Myology

Myology

1. Functions of Skeletal

   • Movement
   • Heat Production
   • Maintain Posture

2. Types Of Muscle Tissue

   • Smooth Muscle
     • Spindle-shaped cells
     • Smooth, even stain
     • Involuntary
     • Arrector pili, blood vessels, gut tubes, respiratory tubes, bladder, ureters, uterus
   • Cardiac Striated Muscle
     • Striped apperance
     • Intercalated discs
     • Tubular cells, can branch
     • Involuntary pump
     • Heart only
   • Skeletal Muscle
     • Striped apperance
     • Voluntary
     • long tubular cells, no branching, many nuclei
     • Cells cannot divide
     • Most common tissue, 50% of body

3. Relationships

   • Fasiculus
     • Bundle of muscle cells, define by perimysium
   • Epimysium
     • Defines entire muscle
   • Fascia
     • holds unit of entire muscles
   • Tendon and Muscle Belly
     • Connective tissue extends beyond muscle cells
     • Tendon never ends, extends through muscle
   • Tendon and Bone
     • Tendon connective tissue spreads around bone and forms periosteum
     • Strong continuity of connective tissue/collagen

4. Microscopic Anatomy

   • Muscle cells
     • 0.1 to 0.5 mm diameter
     • few mm to 30 cm in length
   • Connective Tissue
     • Endomysium
       • fibrous, loose connective
       • wraps every individual cell
       • Perimysium
         • wraps around bundles of cells
         • DICT
         • Epimysium
           • wraps entire muscle
           • DICT
           • Fascia
             • wraps muscles together
             • DICT

5. Macroscopic Aantomy

   • Muscle Belly
     • Striated Skeletal
   • Tendons
     • DICT
     • attach to bone
       • Enthesis
         • fixed end/origin
           • proximal
           • stable, less mobile
         • Mobile end/insertion
           • Distal
           • Movement
     • both ends of muscle belly