foot and ankle Flashcards
foot & ankle complex (28) bones
- 1 tibia / 1 fibula
- 1 talus / 1 calcaneus
- 1 cuboid / 1 navicular / 3 cuneiforms (5 tarsal bones)
- 5 metatarsals
- 14 phalanges
t/n: these all forms 25 joints in one extremity
proximal tibiofibular joint
- superior tibia + fibula
- “forgotton joint”
- SYNOVIAL PLANE joint type
t/n: is called “forgotten joint” because it is often neglected by clinicians/anatomists alike
distal tibiofibular joint
- inferior tibia + fibula
- SYNDESMOSIS joint type (allows small movements/slightly movable fibrous joint)
t/n: only allows small movements/slightly movable fibrous joint as they are connected by CONNECTIVE TISSUE
everything about (3) regions of the foot
1) hindfoot
- clue: HIDE / asa likod / POSTERIOR segment
- formed by (4) bones: fibula / tibia, talus / calcaneus
2) midfoot
- clue: MIDDLE / asa gitna / MIDDLE segment
- formed by (5) TARSAL bones
3) forefoot
- clue: FORWARD / asa harap / ANTERIOR segment
- formed by METATARSALS and PHALANGES
talocrural joint
- formed by ankle mortise
- comprised of (3) bones: tibia / fibula / talus/talar bone
- HINGE joint type (DF+PF)
talocrural joint - ankle mortise
lateral & medial malleoli
t/n: lateral malleoli (distal protrusion of fibula) / medial malleoli (extending inferior part of tibia)
talocrural joint CPP & OPP
CPP
- full dorsiflexion
OPP
- 10 deg plantarflexion
- midway between inversion & eversion
talocrural joint - everything about TALUS
- trochlea = proximal aspect of body of talus
- (3) articulations’:
1) lateral (larger) malleolar facet / fibula
2) medial (smaller) malleolar facet / tibia
3) superior (dome) facet / tibia inferior aspect
talocrural joint - lateral malleolus
- distal extensions of tibia and fibula
- more DISTAL (protruding) and POSTERIORLY (situated) > tibial torsion
talocrural joint - tibial torsion
- external tibial torsion / tibiofibular torsion
- causes toe-out in normal standing
talocrural joint - toe-out angle
- “fick’s angle”
- (2) normal values:
1) adult = 12-18 deg
2) children = 5 deg
t/n: quick check up if toe-out is normal, look at person posterior view, if you see only 3 toes = normal, if more than 3 toes = not normal, excessive ER of tibia
talocrural joint - talocural axis
- obliquely oriented
- normal values = 14 deg (from horizontal axis)
t/n: because of anatomical structure of tibia and fibula/shape of tc joint, talocrural axis is not completely horizontal > DF and PF happen uniaxially
talocrural joint - DOF
- 1 DOF
- DF/PF
talocrural joint - WB vs NWB motions
NWB
- DF w/ EV
- PF w/ INV
WB
- DF w/ INV
- PF w/ EV
clue: alphabetically arranged first (ev comes first before inv)
t/n: this is d/t inclined/obliquely-oriented axis (~14 deg)
subtalar joint
- “talocalcaneal joint”
- formed by TALUS and CALCANEUS (below ‘sub’ talus)
- PLANE joint type
t/n: complex type of joint because of articulating surfaces’ SHAPE being HIGHLY VARIABLE
subtalar joint - sinus tarsi (anatomy & function)
- houses proprioceptive center
- location of mechanoreceptors > provides proprioceptive info on ankle and foot
- proprioceptors: deep sensory receptors
*** - ANTERIOR to LATERAL malleolus
- tunnel lies LAT to MED side
- SMALL END lies BELOW TIBIAL MALL
subtalar joint - tarsal canal
- located LATERAL aspect of FOOT
- TUNNEL FUNNEL-SHAPED running OBLIQUELY
- LARGE
subtalar joint - sustentaculum tali
- a BONY prominence
- palpable close to SMALLER END of sinus tarsi
t/n: important to palpate to know where sinus tarsi is
transverse tarsal joint
- “midtarsal joint” “choparts joint” “surgeon’s joint”
- s-shaped
- combination of (2) joints:
1) calcaneocuboid
2) talonavicular/talocalcaneovicular - allows ABD/ADD of FOREFOOT
transverse tarsal joints - motions
- supination and pronation (tri-planar axes)
t/n: this is caused by the oblique axis of the joint by 57 deg (sagittal), 52 deg (transverse superiorly)
transverse tarsal joint - supination and pronation
1) supination
- combination of ADD, INV, PF
2) pronation
- combination of ABD, EV, DF
transverse tarsal joint composite motions (NWB vs WB)
NWB
- supination
- calceneal ADD
- INV
- PF
- pronation
- calcaneal ABD
- EV
- DF
WB (calcaneus is fixed/proximal segments are the one moving)
- supination
- calcaneal INV
- talar ABD
- talar DF
- tibiofib ER
*pronation
- calcaneal EV
- talar ADD
- talar PF
- tibiofib IR
tarsometatarsal joint
- articulation of TARSALS (cuboid/cuneiform) and METATARSALS
- PLANE SYNOVIAL joint type
tarsometatarsal joint (3) capsule sharing & articulation
1) 1st = own capsule / medial cuneiform
2) 2nd & 3rd = share capsule / middle cuneiforms (med, mid, lat)
3) 4th & 5th = share capsule / cuboid
tarsometatarsal joint (2) twisting motions
1) supination twist
- hindfoot pronation
> medial forefoot ground / lateral side lift > 1st and 2nd ray DF / 4th and 5th PF
- entire foot inversion ROT at tarsometatarsal
2) pronation twist
- reverse
t/n: this is to keep entire foot on the ground (if there’s a problem w/ WB supi / prona of transverse tarsal)
metatarsophalangeal joint
- formed by metatarsal (convex) and proximal phalanges (concave)
- SYNOVIAL CONDYLOID joint type
- 2 DOF: FLEX / EXT, ABD / ADD
- has 3 metatarsal variations
metatarsophalangeal joints - 3 metatarsal variations
1) index plus
- 1st metatarsal longer
2) index minus
- 2nd metatarsal longer
3) index plus-minus
- 1st and 2nd metatarsals equal in length, longer than others
metatarsophalangeal joint - metatarsal break
- mtp extension during walking (normal)
metatarsophalangeal joint - hallux rigidus vs hammer toe
hallux rigidus
- rigid hallux
- interferes w/ metatarsal break
- there is not much extension happening in the joint
hammer toe
- excessive EXT of MTP / FLEX of IP
- both PROXIMAL and DISTAL
- does not influence metatarsal break
- places TOO MUCH PRESSURE on metatarsal head > SKIN breakdown
interphalangeal joint (joint type & DOF)
- SYNOVIAL HINGE joint type
- 1 DOF: FLEX / EXT (sagittal plane)
(4) tibiofibular joints ligaments
1) crucial tibiofibular interosseous ligament
2) tibiofibular interosseus membrane
3) anterior / posterior tibiofibular ligament
- supports both proximal and distal tbf joint
- these structures are affected w/ HIGH ANKLE SPRAINS (syndesmotic injuries)
t/n: sprains often occur at the level of malleoli, but with these ligaments may be affected when we have sprain above malleoli (high ankle)
(2) talocrural joint ligaments
1) lateral collateral ligament (LCL)
2) medial collateral ligament (MCL)
talocrural joint - (3) LCL bands and its MOI
1) anterior talofibular ligament (ATFL)
- WEAKEST ligament (fibers spread out)
- MOI: excessive INV / foot PF
- affected in this position because of ANT/HORIZONTAL orientation
2) posterior talofibular ligament (PTFL)
- RARELY torn
- MOI: ext ROT of foot / DF
- located POSTERIOR/BEHIND foot
3) calcaneofibular ligament (CFL)
- MOI: excessive INV / neutral position (between DF & PF), sometimes DF
- located MORE LAT
talocrural joint - MCL
- “deltoid” ligament
- fan-shaped orientation of fibers
- MAIN FUNCTION is to RESIST excessive EV / VALGUS force
- stronger / least injured than LCL because of (4) BANDS
t/n: they are not widely spread like LCL > eversion injuries LESS COMON
talocrural joint - (4) MCL bands
1) anterior tibiotalar ligament (ATTL)
2) posterior tibiotalar ligament (PTTL)
3) calcaneotibial/tibiocalcaneal ligament (CTL)
4) tibionavicular ligament
subtalar joint (4) ligaments
1) calcaneofibular ligament
- part of your LCL
2) lateral talocalcaneal ligament
- provide LATERAL STABILIZATION on SUBTALAR
3) cervical ligament
- STRONGEST among 4
4) interosseus talocalcaneal ligament
- found between TALUS and CALC
t/n: they serve as LATERAL support (superficial to deep) / relies more on BONE CONFIG than ligaments for STABILITY
transverse tarsal joint - spring / plantar calcaneonavicular ligament
- talonavicular joint
- main passive stabilizer of MEDIAL longitudinal arch
- MOST IMPORTANT LIG. on the MEDIAL side of the foot
transverse tarsal joint (4) calcaneocuboid ligaments
1) bifurcate/calcaneocuboid ligament
- lateral support
2) dorsal calcaneocuboid ligament
- dorsal support
3) plantar calcaneocuboid ligament
- plantar support
4) long plantar ligaments
- plantar support
- supports LATERAL longitudinal arch
t/n: lateral side hence support LATERAL side of the foot
ankle and foot (3) muscle compartments
1) anterior
2) posterior
3) lateral
ankle and foot (4) muscles of ANTERIOR compartment
1) tibialis anterior “primary dorsiflexor”
- DF / INV
2) extensor digitorum long. “secondary dorsiflexor”
- DF (2 deg) / EXT toes
3) extensor hallucis “secondary dorsiflexor”
- DF (2 deg) / EXT big toe
4) peroneus tertius “weak dorsiflexor
- DF / EV
- only evertor of the ANT. comp (insert towards LAT. aspect of foot)
ankle and foot (3) muscles of POSTERIOR SUPERFICIAL compartment
1) gastrocnemius “double-jointed”
- 2 heads: medial & lateral
- influenced by knee pos
- active / passive insufficiency
2) soleus “single jointed”
3) plantaris “fisherman’s nerve”
- weak plantarflexor
ankle and foot POSTERIOR SUPERFICIAL comp - triceps surae
- gastrocnemius & soleis
- “TRI” because gastrocs has 2 heads
ankle and foor (3) muscles of POSTERIOR DEEP compartment
1) flexor digitorum longus “pf/weak invertor of the foot”
2) flexor hallucis longus “pf/weak invertor of the foot”
3) tibialis posterior “invertor par excellence”
- PRIMARY/MAJOR muscle for INV
- DEEPEST muscle of POST. compartment
ankle and foot (2) muscles of LATERAL compartment
1) peroneus/fibularis longus
- PF / EV
2) peroneus/fibularis brevis
- PF / EV
t/n: considered plantarflexors even evertors (tendons located posterior to axis of ankle PF & DF movements of foot)
(2) foot intrinsics compartments
1) dorsal compartment
2) plantar compartment
ankle & foot (1) muscle of DORSAL compartment
1) extensor digitorum brevis
- ONLY muscle in the DORSAL compartment
- sends fibers on MEDIAL FOUR toes TO AID in EXT of toes
> extensor hallucis brevis
- part of EDB
- most medial fiber of EDB
ankle & foot (4) layers of muscles of PLANTAR compartment
1st layer
1) ABD HALL
2) ABD DIGI MINI
3) FLEX DIGI BREV
2nd layer
1) LUMBRICALS
2) QUAD PLANT / FLEXOR ACCESSORIES
3rd layer
1) ADD HALL
2) FELEX DIGI MINI
3) FLEX HALL BREV
4th layer (deepest layer)
1) INTEROSSEI
2) (7) DORSAL / (3) PLANTAR
(3) plantar arches of the foot & function
1) medial longitudinal arch
2) lateral longitudinal arch
3) transverse arch
- normally flat in children below 5 yrs old (flatfootedness)
- integrated to ENHANCE DYNAMIC function of the foot
> have MOBILITY / STABILITY function in WB stance
> for MOBILITY, adapt to VARIOUS SURFACE SHAPES during EARLY STANCE phase
> for STABILITY, arch makes foot MORE RIGID to allow WEIGHT distribution
medial longitudinal vs lateral longitudinal vs transverse arch (keystone, passive support, etc.)
medial longitudinal arch
- keystone: talus/navicular
- DYNAMIC support by EXTRINSIC / INTRINSIC muscles of the foot
- PASSIVE support by SPRINGlig., INTEROSS. TALOCALC lig., DELTOID lig., PLANTAR aponeurosis
lateral longitudinal arch
- keystone: cuboid
- PASSIVE support by LONG & SHORT PLANTAR lig.
transverse arch
- keystone: middle cuneiform
- PASSIVE support by DEEP TRANSVERSE MATATARSAL lig.
plantar aponeurosis
- plantar fascia
- keeps the INTEGRITY of all 3 ARCHES
- generates TENSION that PREVENTS ARCHES from COLLAPSING
t/n: they come from MEDIAL TUBERCLE of CALCANEUS > plantar plates > proximal phalanx of each toe
plantar aponeurosis - windlass effect
- tension bought by MTP hyperEXT.
- produces TENSION of PLANTAR FASCIA
- DRAWS hindfoot & MT TOGETHER
- CONTRACTS intrinsic muscles
- RAISES longitudinal arches
t/n: beneficial during gait (push-off) > aponeurosis taut > calceneus pulled anteriorly > achilles tendon stretch > gastrocs contract > propel foot forward
pes planus
- hyperpronated foot “foot flatednes”
- limits MTP EXT.
- increased TENSION in PLANTAR AP
- windlass effect DECREASED
plantar fascitis
- INFLAMMATION of plantar fascia
- common condition with FLAT-FOOTED people
- PAIN felt during FIRST STEP in the morning
- common areas: heel / front of calcaneus / middle long. arch
foot & ankle weight distribution
- trabecular system
- 100% weight from HEAD, LEG, TRUNK, UPPER PART OF LEG > received by TALUS
- talus distributes 50% EQUAL > CALCANEUS (POSTERIOR) > MID & FOREFOOT (ANTERIORLY)
t/n: plantar pressure in QUIET stance is distributed EQUALLY to hindfoot and forefoot. walking and running even produce STRONGER pressure
