Week 1 Flashcards
What is fascia
Connective tissue containing varying amounts of fat that separate, support and interconnect organs and structures enable movement of one structure relative to another and allow the transit of vessels and nerves from one area to another
Superficial fascia
Subcutaneous connective tissue lying beneath and merging with the dermis . Attaches skin to rets of body
Categorised as fibrous fatty tissue and consists of various proportions of fibroblasts, aqueous matrix, elastin and collagen fibres and fat and immune cells
It allows movement of the skin over deeper areas of the body, acts as a conduit for vessels and nerves and serves as a metabolic reservoir
When is the only time the skin is separated from superficial fascia
When friction blisters of the skin develop, the inflammatory reaction of the friction burn leads to tissue fluid leaking out of the circulatory system and to separation of the skin from its superficial fascia. The skin over a blister soon dies because it is separated from its arterial supply
Deep fascia
The investing layer- most superficial, continuous throughout the body and wraps the body wall and limbs in a membrane of tough fibrous connective tissue that separates them from the skin and its attendant superficial fascia
Deep layer- inward continuations from the investing layer of deep fascia, in limbs deep fascia gives rise to intermuscular septa, interosseous membranes and periosteum. Lead to structural partitioning of a limb into distinct and separate muscular compartments
Muscular compartments
A typifying feature of muscles of a particular compartment is that they have common functions and share common innervation, arterial supply, venous drainage and lymphatics
If there’s a bleed or fluid accumulation within a muscular compartment of a limb this has the potential to escalate to a medical emergency within a short time this is the basis of compartment syndrome
Tendons
Dense regular connective tissue by consolidation of collagen fibres derived from the connective tissue envelopes that unsheathe the skeletal muscles
Act as sites of attachment of muscles to bone, bring about displacement of a bone about its joint
Axial skeleton
Skull, ribs and vertebrae
Appendicular skeleton
Upper limbs, lower limbs etc
Cartilage
Specialised type of hard connective tissue
Classified into hyaline, fibrous and elastic cartilage
Ligaments
Help to stabilise moveable joints
Dense regular connective tissue, tightly packed collagen bundles arranged in parallel so that they respond to mechanical stress from a single direction
Attach bones to bones
Bursae
Fluid filled sacs lined with a delicate smooth membrane, the synovial membrane, which is responsible for secreting synovial fluid
Found wherever tendons rub against bones, ligaments or other tendons and they allow skin to move easily over bony prominences
They’re completely sealed but in some places there’s communication between the bursal cavity and a synovial cavity
Fibrous joints
These occur when adjacent bones are connected by fibrous connective tissue. These are further divided into:
Sutures- which occur between most of the bones in the cranium
Syndesmoses- bones are more widely separated but are held together by either ligaments or wide sheets of connective tissue called interosseous membranes
In the jaws teeth are fit into the alveoli (bony sockets), the narrow fibrous joint between these and the roots of a tooth is called gomphosis
Cartilaginous joints
Bones are either connected through either hyaline cartilage or fibrocartilage
Primary cartilaginous joints (synchondroses) bones are united by hyaline cartilage, they occur primarily in bone growth, between the epiphysis and the diaphysis of long bones
Secondary cartilaginous joints (symphyses) are connected by fibrocartilage and tend to occur down the axis of the body they allow some restricted movement
Synovial joints
Allow for free movement between the bones and are the most common joints in the body
They consist of the articulating surfaces, a joint cavity between them and an articular capsule surrounding them
Articular cartilage comprises a special type of hyaline cartilage
Synovial joints are further classified in different groups depending on the shape of the adjacent bones and the angle they form
The shape will dictate the range of movement allowed
Agonist muscle
prime mover
The main muscle or muscle group directly responsible for a specific movement
Antagonist muscle
The muscle or muscle group that has the opposite action of a given agonist this helps the agonist perform its action
Synergists and fixators
Muscle/ muscle group which assists the agonist
These terms are sometimes used interchangeably but fixators have also a role in stabilising the joint whilst the agonist act
Isotonic contraction
Length of muscle changes, tension remains the same
The muscles can either lengthen( eccentric) or shorten (concentric)
Isometric contraction
The muscle is tense but maintains the same length
Why do ligaments and tendons heal slowly
They are poorly vascularised