Detail into Musculoskeletal system

Page 1

PERIOSTEUM

* Outer layer surrounding bone except at articular surfaces

A thicker layer at the shaft, proximal and distal areas of the bone

* It provides bone nourishment because it's vascularised

* Has 2 layers

FIBROUS - lots of collagen and elastic fibers

CELLULAR - deeper than the fibrous layer and more vascularised

* Has osteoprogenitor cells that help when bone is fractured

* Connected to bone via Sharpey's Fibres --> strong collagenous fibers. Allows bone to get the periosteum's blood supply and access it's osteoprogenitor cells.

Page 2

CONNECTIVE TISSUE COVERINGS OF THE MUSCLE

Epimysium

Dense connective tissue that covers the entire muscle organ

Perimysium

Thicker connective tissue that surrounds the fascicles (a bundle of muscle fibers/cells)

Endomysium

Connective tissue that surrounds the individual muscle fibers

Page 3

MUSCLE ATTACHMENTS

Fascia

fibrous membraneous covering that separates the muscles

Aponeurosis

flat, tendinous sheet that joins one muscle to another OR to bone

Tendons

strong fibrous band of tissue that extends from a muscle, attaching it to the bone by becoming continuous with the periosteum of the bone. poorly vascularised

Belly

the fleshy midsection of muscle. contractile portion. Highly vascularised

Origin

the point of attachment of a muscle to a bone that is fixed and doesn't move during contractions. usually the proximal end

Insertion

the point of attachment of a muscle to a bone it moves. usually distal end

Page 4

SYNOVIAL JOINT

Articular cartilage

hyaline cartilage that lines the articulating surfaces of the bone. degenerates with age. reduces friction and withstands compression

Fibrous Capsule

outermost layer that surrounds the entire joint cavity and is continuous with the periosteum of the bone. dense connective tissue that's reinforced by muscle attachment and ligaments. contains intracapsular structures

Synovial Membrane

simple squamous mesothelial cells that line the inside of the fibrous capsule. has a rich vascular supply. doesn't line the articular/hyaline cartilage. secretes synovial fluid.

Synovial fluid

functions as nutrients for articular cartilage, shock absorption, and lubricant for articular surfaces. Synovial Effusion is a condition where a piece of the synovial membrane comes off and is trapped within the cavity = irritation and swelling = blood and pus