biomechanics of ankle and foot Flashcards
dorsiflexion and plantarflexion; eversion and inversion degrees
20 df
50 pf
35 inversion
15 eversion
Talocrural joint is between which segments
Leg and rear foot
Transverse tarsal joint is between
rear foot and mid foot
Tarso metatarsal joints are between
Mid foot and forefoot
Rear foot includes
Talus calcaneus
Subtalar joint
mid foot includes
navicular, cuboid, cuneiforms
Transverse arch
Medial longitudinal arch
forefoot
metatarsals phalanges
proximal tibiofibular joint
Planar synovial joint with capsule
tibia convex fibula concave
Accommodates motion occurring at ankle
motion- Superior/inferior glide and AP oblique glide
Tibiofibular joint during ankle dorsiflexion
Fibula laterally rotates and moves superior posterior
tibiofibular joint during knee flexion and extension
Flexion- anterior glide
Extension - posterior glide
distal tibiofibula joint
fibrous syndesmosis
Concave tibia , convex fibula
Maintain a stable ankle mortise
Talocrural joint
synovial
Modified sellar or hinge joint uniaxial
1° of freedom dorsiflexion and plantarflexion
talocrural joint open and close positions
open- 10° plantar flexion
Close - end range dorsiflexion
talus and mortice shape
convex talus
concave mortise (plafond)
does talus have muscular attachment?
no
limited blood supply too
capsular pattern limitations
We will have a loss in plantarflexion before we have a loss in dorsiflexion
ligamentous support for the talocrural joint
lateral- anterior and posterior talofibular, calcaneofibular
medial- deltoid (tibionavicular, ant and post tibiotalar, and tibiocalcaneal)
subtalar joint
three joints
Modified ovoid functioning as a modified sellar
Three separate facet articulations- posterior, middle and anterior
1° of freedom, inversion and eversion
(some add/abd and slight PF DF)
subtalar joint open and close positions
open- neutral pronation/supination and 10 degrees of pf
close- supination
capsular pattern of subtalar joint
varus limitations > valgus
ligamentous support subtalar joint
internal- cervical ligament, interosseous talocalcaneal lig
extrinsic- calcaneofibular lig, deltoid lig
function of subtalar joint
Triplanar motion- pronation supination
Accommodates rotational force between leg and foot
Maintains foot contact with ground during stance
calcanal iv/ev > midfoot pronation/supination
Transverse tarsal joint
midtarsal or choparts joint
taloNavicular joint
calcaneocuboid joint
talonavicular joint
part of transfers tarsal joint
concave- navicular
convex- talus
Deep condyloid
iv/ev and df/pf
talonavicular and spring ligaments
calcaneocuboid joint
part of transverse tarsal joint
saddle joint
Forms interlocking wedge that resists gliding of the joint
Provide stability to lateral column
dorsal calcaneocuboid ligament, bifurcate lig, long/short, plantar ligaments
Motion of transverse tarsal joint
two oblique axes
primary- longitudinal or AP axis; IV/EV
secondary- oblique axis; ABD/ADD and PF/DF
Open and close position of transverse tarsal joint
Open- midpoint of pronation/supination and 10° of plantarflexion
close- full supination
subtalar and transverse tarsal joint work together for
Composite motions of supination and pronation
subtalar joint in supination reduces
Mobility of midfoot
subtalar joint in pronation increases
Mobility of midfoot
tarsometatarsal joints
synovial planar joints
Lisfranc joint
Degrees of freedom -flexion/ extension, sup/pron
Functions to keep contact with ground
closed position and open position of Tarsometatarsal joints
Open- midpoint of sup/pronation
close- full supination/ extension
ray 1 & 2
iv/df
ev/pf
ray 3
df/pf
ray 4&5
ev/df
iv/ pf
metatarsophalangeal and interphalangeal joints
synovial condyloid
degrees or freedom- 2 flex/ext and add/abd
capsular pattern-
MTPs ext> flex
IP flex> ext
close and open metatarsophalangeal and interphalangeal joints
Open- neutral, slight flex
Close - full extension
ligamentous support for MTP and IP
collateral ligaments
Plantar plates
Transverse metatarsal ligaments
sesamoids
Sit under the first metatarsal head
pulley for flexor hallucis brevis
Flexor Hallucis longus tendon passes between the sesamoids, which offers some protection on the base of the foot