A 2-day-old male neonate born to a 28-year-old primigravida presents with bilateral inversion and plantarflexion of the feet noted at birth. On examination, the feet are held in a fixed position of inversion, adduction, and equinus. The deformity cannot be passively corrected beyond the midline. There is no associated spinal dysraphism or other congenital anomalies. What is the most appropriate initial management?