- Discussion:
- calcaneovalgus (congenital calcaneovalgus) refers to flexible flatfoot in infants and young children;
- frequently seen infant foot disorder w/ forefoot abducted and the ankle severely dorsiflexed;
- mild form may be seen in upto 30% of infants but a more severe form is present in 1/000 infants;
- pathophysiology:
- common disorder presummed to be a result of intra uterine positioning;
- muscle imbalance:
- occurs as a result of flaccid paralysis or weakness of the plantarflexors;
- in myelomeningocele, there is unopposed action of the tibialis anterior and/or extensor tendons;
- Clinical Features:
- infants allow dorsiflexion to the tibia and allows full plantar flexion and inversion;
- forefoot is abducted and the ankle severly dorsiflexed;
- look for abduction of the forefoot and heel valgus;
- the plantar surface of the foot is flat, the hindfoot is in valgus position, and the forefoot is abducted;
- superficially may resemble congential vertical talus;
- when the foot and ankle are dorsiflexed, the dorsal aspect of the foot can be opposed to the anterior aspect of the tibia;
- need to distinguish calcaneovalgus from planovalgus:
- major distinguishing feature between calcaneovalgus and planovalgus is the age of onset;
- fact that heel can be dorsiflexed helps to distinguish this deformity from congential vertical talus, in which foot is stiffer & heel is in
equinus;
- anterior ankle structures may be contracted, the deformity typically is flexible & foot can passively be placed in the normal position;
- untreated neurologic cancalneovalgus feet generally have forefoot equinus, large callused heel that is prone to skin break down, and
cock up toes;
- fact that the heel can be dorsiflexed helps to distinguish this deformity from congenital vertical talus, in which the foot is stiffer and the
heel is in equinus;
- Non Operative Treatment:
- in most cases the deformity resolves without treatment;
- occasionally plantarflexion-inversion casting is used in infant if spontaneous resolution is not seen w/in first few months of life;
- orthotics are of no proven benefit;
- when there is muscle imbalance resulting from paralytic conditions, ankle-foot orthotics can control foot while child is small;
- it is impossible to quantitate what constitutes flexible flat foot;
- no device has been developed that predictably alters growth, development, or final adult configuration of a flexible flat foot;
- it is difficult to determine how much pain or excessive shoe wear should be tolerated;
- Surgical Treatment:
- results of surgery in the treatment of flexible flatfoot are extremely difficult to assess;
- it has not been proven that the mere presence of a flexible flatfoot requires any form of treatment;
- children may be candidates for tendon transfer (tibialis anterior to os calcis), &, or hindfoot stabilization by subtalar fusion is needed;
- older children may need a calcaneal elongation osteotomy in addition to tendon transfer & plantar fascia release;
- children over 10 years of age may require triple arthrodesis