Flashcards in 16_ Mechanics of foot and ankle Deck (32):
What helps stabilize the ankle joint (tibiotalar joint)?
1. deltoid ligament
2. anterior talofibular ligament
3. calcaneofibular ligament
4. posterior talofibular ligament
What comprises the deltoid ligament?
1. tibionavicular, ant/post tibiotalar, tibiocalcaneal ligament.
* very strong and bone Fx occurs before the ligament tears*
What is the first ligament to tear with an inversion sprain?
anterior tibiofibular ligament
What are the major ankle motions?
1. Plantar flexion of 50 degrees.
2. Dorsiflexion up to 20 degrees.
What are the accessory motions of the ankle?
side-to-side glide, rotation, abduction and adduction with plantaflexion
When is the ankle most stable?
What osseous structures help form the motion of the hind foot?
1. Combined motion of talocalcaneal, talonavicular, and calcaneocuboid joint
What will inversion of the foot do structurally?
1. Increase the height of medial arch.
2. Rotate cuboid down on calcaneus
3. Is increased with plantar flexion
Inversion can also be best described as how?
calcaneal adduction, navicular rotation, and talus glide
What will eversion of the foot do structurally?
1. lateral rotate calcaneus and navicular
2. decrease medial arch height.
3. cuboid rotate up on calcaneus.
4. is exaggerated with dorsiflexion
Eversion can best be described as how?
calcaneal abduction, navicular rotation, talus glid.
* raise the lateral portion of foot and depress the medial portion*
What are features of the lateral arch? (structure, actions)
1. calcaneus, 4th5th meta, cuboid.
2. limit mobility. strong base for transfer of weight/thrust into the ground
What are structure and action of the medial arch?
1. More mobile, without firm osseous support, allowing adaptation to terrain.
2. Calcaneus, 1,2,3 metatarsal, cuneiforms, navicular
Which arch helps to control gait?
What causes a high medial arch?
adduction of foot and varus calcaneus
What causes a dropped medial arch?
Abduction of foot and valgus calcaneus and dorsiflexion
What forms the metatarsal (anterior) transverse arch?
1. metatarsal heads
2. Transmit weight to the ground, and flattens with weight bearing.
What forms the posterior metatarsal arch?
What forms the tarsal arch?
navicular, cuboid, and cuneiforms.
*allows rotation and flexibility of foot*
What causes flat foot (pesplanus)?
loss of the tarsal arch (pesplanus)
What are you looking for on evaluation of the ankle?
1. edema, swelling, discoloration, callus, weight distribution, position of toes, arch height, achille's tendon, bone deformities.
If the Achille's tendon bows, it is indicative of what?
1. pronated feet, with the affected side
Describe a hammer toe.
felxion deformity of the PIP and extension deformity of DIP
Describe the claw toes.
Flexion deformity with PIP and DIP joint flexion.
1st medial deviation of metatarsal with lateral deviation of proximal phalanx of hallux.
*Causes tenderness on MTP and erythematous*
Subtalar abduction and adduction occurs where?
subtala, talonavicular and calcaneocuboid joints.
Calcaneal inversion/eversion motion testing.
1. pt active motion first.
2. Passive mvmt by grabbing calcaneus, and locking talus by gripping forefoot with other hand.
Describe steps in stance phase of gait
1. heel strike
2. foot rolls to lateral edge
3. weight rolls back to anterior transverse arch
4. great toe pushes off.
Grade 1 acute inversion sprain.
microtear in ligament, with swelling and disability but no laxity (instability)
Grade 2 acute inversion sprain.
partial ligament tear, with swelling, mild instability, antalgic gait, laxity with a good end point and decrease ROM
Grade 3 acute inversion sprain.
Complete tear, with no endpoint and loss of function and instability