Cavus foot (High arches)

  • Cavus foot

    The basic cause of a cavus foot is an imbalance between the inward pulling (inverters) and outward pulling (evertors) muscles. The inverters are strong compared to the evertors. It is the opposite of a flat arch.

    Causes

    Many cases are neurological starting at an early age and getting progressively worse with age. One entity is the Charcot Marie tooth syndrome.

    Unlike a flat foot, a cavus foot can present with a single or multiple foot deformities. The tendons behind the heel (tendoachilles) are invariably tight. Claw toes/hammer toes, calluses, metatarsalgia occur, with resulting forefoot pain.

    High arched foot (cavus)
    High arched foot (cavus)
    X ray showing cavus and a downward bend in                  
                                                                                      midfoot
    X ray showing cavus and a downward bend in midfoot

    Treatment

    Is tailor-made to suit the deformity and symptoms that are presented. Extra depth and broad shoes are prescribed in most cases. Metatarsal bars and inserts are used to relieve pressure on the ball of toes.

    Some patients will require an AFO (ankle foot orthrosis)- a light weight thermoplastic material to support weakened evertors.

    AFO for weak muscles
    AFO for weak muscles
    AFO for weak muscles
    Pictures of foot before and after surgery 

    Surgery

    Is almost invariably required.

    • Releasing tight heel tendons
    • Tendon transfers to stabilize the invertors and evertors
    • Correction of claw/hammer toes
    • Mid-foot closing wedge osteotomy
    • Calcaneal displacement osteotomy

      Calcaneal osteotomy and mid-foot osteotomy

      Calcaneal osteotomy and mid-foot osteotomy
    • Triple fusion in an unstable ankle

      Triple fusion in an unstable cavus foot

      Triple fusion in an unstable cavus foot

    Triple fusion is done either with multiple screws, as shown above in the picture, or with nails. Either way, total time for complete ankle fusion is 6 to 12 weeks.