Hallux Abducto Valgus (Bunions)
Definition:
A valgus deviation of the hallux commonly associated with an exostosis on the 1st metatarso-phalangeal joint.
Symptoms:
When irritated by tight or ill-fitting shoes bunions can become red and swollen.
Biomechanical etiology:
Bunions are most commonly caused by forefoot adductus and excess pronation of the subtalar joint. Some bunions are caused by arthritis or trauma. Due to excessive pronation, forces load the medial forefoot area. This increased adductory load on the 1st metatarsal shaft causes rotation of the shaft, which then requires the hallux (big toe) to compensate by abducting. Feet that have short 1st metatarsals or hyper mobility are more susceptible to this condition.
Treatment:
Orthotics control excess pronation (although not forefoot adductus) thus reducing load on the medial forefoot area and reducing valgus deviation of the hallux. Sometimes surgery may be indicated. Orthotic treatment post operatively should always be a consideration.
Exercises:
- Intrinsic forefoot exercises
Summary
Hallux Abducto Valgus:
A bony lump on the hallux caused by a combination of genetic factors and poor foot function. Excess pronation combined with forefoot adductus causes growth of the bunion.
Treatment:
Pre-molded orthotic or custom made orthotic.
Other:
Intrinsic forefoot exercises
Corns and Callous
Definition:
Areas of thickened skin on the plantar surfaces of the foot and /or inter-phalangeal joints.
Biomechanical etiology:
Corns and callous develop from excess friction on the foot. Corns normally develop on the upper joints of the toes, whilst callous generally develops on the underside of the foot. Corns and callous commonly develop when excess pronation disrupts the normal metatarsal bone relationship in the foot and this causes the toes to claw. Friction related to footwear is also a major contributor.
Treatment:
Orthotics are designed to control excess pronation and prevent plantar-flexion of the metatarsal bones and clawing of the toes.