Defined

A bunion (from the Latin "bunion" meaning largement) is a protuberance of bone or tissue around the joint.  The enlargement occurs either at the base of the great toe or on the outside of the foot, at the base of the little toe and is called a "bunionette" or "tailor's bunion".

Bunions are a valgus deviation of the hallux commonly associated with an exostosis on the 1st metatarso-phalangeal joint.

Symptoms

Pain from a bunion can be mild, moderate or severe, making it difficult to walk in normal shoes, especially those with high heels.  The skin and deeper tissues around the bunion may also be swollen or inflamed, very painful or in other cases exhibit no pain at all.  The other toes can be affected by a bunion, as a result of pressure from the great toe pushing inward toward the lesser toes.  Toenails may begin to grow into the sides of the nail bed; the smaller toes can develop corns and become bent (see hammer toes [coming soon!]).

Biomechanical Aetiology

Excess pronation of the subtalar joint together with a short 1st metatarsal is the most common biomechanical factor.  As the foot pronates, the centre of gravity moves towards the midline, loading the forces on the medial forefoot area.  This action puts excessive weight on the great toe during the toe off phase of gait, increasing the load on the 1st metatarsal shaft in an adductory direction, rotation of the shaft takes place, which then requires the hallux (big toe) to compensate by abducting.  The great toe deviates towards the smaller toes and the joint must get bigger to accommodate the added weight.

Some bunions are caused by arthritis or trauma.  Footwear is not the common cause as generally promoted... this is an urban myth!!  A foot exhibiting a short 1st metatarsal or one that is hypermobile is more susceptible to developing a bunion.  Bunions can run in a family but are not hereditary as it is the biomechanical structure that is hereditary and passed through the family.  Fractures or breaks into the joint may lead to arthritic changes and the development of bunion deformities with limited range of motion.

Treatment

ICB Orthotics control excess pronation (although not forefoot adductus) reducing the load on the medial forefoot area and reducing valgus deviation of the hallux.  ICB Orthotics re-establish proper weight distribution and lower limb biomechanics which may prevent or reduce gradual growth of a bunion.  ICB 2/3 Orthotics can be used in men's shoes or ladies wide fitting flat shoes.

Sometimes surgery may be indicated when the bunion is at a tertiary stage, however ICB Orthotics should be worn after surgery to prevent any reoccurrence.

Exercises

Intrinsic forefoot exercises.

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