Plantar callous analysis and orthotic determination
various types and locations of the various plantar lesions is a
valuable aid in determining foot type and subsequent orthotic therapy.
There are three basic types of skin lesions (there are more)
1. Discrete (with a core) - Appearance - central core usually seen with vertical or linear stress.
2. Diffuse lesion (no central core). This usually is due to moderate shearing force as a result of biomechanical compensation.
Diffuse and enucleated - moderate to severe biomechanical
compensation and or combination of structural with
Plantar fifth callous (singular)
This lesion is seen with the following conditions:
1. Uncompensated rearfoot varus
- The entire plantar surface of the foot is inverted and the medial
side of the foot cannot bear its share of weight or may not
2. Uncompensated forefoot varus
- The calcaneus is vertical or inverted. The lateral aspect of the foot
is straight. One sees normal contact phase of gait.
3. Plantar flexed fifth metatarsal
the foot has normal range of motion and no apparent forefoot deviation,
check the fifth metatarsal range of motion If one sees
4. Fully compensated rigid forefoot valgus
this condition one sees diffuse shearing or diffuse and enucleated
lesion sub fifth metatarsal. The biomechanics of this foot
Plantar fourth callous
one sees a singular-shearing lesion under the fourth metatarsal
consider a biomechanical device. This lesion can occur as a
1. Fully compensated forefoot varus
this instance the fifth metatarsal pronates dorsally out of the way
when suppinatory movement pattern occurs early in stance phase
flexed fourth fetatarsal
a keratoma develops under a metatarsal head that seems incongruous with
forefoot angulation or excessive biomechanicss,
Metatarsal lesion sub third or second
one sees a diffuse lesion under second or third metatarsal then callous
is due to hypermobility of the second or third metatarsal.
Sub first lesion
1. Rigid compensated forefoot valgus
see a discreet lesion due to linear or vertical stress placed upon this
part early in stance phase of gait before this area is
Two or more lesions
1. Lesions first and fifth
we see lesions that are discrete and enucleated, uncompensated rearfoot
varus should come to mind. This is a higher arched
2. Nucleated callous first and diffuse lesion fifth or fourth
comes to mind is the fully compensated forefoot valgus mentioned
previously. If the fifth metatarsal can pronate out of the way,
3. Lesion sub fifth lesion sub second
lesion is commonly seen with planteflexed subfluxed fifth head
associated with hypermobile first and shearing lesion second.
4. First and second
first metatarsal exhibits discrete callous and hypermobile second. This
may be due to semirigid forefoot valgus and hypermobile
An example of this would be lesions first through fifth.
condition is commonly associated with compensated equinus. The lesions
usually are diffuse type (shearing) lesions. This patient
has been our experience at COL that many orthotic failures have been
due to inadequate balance of biomechanical versus
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I, Chao E, Johnston K. The assessment of dynamic foot-to-ground contact
forces and plantar pressure
P R, Ulbrecht J S, Caputo G M. Keynote lecture: from laboratory to
clinic: where can plantar pressure
R S. Ankle Equinus. Prevalence and linkage to common foot pathology.
Jourmal of the American Podiatry
M L, Orien W P, Weed J H. Normal and abnormal function of the foot:
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