The hyaluronic acid gel that is made by cross linking to ensure the longevity and durability also enables this product to be used for medical purposes outside of cosmetic medicine. Examples of such are for back pain where the gel is re injected into the disc of a old vertebral disc to help increase the disc space between the bones of the back so they don’t rub and irritate the surrounding nerves that cause the pain. Filler injections are also used for areas where knee cartilage has worn away through over use or injury. Rare uses are for clitoral stimulation or vaginal rejuvenation or in some cases to help with bladder incontinence by raising the neck of the bladder upwards. Trials have also been ongoing for anal fistulas but have not had a great deal of success so far.