcare providers based on an evaluation of the patient's condition.

The possible side effects after injection may vary depending on the source of the injected substances and other factors, so it is important to carefully read the product’s Instructions for Use (IFU) for detailed information. For hyaluronic acid derived from non-animal sources, concerns about allergic reactions to animal components can be avoided. Common side effects include pain at the injection site, swelling, redness, and stiffness in the knee joint (local injection site).

Regarding the applicable uses for each product, please carefully read through the product’s Instructions for Use (IFU). However, off-label use should be determined by a doctor based on the patient’s situation. In the case of discomfort after use, the patient should promptly arrange for a more detailed and comprehensive evaluation with their doctor.