Ankle And Foot

-*anteriorly lying head articulates with the navicular bone* -neck, and a body with a superior trochlear surface articulates with the tibia and fibula. -The *inferior surface has three sites for articulation with calcaneus*. -The *posterior process of the talus has a medial and lateral tubercle* that flank the groove for the tendon of the flexor hallucis longus muscle. -Sometimes the lateral tubercle ossifies separately from the rest of the talus and appears as a separate bone, the *os trigonum*, posterior to the talus

-forms the heel, *supports the talus above*. -The calcaneal tendon attaches middle portion of the posterior part of the calcaneus. -The calcaneal tuberosity lies inferior, extends to the plantar surface, having a medial and lateral process for muscle attachment. -*The sustentaculum tali* is a medial ridge of bone that helps to *support the head of the talus and is grooved by the tendon of the flexor hallucis longus*. -The tarsal sinus is a gap between the anterior surfaces of the talus and calcaneus that is filled with interosseous talocalcaneal ligament.

-*Hindfoot* - includes the talus and calcaneus -*Midfoot* - includes the navicular, cuboid and three cuneiform bones -*Forefoot* - includes the metatarsal and phalanges -*Plantar surface* - the sole of the foot -*Dorsal surface* - the part of the foot facing superiorly -*Heel* - the part of the sole inferior to the calcaneus -*Ball of foot* - the part of the sole inferior to the heads of the metatarsal bones -*Hallux* - the great toe or first digit; the most medial toe

-*fibrous joint formed between the medial surface of the distal fibula and the lateral surface of the distal tibia*. -connected by the very strong tibiofibular interosseous ligament. -It is stabilized further by the anterior, posterior, and transverse tibiofibular ligaments. -*Damage, most commonly the anterior tibiofibular ligament, is termed "high ankle sprain"*. -*stabilizes the superior articular surface* forming the ankle joint.

-Dorsiflexion and plantarflexion are the two main movements allowed at the ankle joint.

-called the "deltoid ligament" due to its triangular shape with apex of triangle at the attachment sites on medial malleolus and it fans out to attach to the talus, calcaneus, and navicular bones by anterior and posterior tibiotalar ligaments, the tibiocalcaneal ligament, and the tibionavicular ligament.

-*the anterior and posterior talofibular ligaments and the calcaneofibular ligament*. -*Sprains* commonly are due to *inversion stresses where the lateral ligaments are damaged* -*the anterior talofibular ligament Always Torn First*.

-synovial joint between the concave posterior calcaneal surface of the talus and the convex posterior talar articular surface on the calcaneus. -The joint is stabilized by the medial, lateral, and posterior talocalcaneal ligaments, as well as the interosseous talocalcaneal ligament that lies within the tarsal sinus.

-synovial joint, the head of the talus articulates with the navicular bone, the plantar calcaneonavicular (spring) ligament, and the sustentaculum tali and anterior talar articular surfaces of the calcaneous. -support and functioning is the plantar calcaneonavicular ligament - also called the "spring ligament" -also supported by the talonavicular ligament, the interosseous talocalcaneal ligament and the medial part of the bifurcate ligament.

-synovial joint between the anterior surface of the calcaneus and the posterior surface of the cuboid. -The *bifurcate ligament stabilizes* both the calcaneocuboid and talocalcaneonavicular joints. -body's weight is transmitted through the calcaneocuboid joint which is stabilized inferiorly by the long and short plantar ligaments. -The long plantar ligament attaches to the plantar surfaces of calcaneus and the cuboid -The short plantar ligament (plantar calcaneocuboid ligament) deep to the long plantar ligament and attaches to inferior surfaces of the anterior calcaneous and the cuboid.

-functional joint that spans across the foot, composed of *the talocalcaneonavicular and the calcaneocuboid joints*. -It is here that the hindfoot and midfoot rotate with respect to each other. -Movements at this joint along with the subtalar joint *produce the complex movements associated with inversion and eversion* of the foot.

*medial longitudinal arch* -the highest and most important arch. It consists of the calcaneus, talus, navicular bone, the three cuneiform bones, and the medial three metatarsal bones. *lateral longitudinal arch* - this is much flatter than the medial arch. It consists of the calcaneus, cuboid, and lateral two metatarsal bones. *Transverse arch* - occurs at the junction of the midfoot and forefoot and consists of the bases of the metatarsal bones, the cuboid, and the three cuneiform bones

-Flat foot -occurs when the medial longitudinal arch is depressed and the forefoot is displaced laterally and everted. -can be either flexible or rigid and can be either congenital or acquired. -There are numerous factors which could lead to an imbalance in the normal factors that support the medial longitudinal arch.

-Clawfoot -occurs when the medial longitudinal arch is more highly arched than normal. Various etiologies for this disease exist including muscular imbalances and bone defects

-a broad, thin muscle that forms the fleshy mass on the lateral aspect of the dorsum of the foot. -attachments - *proximally* to the superior and lateral surface of calcaneus and *distally* the three tendons merge with the tendons of the extensor expansions of toes two, three, and four. -*action* - assists in extending phalanges of digits 2, 3, and 4.

-*attachments* - may be considered the medial portion of the extensor digitorum brevis attaching to the calcaneus proximally and to the dorsal surface of the base of the first phalanx distally. -*action*- assists in extending the proximal phalanx of the great toe.

-the deep fibular nerve

-has medial dorsal and intermediate dorsal cutaneous branches which provide cutaneous sensation to the majority of the dorsum of the foot

-supplies cutaneous sensation to the lateral aspect of the dorsal surface of the first digit and the medial aspect of the second digit (in the web between the great toe and the second toe).

-supplies cutaneous sensation along the lateral margin of the foot and the lateral side of the fifth digit

-supplies cutaneous sensation along the medial side of the foot as far anteriorly as the head of the first metatarsal bone

-innervated by dorsal branches from the proper plantar digital nerves (from medial and lateral plantar nerves).

-The lateral aspect of dorsum of the foot is from S1 dermatome - L5 is dermatome for middle portion - either L5 or L4 for the medial aspect of foot dorsum

-The superficial fibular nerve can be entrapped as it exits the fascia in the distal anterolateral aspect of the leg. -The most common site of entrapment of the deep fibular nerve is *as this nerve passes deep to the inferior extensor retinaculum (called "anterior tarsal syndrome")*. -In both of these entrapment conditions, the primary *clinical sign can be "vague pain over the dorsum of the foot."* -The specific nerve affected can be identified either because the pain becomes more localized (between the first two toes or over the lateral aspect of the foot) or by diagnostic injection of local anesthetic at the site of nerve entrapment. -Entrapment of the deep fibular nerve can result in atrophy of the dorsal foot muscles.

-continuation of the anterior tibial artery at the level of the ankle joint, midway between the medial and lateral malleoli -passes deep to the inferior extensor retinaculum and courses distally against the dorsum of the bones towards the interspace between the first and second toes

-arises from the dorsalis pedis artery and courses laterally, deep to the extensor digitorum brevis muscle which it supplies. It anastomoses with the arcuate artery.

-arises *from the dorsalis pedis artery at the level of the bases of the metatarsal bones*. -This artery courses laterally, deep to the extensor tendons and *gives rise to three dorsal metatarsal arteries before anastomosing with the lateral tarsal artery*. -Each dorsal metatarsal artery gives off perforating branches to the sole of the foot before passing to the cleft of the toes and dividing into two dorsal digital arteries to supply the sides of the toes on either side of the cleft.

-arises directly *from the termination of the dorsalis pedis artery* and splits to form the dorsal digital arteries that -*supply the first digit and the medial side of digit two*.

-is the largest *branch of the dorsalis pedis artery*. -It courses *between the two heads of the first dorsal interosseous muscle* to *enter the sole* of the foot where it *anastomoses with the lateral plantar artery* to complete the plantar arterial arch

-This layer is *thick and fibrous*, with *retinacular cutis (skin ligaments) connecting the skin to the deeper plantar aponeurosis*. -Between these fibrous septa are fat- filled areas aiding in shock absorption

-consists of a *thin medial plantar fascia* over the intrinsic muscles of the hallux, a thicker *lateral plantar fascia* over the heel and fifth toe area, and a very thick central dense fibrous connective tissue structure, *the plantar aponeurosis*

-*attaches* posteriorly to the medial process of the *calcaneal tuberosity* and divides into digital slips towards the ball of the foot. -Transverse fibers, the superficial transverse metatarsal ligament, interconnect the digital slips near the heads of the metatarsal bones. -The plantar aponeurosis *serves to* protect the deeper components of the sole from injury, to support the longitudinal arches of the foot, and to bind the parts of the foot together

-*medial compartment*: the abductor hallucis flexor hallucis brevis the tendon of the flexor hallucis longs muscle -*lateral compartment*: the abductor digiti minimi flexor digiti minimi brevis muscles -*central compartment*: the flexor digitorum brevis the quadrates plantae the adductor hallucis the four lumbrical muscles the tendons of the flexor digitorum longs muscle -*interosseous compartment* dorsal and plantar interosseous muscles

-inflammation and pain near the attachment site of the plantar fascia to the medial process of the calcaneal tuberosity. -Non-surgical treatments usually are attempted for many months before approaching these cases surgically

-*1st Layer*: abductor hallucis flexor digitorum brevis abductor digiti minimi -*2nd Layer* quadratus plantae (flexor accessorius) lumbricals -*3rd Layer* flexor hallucis brevis adductor hallucis flexor digiti minimi brevis -*4th Layer* plantar interossei dorsal interossei

-*attaches to* the medial process of the tuber calcaneus and the flexor retinaculum -*inserts into* the medial side of the base of the proximal phalanx of the hallux. -*It abducts and flexes the hallux*

-*attaches to* the medial process of the tuber calcaneus. It gives rise to four tendons which initially lie superficial to the four tendons of the flexor digitorum longus. The tendons of the flexor digitorum brevis then split and allow the longus tendons to pass through this slit to *attach to the distal phalanges*. -The brevis tendons insert on the middle phalanges of the lateral four digits. -This muscle assists in *flexing the lateral four digits*

-*attaches to* the calcaneus -*inserts into* the lateral aspect of the proximal phalanx of the fifth digit. -*It abducts and flexes this digit*

-*arises by* two heads from the plantar surface of the calcaneus. -These *two heads converge and insert into* the lateral margin and the superficial and deep surfaces of the tendon of the flexor digitorum longus muscle. -The quadratus plantae *assists in flexion of the four lateral toes* by straightening the line of pull of the obliquely oriented tendons of the flexor digitorum longus

-*arise from* the tendons of the flexor digitorum longus and *terminate on* the medial aspect of the extensor expansion of the four lateral toes. -The main action of these muscles is to *extend the interphalangeal joints of the toes* so that the toes do not fold under because of the strong action of the flexor digitorum longus (but they also flex metatarsophalangeal joints.)

-is a two-bellied muscle with the *lateral head arising from the cuboid and lateral cuneiform bones* while the *medial head arises from* the tendon of the tibialis posterior muscle. -The *medial portion inserts into* the medial sesamoid bone of the hallux and the medial side of the base of the proximal phalanx along with the abductor hallucis. *The lateral portion inserts into* the lateral sesamoid bone and the lateral side of the base of the proximal phalanx along with the adductor hallucis. -This muscle *flexes the proximal phalanx of the first digit*

-has both an oblique and a transverse head. -*The oblique head arises from* the bases of the 2nd, 3rd, and 4th metatarsal bones -*the transverse head arises from* the deep ligaments associated with the 3rd, 4th, and 5th toes. -*The two heads join and insert into* the lateral sesamoid bone and the lateral side of the base of the proximal phalanx of the hallux along with the lateral head of the flexor hallucis brevis. -This muscle *adducts the hallux and helps to support the transverse arch* of the foot

-*arises from* the base of the 5th metatarsal bone -inserts into the lateral side of the base of the proximal phalanx of the 5th digit. -It flexes the proximal phalanx of this digit

-*arise from* the medial surface of a metatarsal bone (either 3rd,4th, or 5th digit) -*inserts into* the medial side of the base of the proximal phalanx of the same digit. -These muscles theoretically can *adduct the digit* with which they are associated. (Remember: The plane of reference for adduction/abduction in the foot is through the second toe.)

-are bipennate and *arise from* the sides of the two metatarsals between which they arise. -The first and second dorsal interosseous muscles insert into the medial (1st) and lateral (2nd) sides of the base of the proximal phalanx of the 2nd digit. The third dorsal interosseous muscle inserts into the lateral side of the proximal phalanx of the 3rd digit while the fourth dorsal interosseous muscle inserts in the same position on the 4th digit. -These muscles theoretically can *abduct the digits*.

-*arises from the tibial nerve* deep to the flexor retinaculum -*runs anteriorly between* the abductor hallucis and flexor digitorum brevis muscles. The medial plantar nerve becomes more superficial near the bases of the metatarsal bones and divides into the proper digital branches for the medial three and a half digits. -*supplies motor innervation to* the abductor hallucis, flexor digitorum brevis, flexor hallucis brevis, and the most medial lumbrical muscle. -*It provides sensory supply to* the medial aspect of the sole extending to the medial three and a half toes including branches to the nail on the dorsal surface

-arises deep to the flexor retinaculum as the *smaller of the two terminal branches of the tibial nerve* -runs medial to the lateral plantar artery as it passes diagonally between the flexor digitorum brevis and quadratus plantae muscles. *At the lateral aspect* of the quadratus plantae, near the base of the 5th metatarsal bone, it *divides into a superficial and deep branch*. -*The deep branch* heads deeply, around the margin of this muscle, to run medially with the plantar arterial arch across the proximal ends of the interosseus muscles and deep to the oblique head of the adductor hallucis. -*The superficial branch* emerges between the flexor digitorum brevis and abductor digiti minimi muscles to provide both motor and sensory branches to lateral structures -*provides motor innervation to* the quadratus plantae, abductor digiti minimi, flexor digiti minimi brevis, adductor hallucis, all the interossei muscles, and 2nd, 3rd, and 4th lumbrical muscles. -*It supplies cutaneous innervation* for the lateral aspect of the sole including the lateral part of the 4th digit and all of the 5th digit

-runs anteriorly below the lateral malleolus and passes along the lateral side of the foot and 5th digit

-These branches pass through the flexor retinaculum and innervate the skin of the heel and medial side of the sole of the foot

-arises from the femoral nerve -passes *through the adductor canal* and *exists at the medial aspect of the knee*. It descends on the medial aspect of the leg *accompanying the great saphenous vein anterior to the medial malleolus* -supplies the skin on the medial foot as far anteriorly as the ball of the great toe.

-generally are shown as representing L4, L5, and S1 (sometimes some S2) innervation patterns

-arises from the posterior tibial artery deep to the flexor retinaculum and abductor hallucis muscle -courses with the medial plantar nerve, at first under the abductor hallucis muscle and then between it and the flexor digitorum brevis muscle

-the *larger of the two terminal branches of the posterior tibial artery* -lies lateral to the lateral plantar nerve as it passes diagonally in the foot between the first and second muscle layers. The lateral plantar artery sends branches along with the superficial branch of the lateral plantar nerve, as well as having a branch that curves around deeply with the deeper branch of the nerve, *to contribute to the plantar arterial arch*

-*formed by the deep portion of the lateral plantar artery* and by the deep plantar artery, as it enters the sole by passing between the first two metatarsal bones. -lies deep to the adductor hallucis, on the plantar surface of the bases of the 2nd, 3rd, and 4th metatarsal bones

-Venous blood travels from the medial side of this arch into the great saphenous vein and from the lateral side of this arch into the small saphenous vein

-formed by plantar metatarsal veins. It accompanies the plantar arterial arch between the third and fourth layers of the sole of the foot

-These lymphatic vessels accompany the great saphenous vein and drain into the vertical group of superficial inguinal lymph nodes near the saphenous hiatus.

-These lymphatics accompany the small saphenous vein and drain into the popliteal lymph nodes, posterior to the knee

-accompany the deeper veins of the foot and then ascend with the anterior and posterior tibial veins to empty into the popliteal lymph nodes