Foot and Ankle

rearfoot - talus, calcaneus
midfoot - navicular, cuboid, 3 cuneiform
forefoot - metatarsals, phalanges

to bear weight
promote stability, but also mobility depending on functional needs
respond to forces from the ground and imposed forces from joints above

dorsiflexion/plantar flexion
inversion/eversion
abduction/adduction

proximal tibiofibular joints
distal tibiofibular joint
talocrural joint (ankle)
talocalcaneal joint (subtalar)
transverse tarsal joint (talonavicular and calcaneocuboid joint)
5 tarsometatarsal joints
5 metatarsophalangeal joints
9 interphalangeal joints

plane, synovial joint with convex tibial facet and concave fibular facet
joint capsule, ant and post tibiofibular ligaments

syndesmotic joint - concave tibia and convex fibula
no joint capsule, but many ligaments
interosseous membrane, ant and post tibiofibular ligaments

stability: ligaments responsible for maintaining stable mortise, fibular will provide mobility for function of these joints

synovial hinge joint - concave distal tibia, convex talus
fibula extends more on the lateral side than the tibia on the medial side - therefore doesn't lie in 1 axis so very hard to isolate movements

anterior talofibular (resists plantarflexion), posterior talofibular (resists dorsiflexionn), calcaneofibular (control inversion)
control inversion of the ankle/talus
weaker, more susceptible to injury
supports the talocrural and subtalar joints

limits anterior translation of the talus
ankle sprains!

anteriorly
dorsiflexion

deltoid ligament
medial malleolus -> nevicular, talus, calcaneus
controls eversion and abduction of the ankle/talus - extremely strong
supports talocrural and subtalar joints

articulation between the talus and calcaneus
posterior - concave talus convex calcaneus
anteiror - convex talus, concave calcaneus
cervical ligament

subtalar joint

talonavicular (medial): anterior talus and navicular
calcaneocuboid (lateral): anterior calcaneus and cuboid

plane, synovial joint
distal row of tarsals posteriorly, bases of the metatarsals anteriorly
1st metatarsal and medial cuneiform
2nd metatarsal and middle cuneiform
3rd metatarsal and lateral cuneiform
4th and 5th metatatsals and cuboid

many ligamentous supports: deep transverse metatarsal ligament (keeps the metatarsals from spreading)

condyloid with 2 DoF: flexion/ext, ab/adduction
convex metatarsal heads, concave bases of proximal phalanges
all metatarsal heads bear weight in stance
2 seasamoid bones at the first metatarsal

joint capsule
plantar plates
collateral ligaments
deep transverse metatarsal ligament

act as a pulley for FHB, and protext FHL

synovial hinge joints with one degree of freedom: flex/ext

smooth the weight shift to the opposite foot in gait
help maintain stability by pressing against the ground in standing

DF: 0-20 deg
PF: 0-50 deg

DF/PF
inversion/eversion
ab/adduction

limited dorsiflexion compared to plantarflexion
as the talus glides posteriorly, tighter fit
more likely to see ankle sprains in positions of PF and inversion

posterior glide of talus
muscle length of gastroc
posterior glide of distal fibula
anterior glide of proximal fibula

soft tissue structures:
medial and lateral ankle ligaments
active or passive tension in which muscles
bony end feel not common

extension - lengthened across the knee, passively insufficient

weight bearing

swing

AP axis - inversion/eversion
vertical axis - adduction/abduction
horizontal/ML axis - DF/PF (slightly)
-first 2 in equal parts

pronation/supination

movement of the calcaneus on a relatively stationary talus and lower leg
supination - calcaneal adduction, inversion, and PF (calcaneal varus)
pronation - calcaneal abduction, eversion, and DF (calcaneal valgus)

pronation -> Tibial IR, Talar add and pf, calcaneal eversion -> arch flatters
supination -> Tibial ER, Talar abd and df, calcaneal inversion -> arch lifts

excessive pronation to increase DF
Tibia IR
increased Q angle
valgus
hip IR or adduction

transitional link between rearfoot and forefoot
adds to pronation/supination ROM at subtalar joint
compensates the forefoot for rearfoot position and movement

-basically opposite of what subtalar joint is doing in order to keep the foot on the ground
-useful when on uneven ground, ability to twist through the midfoot so that the rear and forefoot can do separate movements

augment the function of the TTJ
regulate position of the metatarsals and phalanges in relation to WB surface
-like a backup to TTJ when inadequate to accomodate the forefoot

allow the WB foot to roate over the toes through MTP extension - metatarsal break
push off in late phase of gait - particularly first MTP joint

significantly reduces step length
most noticable right before toe off

medial longitudinal arch
lateral longitudinal arch
transverse arch

need to serve both contrasting mobility and stability
need to be mobile in order to dampen the impact of WB forces, superimposed rotational motions, and adapt to changes in surfaces
also need stability and to allow distribution of weight for conversion of a flexible foot to a rigid level for push off

arch support

tightens plantar fascia
heel and MTP are drawn closer together
arch is raised
contributes to supination for rigid lever for push off in gait

basically extending the big toe makes the foot arch

gastroc
soleus
tibialis posterior
FDL
FHL
all can plantarflex the ankle
also helps with postural control

peroneus longus, brevis, tertius - PF
EDL - DF
- all evert the foot

tibialis anterior
EHL - 2 joint muscle

weight bearing tasks
even supporting the arches in static standing

fractures
tendinopathies
plantar heel pain
lateral ankle pain