Appendicular Skeleton and Joints: Study Guide for Anatomy & Physiology

Appendicular Skeleton

Overview of the Appendicular Skeleton

The appendicular skeleton consists of the bones of the limbs and the girdles that attach them to the axial skeleton. It is essential for movement and manipulation of the environment.

• Pectoral Girdle: Composed of the scapula and clavicle, connecting the upper limb to the trunk.

• Upper Extremities: Includes the humerus, radius, ulna, carpals, metacarpals, and phalanges.

• Pelvic Girdle: Formed by the coxal bones (hip bones), connecting the lower limb to the trunk.

• Lower Extremities: Composed of the femur, patella, tibia, fibula, tarsals, metatarsals, and phalanges.

Pectoral Girdle

• Scapula (Shoulder Blade):

  • Anterior view: Acromion process, glenoid fossa, coracoid process, superior border, superior angle, subscapular fossa, lateral border, medial border, inferior angle.

  • Posterior view: Supraspinous fossa, spine of the scapula, infraspinous fossa.

• Clavicle (Collar Bone): Sternal end, acromial end.

Upper Extremities

• Humerus (Arm Bone):

  • Proximal end: Head, anatomical neck, surgical neck, greater tubercle, lesser tubercle, intertubercular sulcus.

  • Mid-shaft: Deltoid tuberosity.

  • Distal end: Medial/lateral supracondylar ridge, medial/lateral epicondyle, coronoid fossa, olecranon fossa, trochlea, capitulum.

• Ulna (Medial Forearm Bone):

  • Proximal end: Olecranon, trochlear notch, coronoid process, radial notch of ulna.

  • Distal end: Head, styloid process.

• Radius (Lateral Forearm Bone):

  • Proximal end: Head, neck, radial tuberosity.

  • Distal end: Styloid process.

• Carpals (Wrist Bones):

  • Proximal row (lateral to medial): Scaphoid, lunate, triquetrum, pisiform.

  • Distal row (lateral to medial): Trapezium, trapezoid, capitate, hamate.

• Metacarpals (Palm Bones): Numbered 1-5 (thumb to little finger).

• Phalanges (Bones of the Fingers): Proximal (5), middle (4; not found on digit 1), distal (5).

Pelvic Girdle

• Coxal (Hip) Bone:

  • Ilium: Auricular surface, iliac crest, iliac fossa, anterior superior/inferior iliac spine (ASIS/AIIS), posterior superior/inferior iliac spine (PSIS/PIIS), greater sciatic notch.

  • Pubis: Superior/inferior pubic ramus.

  • Ischium: Ischial spine, lesser sciatic notch, ischial tuberosity.

  • Other features: Acetabulum, obturator foramen, pelvic brim, subpubic angle (female is broader), pubic symphysis.

Lower Extremities

• Femur (Thigh Bone):

  • Proximal end: Head, neck, greater/lesser trochanter, intertrochanteric crest/line.

  • Shaft: Gluteal tuberosity, linea aspera.

  • Distal end: Patellar groove, lateral/medial epicondyle, lateral/medial condyle, intercondylar fossa.

• Patella (Knee Cap): Anterior surface.

• Tibia (Medial Leg Bone):

  • Proximal end: Intercondylar eminence, lateral/medial condyle, tibial tuberosity.

  • Shaft: Anterior crest.

  • Distal end: Medial malleolus.

• Fibula (Lateral Leg Bone):

  • Proximal end: Head.

  • Distal end: Lateral malleolus.

• Tarsals (Foot Bones): Talus, calcaneus, navicular, medial/intermediate/lateral cuneiform, cuboid.

• Metatarsals: Numbered 1-5.

• Phalanges (Bones of the Toes): Proximal (5), middle (4; not found on digit 1), distal (5).

Anatomical Models

• Full skeleton

• Loose bones of the appendicular skeleton

In-Lab Assignments/Experiments

• Identify all bones of the appendicular skeleton

• Identify structures associated with each bone

• Identify bones pulled from the skeleton and their orientation

Classification of Joints

Overview of Joint Types

Joints, or articulations, are connections between bones that allow for movement and provide mechanical support. They are classified based on their structure and the type of tissue that connects the bones.

• Fibrous Joints: Bones held together by dense connective tissue; little to no movement.

  • Suture: Cranial bones

  • Gomphosis: Teeth and mandible

  • Syndesmosis: Distal ends of fibula and tibia, ankle

• Cartilaginous Joints: Bones held together by cartilage.

  • Synchondrosis: Hyaline cartilage (e.g., epiphyseal plate)

  • Symphysis: Fibrocartilage (e.g., pubic symphysis)

• Synovial Joints: Freely movable joints with a synovial cavity.

  • Gliding: Carpal joints

  • Hinge: Elbow

  • Pivot: Proximal ulna and radius

  • Condyloid: Metacarpal and phalangeal joints

  • Saddle: Metacarpal I and trapezium (thumb joint)

  • Ball-and-socket: Shoulder and hip

Major Joints of the Body

• Shoulder (Glenohumeral Joint):

  • Coracoacromial ligament

  • Coracoclavicular ligament

  • Acromioclavicular ligament

  • Superior/inferior glenohumeral ligament

• Hip (Acetabulofemoral Joint):

  • Iliofemoral ligament

  • Ischiofemoral ligament

  • Pubofemoral ligament

• Knee (Tibiofemoral Joint):

  • Lateral (fibular) collateral ligament

  • Medial (tibial) collateral ligament

  • Quadriceps femoris tendon

  • Patellar ligament

  • Anterior cruciate ligament (ACL)

  • Posterior cruciate ligament (PCL)

  • Medial meniscus

  • Lateral meniscus

• Note: The "unhappy triad" refers to the structures most commonly injured in lateral impact sports injuries: ACL, MCL, and medial meniscus.

In-Lab Assignments/Experiments (Joints)

• Identify various types of joints

• Identify various ligaments associated with the joints

Summary Table: Major Bones of the Appendicular Skeleton

Region	Main Bones	Key Features
Pectoral Girdle	Scapula, Clavicle	Acromion, glenoid fossa, spine, sternal/acromial ends
Upper Extremity	Humerus, Radius, Ulna, Carpals, Metacarpals, Phalanges	Head, tubercles, epicondyles, styloid processes, carpal bones
Pelvic Girdle	Ilium, Ischium, Pubis	Crest, spines, notches, acetabulum, obturator foramen
Lower Extremity	Femur, Patella, Tibia, Fibula, Tarsals, Metatarsals, Phalanges	Head, neck, trochanters, condyles, malleoli, tarsal bones

Summary Table: Classification of Joints

Type	Examples	Movement
Fibrous	Suture, gomphosis, syndesmosis	Immovable or slightly movable
Cartilaginous	Synchondrosis, symphysis	Slightly movable
Synovial	Gliding, hinge, pivot, condyloid, saddle, ball-and-socket	Freely movable

Key Terms and Definitions

• Appendicular Skeleton: The portion of the skeleton that includes the limbs and girdles.

• Girdle: A set of bones that attach the limbs to the axial skeleton (pectoral and pelvic).

• Phalanges: Bones of the fingers and toes.

• Joint (Articulation): The site where two or more bones meet.

• Ligament: A band of connective tissue that connects bones at a joint.

• Meniscus: A fibrocartilaginous structure in the knee that improves joint stability.

Additional info:

• Students should be able to identify bones and their features on anatomical models and skeletons.

• Understanding joint classification is essential for recognizing movement capabilities and injury mechanisms.