Anatomy

Chapter 5 – Skeletal System Part III

Appendicular Skeleton – 126 bones of limbs, pectoral and pelvic girdles.

Bones of shoulder (pectoral) girdle are light, exceptionally flexible, easily dislocated.

Clavicle or collarbone

Scapula or shoulder blades

Bones of upper arm and forearm

ForearmRight Humerus

Thirty separate bones compose the arm and forearm.

Bones of the handCarpals (8)Metacarpals (1-5)Phalanges (14)

The Pelvis

Right Coxal BoneComparison of Male

and Female Pelvis

Bones of the Right Thigh and Leg

Bones of Right FootThe foot is composed of tarsals, metatarsals, and phalanges. Supports our body weight and serves as a lever that allows us to propel our bodies forward when we walk or run.

Tarsals (7)Metatarsals (5) Phalanges (14)

Joints of the BodyFunctional classification:Synarthroses - immovable joints (sutures in the skull)Amphiarthroses - slightly moveable joints (carpals)Diarthroses - freely moveable joints (limbs)

Structural Classification:Fibrous Cartilaginous Synovial

General Structure of a Synovial Joint

Types of Synovial Joints

Plane joint – wrist

Hinge joint – elbow

Pivot joint – elbow

Condyloid joint – knuckle

Saddle joint – thumb

Ball-and-socket joint – shoulder and hip

Inflammatory Disorders of the Joints

Homeostatic Imbalances:

Bursitis - “water on the knee”, inflammation of bursae or synovial membrane.

Arthritis – inflammation or degenerative disease that damage the joints.

Osteoarthritis - most common form of arthritis. “Wear-and-tear arthritis”.

Rheumatoid arthritis (RA) – onset 40 -50, more likely in women than men; autoimmune.

Gouty arthritis (gout) – uric acid crystals in the joints; more common in males; genetic.

Fetal SkeletonFontanels remain at birth to allow the brain to grow.

All areas are fully ossified by 2 yrs of age.

Adolescence ends when epiphyseal plates become fully ossified. Females at 18yrs and males at 21yrs.

Ossification centers in the skeleton of a 12 week fetus.