Definition
Metatarsus varus
- adduction of the forefoot at the TMTJ
Intrauterine positional deformity / packaging defect
Epidemiology
1:1000
- M = F
- bilateral in 50%
- 10% have CDH
Aetiology
Unclear
Theories
- intrauterine positioning defect
- prone nursing
NHx
85% resolve by age 3 years
Weinstein
- 31 patients 45 feet with 33 year followup
- 16 feet mild or mod deformity passively correctable, no treatment
- 29 feet partially flexible or rigid treated manipulation or casting
- good results in all the untreated feet
- 90% good results of the casted feet
No poor results
DDx
CTEV
ITT / PFA
Hyperactive Abductor Hallucis
Skewfoot
Clinical Features
Curved lateral border
- forefoot adducted & slightly supinated
- deformity usually fully correctable
- prominent base of 1st metatarsal
Heel Bisector line
- line through midline axis hindfoot
- should pass through second web space
Intoed gait
- exclude ITT
- exclude PFA
DDx CTEV
Metatarsus adductus
- full range of ankle dorsiflexion & mobile hindfoot
Classification
Grade 1 - actively correctable deformity
Grade 2 - passively correctable
Grade 3 - unable to passively correct
X-ray
Not routinely required
Management
Non-operative
Algorithm
< 6/12
- observation only
- sleep supine
> Age 6/12
- rigid deformity
- serial casting changed every 2 to 3 weeks
- 8-12 weeks treatment
- most will tend to partially recur over time
Operative Management
Indications
Controversial
Surgery if difficulty wearing shoes / severe / > age 3
Options
1. Abductor hallucis release
2. MT osteotomy
3. Supramalleolar derotation osteotomy
4. Opening wedge osteotomy medial cuneiform, closing wedge osteotomy cuboid, osteotomies of 2-4