Infant foot deformities are generally noted at birth. They may be unilateral or bilateral. Some feet are flexible requiring only minimal treatment (often parental stretching or only one or two casts). These are sometimes termed 'positional'. More severe, increasingly rigid deformity indicates a more complex process that requires early referral. A thorough physical examination is important to identify any other abnormalities such as developmental dysplasia of the hip (DDH), spinal abnormalities or genetic syndromes. Family history should be explored to identify any relatives with similar conditions.The names of common foot deformities are usually descriptive. For example:
Forefoot adductus (a.k.a. metatarsus adductus or varus)This was discussed along with other causes of 'intoeing' earlier in the module.
Calcaneovalgus footSome authors have called this the most common infant foot deformity noting it to some degree in 30% of babies. The foot is held in a dorsiflexed position, often with the dorsum of the foot touching the anterior shin. The heel is in valgus. This deformity is flexible and resolves quickly with time. Stretching may be used; casting is rarely needed. It is important to differentiate this benign condition due to intra-uterine positioning from a more severe and rigid deformity: vertical talus. In the latter condition, the talonavicular joint is dorsally dislocated and the talar head is palpable as a firm prominence in the instep of the foot. The foot is rigid and not correctable. This condition requires surgical correction and a genetic consultation is indicated because of many associated syndromes.
|Note the forefoot adductus, heel varus and hindfoot equinus in this newborn baby with idiopathic congenital clubfoot prior to any intervention. Credit: L. Davidson
|Bilateral long leg casts applied after 'Ponseti' method manipulation. This is repeated weekly with gradual, gentle correction of deformity. In experienced hands, this treatment is effective in >80% of patients. Credit: L. Davidson