What is a Hyaluronic acid injection?

What is hyaluronic acid?

Hyaluronic acid is a naturally occurring substance found within many connective tissue types including joints. It is produced by the articular cartilage and the synovial membrane of the joint and is responsible for shock absorption and lubrication, allowing the joint to move freely (Sirin et al., 2018). Research has shown that to be an effective joint lubricant hyaluronic acid needs to be thick and viscous (sticky). However, in the presence of osteoarthritis of the knee, naturally occurring hyaluronic acid can become thinner and lose its viscosity.

Naturally occurring hyaluronic acid can be supplemented in patients with osteoarthritis via injection. Research has shown that injecting a synthetically produced version of hyaluronic acid into a knee joint can reduce pain and increase functional ability and quality of life, as well as postpone total knee replacement (Altman et al., 2015; Baron et al., 2018; Maheu et al., 2019; Gigis et al., 2016; Bahrami et al., 2020; Wu et al., 2021; Vannabouthong at el., 2018; Hwang et al., 2020; Trellu et al., 2015; Koh et al., 2019).

Hyaluronic acid supplementation has been shown to work in a multitude of ways (Altman et al., 2015). These are as follows:

Healthy articular cartilage is promoted by inhibiting the death of chondrocytes (articular cartilage cells) and promoting the development of new chondrocytes.
Key proteins found in the articular cartilage are stimulated.
Hyaluronic acid produces anti-inflammatory mediators which helped to reduce pain and inflammation associated with synovitis.
The viscosity of hyaluronic acid (known as viscoelasticity) increases joint lubrication and shock absorption.
Subchondral bone (the layer of bone found underneath the articular cartilage which becomes exposed during the process of osteoarthritis) density is increased.

This video should not serve as a replacement for professional health or medical advice.
Always consult a health professional before starting a new exercise or fitness programme.
Please stop and consult a physiotherapist if these exercises cause you pain.