The clinical presentation is consistent with pediatric flexible pes planovalgus, or flatfoot. The vast majority of these cases are asymptomatic and do not require treatment, and Level 1 evidence shows no benefit with corrective orthotics. In rare situations when nonoperative treatments fail to relieve pain under the head of the talus or in the sinus tarsi, surgery is indicated. A calcaneal lateral column lengthening osteotomy (Evans procedure) is the procedure of choice. Illustration A shows a line depicting the long axis of the talus and a line following the long axis of the 1st metatarsal. The angle between the 2 lines is referred to as Meary's angle and a plantar apex angle of greater than 4 degrees indicates collapse of the longitudinal arch. Illustration B shows an example of a normal Meary's angle and pes planus foot with a Meary's angle of 12 degrees. All of the other options are used in the treatment of pes cavus deformities.
The Level 1 investigation by Wenger et al concludes that wearing corrective shoes or inserts for three years does not influence the course of flexible flatfoot in children. They recommend observation as the best conservative management option.
Wenger DR, Mauldin D, Speck G, Morgan D, Lieber RL. Corrective shoes and inserts as treatment for flexible flatfoot in infants and children. J Bone Joint Surg Am. 1989 Jul;71(6):800-10.
PMID: 2663868 (Link to Abstract)
Staheli LT. Foot. In: Staheli LT, ed: Practice of Pediatric Orthopaedics, 2nd ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2006:105-142