40 Glossary: The Muscular System
- abduct
- move away from midline in the sagittal plane
- abductor digiti minimi
- muscle that abducts the little finger
- abductor pollicis brevis
- muscle that abducts the thumb
- abductor pollicis longus
- muscle that inserts into the first metacarpal
- abductor
- moves the bone away from the midline
- adductor brevis
- muscle that adducts and medially rotates the thigh
- adductor longus
- muscle that adducts, medially rotates, and flexes the thigh
- adductor magnus
- muscle with an anterior fascicle that adducts, medially rotates and flexes the thigh, and a posterior fascicle that assists in thigh extension
- adductor pollicis
- muscle that adducts the thumb
- adductor
- moves the bone toward the midline
- agonist
- (also, prime mover) muscle whose contraction is responsible for producing a particular motion
- anal triangle
- posterior triangle of the perineum that includes the anus
- anconeus
- small muscle on the lateral posterior elbow that extends the forearm
- antagonist
- muscle that opposes the action of an agonist
- anterior compartment of the arm
- (anterior flexor compartment of the arm) the biceps brachii, brachialis, brachioradialis, and their associated blood vessels and nerves
- anterior compartment of the forearm
- (anterior flexor compartment of the forearm) deep and superficial muscles that originate on the humerus and insert into the hand
- anterior compartment of the leg
- region that includes muscles that dorsiflex the foot
- anterior compartment of the thigh
- region that includes muscles that flex the thigh and extend the leg
- anterior scalene
- a muscle anterior to the middle scalene
- appendicular
- of the arms and legs
- axial
- of the trunk and head
- belly
- bulky central body of a muscle
- bi
- two
- biceps brachii
- two-headed muscle that crosses the shoulder and elbow joints to flex the forearm while assisting in supinating it and flexing the arm at the shoulder
- biceps femoris
- hamstring muscle
- bipennate
- pennate muscle that has fascicles that are located on both sides of the tendon
- brachialis
- muscle deep to the biceps brachii that provides power in flexing the forearm.
- brachioradialis
- muscle that can flex the forearm quickly or help lift a load slowly
- brevis
- short
- buccinator
- muscle that compresses the cheek
- calcaneal tendon
- (also, Achilles tendon) strong tendon that inserts into the calcaneal bone of the ankle
- caval opening
- opening in the diaphragm that allows the inferior vena cava to pass through; foramen for the vena cava
- circular
- (also, sphincter) fascicles that are concentrically arranged around an opening
- compressor urethrae
- deep perineal muscle in women
- convergent
- fascicles that extend over a broad area and converge on a common attachment site
- coracobrachialis
- muscle that flexes and adducts the arm
- corrugator supercilii
- prime mover of the eyebrows
- deep anterior compartment
- flexor pollicis longus, flexor digitorum profundus, and their associated blood vessels and nerves
- deep posterior compartment of the forearm
- (deep posterior extensor compartment of the forearm) the abductor pollicis longus, extensor pollicis brevis, extensor pollicis longus, extensor indicis, and their associated blood vessels and nerves
- deep transverse perineal
- deep perineal muscle in men
- deglutition
- swallowing
- deltoid
- shoulder muscle that abducts the arm as well as flexes and medially rotates it, and extends and laterally rotates it
- diaphragm
- skeletal muscle that separates the thoracic and abdominal cavities and is dome-shaped at rest
- digastric
- muscle that has anterior and posterior bellies and elevates the hyoid bone and larynx when one swallows; it also depresses the mandible
- dorsal group
- region that includes the extensor digitorum brevis
- dorsal interossei
- muscles that abduct and flex the three middle fingers at the metacarpophalangeal joints and extend them at the interphalangeal joints
- epicranial aponeurosis
- (also, galea aponeurosis) flat broad tendon that connects the frontalis and occipitalis
- erector spinae group
- large muscle mass of the back; primary extensor of the vertebral column
- extensor carpi radialis brevis
- muscle that extends and abducts the hand at the wrist
- extensor carpi ulnaris
- muscle that extends and adducts the hand
- extensor digiti minimi
- muscle that extends the little finger
- extensor digitorum brevis
- muscle that extends the toes
- extensor digitorum longus
- muscle that is lateral to the tibialis anterior
- extensor digitorum
- muscle that extends the hand at the wrist and the phalanges
- extensor hallucis longus
- muscle that is partly deep to the tibialis anterior and extensor digitorum longus
- extensor indicis
- muscle that inserts onto the tendon of the extensor digitorum of the index finger
- extensor pollicis brevis
- muscle that inserts onto the base of the proximal phalanx of the thumb
- extensor pollicis longus
- muscle that inserts onto the base of the distal phalanx of the thumb
- extensor radialis longus
- muscle that extends and abducts the hand at the wrist
- extensor retinaculum
- band of connective tissue that extends over the dorsal surface of the hand
- extensor
- muscle that increases the angle at the joint
- external intercostal
- superficial intercostal muscles that raise the rib cage
- external oblique
- superficial abdominal muscle with fascicles that extend inferiorly and medially
- extrinsic eye muscles
- originate outside the eye and insert onto the outer surface of the white of the eye, and create eyeball movement
- extrinsic muscles of the hand
- muscles that move the wrists, hands, and fingers and originate on the arm
- fascicle
- muscle fibers bundled by perimysium into a unit
- femoral triangle
- region formed at the junction between the hip and the leg and includes the pectineus, femoral nerve, femoral artery, femoral vein, and deep inguinal lymph nodes
- fibularis brevis
- (also, peroneus brevis) muscle that plantar flexes the foot at the ankle and everts it at the intertarsal joints
- fibularis longus
- (also, peroneus longus) muscle that plantar flexes the foot at the ankle and everts it at the intertarsal joints
- fibularis tertius
- small muscle that is associated with the extensor digitorum longus
- fixator
- synergist that assists an agonist by preventing or reducing movement at another joint, thereby stabilizing the origin of the agonist
- flexion
- movement that decreases the angle of a joint
- flexor carpi radialis
- muscle that flexes and abducts the hand at the wrist
- flexor carpi ulnaris
- muscle that flexes and adducts the hand at the wrist
- flexor digiti minimi brevis
- muscle that flexes the little finger
- flexor digitorum longus
- muscle that flexes the four small toes
- flexor digitorum profundus
- muscle that flexes the phalanges of the fingers and the hand at the wrist
- flexor digitorum superficialis
- muscle that flexes the hand and the digits
- flexor hallucis longus
- muscle that flexes the big toe
- flexor pollicis brevis
- muscle that flexes the thumb
- flexor pollicis longus
- muscle that flexes the distal phalanx of the thumb
- flexor retinaculum
- band of connective tissue that extends over the palmar surface of the hand
- flexor
- muscle that decreases the angle at the joint
- frontalis
- front part of the occipitofrontalis muscle
- fusiform
- muscle that has fascicles that are spindle-shaped to create large bellies
- gastrocnemius
- most superficial muscle of the calf
- genioglossus
- muscle that originates on the mandible and allows the tongue to move downward and forward
- geniohyoid
- muscle that depresses the mandible, and raises and pulls the hyoid bone anteriorly
- gluteal group
- muscle group that extends, flexes, rotates, adducts, and abducts the femur
- gluteus maximus
- largest of the gluteus muscles that extends the femur
- gluteus medius
- muscle deep to the gluteus maximus that abducts the femur at the hip
- gluteus minimus
- smallest of the gluteal muscles and deep to the gluteus medius
- gracilis
- muscle that adducts the thigh and flexes the leg at the knee
- hamstring group
- three long muscles on the back of the leg
- hyoglossus
- muscle that originates on the hyoid bone to move the tongue downward and flatten it
- hypothenar eminence
- rounded contour of muscle at the base of the little finger
- hypothenar
- group of muscles on the medial aspect of the palm
- iliacus
- muscle that, along with the psoas major, makes up the iliopsoas
- iliococcygeus
- muscle that makes up the levator ani along with the pubococcygeus
- iliocostalis cervicis
- muscle of the iliocostalis group associated with the cervical region
- iliocostalis group
- laterally placed muscles of the erector spinae
- iliocostalis lumborum
- muscle of the iliocostalis group associated with the lumbar region
- iliocostalis thoracis
- muscle of the iliocostalis group associated with the thoracic region
- iliopsoas group
- muscle group consisting of iliacus and psoas major muscles, that flexes the thigh at the hip, rotates it laterally, and flexes the trunk of the body onto the hip
- iliotibial tract
- muscle that inserts onto the tibia; made up of the gluteus maximus and connective tissues of the tensor fasciae latae
- inferior extensor retinaculum
- cruciate ligament of the ankle
- inferior gemellus
- muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
- infrahyoid muscles
- anterior neck muscles that are attached to, and inferior to the hyoid bone
- infraspinatus
- muscle that laterally rotates the arm
- innermost intercostal
- the deepest intercostal muscles that draw the ribs together
- insertion
- end of a skeletal muscle that is attached to the structure (usually a bone) that is moved when the muscle contracts
- intercostal muscles
- muscles that span the spaces between the ribs
- intermediate
- group of midpalmar muscles
- internal intercostal
- muscles the intermediate intercostal muscles that draw the ribs together
- internal oblique
- flat, intermediate abdominal muscle with fascicles that run perpendicular to those of the external oblique
- intrinsic muscles of the hand
- muscles that move the wrists, hands, and fingers and originate in the palm
- ischiococcygeus
- muscle that assists the levator ani and pulls the coccyx anteriorly
- lateral compartment of the leg
- region that includes the fibularis (peroneus) longus and the fibularis (peroneus) brevis and their associated blood vessels and nerves
- lateral pterygoid
- muscle that moves the mandible from side to side
- lateralis
- to the outside
- latissimus dorsi
- broad, triangular axial muscle located on the inferior part of the back
- levator ani
- pelvic muscle that resists intra-abdominal pressure and supports the pelvic viscera
- linea alba
- white, fibrous band that runs along the midline of the trunk
- longissimus capitis
- muscle of the longissimus group associated with the head region
- longissimus cervicis
- muscle of the longissimus group associated with the cervical region
- longissimus group
- intermediately placed muscles of the erector spinae
- longissimus thoracis
- muscle of the longissimus group associated with the thoracic region
- longus
- long
- lumbrical
- muscle that flexes each finger at the metacarpophalangeal joints and extend each finger at the interphalangeal joints
- masseter
- main muscle for chewing that elevates the mandible to close the mouth
- mastication
- chewing
- maximus
- largest
- medial compartment of the thigh
- a region that includes the adductor longus, adductor brevis, adductor magnus, pectineus, gracilis, and their associated blood vessels and nerves
- medial pterygoid
- muscle that moves the mandible from side to side
- medialis
- to the inside
- medius
- medium
- middle scalene
- longest scalene muscle, located between the anterior and posterior scalenes
- minimus
- smallest
- multifidus
- muscle of the lumbar region that helps extend and laterally flex the vertebral column
- multipennate
- pennate muscle that has a tendon branching within it
- mylohyoid
- muscle that lifts the hyoid bone and helps press the tongue to the top of the mouth
- oblique
- at an angle
- obturator externus
- muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
- obturator internus
- muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
- occipitalis
- posterior part of the occipitofrontalis muscle
- occipitofrontalis
- muscle that makes up the scalp with a frontal belly and an occipital belly
- omohyoid
- muscle that has superior and inferior bellies and depresses the hyoid bone
- opponens digiti minimi
- muscle that brings the little finger across the palm to meet the thumb
- opponens pollicis
- muscle that moves the thumb across the palm to meet another finger
- orbicularis oculi
- circular muscle that closes the eye
- orbicularis oris
- circular muscle that moves the lips
- origin
- end of a skeletal muscle that is attached to another structure (usually a bone) in a fixed position
- palatoglossus
- muscle that originates on the soft palate to elevate the back of the tongue
- palmar interossei
- muscles that abduct and flex each finger at the metacarpophalangeal joints and extend each finger at the interphalangeal joints
- palmaris longus
- muscle that provides weak flexion of the hand at the wrist
- parallel
- fascicles that extend in the same direction as the long axis of the muscle
- patellar ligament
- extension of the quadriceps tendon below the patella
- pectineus
- muscle that abducts and flexes the femur at the hip
- pectoral girdle
- shoulder girdle, made up of the clavicle and scapula
- pectoralis major
- thick, fan-shaped axial muscle that covers much of the superior thorax
- pectoralis minor
- muscle that moves the scapula and assists in inhalation
- pelvic diaphragm
- muscular sheet that comprises the levator ani and the ischiococcygeus
- pelvic girdle
- hips, a foundation for the lower limb
- pennate
- fascicles that are arranged differently based on their angles to the tendon
- perineum
- diamond-shaped region between the pubic symphysis, coccyx, and ischial tuberosities
- piriformis
- muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
- plantar aponeurosis
- muscle that supports the longitudinal arch of the foot
- plantar group
- four-layered group of intrinsic foot muscles
- plantaris
- muscle that runs obliquely between the gastrocnemius and the soleus
- popliteal fossa
- diamond-shaped space at the back of the knee
- popliteus
- muscle that flexes the leg at the knee and creates the floor of the popliteal fossa
- posterior compartment of the leg
- region that includes the superficial gastrocnemius, soleus, and plantaris, and the deep popliteus, flexor digitorum longus, flexor hallucis longus, and tibialis posterior
- posterior compartment of the thigh
- region that includes muscles that flex the leg and extend the thigh
- posterior scalene
- smallest scalene muscle, located posterior to the middle scalene
- prime mover
- (also, agonist) principle muscle involved in an action
- pronator quadratus
- pronator that originates on the ulna and inserts on the radius
- pronator teres
- pronator that originates on the humerus and inserts on the radius
- psoas major
- muscle that, along with the iliacus, makes up the iliopsoas
- pubococcygeus
- muscle that makes up the levator ani along with the iliococcygeus
- quadratus femoris
- muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
- quadratus lumborum
- posterior part of the abdominal wall that helps with posture and stabilization of the body
- quadriceps femoris group
- four muscles, that extend and stabilize the knee
- quadriceps tendon
- (also, patellar tendon) tendon common to all four quadriceps muscles, inserts into the patella
- rectus abdominis
- long, linear muscle that extends along the middle of the trunk
- rectus femoris
- quadricep muscle on the anterior aspect of the thigh
- rectus sheaths
- tissue that makes up the linea alba
- rectus
- straight
- retinacula
- fibrous bands that sheath the tendons at the wrist
- rhomboid major
- muscle that attaches the vertebral border of the scapula to the spinous process of the thoracic vertebrae
- rhomboid minor
- muscle that attaches the vertebral border of the scapula to the spinous process of the thoracic vertebrae
- rotator cuff
- (also, musculotendinous cuff) the circle of tendons around the shoulder joint
- sartorius
- band-like muscle that flexes, abducts, and laterally rotates the leg at the hip
- scalene muscles
- flex, laterally flex, and rotate the head; contribute to deep inhalation
- segmental muscle group
- interspinales and intertransversarii muscles that bring together the spinous and transverse processes of each consecutive vertebra
- semimembranosus
- hamstring muscle
- semispinalis capitis
- transversospinales muscle associated with the head region
- semispinalis cervicis
- transversospinales muscle associated with the cervical region
- semispinalis thoracis
- transversospinales muscle associated with the thoracic region
- semitendinosus
- hamstring muscle
- serratus anterior
- large and flat muscle that originates on the ribs and inserts onto the scapula
- soleus
- wide, flat muscle deep to the gastrocnemius
- sphincter urethrovaginalis
- deep perineal muscle in women
- spinalis capitis
- muscle of the spinalis group associated with the head region
- spinalis cervicis
- muscle of the spinalis group associated with the cervical region
- spinalis group
- medially placed muscles of the erector spinae
- spinalis thoracis
- muscle of the spinalis group associated with the thoracic region
- splenius capitis
- neck muscle that inserts into the head region
- splenius cervicis
- neck muscle that inserts into the cervical region
- splenius
- posterior neck muscles; includes the splenius capitis and splenius cervicis
- sternocleidomastoid
- major muscle that laterally flexes and rotates the head
- sternohyoid
- muscle that depresses the hyoid bone
- sternothyroid
- muscle that depresses the larynx’s thyroid cartilage
- styloglossus
- muscle that originates on the styloid bone, and allows upward and backward motion of the tongue
- stylohyoid
- muscle that elevates the hyoid bone posteriorly
- subclavius
- muscle that stabilizes the clavicle during movement
- subscapularis
- muscle that originates on the anterior scapula and medially rotates the arm
- superficial anterior compartment of the forearm
- flexor carpi radialis, palmaris longus, flexor carpi ulnaris, flexor digitorum superficialis, and their associated blood vessels and nerves
- superficial posterior compartment of the forearm
- extensor radialis longus, extensor carpi radialis brevis, extensor digitorum, extensor digiti minimi, extensor carpi ulnaris, and their associated blood vessels and nerves
- superior extensor retinaculum
- transverse ligament of the ankle
- superior gemellus
- muscle deep to the gluteus maximus on the lateral surface of the thigh that laterally rotates the femur at the hip
- supinator
- muscle that moves the palm and forearm anteriorly
- suprahyoid muscles
- neck muscles that are superior to the hyoid bone
- supraspinatus
- muscle that abducts the arm
- synergist
- muscle whose contraction helps a prime mover in an action
- temporalis
- muscle that retracts the mandible
- tendinous intersections
- three transverse bands of collagen fibers that divide the rectus abdominis into segments
- tensor fascia lata
- muscle that flexes and abducts the thigh
- teres major
- muscle that extends the arm and assists in adduction and medial rotation of it
- teres minor
- muscle that laterally rotates and extends the arm
- thenar eminence
- rounded contour of muscle at the base of the thumb
- thenar
- group of muscles on the lateral aspect of the palm
- thyrohyoid
- muscle that depresses the hyoid bone and elevates the larynx’s thyroid cartilage
- tibialis anterior
- muscle located on the lateral surface of the tibia
- tibialis posterior
- muscle that plantar flexes and inverts the foot
- transversospinales
- muscles that originate at the transverse processes and insert at the spinous processes of the vertebrae
- transversus abdominis
- deep layer of the abdomen that has fascicles arranged transversely around the abdomen
- trapezius
- muscle that stabilizes the upper part of the back
- triceps brachii
- three-headed muscle that extends the forearm
- tri
- three
- unipennate
- pennate muscle that has fascicles located on one side of the tendon
- urogenital triangle
- anterior triangle of the perineum that includes the external genitals
- vastus intermedius
- quadricep muscle that is between the vastus lateralis and vastus medialis and is deep to the rectus femoris
- vastus lateralis
- quadricep muscle on the lateral aspect of the thigh
- vastus medialis
- quadricep muscle on the medial aspect of the thigh