Bones Articulations Flashcards

Cranial and Facial Bones

• Cranial bones protect the brain and include the frontal, paired parietals, paired temporals, occipital, sphenoid, and ethmoid.
• The frontal bone forms the roof of the eye orbit.
• The occipital bone articulates with cervical vertebrae, supporting the head.
• The sphenoid bone articulates with all cranial bones, forming the posterior lateral and medial sides of the orbit.
• The ethmoid bone contributes to the nasal passages and the medial portion of the orbit.
• Facial bones consist of paired nasal, paired maxillae, paired zygomatics, mandible, and paired lacrimals.

Fontanels and Thorax Structure

• Fontanels are incomplete ossification areas that allow movement for easier delivery during childbirth and accommodate brain growth.
• The thorax includes vertebrae, ribs, and the sternum, providing structural support.

Types of Thoracic Vertebrae

• Cervical vertebrae (7 total) support and move the head; unique with transverse foramen for blood vessels and nerves.
• Thoracic vertebrae (12 total) support the ribs; identified by articular facets on transverse processes.
• Lumbar vertebrae (5 total) are larger and support greater body weight; characterized by blunt processes.
• Sacral vertebrae (5 total) are fused and articulate with the pelvic girdle.
• The coccyx is the remnant of the tail, fused and located at the end of the vertebral column.

Ribs and Sternum

• Ribs articulate with thoracic vertebrae through hyaline cartilage.
• True ribs (1-7) articulate directly with the sternum via cartilage.
• False ribs (8-12) attach indirectly to the sternum through cartilage.
• Floating ribs (11-12) do not articulate with the sternum.
• The sternum articulates with ribs 1-10, serving as a central anchor.

Appendicular Skeleton

• The appendicular skeleton includes the pectoral girdle, upper appendages, and pelvic girdle.
• The pectoral girdle (shoulders) consists of two bones (clavicle and scapula) that allow for free movement but are less stable.
• The clavicle (collarbone) articulates with the sternum and acromion of the scapula.
• The scapula (shoulder blade) is a flat bone that serves as an attachment site for shoulder muscles.

Upper and Lower Appendages

• Upper appendages consist of the arm bone (humerus), forearm bones, wrist, palms, and fingers.
• Humerus articulates proximally with the scapula and distally with radius and ulna.
• The forearm contains the radius (lateral, near the thumb) and ulna (medial, near the body).
• The pelvic girdle is larger and stronger than the pectoral girdle, comprised of coxal bones (ilium, pubis, ischium) that articulate at the acetabulum.

Gender Differences in Pelvic Structure

• Key differences in pelvic structure include the pubic arch and pelvic inlet being wider in females, along with a greater sciatic notch and overall wider shape.

Bones of the Lower Appendages

• The lower appendages consist of the thigh (femur), leg (tibia and fibula), tarsals, metatarsals, and phalanges.
• The femur is the largest and heaviest bone, articulating with the coxal bone and tibia at the knee.
• The fibula is a smaller bone that does not bear weight, while the tibia is larger and articulates with the femur and the talus.

Joint Articulations

• Synarthrotic articulations involve no movement.
• Amphiarthrotic articulations allow for some movement.
• Diarthrotic articulations are freely movable.
• Fibrous articulations connect bones with short fibers, allowing for limited movement.

Explore the essential bones of the human skull with these flashcards. Each card provides definitions and articulations of the cranial bones, including the frontal, occipital, and sphenoid bones. Enhance your understanding of cranial anatomy and its role in protecting the brain.