Anatomy: Bone and Bone Trabecular Bone Essay

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宁波大学 早安 你好 我是你的老师 我叫Mike mike.hehir@btinternet.com Human Anatomy
Introduction

What is anatomy?
• Tissues are composed of cells • Tissue
– – – – – – – – – – – – – Epithelial Connective Muscle Nerves Locomotor Alimentary Respiratory Urinary Reproductive Circulation Sense Organs Nervous Endocrine

• Systems

Classification: types of Anatomy:
• Gross • Microscopic • Developmental
– (embryology)

• • • • • •

Radiographic Clinical Surface Sectional Systematic Regional

Anatomical Position
Erect body Face and toes forward Hands by the side, Palms forward Right and left of Subject, not of Observer Anterior = Ventral means towards the front Posterior = Dorsal means towards the back Superior = Cranial means upper part or direction towards the head • Inferior = caudal means lower part or towards the feet • • • • • • •

Anatomical Position
• Medial means nearer to the median plane, a line that divides the body between the eyes in 2 equal parts • Lateral means nearer the sides
– N.B Little finger is MEDIAL to the thumb but the little toe is LATERAL to the big toe

Medial and lateral Rotation Internal nearer centre of a cavity External farther from a cavity Superficial near the surface of the body or organ Deep deep in side the body or organ Proximal means nearer the central attachment of a limb or cranial end of a tubular organ like the gut or Aorta • Distal means further away from the attatchent or cranial end of a limb or other organ • • • • • •

Anatomical Position

Anatomical planes
• • • • Median: two equal halves between the eyes Sagittal: like Median but off centre Coronal: at right angles to Median Horizontal or Transverse

• Each of these planes are at right angles to each other (Except for Median and Sagittal as they are parallel)

Osteology – Bones!
• Skeleton provides a framework to support the body • 206 distinct bones in the adult skeleton • Skull and bones of the Trunk are the Axial skeleton • Bones of the limbs are the Appendicular Skeleton

Long Bones
• Arms:
– Humerus, Radius and Ulna

• Legs:
– Femur, Tibia and Fibula

• Long Bones have:
– A Body or Shaft:
– Tubular shape, Thick compact bone outside, – Medullary cavity containing some Bone marrow

– Expanded ends – spongy or Cancellous bone
– Epiphises in children Cartilage plates where the bone grows, when it closes growth ceases and it leaves an epiphiseal line

– Articular surfaces
– To contribute to joints

Short, Flat and Irregular Bones
• • Short: – Cancellous bone with a thin crust of compact bone – Ankle and wrist Flat: – Protective bones, Thick outer plate and thin inner – Occipital, Frontal and parietal bones of the skull – Spongy middle ‘Diploe’. Can expand and fill with air (sinuses) – Ribs, Sternum, Scapulae – Ileum, Ischium and Pubis of pelvic bone or ‘hip’ bone Irregular: – Various shapes, in Face and Spinal Column Thin outer compact and inside spongy layer – Skull: Sphenoid, Temporal, Zygomatic, ethmoid, maxilla, mandible – Vertebrae Sesamoid: – Bones inside tendons – Patella or kneecap and some small ones in the hands and feet





Cortical Bone

Trabecular Bone
• Histology similar to Cortical Bone, • High ratio of surface to volume • Contains marrow

Bone marks and features
• • • • • • Tuberosity Tubercle Spine Ridge, Crest or Line Depressions, fossa, Sulcus, fissure, notch Foramen, Canal

Osteoblasts and Osteoclasts

What is the structure of bone
• Bone Matrix: Ca (PO ) with Calcium Hydroxide Hydroxyapatite crystals forming tubes • Osteon or Haversian system • Osteocytes line the canal, making Collagen, and Matrix. Proteoglycans support collagen growth. • Matrix is thick and hard with linear stress lines in compact bone, and thin in spongy bone. • Periosteum an thin outer layer containing nerves and blood vessels that penetrate and supply the bone
3 4 2

– Note effect of removing mineral bone in organic solvents or burning it to remove the protein…