H

Hyaluronic acid

Hyaluronic acid is a lubricating substance commonly used for knee injections in patients with knee arthritis.

Hydrogel

Hydrogels are three-dimensional (3D) cross-linked networks that swell in water and can be used as scaffold for seeding cells and growth factors into tissues such as cartilage defects.

Hyperextension

Hyperextension is when the knee can bend a bit backwards. Page updated November 2023 by Dr Sheila Strover (Clinical Editor)

Hyperextension injury

A hyperextension injury is one caused by excessive hyperextension (knee bending backwards). Page updated July 2024 by Dr Sheila Strover (Clinical Editor)

Hypermobility

Hypermobility means that the joints are unusually mobile. Page updated July 2023 by Dr Sheila Strover (Clinical Editor)

Hypermobility syndrome

A hypermobility syndrome is a group of symptoms and signs tending to occur together and in which the joints are unusually mobile.

Hypertrophic

Hypertrophic is a descriptive term for abnormal overgrowth of an organ or a tissue.

Hypertrophy

Hypertrophy means excessive growth.