2.03 Appendicular Skeleton 2

Os coxae (alternate names)

Coxal bone or innominate bone.

Pelvis (components)

Left and right ossa coxae, sacrum, and coccyx.

Pelvic girdle (components)

Left and right ossa coxae.

Ossa coxae (three fused bones)

Ilium, ischium, and pubis.

Ossa coxae fusion (age and location)

Fuses between ages 13 and 15 at the lunate surface of the acetabulum.

Obturator foramen

Large space bordered by the pubis and ischium.

Iliac crest

Superior ridge of the ilium.

Iliac tubercle

Widest point on the hip, located on the iliac crest.

Iliac spines

Anterior, posterior, superior, and inferior projections on the iliac crest.

Ala of ilium

Wide, fan-shaped portion of the ilium.

Gluteal lines of ilium

Anterior, posterior, and inferior lines serving as lateral sites for muscle attachment.

Greater sciatic notch

Posterior notch located on the ilium.

Ischial spine

Prominent sharp medial process on the ischium.

Ischial tuberosity

Rough inferior projection of ischium that supports the body when seated ("sits bone").

Ischial ramus

Extension from the ischial tuberosity to the pubis.

Pubic rami

Superior and inferior rami extending between acetabulum and ischial ramus.

Pubic crest

Rough ridge on anterosuperior of superior pubic ramus, ending as pubic tubercle.

Iliac fossa

Large depression on the medial surface of the ilium.

Arcuate line

Ridge inferior to the iliac fossa on the medial ilium.

Auricular surface of ilium

Medial articulation site with the sacrum.

Iliac tuberosity

Rough posterior-superior area on the medial ilium.

Lesser sciatic notch

Notch located between the ischial tuberosity and ischial spine.

Pubic symphysis

Joint between the contralateral pubis bones.

Pectineal line of pubis

Medial pubic ridge continuous from the arcuate line, forming part of pelvic brim.

Pelvic brim (boundaries)

Continuous oval ridge formed by pubic crest, pectineal line, arcuate line, and sacral promontory.

True pelvis

Bony basin inferior to pelvic brim containing pelvic organs.

False pelvis

Region superior to pelvic brim, bounded laterally by ilia and anteriorly by abdominal wall.

Pelvic inlet

Superior entrance to true pelvis located at the pelvic brim.

Pelvic outlet

Exit of true pelvis defined by coccyx, ischial tuberosities, and pubic symphysis.

Gynecoid pelvis

Typical female pelvis; most common shape (50%).

Anthropoid pelvis

Narrow and deep pelvis shape with an upright oval pelvic inlet (25%).

Android pelvis

Pelvis shape resembling a male pelvis (20%).

Platypelloid pelvis

Flat pelvis shape; least common (5%).

Male vs. Female pelvis (mass and markings)

Female pelvis is less massive with less prominent muscle markings.

Male vs. Female pelvis (ilia flaring)

Female ilia are laterally flared, resulting in a wider pelvis.

Male vs. Female pelvis (pelvic inlet shape)

Female pelvic inlet is a wide oval; male pelvic inlet is heart-shaped.

Preauricular sulcus

Groove between greater sciatic notch and sacroiliac joint, present in females.

Male vs. Female pelvis (subpubic angle)

Female subpubic angle is ~100°; male subpubic angle is ~90°.

Hip joint (articulating bones)

Os coxae and femur.

Hip joint (main ligaments)

Iliofemoral, ischiofemoral, and pubofemoral ligaments.

Hip joint (internal structures)

Ligament of head of femur and acetabular labrum.

Femur head and fovea

Head articulates at acetabulum; fovea is a pit for ligament attachment.

Femur neck

Constricted region distal to the head of the femur.

Greater and Lesser trochanters

Massive processes for hip/thigh muscle attachments; lesser trochanter is prominent posteriorly.

Intertrochanteric line

Anterior ridge between trochanters marking the distal edge of hip capsule.

Intertrochanteric crest

Thick posterior ridge between greater and lesser trochanters.

Gluteal tuberosity of femur

Posterior rough region where gluteus maximus attaches.

Pectineal line of femur

Ridge medial to gluteal tuberosity for muscle attachment.

Linea aspera

Ridge on posterior shaft of femur for thigh muscle attachments.

Femur (supracondylar lines)

Medial and lateral supracondylar lines are continuations of the linea aspera.

Popliteal surface of femur

Knee pit region where blood vessels and nerves pass superficially.

Intercondylar fossa of femur

Deep posterior depression that separates the medial and lateral condyles.

Femur condyles (medial and lateral)

Smooth rounded articular surfaces for articulation with the tibia.

Femur epicondyles (medial and lateral)

Projections superior to condyles for muscle and ligament attachment.

Adductor tubercle

Projection on the medial epicondyle of femur serving as insertion for adductor magnus.

Patellar surface of femur

Smooth anterior region between condyles where the patella attaches.

Knee joint (menisci and ligaments)

Medial/lateral menisci, intracapsular (ACL/PCL), extracapsular (tibial/medial and fibular/lateral lig.).

Patella (anatomy and type)

Sesamoid bone; triangular with broad superior base and inferior apex attaching to patellar surface.

Proximal tibia muscle insertions

Tibial tuberosity (quads), Gerdy tubercle (TFL), pes anserinus (sartorius, gracilis, semitendinosus).

Tibia proximal condyles

Medial and lateral condyles providing smooth surfaces for femur attachment.

Intercondylar eminence of tibia

Raised region located between the medial and lateral condyles.

Fibular articulation facet on tibia

Smooth area where the head of the fibula attaches proximally.

Tibial tuberosity

Rough anterior projection inferior to condyles; insertion for patellar ligament.

Anterior border of tibia

Prominent ridge along the anterior surface commonly known as the shin.

Soleal line of tibia

Oblique raised line on the posterior surface for muscle attachment.

Fibula proximal structures

Head with flat articular facet attaching to tibia, and narrow neck inferior to head.

Medial malleolus of tibia

Inferior prominent medial process that stabilizes the ankle joint.

Distal tibia features

Inferior articular surface attaching to talus and fibular notch for distal fibular attachment.

Lateral malleolus of fibula

Distal expansion of the fibula that stabilizes the lateral ankle joint.

Tarsal bones mnemonic

"Tall Canadian Navy Medical Interns Lay Chopped Cuties"

Tarsal bones (overview)

7 total: 2 proximal (Talus, Calcaneus), 5 distal (Navicular, Cuboid, 3 Cuneiforms).

Talus

Most superior tarsal bone; articulates directly with the tibia.

Calcaneus

Largest tarsal bone; forms the heel.

Navicular bone

Tarsal bone located on the medial side of the ankle.

Cuneiform bones

Three tarsal bones (medial, intermediate, lateral) arranged in a line.

Cuboid bone

Tarsal bone located on the lateral side of the ankle.

Metatarsals and Phalanges

Numbered I to V (I = big toe/hallux, V = pinky toe); structured like metacarpals.

Ankle joint (bones and ligaments)

Formed by tibia, fibula, and talus; supported by lateral and deltoid ligaments.

Medial longitudinal arch

Highest arch of foot, extending from heel to hallux.

Lateral longitudinal arch

Lowest arch of foot, extending from heel to 5th toe.

Transverse arch of foot

Arch running perpendicular to longitudinal arches along distal row of tarsals.

Iliacus (origin, insertion, action)

O: iliac fossa | I: lesser trochanter of femur | A: flex thigh

Psoas major (origin, insertion, action)

O: T12-L5 vertebrae | I: lesser trochanter of femur | A: flex thigh

Psoas minor (origin, insertion, action)

O: T12-L1 vertebrae | I: pectineal line of pubis | A: flex lumbar vertebrae

Pectineus (origin, insertion, action)

O: pectineal line of pubis | I: pectineal line of femur | A: adduct and flex thigh

Adductor longus (origin, insertion, action)

O: medial pubis | I: linea aspera of femur | A: adduct and flex thigh

Gracilis (origin, insertion, action)

O: inferior ramus and body of pubis | I: pes anserinus | A: adduct/flex thigh and leg

Adductor brevis (action)

Adducts and flexes thigh.

Adductor brevis (origin)

Inferior ramus and body of pubis.

Adductor brevis (insertion)

Linea aspera of femur.

Adductor magnus (action)

Adducts thigh. Adductor part: flexes/medially rotates thigh. Hamstring part: extends/laterally rotates thigh.

Adductor magnus (origin)

Inferior ramus of pubis and ischial tuberosity of ischium.

Adductor magnus (insertion)

Adductor part: adductor tubercle of femur. Hamstring part: linea aspera of femur.

Obturator externus (action)

Laterally rotates thigh.

Obturator externus (origin)

Anterior surface of obturator membrane.

Obturator externus (insertion)

Trochanteric fossa of femur.

Tensor fasciae latae (action)

Abducts, medially rotates, and flexes thigh; flexes and laterally rotates knee once knee is past 30°.

Tensor fasciae latae (origin)

Iliac crest and lateral surface of anterior superior iliac spine.

Tensor fasciae latae (insertion)

Gerdy's tubercle via the iliotibial tract (IT band).

Gluteus maximus (action)

Extends and laterally rotates thigh.