Pes Cavus

Radiographic findings typically include:

  • DP View
    • decreased talocalcaneal angle
    • normal or decreased cuboid abduction angle
    • increased forefoot adductus angle
    • increased talonavicular joint "congruency"
  • Lateral View
    • decreased talar declination angle
    • increased calcaneal inclination angle
    • increased 1st metatarsal declination angle
    • posterior break in the cyma line
    • "bullet hole" sinus tarsi

Etiology

  • idiopathic
  • acquired
  • neuromuscular disease
  • congenital

Here are some examples of pes cavus followed by interpretations (*):

  • Case 1a
  • Case 1b
  • *Case 1a
  • *Case 1b
  • Case 2
  • *Case 2
  • Case 3a
  • Case 3b
  • *Case 3a
  • *Case 3b
  • Case 4a
  • Case 4b
  • *Case 4a
  • *Case 4b
pes cavus dp
pes cavus lateral
pes cavus dp marked

DP view. Findings include a decreased talocalcaneal angle and normal cuboid abduction angle; the forefoot and metatarsus adduction angles are increased. Talonavicular joint "congruency" is nearly 100%. Diagnosis: pes cavus.

pes cavus lateral marked

Lateral view. Findings include increased calcaneal inclination and 1st metatarsal declination angles; the talar declination angle is decreased. The cyma line is "broken" posteriorly. Meary's and Hibbs' angles apex at the 1st and 2nd metatarsophalangeal joints, respectively. Diagnosis: pes cavus (metatarsus/LisFranc cavus).

lesser tarsus cavus
lesser tarsus cavus marked

Lateral view. Findings include increased calcaneal inclination and 1st metatarsal declination angles; the talar declination angle is decreased. The cyma line is minimally "broken" posteriorly, and the "bullet-hole" sinus tarsi is plainly visible. Meary's and Hibbs' angles apex at the naviculocuneiform joints. Diagnosis: pes cavus (lesser tarsus cavus).

chopart cavus dp

Medial oblique view. Findings include union between the anterior calcaneal process and the navicular bone (arrows). (C = calcaneus; N = navicular) Diagnosis: calcaneonavicular bar.

chopart cavus lateral
chopart cavus dp marked

DP view. Findings include a decreased talocalcaneal angle and normal cuboid abduction angle; the forefoot and metatarsus adduction angles are increased. Talonavicular joint "congruency" is nearly 100%. Diagnosis: pes cavus.

chopart cavus lateral marked

Lateral view. Findings include increased calcaneal inclination and 1st metatarsal declination angles; the talar declination angle is decreased. Meary's and Hibbs' angles apex at the talonavicular joint. Diagnosis: pes cavus (Chopart cavus).

polio dp leftpolio dp right
polio lateral left polio lateral right
polio dp left marked polio dp right marked

Dorsoplantar views. The right foot demonstrates angular relationships that are in contrast to the left foot. This patient has a history of polio.

polio left lateral markedpolio lateral right marked

Lateral views. The right foot (bottom) demonstrates angular relationships that are in contrast to the left foot. This patient has a history of polio.

Should a radiographic study be ordered for evaluation of pes cavus?

Yes, if symptomatic.

What are the best views to order?

At a minimum, order dorsoplantar and lateral views.

When should additional imaging studies be ordered?

CT or MRI may be useful for preoperative planning.

Other Information

Assessing the pes cavus foot is complex and not limited to radiographs alone. The radiographic findings must be correlated to clinical findings for detemination of fixed versus flexible deformity and if any compensatory features.

Meary's and Hibbs' "angles" are used to assess the location of an anterior cavus deformity based upon the apex of each angle. This is then correlated to the clinical picture.

References:

  1. Christman RA: Foot and Ankle Radiology, 2nd edition, Lippincott Williams & Wilkins, 2015.