What does the superficial fascia contain?
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Cutaneous nerves and superficial veins.
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What does the superficial fascia contain?
Cutaneous nerves and superficial veins.
What is the function of deep fascia in the foot?
It divides the dorsum of the foot into three layers.
What structures are found in the first layer of the deep fascia?
Tendons and synovial sheaths of tibialis anterior, extensor hallucis longus, extensor digitorum longus, and fibularis tertius.
What structures are found in the second layer of the deep fascia?
Extensor digitorum brevis and extensor hallucis brevis.
What structures are found in the third layer of the deep fascia?
Dorsalis pedis artery and accompanying veins, perforating fibular artery, branches of deep fibular nerve.
What does the first dorsal digital artery supply?
It supplies the medial side of the hallux.
What does the first dorsal metatarsal artery supply?
The first dorsal interosseous muscle and first metatarsophalangeal joint (via articular branches).
Where does the deep plantar artery arise from?
From the dorsalis pedis at the proximal part of the first interosseous space.
What does the deep plantar artery join with on the plantar side of the foot?
The deep plantar arch.
What does the perforating branch of the fibular artery supply?
The anterior aspect of the leg and dorsum of the foot.
Where does the perforating branch of the fibular artery pierce?
The interosseous membrane, about 5 cm proximal to the lateral malleolus.
What are the two sets of veins in the foot?
Superficial and deep veins.
Where do superficial veins travel?
In the superficial fascia.
What is the Great Saphenous Vein a continuation of?
The medial marginal vein.
What forms the medial marginal vein?
The union of the first dorsal metatarsal vein and dorsal venous arch.
What does the first dorsal digital vein supply?
The medial side of the hallux (great toe).
What is the dorsal venous arch formed by?
The coalescence of the first through fourth dorsal metatarsal veins at the level of the metatarsal heads.
How many dorsal metatarsal veins are there?
There are four dorsal metatarsal veins.
What do the dorsal metatarsal veins drain?
They drain the adjacent sides of the toes.
What is the small saphenous vein a continuation of?
It is a continuation of the lateral marginal vein.
Where does the small saphenous vein pass in relation to the lateral malleolus?
It passes inferior/distal to the lateral malleolus.
What forms the lateral marginal vein?
The union of the tenth dorsal digital vein and the dorsal venous arch.
What does the tenth dorsal digital vein supply?
It supplies the lateral side of the fifth toe.
What do deep veins of the foot typically form?
They typically form venae comitantes, paired veins that encircle and anastomose around the arteries.
What do tributaries to the dorsalis pedis veins arise from?
They arise from the dorsal venous plexus.
Where are arteries typically located in relation to other structures?
They are usually the deepest structures, deep to retinacula, tendons, and muscles.
What should you do if you don't see the arteries during dissection?
Keep digging.
How can anatomical relationships assist in identifying structures during dissection?
They provide guidance to find and identify structures without going in blind.
What runs with the lateral tarsal artery deep to the EDB muscle?
Lateral branch of deep fibular nerve.
What is located lateral to the EHL tendon?
Anterior tibial artery and deep fibular nerve.
What runs with the dorsalis pedis artery?
Medial branch of deep fibular nerve.
What is the structure identified by the yellow arrow in the lateral view of the foot and ankle?
Superomedial oblique band of inferior extensor retinaculum.
What is the structure identified by the yellow arrow in the lateral view of the hand focusing on the extensor mechanism of a finger?
Extensor sling.
What is the structure identified as number 1 in the review questions?
Superior extensor retinaculum
What is the structure identified as number 2 in the review questions?
Superomedial oblique band of inferior extensor retinaculum
What is the structure identified as number 3 in the review questions?
Superolateral oblique band of inferior extensor retinaculum
What is the structure identified as number 4 in the review questions?
Inferomedial oblique band of inferior extensor retinaculum
What is the structure identified as number 5 in the review questions?
Frondiform ligament/stem of inferior extensor retinaculum
What is the structure identified as number 1 in the second set of review questions?
Extensor wing
What is the structure identified as number 2 in the second set of review questions?
Extensor sling
What is the structure identified as number 3 in the second set of review questions?
Medial slip
What is the structure identified as number 4 in the second set of review questions?
Lateral slip
What is the structure identified as number 5 in the second set of review questions?
Terminal slip
What is the superficial fascia of the dorsum of the foot continuous with?
The superficial fascia of the leg.
What are retinacula?
Thickenings of deep fascia that prevent bowstringing of tendons.
What is the lateral attachment of the superior extensor retinaculum?
Anterior border of fibula & lateral surface of lateral malleolus.
What is the medial attachment of the superior extensor retinaculum?
Anterior border of tibia & medial malleolus.
With which structures does the superior extensor retinaculum blend superiorly?
Crural fascia, superior fibular retinaculum laterally, flexor retinaculum & superomedial oblique band of inferior extensor retinaculum medially.
What shape is the inferior extensor retinaculum?
'Y'-shaped.
What is the stem of the inferior extensor retinaculum?
Frondiform ligament.
How many oblique bands does the inferior extensor retinaculum have?
Two oblique bands (superomedial and inferomedial).
What is the superolateral oblique band and its prevalence in the population?
It is present in 25% of people and extends from the frondiform ligament and superomedial band to the lateral malleolus, superior extensor retinaculum, and superior fibular retinaculum.
What are the three roots of the frondiform ligament?
Where does the superomedial oblique band attach?
It attaches to the anterior surface of the medial malleolus and deep fibers form tunnels for tibialis anterior and EHL tendons.
What is the attachment point of the inferomedial oblique band?
It attaches to the plantar fascia, navicular tuberosity, and medial cuneiform.
What are the extrinsic muscles involved in foot and toe extension?
Tendons of tibialis anterior, extensor hallucis longus, extensor digitorum longus, and fibularis tertius.
What is the role of the extensor hallucis capsularis tendon?
It is present on the dorsum of the hallux.
Which muscles are considered intrinsic muscles of the dorsal foot?
Extensor digitorum brevis and extensor hallucis brevis.
What do the long and short digital extensors form or insert onto?
Extensor expansions on the dorsum of toes.
How do different sources refer to the extensor digitorum brevis and extensor hallucis brevis?
They may refer to them as one or two muscles.
What is the insertion point of the Extensor hallucis brevis?
Proximal phalanx of the hallux.
Where does the Extensor digitorum brevis insert?
Extensor expansions of digits 2-4.
What is the origin of the intrinsic muscles described?
Superolateral calcaneus, anterior to the tarsal sinus.
Which nerve innervates the intrinsic muscles mentioned?
Lateral branch of the deep fibular nerve.
Does the Extensor digitorum brevis send a tendon to the 5th digit?
No, it does not send a tendon to the 5th digit.
What are the components of the extensor expansions?
Extrinsic (EDL tendons), Intrinsic (EDB tendons, Lumbrical tendons, Interossei tendons), Aponeuroses (Extensor Sling, Extensor Wing).
What is the role of the EDL tendons in the extensor expansions?
They are part of the extrinsic components.
What tendons are considered intrinsic components of the extensor expansions?
EDB tendons, Lumbrical tendons, and debated Interossei tendons.
What are the aponeuroses associated with the extensor expansions?
Extensor Sling and Extensor Wing.
How do digits 1 and 5 differ in relation to the extensor expansions?
They have different structures compared to other digits.
What happens to the EDL tendon at the MP joint for digits 2-4?
The EDL tendon divides into 3 slips.
What is the function of the central slip of the EDL tendon?
It inserts onto the base of the middle phalanx.
What do the lateral slips of the EDL tendon converge to form?
The terminal slip.
Where does the terminal slip of the EDL tendon insert?
On the base of the distal phalanx.
How does the EDB tendon interact with the EDL tendon for digits 2-4?
The EDB tendon joins the EDL tendon at or distal to the MP joint and contributes to the lateral slip.
What is the function of the lumbrical tendon in digits 2-4?
Inserts onto the extensor wing and may merge with the medial slip of the interossei.
What anatomical features are labeled in the diagrams of the extensor expansion?
Medial Slip, Wing, Sling, Interosseous, and Lumbrical.
What is the debated aspect of the lumbrical tendon in relation to the sling?
Whether it inserts onto the deep surface of the sling.
What tendon inserts directly onto the proximal phalanx of the hallux?
EHB (Extensor Hallucis Brevis) tendon.
Which muscles contribute to the medial expansion of the hallux?
Abductor hallucis and medial head of flexor hallucis brevis.
Which muscles contribute to the lateral expansion of the hallux?
Adductor hallucis and lateral head of flexor hallucis brevis.
What does the lumbrical to digit 5 form?
Extensor wing medially.
Which muscle does not send a tendon to digit 5?
EDB (Extensor Digitorum Brevis).
Which muscles contribute to the lateral expansion of digit 5?
Abductor digiti minimi and flexor digiti minimi.
What muscles insert onto the wings of the extensor expansions for digits 2–5?
Lumbricals.
Which muscles are associated with the fifth digit in the extensor expansions?
Abductor digiti minimi and flexor digiti minimi.
What muscles are associated with the hallux in the extensor expansions?
Abductor hallucis, adductor hallucis, and flexor hallucis brevis.
What is the significance of the long extensors in relation to the extensor sling?
The pull of long extensors tightens the sling, causing hyperextension of the MP joint and passive flexion of the IP joints.
What is necessary to extend the IP joints according to the extensor expansions?
Contraction of muscles inserting onto the wings is necessary to extend IP joints.
What is the role of the extensor sling in the foot?
It facilitates the movement of the long extensor and helps in the extension of the toes.
What are the main nerves involved in the cutaneous innervation of the foot?
Lateral dorsal cutaneous, Superficial fibular, Saphenous, Deep fibular.
Which nerve is the only motor nerve in the dorsum of the foot?
Lateral branch of deep fibular nerve.
What areas are innervated by the Superficial fibular nerve?
It innervates the lateral and anterior aspects of the leg and the dorsum of the foot.
What is the role of the Saphenous nerve in cutaneous innervation?
It provides sensory innervation to the medial aspect of the foot.
Which nerve branches are associated with the deep fibular nerve?
Medial branch of deep fibular and 1st dorsal digital nerve.
What is the function of the Lateral dorsal cutaneous nerve?
It innervates the skin on the lateral side of the foot.
What does the term 'common dorsal digital nerves' refer to?
They refer to branches that innervate the toes on the dorsum of the foot.
What is the significance of the Intermediate dorsal cutaneous nerve?
It is a branch of the Superficial fibular nerve that innervates the skin between the toes.
What are the four main nerves involved in the cutaneous innervation of the foot?
Sural, Superficial Fibular, Deep Fibular, and Saphenous nerves.
What does the Sural nerve branch into and what area does it innervate?
It branches into the Lateral Dorsal Cutaneous nerve, which innervates the 10th Dorsal Digital area.
What are the two pathways of the Superficial Fibular nerve?
The Intermediate Dorsal Cutaneous nerve and the Medial Dorsal Cutaneous nerve.
What areas does the Intermediate Dorsal Cutaneous nerve innervate?
It branches into the 3rd Common Dorsal Digital nerve (innervating the 8th & 9th Dorsal Digital area) and the 2nd Common Dorsal Digital nerve (innervating the 6th & 7th Dorsal Digital area).
What does the Medial Dorsal Cutaneous nerve stem from and what does it innervate?
It stems from the Deep Fibular nerve and innervates the 1st Common Dorsal Digital nerve (innervating the 4th & 5th Dorsal Digital area) and the Medial Branch nerve (innervating the 2nd & 3rd Dorsal Digital area).
Which nerve directly innervates the 1st Dorsal Digital area?
The Saphenous nerve.
What is the central artery depicted in the arterial network of the foot?
Dorsalis Pedis
Which arteries branch off from the Dorsalis Pedis?
Lateral Tarsal and Medial Tarsal
What are the two arteries that branch below the Dorsalis Pedis?
Arcuate and Deep Plantar
What do the Arcuate and Deep Plantar arteries lead to?
2nd-4th Dorsal Metatarsal and 1st Dorsal Metatarsal
What arteries are connected to the 2nd-4th Dorsal Metatarsal?
10th Dorsal Digital, 4th-9th Dorsal Digital, 2nd & 3rd Dorsal Digital, and 1st Dorsal Digital
What is the function of the Perforating fibular artery?
It connects to the Dorsalis Pedis and contributes to the arterial supply of the foot.
What is the significance of the anterior and posterior perforating arteries?
They connect the dorsal metatarsal arteries to the plantar metatarsal arteries.
What are the key arteries highlighted in the illustration of the arteries of the foot?
Perforating fibular, lateral tarsal, arcuate, deep plantar artery, deep plantar arch, proximal perforating, plantar metatarsal, and distal perforating.
What is the relationship between the perforating fibular and lateral tarsal arteries?
They are anastomosed together.
What common variation occurs with the dorsalis pedis artery?
It comes from the perforating fibular artery.
What is a common variation regarding the arcuate artery?
It is often small or absent.
From where do the dorsal metatarsal arteries typically arise?
From perforating branches.
Where does the 1st dorsal metatarsal artery originate?
From the deep plantar artery.
What is a possible origin for the 10th dorsal digital artery?
It may come from the lateral plantar artery.
What is a possible origin for the 1st dorsal digital artery?
It may come from the medial plantar artery.
What is the medial dorsal digital vein of the 1st toe also known as?
1st dorsal digital vein
What is the lateral dorsal digital vein of the 5th toe also known as?
10th dorsal digital vein
What is a characteristic of superficial veins in the foot?
They are extremely variable.
What do deep veins split into that run with arteries?
Two or more venae comitantes.
What vein is associated with the small saphenous vein?
Lateral marginal vein.
What vein is associated with the great saphenous vein?
Medial marginal vein.
What is the function of the dorsal venous arch?
It collects blood from the dorsal metatarsal veins and drains into the saphenous veins.
How many dorsal metatarsal veins are there?
Four.
What is the relationship between deep veins and arteries in the foot?
Deep veins run alongside arteries as venae comitantes.
What is the function of the Lateral marginal vein?
It connects to the small saphenous vein.
What is the Dorsal venous arch?
A structure that collects blood from the dorsal metatarsal veins and connects to the marginal veins.
How many dorsal metatarsal veins are there?
There are four dorsal metatarsal veins.
What does the Medial marginal vein connect to?
It connects to the great saphenous vein.
What is the significance of the 10th dorsal digital vein?
It is part of the network of veins in the foot that drains into the dorsal venous arch.
What veins flow into the Dorsal venous arch?
The 1st-4th dorsal metatarsal veins and the dorsal digital veins.
What are the two main saphenous veins mentioned?
The small saphenous vein and the great saphenous vein.
What is the role of the dorsal digital veins?
They drain blood from the toes and connect to the dorsal metatarsal veins.
What are the most superficial structures in the foot anatomy during dissection?
Veins and cutaneous nerves.
Where do veins and cutaneous nerves run in the foot?
In the superficial fascia.
What should you be cautious of when working with veins and cutaneous nerves?
They are very easy to cut accidentally.
What does the deep fascia of the dorsum of the foot prevent?
Bowstringing of the tendons of the extrinsic muscles of the foot at the ankle.
What is the deep fascia of the dorsum of the foot continuous with?
The crural fascia of the leg.
What are retinacula?
Thickenings of deep fascia that hold tendons in place and prevent bowstringing at joints.
What is the superior extensor retinaculum?
A simple band of deep fascia running transversely between the distal tibia and fibula.
Where does the superior extensor retinaculum attach laterally?
To the anterior border of the distal fibula and lateral surface of the lateral malleolus.
What tendons pass deep to the superior extensor retinaculum?
The tendons of extensor digitorum longus, extensor hallucis longus, fibularis tertius, and tibialis anterior.
How is the deep fascia of the dorsum of the foot arranged?
It divides the dorsum of the foot into three layers from superficial to deep.
What does the first layer of the deep fascia contain?
The tendons and synovial sheaths of tibialis anterior, extensor hallucis longus, extensor digitorum longus, and fibularis tertius muscles.
What does the second layer of the deep fascia contain?
The extensor digitorum brevis muscle.
What does the third layer of the deep fascia contain?
The dorsalis pedis artery and its branches, the perforating branch of the fibular artery, accompanying veins, and the deep fibular nerve and its branches.
What is the shape of the inferior extensor retinaculum?
Usually 'Y'-shaped but may be 'X'-shaped with an oblique superolateral band.
What are the three roots of the frondiform ligament attached to?
Each root attaches to either the talus or calcaneus.
Where is the lateral root of the frondiform ligament attached?
To the tarsal sinus of the calcaneus, lateral to the origin of the extensor digitorum brevis.
What does the medial root of the frondiform ligament blend with?
It may blend with the interosseous talocalcaneal ligament.
What does the superomedial oblique band form?
The superior arm of the 'Y'.
What structures does the superficial portion of the superomedial oblique band pass over?
The tendon of the extensor hallucis longus muscle, anterior tibial artery and vein, and deep fibular nerve.
Where does the inferomedial oblique band attach?
Medially to the plantar aponeurosis, navicular tuberosity, and medial cuneiform.
What is the function of the extensor expansions?
They are formed by the tendons of the extensor digitorum longus and extensor hallucis longus muscles to extend the toes.
What are the components of the extensor expansions for digits 2-4?
One central slip and two lateral slips from the EDL tendons.
Where does the central slip of the extensor expansion insert?
On the base of the middle phalanx.
What is the terminal slip and where does it insert?
The terminal slip inserts on the base of the distal phalanx.
What do the tendons of the extensor digitorum brevis (EDB) join with?
They join the lateral aspect of the extensor digitorum longus (EDL) tendons at or distal to the division into three slips.
What is the proximal part of the extensor expansion known as?
The extensor sling (transverse lamina, quadrilateral lamina).
What does the extensor sling attach to?
It attaches to the plantar plate and deep transverse metatarsal ligament.
What is the triangular distal part of the extensor expansion called?
The extensor wing (extensor hood).
How does the extensor wing relate to the extensor sling?
The extensor wing is continuous proximally with the extensor sling.
Which tendons insert onto the medial extensor wing?
Lumbrical tendons insert onto the medial extensor wing, forming its inferior margin.
What contributes to the extensor expansion for digit 1?
Only the tendon of the extensor hallucis longus contributes to the formation of the extensor expansion for digit 1.
What muscles contribute to the extensor expansion for digit 5?
The abductor digiti minimi and flexor digiti minimi contribute to the extensor expansion laterally for digit 5.
What is the function of the extensor digitorum longus (EDL)?
The EDL pulls the proximal phalanx into extension (or hyperextension) at the metatarsophalangeal joint.
How does the extensor digitorum brevis (EDB) function?
Contraction of the EDB pulls on the lateral slip and terminal slips of the digits and acts to extend the interphalangeal joints.
What is the action of the lumbricals at the metatarsophalangeal joints?
The lumbricals act to flex the metatarsophalangeal joints, but also extend the interphalangeal joints through their attachment to the extensor expansions.
What is the role of the interossei in relation to the extensor expansions?
The action of the interossei on flexion/extension of the digits depends on their contribution to the extensor expansions; they are primarily flexors of the metatarsophalangeal joint.
What is the origin of the extensor digitorum brevis?
Dorsolateral surface of calcaneus anterior to tarsal sinus & interosseous talocalcaneal ligament.
Where does the extensor digitorum brevis insert?
Lateral surface of extensor digitorum longus tendons of 2nd, 3rd, & 4th digits distal to MPJ.
What is the innervation of the extensor digitorum brevis?
Lateral branch of deep fibular nerve; accessory fibular branch from superficial fibular nerve in 20% of individuals.
What is the function of the extensor digitorum brevis?
Extends phalanges & MPJ of 2nd-4th digits.
What variations can occur in the extensor digitorum brevis?
May partially originate from talus, navicular, lateral cuneiform, 3rd metatarsal, or cuboid; may have two tendons, a tendon to 5th digit, or doubled tendons.
What is the origin of the extensor hallucis brevis?
Same as extensor digitorum brevis; tendon crosses dorsalis pedis artery.
Where does the extensor hallucis brevis insert?
Dorsal surface of base of proximal phalanx of hallux.
What is the function of the extensor hallucis brevis?
Extends MPJ of hallux.
What does the superficial fibular nerve provide?
Cutaneous innervation to the dorsum of the foot.
What are the terminal branches of the superficial fibular nerve?
Medial and intermediate dorsal cutaneous nerves.
What does the medial dorsal cutaneous nerve give rise to?
The first dorsal digital nerve and first common dorsal digital nerve.
What does the first dorsal digital nerve innervate?
The medial side of the great toe.
Where does the first common dorsal digital nerve course?
To the space between the second and third toes, dividing into the fourth and fifth dorsal digital nerves.
What communication occurs with branches of the medial dorsal cutaneous nerve?
They communicate with the saphenous nerve and occasionally with the medial branch of the deep fibular nerve.
What does the intermediate dorsal cutaneous nerve divide into?
The second and third common dorsal digital nerves.
What areas do the second and third common dorsal digital nerves innervate?
The third and fourth intermetatarsal spaces, respectively.
What does each common dorsal digital branch divide into?
Two dorsal digital nerves within its webspace, the 6th-9th dorsal digital nerves.
What nerve does the intermediate dorsal cutaneous nerve communicate with?
The lateral dorsal cutaneous nerve.
What does the deep fibular nerve accompany into the dorsum of the foot?
The anterior tibial artery.
What are the terminal branches of the deep fibular nerve?
The medial and lateral branches.
What does the lateral branch of the deep fibular nerve provide motor innervation to?
The extensor digitorum brevis muscle.
What does the medial branch of the deep fibular nerve run with?
The dorsalis pedis artery.
What does the medial branch of the deep fibular nerve supply?
The skin of adjacent sides of the first and second toes.
What does the sural nerve become in the lateral dorsum of the foot?
The lateral dorsal cutaneous nerve.
What does the sural nerve supply after passing the fifth metatarsophalangeal joint?
The lateral side of the fifth digit as the tenth dorsal digital nerve.
What is the saphenous nerve a branch of?
The femoral nerve.
Where does the saphenous nerve provide cutaneous innervation?
To the medial arch of the foot.
What artery supplies the dorsum of the foot?
Branches of the anterior tibial artery.
Where does the anterior medial malleolar artery branch from?
The anterior tibial artery about 5 cm proximal to the ankle joint.
What does the anterior medial malleolar artery anastomose with?
Branches of the dorsalis pedis, posterior tibial, and medial plantar arteries.
What is the origin of the anterior lateral malleolar artery?
From the lateral aspect of the anterior tibial artery near the anterior medial malleolar branch.
What does the dorsalis pedis artery change its name from?
The anterior tibial artery at the transmalleolar line.
What is the typical diameter of the dorsalis pedis artery?
Usually about 2-3 mm, but may vary.
What happens if the dorsalis pedis artery is absent?
The plantar arteries or the perforating branch of the fibular artery takes over.
Where can the pulse of the dorsalis pedis artery be felt?
As it passes over the tarsal bones in between the tendons of the extensor hallucis longus and extensor digitorum longus.
What forms an anastomotic network along the dorsum of the foot?
Small branches arising from the dorsalis pedis, along with branches of the lateral tarsal and arcuate arteries.
What is the origin of the lateral tarsal artery?
Often the largest branch of the dorsalis pedis, diverging dorsal to the neck of the talus.
What does the lateral tarsal artery supply?
It supplies the extensor digitorum brevis muscle and anastomoses with the lateral plantar artery.
What is the anatomical relationship of the lateral tarsal artery to the fibularis brevis muscle?
It runs deep to the tendon of the fibularis brevis muscle.
How many medial tarsal arteries typically originate from the dorsalis pedis?
Usually two medial tarsal arteries.
What do the medial tarsal arteries supply?
They supply the medial aspect of the tarsal bones and contribute to the medial malleolar rete.
In what percentage of cases does the artery to the sinus tarsi originate from the lateral tarsal artery?
In 20-30% of cases.
Where does the arcuate artery typically originate?
From the dorsalis pedis artery at the level of the first tarsometatarsal joint.
What does the arcuate artery give rise to as it crosses the foot?
It gives rise to the second, third, and fourth dorsal metatarsal arteries.
How many dorsal metatarsal arteries are there?
There are four dorsal metatarsal arteries.
What is the function of the dorsal metatarsal arteries?
They run in intermetatarsal spaces and terminate at the metatarsophalangeal joint by dividing into two dorsal digital arteries.
What do the dorsal digital arteries supply?
They supply the adjacent sides of the second through fifth toes.
What is the pathway of the first dorsal metatarsal artery?
It runs distally in the first interosseous space and gives off the first dorsal digital artery.
What do the tributaries to the dorsalis pedis veins follow?
They follow the dorsalis pedis artery and its branches proximally to become the anterior tibial veins.
