A&P 1 Muscle In-Lab Guide

Transcription

1 A&P 1 Muscle In-Lab Guide This lab guide includes a table with all the muscles you need to ID, along with their origins, insertions and actions Dashed lines means ignore. If several actions are listed, pay attention to the underlined action I will not test you on antagonists (as in what is the antagonist of the sternohyoid?. That is just so you will notice. The last page has study hints. It also has a you must know these muscle s actions list at the end, which tells you the top muscle actions to know for the Practical. Here is your plan of attack: Week 1: Get through the leg and arm muscles (except forearm save those for later). ID the muscles, and begin work on the origins and insertions, filling out the blank table provided with the wordlists. This Lab Guide has all the origins, insertions and actions you need to know. If several are listed on the table, pay special attention to underlined information. The Lab Guide area of the website has several images you can use to make a key. This is not necessary, but use them if it helps. Spring Break: Work on head, neck, torso and forearm. Week 2: Finish head, neck, torso and forearm. Review everything. Study Hints: 1. For origins and insertions, start off by knowing the bones, before you learn the specific features. For example, you get partial credit for knowing that the biceps brachii originates: "on the scapula" More partial credit for knowing "the Coracoid process of the scapula" And full credit for knowing "the Coracoid process and glenoid cavity of the scapula" 2. Study the insertions & actions together. They make sense together. Insertions are more important than origins. Make sure you LOOK at them!

2 Trends worth noting: 1. If a muscle crosses a joint, it moves it (action!) 2. Muscles on the anterior surface of the body tend to flex a joint (only true up to the!) 3. Muscles on the posterior surface of the body tend to extend a joint (only true up to the!) 4. Muscles on the lateral or medial surface of the torso or limb tend to adduct, abduct, and/or rotate a joint. Absolutely know these muscle s origins, insertions, & actions (80% of the ones on the exam): Temporalis Masseter Sternocleidomastoid Diaphragm Abdominal wall muscles (as a group) Pectoralis major Deltoid Rotator cuff (as a group) Latissimus dorsi Biceps brachii Triceps brachii Muscles that turn the elbow Flexor and Extensor carpi muscles Rectus femoris Vastus muscles (as a group) Gluteus maximus Hamstrings Medial adductors (as a group) Gastrocnemius And watch these structures: The IT-band The Achilles tendon The Quadriceps tendon

3 Make sure you find all the muscles you can on these models in the room: Dissected muscle model (find almost all of the muscles!) "Muscle Man" model (find all superficial muscles!!) Torso Model is especially good for thoracic and abdominal The sagittal head and whole head models are good to get close up to these muscles The arm and leg models come apart, so you can see deep muscles

4 A. Hip & Knee Joint (Anterior) - Flexing the Hip & Extending the Knee (usually) Q u a d r I c e p s Rectus femoris Vastus lateralis Vastus medialis Inferior iliac Linea aspera (ridge on posterior shaft) of femur Linea aspera (ridge on posterior shaft) of femur Patella and then to tibial tuberosity on anterior proximal end of tibia Same as above Same as above Extends at and flexes at hip (raises leg forward) Extends (straightens) at Extends (straightens) at Gastrocnemius, sartorius, gracilis and all 'hamstring' muscles all flex at, gluteus maximus and all 'hamstrings' extend at hip Gastrocnemius, sartorius, gracilis and all 'hamstring' muscles all flex at Gastrocnemius, sartorius, gracilis and all 'hamstring' muscles all flex at Vastus intermedius Anterior shaft of femur Same as above Extends (straightens) at Gastrocnemius, sartorius, gracilis and all 'hamstring' muscles all flex at NOTE: rectus femoris is the only one to cross the hip. The others originate on the femur! Sartorius Iliac spine of pelvic girdle Medial surface of tibia, near top Flexes at, flexes at hip (lifts leg forward), rotates hip outward (lateral). Combined motion results in sitting cross-legged Gluteus maximus and all 'hamstrings' extend at hip, all 'quadriceps' muscles extend at NOTE: sartorius is the only one that flexes both hip and!

5 B. Hip & Knee Joint (Posterior) Extending the Hip & Flexing the Knee G L U T S Gluteus maximus Tensor fasciae latae Ilium (crest of hip bone), sacrum, and coccyx Gluteal tuberosity of femur and Iliotibial band (call it the IT band) ---- Iliotibial band (call it the IT band) Extends at hip (draws leg back) and lateral rotation at hip (turns foot outward) Flexes at hip Rectus femoris flexes at hip (lifts leg forward), gluteus medius medial rotation at hip (turns foot inward) Not technically a glut, but assists. Gluteus maximus is the antagonist. Gluteus medius Abducts at hip (lifts leg away from midline) and medial rotation at hip (turns foot inward) Adductor group H A M S T R I N G S Biceps femoris Ischial tuberosity, linea aspera of femur Lateral proximal end of fibula and tibia Semitendinosus Ischial tuberosity Medial proximal end of tibia Semimembranosus Ischial tuberosity Medial proximal end of tibia Flexes at, extends at hip (draws leg backward) Flexes at, extends at hip (draws leg backward) Flexes at, extends at hip (draws leg backward) All 'quadriceps' muscles extend at, rectus femoris and sartorius flex at hip All 'quadriceps' muscles extend at, rectus femoris and sartorius flex at hip All 'quadriceps' muscles extend at, rectus femoris and sartorius flex at hip

6 C. Medial Thigh Adducting the Hip A D D U C T O R S ID the pectineus, adductor longus, adductor magnus. The adductor brevis is deep, and can't be seen easily on any model. Ischial & Pubic Bone near the Symphysis Medial Aspect of Femur gracilis Pubic symphysis Medial surface of tibia, near top D. Calf Muscles - Ankle Movement (mostly) Adduction of Thigh Adducts at hip (brings legs together at midline) also flexes (bends) at Gluteus medius abducts at hip, all 'quadriceps' muscle extend at gastrocnemius Medial and lateral condyles (posterior distal end) of femur Calcaneus via the calcaneal tendon (Achilles' tendon) Plantar flexion (stand on tip-toes) And flexes Tibialis anterior causes dorsiflexion soleus ---- Calcaneus (heel) Plantar flexion (stand on tip-toes) Tibialis anterior causes dorsiflexion tibialis anterior st metatarsal on medial edge of foot just above instep Dorsiflexion Soleus and gastrocnemius cause plantar flexion

7 E. Shoulder Joint Pectoralis major Clavicle, sternum, and rib cartilage Proximal humerus (intertubercular groove) Flexes at shoulder and adducts at shoulder Latissimus dorsi extends at shoulder (pulls arm across back of body); deltoid abducts at shoulder (lifts arm away from midline) Deltoid Spine and acromion process of scapula, clavicle Deltoid tuberosity If you contract the whole thing, it abducts at shoulder Can be used to flex at shoulder or extend at shoulder Both latissimus dorsi and pectoralis major adduct at shoulder (pull arm toward midline) Teres major Inferior angle of the scapula Humerus Rotator of Humerus ---- R O T A T O R C U F F Supraspinatus Infraspinatus Subscapularis Teres minor Supraspinous fossa Infraspinous fossa Subscapular fossa lateral border of the scapula Humerus greater turburcle Humerus greater turburcle Humerus greater turburcle Humerus lesser turburcle Stabilize Shoulder Joint ---- Stabilize Shoulder Joint ---- Stabilize Shoulder Joint ---- Stabilize Shoulder Joint ---- Rotator Cuff Group (know the individual names) The fossae of the Scapula Greater & Lesser Tubercles of Humerus Stabilize Shoulder Joint ---- Latissimus dorsi Spines of lower thoracic and lumbar vertebrae, sacrum, and iliac crest (crest of hip bone) Proximal humerus (intertubercular groove) Adducts and extends at shoulder Pectoralis major flexes at shoulder (pulls arm across front of body); deltoid abducts at shoulder (lifts arm away from midline) NOTE: the biceps brachii and triceps brachii also move the shoulder, although they are on the next table

8 F. Arm - Flex/Extend Elbow, Turn Forearm Biceps brachii Coracoid process and glenoid cavity of scapula Radial tuberosity of the radius (at the anterior proximal end of radius) Mainly, flexes arm at elbow. Also, supinates, forearm, and abducts and flexes shoulder triceps brachii extends at elbow (straightens arm) Brachialis Lower half of anterior humerus Proximal ulna flexes arm at elbow triceps brachii extends arm at elbow Triceps brachii Glenoid cavity of scapula, lateral and posterior portions of humerus Olecranon process of ulna Mainly, extends at elbow. Also adducts and extends at shoulder (pulls arm down and back) biceps brachii and Brachialis both flex at elbow Brachioradialis lateral epicondyle styloid process of the radius Flex elbow, supinates Supinator lateral epicondyle proximal portion of radius supinates pronator teres pronates (turns hand palm down or palm to the rear) Pronator teres medial epicondyle midway along the radius pronates supinator and biceps brachii both roll hand palm up or palm forward (supinate)

9 OVERVIEW G. Face, Skull & Neck Miscellany Epicranius (includes the frontalis and occipitalis) Cranial Aponeurosis None that we Platysma None that we Move Mandible Move Eye Move Mouth/lips Temporalis Temporal Fossa Coronoid Process Elevate Mandible None that we Masseter Zygomatic arch Angle and ramus of mandible Closes mouth and moves jaw from side to side as in chewing Orbicularis oculi Blinking, squinting None that we None that we Orbicularis oris Close Mouth None that we Zygomaticus Smiling Muscle None that we Digastric Swallowing None that we Swallowing Mylohyoid Mandible Hyoid Elevates hyoid Sternohyoid Sternohyoid Hyoid Sternum Depresses hyoid Mylohyoid Pharyngeal Constrictor Group They are very deep They are very deep Swallowing None that we

10 H. Moving the Head & Stabilizing the Scapula: Superficial & Deep Thorax Sternocleidomastoid Manubrium (upper part) of sternum and clavicle. Mastoid process of temporal bone (base of skull just behind and below the ear) Flexes at neck and rotates at neck (turns head to side) Trapezius extends at neck (tilts head back) Trapezius Spines of cervical and thoracic vertebrae, and occipital bone Spine of scapula and clavicle Shoulder joint - depresses (lowers) and adducts scapula. Also extends at neck (tilts head back) Serratus anterior Stabilize Scapulae Rhomboid (major and minor) Spine of thoracic vertebrae Medial border scapula Stabilize scapula Sternocleidomastoid flexes at neck (bows head forward) I. Thorax: Breathing (along with Sternocleidomastoid) Diaphragm Inferior Border of Rib Cage Breathing Pectoralis minor Breathing Internal & External Intercostals Border of Ribs Breathing J. Moving the Trunk: Abdominal Wall (note the aponeurosis) & Deep Back Rectus abdominis Pubic symphysis Sternum and cartilage of rib cage External & Internal Obliques Aponeurosis & Linea alba Flexes vertebral column (bends body forward); also increases abdominal pressure (when defecating, child birth) Synergist w/ Rectus Abdominis None that we Transverse abdominis Erector Spinae Group Aponeurosis & Linea alba Increases abdominal pressure (when defecating, child birth) Extension of Back

11 K. Arm - Flex/Extend Elbow, Wrist, & Fingers Palmaris longus Flexes fingers Extensor digitorum Flexor carpi ulnaris Medial epicondyle Anterior surface of medial metacarpals and carpals (pinkie side) Flexes wrist (bends forward) and lateral flex of hand at wrist Extensor carpi ulnaris and extensor carpi radialis both extend at wrist flexor carpi radialis abducts at wrist Flexor carpi radialis Medial epicondyle Anterior surface of lateral metacarpals (on thumb side of hand) Flexes wrist (bends forward) and medial flex hand at wrist Extensor carpi ulnaris and extensor carpi radialis both extend at wrist, flexor carpi ulnaris adducts at wrist Extensor digitorum (all) Extends fingers Palmaris longus Extensor carpi ulnaris Lateral epicondyle, and the proximal ulna Posterior surface of medial metacarpals and carpals (pinkie side) Extends wrist (bends forward) and lateral flex of hand at wrist Flexor carpi ulnaris and flexor carpi radialis both flex at wrist extensor carpi radialis abducts at wrist Extensor carpi radialis Lateral epicondyle Posterior surface of lateral metacarpals (on thumb side of hand) Extends wrist (bends forward) and medial flex hand at wrist Flexor carpi ulnaris and flexor carpi radialis both flex at wrist, extensor carpi ulnaris adducts at wrist Notice: Extensors originate on lateral epicondyle, flexors on the medial epicondyle Also, trends in nomenclature: "Digitalis" refers to "moves fingers" or "move phalanges" "Carpi" refers to "moves wrist" or "moves carpal bones" "Ulnaris" = pinkie-side "Radialis" = "thumb-side" Do you see any other trend in nomenclature??