Appendicular muscles Flashcards
Appendicular Muscles
• muscles of the pectoral girdle and upper limb; and muscles of pelvic girdle and lower limb
deep fascia extends between bones and superficial fascia and separates muscles and soft tissues of upper limb and lower limbs into compartments
compartment syndrome
o when crushing injury, severe contusion or strain occurs blood vessels within one or more compartments may be damaged
♣ compartments become swollen with tissue, fluid and blood from damaged vessels
♣ escaped fluid cannot escape and pressure rises within affected compartments
♣ pressure compresses regional blood vessels – produces ischemia
• eliminating circulatory supply to muscles and nerves of compartment
o nerves destroyed after 2-4 hours, muscles after 6 hours
Pectoral Girdle and Upper Limb Muscles
muscles that position the pectoral girdle, move the arm, move the forearm and hand, move the hand and fingers
• Muscles that Position the Pectoral girdle
o pectoral girdle not locked to axial skeleton
o muscle connections position pectoral girdle, work in coordination with muscle of the arm and act as shock absorbers
o attachment of scapula to thorax (Fig 11.5, 11.6, Table 11.1) - trapezius, levator scapulae, rhomboids (major and minor), serratus anterior, pectoralis minor
♣ move and/or fixate scapula permitting wide range of movements of upper limbs
trapezius
♣ large triangular muscle covering back and portions of muscular ridge in superficial posterior part of neck
• origin = occipital protuberance, nuchal ligament and spinous processes of C7-T-12; insertion = clavicle, acromion process and scapular spine
• innervated by more than one nerve allowing specific regions of muscle to contract independently allowing varied actions
elevates or depresses, retracts, or rotates scapula and/or clavicle upward; extends neck
levator scapulae
♣ origin = transverse processes of C1-C4; insertion = superior vertebral border of scapula
• elevates scapula
rhomboids (major and minor
♣ origin = spinous processes C7-T5; insertion = vertebral border of scapula
• adducts (retracts) and rotates scapula downward (shoulders back)
serratus anterior
♣ – origin = anterior and superior margins of first 8 ribs; insertion = anterior surface of vertebral border of scapula
• abducts (protracts) and rotates scapula upward (shoulders forward)
pectoralis minor
♣ origin = anterior and superior margins of ribs 2-5; insertion = coracoid process of scapula
• depresses, abducts (protracts) and rotates scapula downward
attachement to clavicle
subclavius
o attachment to clavicle – trapezius, subclavius
♣ subclavius – origin = first rib; insertion = inferior border of clavicle
depresses clavicle; depresses and protracts scapula
Muscles that Move the Arm
o humerus attached to thorax by several muscles
deltoid _
arm muscle
♣ origin: clavicle, acromion process and scapular spine; insertion: deltoid tuberosity of humerus
• major abductor of arm; anterior fibers - flexion and medial rotation; posterior fibers - extension and lateral rotation of humerus (arm/shoulder)
rotator cuff muscles
arm muscle
♣ hold head of humerus to glenoid cavity of scapula
• form cup or cuff over proximal humerus
• 3 insert onto greater tubercle of humerus, 1 to lesser tubercle
o teres minor – origin = lateral border of scapula; lateral rotation and adducts humerus
o infraspinatus – origin = infraspinous fossa of scapula; lateral rotation of humerus
o supraspinatus – origin = supraspinous fossa of scapula; abducts humerus
o subscapularis – origin = subscapular fossa of scapula; medial rotation of humerus
• powerful repetitive arm movements can produce damage to one or more muscles or their tendons
teres major
♣ origin = inferior angle of scapula; insertion = intertubercular sulcus of humerus
• medial rotation and adducts humerus
pectoralis major
♣ origin: clavicle, sternum, six costal cartilages; insertion: lateral crest of the intertubercular sulcus of humerus
• flexion, adduction and medial rotation of humerus
coracobrachialis
♣ origin: coracoid process of scapula; insertion: medial margin shaft of humerus
• flexion and adduction of humerus
latissimus dorsi –
♣ origin spinous process of T7-L5 and ribs 8-12; insertion = intertubercular sulcus of humerus
• extension, adduction and medial rotation of humerus
Muscles the Move the Forearm and Hand
o most of muscles originate on humerus and insert on forearm and wrist
produce extension and flexion of the elbow, and supination and pronation of the forearm and hand
triceps brachii (forearm + hand)
o triceps brachii (and aconeus) (Fig 11.10) = main mass visible on posterior aspect of arm origin: 3 heads – long head = infraglenoid tubercle of scapula, lateral head = lateral margin of humerus, medial head = posterior surface of humerus; insertion: olecranon process of ulna ♣ extends ulna (elbow); long head – extension and adduction of humerus tennis elbow (lateral epicondylitis) – repetitive and forceful use of forearm extensor muscles, treatment = RICE (rest, ice, compression, elevation) and anti-inflammatory meds
o biceps brachii
o biceps brachii (Fig 11.8) = anterior aspect of arm
origin: long head - supragleniod tubercle of scapula, short head – coracoid process of scapula; insertion: radial tuberosity (medial side of radius)
♣ flexes shoulder and elbow, supinates forearm and hand
branchialis
o branchialis (Fig 11.8) = deep to biceps brachii – seen as mass on medial and lateral sides of arm
origin: distal half anterior surface of humerus; insertion: ulnar tuberosity and coronoid process
flexes elbow
brachioradialis
o = bulge on anterolateral side of forearm just distal to elbow,
origin: lateral supracondylar ridge of humerus; insertion: styloid process of radius
♣ flexes elbow
Flexors of the wrist
♣ superficial muscles on anterior surface of forearm
♣ medial to lateral = flexor carpi ulnaris, palmaris longus, flexor carpi radialis
♣ origin = medial epicondyle of humerus; insertion = carpal bones, bases of metacarpals, palmar aponeurosis and flexor reticulum
• flex wrist; radialis - abducts wrist; ulnaris – adducts wrist
Extensors of the wrist
♣ superficial muscles on posterior surface of forearm
♣ extensor carpi ulnaris, extensor carpi radialis longus and brevis
♣ origin = lateral epicondyle of humerus; insertion = bases of metacarpal bones
• extend wrist; radialis – abducts wrist; ulnaris – adducts wrist
supinator
o – origin: lateral epicondyle of humerus and ulna; insertion: radius (medial surface)
♣ supinates forearm and wrist
pronator teres
o origin: medial epicondyle of humerus and coronoid process of ulna; insertion: radius (lateral surface)
♣ and pronator quadratus – at distal end of ulna and radius
♣ pronates forearm and wrist
Muscles that Move the Hand and Finger movements
o extrinsic hand muscles = superficial and deep muscles of forearm but have tendons that extend into wrist
♣ anterior forearm muscles = flexion of fingers and thumb
• flexor digitorum superficialis and profundus – flex fingers
• flexor pollicus longus – flexion of thumb
♣ posterior forearm muscles = extension of fingers and thumb and abduction of thumb
• extensor digitorum, extensor indicis, extensor digiti minimi – extends fingers
• extensor pollicus longus and brevis, abductor pollicus longus – extend and abduct thumb
retinacula
o band of fibrous connective tissue that covers flexor (flexor reticulum) and extensor (extensor reticulum) tendons and their synovial tendon sheaths and holds them in place at the wrist
♣ carpal tunnel syndrome – edema or connective tissue deposition within carpal tunnel
• can restrict movement and compress median nerve resulting in tingling, burning and numbness of the hand (Clinical Note, p.296)
intrinsic hand muscles
o 20 muscles entirely within the hand but no origins on phalanges
♣ adduction and abduction of fingers and thumb, opposition (and reposition) of thumb, flexion and extension at the metacarpophalangeal joints
Pelvic Girdle and Lower Limb
• involves muscles that provide movement of the thigh, leg, foot and toes
• pelvic girdle has strong skeletal connection to axial skeletal
o increases strength
o limits range of motion
Muscles that move the Thigh
gluteal, lateral rotator, adductor, and iliosposas groups
o all groups originate on coxal bone (pelvis) and insert onto femur and/or iliotibial tract
iliotibial tract
♣ = band of collagen fibers (dense connective tissue) that extends along the lateral surface of the thigh and inserts onto the tibia
Gluteal group
– cover lateral surface of ilium
gluteus maximus
♣ largest and most superficial of group
• origin: posterior and lateral surface of ilium, sacrum and coccyx, insertion: iliotibial tract and gluteal tuberosity of femur
extension and laterally rotates thigh (hip); abducts thigh
gluteus medius
♣ superior and lateral to gluteus maximus, common site for injections
gluteus minimus
♣ deep to gluteus medius
• medius and minimus have a common origin: lateral surface of ilium, insertion: greater trochanter of femur
• abduct and medially rotate thigh
tensor fasciae latae
♣ smaller muscle portion proximally that becomes large aponeurosis (iliotibial tract) distally
• origin: anterior superior iliac spine and iliac crest; insertion: iliotibial tract to lateral condyle of tibia
• medially rotates thigh and stabilizes femur on tibia when standing
lateral rotator group (6 muscles
o deep to gluteus maximus
♣ piriformis, obturators (2), gemelli (2), quadratus femoris
♣ origin of muscles: near acetabulum, insertion: greater trochanter of femur
♣ lateral rotation and abduction of thigh
adductor group
o origins: pubis (inferior to acetabulum); insertion: medial aspect of linea aspera of femur; gracilis = medial surface of tibia – crosses 2 joints
♣ “pulled groin” = muscle tear or break in one of adductor muscles
♣ (lateral to medial) pectineus, adductor magnus, adductor brevis, adductor longus, gracilis
♣ adduct and flex thigh; most – medial rotation; gracilis – flexion and medial rotation of knee
iliopsoas group
o medial surface of pelvis
♣ psoas major and iliacus – origin = anterior surfaces and transverse processes T12-L5 and iliac fossa; insertion = lesser trochanter of femur
♣ flex thigh
Muscles that move the Leg
o muscles with action lines anterior to the axis of the knee = extensors of knee
♣ collectively = quadriceps femoris (Fig 11.18)
• common insertion: patella and tibial tuberosity via the petallar ligament
• knee extensors
rectus femoris
• lies in center of the group of muscles
o origin: anterior inferior iliac spine
o crosses two joints - hip flexion and knee extension
vastus intermedius
– lies deep to rectus femoris, origin: anterolateral surface of femur
vastus medialis
most medial of group, origin: linea aspera of femur
muscles with action lines posterior to the axis of the knee = flexors of knee
♣ hamstrings and sartorius (Fig 11.19)
♣ sartorius – longest muscle of body that diagonally crosses from lateral side of hip to medial side of knee
• origin: anterior superior iliac spine, insertion: medial side of tibial tuberosity
• crosses two joints – allows hip and knee flexion, lateral rotation and abduction of thigh - action required for crossing the legs
hamstrings
♣ all have common origin = on ischial tuberosity, cross two joints: hip and knee and
• extend hip and flex the knee
• biceps femoris – has two heads, short head = femur, insertion: head of fibula
o laterally rotates leg
• semimembranosus – insertion: medial condyle of tibia and collateral ligament of knee;
o medially rotates leg
• semitendinosus – insertion: tibia
o medially rotates leg
Muscles that Move Foot and Toes
o have extrinsic and intrinsic muscles groups
o Extrinsic muscles – produce plantar flexion, dorsiflexion, inversion or eversion of foot, and flexion and extension of toes
plantar flexion
• superficial muscle group – insertion = common tendon calcaneal (Achilles) tendon
o gastrocnemius – origin = lateral and medial condyles of femur
♣ crosses two joints - also flexes the knee
♣ together with soleus form the bulk of the calf
o soleus – origin = head and proximal shaft of fibula and posteromedial tibia
o plantaris - origin = lateral supracondylar ridge of femur
♣ crosses two joints - also flexes the knee
• deeper muscle group - aid in plantar flexion
o tendons seen on the lateral side of the ankle
o fibularis longus – origin = head and proximal shaft of fibula; insertion = first metatarsal and medial cuniform
♣ main action = eversion of foot
o fibularis brevis –origin = inferior lateral margin of fibula; insertion = fifth metatarsal
♣ main action = eversion of foot
o tibialis posterior – origin = interosseous membrane and shafts of tibia and fibula;
insertion = navicular, cuneiforms, cuboid, and second to fourth metatarsals
♣ main action = inversion of foot
dorsiflexion
• tibialis anterior – origin = lateral condyle and proximal shaft of tibia; insertion = medial cuniform and first metatarsal
o and inversion of foot
♣ digital extensors =
• main extensors of phalanges aid in dorsiflexion of foot
extensor digitorum longus – origin = lateral condyle of tibia and anterior surface of fibula; insertion = superior surfaces of phalanges 2-5
• extensor halluces longus – origin = anterior surface of fibula; insertion = superior surface distal phalanyx of great toe
♣ digital flexors (Fig 11.22)–
together with intrinsic muscle flex phalanges and aid in plantar flexion of foot
• flexor digitorum longus – origin = posteromedial surface of tibia; insertion = inferior surfaces phalanges 2-5
• flexor hallucis longus – origin = posterior surface fibula; insertion = inferior surface distal phalanyx of great toe
shin splits =
♣ pain associated with repetitive muscle stress of muscle attached along anterior tibial and fibular surfaces
• produces inflammation, stress fractures of tibia
intrinsic muscles
o 19 muscles within the foot itself (Fig 11.25, 11.26, Table 11.10)
♣ origins = tarsal and metatarsal bones; insertions = phalanges
♣ flex, abduct and adduct phalanges (minimal extension)
♣ muscles covered with thick fascia and plantar aponeurosis
♣ plantar fasciitis = inflammation of plantar aponeurosis resulting in pain over the heel and along the medial-inferior side of the foot
• cause – running on hard surface wearing poorly fitting or worn-out shoes
