9 Muscle Organization Flashcards
What are the four fascicles arrangements seen in muscles?
Parallel, pennate, convergent, and circular.
Describe parallel muscles and give an example
The fibers are parallel, e.g. Rectus abdominis or sartorius
Describe convergent fascicles arrangements and give examples
A broad origin converges toward insertion, e.g. Pectoralis major or latissimus dorsi
Describe a circular fascicle arrangement and give an example
Concentric rings of muscle fibers, e.g. Orbicularis oculi/orbicularis oris.
Describe a pennate fascicle arrangement and five and example.
Muscle fibers are short and obliquely attached to their connective tissue. There are three different classifications: unipennate, bipennate, and multipennate.
What is an example of a muscle which is unipennate?
Extensor digitorum
What is an example of muscle which is bipennate?
Rectus femoris
What is an example of a muscle which is multipennate?
Deltoid muscle.
What is the origin and insertion of the biceps brachii?
O: supraglenoid tubercle, coracoid process.
I: radial tuberosity
What is the origin and insertion of the brachialis muscle?
O: anterior shaft of the humerus
I: coranoid process.
What are the origins and insertions of the brachoradialis?
O: lateral supracondylar ridge of humerus
I: styloid process of radius
What are the origins and insertions of triceps brachii
O: infraglenoid tubercle of scapula and shaft of humerus
I: olecranon process of ulna
What muscles make up the rotator cuff?
Supraspinatus, infraspinatus, teres minor, subscapularis.
What are the origins and insertions of the supraspinatus muscle?
O: supraspinous fossa
I: greater tubercle of humerus
What are the origins and insertions of the infraspinatus?
O: infraspinous fossa
I: greater tubercle of humerus
What are the origins and insertions of the teres minor muscle?
O: lateral border of scapula
I: greater tubercle of humerus
What are the origins and insertions of the subscapularis?
O: subscapular fossa
I: lesser tubercle of humerus
What are the origins and insertions of the pectorals major muscle?
O: clavicle, sternum, ribs 2-6
I: intertubercular groove of the humerus
What are the origins and insertions of the teres major muscle?
O: lateral border and inferior angle of the scapula
I: intertubercular groove of the humerus
What are the origins and insertions of the latissimus dorsi muscle?
O: spinous processes of T7-T12, ribs 8-12, iliac crest, thoracolumbar fascia
I: intertubercular groove of humerus
What are the origins and insertions of the rectus femoris muscle?
O: anterior inferior iliac spine
I: tibial tuberosity
What are the origins and insertions of the vastus lateralis muscle?
O: greater trochanter and linea aspera
I: tibial tuberosity
What are the origins and insertions of the vastus intermedius muscle?
O: shaft of the femur
I: tibial tuberosity
What are the intertubercular groove muscles?
Pectoralis major, teres major, latissimus dorsi
What are the hamstring muscles?
Biceps femoris, semimembranosus, semitendinosus
What are the origins and insertions of the biceps femoris?
O: ischial tuberosity and linea aspera
I: head of fibula
What are the origins and insertions of the semimembranosus?
O: ischial tuberosity
I: medial condyle of tibia
What are the origins and insertions of the semitendinosus?
O: ischial tuberosity
I: pes anserinus
Where do all the hamstring muscles originate?
Ischial tuberosity
What is the most common and serious form of muscular dystrophy?
Duchenne muscular dystrophy
What are the symptoms of muscular dystrophy?
Muscles enlarge, but fibers atrophy. X-linked recessive gene. 1 out of every 3500 males is affected. Lack a protein called dystrophin.
What is inversion?
Foot turning medially. Plantar region opening toward medial malleolus.
What is eversion?
Turning laterally. Plantar region is exposed laterally towards lateral malleolus.
