Pes Cavus Flashcards
pes cavus is a result of what
- several structural and/or positional abnormalities
- may be congenital or developmental in origin
does the term “cavus” and “pes cavus” indicate etiologies
NO! is purely descriptive
pes cavus deformities are primarily in what plane
sagittal plane
is pes cavus only an isolated sagittal plane deformity
no
what 2 deformities are likely to result in pes cavus
- inverted calcaneus (frontal plane deformity) may result with a high arch foot type
- rigid FF valgus (frontal plane deformity) is likely to compensate via STJ supination and appear as a pes cavus foot type
how may a pes cavus foot function
either pronated or supinated
how can a pes cavus be classified
fixed or functional
can pes cavus be equated with a supinated foot type
NO!
Can occur in a pronated foot
how will a FF varus with a cavus foot deformity compensate
- pronation
- high arched, pronated foot type
radiographic findings can help differentiate between what type of pes cavus
supinated vs. structurally high arched foot
describe a lateral view of a supinated foot
- increased calcaneal inclination angle
- decreased talar declination angle
- posteriorly displaced cyma line
- plantar deviation of Meary’s line
- increased stair-step effect on MTs
- bullet hole sinus tarsi
describe a DP view of a supinated foot
- decreased talocalcaneal angle
- FF adducted on the RF
- increase FF/MT overlap
describe the lateral view of a high ached foot w/o supination
- increased calcaneal inclination angle
- decreased talar declination angle
- normal Meary’s line
- normal cyma line
- normal relationship of the MTs
describe a DP view of a arched foot w/o supination
- no FF or metatarsal adduction
- normal talocalcaneal angle
- normal relationship of the MTs
what are the different ways a pes cavus foot can be categorized
- location of deformity (apex of the deformity - high point of arch)
- co-existing deformities (ie. frontal and transverse plane deformities)
- method of compensation
- etiology
what are the different pes cavus based on location
- anterior cavus
- posterior cavus
- combined cavus
what are the different types of anterior cavus
- metatarsus cavus
- lesser tarsus cavus
- forefoot cavus
describe the appearance of a metatarsus cavus (anterior cavus)
- the apex of the deformity is located as Lis Franc’s joint
- dorsal prominence may be palpated at that joint, particularly in the area of the 1st metatarsocuneiform joint
- the talus, navicular and cuneiforms will all be collinear
clinical appearance/symptoms of metatarsus cavus
- high instep
- 1st metatarsocuneiform exostosis
- shoe fitting is difficult (may be limited to low cut shoes; orthotic therapy is difficult due to limitations in shoe gear)
- normal cuboid angulation
- pseudoequinus may lead to pronation
- claw toes with anterior displacement of the fat pad plantar to the MT heads
describe the appearance of a lesser tarsus cavus (anterior cavus)
- the lesser tarsal bones are in a plantarflexed attitude
- a generalized dorsal prominence may be noted in the lesser tarsal area
what is a variant of a lesser tarsus cavus foot
plantarflexed 1st ray
describe the appearance of a FF cavus (anterior cavus)
- FF is plantarflexed at Chopart’s joint
- RF will appear to be in a dorsiflexed position
- dorsal prominence of the talar head may be present immediately anterior to the medial malleolus noted on an off-weight bearing exam (as a result of anterior impingement which may lead to bony equinus)
- navicular, cuboid, 4th and 5th MTs are plantarflexed to the RF as compared to normal
what are 2 radiographic findings of a FF cavus
- increased calcaneal inclination angle
- increased MT declination angle
what are symptoms of FF cavus
- calcaneal apophysitis in children (decreased contact surface of the calcaneus)
- claw toes
FF Cavus Variants
- plantarflexed cuboid with plantarflexed 4th and 5th MTs
- a high arched pronated foot
- actually a type of FF varus
Radiographic findings of FF Cavus Variants
- an increased calcaneal inclination angle but no FF adduction (lateral view)
- ANTERIORLY displaced cyma line (lateral view)
- increased plantar declination of the cuboid (lateral view)
- wider talo-calcaneal angle (DP view)
- plantarflexed and adducted talus (lateral view)
symptoms of FF cavus variants
- a sagittal linear crease may be found btwn the 3rd and 4th MTs
- keratoma sub 2nd, 4th/5th MT heads
- adductovarus contractures 3rd, 4th and 5th digits
- Tailor’s Buion
- postural fatigue
- HAV
what are other FF Cavus Variants
- plantarflexed cuboid with dorsiflexed 4th and 5th MTs (more common that a plantarflexed cuboid w/ plantarflexed 4th and 5th MTs)
- no pronation is required for compensation
- if pronation is present it is as a result of other influences
clinical findings of FF Cavus Variants
- plantar prominence of the styloid process of the 5th MT
- increased arch.increased calcaneal inclination angle but no adduction of the FF
- may cause apophysitis at the 5th MT base
- Tailor’s bunion/splat foot appearance (secondary to dorsiflexed 5th ray)