Inflammation and swelling around the sesamoid bones can be secondary to trauma,
infection, stress fractures, or a systemic disorder.  Sesamoiditis may also be precipitated by a cavus foot with excessive weight bearing under the first metatarsal.  Sesamoid shape may vary and in some cases may be especially thick or pointed.  A sharp pointed sesamoid might cause a deep seated callus to form under it.

Symptoms include pain on weight bearing and with dorsiflexion of the great toe and pain with direct palpation.  The first Metatarsal Phalangeal joint may also show swelling.

Custom orthotics will reestablish proper weight distribution and with an added metatarsal pad,  will also unload the sesamoids from pressure.  By correcting the gait of the foot (usually overpronation) there will be a lesser need for dorsiflexion of the MTP joint again reducing stress of the sesamoids.