The large toe joint in the foot is a crucial joint for normal biomechanics and running or walking. When we are moving and the feet are flat on the ground, that big toe or hallux joint needs to flex while the rearfoot come up off the floor. If that big toe joint is unable to flex then to be able to walk and run will likely be much more challenging. A lot more energy is needed so running or walking becomes very tireing. When the movement which is not able to occur at the great toe or hallux joint still needs to occur, other joints could be made to move a lot more during a period that they are not meant to be moving. This unnatural movement may become painful.
There are a range of things that might go wrong with that big toe joint and reduce that normal motion. One of the more prevalent issues is a disorder that often gets known as hallux rigidus and as this name implies, the joint is inflexible and doesn't flex. The most common cause for this is osteoarthritis of that hallux joint. This could be fairly painful and the inflexible great toe joint tends to make walking very hard. The most widespread handling of this are drugs to decrease your pain, rocker sole footwear to allow for some motion to take place and surgical procedures on the joint.
A less severe type of hallux rigidus can be a condition known as hallux limitus where the hallux joint is not stiff but has a reduced range of flexion. Since a full range of motion is necessary at the great toe joint for normal function, this limited movement is still an issue. The commonest cause for this condition is also osteoarthritis. Typically the management of hallux limitus is relief of pain with drugs, at times taping is used to restrict motion even more so that it is not too painful. Foot orthoses are sometimes used to encourage a more normal movement with the hallux joint. With the most painful cases surgery could be an option in which a joint replacements can be done or the great toe joint is operatively fused to stop it moving.
A different very common condition is called a functional hallux limitus. This is known as functional because in a non-weightbearing evaluation the joint has got a normal range of flexibility, however when functioning with the foot on the ground it just does not have the full range of motion. The reason behind a functional hallux limitus is not really known and the reason why that great toe joint does not work during weightbearing is just not clear. The limitation just seems to happens in some individuals. Several hypotheses have been advanced, many of which seem plausible but there is no direct evidence for one theory above the another theory.
There are a number of treatment options for a functional hallux limitus that are directed at restoring normal function to the great toe joint. Podiatry practitioners frequently use foot orthotics with different design features such as a first metatarsal cut out, the Kinetic Wedge or possibly a Cluffy Wedge. Many of these designs try to increase the flexion at the big toe or hallux joint to make the joint function more efficiently and stop the functional hallux limitus from affecting the walking.