Bones of the Foot - Tarsals - Metatarsals - Phalanges - TeachMeAnatomy The human foot is a very complex and highly developed structure. The bones of the foot provide mechanical support for the soft tissues, helping the foot withstand the weight of the body. The bones of the foot can be divided into three categories: Tarsals – A set of seven irregularly shaped bones. They are situated proximally in the foot, in the ankle area. Metatarsals – These bones connect the phalanges to the tarsals. There are five in number – one for each digit. Phalanges – The bones of the toes. Each toe has three phalanges – a proximal, intermediate and distal (except the big toe, which only has two phalanges). Fig 1.0 – Overview of the bones of the human foot. Tarsals The tarsal bones of the foot are organised into three rows; proximal, intermediate and distal. Proximal Group The proximal tarsal bones are the talus and the calcaneus. They form the bony framework around the proximal ankle and heel area. The talus is the most superior of the tarsal bones.

It has three articulations: Superiorly: Ankle joint – between the talus and the bones of the leg (the tibia and fibula). Inferiorly: Subtalar joint – between the talus and calcaneus. Anteriorly: Talonavicular joint – between the talus and the navicular. The main function of the talus is to transmit forces from the tibia to the heel bone (known as the calcaneus). Whilst numerous ligaments attach to the talus, it is not a site of muscle attachment or origin. Fig 1.1 – The tarsal bones of the foot. The calcaneus lies underneath the talus, and has two articulations: Superiorly: Subtalar joint – between the calcaneus and the talus. Anteriorly: Calcaneocuboid joint – between the calcaneus and the cuboid. It is thick and sturdy, acting to transmit forces from the talus to the ground. The posterior aspect of the calcaneus is marked by calcaneal tuberosity, to which the Achilles tendon attaches.

Intermediate Group The intermediate row of tarsal bones contains one bone, the navicular (given its name because it is shaped like a boat). It articulates with the talus posteriorly, the cuneiform bones anteriorly, and the cuboid bone laterally. On the plantar surface of the navicular, there is a tuberosity for the attachment of the tibialis posterior tendon. Distal Group In the distal row, there are four tarsal bones – the cuboid and the three cuneiforms. These bones articulate with the metatarsals of the foot. The cuboid is the most lateral bone in the distal row, articulating with the calcaneus posteriorly, and two metatarsals anteriorly. As the name suggests, it is shaped like a cube. The inferior surface of the cuboid is marked by a groove for the fibularis longus muscle. The three cuneiforms (lateral, intermediate and medial) are wedge shaped bones. They articulate with the navicular posteriorly, and the metatarsals anteriorly. The shape of the bones helps form a transverse arch across the foot.

Clinical Relevance: Fractures of the Talus and Calcaneus The talus and the calcaneus sit in the proximal part of the foot and ankle, and are involved in transmitting forces from the body to the ground. They are the most frequently fractured of all the tarsal bones. Talus Talar fractures occur in two places – the neck of the talus, or the body: Neck fractures are caused by excessive dorsiflexion of the foot. The neck of the talus is pushed against the tibia. In this type of fracture, the blood supply to the talus may be disturbed, leading to avascular necrosis of the bone. Body fractures usually occur from jumping from a height. In any fracture of the talus, the malleoli of the leg bones act to hold the fragments together, so there is little displacement of the fracture pieces. By Jojo (Own work) [CC-BY-SA-3.0], via Wikimedia Commons Fig 1.2 – X-ray of a calcaneal fracture. Calcaneus The calcaneus is often fractured in a ‘crush‘ type injury.

The most common mechanism of damage is falling onto the heel from a height – the talus is driven into the calcaneus. The bone can break into several pieces – known as a comminuted fracture. Upon x-ray, the calcaneus will appear shorter and wider. Even after treatment, a calcaneal fracture can cause further problems. The sub-talar joint is usually disrupted, causing the joint to become arthritic. The patient will experience pain upon inversion and eversion – which can make walking on uneven ground particularly painful. Metatarsals The metatarsals are located in the midfoot, between the tarsals and phalanges. They are numbered I-V (medial to lateral). Each metatarsal has a similar structure. They consist of a distal head and proximal base, which are joined by a shaft of bone. They have three or four articulations: Proximally: Tarsometatarsal joint – between the metatarsal bases and the cuneiforms or cuboid bones. Laterally: Intermetatarsal joint(s) – between the metatarsal and the adjacent metatarsals.

Distally: Metatarsophalangeal joint – between the metatarsal head and the proximal phalanx. Clinical Relevance: Fractures of the Metatarsal Bones Metatarsal fractures can occur by three mechanisms. The most common method of fracture is a direct blow to the foot – usually from a heavy object dropping onto the foot. Another type of metatarsal injury is a stress fracture, an incomplete fracture caused by repeated stress to the bone. It is common in athletes, and occurs most frequently to metatarsals II, III and IV. The metatarsals can also be fractured by excessive inversion of the foot. If the foot is violently inverted, the fibularis brevis muscle can avulse (‘tear off’) the base of metatarsal V. Phalanges The phalanges are the bones of the toes. Most toes have three phalanges – proximal, intermediate and distal. The great toe only has proximal and distal phalanges. Each phalanx consists of a body, a proximal extremity and a distal extremity.

Anatomy Tables - Anterior & Lateral Leg & Foot Anatomy Tables - Anterior & Lateral Leg & Foot Osteology the bones of the ankle there are seven tarsal bones: talus, calcaneus, navicular, medial cuneiform, intermediate cuneiform, lateral cuneiform, cuboid ( N523 , TG3-61 ) formed by the combined talonavicular part of the talocalcaneonavicular and calcaneocuboid joints synovial joint responsible for inversion/eversion of the foot; transection across this joint is a standard method for surgical amputation of the foot talus the most proximal of the tarsal bones the talus articulates with the medial malleolus of the tibia and the lateral malleolus of the fibula to form the ankle mortise joint (Latin, talus = ankle bone) body the proximal part of the talus its superior (trochlear) part participates in the ankle joint and its inferior part articulates with the calcaneus occurs where the talus rests on and articulates with the calcaneus trochlea the superior portion of the body of the talus that lies between the two malleoli it

 has a smooth articular surface; it participates in the formation of the ankle joint (Latin, trochlea = pulley) the portion of the talus that projects anteriorly it articulates with the navicular bone the constricted part of the talus located proximal to the head the tarsal bone which forms the heel it is the largest and strongest bone in the foot; a fracture of the calcaneus which separates the tuberosity from the body can be a debilitating injury (Latin, calcis = heel) calcaneal tuberosity the inferior roughened area of the calcaneus which contacts the ground during weight-bearing it is the attachment site of the plantar aponeurosis, abductor digiti minimi, flexor digitorum brevis, and the long plantar ligament sustentaculum tali the shelf-like medial projection of bone located inferior to the medial malleolus it is a shelf of bone that articulates with and supports the talus; it is grooved inferiorly by the tendon of the flexor hallucis longus m.

(Latin, sustento = to hold upright) navicular the tarsal bone located distal to the talus and proximal to the three cuneiform bones it articulates with the head of the talus and all three cuneiform bones; it is the attachment site for an important ligament (plantar calcaneonavicular or "spring" ligament) that supports the medial longitudinal arch of the foot (Latin, navicular = small boat shaped structure) cuneiform, medial the most medial bone in the distal row of tarsal bones the cuneiform bones articulate with the navicular bone proximally and the bases of the metatarsal bones distally cuneiform, middle the intermediate bone of the three cuneiform bones the cuneiform bones articulate with the navicular bone proximally and the bases of the metatarsal bones distally cuneiform, lateral the bone that is located between the middle cuneiform and the cuboid bone the cuneiform bones articulate with the navicular bone proximally and the bases of the metatarsal bones distally cuboid the most lateral bone in the distal row of tarsal bones the cuboid bone articulates with the calcaneus proxim

ally and the fourth and fifth metatarsal bones distally metatarsals the bones located between the tarsal bones and the phalanges there are five metatarsal bones in the foot the proximal end of the metatarsal it articulates with the distal row of tarsal bones the slender shaft of the metatarsal it is also known as the diaphysis the rounded distal end of the metatarsal it articulates with the proximal phalanx of the corresponding digit phalanx (phalanges) the distal two or three bones in the digits of the foot there are a total of 14 phalanges in the foot; the great toe has two phalanges (proximal and distal) and each of the other four toes has three phalanges (proximal, middle and distal); (Latin, phalanx = line of soldiers) base the proximal end of the phalanx the base of the proximal phalanx articulates with the head of the corresponding metatarsal bone; the base of the middle or distal phalanx articulates with the head of the next most proximal phalanx the slender shaft of the phalanx also known as the diaph

ysis; the body of the distal phalanx is very short head the distal end of the phalanx the proximal, middle and distal phalanges each have a head; the head of a proximal or middle phalanx articulates with the base of the next most distal phalanx Muscles four muscles, from shafts of adjacent metatarsal bones bases of proximal phalanges for digit 2 (both sides) & digits 3,4 (lateral side) abduct digits 2-4 (move these digits away from midline as defined by a line passing through 2nd digit), flex metatarsophalangeal joints and extend interphalangeal joints of those digits deep branch of lateral plantar nerve remember DAB (dorsal interossei ABduct) and PAD (plantar interossei ADduct), then logic can tell you where these muscles insert (Latin, inter = between + os = bone) plantar interosseous, in foot base and medial side of metatarsals 3-5 bases of proximal phalanges and extensor expansions of digits 3-5 adduct digits 3-5 (move these digits toward the midline of

 the foot as defined by the second digit),flex metatarsophalangeal and extend interphalangeal joints of digits 3-5 deep branch of lateral plantar nerve remember PAD (plantar interossei ADduct) and DAB (dorsal interossei ABduct), and logic will tell you where these muscles must insert (Latin, inter = between + os = bone) Nerves sciatic lateral sural cutaneous, superficial and deep fibular nn.

superficial fibular br.: muscles of lateral compartment of leg (fibularis longus and brevis mm.); deep fibular br.: mm. of anterior compartment of leg (tibialis anterior, extensor hallucis longus, extensor digitorum longus, fibularis tertius); mm.

of dorsum of foot (extensor digitorum brevis and extensor hallucis brevis) superficial fibular: distal 1/3 of anterior leg; dorsum of foot excluding web between great toe and 2nd toe and distal interphalangeal segments of all toes; deep fibular: skin of the web between great and 2nd toes peroneal is old terminology which has been replaced by fibular fibular, superficial ( N519 , TG3-37 ) tibia, fibula, interosseous membrane, anterior intermuscular septum contains tibialis anterior, extensor hallucis longus, extensor digitorum longus, fibularis tertius; also anterior tibial artery, deep fibular nerve extensor retinaculum, superior ( N530 , TG3-45 ) strong band of deep fascia passing from the fibula to the tibia, proximal to the malleoli binds down the tendons of the muscles in the anterior compartment, preventing bowstringing during dorsiflexion of the ankle (Latin, retinaculum = a band or halter) extensor retinaculum, inferior ( N53

0 , TG3-45 ) a Y-shaped band of fascia attached laterally to the anterosuperior surface of the calcaneus forms a strong loop around the tendons of the fibularis tertius and extensor digitorum longus muscles (Latin, retinaculum = a band or halter) fibular retinaculum, superior a band of deep fascia that extends from the tip of the lateral malleolus to the calcaneus binds down the tendons of the fibularis longus and brevis (Latin, retinaculum = a band or halter) lateral compartment (evertor), leg anterior & posterior intermuscular septa, fibula contains: fibularis longus & brevis mm.; superficial fibular nerve calcaneometatarsal ligament deep fascia forming an investment of the plantar surface of the lateral compartment of the foot continuous with the plantar aponeurosis plantar aponeurosis deep fascia forming an investment of the plantar surface of the central and medial compartments of the foot continuous with the calcaneometatarsal ligament medial compartment, foot ( N533 , TG3-49 ) compartment of the great toe contains:

 abductor hallucis and flexor hallucis brevis mm., tendon of flexor hallucis longus m., medial plantar a., v., & n.

lateral compartment, foot compartment of the little (5th) toe contains: abductor digiti minimi and flexor digiti minimi brevis mm., branches of lateral plantar a., v., & n. central compartment, foot ( N533 , TG3-49 ) associated with the lateral 4 toes contains: flexor digitorum brevis & quadratus plantae mm. & lumbrical mm., tendons of flexor digitorum longus m., branches of lateral plantar a., v., & n. adductor-interosseous compartment, foot deepest of the foot compartments contains: adductor hallucis & plantar & dorsal interossei mm., deep branch of lateral plantar n. & plantar arterial arch medial longitudinal arch, foot formed by talus, navicular, cuneiforms, medial 3 metatarsals supported by spring ligament (plantar calcaneonavicular), assisted by tibialis anterior m. lateral longitudinal arch, foot formed by calcaneus, cuboid, lat. 2 metatarsals supported by long & short plantar ligaments, assisted by fibularis longus m.

transverse arch, foot supported by long & short plantar ligaments, assisted by fibularis longus & tibialis anterior & posterior mm. tarsal sinus space between the neck of the talus and the calcaneus contains the interosseous talocalcaneal ligament Clinical Terms Definition compartment syndrome a group of symptoms which indicate a nerve, blood vessel or tendon is being constricted due to swelling within a closed anatomic space. A compartment syndrome may occur in an extremity after trauma (fracture) or inflammation (carpal tunnel syndrome). Some medications can also precipitate this condition. Symptoms include numbness, tingling, pain or loss of movement in an extremity. Surgery may be indicated if symptoms are severe or prolonged. foot drop the most commonly injured nerve in the lower limb is the common fibular nerve, which wraps around the fibular neck. Severence of this nerve causes paralysis of all the muscles of the anterior and lateral compartments (dorsiflexors of the ankle and evertors of the foot). The loss of eversion of the foot and dorsiflexion of the ankle causes foot-drop.

shin splints an inflammatory condition of the anterior portion of the tibia that results from overuse (for example running on hard surfaces). Occurs in either trained athletes who don't stretch or individuals who lead a sedentary lifestyle and then start running. The cause is swelling of the muscles in the anterior compartment, then edema and muscle-tendon inflammation which reduces bloodflow to the muscles. Shin splints are a mild form of anterior compartment syndrome. bunion/hallux valgus a swelling or deformity at the head of the first metatarsal of the great toe (big toe) (Latin, hallux = great toe) flat foot a condition in which one or more of the arches of the foot have flattened out so that the entire sole of the foot rests upon the ground; also, the deformity, usually congenital, exhibited by such a foot; also known as splayfoot. talipes equinovarus (club foot) the most common congenital abnormality of the foot. Clubfoot may occur in several forms, but talipes equinovarus is the most common. In this case the foot turns downward and inward.

Treatment involves the extended use of orthopaedic splints or casts to correct the position of the foot, often combined with surgery. (Latin, talus = ankle + pes = foot) The material presented in these tables is contained in the book: MedCharts Anatomy by Thomas R. Gest & Jaye Schlesinger Published by ILOC, Inc., New York Copyright © 1995, unauthorized use prohibited. The excellent editorial assistance of Duke Anatomy Tables - Labs 14-16: Lower Limb ( N486 , TG3-04A , TG3-04B , TG3-05A , TG3-05B ) the two coxal bones and sacrum form the pelvis paired; the os coxae forms the lateral part of the pelvis; it is formed by three fused bones: ischium, ilium & pubis; also known as the innominate bone obturator foramen a large foramen formed by the pubic and ischial rami obturator means to occlude or stop up, a reference to the fact that the obturator membrane closes the obturator foramen almost completely; a site of attachment for the obturator externus m.

and obturator internus m. obturator groove groove on the inferior surface of the superior pubic ramus marks the area of passage of the obturator vessels and n. in the obturator canal ilium fan-shaped bone that forms the lateral prominence of the pelvis one of three bones that form the os coxae: ilium, ischium, pubis arcuate line ridge running from anteroinferior to posterosuperior on the inner surface of the ilium inferior boundary of the iliac fossa; marks the plane of transition from abdominal cavity to pelvic cavity; part of the iliopectineal line (Latin, arcuate = bowed) anterior inferior iliac spine inferior to anterior superior iliac spine attachment site of straight head of rectus femoris m.

anterior superior iliac spine spine at the anterior end of the iliac crest lateral attachment of the inguinal ligament greater sciatic notch ( N486 , TG6-04 ) the notch on the inferior portion of ilium located posteromedial to the ischial spine the greater sciatic notch is converted to the greater sciatic foramen by the sacrospinous ligament and the sacrotuberous ligament iliac crest arching superior margin of the ilium that forms the rim of the "fan" attachment for abdominal wall muscles iliac tubercle roughened area along the outer edge of the iliac crest posterior superior iliac spine spine at the posterior end of the iliac crest position marked by a dimpling of the skin ischium the "V"-shaped bone that forms the posteroinferior part of the pelvis one of the three bones that form the os coxae: ilium, ischium, pubis ischial spine ( N486 , TG6-04 ) the spine that arises just superior to the lesser sciatic notch it is the site of attachment of the sacrospinous ligament and the site of origin of the superior gemellus m.

(Greek, ischion = hip joint) ischial tuberosity ( N486 , TG6-04 ) the roughened projection that protrudes posteroinferiorly from the body of the ischium it is the site of attachment of the sacrotuberous ligament; it is the site of origin of the inferior gemellus m., quadratus femoris m. and the hamstring mm.

(semitendinosus, semimembranosus, long head of biceps femoris, ischiocondylar portion of the adductor magnus) (Greek, ischion = hip joint) lesser sciatic notch the notch located between the ischial tuberosity and the ischial spine the lesser sciatic notch is converted to the lesser sciatic foramen by the sacrospinous and sacrotuberous ligaments an angulated bone that forms the anterior part of the pelvis one of three bones that form the os coxae: ilium, ischium, pubis; its body forms 1/5 of the acetabulum; its symphyseal surface unites with the pubis of the opposite side to form the pubic symphysis; the superior and inferior pubic rami participate in the formation of the obturator foramen body superolateral portion of the pubis the body of the pubis forms about 1/5 of the acetabulum inferior ramus inferior "limb" that passes inferolaterally from the pubic symphysis articulates with the ischial ramus to form the ischiopubic ramus; attachment site for the root of the penis/cl

itoris (Latin, ramus = a branch) pecten ridge on superior surface of the superior pubic ramus attachment point of the pectineal ligament pubic crest ridge on the superior border of the superior ramus attachment of rectus abdominis & pyramidalis mm.

pubic tubercle process at the lateral end of pubic crest attachment point of the medial end of the inguinal ligament the head of the femur articulates with the acetabulum of the pelvis neck the constricted area distal to the head of the femur most of the blood supply to the head of the femur courses along the surface of the neck; fractures of the neck of the femur may result in avascular necrosis of the head greater trochanter a large process that projects superiorly from the junction of the neck and shaft of the femur the greater trochanter is the insertion site of the gluteus medius m., gluteus minimus m., piriformis m. and obturator internus m. (Greek, trochanter = a runner or roller, from trochos, a wheel. Originally used for the head of the femur, which turns like a wheel in its socket. Eventually it came to mean the bony processes of the femur) lesser trochanter a large process that projects from the posteromedial surface of the femur just distal to neck it is the insertion site of the common tendon of the psoas major and iliacus mm.

(iliopsoas m.) (Greek, trochanter = a runner or roller, from trochos, a wheel. Originally used for the head of the femur, which turns like a wheel in its socket. Eventually it came to mean the bony processes of the femur) trochanteric fossa a depression on the medial side of the greater trochanter on its posterior surface where the greater trochanter joins the neck it is the insertion site of the obturator externus m. intertrochanteric crest a heavy ridge on the posterior surface of the femur that connects the greater and lesser trochanters the quadratus femoris m. inserts on the intertrochanteric crest gluteal tuberosity a roughened area located on the posterior surface of the femur at the superior end of the lateral lip of the linea aspera it is one of the insertion sites of the gluteus maximus m. adductor tubercle a process that projects superior to the medial epicondyle of the femur it is the insertion site of the ischiocondylar part of the adductor magnus m.

linea aspera ( Practical1 , Practical2 ) a vertical ridge on posterior surface of the femur it is the insertion site of the medial (adductor) group of thigh muscles and the origin of the vastus intermedius m. and the short head of the biceps femoris m. (Latin, linea aspera = rough line, the linea aspera is a roughed longitudinal line on the posterior surface of the shaft of the femur which gives attachment to several muscles) pectineal line a prominent intermediate ridge extending from the central part of the linea aspera to the base of the lesser trochanter lateral epicondyle the enlargement of bone on the lateral side of the femur just superior to the lateral condyle it is the attachment site of the fibular collateral ligament and the site of origin of the popliteus m.

(Greek, kondylos = the knob formed by the knuckle of any joint) medial epicondyle the enlargement of bone on the medial side of the femur just superior to the medial condyle it is the attachment site of the tibial collateral ligament of the knee joint (Greek, kondylos = the knob formed by the knuckle of any joint) a ridge of bone that descends obliquely from lateral to medial on the posterior surface of the tibia it is the site of origin of the soleus m.

lateral condyle the heavy prominence on the lateral side of the proximal end of the tibia the lateral condyle articulates with the lateral condyle of the femur and with the head of the fibula (Greek, kondylos = the knob formed by the knuckle of any joint) medial condyle the heavy prominence on the medial side of the proximal end of the tibia the medial condyle articulates with the medial condyle of the femur; it is larger than the lateral condyle of the tibia (Greek, kondylos = the knob formed by the knuckle of any joint) medial malleolus the large bony prominence on the medial side of the ankle the medial malleolus of the tibia forms the medial side of the ankle joint; it articulates with the medial surface of the talus (Latin, malleus = hammer) tibial tuberosity the roughened protuberance on the anterior surface of the tibia located just distal to the condyles it is the attachment site of the patellar ligament, which represents the insertion of the quadriceps femoris tendon the bones of the ankle there are seven tarsal bones: talus, calcaneus, navicular,

 medial cuneiform, intermediate cuneiform, lateral cuneiform, cuboid ( N523 , TG3-61 ) formed by the combined talonavicular part of the talocalcaneonavicular and calcaneocuboid joints synovial joint responsible for inversion/eversion of the foot; transection across this joint is a standard method for surgical amputation of the foot talus the most proximal of the tarsal bones the talus articulates with the medial malleolus of the tibia and the lateral malleolus of the fibula to form the ankle mortise joint (Latin, talus = ankle bone) body the proximal part of the talus its superior (trochlear) part participates in the ankle joint and its inferior part articulates with the calcaneus the tarsal bone which forms the heel it is the largest and strongest bone in the foot; a fracture of the calcaneus which separates the tuberosity from the body can be a debilitating injury (Latin, calcis = heel) calcaneal tuberosity the inferior roughened area of the calcaneus which contacts the ground during weight-bearing it is the attachment site of the plantar aponeurosis

, abductor digiti minimi, flexor digitorum brevis, and the long plantar ligament sustentaculum tali the shelf-like medial projection of bone located inferior to the medial malleolus it is a shelf of bone that articulates with and supports the talus; it is grooved inferiorly by the tendon of the flexor hallucis longus m.

(Latin, sustento = to hold upright) navicular the tarsal bone located distal to the talus and proximal to the three cuneiform bones it articulates with the head of the talus and all three cuneiform bones; it is the attachment site for an important ligament (plantar calcaneonavicular or "spring" ligament) that supports the medial longitudinal arch of the foot (Latin, navicular = small boat shaped structure) cuneiform, medial the most medial bone in the distal row of tarsal bones the cuneiform bones articulate with the navicular bone proximally and the bases of the metatarsal bones distally cuneiform, middle the intermediate bone of the three cuneiform bones the cuneiform bones articulate with the navicular bone proximally and the bases of the metatarsal bones distally cuneiform, lateral the bone that is located between the middle cuneiform and the cuboid bone the cuneiform bones articulate with the navicular bone proximally and the bases of the metatarsal bones distally cuboid the most lateral bone in the distal row of tarsal bones the cuboid bone articulates with the calcaneus proxim

ally and the fourth and fifth metatarsal bones distally metatarsals the bones located between the tarsal bones and the phalanges there are five metatarsal bones in the foot the proximal end of the metatarsal it articulates with the distal row of tarsal bones the slender shaft of the metatarsal it is also known as the diaphysis the rounded distal end of the metatarsal it articulates with the proximal phalanx of the corresponding digit phalanx (phalanges) the distal two or three bones in the digits of the foot there are a total of 14 phalanges in the foot; the great toe has two phalanges (proximal and distal) and each of the other four toes has three phalanges (proximal, middle and distal); (Latin, phalanx = line of soldiers) base the proximal end of the phalanx the base of the proximal phalanx articulates with the head of the corresponding metatarsal bone; the base of the middle or distal phalanx articulates with the head of the next most proximal phalanx the slender shaft of the phalanx also known as the diaph

ysis; the body of the distal phalanx is very short ( N341 , N354 , TG6-06A , TG6-06B ) the articulation between the ala of the sacrum and the auricular surface of the ilium a synovial joint; the fibrous articular capsule is thickened dorsally and ventrally to form the sacroiliac ligaments; because of the interlocking nature of the joint surfaces and the strong sacroiliac ligaments, only limited movement is permitted at the sacroiliac joint greater sciatic foramen the passageway for structures entering or leaving the pelvis the piriformis m.

occupies this space along with all lower limb vessels and nerves entering the gluteal region lateral compartment (gluteal), thigh located posterolateral to hip joint contains: tensor fasciae latae m., gluteus maximus, medius & minimis mm., piriformis m., superior & inferior gemellus mm., quadratus femoris m.; obturator internus tendon lesser sciatic foramen the passageway for structures entering or leaving the perineum posterior compartment (hamstring), thigh contains: semimembranosus, semitendinosus, biceps femoris mm.; sciatic nerve adductor canal anterior - sartorius, lateral - vastus medialis, posterior - adductor longus & magnus; ends distally at adductor hiatus contains femoral a. & v., saphenous nerve & nerve to vastus medialis m.

adductor hiatus ( N493 , TG3-21 ) medial - tendon of adductor magnus to adductor tubercle, lateral - insertion of adductor magnus into linea aspera, inferior - femur femoral vessels pass through it to reach the posterior surface of the leg, becoming popliteal vessels (Latin, hiatus = to yawn) anterior compartment (extensor), thigh contains quadriceps femoris and sartorius mm.

pes anserinus adjacent insertions of sartorius, gracilis, and semitendinosus on proximal tibia medial to tibial tuberosity (Latin, pes = foot, anserinus = of the goose) femoral canal ( N262 , TG3-18A , TG3-18B ) location: medial compartment of the femoral sheath, deep to inguinal ligament; opens into the abdominal cavity superiorly at femoral ring may be the site of a femoral hernia; usually contains a deep inguinal lymph node (node of Cloquet) femoral ring medial - lacunar ligament, lateral - fascia on femoral vein, anterior - inguinal ligament, posterior - iliopectineal fascia opening from abdominal cavity into the femoral canal femoral sheath lateral compartment- for the femoral a. intermediate compartment- for the femoral v. medial compartment- the femoral canal does not enclose the femoral nerve femoral triangle superior - inguinal ligament, lateral - sartorius, medial - medial edge of adductor longus m. contains femoral a., v.

& femoral nerve branches; authors disagree on the medial boundary of this triangle Hunter's canal ( N495 , TG3-31 ) superomedial - tendons of semimembranosus & semitendinosus, superolateral - tendon of biceps femoris, inferior - medial & lateral heads of gastrocnemius contains: popliteal a. & v. and their branches; tibial and common fibular nn.; popliteus m. (Latin, poples = the back of the knee) posterior compartment (flexor), leg tibia, fibula, interosseous membrane, posterior intermuscular septum contains: superficially - gastrocnemius, soleus, plantaris mm.; deeply - popliteus, tibialis posterior, flexor digitorum longus, flexor hallucis longus mm.; also contains posterior tibial vessels & tibial n.

fascia, crural ( N544 , TG3-03 ) deep fascia forming tubular investment of leg continuous with fascia lata at knee; connected to fibula by anterior & posterior intermuscular septa; thickened near ankle as extensor & flexor retinacula (Latin, crural = the legs) flexor retinaculum ( N519 , TG3-37 ) tibia, fibula, interosseous membrane, anterior intermuscular septum contains tibialis anterior, extensor hallucis longus, extensor digitorum longus, fibularis tertius; also anterior tibial artery, deep fibular nerve extensor retinaculum, superior ( N530 , TG3-45 ) strong band of deep fascia passing from the fibula to the tibia, proximal to the malleoli binds down the tendons of the muscles in the anterior compartment, preventing bowstringing during dorsiflexion of the ankle (Latin, retinaculum = a band or halter) extensor retinaculum, inferior ( N530 , TG3-45 ) a Y-shaped band of fascia attached

 laterally to the anterosuperior surface of the calcaneus forms a strong loop around the tendons of the fibularis tertius and extensor digitorum longus muscles (Latin, retinaculum = a band or halter) fibular retinaculum, superior a band of deep fascia that extends from the tip of the lateral malleolus to the calcaneus binds down the tendons of the fibularis longus and brevis (Latin, retinaculum = a band or halter) lateral compartment (evertor), leg anterior & posterior intermuscular septa, fibula contains: fibularis longus & brevis mm.; superficial fibular nerve calcaneometatarsal ligament deep fascia forming an investment of the plantar surface of the lateral compartment of the foot continuous with the plantar aponeurosis plantar aponeurosis deep fascia forming an investment of the plantar surface of the central and medial compartments of the foot continuous with the calcaneometatarsal ligament medial compartment, foot ( N533 , TG3-49 ) compartment of the great toe contains: abductor hallucis and flexor hallucis brevis mm., tendon of flex

or hallucis longus m., medial plantar a., v., & n.

lateral compartment, foot compartment of the little (5th) toe contains: abductor digiti minimi and flexor digiti minimi brevis mm., branches of lateral plantar a., v., & n. central compartment, foot ( N533 , TG3-49 ) associated with the lateral 4 toes contains: flexor digitorum brevis & quadratus plantae mm. & lumbrical mm., tendons of flexor digitorum longus m., branches of lateral plantar a., v., & n. adductor-interosseous compartment, foot deepest of the foot compartments contains: adductor hallucis & plantar & dorsal interossei mm., deep branch of lateral plantar n. & plantar arterial arch medial longitudinal arch, foot formed by talus, navicular, cuneiforms, medial 3 metatarsals supported by spring ligament (plantar calcaneonavicular), assisted by tibialis anterior m. lateral longitudinal arch, foot formed by calcaneus, cuboid, lat. 2 metatarsals supported by long & short plantar ligaments, assisted by fibularis longus m.

transverse arch, foot supported by long & short plantar ligaments, assisted by fibularis longus & tibialis anterior & posterior mm.

tarsal sinus straight head: anterior inferior iliac spine; reflected head: above superior rim of acetabulum patella and tibial tuberosity (via patellar ligament) extends leg, flexes thigh rectus femoris is part of the quadriceps femoris muscle vastus lateralis lateral intermuscular septum, lateral lip of linea aspera and gluteal tuberosity patella and lateral patellar retinaculum extends leg vastus lateralis is part of the quadriceps femoris muscle (Latin, vastus = huge) vastus medialis medial intermuscular septum, medial lip of linea aspera patella and medial patellar retinaculum extends leg vastus medialis is part of the quadriceps femoris muscle (Latin, vastus = huge) vastus intermedius anterior and lateral surface of femur patella posterior surface of head & upper shaft of fibula, soleal line of tibia dorsum of calcaneus via the calcaneal (Achilles') tendon plantarflexes foot tibial nerve soleus and the 2 heads of gastrocnemius are sometimes called the triceps surae muscle (Latin, soleus = sole of the foot) pop

liteus lateral condyle of femur (via a round tendon) posterior surface of tibia above soleal line flexes and rotates leg medially (with foot planted, rotates thigh laterally) tibial nerve popliteus unlocks the knee joint to initiate flexion of the leg (Latin, poples = the back of the knee) flexor hallucis longus lower two/thirds of posterior surface of fibula base of distal phalanx of hallux flexes metatarsophalangeal and proximal interphalangeal joints of hallux; plantarflexes foot tibial nerve flexor hallucis longus is very important in the "push off" part of the normal gait (Latin, hallex = great toe) flexor digitorum longus middle half of posterior surface of tibia bases of distal phalanges of digits 2-5 flexes metatarsophalangeal, proximal interphalangeal and distal interphalangeal joints of digits 2-5; plantarflexes foot tibial nerve flexor digitorum longus in the leg is equivalent to the flexor digitorum profundus m.

of the arm tibialis posterior interosseous membrane, posteromedial surface of fibula, posterolateral surface of tibia tuberosity of navicular & medial cuneiform, metatarsals 2-4 plantarflexes foot and inverts foot tibial nerve acts as both an antagonist (dorsiflexion/plantar flexion) and a synergist (inversion) of tibialis anterior ( N499 , TG3-25A , TG3-25B ) lumbosacral trunk (ventral primary rami of L4-L5), ventral primary rami of S1-S4 superior & inferior gluteal nn., n. to obturator internus, n. to quadratus femoris, sciatic n., n. to piriformis, posterior femoral cutaneous n., pudendal n., n. to pelvic diaphragm, pelvic splanchnic nn. mm.

of pelvic & urogenital diaphragm, posterior hip, posterior thigh, leg & foot skin of perineum, posterior thigh, leg & foot (excluding medial side of leg & foot) (Latin, plexus = a braid, a network of nerves, blood vessels or lymphatic vessels) pudendal sacral plexus (ventral primary rami of S2-S4) inferior rectal n., perineal n., dorsal n. of clitoris/penis its branches supply: external anal sphincter, bulbospongiosus, ischiocavernosus, superficial & deep transverse perineus, sphincter urethrae, sphincter urethrovaginalis, compressor urethrae its branches supply: skin of anus, posterior scrotum/labum majus, clitoris/penis passes through pudendal canal formed by fascia on the medial surface of the obturator internus m.

( Latin, pudendus = ashamed, the term referred to "the shameful parts".) to obturator internus sacral plexus (ventral primary rami of L5, S1-S2) obturator internus, superior gemellus sacral plexus (ventral primary rami of L5, S1-S2) gluteus maximus passes through greater sciatic foramen inferior to piriformis m. gluteal, superior sacral plexus (ventral primary rami of L4-L5, S1) superior & inferior brs. gluteus medius & minimus, tensor fasciae latae passes through greater sciatic foramen superior to piriformis m. femoral ( N500 , N544 , TG3-24 , TG3-63 ) lumbar plexus (ventral primary rami of L2-L4) anterior femoral cutaneous brs., saphenous n., nn.

to: sartorius, rectus femoris, vastus lateralis, vastus intermedius, vastus medialis, pectineus sartorius, rectus femoris, vastus lateralis, vastus intermedius, vastus medialis, pectineus skin of anterior thigh passes under inguinal ligament lateral to femoral a. femoral cutaneous, anterior sacral plexus (ventral primary rami of L4-L5, S1-S3) tibial, common fibular (peroneal) (via its tibial & common fibular branches) semitendinosus, semimembranosus, biceps femoris, ischioconylar part of adductor magnus, muscles of leg & foot skin of leg & foot (excluding medial side of leg & foot) sciatic has no direct muscular brs., only 2 terminal brs. - tibial & common fibular nn. fibular, common sciatic lateral sural cutaneous, superficial and deep fibular nn.

short head of biceps femoris; superficial fibular br.: muscles of lateral compartment of leg (fibularis longus and brevis mm.); deep fibular br.: mm. of anterior compartment of leg (tibialis anterior, extensor hallucis longus, extensor digitorum longus, fibularis tertius); mm. of dorsum of foot (extensor digitorum brevis and extensor hallucis brevis) superficial fibular: distal 1/3 of anterior leg; dorsum of foot excluding web between great toe and 2nd toe and distal interphalangeal segments of all toes; deep fibular: skin of the web between great and 2nd toes peroneal is old terminology which has been replaced by fibular fibular, superficial common fibular one proper digital br. to the 1st and 2nd toes mm. of anterior compartment of leg (tibialis anterior, extensor hallucis longus, extensor digitorum longus, fibularis tertius); mm.

of dorsum of foot (extensor digitorum brevis and extensor hallucis brevis) skin of the web between great and 2nd toes peroneal is old terminology which has been replaced by fibular tibial sciatic medial sural cutaneous, medial calcaneal brs., medial & lateral plantar nn. semimembranosus, semitendinosus, long head of biceps femoris, ischiocondylar portion of adductor magnus; mm. of superficial and deep posterior compartments of leg (gastrocnemius, soleus, plantaris, tibialis posterior, flexor hallucis longus, flexor digitorum longus); muscles of plantar side of the foot gluteus maximus, medius & minimus, hip joint internal pudendal ( N499 , TG3-26 ) internal iliac a., anterior division inferior rectal a., perineal a., artery of the bulb of the clitoris/penis, urethral a., deep clitoral/penile a., dorsal clitoral/penile a.

anus, muscles of the superficial and deep perineal spaces, clitoris/penis, posterior aspect of the scrotum/labium majus internal pudendal a. is the primary blood supply to the perineum ( Latin, pudendus = ashamed, the term referred to "the shameful parts".) internal iliac a., anterior division pubic br., acetabular br., anterior br., posterior br. medial thigh and hip anterior and posterior brs. pass on the anterior and posterior sides of the adductor brevis m.; aberrant obturator a. arises from the inferior epigastric a. in 30% of cases femoral external iliac superficial epigastric a., superficial circumflex iliac a., superficial & deep external pudendal aa., deep femoral, descending genicular, popliteal thigh, leg & foot the femoral a. is continuous with the popliteal a.; the name change occurs at the adductor hiatus femoral, deep anterior & posterior tibial; 5 genicular brs. knee, leg & foot the popliteal a.

is the continuation of the femoral a.; the name change occurs at the adductor hiatus (Latin, poples = the back of the knee) genicular, middle popliteal cruciate ligaments & deep structures of knee anastomoses with other genicular brs. of popliteal a., circumflex fibular a. & anterior tibial recurrent a. to form genicular anastomosis (Latin, genicular = to bend around the knee) genicular, superior lateral popliteal lateral aspect of knee anastomoses with other genicular brs. of popliteal a., circumflex fibular a. & anterior tibial recurrent a. to form genicular anastomosis (Latin, genicular = to bend around the knee) genicular, superior medial popliteal medial aspect of knee anastomoses with other genicular brs. of popliteal a., circumflex fibular a. & anterior tibial recurrent a.

to form genicular anastomosis (Latin, genicular = to bend around the knee) tibial, posterior ( N518 , TG3-38AB ) popliteal fibular (peroneal), circumflex fibular, nutrient a. of tibia, communicating br., posterior medial malleolar brs., medial calcaneal brs., lateral & medial plantar aa. posterior & lateral leg, plantar aspect of foot posterior tibial bifurcates on the medial side of the foot to give rise to the medial and lateral plantar aa. fibular Clinical Terms of the hip & thigh Term Definition sciatica A syndrome characterized by pain radiating from the back into the buttock and into the lower extremity along its posterior or lateral aspect and most commonly caused by prolapse of the intervertebral disk; the term is also used to refer to pain anywhere along the course of the sciatic nerve.

avascular necrosis Loss of the arterial supply to an epiphysis or other parts of a bone resulting in death of bone tissue hip prosthesis replacement for a hip joint Trendelenburg sign/gluteal gait When a person with paralysis of the superior gluteal nerve is asked to stand on one leg, the pelvis on the unsupported side descends indicating that the gluteus medius on the supported side is weak or nonfunctional. This clinical observation is a positive Trendelenburg sign. ischial bursitis recurrent microtrauma (i.e. from cycling) results in inflammation of the bursa; calcification in the bursa may occur with chronic bursitis. Localized pain occurs over the bursa, and the pain increases with movement of the gluteal maximus. Ischial bursitis ("weaver's bottom") is a friction bursitis resulting from excessive friction between the ischial bursae and ischial tuberosities. trochanteric bursitis Often results from repetitive actions such as climbing stairs when carrying heavy objects or running on a steeply elevated treadmill.

These movements involve the gluteus maximus and move the superior tendinous fibers repeatedly back and forth over the bursa of the greater trochanter. Trochanteric bursitis causes deep diffuse pain in the lateral thigh region. This type of friction bursitis is characterized by point tenderness over the greater trochanter. The pain radiates along the iliotibial tract that extends from the iliac tubercle to the tibia. The thickening of the fascia lata receives tendinous reinforcements from the tensor of the fascia lata and the gluteus maximus. The pain from an inflamed trochanteric bursa, usually localized just posterior to the greater trochanter, is usually elicited by manually resisting abduction and lateral rotation of the thigh while the person is lying on the unaffected side. femoral hernia a protrusion of abdominal viscera through the femoral ring into the femoral canal. A femoral hernia appears as a mass, often tender, in the femoral triangle, inferolateral to the pubic tubercle. The hernia is bounded by the femoral vein laterally and the lacunar ligament medially.

Femoral hernias are more common in females, whereas inguinal hernias occur more commonly in males. Strangulation of the femoral hernia may occur particularly due to the lacunar ligament. This condition can be treated by excising the lacunar ligament. (Latin, hernia = to rupture) obturator hernia Understanding The Anatomy of the Bones of the Foot Understanding The Anatomy of the Bones of the Foot Authored by Hindfoot & Tarsal Bones Over 25 percent of our bones are located in our feet. There are twenty-six bones that make up the complex structure of each foot. The foot is a strong mechanism, and it supports our entire body weight during all upright activities (standing, walking, running, etc). It remains flexible, durable, and resilient under enormous pressure. Structurally, the foot consists of three main parts: the forefoot, midfoot, and hindfoot. Anatomically, the bones of the foot are known as the tarsal bones, metatarsal bones, and phalanges. Let’s break down each category and discuss the importance of each bone. Forefoot: Phalanges and Metatarsal Bones The forefoot comprises fourteen phalanges and five metatarsal bones.

One phalanx of each of the five toes connects to one of the five metatarsals. The toes are numbered one through five, starting with the big toe, which is technically known as the hallux. Some people like to call the fifth toe the “pinky.” The phalanges are referred to as follows: The proximal phalanx is the base of each toe and articulates the metatarsal bone and middle phalanx. The middle phalanx is located under the distal phalanx in the second, third, fourth and fifth toes only. The hallux does not have a middle phalanx. The distal phalanx is found at the end of each toe, forming the tip of the toes. There are five metatarsals in each foot. The metatarsals are the long bones located between the tarsal bones and the phalanges. Each metatarsal has a long shaft with two expanded ends called the base and the head. They form part of the foot’s arch and serve both as a major shock absorber and a weight-transfer mechanism. They are connected to the forefoot and midfoot by muscles, tendons, and a special ligament known as the plantar fascia.

The metatarsals are not named individually; rather, they are numbered first through fifth, starting with the big toe. Here is a quick description of each of the metatarsal bones: The first metatarsal bone is the shortest and thickest. The second metatarsal bone is the longest and is firmly held between the first and third cuneiform bones. This bone is most susceptible to injury. The third metatarsal bone is in the middle and articulates the third cuneiform, as well as the second and fourth metatarsal bones. The fourth metatarsal bone is smaller than the third, but like the third it also articulates the surrounding metatarsals (the third and fifth), and also articulates the cuboid. The fifth metatarsal bone articulates the cuboid and the fourth metatarsal. Jones fractures and stress fractures are common injuries to this bone. There are also two tiny bones located under the hallux (big toe) called sesamoid bones. Sesamoid bones develop within the tendon of a muscle to protect the tendon from wear and tear at the point where it passes over the end of the metatarsal bone. They bear the weight of the body when the toe pushes off in walking or running.

Though it is less common, sesamoid bones can be found elsewhere in the foot within other flexor tendons of the toes. Midfoot: Lesser Tarsal Bones The five bones that make up the midfoot are collectively known as the lesser tarsal bones. They act as an intermediary to transfer weight from the hindfoot to the forefoot with each footstep. These bones, along with the joints and ligaments that connect them, make up most of what we would consider the arch of the foot. They include: The navicular bone is boat-shaped and located in the middle of the foot. It articulates with the talus and the three cuneiform bones. The cuboid bone is shaped like a cube and is the last of the seven tarsal bones, articulating with the fourth and fifth metatarsal bones, calcaneus, and navicular bones. There are three cuneiform bones in all: medial, intermediate, and lateral. They are located in the midfoot region, articulating with the corresponding metatarsal bones and navicular bone.

Hindfoot: Greater Tarsal bones The hindfoot connects the foot to the leg at the ankle joint, and comprises two large bones called the talus and calcaneus. These bones articulate with each other through the subtalar joint, and also link the hindfoot to the midfoot through the mid-tarsal joint. Here is a brief description of each of the tarsal bones: The talus connects the hindfoot to the two leg bones (the tibia and fibula) to form the ankle joint, which acts as a hinge to allow the foot to move up and down. It also links the hindfoot to the midfoot through the navicular bone to form one part of the mid-tarsal joint. From below, the talus meets up with the calcaneus to form the subtalar joint, which allows the foot to move from side to side. The calcaneus is also known as the heel bone, and it is the largest bone in the foot. It connects with the talus from above to form the subtalar joint. It also meets up with the cuboid bone to form the rest of the midtarsal joint.

This joint allows some motion between the hindfoot and midfoot that gives the foot some flexibility Medical References: H.F. Fullmann "Atlas of Anatomy" (Tandem Verlag GmbH, 2009) 100-101 Professor P. Abrahams "A Complete Guide to How the Body Works, The Atlas of the Human Body" (Amber Books, 2009) 222-224 Taber's Cyclopedic Medical Dictionary, 21 edition (F.A.

Davis Company, 2005) 893 This page was last updated on October 2nd, 2015 How To Maintain & Improve Your Foot Health A Complete Guide To The Anatomy Of The Foot Anatomy - Lecture 4: Lower Limbs - Anatomy And Cell Biology 135 with Camps at University of California - Santa Cruz - StudyBlue - Interpubic disc + adjacent region of each pubic bone - Interpubic disc = a pad of fibrocartilage; where hip bones join at the bottom Greater pelvis - AKA false pelvis - Separated from the lesser pelvis by the plane from the pubic symphysis to the sacral promontory (most forward part of the sacrum) - Superior to the pelvic brim Lesser pelvis - AKA true pelvis - Separated from the greater pelvis by a plane from the pubic symphysis to the sacral promontory (most forward part of the sacrum) - Contains pelvic organs (bladder, internal reproductive organs) - Inferior to the pelvic brim - Feature = pelvic inlet, pelvic outlet, and pelvic brim Pelvic brim - A round margin that separates the greater and lesser pelvis Pelvic inlet

 - The opening circumscribed by the pelvic brim - The entry into the lesser pelvis - Where the infant's head passes during birth Pelvic outlet - Lower margin of the lesser pelvis 3 distinctive features of Hip bones - Iliac crest - Supports the body when sitting Ramus - Joins the inferior ramus of the pubis anteriorly Pubis - Most anterior position of the hip bone - Serves as a platform for the bladder - Feature = Superior + inferior ramus + triangular body Sexual Dimorphism - The pelvis - Male = heavier and thicker due to forces from strong muscles - Female = Adapted for pregnancy and childbirth; wider and shallower; larger pelvic inlet and outlet for passage of the infant's head Lower Limb - Adapted for weight bearing and locomotion - 30 bones/limb - 4 bones = femoral region, crural region, tarsal region, and pedal region Femoral region - Region of the lower limb - AKA thigh - Extends from hip to knee - Contains the femur and patella Crural region - Region of the lower limb - AKA leg - Intertrochanteric crest connects the trochanters to the posterior side of the femur - Intertrochan

teric line connects the trochanter to the anterior side Intertrochanteric Crest - A thick oblique ridge of the bone - Connects to the greater and lesser trochanter on the POSTERIOR side Intertrochanteric line - Connects the greater and lesser trochanters on the ANTERIOR side Linea aspera - Feature of the femur diaphysis - A posterior ridge at the midpoint of the femur - At the upper end, it forks into a spiral line (medial) and a gluteal tuberosity (lateral) - At lower end, it forks into medial and lateral supracondylar lines (continues down to the respective epicondyles) Gluteal tuberosity - Feature of the femur diaphysis - A rough ridge - Attachment for the gluteus maximus Epicondyles Articular facets of the patella - A pair of shallow articular facets - On posterior surface - Lateral facet is usually larger than the medial Tibia - One of two bones of the leg - Only weight bearing bone of the crural region - Features = medial/lateral condyles, intercondylar eminence, tibial tuberosity, anterior crest

, and medial/lateral malleolus Condyles of the Tibia - Separated by the intercondylar eminence - Articulate with the condyles of the femur Tibial tuberosity - The rough anterior surface of the tibia, just below the patella - Attachment for thigh muscles (straighten the knee) Anterior crest - Sharp and angular, on the shin Malleoli - Only the medial malleolus is part of the tibula; lateral malleolus is part of the fibula - Medial and lateral malleoli - A prominent bony knob on each side of the ankle Fibula - Does not bear any of the body's weight; can be used for bone graft - Feature = head, lateral malleolus, interosseous membrane Head of the Fibula - Connects to the tibia at the proximal tibiofibular joint - Apex = point of the head Tarsal Bones - Bones in the tarsal region/ankle - Features = calcaneus, calcaneal tendon, talus, trochlear surface, cuneiforms, cuboid Calcaneus - Numbered medial to lateral ( I to V) - Metatarsal I artic

ulates with big toe - Feature = Head, body, and base Hallux - Contains only two bones = proximal and distal phalanx I Bipedalism - Skeletal adaptations = Skull, spine, upper limbs, hip, lower limbs, and foot Skull adaptations for bipedality - Cervical curvature + skull remodeling = balance human skull on vertebral column - Foramen magnum moved to more inferior + anterior location compared to apes - Face is flatter = less weight anterior to the occipital condyles Spine modifications for bipedalism - H.

spine = lumbar curvature, S shaped, can shift the body's center of gravity to the rear, above and slightly behind the hip joint - A. spine = C shaped, COG is anterior to the hip joint when standing, constantly exerting energy to stay upright - - H. pectoral girdle and wrist joints = greater mobility - H. have shorter arms - H. adapted to reaching out, exploring the environment Hip modifications for bipedalism - Posterior growth of the ilium = very deeply concave greater sciatic notch - Gluteal muscles + hip modification = efficient stride - Bowl-shaped = hold/protect viscera Gluteal muscles in bipedalism - Gluteus maximus, medius and minimus - G. maximus = thigh abductor (moves laterally), originates behind the hip joint, pulls the thigh back in the second half of a stride - Minimus/medius = O at ilium and I at greater trochanter of femur, extends laterally - These muscles shift the body weight to the planted foot when walking Lower limb modifications for bipedalism - H.

femurs = angle medially from the hip to the knee, brings knees closer and under COG - H. lock knees = maintain erect posture wihtout much muscular effort Feet modifications for bipedalism - H. tarsal bones = tightly articulated with one another - H. calcaneus = strongly developed - H. hallux = not opposable, "toe-off" (pushes body forward in the last phase of the stride), crippling if lost - H. 3 arches = distribute body's weight over calcaneus and metatarsal bones; absorbs stress of walking Arches for bipedalism Functional Anatomy- Foot and Ankle - College Of Health Sciences 5002 with Dr. Walter Childers at Alabama State University - StudyBlue Good to have you back! If you've signed in to StudyBlue with Facebook in the past, please do that again. Functional Anatomy- Foot and Ankle Functional Anatomy- Foot and Ankle Breanna H. Has to be flexible to absorb shock Has to be rigid to act as a level for propulsion Absorb shock Act as a lever for propulsion Rigid What are the 2 functions of the foot? Advertisement ) What bones make up the rearfoot?

Tarsals What bones make up the midfoot? Metatarsals What bones make up the forefoot? Pes Planus Foot arches are raised and looks like a cave Pronation Decrease of the foot arches Supination Look down and rotate your toes out Ex: Walking like a duck Adduction Look down and rotate your toes in. Ex: Pigeon Toed. Roll your heel outward Talocrural Joint The articulation of the trochlea (dome) and sides of the talus with the rectangular cavity formed by the distal end of the tibia and both malleoli. Often referred to as the "mortise," owing to its resemblance to the wood joint used by carpenters. Advertisement The talus rolls forward relative to the leg as it simultaneously slides posteriorly. Anterior Talofibular Ligament is slackened, while the achilles tendon is taut. Plantarflexion: The talus rolls posteriorly and slides anteriorly. Achilles tendon is slackened while the anterior talofibular ligament is taut. Dorsiflexion: The talus rolls forward and slides posteriorly. Anterior Talofibular Ligament is slackened, while the achilles tendon is taut.

Plantarflexion: The talus rolls posteriorly and slides anteriorly. Achilles tendon is slackened while the anterior talofibular ligament is taut. Describe the arthrokinematics of the talocrural joint. Talocrural Joint One degree of freedom Motion occurs around an axis of rotation that passes through the body of the talus and through the tips of both malleoli. Because the lateral malleolus is inferior and posterior to the medial malleolus, the axis of rotation departs slightly from a pure medial-lateral axis. The axis deviates from a pure medial-lateral axis: About 10 degrees in the frontal plane About 6 degrees in the horizontal plane. Talocrural Joint Axis Ankle joint instanteous center of rotation Just distal to the distal tip of the fibula Subtalar Joint Abduction/Adduction Subtalar Joint The arthrokinematics of this joint involve a sliding motion among the 3 sets of facets, yielding a curvilinear arc of movement between the calcaneus and the talus.

The axis of rotation is typically described as a line that pierces the lateral the lateral-posterior heel and courses through this joint in anterior, medial, and superior directions. Abduction/adduction (vertical axis): 42 degrees from the AP axis Dorsiflexion/plantarflexion (ML axis): 16 degrees from the AP axis Abduction/adduction (vertical axis): 42 degrees from the AP axis Dorsiflexion/plantarflexion (ML axis): 16 degrees from the AP axis Where is the axis of rotation positioned in the subtalar joint? About 10 degrees in the frontal plane About 6 degrees in the horizontal plane. Where is the axis of rotation positioned in the talocrural joint? Inversion Subtalar Joint- Expect tears on the lateral side. You can rip off the tip of the fibula if you really injure it. Transverse Tarsal Joint Located in the midfoot Also known as the mid tarsal joint (consists of talonavicular joint and calcaneocuboid joint). Most versatile joint of the foot that moves through a more oblique path of motion, cutting nearly equally through all 3 cardinal planes.

Allows the weight bearing foot to adapt to a variety of surface contours. Transverse Tarsal Joint Abduction/Adduction (Vertical Axis): 52 degrees from the Eversion/Inversion (AP axis) Dorsiflexion/Plantarflexion (ML axis): 57 degrees from Eversion/Inversion (AP axis) Abduction and Dorsiflexion What are the 2 main components of pronation? Adduction and Plantarflexion What are the 2 main components of Supination? Metatarsophalangeal Joint Not purely flexion/extension in the sagittal plane Dorsiflexion What are the functions of tibialis anterior? Located anterior to the talocrural axis. Plantarflexion What are the actions of tibialis posterior and achilles tendon? Both are posterior to the talocrural joint. Dorsiflexion What are the actions of Extensor Digitorum Longus and Fibularis Tertius? Both are anterior to the talocrural joint. Plantarflexion What are the functions of fibularis brevis and fibularis longus? Both are posterior to the talocural joint.

Triceps Surae ~65% of ankle plantar flexion movement Major mover of the ankle joint Tibialis Anterior Dorsiflexor, inversion, “shin splints” Very active eccentrically to when the heel hits the ground to when the forefoot hits the ground. Mostly type 2 fibers and fatigue very fast. Tibialis Anterior Paralysis Injury to deep branch of the Peroneal/Fibularis nerve Ankle Foot Orthosis Walkaide Triceps Surae Act through the Achilles tendon. The Achilles tendon gives the muscles stretch when you are contracting eccentrically (pushing off). Soleus- single joint ankle plantarflexer Gastrocnemius- 2 joint muscle (knee flexor and ankle extensor) By contracting the medial and lateral heads differently, you will change the way your foot moves (invert, evert, plantarflexion, dorsiflexion). Ex: If you contract the medial head, the foot will invert. Tibialis Anterior Muscle comes under the superior extensor retinaculum and then it continues on to insert on the base of the 1st metatarsal and media cuneiform.

Makes an affective pull on the ankle joint because it passes under the retinaculum. Gait- When your heel fits the ground, then your forefoot hits. The TA fires eccentrically to lower the forefoot in a controlled manner to the ground. Essentially contracts to lower the forefoot after the heel hits the ground. Plantar Fascia During Gait Your absorbing impact when you are first landing. When you push off, your don’t want it to be really loose. Initial contact- nothing is very rigid; it absorbs a lot of energy. If you internally rotate, the arch will collapse and is really good at absorbing impact. As your foot hits the ground, you externally rotate but immediately internally rotate to absorb the energy and collapse the arch like one big sponge of mechanical energy. Medial Longitudinal Arch This arch is very tall (which is why the medial side of the foot is missing from a footprint ) and is extremely resilient due to its large number of component bones. Can be defined in terms of its apex (the trochlear surface of the talus) and its two extremities which are the medial tubercle of the calcaneum and the heads of metatarsals 1-3. curves above the ground.

It is made up by the calcaneus, the talus, the navicular, the three cuneiforms, and the first, second, and third metatarsals. Lateral Longitudinal Arch The extremities are the lateral tubercle of the calcaneum and the heads of metatarsals 4-5. This arch is flat and contains relatively few bones. very low. It is composed of the calcaneus, the cuboid, and the fourth and fifth metatarsals. Its summit is at the talocalcaneal articulation, and its chief joint is the calcaneocuboid, which possesses a special mechanism for locking and allows only a limited movement. Transverse Arch not a true arch, it can be seen to best advantage in the region of the cuneiform bones. This arch is maintained by the same muscles and ligaments as the longitudinal arches. The bony fit is particularly good. Arches of the foot When all of the arches are up, the foot is very rigid. When the arches are down, there is no real structure to it and you can absorb all of the impact. Eventually, you want to bring the arches back up so you have something to push off with.

As you externally rotate, you bring the arches up. Plantar Fascia Thick band of fascia connecting the calcaneous to the metatarsals Windlass mechanism

Question: Latin/anotomical 'Pes', what part of the body contains the talus and calcaneus bones?
Answer: Foot