Anatomical Spaces And Bones Flashcards
What is an anatomical space
Also known as ‘spatium’
A continuous area of anatomy or expanse that is free, available or unoccupied
Divided into 2 categories:
True anatomical spaces-e.g. oral cavity
Potential spaces- do not exist as part of normal anatomy, created as result of pathologies
Anatomical spaces can be sites of collections of: gases, blood, pus, oedema, fat deposits, cysts, tissues or growths etc
Can be invaded by many pathologies, insidious growths can grow without being detected
Coelomic cavity
The 2 largest anatomical spaces of the body are created from an embryonic fluid filled cavity lined with mesothelium= the coelomic cavity
Visceral organs form within the coelom and are able to move, grow and develop independently of the body wall
What is bone
Rigid tissue of the body that forms the skeleton
Consisting of cells embedded in an abundant hard intercellular material
Constituted from connective tissue made from: cells, fibres, matrix
Occurs in 2 forms: compact bone (solid mass of dense connective tissue) and cancellous bone (branching network of trabeculated dense connective tissue)
What are the types of bones
Flat
Sesamoid
Irregular
Long
Short
What is Periosteum
A dense layer of vascular connective tissue enveloping the bones except at surfaces of joints
Generates stem cells of bone known as osteoblasts, osteoclasts and osteocytes
Has a rich blood supply that nourishes bone
Maintains bone in a healthy state
Repairs bone in case of fractures
It has rich innervation from sensory nerves of the somatic nervous system for pain sensation from bone
Flat bones
Function is to protect internal organs such as heart, brain, pelvic organs. Provide a connection point for your muscles
Tissue layers:
-composed of a layer of spongy bone (diploe) between 2 thin layers of compact bone. Trilaminar
Spongy bone= trabecular bone
Considered to be strong and protective
Also used routinely in tapping bone marrow
Long bones
Longer than they are wide
Has a shaft and 2 ends
Thick outside layer of compact bone and inner medullary cavity (marrow cavity) containing red or yellow bone marrow
Endosteum- thin vascular membrane of connective tissue that lines inner surface of bony tissue that forms the medullary cavity of long bones
Periosteum lines long bones, maintenance, grow and repair, blood and nerve supply to bone
Function of long bones: strength (hard and dense), structure and mobility
Gross structure of periosteum (or endosteum)
Consists 2 layers of tissue
Fibrous layer (outer layer)- collagenous, fibroblasts make collagen and extracellualr matrix
Cellular layer (inner layer)
Collagen fibres of the periosteum are continuous with those of bone, adjacent joint capsule, tendon and ligaments
Soft tissues or membranous lining of cartilage
Cartilage is also covered in soft tissue linings that are similar and analogous to those of bone
Soft tissue that lines cartilage is perichondrium
Perichondrium supports its parent cartilage in much the same way as periosteum supports its parent bone, supply’s blood which distributes nutrients and oxygen necessary to strengthen and nourish cartilage, growth and repair of cartilage
Gross structure of perichondrium
Consists of 2 layers of tissues
Fibrous layer (or outer layer)
-Maintained by fibroblasts- fibrocytes, collagenous
Cellular layer (inner layer)
-chondrogenic layer, produces cartilage
-chondroblasts -chondrocytes
Bony spaces
Surfaces of bones onto which muscles, tendons, ligaments and soft tissues attach
What are fossae
A depression or hollow usually in bone
E.g. hypophyseal fossa (depression in the sphenoid bone)
What are paranasal sinuses
Series of hollow spaces/ cavities within bones of head
Paired and symmetrical
Have following characteristics:
-open into nasal cavity
- are lined by 2 layers of soft tissues:
Periosteum
Secretory epithelium- pseudostratified columnar epithelium, a thin membrane that’s continuous and same as that lining nasal cavity, with goblet cells (secret mucus, found within epithelium of respiratory system)
Neuronal innervation of epithelium lining of paranasal sinuses
Somatic sensory innervation:
-derived from the sensory division of the Trigeminal nerve- ophthalmic branch and maxillary
-sensations are somatic and therefore are consciously aware of them
-pain, temp, irritation etc
Autonomic parasympathetic innervation:
-derived from the efferent division of the autonomic nervous system
-increase secretions from nasal cavity and paranasal sinuses
-commonly derived from the autonomic division of CNVII- greater petrosal branch of CNVII
Generic design of muscles of body wall
Consists essentially of 3 layers muscle
Muscles encircle cavity of body
Muscle fibres lie in different slopes of obliquity
The intermediate layer is reinforced with bony condensation to a cranio-caudal extent
