Orthopaedics

Question 1

An 18yo football player is seen in the mergency ward with severe knee pain incurred after being hit by a tackler while running. which of the following findings on exam is most sensitive for anterior cruciate ligament injury?

a. excessive valgus laxity of the knee
b. excess varus laxity of the knee
c. locked knee
d. positive lachman test
e. positive posterior drawer test

Answer 1

D

lachman = sensitive & relaible clinical test

posterior drawer test = PCL injury
“locked knee” = displaced meniscal tear; prevents full extension of the knee
excess valgus laxity = MCL injury
excess varus laxity = LCL injury

Question 2

34yo man is extricated from an automobile after a MVA. the pt has an obvious deformity of his R thigh consistent with a femur fracture. upon closer exam of the R thigh, there is bone visible through an open wound. which of the following is the most appropriate management of his open femur fracture?

a. IV antibiotics and cast / splint placement
b. IV antibiotics and internal/external fixation
c. early irrigation & debridement, IV abx & cast / split placement.
d. early irrigation & debridement, IV abx & external/internal fixation
e. early irrigation & debridement, IV abx & compartment decompression, and internal/external fixation

Answer 2

E

Open fracture = early irrigation & debridement (w/ repeats 48-72h)
muscle damage in open fracture = fasciotomies performed during debridement
internal/external fixation –> greater access to wound care; for stabilization.

wound coverage usually accomplished w/in 1 wk of injury

Question 3

65yo man presents with acute onset of pain, swelling and erythema of the L knee. he denies previous episodes or trauma to the knee. the diffdx includes septic arthritis and gout. which ofthe following is the best study to differentiate b/w gout and septic arthritis?

a. WBC
b. xray of the knee
c. MRI of the knee
d. bone scan
e. evaluation of synovial fluid aspirate

Answer 3

E

synovial fluid analysis = best to diagnose

Question 4

while playing with his children, a 44yo man falls and lands on his R shoulder. there is immediate pain and deformity. in an uncomplicated dislocation of the glenohumeral joint, the humeral head usually dislocates primarily in which of the following directions?

a. anteriorly
b. superiorly
c. posteriorly
d. laterally
e. medially

Answer 4

A

many more tendons protecting arm posteriorly

Posterior = teres minor, infraspinatous, long head of triceps

Anteriorly = pectoralis major, long head of biceps

Question 5

29yo construction worker fell 15 ft from a roof and broke his R humerus in the distal half of the humeral shaft, as depicted in the accompanying radiograph: with proximal portion of humerus displaced posteriorly. given his injury, which of the following nerves is most at risk?

a. median nerve
b. radial nerve
c. posterior interosseus nerve
d. ulnar nerve
e. ascending circumflex brachial nerve

Answer 5

B

in the radial groove - radial nerve as it courses into the forearm compartment; high risk of injury

Question 6

in a failed suicide gesture, a depressed student severs her radial nerve at the wrist. which of the following is her expected disability?

a. loss of ability to extend the wrist
b. loss of ability to flex the wrist
c. wasting of the intrinsic muscles of the hand
d. sensory loss over the thenar pad and the thumb web
e. palmar insensitivity

Answer 6

D

distal radial nerve = sensory to dorsum of hand from radial aspect of 1st-4th digits; sensation of thenar pad & thumb web
proximal radial nerve = extension of wrist and digits, forearm supination

Question 7

after being injured by a bull on his mother’s farm, a young man is placed in a cast for a supracondylar fracture of his humerus. a few h later he begins to experience intense pain, swelling, and weakness in the ipsilateral hand. pulses are normal in the bl upper extremities. which of the following is the most appropriate initial management of this pt?

a. observation
b. repeat imaging of the humerus
c. elevation of the extremity
d. removal of the cast
e. surgical decompression (fasciotomy)

Answer 7

D

compression syndrome = increasing pressures in fascial compartments; compromise of capillary blood flow

1) loss of O2 delivery to tissues from increased capillary permeability.
2) venous and lymphatic flow compromised –> further edema
3) arterial flow compromised –> LATE FINDING = pulse changes

Tx

1) remove the cast
2) surgical fasciotomy

Question 8

39yo man presents with an isolated fracture of the tibia after being hit in the leg with a car. the pt is stable and a radiograph of the leg shows a tibial fracture with severe dislocation. which of the following is the most appropriate management of the fracture.

a. closed reduction & application of a long leg cast
b. intramedullary nailing
c. surgical fixation with unreamed nailing
d. external fixation
e. plate fixation

Answer 8

B

long, strong bone

stable pt; severe tibial shaft fracture = surgical fixation with intramedullary nailing (reamed cannulated nails)

high energy trauma + polytrauma (significant soft tissue & vascular injuries) = external fixation

periarticular injuries too proximal / distal for intramedullary nailing = plate fixation of tibial fractures

tibial shaft fractures of minor severity & dislocation = closed treatment

CONS of
- unreamed nailing = nonunion; malunion

Question 9

for each description, select the type of fracture or dislocation with which it is most likely to be associated.
a. navicular (scaphoid) fracture
b. monteggia deformity
c. night stick fracture
d. anterior shoulder dislocation
e. fracture of the scapula
a pt presents with pain in the shoulder after a fall. on exam, the shoulder internally rotated.

Answer 9

D

tx = closed reducgtion + sling

Question 10

for each description, select the type of fracture or dislocation with which it is most likely to be associated.
a. navicular (scaphoid) fracture
b. monteggia deformity
c. night stick fracture
d. anterior shoulder dislocation
e. fracture of the scapula
a pt has tenderness over the forearm after being attacked by gang members with baseball bats

Answer 10

C

night stick fracture = of ulnar shaft that result from direct blow to the ulnar forearm by a club or night stick

tx = cast

Question 11

for each description, select the type of fracture or dislocation with which it is most likely to be associated.
a. navicular (scaphoid) fracture
b. monteggia deformity
c. night stick fracture
d. anterior shoulder dislocation
e. fracture of the scapula
30yo cyclist falls and injures her forearm. the radial head is dislocated and the proximal third of the ulna is fractured

Answer 11

B

Montaggia ddeformity = dislocation of radial head + fracture of proximal 1/3 of ulna

tx = internal fixation of ulna + closed reduction of radial head

late complications = heterotopic ossification and redislocation of the radial head.

Question 12

for each description, select the type of fracture or dislocation with which it is most likely to be associated.
a. navicular (scaphoid) fracture
b. monteggia deformity
c. night stick fracture
d. anterior shoulder dislocation
e. fracture of the scapula
a pt has tenderness in the anatomical snuffbox

Answer 12

A

fall on outstretched hand –> fracture of navicular (scaphoid) bone
= tendernesss to palpation at anatomic snuffbox

tx = immobilization with thumb spica splint

Question 13

for each description, select the type of bone disease with which it is most likely to be associated.
a. osteogenesis imperfecta
b. osteopetrosis
c. osteitis fibrosa cystica
d. osteomalacia
e. osteitis deformans (Paget’s disease)
a pt with elevated parathyroid hormone levels presents with brown tumors in the long bones

Answer 13

C

long term effect of hyperPTHism = increased bone turnover

high alk phos
brown / osteoclastic tumors & bone cysts

tx = parathyroidectomy

Question 14

for each description, select the type of bone disease with which it is most likely to be associated.
a. osteogenesis imperfecta
b. osteopetrosis
c. osteitis fibrosa cystica
d. osteomalacia
e. osteitis deformans (Paget’s disease)
a pt with chronic renal failure presents with skeletal deformity and pain

Answer 14

D

due to tertiary hyperparathyroidism
low Ca
high PO4.

osteomalacia = low bone turnover; skeletal deformity, fratures, pain

Question 15

for each description, select the type of bone disease with which it is most likely to be associated.
a. osteogenesis imperfecta
b. osteopetrosis
c. osteitis fibrosa cystica
d. osteomalacia
e. osteitis deformans (Paget’s disease)
a genetically determined disorder in the structure or processing of type I collagen may require your pt to wear various orthoses to protect himself.

Answer 15

A

blue sclera

brittle bones (type 1 collagen)
osteopenia, low uscle mass, heria

Vikings - Ivar the boneless

Question 16

for each description, select the type of bone disease with which it is most likely to be associated.
a. osteogenesis imperfecta
b. osteopetrosis
c. osteitis fibrosa cystica
d. osteomalacia
e. osteitis deformans (Paget’s disease)
a pt presents with cortical thickening and cortical expansion of teh bone with sclerotic mass

Answer 16

E

osteitis deformans (Paget’s) = large, abnormal osteoclasts; increased body resorption = local lysis of bone –> rapid healing process –> sclerosis, cortical thickening, cortical expansion of the boen on radiographs

NOT osteopetrosis = increased density of bone (not sclerosis)

Question 17

for each description, select the type of lesion with which it is most likely to be associated.
a. osteoid osteoma
b. osteoblastoma
c. osteosarcoma
d. chondrosarcoma
e. ewing sarcoma
11yo boy presents with pain in his R leg. a radiograph shows a circumscribed, densely sclerotic mass limited to the metaphysis of the lower femur

Answer 17

C

sclerotic

osteosarcoma = most common bone malignancy in children; esp. in long bones. Densely sclerotic mass
tx = wide surgical excision + adjuvant radiation / chemotherapy

Question 18

for each description, select the type of lesion with which it is most likely to be associated.
a. osteoid osteoma
b. osteoblastoma
c. osteosarcoma
d. chondrosarcoma
e. ewing sarcoma
9yo boy presents with severe pain in the L femur. the pain is relieved by aspirin. on plain film, a 0.5cm lucent lesion, which is surrounded by marked reactive sclerosis, is seen.

Answer 18

A

“relieved by aspirin”

Osteoid osteoma = severe pain, relieved by aspirin. small lucency (<1.5cm) within bone surrounded by reactive sclerosis.
tx = surgery

Question 19

for each description, select the type of lesion with which it is most likely to be associated.
a. osteoid osteoma
b. osteoblastoma
c. osteosarcoma
d. chondrosarcoma
e. ewing sarcoma
12yo boy complains of pain in his L leg that is worse at night. he has been experiencing fevers and also has a 9lb weight loss. xray demonstrates an aggressive lesion with a permeative pattern of bone lysis and periosteal reaction. there is an associated large soft tissue mas as well. pathology demonstrates the tumor to be of a round cell type.

Answer 19

E

Ewing sarcoma = round cell-type tumor. highly malignant; in long bones. Permeative pattern of bone lysis & periosteal reaction + soft tissue mass. esp. at night + fever, weight loss
tx= radiation & systemic chemotherapy.

Question 20

6yo boy is brought into the ED by his mother for walking with a limp for several weeks. on exam, the pt has tenderness over his R thigh without evidence of external trauma. an xray fo the pelvis shows a R femoral head that is small and denser than normal. which of the following is the most likely diagnosis?a

a. slipped capital femoral epiphysis (SCFE)
b. Legg-calve-perthes (LCP) disease
c. dysplasia of the hip
d. talipes equinovarus
e. bount disease

Answer 20

B

Legg–Calvé–Perthes disease

• boys age 2-12
• bilateral in 10-20%
• Patho –> period of ischemia in the proximal femoral epiphysis followed by revascularization
• Hx = limp & pain in the groin, thigh, or knee

Question 21

what is the most appropriate treatment for an elderly pt with a displaced femoral neck fracture?

a. traction
b. hemiarthroplasty
c. reduction and pinning
d. bed rest
e. bracing

Answer 21

C

Femoral neck displacement - reduction (open/closed)

Question 22

The following are findings in late stage osteoarthritis except:

a. subchondral arthritis
b. osteophyte formatio
c. joint space narrowing
d. subchondral cystic changes
e. fracture

Answer 22

E

not a weakening of the bones = just a degradastion of the cartilage

Question 23

you respond to the trauma bay to evaluate a 30yo pt for a b/l femur fracture after an MVC. your primary survey reveals an intubated pt with a palpable pulse. his vital signs are pulse 130, BP 80/40, and controlled RR. he does not have a foley in place because of his pelvic injury. the first step should be

a. obtain consent for intramedullary nailing of his femur fractures
b. placement of b/l femoral traction pins
c. IV fluid replacement of 2000cc of Lactated ringer’s
d. transfer the pt to the ICU and initiate phenylephrine drip to manage his hypotension
e. placement of b/l long leg spica casts

Answer 23

C

hypotensive = give fluids first. he could be hemorrhaging occultly

Question 24

a pt arrives to the ED after being struck by a car and sustain an open both bone (radius & ulna) fracture with a 1cm laceration. what is the most appropriate initial management of the pt?

a. prompt reduction of the protruding bone back into the skin and place the arm in a long arm cast
b. administration of cefazolin and tetanus toxoid booster
c. administration of pip/tazo to cover gram negatives
d. administration of hydromorphone by mouth
e. placement of external fixator in the ED.

Answer 24

B

management of open fracture

1) IV Abx, tetanus toxoid
2) if contaminated = give anaerobic coverage

Question 25

a pt presents with a large posterolateral L5-S1 disc herniation placing pressure on the S1 nerve root. what are the likely exam findings.

a. weak ankle dorsiflexion with a babinski sign
b. weak extensor hallucis lungus with a positive femoral tension sign
c. weak ankle plantarflexion with an absent achilles reflex
d. overflow incontinence and bowel incontinence
e. b/l lower extremity weakness with hyperreflexive patellar responses

Answer 25

C

weakness / numbness in the lateral leg.

L5 = dorsiflexion
S1 = lateral leg; plantarflexion

Question 26

which of the following rotator cuff muscles originates from the anterior scapula

a. supraspinatus
b. infraspinatous
c. subscapularis
d. teres minor
e. anterior scalene

Answer 26

C. attaches to the medial portion of the humerus

anterior scalene originates transverse processes of C3-C4 vertebrae; inserts on 1st rib.

Question 27

alkaptonuria pathophysiology

sxs

Answer 27

AR –> buildup of homocysteine

• arthralgia –> toxic to cartilage (black)
• black pigment in eyes
• urine turns black if left out

Question 28

complex regional pain syndrome

• cause
• sxs
• mgmt

Answer 28

• cause = trauma (fracture, crush injury, sprain, surgery) –> d/t tissue / neurogenic inflammation / disruption in central pain signaling
• sxs = pain to extremity that is out of proportion in time / severity to normal course of injury; sensory changes, motor impairments, autonommic dysfunction in the extremtiy, trophic changes (of hair / nail)
• management
  1) Vit C, NSAIDS
  2) steroids; gabapentin / TCS
  3) sympathetic nerve block; sympathectomy (diagnosis by therapy)

Question 29

Volkmann contracture is a complication of what? pathophysiology

Answer 29

• -> d/t supracondylar / forearm fracture (ex. supracondylar fracture)
• -> vascular injury & swelling –> COMPARTMENT SYNDROME –> ischemia & ifarction to superficial & deep flexor muscles –> fibrosis & contracture

Question 30

how can volkmann contracture be prevented?

Answer 30

fasciotomy to reverse compartment syndrome