Hallux valgus is characterized as a great toe deflected laterally and bony prominence develops secondarily over the medial aspect of the 1st metatarsal head and neck
Etiology of Hallux valgus
- Hypermobility of 1st Ray
- Narrow footwear
- Contracture of TA
- Hereditary
Pathogenesis of Hallux valgus
Dropped longitudinal arch
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Dorsiflexion of 1st cuneiform-metatarsal joint
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The distal end of 1st MT is displaced dorsally and medially
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Tens Adductor Hallucis draws big toe laterally
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Rotation in long axis so nail face medially
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Flexor Hallucis Brevis with sesamoid is carried between 2 MT heads laterally
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Abduction of toe ineffective
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Medially bony enlargement
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Adventitious bursa over enlargement
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Degenerative arthritis at 1st MTP joint
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Joint become rigid ( Hallux rigidus)
Secondary deformities
- Hammer toe deformity where 2nd toe displaced dorsally by large toe
- Callosities
- Flat transverse arch
- Heads of the middle metatarsals are prominent in soleàabnormal pressure; sore, callus
X-ray findings
- Lateral displacement of large toes
- Degenerative arthritis with narrowing
- Spurs of the MT heads
- Lateral displacement of sesamoids
- Medial exostosis
- Abducted and shortened 1st MT
- Widening of base
- Abnormal obliquity of articulation with 1st cuneiform
Different angles | Mild | Moderate | Normal |
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IMA (Intermetatarsal angle) | <13° | >20° | <9° |
HVA (Hallux valgus angle) | <30° | >40° | <15° |
Piggott Classification for Hallux Valgus
Type I: Congruent articular surface but valgus tilted
Type II: Non congruent articular surface
Type III: Non-congruent and subluxed
Treatment Options
Conservative treatment
- Mild deformity
- Contraindication to Surgery
Preventive measures include stretching exercises, and the use of a toe seperator at night.
Removal of pressure from medial bony prominences relieves bursitis pain
Footwear modification: Enlarged toe portion to accommodate the bunion is effective
Infected Bursa: Incision and Drainage is recommended
MTP Osteoarthritis: Heat, corticosteroids, rest, NSAIDs
Surgical Management
Surgery is not usually done for cosmetic reasons
Mild deformity with congruent MTP joint in Hallux Valgus
Silver Procedure
Medial eminence resection (simple exostectomy) is often done and flush with the medial border of the foot
McBride Procedure
Silver procedure along with releasing adductor tendon from proximal phalanx and transferring it to the neck of 1st MT
Mild deformity with an incongruent MTP Joint in Hallux Valgus
Chevron Osteotomy
V-shaped osteotomy of distal MT is done in the coronal plane then the head is shifted laterally (up to 50% of bone width)
Later they are fixed with K-wires
Mitchells Procedure
Medial eminence is removed
Done step-cut osteotomy is done as shown in figure
Osteotomy is done proximal to the site of chevron osteotomy
Moderate deformity in Hallux Valgus
Needs more proximal metatarsal osteotomies to address deformities at the actual apex
However, they are combined with other bony or soft tissue procedure
Akin Procedure
When deformities are at the interphalangeal joint also
The silver procedure is done to closed medial wedge osteotomy of proximal phalanx
Scarf Osteotomy
Oblique diaphyseal osteotomy with distal and proximal cut
Allows displacement of MT shaft
Fixed with special (barouks) screws
Severe deformity in Hallux Valgus
Lapidus Procedure
Lapidus procedures are indicated in the following conditions:
- Failed other surgical management
- Neuromuscular and inflammatory arthropathy
- Advanced OA of 1st MTP joint
- Kellers Procedure: Removal of at least ½ of the proximal portion of proximal phalanx
- Stone Operation/Mayos Procedure: Partial resection of the metatarsal head
- Both of above
Disadvantages of bone resection include shortening of 1st ray with relative elongation of muscles and tendons acting on the distal phalanx of the great toe which leads to substantial weakness
- Arthroplasty of 1st MTP joint
- Arthrodesis of MTP joint
Arthrodesis of MTP joint recommended angles are:
In Men:15°-20° of extension
In female:35°-40° of extension
Dorsal Bunion
A dorsal bunion is characterized as dorsiflexion of the 1st metatarsal and plantar flexion of the great toe.
Pathophysiologically dorsal bunion is divided into three types:
1. Weak peroneus longus and strong tibialis anterior
Normally peroneus longus acts as plantar flexors for the 1st Metatarsal and inner Cuneiform which counteracts the tibialis anterior that elevates the inner cuneiform and 1st Metatarsal
2. Paralysis of all muscles controlling foot except tricep surae and long toe flexors (strong)
3. Hallux rigidus and flat foot with rocker bottom deformity
Management of Dorsal bunion
Flexible Type
Conservative treatment will correct muscle imbalance between ankle motors
Rigid type
Lapidus Procedure
Steps of Lapidus procedure
Imbrication(double breasting ) of the dorsal capsule of 1st MTP joint
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Capsular release on planter aspects
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Transfer of FHL to the base of 1st Metatarsal
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Wedge osteotomy of cuneiform-metatarsal with/out navicular-cuneiform joints to correct dorsiflexion of 1st Metatarsal