Cavovarus Foot M21.6X9 736.75

 

synonyms:

Cavovarus Foot ICD-10

Cavovarus Foot ICD-9

  • 736.75 Cavovarus deformity of foot, acquired
  • 736.76 Other calcaneous deformity

Cavovarus Foot Etiology / Epidemiology / Natural History

  • often seen in conjunction with Charcot-Marie-Tooth disease
  • May present in childhood or adulthood.  May result from muscle imbalance. 
  • 1/3 normal familial variant; 2/3 progressive neuroligc disorder (Younger AS, JAAOS 2005;13:302)
  • Associated neurologic disorders: Charcot=marie=tooth (CMT), cerebral palsy, Friedreich's ataxia, Huntington's chorea, Lou Gehrig's disease, Occult hydocephalus, peripheral neuropathy, polio
  • Hindfoot varus deformity can lead to overload of the lateral foot with: lateral ankle instability, peroneal tendinosis, 5th metatarsal stress fracture, medial malleolar fracture.

Cavovarus Foot Anatomy

  • .

Cavovarus Foot Clinical Evaluation

  • Pt ambulates on the lateral side of her foot.
  • May cause complaints of lateral ankle instability. (Manoli A, Foot Ankle Int 2005;26:256).
  • Determine if deformity is flexible or rigid; static or progressive.
  • Evaluate for neuromotor disease.
  • Coleman Block test: 

Cavovarus Foot Xray / Diagnositc Tests

  • A/P, Lateral, and Mortise Ankle and A/P, Oblique, Lateralfoot xrays indicated. Llateral radiograph shows forefoot equinus and parallelism between the calcaneus and talus. 
  • joints generally free of degenerative arthritis.

Cavovarus Foot Classification / Treatment

  • Mild/familial/idiopathic:  physical therapy, shoe modification.  Cushioned running shoes with equal medial and lateral stiffness without extra arch support.  Consider orthotic with recessed 1st metatarsal.  Avoid anti-pronation shoes which exacerbate the deformity.  Consider dorsiflexion osteotomy of the 1st metatarsal.
  • Forefoot driven: hindfoot deformity is flexible; varus position is related to valgus positioning of the forefoot and corrects with Coleman block test.
  • Hindfoot Driven: hindfoot deformity is fixed and does not correct with Coleman block test.  RX: calcaneal osteotomy or subtalar fusion to correct varus defomity and dorsiflexion osteotomy ofthe first ray.
  • Lateral closing wedge calcaneal osteotomy to correct the hindfoot varus, dorsiflexing osteotomy of the first metatarsal, and transfer of the peroneus longus tendon to the peroneus brevis to correct forefoot equinus.  Steindler striping is often necessary to correct the cavus deformity. (Sammarco GJ, Foot Ankle Clin 2001;6:533).
  • Arthrodesis should be reserved for joints that have degenerative changes or deformities that cannot be corrected by other means. 

Cavovarus Foot Associated Injuries / Differential Diagnosis

Cavovarus Foot Complications

  • Arthrits
  • Chronic pain

Cavovarus Foot Follow-up Care

Cavovarus Foot Review References

  1. McCluskey WP, Lovell WW, Cummings RJ: The cavovarus foot deformity: Etiology and management.  Clin Orthop 1989;247:27-37.
  2. Holmes JR, Hansen ST Jr: Foot and ankle manifestations of Charcot-Marie-Tooth disease.  Foot Ankle 1993;14:476-486
  3. Younger AS, Hansen ST Jr. Adult cavovarus foot. J Am Acad Orthop Surg. 2005 Sep;13(5):302-15