Anatomy: Bones of Lower Extremity

Post-patellectomy quads are how efficient?

60% efficient.

Intercondylar eminence

ACL and PCL fit here

Talocrural joint

Ankle.

Tibial Tuberosity

Anterior bump below patella. Bumping it causes reflex extension of the knee.

Anterior-Superior Iliac spine

Anterior-most projection near the top of the acetabulum that extends out over pubis.Attachment for the sartorius.

Apex of sacrum

Area at the bottom of the sacrum that narrows. Directly superior to the coccyx.

Intercondylar fossa

Area between the condyles

Superior Articular Process

Articulate with lumbar of spine. Two projections at top of of sacrum.

Tibia

Articulates with femur at knee joint proximally and with Talus distally at ankle (talocrural) joint.

Acetabulum

Articulation for the head of the femur takes place here.

Lesser Trochanter.

Attachment for the ileo psoas.

Iliac Fossa

Big, smooth concavity on the ala (wing) of the medial surface of the ilium - forms the posterior wall of the abdominal cavity.

sesamoid bone

Bone enclosed within muscle and tendon (patella)

Calcaneus

Distal most bone forms the posterior support for the weight of the body. Heel bone. Attachment point for achilles tendon. Largest and strongest bone of foot. Articulates with the talus sup. and the cuboid ant.

Lateral malleolus

Distal part of the fibula

Sacrotuberous/sacrospinous ligaments:

Divide the greater and lesser sciatic notches. Both attach to the sacrum.

Ramus of the Ischium

Extends medially from the body and joins inferior ramus of the pubus

Fibula

Forms the lateral half of the Talocrural (ankle) joint. Has little weight-bearing responsibility...function is to hold talus in socket. Does not articulate with the femur.

Transfer of weight from superior to inferior:

From vertebral column to pelvic girdle to hip joints to femurs, to patella and tibia, to talocrural joint (ankle) to the foot to the talus.

Meniscus

Increases joint stability at the knee because tibia and femur are not congruent.

Ischium

Inferior, posterior section of acetabulum.

Superior tibiofibular joint

Knee joint

Ala (sacrum)

L and R wings of sacrum

Patella

Largest sesamoid bone in the body. Formed in the tendon of the quadriceps. Gives the quads a mechanical advantage (similar to that of a pulley/rope system).

Lateral condyle

Lateral dome at bottom of bone.

Anterior Inferior Iliac spine

Less pronounced projection directly inferior to the anterior superior iliac spine.

Inferior Ramus of Pubus

Lines posteriorly inferiorly laterally to join ramus and 1/2 of the pubic arch.

Superior Ramus of Pubis

Lines superiorly and laterally to the acetabulum. Fused to ilium and ischium.

Lower extremity functions

Locomotion, weight support, maintain equillibrium. Sacrifices mobility for stability.

Femur

Longest and strongest long bone in the body.

Patellar surface (Trochlea)

Notch where patella fits.

Acetabular Notch

Outer rim of socket

Posterior Inferior Iliac Spine

Projection immediately below the posterior superior iliac spine.

Ischial spine

Projects medially and separates the greater/lesser sciatic notches. Sharp point on posterior end of acetabulum.

Intertrochanteric crest

Ridge that unites trochanters.

Linea aspera

Rough ridge of bone on posterior surface. Serves as the attachment site for the adductor brevis and magnus.

Obturator foramen

Round for men, ovular for females. Opening formed by the bodies and rami of the pubis and ischium.

Medial Mallelous

Saddle shape, extends distal to the shapt of the tibia to make 1/2 of the talocrural joint. Forms bump on medial side of ankle.

Posterior Superior Iliac Spine

Skin dimple on back. Superior-most projection on posterior end of Ilium.

Lateral epicondyle

Small elevation above lateral condyle.

Medial Epicondyle

Small elevation above medial condyle.

Nutrient foramen

Small hole, allows passage of nutrient arteries. Largest foramen in body.

Anterior Foramina

Small openings which are for sacral nerves.

Lesser Sciatic notch

Smaller notch inferior to Greater Sciatic notch

Auricular Surface

Smooth surface on the ilium that is covered with cartilage for articulation with the sacrum to form the SI joint.

Ilium

Superior part of acetabulum.

Adductor Tubercle

Superior part of the medial femoral condyle. Attachment site for adductor magnus.

3 kinds of bones in foot

Tarsals, metatarsals, phalanges

Ala

The interior portion of the ilium between the iliac crest and the iliac fossa. "Wing" of ilium.

Iliac crest

Top edge of ilium that projects outward. Bony part of hip that you can feel with your hand.

Greater Trochanter

Top left knob of femur next to head. Attachment for gleuteal ms.

Body of ischium

Topmost, thick section of Ischium. Fused with the ilium and the pubis.

Coccyx

Triangular structure at bottom of sacrum (tailbone). Remnant of the tall 3-5 vertebrae. Curves more anteriorly in males than females. No body weight support, but bleuteus maximus and coccygeus attach here.

Sacrum

Wedge shaped bone at base of spine made of 3-5 fused vertebrae. Named after a "holy thing or place/ a sacrifice or victim" from the time of the burning of the witches. Provides strength and stability to pelvis. Transmits the weight of the upper body through the SI joints.

Ischial tuberosity

What you sit on, covered by your ass. Rough, rounded edge at inferior-most part of ischium. Attachment point for the hams and the sacrotuberous ligament.

Head of femur

articulates in the acetabulum.

Navicular

articulates with the talus and the 3 cuneiforms - facets for articulations with all three.

Inferior tibiofibular joint

at ankle. (AKA mortise)

Pelvic girdle

bony ring formed by the hip bones and the sacrum. Provides transition point from spine to lower extremities.

Transverse acetabular ligament

bridges the acetabular notch

Filum terminale passageway

comes down through the sacral hiatus and attaches at bottom

Sacroiliac joint

connects sacrum to ilium

Ligamentum teres

connects to the head of the femur. Contributes only minimally to the stability of the hip.

Greater Sciatic notch

deep notch inferior to SI joint. For sciatic nerve passage

Acetabular Fossa

depression where the head of the femur attaches - refers to the inner horseshoe-shaped depression where joint is. Lined with the labrum.

Soleal line

diagonal line on posterior side of tibia. Superior attachment of the soleus muscle.

Head of Talus

directed anterior-medial and articulates with the navicular and the calcaneus

Thigh contains:

distal femur, patella, and the anterior surface of the knee. Patellafemoral and tibiofemoral articulations

Complete fusion of acetabulum...

does not take place until puberty, completed by around 23.

Cuneiforms

each articulate with the navicular posterior and app. met. anteriorly

Medial/lateral tibial plateau

flat surfaces at top of tibia where condyles fit.

Lateral facet

flatter surface of patella that it sits on.

Distal fibula

forms the lateral malleolus

Acetabulofemoral joint

hip joint (where femoral head meets hip socket)

Fibular head

irregular in shape. Superior facet for articulation with lateral tibial condyle.

Pubic symphysis

joint between 2 pubic bodies - fibrocartilaginous joint

Medial Condyle

medial dome at bottom of bone

Cuboid

most lateral in distal row of the tarsus.

Minimus

name of the anterior trochanter

Medius

name of the superior posterior

Metatarsals

numbered from medial portion of the foot - plantar surface of the first are sesamoid bones both medial and lateral, bear most of the weight during late stance - second is the longest - base of fifth has tuberosity lateral that covers cuboid - provides attachment for peroneus brevis.

Lower leg

region between the inferior knee and the superior ankle.

Mortise

saddle joint in ankle, formed by tibia and fibula (inferior tibiofibular joint)

Sesamoids

sesamoids on the inferior distal surface of the first metatarsal

Trochlea

superior articular surface of talus, inferior surface of tibia

Talus

superior surface articulates with the tibia and fibula to form the talocrural joint. One of the few bones in the body without any muscular attachments. Looks like a saddle when viewed from the dorsum. Distal surface articulates with calcaneus and navicular

Neck of talus

the constricted part between the head and the body. Deep groove for sulcus tali for ligaments to connect talus and calcaneus

Hip

the region from the iliac crest to the mid thigh, contains the inominate, acetabulum, femoral head, upper thigh. Connects axial skeleton to lower limb.

Phalanges

there are 14, all with base, shaft, and head.