lecture 9 with 10

Bone Healing Process

• Breakages in Bone

  • Bones have a rich blood supply that is disrupted when fractures occur.

  • Fibrocartilage Formation: After fracture, fibrocartilage is utilized to bridge the gap where blood vessels were damaged, aiding in the healing process.

Osteoporosis Factors

• Sex-Related Factors:

  • Women are 2-3 times more likely to develop osteoporosis than men due to hormonal differences.

  • Hormones protect skeletal health; their reduction increases vulnerability to bone mass loss.

• Age-Related Changes:

  • As individuals age, hormone levels and bone density can decrease, leading to a predisposition for conditions like scoliosis, kyphosis, and lordosis.

Scoliosis, Kyphosis, and Lordosis

• Scoliosis:

  • Characterized by a lateral curvature of the spine, often visible in thoracic and lumbar regions.

  • Causes: Rapid growth phases (e.g., during adolescence) can lead to imbalances in supportive structures like connective tissues.

• Kyphosis:

  • Known as hunchback; excessive curvature of the thoracic spine.

  • Often a result of wear and tear, osteoporosis, or poor posture.

  • Good posture is essential to prevent long-term spinal problems.

• Lordosis:

  • Swayback condition where the lumbar spine curves excessively inward.

  • Often due to poor posture and overloading of the spine.

Herniated Discs

• Intervertebral Discs:

  • Composed of fibrocartilage, providing stability between vertebrae.

  • Discs have an outer layer (annulus fibrosus) and a soft center (nucleus pulposus).

  • Herniation occurs when the disc bulges and compresses spinal nerves, causing pain and potential nerve damage.

• Symptoms:

  • Pain may radiate, and individuals may experience numbness or muscle weakness.

  • Treatment varies from conservative management to surgical intervention (e.g., laminectomy).

Vertebral Anatomy

• Vertebrae Types:

  • Cervical:

    • Characterized by transverse foramen; allow head motion.

  • Thoracic:

    • Hold ribs; spines can resemble a crown and are more robust due to muscle attachment.

  • Lumbar:

    • Larger bodies due to weight support; intervertebral discs are larger for shock absorption.

• Pelvis and Sacrum:

  • Sacrum consists of five fused vertebrae; unique in shape.

  • Coccyx varies between individuals, fused remnant of tail.

Ribs and Sternum

• Rib Structure:

  • Composed of both bony and cartilage components; ribs are categorized as either true or false ribs.

    • True Ribs: First 7 pairs; directly attach to the sternum.

    • False Ribs: Last 5 pairs; do not directly connect to the sternum (e.g., floating ribs).

• Sternum:

  • Composed of the manubrium, body, and xiphoid process; hyaline cartilage provides flexibility for breathing and protects internal organs.

  • Connection to the vertebrae forms a protective thoracic cage, allowing for expansion during respiration.