Foot Types 2 Flashcards
what are the biomechanical foot types
Forefoot Varus Rectus Forefoot Forefoot Valgus Rearfoot Varus Rectus Rearfoot Rearfoot Valgus
when considering combination deformities, 1st figure out
where the forefoot will be related to the floor when standing in NCSP with the MTJ maximally pronated
RF Varus compensation
ground reactive forces are along the lateral side of the foot as the pt is standing in NCSP
STJ will pronate
Isolate RF Varus deformity - gait changes
- heel strike wil be inverted (normal or greater than normal amount)
- STJ will pronate to rectus or end range of pronation
- significant increase in lateral loading is likely
- medially loading may occur by plantarflexion of the medial column if inadequate STJ pronation is available to get the medial side of the foot to the ground
Isolated RF Varus Deformity - Callus patterns
- commonly sub 4th and 5th MT heads as a result of increased lateral loading
- may see a sub 5th MT base HPK if the rearfoot varus is uncompensated or minimally compensated
- may see sub 1st MT head as a result of compensatory plantarflexion of the 1st ray
Callus patterns are dependent upon
the degree of compensation available
Isolated RF Varus - shoe wear pattern
Increased wear at lateral heel
May have increased wear at 5th MT base or 4th and 5th MT heads
Isolated RF Varus - pathologies
Hallux Limitus
Tailor’s bunion
Haglund’s deformity
Hammer digit syndrome
if a 1st MTPJ deformity is going to occur, it will be
hallux limitus
Describe the cause of halux limitus
- occurs due to RF varus compensation
- calcaneus does not reach an everted position
- PL maintains its pull laterally
- 1st ray tends to remain in a stable transverse plane position
what causes Tailor’s Bunion
- occurs due to RF varus compensation
- increased loading on lateral column, GRF may force the 5th ray into a more dorsiflexed position with increased stress on the 5th MT head
Haglund’s Deformity is associated with what deformities
-increased frontal plane motion of the calcaneus around a relatively inverted calcaneal position
in a Haglund’s Deformity where does the calcaneus remain prominent
the posterior dorsal lateral corner
Hammer Digit Syndrome occurs with what digits
4th and 5th digits
Hammer Digit Syndrome is a result of
lateral column dorsiflexion for compensation
Compensation for: FF valgus = RR varus
no compensation
Compensation for: FF valgus > RR varus
LMJA supination
Compensation for: FF valgus more then 5 > RR varus
LMJA and STJ supinate
Compensation for: FF valgus < RR varus
STJ pronate
RF varus/FF valgus - Gait Changes
- calcaneus will be inverted at heel strike
- calcaneus may pronate but still remain in an inverted position
- FF may load from medial to lateral
- foot may appear adducted
- foot may be laterally unstable with MPJ collapse in late propulsive phase
when will callus patterns appear in RFVarus/FF valgus deformities
FF valgus < 5 = no HPK likely (no other deformities)
FF valgus > 5 = HPK sub 1-5
RF Varus/FF Valgus - shoe wear patterns
Increased wear at lateral heel
-increase wear generally in centre forefoot of shoe (depends on amount of FF valgus vs. FF varus
what pathologies/symptoms are associated with RF varus/FF valgus
Neuroma
Haglund’s deformity
Functional equinus (Pseudoequinus)
Plantar fasciitis (if compensation requires LMJA supination)
Ankle instability
Hallux abductovalgus (with hallux limitus or rigidus) if forefoot valgus >5
Tailor’s bunion (often associated with partially or uncompensated rearfoot varus)
RF Varus/ FF Varus - Compensation
STJ pronates enough to get the medial side of the foot down to the ground
RF Varus/ FF Varus - Gait Changes
- foot functions maximally pronate if fully compensated
- abductory twist if STJ motion is inadequate to get medial side of the FF to ground
- increased loading on the entire lateral side of the foot
RF Varus/ FF Varus - Callus patterns
- HPK sub 2nd MT head is common
- HPK sub IPJ hallux is common
- may see HPK sub 4th and 5th MT heads depending on the amount and type of compensation that is occurring
RF Varus/ FF Varus - Shoe wear paterns
- may see some exaggerated heel wear laterally, but will tend to see more medial sole wear
- may also see the heel counter in a valgus position
RR Varus/ FF Varus - Pathologies
HAV Hallux Limitus Tailor’s bunion Hammer Digit Syndrome Plantar fasciitis Forefoot Supinatus
why does HAV occur when compensating for a RR Varus/ FF Varus deformity
-everted calcaneus associated with compensation for this deformity will negatively effect the pull of the PL contributing to destabilization of the 1st ray
Rectus RR with Rectus FF - shoe wear
at heel ~ 15’ lateral to center line
Rectus RR with FF varus - compensation
STJ
if FF varus > 4-6’ STJ will pronate to max pronation
Rectus RR with FF varus - where will the heel be at stance
everted
Rectus RR with FF varus - Gait changes
- heel strike likely to be normal
- rapid and excessive pronation will be seen as the forefoot is loaded from lateral to medial
- resupination may be diminished or abset
FF Varus - callus patterns
- Hyperkeratosis sub 2nd metatarsal head and plantar hallux interphalangeal joint secondary to abnormal first ray function
- Sub 4th and/or sub 5th metatarsal heads if the forefoot varus is not fully compensated
FF Varus - pathologies?
Hallux abductovalgus and/or hallux limitus Hammer digit syndrome Plantar fasciitis Posterior tibial tendon dysfunction Equinus (chicken or the egg??)
Rectus RF with Valgus FF - compensation
Compensation
The LMJA supinates to compensate for the 1st 5 degrees of forefoot valgus deformity
The STJ supinates for the next 5 degrees of FF valgus deformity
The OMJA supinates for the next 5 degrees of FF valgus deformity
Back to the STJ if any more is required
Rectus RF with Valgus FF - Gait changes
- Heel strike will be normal
- The forefoot may load from lateral to medial or vice versa depending upon the degree of forefoot deformity
- The foot is likely to be fairly unstable in midstance as a result of LMJA supination
- If STJ supination is required for compensation, the calcaneus may remain inverted throughout stance and signs of equinus may also appear (as a result of peudoequinus)
- Late propulsive phase STJ pronation and instability is likely
Rectus RF with Valgus FF - callus patterns
- flexible FF valgus may have no callus development (no other deformities)
- may see callus patterns consistent with hypermobile 1st ray
- rigid FF valgus commonly develops HPK sub 1st and 5th MT heads
Rectus RR with FF Valgus - Pathologies
Hallux abductovalgus and/or hallux limitus
Plantar fasciitis
Haglund’s deformity (for rigid forefoot valgus)
Lateral ankle instability (for rigid forefoot valgus)
Rearfoot Valgus with No FF Deformity - Compensation
- Forefoot supination which may result in subtalar joint pronation
- Subtalar joint pronation may also occur as a result of the center of gravity being so far medial to the subtalar joint axis
- Subtalar joint supination may result, particularly if not enough MTJ supination is available to get the lateral side of the foot to the ground
Rearfoot Valgus with No FF Deformity - Gait Changes
- Calcaneus is everted to the ground at heel strike
- Loading is most likely going to occur from lateral to medial, but it may also appear as if the whole forefoot is being loaded at once
- Resupination may occur (depending on compensation), but the heel will not reach an inverted position to the ground
- May see MTJ collapse
Rearfoot Valgus with No FF Deformity - Callus Patterns
- medial heel callus (“rim” callus)
- HPK sub 2nd and maybe 3rd (result of MTJ and 1st ray hypermobility)
Rearfoot Valgus with No FF Deformity - Pathologies
“Flatfoot”
Plantar fasciitis
Posterior Tibial Tendon Dysfunction (PTTD)
Sinus Tarsi Syndrome (most commonly seen with STJ functioning max. pronated)
Cuboid syndrome (most commonly seen with STJ functioning max. pronated)
Stress fracture 2nd (sometimes 3rd) metatarsal
HAV
RF Valgus with FF Varus - Compensation
- if FF varus > RR Valgus: STJ go to end range of pronation and LMJA will be at end range of supination
- if FF varus is < RR valgus: LMJA
RR Valgus with FF Varus - describe fot
- unstable
- very flat foot
- functions maximally pronate at STJ
RR Valgus with FF Varus - Gait Changes
- Heel strike may be everted to the ground
- Forefoot is loaded rapidly and may appear to load all at once (rather than lateral to medial)
- Calcaneus is likely to remain everted throughout gait
- Generally, rather than heel lift, the whole foot will be lifted at once (APROPULSIVE)
- May be abducted angle of gait
RR Valgus with FF Varus - Callus Patterns
- medial heel callus
- may have medial 1st MT head HPK, medial IPJ hallux HPK
- may have sub 2nd MT head HPK as a result of 1st ray hypermobility
RR Valgus with FF Varus - Pathologies
Plantar fasciitis
PTTD
Sinus tarsi syndrome
Tarsal tunnel syndrome
most FF pathologies are a result of
increased stress on the FF in the propulsive phase of gait
are pathologies more or less likely with RR Valgus and FF Varus
less likely b/c this foot has no propulsive phase
RR Valgus with FF Valgus - Compensation
- A VERY DIFFICULT FOOT TYPE!
- The MTJ needs to supinate to compensate for FF and RF deformities
- This foot type often results in a very hypermobile foot with subluxation at the MTJ
RF Valgus with FF Valgus - Gait Changes
- Heel strike may be everted and may remain everted throughout gait
- Forefoot may load from medial to lateral
- Pronation of the subtalar joint into the propulsive phase of gait
- Abductory twist
RR Valgus with FF Valgus - Callus Patterns
- medial heel callus
- FF HPKs similar to isolated FF valgus patterns
RR Valgus with FF Valgus - Pathologies
HAV Tailor’s bunion 2nd metatarsal stress fracture PTTD Plantar fasciitis Sinus tarsi syndrome Tarsal Tunnel Syndrome