Anatomy Lab Exercise 10 Week 4 Content

How many bones make up the appendicular skeleton

126 Bones

What components make up the appendicular skeleton

• Appendages

• Pectoral girdle

• Pelvic girdle

Pectoral girdle

• Consists of two bones

  • The anterior clavicle and posterior scapula

The clavicle articulates with the axial skeleton via __.

The sternum

The scapula __ articulate with the axial skeleton.

Does not

Why is the shoulder girdle exceptionally light and mobile

• The sternoclavicular joints are the only site of attachment of the shoulder girdles to the axial skeleton.

• The relative looseness of the scapular attachment allows it to slide back and forth against the thorax with muscular activity.

• The glenoid cavity is shallow and does little to stabilize the shoulder joint.

Limitations of a mobile shoulder girdle

• The humerus is very susceptible to dislocation

• Fracture of the clavicle disables the entire upper limb because it acts as a brace to hold the arm away from the top of the thoracic cage

Humerus

• Proximally rounded head fits into the shallow glenoid cavity of the scapula.

• Separated from the shaft by the anatomical and surgical neck

• The surgical neck is more constricted

How many bones make up the carpus

8 Bones

Carpals

Arranged in two irregular rows of four bones each

Which bones make up the proximal row of carpals

• Scaphoid

• Lunate

• Triquetrum

• Pisiform

Which bones make up the distal row of carpals

• Trapezium

• Trapezoid

• Capitate

• Hamate

Metacarpals

Number one through five from the thumb side

The bases of the metacarpals articulate with the __. The more bulbous heads articulate with the _ distally.

Carpals and phalanges

How many bones make up the phalanges

14 bones

How many phalanges per finger

3 bones except for the thumb which has two

Humerus greater tubercle

Large lateral prominence; site of the attachment of rotator cuff muscles

Humerus lesser tubercle

Small medial prominence; site of attachment for rotator cuff muscles

Humerus intertubercular sulcus

A groove separating the greater and lesser tubercles; the tendon of the biceps brachii lies in this groove.

Humerus deltoid tuberosity

A roughened area about midway down the shaft of the lateral humerus; site of attachment for the deltoid muscle

Humerus radial fossa

Small lateral depression; receives the head of the radius when the forearm is flexed.

Humerus coronoid fossa

Small medial anterior depression; receives the coronoid process of the ulna when the forearm is flexed

Humerus capitulum

A rounded lateral condyle that articulates with the radius

Humerus trochlea

A flared medial condyle that articulates with the radius

Humerus trochlea

A flared medial condyle that articulates with the ulna

Humerus lateral epicondyle

Rough condyle proximal to the trochlea

Humerus radial groove

Small posterior groove, marks the course of the radial nerve

Humerus olecranon fossa

Large distal posterior depression that accommodates the olecranon of the ulna

Radius head

The proximal end of the radius that forms part of the proximal radioulnar joint and articulates with the capitulum of the humerus

Radius radial tuberosity

Medial prominence just below the head of the radius; site of attachment of the biceps brachii

Radius radial styloid process

Distal prominence; site of attachment for ligaments that travel to the wrist

Radius ulnar notch

Small distal depression that accommodates the head of the ulna, forming the distal radioulnar joint.

Ulna olecranon

Prominent process on the proximal ulna; articulates with the olecranon fossa of the humerus when the forearm is extended

Ulna trochlear notch

Deep notch that separates the olecranon and the coronoid process; articulates with the trochlea of the humerus

Ulna coronoid process

Shaped like a point on a crown; articulates with the trochlea of the humerus

Ulna radial notch

Small proximal lateral notch that articulates with the head of the radius; forms part of the proximal radioulnar joint

Ulna head

Slim distal end of the ulna; forms part of the distal radioulnar joint

Ulnar styloid process

Distal pointed projection; located medial to the head of the ulna

How many bones form the pelvic or hip girdle

Two bones (ossa coxae)

Pelvis

Deep structure formed by the hip bones, sacrum, and coccyx

How do the bones of the pelvic girdle differ from the pectoral girdle

• Pelvic bones are heavy and massive

• The sockets for the femurs are deep and heavily reinforced by the ligaments to ensure stability

• Weight bearing is more important than mobility

Which bones make up the hip bones

1. Ilium

2. Ischium

3. Pubis

The socket formed by the ilium, ischium, and pubis is called _

Acetabulum

Obturator

A bar of bone formed by the rami of the pubis and ischium

How are the male and female pelvis different

The female pelvis is wider, shallower, lighter, and rounder

Pelvic brim

A continuous oval ridge of bone that runs along the pubic symphysis, pubic crests, arcuate lines, sacral alae, and sacral promontory

False pelvis

• Portion of the pelvis superior to the pelvic brim

• Bound by the alae of the ilia laterally and the sacral promontory and lumbar vertebrae posteriorly.

• Supports the abdominal viscera without impeding childbirth

True pelvis

• The inferior region of the pelvic brim that is almost entirely surrounded by bone

Pelvic inlet

• Opening delineated by the pelvic brim

• Widest dimension of the pelvic inlet from left to right

Pelvic outlet

• Inferior margin of the true pelvis

• largest outlet anterior to posterior

Ilium iliac crest

Thick superior margin of bone

Ilium anterior superior iliac spine

The blunt anterior end of the iliac crest

Ilium posterior iliac spine

The sharp posterior end of the iliac crest

Ilium anterior inferior iliac spine

Small projection located located below the anterior superior iliac spine

Ilium posterior inferior iliac spine

Small projection located just below the posterior superior iliac spine

Ilium greater sciatic notch

Deep notch located inferior to the posterior inferior iliac spine, allows sciatic nerve to enter the thigh

Ilium iliac fossa

Shallow depression below the iliac crest; forms the internal surface of the ilium

Ilium auricular surface

Rough medial surface that articulates with the auricular surface of the sacrum, forming the sacroiliac joint

Ilium arcuate line

A ridge of bone that runs inferiorly and anteriorly from the auricular surface

Ischium ischial tuberosity

Rough projection that receives the weight of our body when we are sitting

Ischium ischial spine

Located superior to the ischial tuberosity and projects medially into the pelvic cavity

Ischium lesser sciatic notch

A small notch located inferior to the ischial spine

Ischium ischial ramus

Narrow portion of the bone that articulates with the pubis

Pubis superior pubic ramus

Superior extension of the body of the pubis

Pubis inferior pubic ramus

Inferior extension of the body of the pubis; articulates with the ischium

Pubis pubic crest

Thick anterior border

Pubis pubic tubercle

Lateral end of the pubic crest; lateral attachment for the inguinal ligament

Pubis articular surface

Surface of each pubis combines with the fibrocartilage to form the pubic symphysis

Femur

• Heaviest and strongest bone in the body

• Articulates with the hip bone via the deep secure socket of the acetabulum

Patella

Triangular sesamoid bone enclosed in the quad tendon that secures it to the anterior femur and tibia

Femur fovea capitis

A small pit in the head of the femur for the attachment of a short ligament that runs to the acetabulum

Femur neck

Weakest part of the femur, the usual fracture site of a broken hip

Femur greater trochanter

Large lateral projection; serves as a site for muscle attachment on the proximal femur

Femur lesser trochanter

Large posteromedial projection; serves as site for muscle attachment on the proximal femur

Femur intertrochanteric line

Thin ridge of bone that connects the two trochanters anteriorly

Femur intertrochanteric crest

Prominent ridge of bone that connects the two trochanters posteriorly

Femur gluteal tuberosity

Thin ridge of bone located posteriorly; serves as a site for muscle attachment on the proximal femur

Femur linea aspera

long vertical ridge of bone on the posterior shaft of the femur

Femur medial and lateral supracondylar lines

Two lines that diverge from the linea aspera and travel to their respective condyles

Femur medial and lateral condyles

Distal wheel shaped projections that articulate with the tibia, each condyle has a corresponding epicondyle

Femur intercondylar

Deep depression located between the condyles and beneath the popliteal surface

Femur adductor tubercle

A small bump on the superior portion of the medial epicondyle; attachment site for the large adductor magnus muscle

Femur patellar surface

Smooth distal anterior surface between the condyles; articulates with the patella

Tibia lateral condyle

Slightly concave surface that articulates with the lateral condyle of the femur; the inferior region of this condyle articulates with the fibula to form the superior tibiofibular joint

Tibia medial condyle

Slightly concave surface that articulates with the medial condyle of the femur

Tibia intercondylar eminence

Irregular projection located between the two condyles

Tibial tuberosity

Roughened anterior surface; site of patellar ligament attachment

Tibia anterior border

Sharp ridge of bone easily palpated because it is close to the surface

Tibia medial malleolus

Forms the medial bulge of the ankle

Tibia inferior articular surface

Distal surface of the tibia that articulates with the talus

Tibia fibular notch

Smooth lateral surface that articulates with the fibula to form the inferior tibiofibular joint

Fibula head

Proximal end of the fibula that articulates with the tibia to form the superior tibiofibular joint

Fibula lateral malleolus

Forms the lateral bulge of the ankle and articulates with the talus

Tibia

The larger, medial, weight-bearing bone of the leg

Fibula

Lies parallel to the tibia; takes no part in forming the knee joint.

How many tarsals are there

7 Bones

How many metatarsals are there

5 Bones

How many phalanges are in the feet

14 bones

Calcaneus and talus

The largest tarsals that hold the majority of the body weight