Hallux limitus is just what its name says. The ‘Hallux’ is the big toe and ‘limitus’ is a limitation in the range of motion of the hallux.
A structural hallux limitus is when there is structurally a limitation in the range of motion of the joint. This is most likely caused by trauma or osteoarthritis. The range of motion of the joint when the foot is up in the air (ie non-weightbearing) is reduced. During gait (ie weightbearing; functioning) it is also reduced. The extreme of a functional hallux limitus is when there is no range of motion, which is generally known as a hallux rigidus.
A functional hallux limitus is when there is only a limitation in the range of motion when functioning. The cause of a functional hallux limitus is not clear. The range of motion of the joint when the foot is up in the air (ie non-weightbearing) is normal. During gait (ie weightbearing; functioning) it is reduced – hence the name functional hallux limitus as the limitation is only present when functional.
