Human Anatomy and Physiology: Skeletal System

Upper Limb Anatomy

• Humerus: Long bone of the upper arm; features include:
  • Head: Enlarged end articulating with the scapula's glenoid cavity.
  • Olecranon fossa: Depression on the posterior side, accommodating the olecranon process.
  • Olecranon process: Elbow's bony point that slides in the olecranon fossa during arm extension.
• Radius: Thumb-side bone; features:
  • Proximal head: Disc-shaped, rotates on the humerus.
  • Radial tuberosity: Muscle attachment point for biceps.
• Ulna: Longer bone of the lower arm, located opposite the radius.

Lower Limb Anatomy

• Femur: Longest and strongest bone; articulates with the pelvis at the acetabulum forming a ball-and-socket joint.
• Patella: Triangular sesamoid bone; ossifies between ages three and six, embedded in knee tendon.
• Tibia: Weight-bearing shinbone; articulates with the femur and carries body weight.
• Fibula: Slender bone alongside the tibia, does not bear weight but stabilizes the ankle.
• Foot and Ankle Bones:
  • Phalanges: Toe bones; hallux has 2 bones, other toes have 3.
  • Metatarsals: Five bones numbered I-V, forming the foot's middle portion.
  • Tarsals: Include seven bones, with talus and calcaneus being key components for ankle movement and weight support.

Joint Anatomy

• Knee Joint: A synovial joint involving femur, tibia, and patella; supported by five ligaments:
  • Collateral ligaments: Prevent side-to-side movement.
  • Cruciate ligaments: Cross to stabilize forward and backward movement.
  • Patellar ligament: Attaches the patella to the tibia, functioning as both tendon and ligament.

Bone Development

• Mineral Deposition: Osteoblasts synthesize bone matrix, vital for bone formation and collagen fiber development.
• Intramembranous Ossification: Forms flat bones, e.g., skull.
• Endochondral Ossification: Forms long bones through cartilage models; primary ossification located in the diaphysis.

Fracture Types

• Complete Fracture: Bone in two or more pieces.
• Displaced Fracture: Bone misalignment.
• Non-Displaced Fracture: Bone remains aligned.
• Hairline Fracture: Crack in the bone.
• Greenstick Fracture: Partial break, one side broken.
• Spiral Fracture: Spiral break pattern.
• Compression Fracture: Common in vertebrae due to compression.

Diagnostic Tools

• DEXA Scan: Measures bone density using low-dose radiation.
• X-ray: Visualizes dense structures, useful for diagnosing bone disorders.

Skeletal Conditions

• Osteoporosis: "Porous bones"; severe loss of density, affecting cancellous bone.
  • Causes include vitamin D deficiency and diminished hormone levels due to aging.
• Mastoiditis: Infection of the mastoid bone, often stemming from untreated ear infections; treated with antibiotics, sometimes requiring surgery.
• Bursitis: Inflammation of the bursa causing pain, common in joints like the knee and shoulder.
• Arthritis: Inflammation of joints, with over 100 types; osteoarthritis and rheumatoid arthritis are prominent forms.
• Osteogenesis Imperfecta: Congenital defect leading to brittle bones from collagen deficiency.
• Rickets: Childhood disorder from inadequate mineral deposition, resulting in soft bones.

This quiz covers the anatomy and physiology of the skeletal system, focusing on the appendicular skeleton, particularly the upper limb. Participants will explore the structure and features of the humerus, radius, ulna, and carpal bones. Test your knowledge about bone markings and their significance in human anatomy.