Anatomy and Physiology Appendicular Skeleton

126 bones Pectoral girdle Pelvic girdle Arm and leg bones Hands and feet

Shoulder Girdle Two Bones –Clavicle or Collar Bone –Double Curve –Attaches to Manubrium of sternum and scapula –Braces the shoulder joint

Shoulder Girdle cont Scapula or Shoulder Blade Triangular “wings” Two important processes –Acromion connects to clavicle to form acomioclavicular joint (AC joint) –Coracoid points over the top of the shoulder for muscle attachment Suprascapular Notch for nerve passage “stinger” Glenoid cavity receives the head of the humerous Not directly attached to the axial skeleton

Shoulder Joint Attached only at the sternoclavicular joint Allows for much flexability Glenoid cavity is shallow and poorly reinforced by ligaments All the above lead to easy dislocation!!!!

Upper Arm Bone Humerus –Long bone –Proximal end= head- fits into glenoid cavity –Anitomical neck vs surgical neck –Trochlea and Capitulum Articulate with forearm

Lower Arm Two bones the Radius and Ulna Radius associated with the thumb (1 st phal) Ulna with the pinky (5 th phalange) Radius rotates over the ulna Radius articulates with the capitulum Ulna grabs the Trochlea with processes

The Hand SadScaphoid & LonelyLunate TravisTriquetrum Pushes Pisiform His Hamate CartCapitate ThroughTrapezoid Texas Trapezium

Pelvic Girdle Two Coxal Bones With the sacrun and coccyx = bony pelvis Bears the weight of a standing person –Must be strong and stable –Better than the shoulder joint!!!

Hip Bones Fusion of three bones –Ilium –Ischium –Pubis Ilium –Connects to sacrum (sacroiliac joint) –Big flaring alae (iliac crest)

Hip Bone Ischium –Inferior “Sit-down” bone –Ischial spine narrows the outlet of the pelvis –Sciatic Notch for nerves and blood vessels Pubis –Anterior bone –Forms obturator Formen with ischium –Two fuse at the symphysis pubis

Pelvis All three bones form acetabulum for thigh bone

Male Versus Female Female inlet and outlet (ischial spines) larger Female shallower and lighter Females alae flare more Female has smaller sacrum Smaller Pubic arc in females

Lower Limb Bones Thigh bone = Femur Heaviest and strongest bone in the body Slants medially –Seen more in females due to wider pelvis Lower leg = Tibia and Fibula Tibia is the shin bone Fibula smaller and lateral –only involved in ankle not knee

Femur Proximal end is the head (acetabulum) Greater and lesser trochanter & gluteal tuberosity for muscle attachment Largest and strongest bone in the body

Tibia/Fibula Joined proximally and distally at tibiofibular joint Connected by interosseous membrane Both have a malleolus Tibial tuberosity for patellar tendon

Foot Similar to hand Supports and moves 7 tarsal bones –Talus –Calcaneus –Navicular –Cuboid –3 Cuneiforms Metatarsals Phalanges

Foot Form 3 arches –Medial –Lateral –Transverse Flat feet caused by “fallen arches Plantar fasciitis

Joints Called articulations All bones but the hyoid join at least one other bone Allow for flexibility Classified by structure and function

Functional classification Synarthroses –Immoveable joints –Axial skeleton Amphiarthroses –Semi-moveable joints –Axial skeleton Diarthroses –Freely moveable –limbs

Structural Classification Fibrous –Usually immoveable Cartilagenous –Semi-moveable usually Synovial –Freely moveable Based on the tissue separating the bones

Fibrous Joints Skull sutures Also the distal ends of the tib/fib

Cartilaginous Joints One ends are joined by cartilage –Causes them to be amphiarthrotic Symphysis pubis Intervertebral Joints –Fibrous cartilage Rib and sternum joints are synarthrotic

Cartilaginous joints

Synovial Joints Articulating bones separated by a joint cavity Cavity filled with synovial fluid All of the limb joints 4 distinguishing features

Synovial joints 1.Articular cartilage 2.Fibrous capsule lined with synovial membrane 3.Joint cavity filled with fluid 4.Ligaments to stabilize the joint The often have bursae and tendon sheaths associated –May become inflammed causing pain/swelling

Types of Synovial Joints Based on shape of bones articulating 1.Plane joint –Flat short bones –No rotation ex: intercarpal joints

Hinge Joint 2. Hinge joint –Uniaxial or movement in one plane only –Ulna of the elbow grabs the humerus

Pivot Joint 3.Pivot Joint Round end of one into a ring on another Also uniaxial (rotation around long axis) Proximal radioulnar joint

Condyloid Joint 4. Condyloid Joint Round end fits into concave structure Biaxial (no rotation) Between the proximal phalange and metacarpal

Saddle Joint 5.Saddle joint Much like the condyloid just slight shape difference Biaxial

Ball and Socket Joint 6.Ball and socket joint Round end (head) of one bone fits into round socket Multiaxial including rotation Hip and shoulder