Foot

Question 1

dorsum foot muscles

Answer 1

-extensor digitorum brevis
-extensor hallucis brevis
-innervation- deep fibular nerve
-blood supply- dorsalis pedis artery
-assist the extensor longus muscle with extending the toes (MP and IP joints)

Question 2

blood supply to anterior leg compartment

Answer 2

-anterior tibial artery (one of terminal branches of popliteal artery)
-after branching from popliteal artery -> passes through gap in superior part of interosseous membrane to enter the anterior compartment of leg
-courses inferior on anterior surface of interosseous membrane between tibialis anterior and extensor digitorum longus muscles
-when anterior tibial artery courses ankle joint -> becomes dorsalis pedis artery that supplies dorsal foot
-arcuate branch forms arch across foot that gives rise to dorsal metatarsal arteries -> ultimately dorsal digital arteries

Question 3

dorsalis pedis artery

Answer 3

-evaluated when performing PE of peripheral vascular system
-farthest palpable vessel from heart
-palpated between tendons of extensor hallucis longus and extensor digitorum longus

Question 4

motor/sensory innervation: superficial fibular nerve

Answer 4

-motor innervation in lateral compartment
-courses between fibularis longus and brevis to provide them with innervation along its path

-sensory innervation- at distal third of leg -> pierces deep fascia to enter the superficial fascia where it becomes cutaneous nerve
-cutaneous nerve continues its course inferiorly to supply distal third of lateral leg and dorsum of foot

Question 5

motor/sensory innervation deep fibular nerve

Answer 5

-motor- innervates muscles in anterior compartment of leg as well as extensor brevis muscle in dorsal foot
-sensory- innervates small cutaneous region located at webspace between 1st and 2nd toes

Question 6

cutaneous innervation: dorsal foot

Answer 6

-superficial fibular nerve- most of dorsal foot
-deep fibular nerve- supplies webspace between 1st and 2nd toes
-medial- saphenous nerve
-lateral- sural nerve

Question 7

foot drop

Answer 7

-results from complete paralysis of foot dorsiflexor muscles
-paralysis results in toe pointing (dropping) towards the floor when raising foor off the ground during walking
-to life their foot higher off the ground to prevent dragging of toes -> pt compensates by increasing knee flexion
-alteration in gait -> steppage gait

Question 8

foot slap

Answer 8

-results from weakness (paresis) of foot dorsiflexor muscles (partial foot drop)
-when heel strikes ground during walking, weakness of dorsiflexor muscles results in inability to slowly lower the foot to the ground -> results in an audible slapping of the foot against the ground

Question 9

most common cause of foot drop/slap

Answer 9

-due to compression of neuron fibers within the common fibular (peroneal) nerve or deep fibular (peroneal) nerve as it courses within the anterior compartment

Question 10

neurological causes of foot drop include the following conditions

Answer 10

-charcot marie tooth disease
-diabetic neuropathy
-multiple sclerosis

Question 11

tarsal bones

Answer 11

-calcaneus- calcaneus tuberosity and sustenaculum tali (talar shelf)
-talus- head and neck
-navicular
-cuboid
-cuneiforms- medial, intermediate, lateral
-metatarsals 1-5
-phalanges- proximal, middle, and distal

Question 12

foot regions

Answer 12

7 tarsals, 5 metatarsals, 14 phalanges
-3 anatomical and functional groups:
-hindfoot- talus and calcaneous
-midfoot- navicular, cuboid, and cuneiforms
-forefoot- metatarsals and phalanges

Question 13

calcaneal (achilles) tendons

Answer 13

-attaches to calcaneal tuberosity
-narrow space between anterior surface of the calcaneal tenon and superior part of posterior surface of calcaneal tuberosity is occupied by retrocalcaneal bursa
-irritation/inflammation of retrocalcaneal bursa, or of subcutaneous calcaneal bursa (achilles bursa) can cause pain at heel and ankle

Question 14

microscopic tears of collagen fibers of calcaneal tendon

Answer 14

-result in tendinitis
-can ultimately lead to calcaneal tendon rupture
-steroids (systemically or injected) around tendon -> increase probability of calcaneal tendon rupture

Question 15

distal tibiofibular joint

Answer 15

-distal tibia and fibula are held tightly together by interosseous membrane and the anterior and posterior tibiofibular ligaments
-syndesmotic sprain (high ankle sprain)- injury to distal tibiofibular syndesmosis with possible disruption of distal tibiofibular ligaments and interosseous membrane

Question 16

subtalar and transverse tarsal joints

Answer 16

-subtalar joint- articulation between inferior surface of the talus and the superior surface of calcaneus
-transverse tarsal joint- consist of 2 joints:
-talonavicular- articulation between talus and navicular bone
-calcaneocuboid joint- articulation between calcaneus and the cuboid

Question 17

deltoid ligament

Answer 17

-fibrous capsule of ankle is fairly weak -> must rely on ligaments to provide support
-deltoid ligament (medial collateral) - fan shaped ligament whose apex is located on medial malleolus of tibia and attaches to navicular, talus, calcaneus
-strong ligament and functions to prevent excessive range of motion (primarily eversion)
-has 4 parts:
-tibionavicular ligament
-tibiocalcaneal ligament
-anterior tibiotalar ligament
-posterior tibiotalar ligament

Question 18

plantar fascia and plantar foot muscles

Answer 18

-plantar fascia- deep fascia of sole of the foot
-plantar aponeurosis- thickened central portion of fascia which spans distance between calcaneus and toes

Question 19

plantar fasciitis

Answer 19

-joggers heel, tenis heel, policemans heel
-most common cause of heel pain
-caused by repetitive microtrauma to plantar fascia

Question 20

plantar foot muscle: layer 1

Answer 20

-abductor hallucis- medial plantar artery
-flexor digitorum brevis- medial and lateral plantar artery
-abductor digiti minimi- lateral plantar artery
-abductor hallucis and flexor digitorum brevis innervated by medial planar nerve
-abductor digiti minimi innervated by lateral plantar nerve
-abductor hallucis- abducts and flexes 1st digit (big toe)
-flexor digitorum brevis- flexes lateral 4 digits
-abductor digiti minimi- abduct and flexes 5th digit (little toe)

Question 21

plantar foot muscles: layer 2

Answer 21

-intrinsic plantar foot muscles
-quadratus plantae- lateral plantar nerve
-lumbricals- medial 1- medial plantar nerve; lateral 3- lateral plantar nerve
-both supplied by medial and lateral plantar artery
-quadratus plantae- assists in flexor digitorum longus with flexing lateral 4 digits
-lumbricals- flex proximal phalanges, extend middle and distal phalanges of lateral 4 digits

Question 22

plantar foot muscles layer 3

Answer 22

-flexor hallucis brevis
-adductor hallucis- transverse and oblique heads
-flexor digiti minimi brevis
-medial and lateral plantar nerves and arteries

Question 23

medial and lateral sesamoids of foot

Answer 23

-located within the 2 tendons of flexor hallucis brevis muscle
-sesamoids function to increase mechanical advantage of flexor hallucis brevis, assist in weight bearing and determine the line of action of the flexor hallucis longus muscle
-disruption of sesamoids leads to disruption of normal functioning of metatarsophalangeal joint

Question 24

plantar foot muscles layer 4

Answer 24

-intrinsic foot muscles consist of 2 groups of muscles that abduct and adduct the toes
-both innervated by lateral plantar nerve:
-dorsal interossei
-plantar interossei

Question 25

hallux valgus

Answer 25

-bunion
-deformity
-may be caused by pressure from improperly fitted footwear or degenerative joint disease
-characterized by lateral deviation of the great toe
-L in vaLgus -> lateral

Question 26

foot arches

Answer 26

-2 types of foot arches: longitudinal and transverse
-longitudinal arch- medial and lateral longitudinal arch
-transverse arch- half arch lying inferior to forefoot and between lateral and medial longitudinal arches

Question 27

longitudinal arch

Answer 27

-medial longitudinal arch- largest and most clinically significant -> located from proximal to distal along the medial aspect of foot
-lateral longitudinal arch- lies from proximal to distal along the lateral aspect of foot and is more shallow that medial arch

Question 28

weight bearing areas of foot

Answer 28

-located at anterior and posterior aspect of longitudinal arches
-these are calcaneal tuberosity -> heads of 2nd-5th metatarsals and the sesamoid bones of the 1st metatarsals

Question 29

dynamic and passive support of arches

Answer 29

-arches are formed by tarsal and metatarsal bones- supported by foots ligaments and tendons
-dynamic support of longitudinal arch is provided by intrinsic foot muscles in sole of foot as well as tibialis posterior, tibialis anterior, and flexor hallucis longus muscles
-passive support provided by plantar aponeurosis, short plantar ligament, long plantar ligament, and plantar calcaneonavicular (spring) ligament
-spring ligament- important bc it supports head of talus at peak of medial longitudinal arch of foot

Question 30

acquired flat feet

Answer 30

-fallen arches
-inferomedial displacement of head of talus
-most likely to be secondary to dysfunction of tibialis posterior muscle

Question 31

blood supply to plantar foot

Answer 31

-posterior tibial artery enters foot inferior to medial malleolus through the tarsal tunnel
-after passing through tunnel it bifurcates into 2 vessels
-medial plantar artery- courses through foot along the medial edge of abductor hallucis
-lateral plantar artery- courses between quadratus plantae and flexor digitorum brevis muscles
-distally in foot -> vessel curves medially to form deep plantar arch
-arch supplies blood to metatarsals and phalanges via plantar metatarsal arteries and plantar digital arteries
-termination point of arch is where it joins with deep plantar artery -> terminal branch of dorsalis pedis artery

Question 32

innervation of plantar foot

Answer 32

-tibial nerve- enters foot inferior to medial malleolus through tarsal tunnel
-branches:
-medial calcaneal nerve- branches from tibial nerve within tunnel -> provides sensory innervation to posterior and plantar heel
-terminal branches:
-medial plantar nerve- motor to intrinsic foot muscles and sensory to medial region of plantar aspect of foot
-lateral plantar nerve- motor to intrinsic foot muscles and sensory to lateral region of plantar aspect of foot

Question 33

lateral and medial plantar nerves

Answer 33

-often compromised in diabetic pts
-loss of sensation to feet along with poor blood flow -> render these pts susceptible to development of foot ulcers
-foot ulcers are undetected and untreated
-can lead to infection and possibly the need to amputation
-most amputation a re preventable with regular care and proper footwear

Question 34

achilles tear

Answer 34

-left calf and ankle pain
-going out to lunge
-snap -> calcaneal tendon (watershed area)
-irregular mass in posterior calf
-diffculty doing plantar flexion
-easier time with dorsiflexion bc no opposing pull
-Tomson’s test- squeeze gastrocnemius muscles look for flexion -> if no flexion -> tendon tear

Question 35

plantar fascitis

Answer 35

-running for long times
-persistent
-anterior to calcaneal tuberosity

Question 36

which ligaments maintain the longitudinal arch of foot

Answer 36

-posterior tibial ligament
-intrinsic plantar ligaments
-people with drop foot/slap have large arch