Hallux Valgus (Bunions)

Hallux valgus refers to a subluxation of the 1st metatarsophalangeal (MTP) joint with lateral or valgus deviation of the great toe and medial or varus deviation of the 1st metatarsal, leading to a bony prominence at the medial aspect of the joint (medial eminence or bunion).

Synonym(s): Bunion; Metatarsus primus varus

More common in females; Female: Male = 10:1

Familial tendency

Almost exclusively seen in shoe-wearing societies

Prevalence is highest in women in their 4th through 6th decades of life.

Constrictive footwear and high-heeled shoes

Pes planus and forefoot pronation lead to increased pressure on the medial aspect of the great toe and attenuation of the medial capsular structures at the 1st MTP joint.

A rounded MTP articulation is more prone to lateral subluxation then a flat articulation.

Metatarsus primus varus and an increased 1st and 2nd intermetatarsal angle are often implicated in juvenile or adolescent hallux valgus.

Tight Achilles tendon

Hypermobility of the 1st metatarsocuneiform joint

Neuromuscular disorders and collagen-deficient disorders

Avoid tight-fitting shoes and shoes with an excessively high heel (ie, >1 inch).

Correct for overpronation with orthotics.

Pes planus and forefoot pronation lead to increased pressure on the medial aspect of the great toe and attenuation of the medial capsular structures at the 1st MTP joint.

The abductor hallucis is located medially and provides support to the alignment of the great toe.

A hallux valgus deformity develops, the abductor hallucis tendon is displaced in a plantar direction, and the joint loses most of its medial support.

The adductor hallucis then pulls the proximal 1st phalanx laterally and exerts a rotational force, resulting in pronation of the 1st phalanx.

With worsening of the hallux valgus deformity, the extensor hallucis longus shifts into the 1st metatarsal interspace and becomes a lateral force on the great toe.

With continued lateral pull of the 1st phalanx, the 1st metatarsal deviates medially in relation to the sesamoids and leads to the appearance of subluxation of the sesamoids.

Hammer toe deformity of the 2nd toe

Pes planus

Ingrown toenails in the great toe or the 2nd toe

Metatarsalgia

Plantar keratosis beneath the 2nd metatarsal head

Pain over the medial eminence aggravated by tight or rigid footwear is the most common complaint.

Pain under the 2nd metatarsal head with a plantar keratosis is also common.

Blisters, swelling, callus formation, or bursitis over the medial eminence may occur with athletic activities.

Patients may describe forefoot widening or difficulty wearing shoes comfortably.

Numbness or tingling of the medial aspect of the great toe may occur from pressure on the medial dorsal cutaneous nerve to the hallux.

Note the severity of hallux valgus and rotational deformity of the great toe in both the standing and nonweight-bearing positions.

Assess for pes planus and excessive pronation.

Check active and passive range of motion at the 1st MTP joint (normal extension is ∼70 degrees).

Evaluate sensation of the great toe.

Evaluate for tightness of the Achilles tendon.

Hallux rigidus (degenerative arthritis of the great toe MTP joint with dorsal bunion)

Hallux interphalangeus (valgus at the interphalangeal joint, not the MTP joint)

Gout

Osteoarthritis of the 1st MTP joint