Pes Cavus

Synonym: Clawfoot
This is a foot with a very high arch, which does not flatten on weight-bearing.¹ May be cavovarus or cavovalgus.

This condition is caused by an imbalance between the agonist and antagonist muscles in the foot. There is often family history and it is usually bilateral.
One in five cases are idiopathic, but most are associated with neurological disorders.²

• Unilateral:
  • Cerebral palsy
  • Spinal cord tumour
  • Spina bifida
  • Tethered cord
• Bilateral:
  • Congenital
  • Polio
  • Charcot-Marie-Tooth syndrome³
  • Becker muscular dystrophy
  • Friedreich's ataxia

Also associated with clubfoot or fractures.

There is often a range of other foot deformities also present e.g. claw toes, increased calcaneal angle, 'cocked-up' big toe.

Symptoms

Varies with degree of deformity:

• Pain in side of foot and metatarsals
• Calluses on plantar aspect of foot
• Instability of ankle

Signs

• Inspect shoes for signs of abnormal wear
• Observe gait for varus, foot drop
• Perform neurological examination for possible underlying cause

Take a full family history.

• X-ray of foot
• MRI of spine if tumour suspected
• Electromyography

Non-Drug

• Physiotherapy to loosen tight muscles and improve strength of weak ones.
• Padding and orthotic shoes.

Surgical

• Depending on nature of deformity can be release of plantar fascia, tendon transfer, osteotomy and arthrodesis.²
• Many need several operations.