Muscular System (CN) PDF

By: Dr. Sujatha  The Muscular System  Muscle tissue is distributed almost everywhere in the body, including over 600 named skeletal muscles 3  Muscles  Definition: A type of body tissues capable of contraction in order to cause movement....

By: Dr. Sujatha  The Muscular System  Muscle tissue is distributed almost everywhere in the body, including over 600 named skeletal muscles 3  Muscles  Definition: A type of body tissues capable of contraction in order to cause movement. The voluntary Skeletal muscles that moves the skeleton In viscera & Types Smooth blood vessels In heart Cardiac (myocardium)  Types of Muscle Tissue 1. Cardiac 2. Skeletal 3. Smooth (visceral) 5  Skeletal Muscle  Voluntary  Striated muscles  Attached to bones & cross joints  Attachment of skeletal muscle Origin Place where the fixed end of the muscle attaches to a bone or Origin cartilage; generally proximal to the insertion Belly Insertion Site where the Insertion movable end of the muscle attaches to another structure Attachment of skeletal muscle Tendon Aponeurosis Raphe external oblique abdominal muscles  Muscle functional groups Prime movers Synergists Antagonists Fixators Main Assist the Oppose the Stabilize the muscle prime prime origin of the producing mover mover prime the mover movement  Skeletal Muscle Structure Epimysium Dense irregular connective tissue fascia that envelopes entire muscle belly Perimysium Connective tissue septa that divides belly into fascicles - compartments containing fiber bundles Endomysium Fine connective tissue extensions of perimysium that envelop individual fibers 10 Principles of Muscles  Muscles of the upper limb Picture  Shoulder girdle  Upper arm  Forearm  Hand  Shoulder girdle  Muscles connecting upper limb to thoracic cage  Muscles connecting upper limb to vertebral column  Muscles connecting scapula to humerus Muscles connecting upper limb to thoracic cage  Pectoralis major  Pectoralis minor For flexion & adduction of the upper arm Muscles connecting upper limb to vertebral column  Trapezius Elevates the scapula  Latissimus dorsi Extends the upper arm Muscles connecting scapula to humerus  Deltoid  Muscles of upper arm  Anterior compartment  Posterior compartment  Anterior compartment  Biceps brachii Flexes the elbow Powerful supinator of the forearm triceps  Brachialis Powerful flexor of the elbow  Posterior compartment Triceps brachii.png Triceps triceps Extends the elbow joint  Muscles of forearm  Anterior compartment  Posterior compartment Anterior compartment Flexes the wrist and fingers  Posterior compartment forearm Extend hand & fingers  Muscles of the hand  Short muscles of the Hypothenar thumb eminence  Short muscles of the little Thenar eminence finger  Tendons of long flexors  Other small muscles  Muscles of the lower limb  Gluteal region  Thigh  Leg  Foot  Gluteal region 220px-Gluteus_muscles  Gluteus maximus 200px-Gluteus_maximus  Gluteus medius  Gluteus minimus  Gluteal region (cont.) 220px-Gluteus_muscles  Gluteus maximus Extends the hip joint  Gluteus medius Abduct the thigh  Gluteus minimus at hip joint  Muscles of the Thigh  Anterior compartment  Posterior compartment  Medial compartment Anterior Compartment of Thigh Quadriceps Femoris QF is a powerful extensor of knee  Posterior compartment of Thigh Hamstring group of muscles: Biceps femoris Flexors of Knee joint Medial compartment of Thigh Adductors of thigh  File:Gray437.png Muscles of the Leg  Anterior compartment  Posterior compartment  Lateral compartment Anterior compartment of leg File:Gray437.png Extensors of ankle & toes Extend Ankle joint & toes  Lateral compartment of leg Lateral compartment Peroneus flexion of ankle & longus eversion of foot Peroneus brevis Posterior Compartment of Leg File:Gray438.png Flexors of ankle & toes: Gastrocnemius & soleus Tibialis posterior (invert foot) Muscles of the Foot  Muscles of the thorax  Intercostal muscles  Diaphragm  Serratus posterior superior Intercostal  Serratus posterior muscles inferior Diaphragm Diaphragm  Muscles of the abdomen internal Oblique Abdominal (middle Muscles layer) Transversus Anterior posterior Abdominis abdominal wall abdominal wall (inner layer) External Quadratus Oblique Lumborum (outer layer) Psoas major Iliacus Rectus Abdominis  Muscles of the pelvis Levator Ani (Pelvic Diaphragm)  Muscles of the head Muscles of Muscles of the Muscles of facial scalp mastication expression  Muscles of the scalp  Occipitofrontalis  Muscles of facial expression Muscles of the eyelids Muscles of the lips Muscles of cheek Dilator: Levator palpebrae Orbicularis Obicularis oculi 9 dilator buccinator superioris oris muscles  Smooth Muscle Spindle-shaped cells Single nucleus centrally located Nonstriated and involuntary (ANS) Examples of location: blood vessels and glands, GIT, lower respiratory tract  Cardiac Muscle Main cylinder and collateral branches Normally a single, centrally located nucleus with intercalated discs Involuntary and autorhythmic (ANS)  Nerve supply of muscles  Smooth & cardiac muscles: Autonomic nerves  Skeletal muscles: somatic nerves (e.g. brachial & lumbosacral plexus)