Juvenile Hallux Valgus

Epidemiology

 

More common in girls

High incidence of positive family history (75%)

 

Can be associated with mild CP

 

Pathology

 

Juvenile Hallux Valgus

 

Congruent joint

- 50% compared with 9% in adult HV

 

Metatarsus primus varus

- increased IM angle

- often the primary deformity

 

Epiphyses usually still open

 

Oblique first TMTJ Angle

 

Ligamentous Laxity

 

Difference from Adult HV

 

Less severe

- no arthrosis

- sesamoid subluxation & pronation less common than in adult

- medial eminence not as prominent

- HVA not as big a contributor

 

Examination

 

Ligamentous laxity

 

T Achilles tightness

 

TMTJ hypermobility

 

Neurological examination

 

X-ray

 

Normal Angles

- HV < 15o

- IMA < 9o

- DMAA < 10o

 

Often DMAA increased

 

Management

 

Non-operative

 

Delay any surgery until

- adolescence

- physis closed (but not CI if open)

 

Well fitting shoes

 

Flexible flat foot may benefit from medial arch support

 

Operative 

 

Aims

- reduce DMAA

- reduce IMA

 

Congruent joint 

- less likely to progress (therefore treat conservatively)

- requires extra-articular realignment

 

Options

 

1.  Double or triple osteotomies

 

A.  Akin / proximal phalangeal osteotomy

- corrects interphalangeal angle

 

B.  Chevron biplanar distal metatarsal osteotomy

- adjust DMAA by adding closing wedge osteotomy

 

C.  Proximal metatarsal osteotomy

- further corrects IMA

 

2.  Hypermobile TMTJ common

- Lapidus procedure

 

Hallux Valgus Lapidus Procedure

 

3.  1st Cuneiform Opening Wedge Osteotomy

- severe IM angle with open 1st metatarsal epiphysis

- marked M-C joint obliquity with high IM angle

- opening wedge (iliac crest graft)

 

Complications

 

20% recurrence rate

- failure to correct IMA

 

Hallux varus 

- split extensor hallucis longus transfer

 

AVN 

- rare even in combined distal procedure