ABSTRACT
Dynamic hindfoot varus (DHV) is a common presentation among children with hemiplegic cerebral palsy (Figure 29.1) and among patients of any age with stroke or traumatic brain injury, yet methods to accurately determine the source of the deformity remain unsatisfactory. Overactive or out-of-phase tibialis anterior (TA) and tibialis posterior (TP) muscles are most often cited as the cause, and surgical corrections are typically focused on these muscles (Table 29.1). TA originates on the anterior, proximal tibia and interosseus membrane, and inserts on the medial side of the medial cuneiform and on the base of the first metatarsal. It primarily serves to dorsiflex the foot while secondarily serving as an invertor of the hindfoot and supinator of the forefoot. This muscle normally acts eccentrically at initial contact to control the heel rocker prior to foot-flat, and it acts concentrically during the swing phase to dorsiflex the foot and promote ground clearance. Continuous or out-of-phase activity of TA, often seen subsequent to stroke or traumatic brain injury, is typically treated with a
split anterior tibialis tendon procedure (SPLATT), which balances the coronal plane action on the foot while preserving sagittal plane dorsiflexion.
