26 - Everted Forefoot Deformities Flashcards
Types of everted forefoot deformities
- Forefoot valgus
- Plantarflexed 1st ray
- Dorsiflexed cuboid
Forefoot valgus diagram
There are two types – flexible (total) forefoot valgus
(7 degrees) or rigid plantarflexed 1st ray
Total forefoot valgus
- Everted position of the forefoot relative to the rearfoot at the level of the MTJ.
- All of the metatarsals are on the same everted plane with one being more inferior to five
Possible etiology of total forefoot valgus
o Due to excessive frontal plane valgus torsion of the head and neck of the talus. At birth, the head and neck of the talus are in a varus rotation which quickly corrects by undergoing a valgus rotation.
o If the compensation is excessive, the MTJ everts relative to the STJ
Lateral column in total forefoot valgus
- Inversion of the lateral column of the forefoot must occur to allow the forefoot to purchase the ground during midstance and propulsion
2 forms of compensation
o Flexible(total)forefoot valgus (7°)
The compensation for a forefoot valgus follows the acronym LASSO
KNOW THIS
o LAS is MTJ longitudinal axis supination – this occurs with the flexible FF valgus
o S is STJ supination and O is MTJ oblique axis supination – These occur with rigid FF valgus (after first undergoing LAS)
LASSO o L = longitudinal o A = axis o S = supination o S = STJ supination o O = MTJ oblique axis supination
Flexible (total) forefoot valgus
- Sufficient flexibility exists within the long axis of the MTJ (LMTJ) to equal the degree of FF valgus, and allows the lateral column of the foot to reach the ground.
- Leads to severe MTJ instability during propulsion even though the heel is vertical in RCSP
RCSP in flexible (total) forefoot valgus
KNOW THIS
- The heel is vertical in RCSP*
- In flexible FF valgus, the heel remains vertical (the STJ does not need to compensate for the deformity), but the medial arch drops
Flexible (total) forefoot valgus compensation details
- All of the compensation occurs around the long axis of the MTJ
- It is a hypermobile foot because the MTJ is supinated
- We know that the supinated position of the MTJ is the unstable position of the forefoot (MTJ pronation is the stable position-cuboid locked on dorsal lip of calcaneus)
Signs and symptoms of flexible (total) forefoot valgus in the skin
o Medial heel callus
o Callus sub 2 ( 5 degrees)
o Corn 2, 4, 5 toes
Signs and symptoms of flexible (total) forefoot valgus in the muscle and fascia
o Posterior tibial strain
o Plantar fasciitis
Signs and symptoms of flexible (total) forefoot valgus in the bones
o Sinus tarsi syndrome o Cuboid syndrome o 1st met - cunei exostosis o Bunion o Tailor’s bunion o Heel spur
Signs and symptoms of flexible (total) forefoot valgus in the gait
o Abductory twist
o Late midstance pronation
o Mild lateral instability may occur
Signs and symptoms of flexible (total) forefoot valgus in the foot type
KNOW THIS
**Severe flatfoot **
This means there will be strain on the MEDIAL ankle structures
Rigid (total) forefoot valgus
- If the amount of FF valgus is > 7 degrees, the LMTJ cannot fully compensate.
- STJ supination occurs first.
- If this is insufficient to get the lateral column to the ground, the OMTJ supinates.
RCSP in rigid (total) forefoot valgus
KNOW THIS
Heel is in varus in RCSP
This leads to a HIGH ARCH
Signs and symptoms of rigid (total) forefoot valgus in the skin
o Lateral heel callus
o Callus sub 1 & 5
o Corn 4 & 5 toes
LATERAL instability present
Signs and symptoms of rigid (total) forefoot valgus in the muscle or fascia
o Plantar fasciitis
o Achilles tendonitis
o Functional equinus
Signs and symptoms of rigid (total) forefoot valgus in the bones
o 1st met - cunei-exostosis o Hallux limitus o Increased shock in gait o Retrocalcaneal exostosis o Heel spur
Signs and symptoms of rigid (total) forefoot valgus in the gait
o Normal progression
o Resupination at midstance
Signs and symptoms of rigid (total) forefoot valgus in the foot type
*KNOW THIS
Stable cavus
LATERAL INSTABILITY
Two types of deformities seen with a plantarflexed 1st ray
- Structural
- Positional
Structural deformity - plantarflexed first ray
KNOW THIS
- AKA rigid plantarflexed 1st ray
- Congenital
- Cavus foot
- Difficult to dorsiflex 1st metatarsal head to level of 2nd metatarsal head with manual pressure with STJ neutral – lesser meta heads are on the same parallel plane
- 1st ray R.O.M. is normal (10 mm), but more in plantarflexion.
- RCSP of varus (compensates just like a rigid FF valgus)