Abnormal Foot Mechanics Flashcards
When examining a patients DF what should be done at the calcaneus?
invert calcaneus as it creates a rigid lever and will avoid any oblique axis compensations (pronation)
What is the desired degrees of ankle DF in STJN?
10
Why does the foot need 10 degrees of DF in STJN during gait?
bc STJ is supinating in late midstance therefore if adequate DF is not accessible foot will begin to pronate at propulsion
What is excessive compensation?
when the motion required surpasses supportive tissue tolerance resulting in soft tissue trauma
What are two main goals during gait of foot and in what order?
- get plantar surface of calcaneus to ground by normal pronation
- get met heads to ground through forefoot
What happens to 2 goals if their is an uncompensated foot type?
RF or FF will not get into contact fully to ground
What may be a reason that pt can’t achieve either goal type?
STJ limitations, abnormal LE alignment up the chain
Can a callus pattern be diagnostic?
No, can just tell you where pts puts weight
What is normal STJ at initial contact during gait?
STJ in slight supination at HS then pronates 3-5 degrees at FF
What is normal STJ at midstance during gait?
STJ re-supinates to neutral or slight supination
What is normal STJ at propulsion during gait?
STJ continues to supinate
What are the ranges for subtalar varus?
Normal 0-4
Mild 5-6
Moderate 7-8
Severe- 9-10
Is subtalar varus more of a problem in relaxed or dynamic stance?
dynamic
What happens during gait with a compensated subtalar varus?
at IC there is increased calcaneal inversion which then leads to increased pronation to achieve goal 1-2 therefore the foot never returns to desired supination at propulsion and pushing off unstable base
What is the callus pattern for compensated subtalar varus?
2-3 met heads, MTJ unstable
Peroneus longus is unable to stabilize 1st ray so doesn’t stay down for propulsion
What are common pathologies associated with compensated ST varus?
plantar fascitis, TP tendinitis, patellafemoral dysfnx, medial knee pain, Sinus tarsai, metatarsalgia 2-3
What are treatment options for compensated subtalar varus?
control hip IR with glute work, foot intrinsics, eccentric tib post.
What are orthotic tx options for compensated ST varus?
biomehcnaical, medial rearfoot post
stability or motion control shoe
What are common characteristics of uncompensated ST varus?
hypomobile and stable foot type
What is happening during gait for an uncompensated ST varus?
increased calcaneal inversion at heel strike but there is decreased STJ motion for pronation therefore pressure remains lateral through midstance and only shift medial through heel rise
What is callus pattern of uncompensated ST varus?
lateral border of foot, 5th MET head