Our bodies are complex biomechanical machines. A structural frame is provided by our skeletons. The various bones are held together at the joints by muscles, tendons and ligaments and controlled by nerves.
Complex movements, like running, jumping, walking and even eating or dressing involve the orchestrated and precise activation of multiple joints to make this frame move, the right way at the right time, which allows us to function. Even small irregularities of joint movement, such as alignment, pattern or timing can lead to increase risk of injury, poor function or pain.
Our bodies adapt to injuries, pathologies or even lifestyle related postures, learning to alter the symphony of muscle activation, joint alignment and movement. Over time this can result in the body's movement becoming imbalanced or placing excessive load on other joints by compensating for an injury or weakness. Understanding this symphony is called functional analysis and requires accurate measurement of the joints and forces on them during movement.
Traditional imaging technologies like MRI or ultrasound can provide information about what the joint/muscles/tendons look like, but do not tell us how well the joint is working (functional performance).