Lecture #6 (Ankle & Foot) Flashcards
What is the function of the ankle?
Unites the foot and leg
How many bones and joints are there in the ankle?
28 bones
25 joints
What are the three regions of the foot?
Forefoot, midfoot, and hindfoot
What is causes the foot position of slight external rotation when standing?
Tibial torsion
What is the normal tibial torsion?
Rotation of the tibial that occurs naturally laterally at the distal end of 20-40 degrees
What percentage of a force/load is placed on the fibula? Can this increase or decrease?
6-7%
**It can increase slightly during dorsiflexion & eversion
What is the ankle mortise?
Distal tibiofibular joint
Once the force of the body’s weight hits the talocrural joint, what happens?
50% is taken by the calcaneous and 50% is taken by the foot
What type of joint is the distal tibiofibular joint?
Syndesmosis (it has an interosseous membrane)
What are the two joints of the ankle?
Subtalar and tibio-talar (talocrural) joints
What is the open pack position for the talocrural joint? The closed packed?
Open= 10 degrees plantar flexion Closed= full dorsiflexion
What is the open packed position for the subtalar joint?
Subtalar neutral
What makes up the talocrural joint?
The articulation of the talus with the tibia and fibula (makes a mortise)
What type of joint is the talocrural joint?
Modified hinge joint
What is the orientation of the axis for the talocrural joint?
Oblique…18 degrees in the transverse plane laterally and 14 degrees in the frontal plane laterally…so it runs from superior/medial/anterior to inferior/lateral/posterior
What are the primary motions of the talocrural joint?
Plantar flexion and dorsiflexion
In what plane does dorsiflexion and plantar flexion occur in? Axis?
Sagittal plane
Horizontal axis
In what plane does ankle adduction and abduction occur in? Axis?
Transverse plane
Vertical axis
In what plane does ankle inversion and eversion occur in? Axis?
Frontal plane
A/P axis
What does dorsiflexion do to the foot?
Brings it up, slightly laterally, and longitudinally out
What does plantar flexion do the foot?
Brings it down, slightly medially, and longitudinally in
True or false:
The talus is broader anteriorly and narrower posteriorly.T
True…this is important because high ankle sprains occur during dorsiflexion because the broader talus is locked in between the malleoli. (Normal ankle sprains occur with the foot in some plantar flexion because there is a gap between the talus and the malleloi).