Muscles - appendicular Flashcards
Anterior Thorax - What does the subclavius muscle do?
- Stabilizes and depresses the pectoral girdle.
- Originates from the first rib and inserts into the clavicle.
Anterior Thorax - What is the function of the pectoralis minor?
- Draws the scapula forward and downward.
- Attaches from the ribs to the coracoid process of the scapula.
Anterior Thorax - What does the serratus anterior muscle do?
- Holds the scapula against the chest wall.
- Spans from the ribs to the anterior vertebral border of the scapula.
Posterior Thorax - What is the function of the trapezius muscle?
- Stabilizes, raises, retracts, and rotates the scapula.
- Extends from the occipital bone and vertebrae to the clavicle and scapula.
Posterior Thorax - What does the levator scapulae muscle do?
- Elevates and adducts the scapula.
- Runs from cervical vertebrae C1-C4 to the scapula.
Posterior Thorax - What is the function of the rhomboid muscles?
- Assists in squaring the shoulders and rotating the scapula.
- Located from the vertebrae to the scapula, deep to the trapezius.
Shoulder Joint - What does the pectoralis major do?
- Flexes, adducts, and medially rotates the arm.
- Large chest muscle, crucial for actions like climbing and pushing.
Rotator Cuff Muscles - What does the supraspinatus muscle do?
- Assists with arm abduction.
- Part of the rotator cuff, stabilizes the shoulder joint.
Shoulder Joint - What is the function of the latissimus dorsi?
- Prime mover of arm extension, adduction, and internal rotation.
- Active in activities like rowing and swimming.
Shoulder Joint - What is the role of the deltoid muscle?
- Prime mover of arm abduction.
- Can also facilitate flexion, extension, and rotation of the arm.
Rotator Cuff Muscles - What is the function of the infraspinatus muscle?
- Aids in lateral rotation and adduction of the arm.
- Part of the rotator cuff.
Rotator Cuff Muscles - What does the teres minor do?
- Works with the infraspinatus for lateral rotation and adduction of the arm.
- Part of the rotator cuff.
Rotator Cuff Muscles - What is the role of the subscapularis muscle?
- Contributes to medial rotation of the arm.
- Part of the rotator cuff.
Teres Major & Coracobrachialis
- What do the teres major and coracobrachialis muscles do?
- Act as synergists with the rotator cuff to stabilize and move the arm.
- Aid in internal rotation and adduction of the humerus.
Crossing the Elbow Joint - What does the brachialis muscle do?
- A major forearm flexor.
- Lifts the ulna as the biceps brachii lifts the radius.
Crossing the Elbow Joint - What is the function of the biceps brachii?
- Flexes the elbow and supinates the forearm.
- Originates from the scapula and inserts onto the radius.
Crossing the Elbow Joint - What is the role of the brachioradialis?
- Acts as a synergist in forearm flexion.
- Runs from the distal humerus to the distal radius.
Crossing the Elbow Joint - What is the function of the triceps brachii?
- Powerful extensor of the forearm, straightening the arm at the elbow.
- Contributes to shoulder joint stabilization.
Forearm - What are the two functional groups of forearm muscles?
- Muscles enabling wrist movement.
- Muscles controlling finger and thumb movements.
Forearm - What do the anterior forearm muscles do?
- Primarily flex the wrist and fingers.
- Attach to bones via the flexor retinaculum.
Forearm - What do the posterior forearm muscles do?
- Primarily extend the wrist and fingers.
- Attach to bones via the extensor retinaculum.
Forearm - What does the flexor carpi ulnaris muscle do?
- Flexes the wrist and adducts the hand.
- Stabilizes the wrist during finger extension.
- Originates from the humerus and ulna, extending to the metacarpals.
Forearm - What is the function of the flexor carpi radialis?
- Strong wrist flexor.
- Aids in hand abduction.
- Runs diagonally from the humerus to the metacarpals.
Forearm - What does the palmaris longus muscle do?
- Weak wrist flexor.
- Slightly assists in elbow flexion.
- Extends from the humerus to the palmar aponeurosis.
Forearm - What is the role of the pronator teres muscle?
- Primes forearm pronation.
- Functions as a weak elbow flexor.
- Runs from the humerus/ulna to the radius.
Forearm - What does the flexor digitorum superficialis muscle do?
- Flexes the wrist and middle phalanges of fingers 2-5.
- Originates from the humerus and ulna, inserts on the middle phalanges.
Forearm - What is the function of the flexor pollicis longus?
- Flexes the thumb, enabling grasping and pinching motions.
- Extends from the radius and interosseous membrane to the distal phalanx of the thumb.
Posterior Forearm - What does the extensor digitorum muscle do?
- Extends the fingers, wrist, and abducts the fingers.
- Originates from the humerus, inserts into the phalanges of the fingers.
Posterior Forearm - What do the extensor carpi radialis longus and brevis muscles do?
- Extend and abduct the wrist.
- Extend from the humerus to the second (longus) and third (brevis) metacarpals.
Posterior Forearm - What is the function of the extensor carpi ulnaris?
- Extends and adducts the wrist.
- Stretches from the humerus and ulna to the fifth metacarpal.
Posterior Forearm - What is the role of the supinator muscle?
- Assists the biceps brachii in supinating the forearm.
- Originates from the humerus and inserts onto the radius.
Posterior Forearm - What do the extensor pollicis longus and brevis muscles do?
- Extend the thumb at the carpometacarpal and interphalangeal joints.
- Originate from the radius, ulna, and interosseous membrane.
Lower Limb - What is the function of the intrinsic hand muscles?
- Responsible for fine motor control of fingers and thumb.
- Perform actions like flexion, extension, abduction, adduction, and opposition.
Lower Limb - What do the anterior muscles of the lower limb do?
- Primarily flex the femur at the hip and extend the leg at the knee.
- Important for the forward swing phase of walking.
Lower Limb - What is the function of the posterior muscles of the lower limb?
- Extend the thigh and flex the leg.
- Contribute to the backswing phase of walking.
Phases of Walking - What happens during the heel strike (initial contact) phase of walking?
The moment the heel touches the ground.
Lower Limb - What do the medial muscles of the lower limb do?
Primarily adduct the thigh.
Lower Limb - What are the general actions facilitated by muscles of the lower limb?
- Flexion
- extension
- abduction
- adduction
- circumduction
- rotation of the hip and leg.
Phases of Walking - What occurs during the loading response (foot flat) phase of walking?
The foot is flat, and the body begins to pass over the standing leg.
Phases of Walking - What happens during the midstance phase of walking?
The body weight is directly over the standing limb.
Phases of Walking - What happens during the preswing (toe off) phase of walking?
The toes leave the ground, preparing for the swing phase.
Phases of Walking - What occurs during the terminal stance (heel off) phase of walking?
The heel lifts off the ground, and the body moves in front of the foot.
Phases of Walking - What occurs during the initial and mid-swing phases of walking?
The leg is moving forward.
Phases of Walking - What happens during the terminal swing phase of walking?
The leg completes its forward motion and prepares for the next heel strike.
Anterior Thigh - What is the function of the iliopsoas muscle?
- A prime mover of hip flexion, crucial for walking, running, and lifting the leg.
- Originates from the iliac crest and T12 vertebrae, inserting into the femur.
Anterior Thigh - What does the sartorius muscle do?
- Flexes and laterally rotates the thigh at the hip and acts as a weak knee flexor.
- The longest muscle in the human body, originating from the anterior superior iliac spine.
Medial Thigh - What is the function of the pectineus muscle?
- Adducts, flexes, and medially rotates the thigh.
- Originates from the pubis and inserts into the femur.
Anterior Thigh - What is the role of the quadriceps femoris group?
- Extends the knee and flexes the thigh at the hip.
- Composed of rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius.
Medial Thigh - What do the adductor muscles (magnus, longus, brevis) do?
- Adduct, flex, and medially rotate the thigh.
- Important for walking and stabilizing the hip when the knee is flexed.
Medial Thigh - What is the function of the gracilis muscle?
- Assists in adducting the thigh and medially rotating the leg during activities like walking.
- Extends from the pubis to the medial tibia.
Posterior Thigh - What do the hamstrings do?
- Extend the thigh at the hip and flex the knee.
- Includes biceps femoris, semitendinosus, and semimembranosus.
Posterior Thigh - What is the role of the gluteus medius?
- Abducts and medially rotates the thigh.
- Important during walking.
Posterior Thigh - What does the gluteus maximus muscle do?
- Major extensor of the thigh, crucial for climbing stairs and running.
- Originates from the ilium, sacrum, and coccyx.
Leg - What muscles are responsible for dorsiflexion and toe extension?
- Extensor Digitorum Longus: Extends toes 2-5 and dorsiflexes the foot.
- Tibialis Anterior: Dorsiflexes the foot and assists in foot inversion.
- Extensor Hallucis Longus: Extends the great toe and assists in dorsiflexion.
Leg: lateral compartment - What do the fibularis longus and brevis muscles do?
- Plantar flex and evert the foot.
- Originate from the fibula and course underfoot to the metatarsals.
Leg: posterior compartment - What is the function of the gastrocnemius muscle?
- Enables plantar flexion of the foot when the knee is extended and flexes the knee when the foot is dorsiflexed.
- Inserts into the calcaneus via the Achilles tendon.
Leg: posterior compartment - What does the soleus muscle do?
- Powerful plantar flexor, active during walking, running, and dancing.
- Located deeper than the gastrocnemius, attaching to the calcaneus via the Achilles tendon.
Leg: posterior compartment - What is the function of the tibialis posterior?
- Prime mover of foot inversion.
- Originates from the tibia, fibula, and interosseous membrane.
Leg: posterior compartment - What does the flexor digitorum longus muscle do?
- Plantar flexes, inverts the foot, and flexes the toes.
- Aids in gripping and stability.
Leg: posterior compartment - What is the role of the flexor hallucis longus?
- Plantar flexes and inverts the foot.
- Flexes the great toe, crucial for push-off during walking and running.
What do the intrinsic muscles of the foot do?
- Assist in flexing, extending, abducting, and adducting the toes.
- Help with grasping and balancing, similar to intrinsic hand muscles.
