Pes Planus / Pes Cavus

The Arches of the Foot

Heel and metatarsal heads are the prinicple weight-bearing points
Bones of the foot are arranged in
1. two longitunial arches:
  - Medial arch: calcaneus, talus (apex), navicular, 3 cuneforms; 3 medial metatarsals
  - Lateral arch: calcaneus, cuboid, lateral 2 metatarsals
2. transverse arch

The arches are maintained by:
1. Ligaments
  - Spring ligament - from sustentaculum tali of calcaneus to tuberosity of navicular
  - Short plantar ligament: planter surface of calcaneus to cuboid
  - Long plantar ligament: plantar surface of calcaneus to 2/3/4 metatarsals
2. Muscle tendons
  - Medial (inverters): Tibialis anterior (base 1st MT); Tibalis posterior (navicular, 3cuneiforms)
  - Latera; (everters): Peroneus longus ()
3. Interlocking bones
Ligaments are reinforced by plantar aponeurosis (condensed fascia of the sole of the foot)

Flat Feet (Pes Planus)

Loss of the longitudinal arch of the foot
Usually associated with mild valgus deformity of the hind foot; results in pronation of the forefoot and subsequent loss fo the medial arch
All children are flat-footed when they walk, arch develops when they are more active
Infantile pattern can persist into adulthood

High-arch foot (pes cavus)

Accentuation of the longitudinal arch of the foot
Secondary to muscle imablanace: relative weakness of intrinsic muscles
Associations: Charcot-Marie tooth, spina bifida, poliomyelitis
High arch clearly visible; toes always clawed (hyperextension of the metatarsophalangeal joints and flexion of the interphalangeal joints)
Patient cannot straighten their toes
Extension of the metatarsophalangeal joints and the high arch make the ball of the foot more prominent and lift the toes off the ground so they do not participate in weight bearing
Callosities develop on teh ball of the foot beneath the metatarsal bones and on the dorsal aspect of toes where they rub against shoes

Treatment options

www.surgicalnotes.co.uk