Dorsum of the Foot

Question 1

the interosseous talocalcaneal ligament blends with the attachment of the medial root of inferior extensor retinaculum. This ligament forms a sling around what structures?

Answer 1

tendons of the extensor digitorum longus and peroneus tertius muscles

Question 2

the superomedial oblique band of the inferior extensor retinaculum passes superficial to what structures?

Answer 2

1. tendon of extensor hallucis longus
2. anterior tibial artery and vein
3. deep fibular nerve

Question 3

after passing the extensor hallucis longus tendon, the superomedial oblique band of the inferior extensor retinaculum fuses with the deep layer to form a tunnel for what structure?

Answer 3

tendon of tibialis anterior

Question 4

the inferomedial oblique band of the inferior extensor retinaculum passes superfcially to what structures?

Answer 4

1. dorsalis pedis artery
2. deep peroneal nerve
3. tendons of extensor hallucis longus
4. tendon of tibialis anterior

Question 5

Where does the superolateral oblique band of the inferior extensor retinaculum attach medially? what about the inferomedial oblique band?

Answer 5

superolateral- attaches on the anterior surface of medial malleolus

inferomedial- attaches to plantar fascia, navicular tuberosity, and medial cuneiform

Question 6

what are teh extensor expansions formed by?

Answer 6

tendons of the extensor digitorum longus and brevis muscles

Question 7

what is the only intrinsic muscle to the dorsum of the foot?

Answer 7

extensor digitorum brevis

Question 8

O/I for extensor digitorum brevis?

Answer 8

(only intrinsic muscle to the dorsum of the foot)
Origin- tubercle on the superolateral surface of calcaneus anterior to sinus tarsi, from the interosseous talocalcaneal ligament and from the frondiform ligament
Insertion- lateral surface of the tendons of the extensor digitorum longus muscle of the 2nd, 3rd, 4th digits distal to the MPJ (and extensor hallucis brevis inserts on the dorsal surface of the base of the proximal phalanx of the 1st digit)

Question 9

innervation of extensor digitorum brevis?

Answer 9

lateral terminal branch of deep peroneal nerve

Question 10

what is the saphenous nerve a branch of?

Answer 10

a sensory branch off the femoral nerve

Question 11

where does the saphenous nerve run anatomically?

Answer 11

runs on the medial side of the leg, coursing laterally along the great saphenous vein, and enters the dorsum of the foot anterior to the medial malleolus

Question 12

what surfaces in the foot does the saphenous nerve innervate?

Answer 12

skin along the medial side of the foot as far as the base of the 1st met

Question 13

the sural nerve continues as what in the foot as it courses the lateral side of the foot?

Answer 13

lateral dorsal cutaneous nerve of the foot

Question 14

the lateral dorsal cutaneous nerve gives off a branch- what is it?

Answer 14

the 10th dorsal digital nerve that supplies the lateral side of the 5th toe

Question 15

what are the 2 terminal branches of the superficial peroneal nerve?

Answer 15

intermediate and medial dorsal cutaneous nerve

Question 16

what does the medial dorsal cutaneous nerve give rise to?

Answer 16

1st dorsal digital nerve and

1st common dorsal digital nerve

Question 17

where does the 1st dorsal digital nerve arise from? where does the 10th dorsal digital nerve arise from?

Answer 17

1st –> from medial dorsal cutaneous nerve

10th –> from lateral dorsal ctuaneous nerve

Question 18

where do the 2nd and 3rd dorsal digital nerves arise from?

Answer 18

medial terminal branch of the deep peroneal nerve

Question 19

Where do the 4th and 5th dorsal digital nerves arise from?

Answer 19

1st common dorsal digital branch

Question 20

the deep peroneal nerve has a lateral and medial terminal branch? what does each do?

Answer 20

lateral terminal branch- passes deep to extensor digitorum brevis and innervates it

medial terminal branch- (found w/ DP artery); divides into 2 dorsal digital nerves in the 1st intermetatarsal space

Question 21

what is the arterial supply for extensor digitorum brevis?

Answer 21

lateral tarsal artery (off of the dorsalis pedis artery)

Question 22

in which toe interspace does the 1st common dorsal digital nerve go t?

Answer 22

second toe space (in btwn digits 2 and 3)- gives off the 4th and 5th dorsal digital nerves

Question 23

what gives rise to the 2nd common dorsal digital nerves?

Answer 23

intermediate dorsal cutaneous nerve

Question 24

Where does the 3rd common dorsal digital nerve come from?

Answer 24

intermediate dorsal cutaneous nerve

Question 25

What artery continues into the dorsum of the foot as the dorsalis pedis artery?

Answer 25

anterior tibial artery

Question 26

what are the terminal branches of the dorsalis pedis artery?

Answer 26

deep plantar artery | 1st dorsal metatatarsal artery

Question 27

describe the path the dorsalis pedis artery takes, in relation to other structures.

Answer 27

The tendon of the extensor hallucis longus follows the artery distally along its medial side, while the extensor digitorum longus can be located along its lateral side. At its distal end, it is crossed by the tendon of the extensor hallucis brevis.

Question 28

what relationship does the dorsalis pedis artery have in relation to extensor hallucis longus and extensor digitorum longus?

Answer 28

extensor hallucis longus- lies medial to DP artery | extensor digitorum longus- lies laterally

Question 29

the blood supply to the dorsum of the foot is provided by which branches of the DP artery?

Answer 29

1. lateral tarsal 2. medial tarsal 3. arcuate 4. 1st dorsal metatarsal 5. deep plantar

Question 30

what is the largest branch of the dorsalis pedis artery?

Answer 30

lateral tarsal artery | *arises at the neck of the talus

Question 31

where, and with which artery, does the lateral tarsal artery anastamose with?

Answer 31

passes below the tendon of the peroneus brevis to anastomose with the lateral plantar artery

Question 32

what muscle does the lateral tarsal artery supply?

Answer 32

extensor digitorum brevis

Question 33

what artery provides vascular supply to the head and the neck of the talus?

Answer 33

proximal part of the lateral tarsal artery

Question 34

what does the medial tarsal artery supply?

Answer 34

medial aspect of tarsal bones and terminate by contributing to the medial malleolar rete

Question 35

on the lateral side fo the foot, what does the arcuate artery anastomose with?

Answer 35

lateral tarsal and lateral plantar arteries

Question 36

which branches does the arcuate artery give rise to?

Answer 36

2nd, 3rd, and 4th dorsal metatarsal arteries | *note that the 1st dorsal metatarsal artery is a terminal branch of the dorsalis pedis

Question 37

how many dorsal metatarsal arteries are there? name the origin of each.

Answer 37

4: the first is from the dorsalis pedis directly | - the 2nd, 3rd and 4th dorsal metatarsal are branches of the arcuate artery

Question 38

how many common digital nerves are there? name the origin of each.

Answer 38

3: the first common digital nerve is from the medial dorsal cutaneous n. (and goes to the 2nd interspace) - the 2nd and 3rd common digital n. is from the intermediate dorsal cutaneous n. (and goes to the 3rd and 4th interspace)

Question 39

where does the 1st dorsal digital artery arise from?

Answer 39

the medial branch of the 1st dorsal metatarsal artery

Question 40

what artery gives rise to the 2nd and 3rd dorsal digital artery?

Answer 40

the lateral branch of the 1st dorsal metatarsal artery

Question 41

At the proximal end of the interosseous spaces, the dorsal metatarsal arteries receive perforating branches from where?

Answer 41

posterior perforating branches of the plantar arch

Question 42

At the distal end of the interosseous spaces, the dorsal metatarsal receive branches from where?

Answer 42

anterior perforating branches of the plantar metatarsal arteries

Question 43

after receiving distal (anterior) perforating arteries , the dorsal metatarsal arteries are known as what?

Answer 43

common dorsal digital arteries

Question 44

which dorsal digital arteries does the first dorsal metatarsal artery supply?

Answer 44

dorsal digital arteries 1 to 3

Question 45

what gives off the 10th dorsal digital artery?

Answer 45

either directly from the lateral part of the arcuate artery or from the 4th dorsal metatarsal artery

Question 46

what does the deep plantar artery anastamose with/

Answer 46

first plantar metatarsal artery of the deep plantar arch

Question 47

the dorsal digital veins of the foot unite with the plantar digital veins to form what?

Answer 47

dorsal metatarsal veins

Question 48

describe the general pathway of the venous system for the dorsum of the foot.

Answer 48

dorsal digital veins --> dorsal metatarsal veins --> dorsal venous arch --> medial/lateral marginal vein --> great saphenous/ small saphenous vein

Question 49

what forms the lateral marginal vein?

Answer 49

lateral dorsal digital vein of the 5th toe (aka 10th dorsal digital vein) + lateral end of the dorsal venous arch

Question 50

what is the medial marginal vein formed by?

Answer 50

medial dorsal digital vein of the 1st toe (aka 1st dorsal digital vein) and the medial end of the dorsal venous arch

Question 51

what does the medial marginal vein give rise to?

Answer 51

great saphenous vein

Question 52

what does the lateral marginal vein give rise to?

Answer 52

small saphenous vein

Question 53

the deep fascia divides the dorsum of the foot into 3 layers arranged from superficial to deep. What is in each layer?

Answer 53

1st layer- tibialis anterior, extensor hallucis longus, extensor digitorum longus and peroneus tertius 2nd layer- extensor digitorum brevis 3rd layer- dorsalis pedis artery, deep peroneal nerve, veins, and the termination of perforating branch of peroneal artery

Question 54

what are the attachments for superior extensor retinaculum?

Answer 54

laterally: distal end of fibula on its anterior border & lateral malleolus medially: anterior border of tibia & medial malleolus

Question 55

what are the lateral and medial attachments for dorsalis pedis fascia?

Answer 55

- lateral attachments: peroneal trochlea, cuboid, and tuberosity of the 5th met - medial attachments:navicular tuberosity, sustentaculum tali, and 1st met

Question 56

the superior extensor retinaculum binds which tendons in its synovial sheath?

Answer 56

extensor digitorum longus extensor hallucis longus peroneus tertius tendon of tibialis anterior

Question 57

the tendons of which muscles share teh same synovial sheath?

Answer 57

extensor digitorum longus | peroneus tertius

Question 58

how often is the superolateral oblique band of the inferior extensor retinacula present in people?

Answer 58

about 25% of people have it

Question 59

what is the function of extensor digitorum longus in terms of the extensor expansions?

Answer 59

tightens the sling and loosens the wing --> results in hyperextension of MPJ *cannot extend the IPJ bc the wing portion is loose

Question 60

what is the extensor wing? and what is it mostly formed by?

Answer 60

(distal part of the extensor hood) | -formed mostly from expansions of the tendons of the lumbrical muscles

Question 61

what is the extensor sling? what is it mostly formed by?

Answer 61

(proximal part of extensor hood) | -formed from fibers which encircle the digit and attach to the plantar plate

Question 62

what is the function of lumbrical muscles?

Answer 62

tighten the wing and loosen the sling --> flexion in MPJ and extension in IPJ

Question 63

what is the function of the interosseous muscles?

Answer 63

act as lumbricals- flex MPJ, extend IPJ

Question 64

describe the extensor expansion of the hallux (which is different from the rest).

Answer 64

- only the tendon of the extensor hallucis longus is attached to the extensor expansion - the plantar plate is attached to the deep transverse ligament on the lateral side only - a wing and sling are present, but lumbricals and interossei do not contribute to them

Question 65

what is the perecentage of cases that an accessory peroneal branch of the superficial peroneal nerve is present that aids in innervating the extensor digitorum brevis (in addition to lateral terminal br. of peroneal n.)?

Answer 65

20%

Question 66

in which intermetatarsal space does the dorsalis pedis artery divide?

Answer 66

1st intermetatarsal space.

Question 67

trace the course of the DP artery. what is the % of time the DP can be found in this path?

Answer 67

(75%) trace DP distally across talus, navicular, intermediate cuneiform, and the base of the 2nd met to the 1st intermetatarsal space

Question 68

what percentage is the DP artery deviated to the medial or lateral side?

Answer 68

10% of cases

Question 69

in what % of individuals is the diameter of the artery smalller in size?

Answer 69

5-10%

Question 70

what percentage of time is the anterior tibial artery absent? then where does the DP arise from/

Answer 70

(5%)- DP usually originates from the perforating branch of the peroneal artery

Question 71

what % of cases does teh arcuate artery originate from the dorsalis pedis artery at the level of the first tarsomeatarsal joint?

Answer 71

65% | *in other cases, its origin can be slightly more proximal