CMT Type 1

Commonly known as High Arch Foot. CMT type 1 is the most common subtype of CMT, accounting for roughly two-thirds of all cases.

Pes Cavus Foot

Patients with CMT experience muscle weakness, or an imbalance of muscle strength which causes a pes cavus foot. In this type of foot the arch is raised into a position that is classified as a clinical deformity.

The muscle that is responsible for this is the tibialis posterior. The forefoot adducts in what is an inward angulation. The back of the foot, or the hindfoot, usually goes into a varus position. This profile needs very careful analysis for proper correction because many times there is what we call a calcaneal varus contracture. Therefore, it is necessary to address the calcaneal varus contracture as a separate component. In these situations, we would like as much input from your physical therapist or physician as possible.

The Pes Cavus foot usually has four basic characteristics:
  • 1
    An unusually high longitudinal arch
  • 2
    Toes that are clawed
  • 3
    Prominent metatarsal heads
  • 4
    Foot is shorter than normal

CMT1 is the most commonly diagnosed type. Patients are inclined to manifest a pes cavus deformity. In addition to the foot angulation if left uncorrected, the alignment will affect the knee. Many patients find as soon as they have heelstrike with the floor, they feel their foot and knee rolling outward. As such, many patients that are affected by the pes cavus foot have a very narrow walking base. Patients have told me that other practitioners have instructed them to walk with a wider gait.

Although this sounds reasonable, it will only encourage awkwardness and more compensations by the rest of your muscles. When addressed properly, the pes cavus foot with corrected alignment will reduce fatigue, thereby allowing greater velocity and more endurance or increased walking time.

The clawing of the toes is due to a contracture of the toe extensors (4.)