Exam 2

Question 1

how many vertebrae are in the vertebral column?

Answer 1

33

Question 2

how many individual vertebrae are there?

Answer 2

24

Question 3

what is the organization of the vetebrae of the vertebral column?

Answer 3

7 cervical, 12 thoracic, 5 lumbar, 5 fused sacral (sacrum), 4 fused coccygeal (coccyx)

Question 4

what are pedicles?

Answer 4

processes that project dorsally to attach the body to the arch

“walls”

Question 5

what are laminae?

Answer 5

unite to form the spinous process

“roof”

Question 6

what fails to use in spina bifida?

Answer 6

laminae fail to fuse to form a spinous process

Question 7

compare the following types of spina bifida:

1. spina bifida occulta
2. spina bifida cystica
   a. with meningocele
   b. with meningomyelocele
   c. with myeloschisis or rachischisis

Answer 7

1. one or more spinous processes fail to form at lumbar or sacral levels; asymptomatic; marked by tuft of hair over defect usually
2. cyst protrudes through the defect
   a. cyst lined by the dura and arachnoid and contains CSF
   b. lumbosacral spinal cord is displaced into the cyst which stretches lumbosacral spinal nerves and may result in bladder, bowel, or lower limb weakness
   c. caudal end of the neural tube fails to close in the dorsal midline and is exposed on the surface of the back

Question 8

at what vertebral levels is spina bifida most commonly seen?

Answer 8

lumbar or sacral

Question 9

what are costal processes?

Answer 9

usually form transverse processes that project laterally at the junction between each lamina and pedicle

Question 10

label the components of the vertebrae

Answer 10

Question 11

what are the primary curvatures of the vertebral column and how are they directed? secondary curvatures?

Answer 11

primary are the thoracic and sacral curvatures, convex directed posteriorly

secondary are the cervical and lumbar curvatures, convex directed anteriorly

Question 12

what is kyphosis?

Answer 12

abnormal increase in the posterior curvature of the spine

thus, increased curvature in the thoracic or sacral regions

Question 13

what are possible causes of kyphosis? which is the most common?

Answer 13

postural (most common)

anterior wedge-shaped thoracic vertebrae

resorption of the anterior parts of the thoracic vertebral bodies from osteoporosis

Question 14

what is lordosis? what is a common cause?

Answer 14

abnormal increase in the anterior curvature of the spine

thus, increase in curvature in the lumbar or cervical regions

weakening of the anterior abdominal wall as a result of weight gain can cause

Question 15

what is scoliosis? what is a common cause?

Answer 15

abnormal lateral curvature that may be caused by an absent half of a vertebra or a wedge-shaped vertebra or by an asymmetric weakness of back musculature

Question 16

where are the zygapophyseal or facet joints located? what is their function?

Answer 16

between the facts of superior and inferior processes at the junction of each pedicle and lamina

permit gliding motion

acted on by intrinsic or deep back muscles

Question 17

where are intervetebral disks located? what are their components? what is their function?

Answer 17

situated between bodies of most adjacent vertebrae

consist of a fibrocartilaginous annulus fibrosus surrounding a nucleus pulposus

functions to absorb shock and distribute weight over the entire surface of vertebral bodies durring compression and tension

Question 18

what is the nucleus pulposis a remnant of?

Answer 18

fetal notochord

Question 19

where is the anterior longitudinal ligament found and what is its function?

Answer 19

covers the anterolateral parts of the vertebral boes and the disks to limit vertebral extension

Question 20

where is the posterior longitudinal ligament found and what is its function?

Answer 20

covers the posterior part of the vertebral codies and the disks and functions to limit vertebral flexion

Question 21

which is greater (thicker/stronger), the anterior or posterior longitudinal ligaments?

Answer 21

anterior

Question 22

where are the elastic ligamentum flavum and what are their functions?

Answer 22

between the laminae of adjacent vertebrae

function to limit vertebral flexion and help maintain normal vertebral curvatures

Question 23

where are the interspinous and supra spinous ligaments located?

Answer 23

interspinous ligaments a ligament connect the spinous processes of two adjacent vertebra

supraspinous ligaments a ligament connect the tips of the spinous processes of thoracic and lumbar vertebrae

Question 24

where are the intervertebral foramina located? what are they bounded by? what do they transmit?

Answer 24

an opening between the pedicles of adjacent vertebrae, separating individual vertebrae

bounded by the pedicles of adjacent vertebrae, posteriorly by facet joints and anteriorly by the bodies/intervertebral disks

transmit dorsal and ventral roots of the spinal nerves

Question 25

where/what is the vertebral canal? what does it contain?

Answer 25

the opening formed by the combination of the body and the vertebral arch as well as the ligaments/disks that interconnect them

contain the meninges, spinal cord, and roots of spinal nerves

Question 26

where is the epidural space and what does it contain?

Answer 26

outside the dural layer of the meninges and contains fat and the internal vertebral venous plexus

Question 27

what is the internal venous plexus? what is significant about it clinically in relation to cancer?

Answer 27

connects veins that drain the thorax, abdomen, and pelvis with dural venous sinuses of the cranial cavity

provides routes for metastasis of neoplasms of the prostate, uterus, and rectum to the cranial cavity

Question 28

what is the dura mater and where is it located?

Answer 28

outermost covering of the spinal cord, it forms the dural sac containing the spinal cord within vertebral canal

continuous with the meningeal dura of the cranial cavity and ends at S2, with lateral extensions at the roots of spinal nerves

Question 29

what is the subdural space?

Answer 29

potential space between the dura and the arachnoid mater

Question 30

what is the arachnoid mater and where is it located?

Answer 30

intermediate one of the three layers of meninges

also extends to S2 and is pressed against the dura by the pressure of CSF

Question 31

where is CSF contained in the spinal region?

Answer 31

the subarachnoid space (which has a spider web-like filaments)

Question 32

what is the normal pressure of CSF?

Answer 32

100 mm H20

Question 33

what is the function of CSF?

Answer 33

cushions the brain and spinal cord, absorbs waste products, transports hormones

has few cells, low protein content, and a lower glucose concentration than serum

Question 34

what is the pia mater?

Answer 34

covers the spinal cord and roots of the spinal nerves

most delicate of the meningeal layers

Question 35

what are the two specializations of pia mater and their functions?

Answer 35

denticulate ligaments: lateral extensions of the pia that anchor the spinal cord to the dura

filum terminale: consists of pia that extends from the inferior end of the cord at L2 and joins the dura and arachnoid to end in the sacral canal at S2

Question 36

what is the spinal cord located in relation to the vertebral column?

Answer 36

occupies he superior 2/3 of the vertebral canal and ends inferiorly at L2

Question 37

where/what is the conus medullaris?

Answer 37

tapered inferior end of the spinal cord that contains sacral and coccygeal cord segments and is located at L2

Question 38

going down the vertebral canal, where do spinal nerves exit?

Answer 38

first 7 cervical nerves exit SUPERIOR to the cervical vertebra for which they are named

beginning with T1, all other spinal nerves exit INFERIOR to the vertebra for which they are named

the 8th cervical nerve exits through intervertebral formen between C7 and T1 (8 cervical nerves, but only 7 cervical vertebrae)

Question 39

what forms the cauda equina and where is it located?

Answer 39

formed by dorsal and ventral roots of lumbar and sacral spinal nerves that extend inferior to the end of the spinal cord at L2

Question 40

what is a lumbar puncture and where is it typically performed?

Answer 40

used to sample CSF or introduce anesthetic agents into the subarachnoid space

typically performed between L4 and L5 below the inferior end of the spinal cord

Question 41

in a midline lumbar puncture, what layers will the needle transverse?

Answer 41

skin, superficial and deep fascia, supraspinous and interspinous ligaments, intralaminar space, epidural space, dura, arachnoid

Question 42

in an off the midline lumbar puncture, what will the needle transverse?

Answer 42

ligamentum flavum instead of the supraspinous and interspinous ligaments and the intralaminar space

Question 43

what are radiculopathies? what are typical symptoms?

Answer 43

compression of the roots of spinal nerves in the intervertebral foramina or in the vertebral canal

symptoms are pain and paresthesias in dermatomes supplied by affected sensory roots or weakness of skeletal muscles in myotomes supplied by compressed motor roots

Question 44

what can radiculopathies be caused by?

Answer 44

osteoarthritis- inflammation that results in additional bone growth by osteophytes at the facet joints

spondylitis- inflammation that results in additional bone growth by osteophytes at the margins of the vertebral bodies; anterior longitudinal ligament and sacroiliac joint may undergo calcification; may exhibit ankylosis (joint stiffening) or bamboo spine (marie-strumpell disease)

spondylosis- degenerative changes in intervertebral disks, usually combined with osteoarthritis at the margins of the vertebral bodies

Question 45

what are characteristics of the cervical vertebrae?

Answer 45

small bodies, short spinous processes (some with bifid tips), transverse processes that transmit vertebral arteries (have openings)

have facet joints of C3-C7 oriented at 45 degree angle relative to transverse plant–>permits flexion, extension, lateral bending, and rotation

uncinate processes on bodies of C3-C7 that form uncovertebral synovial joints with the vertebral bodies superior to them

Question 46

describe the location and characteristics of the atlas vertebra?

Answer 46

C1

has posterior arch and arnterior arch but no body or spinous process

no intervertebral disk in between C1 and C2

superior articular processes articulate with occipital condylesof the skull forming “yes” joints for flexion and extension

Question 47

describe the location and chracteristics of the axis vertebra?

Answer 47

C2

dens/odontoid process of the axis articulates with the anterior arch of the atlas and forms the “no” or pivotjoints to permit rotation of the atlas and skull

Question 48

what holds the dens in place and what is the function of the dens/associated ligaments? what can happen clinically if damaged?

Answer 48

dens held in place by transverse ligament of the atlas (rupture can cause dislocation of the atlantoaxial joint and displacement of the dens posteriorly into the cervical spinal cord and if the cord is compressed quadriplegia can result)

dens is attached to margins of the foramen magnum by alar ligaments (reupture can cause excessive rotation of the skull)

Question 49

describe the location and characteristics of vertebra prominens

Answer 49

C7

long spinous process and small transverse formina that does not transmit the vertebral arteries

Question 50

what is a herniated disk and which spinal nerves are they most likely to affect?

Answer 50

when a nucleus pulposis protrudes at the posterolateral part of an annulus fibrosus resulting in compression of roots of lower cervical or lower lumbar spinal nerves

the compressed roots are most commonly the more inferior spinal nerve (ex. at C5-6 disk, compresses C6 root)

Question 51

where do herniated disks most often occur at the cervical level?

Answer 51

at cervical levels, most common herniations between C6-C7–>C7 spinal nerve compression: referred pain in neck and shoulder and index and middle fingers; diminished triceps reflex and weakness in extension of forearm at the elbow or wrist and fingers

less common is at C7-C8–>C8 spinal nerve compression: pain in neck and shoulder and ring and little fingers; weakness in hypothenar and interosseous muscles of the hand

Question 52

what can occur with a cervical rib and what are the symptoms?

Answer 52

rib arising from costal process of C6

T1 spinal nerve and subclavian artery may be compressed as they course superior to cervical rib instead of first thoracic rib

diminished fadial pulse and pain and paresthesias in medial forearm

Horner’s syndrome signs seen (drooping of the eyelid (ptosis) and constriction of the pupil (miosis), sometimes accompanied by decreased sweating (anhidrosis) of the face on the same side)

Question 53

what are the characteristics of thoracic vertebrae?

Answer 53

“heart-shaped” or more rounded bodies ith ong obliquely oriented spinous processes

have costal facets on body and tranverse processes for articulation with ribs

also have facet joints oriented at a 60 degree angle relative to transverse plane which permits mainly lateral bending and rotation (flexion and extension limited by fixation by ribs)

Question 54

what are the characteristics of lumbar vertebrae?

Answer 54

large kidney-shaped bodies, short flat horizontally oritented spinous processes; long transverse processes

facet joints oriented perpendicular to the transverse plane for flexion, extension, and lateral bending with limited rotation

superior and inferior articular processes interconnected by an observable isthmus or pars interarticularis
–>“Scottie dog” shape

Question 55

what is spondylolysis?

Answer 55

defect or fracture of the isthmus with no anterior displacment of the vertebral body

Question 56

what is spondylolisthesis? where does it most commonly occur?

Answer 56

unilateral or bilateral defect or fracture of the isthmus accompanied by anterior displacement of the vertebral body

most commonly occurs between L5 and sacrum streching roots of lumbosacral spinal nerves in cauda equina

Question 57

where do herniated disks most often occur at the lumbar level?

Answer 57

between L4-L5–>compression of L5: results in sciatica (pain radiates from back into posterior thigh, anterolateral leg, and dorsum of the foot), weakness in extension of great toe and dorsiflexion (tibialis anterior)

between L5-S1–>compression of S1: pain and paresthesias in posterolateral leg, heel, and lateral side of foot; weakness in flexion of leg at knee (hamstring) and plantar flexion (gastrochemius and soleus), diminished Achilles tendon reflex

Question 58

what do the median crest of the sacrum and the intermediate crests represent?

Answer 58

median crests= fused sacral spinous processes

intermediate crests= fused articular processes

Question 59

what is the promontory?

Answer 59

forms ventral surface of the S1 vertebra (boundary of the pelvic inlet for obstretrics)

Question 60

what trasmist the dorsal and ventral rami of S1-S4?

Answer 60

four pairs of dorsal sacral foramina and four pairs of ventral sacral foramina

Question 61

what is contained in the sacral canal? the sacral hiatus?

Answer 61

canal, which ends at the sacral hiatus in the dorsal midline, contains the roots of the S1-coccygeal spinal nerves

sacral hiatus transmits the S5 and coccygeal spinal nerves

Question 62

where is an epidural or caudal block performed?

Answer 62

through sacral hiatus which diffuses through the meninges and anesthetizes the roots of the sacral and coccygeal spinal nerves in the cauda equina

Question 63

what forms the sacroiliac joints?

Answer 63

lateral surfaces of superior sacrum and medial surface of each ilium

Question 64

what is the coccyx attachment sites for?

Answer 64

gluteus maximum

anococcygeal ligaments which are attachment sites for muscles of pelvic diaphragm

Question 65

what are the muscle groups of the back?

Answer 65

superficial, intermediate, deep or intrinsic

Question 66

where do the superficial muscles of the back attach?

Answer 66

attached to pectoral girdle and act on the upper extremity

Question 67

what muscles are included in the superficial muscles of the back?

Answer 67

trapezius, latissimus dorsi, rhomboid major, rhomboid minor, levator scapulae

Question 68

what innervates the superificial muscles of the back?

Answer 68

ventral rami of spinal nerves through branches of the brachial plexus (except for trapezius which is supplied by CN XI/acessory nerve)

Question 69

where do the intermediate muscles of the back attach to?

Answer 69

attach to the ribs and act as acessory muscle of respiration

Question 70

what muscles are included in the intermediate muscles of the back?

Answer 70

serratus posterior superior, serratus posterior inferior, 12 pairs of levator costarum muscles

Question 71

what innervates the intermediate muscles of the back?

Answer 71

ventral rami of spinal nerves

Question 72

where do the deep/intrinsic muscles of the back attach?

Answer 72

attach mainly to transverse and spinous processes of vertebrae and act on the vertebral column at the intervertebral joints

Question 73

what muscles are included in the deep/intrinsic muscles?

Answer 73

erector spinae (contain 3 parallel muscle groups, from lateral to medial: iliocostalis, longissimus, and spinalis)

splenius capitis and splnius cervicis

transversospinalis muscles (consist of 3 muscle groups, superifical to deep: semispinalis, multifiduc, rotatores)

muscles of the suboccipital triangle

Question 74

what are the muscles of the erector spinae and what are their actions?

Answer 74

from lateral to medial: iliocostalis, longissimus, spinalis

acting bilaterally, extend the vertebral column at intervertebral joints

acting unilaterally, produce lateral bending of the vertebral column at intervertebral joints

Question 75

where are the splenius capitis and splenius cervicis located and what are their actions?

Answer 75

supeficial to erector spinae in the neck

spleni capitis acts to extend the head; splenius cervicis acts to rotate the head

acting unilaterally, both will produce lateral bending of the cervical vertebrae

Question 76

where are the transversospinalis muscles located? what are they and what are their actions?

Answer 76

deep to erector spinae

from superficial to deep: semispinalis, multifidus, rotatores

acting bilaterally, act to extend the vertebral column

acting unilaterally, produce rotation of the vertebral column

Question 77

what are the actions of the suboccipital triangle muscles?

Answer 77

contribute to the extension at the atlantooccipital joints and rotation at the atlantoaxial joints

Question 78

what innervates the deep muscles of the back?

Answer 78

dorsal rami of spinal nerves

Question 79

A 45-year-old man complains of low back pain that radiates into both lower limbs and leg weakness. An MRI scan reveals the body of the L5 vertebra is displaced laterally. A diagnosis of the patient’s condition would be:

A. spondylolysis
B. spondylosis
C. spondylitis
D. spondylolisthesis
E. spinal stenosis

Answer 79

D- spondylolisthesis- unilateral or bilateral defect or fracture of the isthmus accompanied by anterior displacement of the vertebral body–>bilateral lower back pain that radiates into both lower limbs and weakness in muscles of legs

spondylolysis-defect or fracture of the isthmus with no anterior displacement of the vertebral body

spondylosis- degenerative changes in intervertebral disks

spondylitis- inflammation that results in additional bone growth by steophytes at the margins of vertebral bodies; also calcification of anterior longitudinal ligament and sacroiliac joints–>anylosis (joint stiffening) and a bamboo spine (marie-srtumpell disease)

Question 80

A spinal anesthesia is used for a patient undergoing surgery. A lumbar puncture is performed in the midline between L4 and L5. Which of the following will not be transvered?

A. interspinous ligament
B. posterior longitudinal ligament
C. epidural space
D. arachnoid
E. dura

Answer 80

B. posterior longitudinal ligament- covers posterior parts of the vertebral bodies and intervening disks and is anterior to the dural sac

Question 81

Which of the following structures in the vertebral canal will be anesthetized in a spinal procedure?

A. dorsal and ventral rami
B. lumbar spinal nerves
C. sacral spinal nerves
D. dorsal and ventral roots
E. lumbosacral plexus

Answer 81

D. dorsal and ventral roots are in the cauda equina found in the vertebral canal (others are found in intervertebral foramen or outside of the vertebral canal)

Question 82

An MRI reveals a patient has a posterolateral herniation of the nucleus pulposus of the intervertebral disk between L5 and the sacrum. Which might you observe?

A. weakness in dorsiflexion
B. altered sensation on the dorsum of the foot
C. weakness in plantar flexion
D. altered sensation in the anterior thigh
E. weakness in extension of the leg at the knee

Answer 82

C. roots of S1 compressed which results in altered sensation in posterolateral leg, heel lateral side of the foot, weakness in flexion of the leg at the knee, weakness in plantar flexion

Question 83

A 50-year-old man complains of bak pain and has difficulty walking. Diagnostic imaging reveals calcifications of the sacroiliac joints and anterior longitutinal ligament resulting from additional bone growth by osteophytes. This suggests the patient has:

A. spondylitis
B. spondylosis
C. spondylolysis
D. spinal stenosis
E. scoliosis

Answer 83

A. spondylitis

Question 84

A 64-year-old man presents with pain that radiates from the back, through the posterior thigh, and into the leg and foot. The diagnosis is a herniated nucleus pulposus of the intervertebral disk between the L4 and L5 vertebrae. What else might the patient experience?

A. altered sensation in the L3 dermatome
B. weakness of muscles innervated by the L5 spinal cord segment
C. inability to contract and empty the bladder
D. fecal incontinence
E. weakness in the ability to extend the leg at the knee

Answer 84

B. from compression of L5

Question 85

A patient develops a peripheral neuropathy that results in the degeneration of nerve fibers in dorsal rami. All of the following may be evident EXCEPT:

A. sensation may be altered in skin covering the trapezius
B. iliocostalis muscle might be weak
C. axons firing through the dorsal sacral foramina may be affected
D. motor fibers in the dorsal scapular nerve may be affected
E. sensation from facet joints may be altered

Answer 85

C. dorsal scapular nerve is a ventral ramus of the C5 spinal nerve (few dorsal rami have names)

Question 86

Your patient suffers from a herniated disk between the L5 vertebra and the sacrum. If the herniation is small, what neural structure might be subject to compression?

A. L4 spinal nerve
B. L5 spinal nerve
C. S1 spinal nerve
D. conus medullaris
E. lumbar splanchnic nerve

Answer 86

C- S1 spinal nerve

Question 87

what does the pelvic girdle consist of? where do those parts fuse? what are its joints?

Answer 87

ilium, ishium, pubis

fushed together at the acetabulum

sacroiliac joints and hip joints

Question 88

what is the function of the pelvic girdle?

Answer 88

it suspends lower limb away from the axial skeleton to increase range of motion

girdle itself has limited mobility

Question 89

what type of joint is the sacroiliac joint?

Answer 89

gliding joint

Question 90

what ligaments resist motion at the sacroiliac joints?

Answer 90

posterior sacroiliac ligaments

Question 91

what type of joint is the hip joint?

Answer 91

ball and socket

Question 92

what ligaments strengthen the articular capsule of the hip joint? what do they reinforce? what motions do they resist?

Answer 92

1. iliofemoral ligament- strongest in the hip joint; reinforces anterior part of capsule; resists extension
2. pubofemoral ligament- reinforces the anterior and inferior parts of the capsule; resists abduction
3. ischiofemoral ligament- reinforces the posterior part of the capsule; resists extension by screwing the femoral head into the acetabulum

Question 93

what can happen as the result of a fracture of the femoral head?

Answer 93

avascular necrosis (from disruption of the medial circumflex femoral artery which is the main arterial blood source to head and neck)

patients will have thigh laterally rotated by short lateral rotators of the thigh at the hip and by the gluteus maximus

Question 94

a dislocation of the head of the femur most commonly occurs in what direction?

Answer 94

posterior

Question 95

what can occur as the result of dislocation of the head of the femur?

Answer 95

thigh is shortened and medically rotated by gluteus medius and minimus muscles

sciatic nerve may be compressed (resulting in weakness of muscles in the posterior thigh, leg, and foot and paresthesia over the posterior and lateral parts of the leg and the dorsal and plantar surfaces of the foot)

Question 96

what makes up the knee joint and what type of joint is it?

Answer 96

medial and lateral condyles of the femur and tibeal plateau

modified hinge-joint

Question 97

what ligaments of the articular capsule and ligaments within the articular capsule strengthen the knee?

Answer 97

patellar ligament

oblique popliteal ligament

fibular and tibial collarteral ligaments

anterior cruciate ligament

posterior cruciate ligament

(ACL and PCL are intracapsular)

Question 98

what is the patellar tendon an extension of? what parts of the knee capsule does it strength?

Answer 98

extension of the quadriceps tendon

strengthens the anterior and lateral parts

Question 99

what does the oblique popliteal ligament arise from and what part of the capsule does it strengthen?

Answer 99

part of the semimembranosus tendon

posterior part of the capsule

Question 100

where do the fibular and tibial collateral ligaments originate and attach to? what parts of the joint to they support?

Answer 100

fibular: supports lateral part of joint; extends from the lateral epicondyle of the femur to attach to head of the fibula; same as lateral collateral ligament (LCL)
tibial: supports medial part of the joint: extends from the medial epicondyle of the femur to attach to the medial aspect of the tibia and deep fibers are attached to medial meniscus; same as medial collateral ligament (MCL)

Question 101

what motions do the fibular and tibial collateral ligaments limit?

Answer 101

abduction and adduction of the knee when knee is flexed

Question 102

where do the ACL and PCL originate and attach?

Answer 102

ACL= APEX ligament… attaches to Anterior aspect of the tibia and courses Posteriorly and EXternally/laterally to attach to lateral condyle of the femur

PCL= PAIN ligament… attaches to Posterior aspect of the tibia and courses Anteriorly and INternally/medially to attach to the medial condyle of the femur

Question 103

what motions do the ACL and PCL resist? when is each most taut? which is weaker?

Answer 103

ACL is weaker than the PCL

ACL is most taut during knee extension; resists hyperextension by preventing antior displacement of the tibia on the femur

PCL is most taut when knee is flexed and resists excessive flexion by preventing posterior displacement of the tibia on the femur

*anterior drawer test vs. posterior drawer test

Question 104

compare the medial and lateral menisci (where are they, their shape, mobility)

what is their main function?

Answer 104

both are intracapsular, fibrocartilages that attach to tibia and act as shock absorbers

medial meniscus: shape of C and is less mobile; attached to deep fibers of the tibial collateral ligament

lateral meniscus: shape of o; more mobile; separated from the fibular collatoeral ligament by the tenson of the popliteus

Question 105

what are the three most common injuries at the knee? (terrible triad)

Answer 105

tibial collateral ligament (MCL), medial meniscus, ACL

Question 106

when can a “terrible triad” injury of the knee occur? when is only the ACL torn not the other two? what signs will be exhibited with either of the situations?

Answer 106

blow to lateral aspect of the knee when foot is on the ground can sparin the tibial collateral ligament and tear the attached medial meniscus

patients with a medial meniscus tear will have pain when lef is medially rotated at the knee

ACL tears can occur when TCL and MM are injured or a blow to anterior aspect of flexed knee can tear only ACL

torn ACL will exhibit an anterior drawer sign- tibia may be displaced anteriorly form the femur in the flexed knee

Question 107

does the fibula articulate with the knee joint?

Answer 107

no, not directly

it does articulate with the tibia and talus

Question 108

what are the ankle joints?

Answer 108

talocrural, subtalar, and transver tarsal joints

Question 109

what is the talocrural joint formed by and what type of joint is it?

Answer 109

formed by articulation between the trochlea of the talus and the lateral and medial malleoli of the fibula and tibia, respectively

hinge joint (permits dorsiflexion and plantarflexion)

Question 110

is the foot more stable in dorsiflexed position or plantarflexed? why?

Answer 110

dorsiflexed

anterior part of the superior surface of the trochlea of the talus is wider than the posterior part of the talocrural joint

Question 111

which tendons enter the sole of the foot after passing posterior and inferior to the medial malleolus?

Answer 111

tendons of the tibialis posterior, flexor digitorum longus, flexor hallucis longus muscles

Question 112

what tendons enter the sole of the foot after passing posterior and inferior to the lateral malleolus?

Answer 112

tendons of the fibularis/peroneus longus and fibularis/peroneus brevis muscles

Question 113

what ligaments strengthen the talocrural joint? which is the stronger of the two?

Answer 113

deltoid/medial ligaments and lateral ligaments

deltoid is stronger

Question 114

the deltoid ligament has __ components… what are they?

Answer 114

4 components

• anterior and posterior tibiotalar
• tibiocalcaneus
• tibionavicular

Question 115

the lateral ligaments has __ components… what are they?

Answer 115

3 components

• anterior and posterior talofibular
• calcaneofibular ligament

Question 116

are inversion or eversion ankle sprains more common at the talocrural joint? what ligament and what part of the lateral ligament is most commonly torn during that?

Answer 116

inversion ankle sprains

the anterior talofibular part of the lateral ligament

Question 117

what forms the subtalar joint and what type of joint is it?

Answer 117

articulation between the talus and calcaneus

ball and socket joint

Question 118

what actions does the subtalar joint permit and what are they?

Answer 118

supination- combination of plantar flexion, inversion and adduction

pronation- combination of dorsiflexion, eversion, and abduction

Question 119

what forms the transverse tarsal joints? what motions do the joint allow?

Answer 119

formed by the articulation of the talus with the navicular and the calcaneus with the cuboid

contribute to inversion and eversion with the subtalar joint

Question 120

what muscles generally are contained in the sole of the foot?

Answer 120

short abductors and flexors of the great toe and little toe, respectively

(lacks the eminences and opponens muscles of the hand)

Question 121

what is the action of the quadratus plantae muscle?

Answer 121

plantar muscle that acts to straighten out the oblique pull of the flexor digitorum longus tendons

(no counterpart in the hand)

Question 122

what is the course of the femoral artery (origin, path, areas supplied)?

Answer 122

begins at the inguinal ligament from the extnal iliac artery

courses lateral to the femoral vein and medial to the femoral nerve through the femoral triangle in the anterior thigh

enters adductor canal to become the popliteal artery (after passing through the adductor hiatus)

profunda femoral artery gives rise to lateral and medial circumflex arteries–>thigh, head and neck of femur, hip joint (medial is main source for the head and neck of femur)

profunda artery also gives rise to 4 perforating arteries that supply the medial thigh and pass through the adductor magnus to supply the muscles in the posterior thigh

Question 123

what is the cruciate anastomosis? what is its clinical importance?

Answer 123

medial and lateral circumflex femoral arteries, inferior gluteal atery, and first perforating artery contribute to cruciate anastomosis in the posterior thigh

can contribute to collateral circulation of lower limb is the femoral artery becomes occluded

Question 124

what is the course of the popliteal artery?

Answer 124

beings at the adductor hiatus as a continuation of the femoral artery

courses through the popliteal fossa posterior to the knee with the tibial nerve

gives rise to 5 genicular arteries that supply the knee joint

ends when it divides into the anterior and posterior tibial arteries at the inferior border of the popliteus

Question 125

what is the course of the anterior tibial artery and what does it supply?

Answer 125

enters the anterior compartment of the leg proximal to the interosseous membrane between the tibia and fibula

courses with the deep fibular/peroneal nerve and supplies the anterior compartment of the leg

continues as the dorsalis pedis

Question 126

what is the course of the dorsalis pedis, what are its branches and what do they supply?

Answer 126

comes from the anterior tibial artery, on the dorsal aspect of the foot

branches into an arcuate artery, which gives rise to digital branches that supply the toes and a deep plantar artery, which contributes to a plantar arterial arch in the sole of the foot

Question 127

where would one feel for the dorsalis pedis pulse?

Answer 127

compressing the dorsal artery of the foot against the tarsal bones lateral to the tendon of the extensor hallucis longus

Question 128

what is the course of the posterior tibial artery? what are its branchs and what do they supply?

Answer 128

arises from the popliteal artery and courses through posterior compartment of leg with the tibial nerve

supplies the posterior compartment of the leg

gives rise to the fibular artery–>supplies the posterior leg and sends perforating branches into lateral compartment of the leg (fibularis longus and brevis muscles)

passes into foot (behind the medial malleolus) to divide into medial and lateral plantar arteries–>supply sole of the foot

Question 129

what are the branches of the internal iliac artery?

Answer 129

superior gluteal artery

inferior gluteal artery

obturator artery

Question 130

what is the course of the superior gluteal artery and what does it supply?

Answer 130

enters the gluteal region with superior gluteal nerve superior to the piriformis after passong through the greater sciatic foramen

supplies the gluteus medius and minimus, some of maximus

Question 131

what is the course of the inferior gluteal artery and what does it supply?

Answer 131

enters the gluteal region with the inferior gluteal nerve inferior to the priformis muscle after passing through the greater sciatic foramen

supplies the gluteus maximus, short lateal rotators of the hip, promixal parts of the hamstrings

Question 132

what is the course of the obturator artery and what does it supply?

Answer 132

enters the medial thigh with the obturator nerve, after passing through the obturator foramen

supplies the adductor muscles, obturator externus, pectineus, and gracilis muscles

Question 133

which veins of the lower limb are superficial?

Answer 133

great saphenous and small saphenous veins

Question 134

what is the course of the great saphenous vein?

Answer 134

arises from medial aspect of the dorsal venous arch of the foot

courses anterior to the medial malleolus, though medial aspect of the leg (with the saphenous nerve) and through the medial thigh

drains into the femoral vein after passing through the saphenous hiatus (fault in fascia lata)

Question 135

what is the course of the small saphenous vein?

Answer 135

arises from the lateral aspect of the dorsal venous arch of the foot

courses posterior to the lateral malleolus and then through the posterior leg (with the sural nerve)

passes between the two heads of the gastrocnemius muscle and drains into the popliteal vein

Question 136

in general, what are the deep veins of the lower limb and where do they course?

Answer 136

course with arteries of the same name (arteries from the iliac, femoral, politeal, posterior and anterior tibial arteries)

Question 137

what nerve plexuses innervate the lower limb and where can they be found?

Answer 137

lumbar plexus: formed by ventral rami of L1-L4 (partly T12) and is found on posterior abdominal wall and greater plexus

lumosacral plexus: formed by ventral rami of L4-S3 and found in the lesser pelvis

Question 138

what do the ventral rami of the lumbar plexus branch into (divisions and nerves)?

Answer 138

posterior division–>femoral nerve

anterior division–>obturator nerve

Question 139

what do the ventral rami of the lumbosacral plexus divide into (divisons and nerves?)

Answer 139

posterior–>common fibular/peroneal (superior and inferior gluteal nerves also contain posterior division fibers)

anterior–>tibial nerves

Question 140

During development, the lower limb undergoes a ______ rotation so that flexor muscles that were in the _____ embryo are then situated ______ and extensor muscles that were ____ in the embryo come to be situated ______. As a result the medial and posterior compartments of the thigh, the posterioer compartment of the leg, and the plantar muscles of the foot are innervated by the _____ or ____ nerves, which contain _____ division fibers. Muscles in the anterior compartment of the thigh and anterior and lateral compartments of the leg and the dorsum of the foot are innervated by the _____ or ______ nerves, which contain ______ division fibers.

Answer 140

During development, the lower limb undergoes a MEDIAL rotation so that flexor muscles that were in the ANTERIOR embryo are then situated POSTEROMEDIALLY and extensor muscles that were POSTERIOR in the embryo come to be situated ANTEROLATERALLY. As a result the medial and posterior compartments of the thigh, the posterioer compartment of the leg, and the plantar muscles of the foot are innervated by the OBTURATOR or TIBIAL nerves, which contain ANTERIOR division fibers. Muscles in the anterior compartment of the thigh and anterior and lateral compartments of the leg and the dorsum of the foot are innervated by the FEMORAL or COMMON FIBULAR nerves, which contain POSTERIOR division fibers.

Question 141

what forms the lumbosacral trunk and what is its course?

Answer 141

fibers of L4 and L5 form the lumbosacral trunk

lumbosacral trunk emerges from medial aspect of the psoas major, corsses the pelvic brim, joins with the ventral rami of S1-S3 to form the lumbosacral plexus

Question 142

where do the terminal and collateral nerves of the lumbosacral plexus exit the pelvis?

Answer 142

greater sciatic foramen

Question 143

The nerves from the superior rami of the lumbar and lumosacral plexus (L2-L4) innervate muscles where? and thus at on what joints?

Answer 143

anterior and medial thigh

acting on hip and knee joints

Question 144

The nerves that contain fibers from the inferior rami of the lubar and lumbosacral plexus (#1-S3) innervate what muscles? and thus act on what joints?

Answer 144

the leg

joints of the ankle and foot

Question 145

the femoral nerve contains posterior division fibers from which ventral rami?

Answer 145

L2-L4

Question 146

what is the course of the femoral nerve? what does it innervate?

Answer 146

emerges from lateral border of the psoas major in the iliac fossa and passes into the anterior thigh, posterior to the inguinal ligament and lateral to the femoral artery

innervates muscles in the anterior compartment of the thigh: 4 heads of quadriceps femoris, iliopsoas, sartorius, pectineus (which all act to flex thigh at hip and extend leg at knee)

innervates skin of the anterior and medial thigh (medial and intermediate cutaneous nerves)

also gives rise to the saphenous nerve

Question 147

what is the longest branch of the femoral nerve and the only branch of the lumbar plexus to cross the knee joint?

Answer 147

saphenous nerve

Question 148

what is the course of the saphenous vein and what does it innervate?

Answer 148

branch from femoral

enters adductor canal but leaves without passing through the adductor hiatus

courses with the great saphenous vein and innervates the skin of the medial side of the leg and foot

Question 149

what is a common way the femoral nerve can be damaged? what symptoms are associated?

Answer 149

damaged in the abdomen by an abscess of the psoas major or pelvic neoplam

patients experience weakness in flexion of thigh, abiliy to extend leg at knee, and diminish patellar tendon reflex

Question 150

what are examples of common ways the saphenous nerve can be damaged? what are associated symptoms?

Answer 150

during surgical procedure of the leg to remove varicose veins or great saphenous vein or lacerated as it pierces wall of adductor canal

patients experience pain and parethesia in the skin of the medial aspect of the leg and foot

Question 151

what fibers from what rami are contained in the obturator nerve?

Answer 151

contains anterior division fibers from the L2-L4 ventral rami

Question 152

what is the course of the obturator nerve and what does it innervate?

Answer 152

emerges from medial side of psoas major, crosses pelvic brim, courses anteriorly and inferiorly in the lesser pelvis to the obturator foramen then through the obturator externus into medial thigh

divides into anterior branch (passes theough adductor longus and brevis) and posterior branch (passes between adductor brevis and adductor magnus)

innervates muscles in the medial thigh (adductor longus, brevis, and magnus, gacilis, and obturator externus)… which act to adduct the thigh and assist in hip flexion

innervtes skin in the small region of the medial thigh

Question 153

where is the obturator nerve most commonly lesioned? what are the symptoms associated?

Answer 153

in the pelvis (pelvic neoplasm or pregnancy)

patients unable to adduct the thigh at hip and may have paresthesia in skin of the medial thigh

Question 154

what are the five collateral nerves of the lumbar plexus? what are their spinal nerve origins?

Answer 154

subcostal nerve (T12)

iliohypogastric nerve (T12-L1)

ilioinguinal nerve (L1)

genitofemoral nerve (L1, L2)

lateral femoral cutaneous nerve (L2, L3)

Question 155

what is the path of the subcostal nerve and what does it innervate?

Answer 155

passes between the psoas major and quadratus lumborum muscles inferior to the 12th rib

innervates abdominal muscles and overlying skin of the lateral and anterior abdominal wall

Question 156

what is the path of the iliohypogastric nerve and what does it innervate?

Answer 156

emerges between the psoas and quadratus lumborum muscles inferior to the subcostal nerve

innervates abdominal mucles and skin of the inguinal and hypogastric regions of the lateral and anterior abdominal wall

Question 157

what is the path of the ilioinguinal nerve and what does it innervate?

Answer 157

courses inferior to the iliohypogastric nerve

pierces the inguinal canal and passes trhough the superficial inguinal ring to innervate the skin of the medial thigh, and labium majus or anterior aspect of the scrotum

above the superificlal inguinal ring it will innervate the abdominal muscles and skin of the inguinal and hypogastric regions of the lateral and anterior abdominal wall

Question 158

what is the path of the genitofemoral nerve and what does it innervate?

Answer 158

courses through and then anterior to the psosas major muscle

divides into a femoral branch: passes posterior to the inguinal ligament and innervates skin of the medial thigh, and a genital branch: enters inguinal canal through the deep inguinal ring and innervates the cremasteric muscle

Question 159

what is the path of the lateral femoral cutaneous nerve and what does it innervate?

Answer 159

emerges lateral to the psoas major muscle then crosses the iliacus to reach the ASIS then descends into the lateral thigh after passing posterior to the inguinal ligament

innervates anterolateral thigh

Question 160

what is a common site/cause of lateral femoral cutaneous nerve lesions and what are the associated symptoms?

Answer 160

may be compressed as it passes posterior to the lateral part of the inguinal ligament just medial to the ASIS (meralgia paresthetica)

pain and paresthesia in the anterolateral thigh

Question 161

What are the terminal nerves of the lumbosacral plexus and what are their spinal cord origins?

Answer 161

superior gluteal nerve (posteror division fibers from L4, L5, S1)

inferior gluteal nerve (posterior division fibers from L5, S1, S2)

tibial nerve (anterior division fibers from L4, L5, S1-S3)

common fibular/peroneal nerve (posterior division fibers from L4, L5, S1, S2)

superficial fibular nerve (L4, L5, S1)

deep fibular nerve (L5, S1, S2)

Question 162

what is the course of the superior gluteal nerve and what does it innervate?

Answer 162

enters gluteal region with the superior gluteal artery by passing through the greater sciatic foramen superior to the piriformis muscle

innervates the gluteus medius, gluteus minimus, and tensor fasciae latae muscles

Question 163

what are symptoms associated with a superior gluteal nerve lesion?

Answer 163

• weakness in ability to abduct the thigh at the hip
• waddling or Trendelendburg gait in which pelvis sags on side opposite the nerve lesion during unsupported stage of walk

Question 164

what is the course of the inferior gluteal nerve and what does it innervate?

Answer 164

enters gluteal region by passin through the greater sciatic foramen inferior to the piriformis muscle

innervates the gluteus maximus

Question 165

what symptoms are associated with an inferior gluteal nerve lesion?

Answer 165

• weakness in ability to laterally rotate and extend the thigh at the hip
• difficulty climbing stairs or rising from a chair due to difficulty extending thigh from a flexed position
• gluteus maximus gait- thrust their torso posteriorly in an attempt to coutract the weakness of the gluteus maximus

Question 166

what is the course of the tibial nerve? what does it branch into and where?

Answer 166

enters gluteal region with common fibular nerve in the sciatic nerve by passing through the greater sciatic foramen inferior to the piriformis

courses through posterior thigh deep to hamstring and separates from common fibular at superior border of the popliteal fossa

then courses in the posterior part of the leg with the posterior artery and then passes thorugh the tarsal tunnel and into th sole of the foot after coursing behind the medial malleolus

divides into the medial and lateral plantar nerves distal to the tarsal tunnel

Question 167

what does the tibial nerve innervate in general?

Answer 167

muscles in the posterior thigh, posterior leg and plantar foot

Question 168

what does the medial plantar nerve innervate?

Answer 168

medial plantar nerve (L5, S1, S2) innervates 4 muscles in the sole of the foot: flexor digitorum brevis, flexor hallucis brevis, abductor hallucis, first lumbrical; common and digital plantar branches innervate skin of the medial side of the sole of the foot and medial 3 1/2 digits
- similar to median nerve in hand

Question 169

what does the lateral plantar nerve innervate?

Answer 169

lateral plantar nerve (L5, S1, S2) innervates the rest of the intrinsic foot muscles (quadratus plantae, flexor digiti minimi brevis for toe 5, lumbricals II-IV, interrossei, dorsal interossi, abductor digiti minimi, adductor halluscis, plantar interossi); common and digital plantar branches innervate the skin of the alteral side of the sole of the foot and lateral 1 1/2 digits
- similar to ulnar nerve of the hand

Question 170

what are common causes of sciatic nerve lesions?

Answer 170

• susceptible to damage from an intramuscular injection in the lower medial quadrant of the gluteus maximus muscle
• compressed from posterior dislocation of the femur
• L5 and S1 roots of the sciatic nerve compressed by intervertebral disk herniations

Question 171

where are common sites for tibial nerve lesions and what are symptoms associated?

Answer 171

• in the gluteal region–>weakness in ability to flex leg at the knee and plantar flex at the ankle
• compressed at the ankle as it courses through the tarsal tunnel adjacent to the medial malleolus (tarsal tunnel syndrome)–>pain and parethesia in the sole of the foot

Question 172

what is the course of the fibular nerve and what does it innervate?

Answer 172

emerges from the pelvis with the tibial nerve inferior to the piriformis muscle in sciatic nerve into the posterior thigh

innervates the short head of the biceps femoris in posterior thigh then separates from the tibial at the superior border of the popliteal fossa

courses laterall along the tendon of the biceps femoris and spiral around the neck of the fibula into the lateral leg

enters the fibularis longus muscle and divides into the superficial and deep fibular nerves

Question 173

where/how is the common fibular nerve commonly lesioned and what are associated symptoms?

Answer 173

frequently lesioned in the lower leg such as when it passes around the neck of the fibula

• footdrop from loss of dorsiflexion at the ankle and loss of eversion
• pain and parethesi in the lateral leg and dorsum of the foot
• with footdrop, may also have steppage gait- raise affected leg high off the ground and foot slaps ground when walking

piriformis syndrome: nerve compressed by piriformis when it passes through it rather than anterior to it with the tibial nerve

Question 174

what is the course of the superficial fibular nerve and what does it innervate?

Answer 174

innervates the fibularis longus and brevis muscles in the lateral leg

emerges from distal third of lateral leg to innervate skin of the lateral leg and dorsum of the foot (except for the first dorsal webbed space between the great toe and second toe)

Question 175

where is a common site of supericial fibular nerve lesion and what are associated symptoms?

Answer 175

lesioned as the nerve emerges from the lateral compartment of the leg

pain and parethesia in the dorsal aspect of the foot

Question 176

what is the course of the deep fibular nerve and what does it innervate?

Answer 176

courses through the fibularis longus muscle and anterior compartment of the leg with the anterior tibial artery

innervates muscles in the anterior compartment of the leg (tibialis anterior, extensor hallucis longus, extensor digitorum longus, peroneus teritius muscles)

innervates muscles in dorsum of the foot (extensor digitorum brevis and extensor hallucis brevis muscles)

skin of the webbed space between the great toe and second toe

Question 177

where is a common site of deep fibular nerve lesion and what are associated symptoms?

Answer 177

compressed in the anterior compartment of the leg

footdrop and paresthesia in the skin of the webbed space between the great toe and second toe

Question 178

what are the collateral nerves of the lumbosacral plexus and their origins?

Answer 178

sural nerve (contributons from tibial and common fibular nerves), nerve to quadratus femoris muscle (L4, L5, S1), nerve to obturator internus muscle (L5, S1, S2), posterior femoral cutaneous nerve (anterior and posterior division fibers from S1-S3), nerve to piriformis muscle (S1-S2), perforating cutaneous nerve (S2-S3)

Question 179

what is the course of the sural nerve and what does it innervate?

Answer 179

innervates the skin of the posterior leg and lateral foot

courses with the small saphenous vein in the posterior leg

Question 180

what is the course of the nerve to the quadratus femoris muscle and what does it innervate?

Answer 180

enters the gluteal region after passing through the greater sciatic foramen

innervates the quadratus femoris (duh) and inferior gemellus

Question 181

what is the course of the nerve to the obturator internus muscle and what does it innervate?

Answer 181

enters the gluteal region after passing through the greater sciatic foramen and innervates the superior gemellus

crosses the ischial spine and through the lesser sciatic foramen to innervate the obturator internus (duh)

Question 182

what does the posterior femoral cutaneous nerve innervate?

Answer 182

skin of the posterior thigh and upper calf

Question 183

where does the nerve to the piriformis muscle arise from and what does it innervate?

Answer 183

ventral rami of S1 and S2

innervates the piriformis muscle (duh)

Question 184

where does the perforating cutaneous nerve arise form and what does it innervate?

Answer 184

ventral rami of S2 and S3

innervates skin covering the ischioanal fossa and gluteal region near the anal canal

Question 185

what is the only branch of the lumbosacral plexus to contain both anterior division (S2, S3) and posterior division (S1, S2) fibers?

Answer 185

posterior femoral cutaneous nerve

Question 186

weakness in ability to dorsiflex the foot and altered sensation in skin between the great toe and second toe is caused by lesion in what nerve?

Answer 186

deep fibular/peroneal nerve

Question 187

altered sensation in skin covering the great saphenous vein in the leg is caused by a lesion in what nerve?

Answer 187

femoral nerve

Question 188

weakness in ability to abduct thigh at the hip is caused by lesion in what nerve?

Answer 188

superior gluteal nerve

Question 189

a lesion in what nerve would cause weakness of muscles in ability to evert foot and altered sensation in the skin of the dorsal aspect of the foot, but leave ability to extend toes intact?

Answer 189

superficial fibular/peroneal nerve

Question 190

a lesion in what nerve would cause weakness in ability to extend thigh at the hip when arising from a chair and difficulty walking up stairs, but leaves cutaneous sensation intact?

Answer 190

inferior gluteal nerve

Question 191

if a patient develops tarsal tunnel syndrome and has weakness in the ability to flex the great toe, what nerve may be lesioned?

Answer 191

tibial nerve

Question 192

when a limb is off the ground during gait, and a patient experiences lateral pelvic tilt toward the unsupported side, what nerve is most likely lesioned?

Answer 192

superior gluteal nerve (gluteus minimus and medius)

Question 193

a ballet dancer can no longer stand on her “tip toes.” what nerve may be lesioned?

Answer 193

tibial nerve

(toe flexors)

*TIP TOES: Tibial Inverts and Plantarflexes allowing one to stand on TOES

Question 194

weakness in ability to adduct the thigh at the hip is most likely caused by a lesion in what nerve?

Answer 194

obturator nerve (adductors, gracilis)

Question 195

a lesion in what nerve would be most likely to cause an inability to flex the thigh at the hip and extend the leg at the knee?

Answer 195

femoral nerve (flexion of femur: rectus femoris, sartorius, pectineus; extension of tibia and fibula: quadriceps femoris)

Question 196

A football player suffers trauma to the lateral part of the leg just distal to the head of the fibula and a nerve is lesioned. What might the patient experience?

A. weakness in ability to plantar flex the foot
B. loss of ability to invert the foot
C. altered sensation in the skin of the medial aspect of the leg
D. altered sensation in the skin of the dorsal aspect of the foot
E. weakened ability to flex the toes

Answer 196

Lesion to the common fibular nerve–>

result in footdrop and altered sensation in the skin of the dorsal aspect of the foot: D

Question 197

An elderly woman who suffers from osteoporosis falls and “breaks her hip.” The orthopedic surgeon recommends that the proximal part of the femur be replaced with a prosthesis because of the likelihood of avascular necrosis of the head of the femur.

What artery supplying the neck and head of the femur might have been lacerated by the fracture?

A. inferior gluteal artery
B. medial circumflex femoral artery
C. pudendal artery
D. profunda femoral artery
E. obturator artery

Answer 197

B. this is the main source of arterial blood supply to the head and neck of the femur

the profunda femoral artery (a branch of the femoral artery which is a branch of the external iliac artery) will give rise to the lateral and medial circumflex arteries that supply the thigh, head and neck of femur, and the hip joint

Question 198

A traumatic injury to the lateral aspect of a patient’s knee tears several structures at the knee joint. An examination reveals a positive anterior drawer sign and a clicking sound when the patient attends to extend the leg at the knee.

Of the following structures, which one was most likely spared from being stretched or torn in this knee injury?

A. medial meniscus
B. tibial collateral ligament
C. fibular collateral ligament
D. anterior cruciate ligament
E. tendon of the sartorius muscle

Answer 198

A lateral blow to the knee will usually injure the terrible triad: ACL, MCL/tibial collateral ligament, medial meniscus

will also tear tendons that cross the medial aspectr of the joint such as the sartorius

least likely, is C which is on the lateral side of the joint

Question 199

A health care worker inadvertently administers an injection to the gluteal region that results in a lesion to a nerve. The patient begins to walk with an altered gait. Upon raising the left foot off the ground during gait, the patient leans to the right, and when standing on the right foot without leaning, the left buttock seems to sag.

what muscle might have been weakened by the nerve lesion?

A. gluteus maximus
B. gluteus medius
C. piriformis
D. semitendinosus
E. quadratus femoris

Answer 199

B

lesion would be the to superior gluteal nerve

• weakness in ability to abduct thigh at hip and keep pelvis level during gait
• waddling/Trendelenburg gait - pelvis sags on side of unsupported limb because of weakness of gluteus medius muscle

Question 200

A cross-country runner begins to experience leg and foot pain during and after training for an upcoming season. The pain radiates from the anterolateral leg into the dorsal aspect of the foot. Dorsiflexion and extension of the toes are performed only with pain. The leg appears to be swollen in the area of the pain.

Which of the following arteries may have been compressed by the swelling?

A. popliteal artery
B. anterior tibial artery
C. posterior tibial artery
D. peroneal artery
E. medial plantar artery

Answer 200

B

courses through the anterior comparment of the leg

Question 201

A 56-year-old man develops numbness and tingling in the lower limb followed by progressive muscle weakness. You suspect the main’s peripheral neuropathy may be a side effect of a drug he is taking. You order a biopsy of a cutaneous nerve in the posterior leg that accompanies the small saphenous vein. Which of the following nerves was biopsied?

A. tibial
B. superficial fibular
C. sural
D. saphenous
E. deep fibular

Answer 201

C

sural nerve is a cutaneous nerve that innervates the posterior leg

the saphenous nerve supplies the medial leg

superficial fibular supplies the lateral leg

tibial and deep fibular nerves do not have cutaneous branches in the leg