Muscle & Fascia Lecture PDF

 Fascia Superficial fascia wy  Formed of loose areolar & fatty tissue deep to skin Character:...

 Fascia Superficial fascia wy  Formed of loose areolar & fatty tissue deep to skin Character: da  Thick in palm of the hand & sole of the foot  Thinnest over penis & external ear.  May be replaced by muscles as platysma in neck & dartos in scrotum en  May contain gland as mammary gland  Function: H  Fat is bad heat conductor keeping body temperature.  Fills up hollows of the body giving it round contour appearance R.  Facilitates movement of skin over the deep structures  It contains vessels & nerves of the skin D Anatomist “Fascia”  Deep fascia  Formed of membranous layer of connective tissue  Types: wy  Investing fascia: Enclose group of muscles. It gives origin to muscles. da  Inter-muscular septa: Lie between muscles. It gives origin to muscles & prevent spread of pus. en  Retinacula: Transverse thickenings of deep fascia at wrist & ankle.  Aponeurosis: H It holds the long tendons in place R. Thick part of deep fascia found in palm & sole It protects underlying structure  Sheath: D Found around neuro-vascular bundle Anatomist “Fascia”  Muscular system Skeletal muscles o Site: Attached to skeleton wy o Contraction: Voluntary o Nerve supply: Somatic da o Nuclei: prephiral & multi-nucleated o Striation: present en o Shape of cells: tubular H R. D Anatomist “Muscle”  Cardiac muscles o Site: myocardium o Contraction: involuntary wy o Nerve supply: autonomic o Nuclei: central & single-nucleated da o Striation: present o Shape of cells: branching en H R. D Anatomist “Muscle”  Smooth muscles o Site: viscera & blood vessels wy o Contraction: involuntary o Nerve supply: autonomic da o Nuclei: central & single-nucleated o Striation: absent en o Shape of cells: spindle H R. D Anatomist “Muscle”  Character of skeletal muscles wy o Origin of skeletal muscles: is the more fixed attachment o Belly of skeletal muscles: da the fleshy part of skeletal muscles o Insertion of skeletal muscles: en is the more mobile attachment o Tendon of skeletal muscles: o H cord-like structure at the insertion of skeletal muscles Aponeurosis of skeletal muscles R. sheet-like structure at the insertion of skeletal muscles D Anatomist “Muscle” Classification of skeletal muscles: A. According to arrangement of their fibers: wy 1. Muscles fibers parallel with the line of pull: 2. Oblique non pinnate muscles fibers: "convergent" da 3. Oblique pinnate muscles B. According to number of joints: en 1. Uni-articular: act on one joint as brachialis. H 2. Bi-articular: act on 2 joints as Sartorius. R. 3. Multi-articular: act on ≥ 2 joints as long flexors of digits. D Anatomist “Muscle” C. According to action of muscles: 1. Prime movers (agonist): Muscle that begins “initiates” the movement. wy As: brachialis for elbow flexion. 2. Antagonist: da Muscles that opposes the prime movers As.: triceps oppose brachialis en 3. Fixators (stabilizers): Muscle that stabilizes the joint H As rotator cuff muscles around shoulder R. 4. Synergists: Muscle that aid the prime mover by preventing the unwanted movement on proximal joint D while distal joints are in action As: extensors of wrist contract during flexion of fingers to eliminate the unwanted flexion at the wrist Anatomist “Muscle”