What is the treatment for metatarsus varus?

Treatment for Metatarsus Varus

Begin conservative treatment immediately upon diagnosis with manipulation exercises, progressing to orthotic devices (Bebax-type braces or UNFO) if manipulation alone fails, reserving serial casting for rigid deformities and surgery only for severe cases unresponsive to all conservative measures.

Initial Assessment and Classification

Classify the deformity severity at presentation using the Bleck classification system 1, 2:

• Flexible: Forefoot can be passively corrected past neutral
• Semi-flexible: Forefoot can be corrected to neutral but not beyond
• Non-flexible/Rigid: Forefoot cannot be passively corrected to neutral

The heel bisector line (HBL) provides objective measurement—severe deformity shows the line at or lateral to the 4th toe, while moderate deformity shows the line between the 3rd and 4th toes 3.

Treatment Algorithm by Severity

Flexible and Semi-Flexible Deformities

First-line: Manipulation exercises 1, 2

• Start immediately at diagnosis
• Perform multiple times daily by parents/caregivers
• Approximately 42% of flexible/semi-flexible cases resolve with manipulation alone 1
• Continue for 4-8 weeks before progressing to orthotic treatment

Second-line: Orthotic devices if manipulation fails 3, 1, 2

• Bebax-type braces are effective for cases not responding to manipulation alone, with approximately 57% of initially manipulation-treated patients requiring this escalation 1
• Universal Neonatal Foot Orthosis (UNFO) demonstrates excellent results, with 87% of moderate-to-severe cases achieving significant improvement when applied for 23 hours daily 3
• Both static and dynamic orthoses show effectiveness, though dynamic orthoses may provide better functional outcomes in heel position and passive foot motion 2

Rigid/Non-Flexible Deformities

Serial casting 1, 4

• Reserved for rigid deformities that cannot be passively corrected
• Apply plaster casts changed at regular intervals
• Only 1-2% of cases present with truly rigid deformity requiring this approach 1

Timing Considerations

Treatment is most effective when initiated before 9 months of age 4. Early diagnosis through routine orthopedic examination of all newborns prevents misdiagnosis and allows optimal treatment timing 1. The average age at treatment initiation in successful cases is approximately 6.6 months (range 4-11.5 months) 3.

Treatment duration with orthoses typically continues until complete correction is achieved, followed by gradual weaning, with follow-up maintained until at least walking age 3.

Surgical Options (Reserved for Treatment Failures)

Metatarsal osteotomy is considered only for severe adult cases or pediatric cases unresponsive to all conservative measures 5. In adults, osteotomy near the metatarsal base with internal fixation using AO small-fragment cancellous screws has shown success 5.

Expected Outcomes and Complications

Conservative treatment achieves correction in approximately 87-96% of cases when initiated early 3, 1. Minor complications occur infrequently, primarily superficial skin ulcerations that resolve within one week 3, 1. No significant functional limitations persist in successfully treated cases, with excellent scores on functional rating systems at long-term follow-up 2.

Common Pitfalls to Avoid

• Delaying treatment beyond 9 months of age significantly reduces effectiveness 4
• Misclassifying severity can lead to under-treatment of rigid deformities or over-treatment of flexible ones 1
• Discontinuing orthotic treatment prematurely before complete correction increases recurrence risk 3
• Failing to ensure proper orthotic fit can cause pressure sores, particularly important in any patient with compromised sensation 6