First Ray Pathology

This refers to conditions affecting the big toe (hallux) and the first metatarsophalangeal joint.

Hallux Valgus (Bunion)

This is the best-known condition causing deviation of the first metatarsal and the big toe. A bump appears on the front inner side of the foot (exostosis/bony prominence). This condition is more common in women and can cause many problems.

First, it causes an inflammatory arthritic reaction that can be very painful. There is a loss of motion in the first metatarsophalangeal joint, which can impair walking. The bony prominence rubs against shoes, causing irritation.

Additionally, the first metatarsal undergoes inward rotation, making the support system (the first metatarsal head and sesamoid bones) unstable and painful.

This support system is essential during the push-off phase of walking. When it fails, the neighboring metatarsal heads are often overloaded, leading to metatarsalgia (pain in the ball of the foot).

The cause of this condition is mainly genetic or related to environmental factors such as poor footwear or excessive pressure on the first ray (inner side of the foot).

Treatment

Orthotic insoles can relieve pressure pain and slow the progression of the deformity by offloading the area.
In early stages, a toe spacer placed between the first and second metatarsals may also slow progression.
To correct the deformity and remove the bony prominence, surgery is required.
A podiatrist will also provide footwear advice.

Functional Insufficiency of the First Ray

This refers to excessive mobility of the inner column of the foot (all the joints running from the big toe to the hindfoot).

This hypermobility causes poor support from the first metatarsal, shifting pressure onto the neighboring metatarsals and leading to metatarsalgia. It can also spread to the midfoot and result in a flat valgus foot.

Treatment

Custom orthotic insoles aim to stabilize and restore support to the inner column of the foot.

Hallux Rigidus

This condition is very similar to hallux valgus, but the major difference is that it does not cause toe deviation.

There is an arthritic reaction on the top (dorsal side) of the joint, which may also create a bony prominence called a “dorsal bunion.”

There is a significant loss of joint mobility, and the support system may stop functioning properly, transferring pressure to the big toe. This is referred to as a “cock-up toe” or “bucket toe” deformity.

Treatment

Podiatric treatment aims to offload the first metatarsal head as much as possible to reduce stress on the joint while walking.

Sesamoiditis

The sesamoids are two small bones located beneath the first metatarsal head within the tendons. They play a very important role during the push-off phase of walking.

Different conditions can affect the sesamoids, including:

Fracture
Necrosis
Tendinitis of the muscles attached to these bones

Treatment

The affected area should be offloaded with orthotic insoles to relieve pain and improve comfort.