METATARSUS ADDUCTUS

 

METATARSUS ADDUCTUS

 

DEFINITION:

A skeletal disorder characterized by adduction and invesion of the metatarsal bones resulting in in-toeing.

EPIDEMIOLOGY:

  • incidence: 2/1000 live births
  • age of onset:
    • newborn
  • risk factors:
    • associated with congenital dislocation of the hips in 2-10% of cases

PATHOGENESIS:

1. Background

1. Metatarsus Adductus

  • due to an in utero positional deformity
  • a flexible deformity - the forefoot can be brought into the neutral position
  • spontaneous resolution in 90% of cases by 3 months of age
  • may be bilateral or unilateral
  • also may involve contractures of the medial soft tissues of the foot

2. Metatarsus Varus

  • due to in utero subluxation
  • a fixed deformity
  • does not correct spontaneously after birth
  • may be bilateral or unilateral
  • also involves medial subluxation of the tarsometatarsal joints

CLINICAL FEATURES:

1. Pedal Manifestations

  • the forefoot (metatarsals) is held in varus relative to the hindfoot, i.e., the forefoot is rotated inwardly
  • the lateral border of the foot is convex while the medial border is concave
  • a line bisecting the heel passes lateral to the 2nd and 3rd toes (this line normally passes between the 2nd and 3rd toes)
  • increased web space between the great and 2nd toes
  • prominent base of the 5th metatarsal
  • the heel and hindfoot are in a normal position with easy passive dorsiflexion at the ankle

INVESTIGATIONS:

1. Skeletal X-Rays

  • not necessary for the diagnosis

MANAGEMENT:

1. Supportive

  • passive stretching exercises with each diaper change
  • if the deformity persists past 3 months refer to an Orthopedic Surgeon for passive manipulation and casting as these are corrective is most patients
  • operative correction of a simple metatarsus deformity is not appropriate as no long term disability persists

 

 

 

Pediatric Database - METATARSUS ADDUCTUS

Pediatric Organization - Pedbase [at] Gmail.com