Answer to x-ray quiz of the day - 2

The correct answer is d: Osteochondroma

Explanation: Osteochondromas have a characteristic radiographic appearance. The lesion is a surface tumor and the medullary cavity of the normal bone flows into the osteochondroma. Some authors call this "cortical sharing." Osteochondromas may have a well defined stalk (pedunculated osteochondroma) or they may have a broad base as in this case (sessile osteochondroma). This diagnosis can be made with the plain radiographs without histologic confirmation.

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X-ray quiz of the day - 2

A 16-year-old girl has a painless bump behind her knee. However, she does have pain if she her leg is hit while playing soccer. On physical examination there is a firm lump behind the knee. A plain radiograph of the knee is shown.

The most likely diagnosis based on the history, physical examination and plain radiograph is:

a) High-grade intramedullary osteosarcoma
b) Parosteal osteosarcoma
c) Periosteal osteosarcoma
d) Osteochondroma
e) Periosteal chondroma

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Answer to X-ray quiz of the day - 1

The correct answer is b

The patient has an L5/S1 spondylysis with a grade 1 spondylolisthesis. This patient has undergone a sufficient attempt at conservative management with continued unrelenting low back pain. The next most appropriate step in the management of this condition is a posterolateral fusion at the L5/S1 level with autologous bone graft.

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X-ray quiz of the day - 1

A 22-year-old woman sustained an injury to her low back 1 year ago while playing rugby. She now complains of excruciating low back pain with numbness and tingling into her left buttock. This pain is affecting her daily living activities. The patient underwent 6 months of conservative management consisting of restriction of activities, physical therapy, and anti-inflammatory medication with little relief. Based on the image below, the next appropriate step in the management of this patient is:

a) Continued conservative management
b) Posterolateral fusion at the L5/S1 level with bone graft
c) Laminectomy at the L2/L3 level
d) Laminectomy at the L3/L4 level
e) Diskectomy at the L3/L4 level

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MCQs: Spine Trauma - General

1. The American Spinal Injury Association (ASIA) has developed a classification of spinal cord injuries. Using this classification system, an Asia C injury is best described as:

a) Complete motor loss with incomplete sensation
b) Complete motor loss with complete sensation loss
c) Incomplete motor loss with some preservation of motor function with groups with less then grade 3 strength
d) Incomplete motor loss with normal bladder function
e) Incomplete motor loss with 4+ strength and patchy sensation


2. Which of the following statements is true regarding neurogenic shock:

a) Neurogenic shock is due to severe blood loss associated with a spinal cord injury.
b) Neurogenic shock can be diagnosed when there is hypotension and tachycardia.
c) Neurogenic shock is due to increased parasympathetic tone.
d) Neurogenic shock is best treated with judicious use of fluids and vasopressors.
e) Neurogenic shock is a sign of an incomplete spinal cord injury.

Answers

1. C

Asia C is an incomplete spinal cord injury with reservation of motor function with <>

2. d

Neurogenic shock is present when there is a spinal cord injury interrupting sympathetic tone to the heart and blood vessels, and it is heralded by bradycardia and hypotension. It is important to maintain a reasonable blood pressure to prevent further damage to the spinal cord due to ischemia. In the absence of significant blood loss from another source, neurogenic shock must be treated with vasopressor medication and atropine. Severe neurogenic shock may require cardiac pacing. Fluids must be used carefully as overzealous use of fluid resuscitation can result in pulmonary edema.

MCQ: Diseases of the Back

1. Weakness of the extensor hallucis longus is evidence of nerve root compression at what level?

a. L2
b. L3
c. L4
d. L5
e. S1


2. Spondylolysis (pars defect) is most widely believed to be caused by what?

a. A congenital defect in the pars
b. An acute traumatic defect in the pars
c. A stress fracture of the pars
d. A benign neoplasm involving the pars
e. None of the above


3. Cauda equina compression (CEC) syndrome is most typically manifested by:

a. Foot-drop
b. Severe back pain
c. Parasthesias in a nonanatomic distribution
d. Urinary retention
e. Priapism


4. A sequestered disk herniation refers to:

a) Bulging of the nucleus through a weakened annulus
b) Rupture of the nucleus through the annulus
c) Rupture of the nucleus through the annulus and the posterior longitudinal ligament
d) Rupture of the nucleus through the posterior longitudinal ligament
e) Separation of a herniated fragment from the disk


5. A 30-year-old man underwent an anterior lumbar discectomy and fusion at L4-L5 and L5-S1 through an anterior retroperitoneal approach 1 month ago. He now reports that he is unable to obtain and maintain an erection. The most likely cause of this condition is:

a) Disruption of the sympathetic nerves during anterior lumbar exposure
b) Traction on the parasympathetic nerve at the L4-L5 level
c) Not related to the surgical dissection
d) Injury to the pudendal nerves in the anterior sacral region during dissection at the L5-S1 level
e) Sexual dysfunction secondary to retrograde ejaculation


6. Which of the following antibiotics would not be useful in staphylococcal vertebral osteomyelitis:

a. Cefuroxime
b. Nafcillin
c. Cefazolin
d. Ciprofloxicin
e. Tobramycin


7. Which of the following is the most common source of infection in vertebral osteomyelitis:

a. Trauma
b. Iatrogenic
c. Hematogenous spread
d. Spontaneous
e. Unknown mechanism

Answers

1. d
The extensor hallucis longus is innervated by L5; weakness of this muscle would be evidence of an L5 radiculopathy.


2. c
Spondylolysis is believed to be a stress or fatigue fracture of the pars interarticularis occurring because of repetitive shear stresses from repetitive hyperextension in individuals with a hereditary predisposition. It occurs most commonly at L5, is more common in boys than in girls and in athletes, particularly gymnasts.


3. d
Urinary retention results from lower motor neuron bladder dysfunction seen in cauda equina compression (CEC) syndrome. Patients with CEC syndrome may also present with severe back pain, saddle anesthesia, pain down the back of lower extremities, or even foot drop, but the most typical and most important manifestation is bladder dysfunction.


4. e
A sequestered herniation is a separation of a herniated fragment from the disk from which it came.


5. c

Sexual dysfunction is a common condition after extensive anterior lumbar surgical dissection. Erectile dysfunction is often nonorganic but may be related to parasympathetic injury. The parasympathetic nerves are deep in the pelvis at the level of S2-S3 and S3-S4 and are not usually involved in the surgical field for anterior L4-L5 and L5-S1 procedures. Retrograde ejaculation is the result of injury to the sympathetic chain on the anterior surface of the major vessels crossing the L4-L5 level and at the L5-S1 interspace. Erectile function and orgasm are not affected by sympathetic injury. The pudendal nerve is primarily a somatic nerve and is not located in the surgical field.

6. e

Aminoglycosides, such as tobramycin, are active against gram-negative organisms. First- and second-generation cephalosporins are alternatives to semisynthetic penicillins that may be useful if the organism is not resistant. Ciprofloxicin has also been considered a possible alternative to penicillins against gram-positive vertebral osteomyelitis.

7. c

Hematogenous seeding from another primary source is the most common causative agent. Hematogenous spread of infections is believed to affect the spine via septic emboli in the endarteriolar circulation of segmental spinal arteries at the vertebral endplates. The majority of cases of pyogenic spondylitis begin in the subchondral, metaphyseal region of the anterior subligamentous portion of the vertebral body — the portion with the greatest arterial supply and the most anastomoses.

X-ray of the day: Knee lesion

Osteoehondritis dissecans (OCD) of the lateral femoral condyle.
AP radiograph of the knee showing a typical osteochondral lesion with a defect containing a fragment, located centrally in the femoral condyle.

Aetiology of OCD: Unknown; most commonly accepted thories are trauma, abnormal ossification within the epiphysis, ischaemia, or some combination of these.

The medial condyle is involved 85% of the time vs. 15% of the lateral condyle.

50% of loose bodies in the knee are associated with OCD.

X-ray of the day: Foot lesion

Fracture-dislocation of the Lisfranc joint after fall during jogging.
AP and oblique radiographs show small avulsion fractures between the bases of the metatarsal bones (arrows) and a slight increase in distance between the bases of the first and second metatarsal bones.





CT sections of the tarsometatarsal joints confirm the extension of the injury throughout the Lisfranc joint (ventral arrows) with multiple avulsion fractures, including one at the lateral aspect of the cuboid (horizontally oriented white arrow).

X-ray of the day: Foot lesion

Displaced fracture-dislocation of the first through fourth tarsometatarsal joints, the Lisfranc joint (arrows), and avulsion fractures between the base of second and third metatarsal bones (short arrow).

MRI of the day: Talus lesion

Osteochondral fracture of the dame of the talus, osteochondritis dissecans. T2-weighted caranal, gradient echo MR image of an ankle in a young woman one month after injury to the ankle. The cartilage has high signal intensity. The osteochondral lesion appears at the medial aspect of the dame of the talus (arrow). The lesion is covered by cartilage.

X-ray of the day: Traumatic lesion of the ankle

Pronation-external rotation injury, stage IV of the ankle:
AP and lateral radiographs reveal a fracture of the fibula at a high level and a small avulsion fracture of the posterior lip of the tibia (arrow). According to the staging, the injury includes complete tear of the deltoid ligament of the medial malleolus.

X-ray of the day: Traumatic lesion of the ankle

Supination-external rotation injury of the ankle stage IV: AP and lateral radiographs demonstrate a fracture of the distal end of the fibula and the medial malleolus as well as an avulsion fracture of the posterior lip of the tibia (arrowheads).





Postoperative radiograph after fracture reduction and fixation of this stage IV injury.

MRI of the day: Knee lesion

Tear of the medial meniscus. T2-weighted sagittal MR image of the medial portion of the femur and tibia using gradient echo technique. There is a normal low signal intensity in the anterior horn of the medial meniscus (black arrow). In the posterior horn of the meniscus a tear is seen (white arrow). V = joint effusion, B = Baker cyst.

X-ray of the day: Fracture of the lateral tibial condyle

Fracture of the lateral tibial condyle after a fall from a height. The radiograph shows displacement of fragments of a lateral condyle, but the severity of displacement cannot be assessed.


T1-weighted sagittal MRI scan of the lateral femoral and tibial condyle. Advanced displacement of osteochondral fragment (white arrows) is present. The tibiofibular joint is indicated (black arrow).

Case of the day: Hip lesion

Osteonecrosis of the femoral head after fracture of the neck. Almost nothing remains of the head, and the nail is penetrating the acetabulum.

X-ray of the day: Proximal humeral fracture in an adult

Fracture of the surgical neck of the humerus (black arrow) with moderate displacement. Soft tissue calcification is present about the greater tuberosity (white arrow).

X-ray of the day: Elbow fracture in a child

Displaced supracondylar fracture of the humerus in a child.

X-ray of the day: Elbow trauma

Traumatic hemarthrosis of the elbow joint, the fat pad sign. A joint effusion displaces the ventral as well as the dorsal fat pad (white arrowhead).

A fracture of the radial head, Salter Harris type II (white arrow), is seen.

A normal ossification centre of the olecranon is present.

X-ray of the day: Old fracture Scaphoid

Old fracture through the scaphoid with delayed union. The density of the proximal fragment is increased relative to the distal fragment and remaining carpal bones. The increased density may indicate osteonecrosis of the proximal fragment.

X-ray of the day: Fracture-dislocation of the fourth and fifth carpometacarpal joints.

Fracture-dislocation of the fourth and fifth carpometacarpal joints: AP view of the car pus reveals a small fragment between the base of the third and fourth metacarpal bones (arrow).






The lateral view reveals a dorsal fracture, which initially was overlooked (arrow).





Sagittal CT section demonstrates fracture-dislocation of the fifth carpometacarpal joint with a fracture of the dorsal lip of the hamate displaced in a proximal direction. m = fifth metaearpal, t = triquetrum, l = lunate, u = ulna, h = hamate






Pin fixation after open reduction of the injury.

X-ray of the day: "reverse Bennett fracture"

lntraarticular fracture-dislocation in the fifth carpometacarpal joint: "reverse Bennett fracture".

X-ray of the day: Bennett's fracture

Bennett injury (intraarticular fracture-dislocation of the first carpometacarpal joint). Note displacement of the dorsal fragment in a proximal direction (arrow).

X-ray of the day: Smith fracture

Fracture of the distal end of the radius of Smith type with displacement volarly (v).

X-ray of the day: Slipped distal radial epiphysis

Epiphysiolysis of the distal end of the radius with displacement in a dorsal direction, Salter-Harris type II injury.

Two years after the injury there is premature closure of the physis and severe deformity.

X-ray of the day: Colles' fracture

Fracture of the distal end of the radius (Colle's fractures), lateral view. The angulation occurs in a dorsal direction. v = volarly, d = dorsally.


Fracture of the distal end of the radius (Colle's fractures), PA view.

X-ray of the day: Bimalleolar fracture

Avulsion fracture of the medial malleolus (white arrow).
A fracture of the distal end of the fibula is observed (open arrow).

The avulsion fracture and the widening of the joint space medially indicate a serious ankle in jury (supination-external rotation injury stage IV).

X-ray of the day: Fracture of the Tibial Plateau

Diagnosis: displaced split depression (Schatzker II) fracture.

Treatment: The best treatment option is open reduction internal fixation using lag screws and a lateral buttress plate. The depressed fragment cannot be reduced by closed means using ligamentotaxis to facilitate the reduction. Bone grafting will hasten union.

X-ray of the day: Aneurysmal Bone Cyst

Findings: X-ray of the right wrist in a 13 year old female showing an expansile lytic lesion involving the metaphysis of the distal ulna. The margins are well-defined and there are multiple internal septations. There is no discrete evidence for periostitis.

Diagnosis: Aneurysmal bone cyst.

Discussion:

• Radiographic findings of aneurysmal bone cyst include an eccentric, lytic lesion, with an expanded, remodeled bony contour. Radiographs on occasion may show internal densities characteristic of chondroid matrix. In addition, internal septations are common.
  
• The appropriate treatment of an aneurysmal bone cyst include identifying its specific pre-existing lesion. Treatment is generally directed at surgical removal of the entire lesion versus curettage with bone grafting.

X-ray of the day: Galeazzi Fracture-dislocation

Findings: Fracture of the radial diaphysis at the junction of the middle and distal thirds with associated disruption of the distal radioulnar joint.

Diagnosis: Galeazzi fracture-dislocation.

N.B. This lesion is approximately three times as common as Monteggia fractures.

Treatment:

• Open reduction and internal fixation (ORIF) comprise the treatment of choice, because closed treatment is associated with a high failure rate.
• Plate and screw fixation is the treatment of choice.
• An anterior Henry approach typically provides adequate exposure of the radius fracture, with plate fixation on the flat, volar surface of the radius.
• The distal radioulnar joint injury typically results in dorsal instability; therefore, a dorsal capsulotomy may be utilized to gain access to the distal radioulnar joint if it remains dislocated after fixation of the radius. Kirschner wire fixation may be necessary to maintain reduction of the distal radioulnar joint if unstable. If the distal radioulnar joint is believed to be stable, however, postoperative plaster immobilization may suffice.
• 
  

Postoperative Management:

• If the distal radioulnar joint is stable: Early motion is recommended.
• If the distal radioulnar joint is unstable: Immobilize the forearm in supination for 4 to 6 weeks in a long arm splint or cast.
• Distal radioulnar joint pins, if needed, are removed at 6 to 8 weeks.

X-Ray of the Day - Monteggia Fracture Dislocation

Findings: Fracture of the proximal third of the ulna with associated anterior dislocation of the radial head.

Diagnosis: Monteggia fracture-dislocation (Bado type I).

Bado Classification of Monteggia fractures:

• Type I: Fracture of the proximal third of the ulna with anterior dislocation of the radial head.
• Type II: Fracture of the proximal third of the ulna with posterior dislocation of the radial head.
• Type III: Fracture of the ulnar metaphysis with lateral dislocation of the radial head.
• Type IV: Fracture of the proximal third of both radius and ulna with anterior dislocation of the radial head.

The basis of the Bado classification scheme is that the radial head dislocation is in the direction of the fracture apex.

Treatment:

• Closed reduction and casting should be reserved only for the paediatric population.
• Montegia fractures require operative treatment, with

1. Closed reduction of the radial head under anaesthesia.
2. Open reduction and internal fixation (ORIF) of the ulna shaft with a 3.5-mm dynamic compression plate (DCP) or reconstruction plate.
   

The Galeazzi fracture is a related fracture in that it involves a forearm fracture (this time the distal shaft of the radius) and is associated with dislocation of the distal radio-ulnar joint.

MCQ: Trauma - Thoracolumbar Spine

1. The fixation construct shown to provide optimal fixation of an unstable vertically displaced transforminal sacral fracture is:

a) An iliosacral screw into the S1 vertebral body
b) Iliosacral screws in S1 and S2
c) Tension band plate fixation
d) Triangular osteosynthesis
e) An iliosacral screw that traverses the S1 vertebral body and achieves purchase in the opposite iliac wing


2. The injury centre of rotation in a flexion-distraction fracture:

a) is located anterior to the centre of rotation of the spine
b) is located within the centre of rotation of the spine
c) is located posterior to the centre of rotation of the spine
d) may be located in all three of the above.


3. Which one of the following traumatic spinal fractures places the neurologic structures at greatest risk?

a) compression fracture
b) translational fracture
c) flexion-distraction fracture
d) extension-distraction fracture
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Answers

1.
Answer: d

Explanation: The term triangular osteosynthesis describes fixation constructs that involve placement of pedicle screws in the lower lumbar and the posterior ilium in conjunction with iliosacral screws. In a biomechanical study, triangular osteosynthesis was shown to be superior to iliosacral screws alone for fixation of unstable transforaminal sacral fractures.


2.
Answer: a



3.
Answer: b

Trauma - Lower Limb (2)

1. Angiography should be used in dislocations of the knee:

a) In the presence of asymmetric pulses
b) In all cases
c) With absent pulses only
d) Does not need to be used as long as Doppler pulses are audible
e) Has been replaced by magnetic resonance image scanning


2. When using the lesser trochanteric profile to assess femoral rotation, a smaller lesser trochanter compared to the uninjured side indicates:

a) External rotation deformity of the distal fragment
b) Internal rotation deformity of the distal fragment
c) A prior injury of the lesser trochanter
d) A varus deformity of the proximal segment
e) A valgus deformity of the proximal segment


3. The safest distance below the knee for placement of external fixation wires is:

A) 5 mm
B) 9 mm
C) 14 mm
D) 19 mm
E) 25 mm


4. Which of the following is not required for use of the dynamic condylar screw (DCS) in a supracondylar femur fracture

A) 4 cm of intact distal femur or easily reconstructable distal femur
B) Intact medial condyle
C) Healthy, nonosteoporotic bone
D) Intact lateral soft tissue envelope
E) Fracture without intracondylar extension


5. Clinical variables associated with a poor outcome following calcaneal fractures include all of the following except:

a) Age older than 50 years
b) Increased body weight
c) History of heavy labor
d) On workers' compensation
e) Decreased body weight



6. Which of the following tibial plateau fractures is often associated with vascular injury:

a) Schatzker type I
b) Schatzker type II
c) Schatzker type III
d) Schatzker type IV
e) Bilateral fractures


7. Which of the following is an advantage of lateral positioning over supine positioning when performing antegrade intramedullary nailing of a subtrochanteric femur fracture with an intact lesser trochanter:

a) Provides improved pulmonary ventilation
b) Eliminates valgus sag at fracture site
c) Allows faster setup and positioning
d) Provides easier alignment of the distal segment to the flexed proximal segment
e) Provides more accurate rotational alignment
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Answers

1.
Answer: a

Explanation: Some controversy exists as to the role of angiography. It is clear that if pulses are not symmetric, angiography is indicated. By the time a Doppler study is needed, pulses are not palpable and angiography should be performed anyway. The need for angiography should not be determined by absent pulses, only asymmetric pulses.

2.
Answer: b

Explanation: Because the lesser trochanter is a posteromedial structure, a smaller profile indicates that the proximal segment is internally rotated compared to the knee. Rotation of the distal fragment is independent of the position of the proximal fragment as they are not connected. A smaller lesser trochanter means the proximal femur is internally rotated; the distal fragment can be either internally or externally rotated.


3.
Answer: C

Explanation: The joint capsule reflects 14 mm below the joint line. Pins placed less than 14 mm below the knee are at risk for articular penetration. Violation of the proximal tibio-fibular joint can also lead to knee sepsis.


4.
Answer: A

Explanation: To obtain adequate fixation using a DCS, at least 4 cm of intact distal femur or easily reconstructable intracondylar femur is necessary as well as an intact medial condyle. If the device is used percutaneously without medial soft tissue stripping, then medial bone grafting is not necessary. Dynamic condylar screws are ideal fixation devices in osteoporotic bone with the use of cement augmentation. The disadvantage to this plate is that the large shoulder can sometimes be prominent on the lateral aspect of the femur.



5.
Answer: e

Explanation: Paley and associates demonstrated the clinical variables associated with a poor outcome include age older than 50 years, increased body weight, history of heavy labor, and on workers' compensation.


6.
Answer: d

Explanation:A Schatzker type IV fracture is a fracture of the medial tibial plateau and may be a split or a split depression fracture. Many of these fractures represent a medial dislocation of the knee that has been reduced by the time the radiographs are taken. It is not the fracture of the medial plateau that gives this fracture its bad prognosis, but the associated injuries to the popliteal artery and peroneal nerve, as well as injuries to the collateral and cruciate ligaments. The arterial injury may be a rupture or only an intimal tear. Because of the frequence of associated popliteal artery injuries, whenever this lesion is recognized patients should be considered for an arteriogram to evaluate the artery and prevent and intraoperative or postoperative thrombosis.


7.
Answer: d

Explanation:

Subtrochanteric fractures can pose challenges in reduction due to the muscle attachments proximal and distal to the fragment. The gluteus medius and gluteus minimus attach to the greater trochanter and abduct the proximal fragment. The iliopsoas attaches to the lesser trochanter, flexing and externally rotating the proximal fragment. In the lateral position, it may be easier to align the distal fragment with the flexed proximal fragment. In the supine position, it may be necessary to place a Schantz pin in the proximal fragment to counteract the deforming forces acting on the proximal fragment.

Pulmonary ventilation is better in the supine position. In the lateral position, you must be careful to avoid valgus sag at the fracture site. Careful attention to correct rotational alignment is necessary in both the supine and lateral position.

Trauma - Upper Limb

1. The primary goal of the Neer classification of proximal humeral fractures is to:

a) Determine the position of fragments
b) Determine the best surgical approach
c) Delineate the number of fragments
d) Determine the vascularity of the articular segment
e) Determine whether the fracture has dislocated


2. Implants protruding beyond the medial humeral neck can impinge on which of the following structures:

A) Axillary nerve
B) Axillary vein
C) Radial nerve
D) Axillary artery
E) Musculocutaneous nerve


3. A 34-year-old man involved in a motor vehicle accident sustains a pneumothorax, a closed femur fracture, and closed, displaced fractures of the ipsilateral humerus, radius, and ulna. Management of his femur fracture is open reduction internal fixation. Management of his humerus fracture should consist of:

a) Skeletal traction
b) Closed reduction and plaster immobilization
c) Open reduction and internal fixation of all fractures
d) External fixation of all fractures
e) Internal fixation of the humeral fracture and immobilization of the forearm fracture


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Answers

1.
Answer: D

Explanation:

Neer's four-part classification is designed to determine which fractures will result in avascular necrosis of the articular segment. In a four-part fracture, there is no residual blood supply to the articular segment.


2.
Answer: A

Explanation: With internal rotation, any implant protruding beyond the medial cortex of the humeral neck can impinge on the main trunk of the axillary nerve as it courses behind the humerus.


3.
Answer: C

Explanation: Indications for open reduction and internal fixation of humeral shaft fractures include open fractures, vascular injuries, floating elbow, polytrauma with multiple extremities, closed-head injury, and pathologic fractures.

MCQ: Diseases of the Cervical Spine

1. A young patient is diagnosed with torticollis. However, radiographs do not confirm a skeletal cause for the patient's head tilt and rotation. Nothing suggests a neoplastic origin for the disorder. What other tests/examinations should be performed:

A. Gastroenterologic examination
B. Stretching exercises
C. Ophthalmologic examination
D. Laboratory tests
E. A and C


2. Which of the following can be the presenting symptoms of patients with cervical myelopathy?

a. Gait disturbance
b. Clumsiness and loss of manual dexterity
c. Weakness in the lower extremities
d. Urinary incontinence
e. All the above


3. A unilateral decrease in the triceps reflex is most likely evidence of what clinical syndrome?

a. C5 radiculopathy
b. C6 radiculopathy
c. C7 radiculopathy
d. Cervical myelopathy
e. None of the above


4. Which of the following physical findings is consistent with cervical myelopathy?

a. A hyperactive knee-jerk
b. A positive jaw-jerk
c. Cog-wheel rigidity
d. Absent ankle reflexes
e. A positive axial manual traction test


5. Which of the following pathologic changes IS NOT seen in cervical spondylosis?

a. Increased water in the nucleus pulposus
b. Loss of annular elasticity
c. Disk space narrowing
d. Disk protrusion
e. Osteophyte formation


6. In an otherwise healthy 57-year-old patient, which of the following represents the most pressing relative indication for surgical treatment?

a. A history of chronic, severe axial neck pain
b. A large herniated disk on MRI of the neck
c. Cervical radiculopathy with neurologic findings
d. Cervical myelopathy
e. All the above require surgical treatment


7. What is the most common instability pattern seen in patients with rheumatoid arthritis of the cervical spine?

a. Atlantoaxial instability
b. Basilar invagination
c. Subaxial instability
d. Mixed
e. No one pattern is most common


8. A 6-year-old boy has neck pain and stiffness following an upper respiratory tract infection. He presented with his head tilted to the right and turned to the left 3 weeks ago, but a soft cervical collar has not been beneficial. There is no known history of trauma. A computerized tomography scan shows rotatory subluxation of C1 on C2. The next step in the treatment of this child is:

a. Observation
b. Open reduction and C1-C2 fusion through an anterior approach
c. In situ C1-C2 fusion posteriorly
d. Cervical traction
e. Hard cervical collar


9. If the C7 cervical spine nerve root is injured during a posterior decompression of the cervical spine, then sensation is lost in which of the following areas:

a. The lateral aspect of the arm from the shoulder to the elbow
b. The medial aspect of the arm from the shoulder to the elbow
c. The lateral border of the forearm including the thumb
d. The middle finger
e. The medial border of the forearm including the little finger


Answers:

1. E. Acquired torticollis may have several etiologies including neurologic, traumatic, or inflammatory. Sandifer's syndrome is a term used for gastroesophageal reflux accompanied by torsion spasms of the neck. Ocular torticollis occurs in children with alignment disorders (strabismus) causing them to tilt their heads to avoid diplopia. Stretching exercises to relieve torticollis work well only in congenital cases and before patients reach 1 year of age.



2. e.
Any or all of the above may be seen in a patient with cervical myelopathy. Abnormality of gait, particularly a broad-based and shuffling gait, is the hallmark abnormality of cervical myelopathy, but any of the above can be seen.


3. c
The triceps reflex is innovated by C7, and a diminished triceps reflex would be seen in a C7 radiculopathy.


4. a
Cervical myelopathy results in upper motor neuron findings for spasticity including hyperreflexia of the lower extremities, up-going toes, and, depending on the level of the spinal cord compression, hyperactivity in the upper extremities.


5. a
Spondylosis of the cervical (or lumbar) spine includes disk degeneration. The first and most striking finding in disk degeneration is a decrease in water content of the nucleus pulposus. All the other abnormalities are indeed seen in cervical and lumbar spondylosis.


6. d
In a relatively healthy, middle-aged patient, the presence of cervical myelopathy represents a fairly clear-cut indication for surgical treatment. The presence of chronic severe axial neck pain is usually treated nonoperatively. Patients with a herniated disk, even with evidence of radiculopathy, are usually treated nonoperatively, and that is certainly the first line of treatment in most cases.


7. a
All the above patterns of instability, including mixed patterns involving C1–C2, the occipitocervical junction, and the subaxial spine can be seen. Instability at C1–C2, however, is the most common pattern of instability seen.


8. d

This child has torticollis as sequelae of an upper respiratory infection (Grisel syndrome) and rotatory subluxation (fixation) of C1 on C2. Other causes of torticollis include congenital muscular torticollis, neurogenic causes, Sandifer syndrome, Klippel-Feil syndrome, juvenile rheumatoid arthritis, and trauma. The common thread is that all of the etiologies appear to weaken, through inflammation or force, the supporting soft tissue structures of the atlantoaxial articulation. The diagnosis is made by dynamic CT scan.

Fielding classified atlantoaxial rotatory subluxation into 4 types:

• Type I is a simple rotatory displacement without an anterior shift, and is the most common type in children.
• Type II is rotatory fixation with anterior displacement >3 to 5 mm, and is associated with a deficiency of the transverse ligament and unilateral displacement of one lateral mass of the atlas.
• Type III rotatory fixation there is anterior displacement >5 mm with bilateral displacement of the lateral mass with one side displaced more than the other. This is caused by a deficiency of both the transverse ligament and secondary ligament.
• Type IV is rotatory fixation with posterior displacement where the dens allows posterior shift of one or both of the lateral masses, and one shifting more than the other.

Types III and IV are rare but have potential for catastrophe and should be recognized to promptly initiate treatment.

Children with rotatory fixation of <1>

9. d

The C7 cervical spine nerve root supplies sensation to the skin over the volar aspect of the middle finger.

• C5 — Lateral aspect of the arm from the shoulder to the elbow
• C6 — Lateral border of the forearm including the thumb
• C7 — Middle finger
• C8 — Medial border of the forearm including the little finger
• T1 — Medial aspect of the arm from the shoulder to the elbow

Trauma - Lower Limb (1)

1. A patient presents to the emergency department with a segmental tibia fracture as a result of a gunshot injury with a 1-cm entrance wound. After appropriate irrigation and debridement, the wound measures 4 cm, there is no arterial injury, and the wound edges are easily approximated. Based on the Gustillo-Anderson classification, this wound is graded as:

(A) Type I
(B) Type II
(C) Type IIIA
(D) Type IIIB
(E) Type IIIC

2. Six weeks after open reduction and internal fixation of a talar neck fracture, an anteroposterior radiograph of the ankle reveals a lucency deep to the subchondral surface of the talar dome. This indicates:

(A) Malreduction of the fracture

(B) Osteonecrosis of the talus

(C) Collapse of the dome of the talus

(D) Associated tibial plafond impaction

(E) Revascularization of the talus

3. A Tillaux fracture of the distal tibia is the result of what mechanism of injury:

(A) Supination

(B) Pronation

(C) Dorsiflexion

(D) External rotation

(E) Internal rotation

4. In performing a lateral approach to the calcaneus for open reduction, internal fixation, the structure at risk is:

a) Lateral plantar artery
b) Lateral plantar nerve
c) Dorsalis pedism artery
d) Sural nerve
e) Superficial peroneal nerve


5. An 18-year-old woman arrives in your office 3 years after sustaining a comminuted right femur fracture treated with intramedullary (IM) nail fixation. She is complaining of moderate low back pain. On physical examination, you note that she has an 8-cm leg length discrepancy, and radiographs confirm that the right femur has healed 8 cm short. The most appropriate treatment at this point is:

A) Shoe lift on the right
B) Limb lengthening of the right femur
C) Limb shortening of the left femur
D) Observation
E) Left leg epiphysiodesis
6. Union rates of the femur after antegrade or retrograde reamed intramedullary nailing are:

A) Higher for antegrade nailing
B) Higher for retrograde nailing
C) Identical
D) Dependent on location in the bone
E) None of the above


7. A 39-year-old man sustained a grade II open diaphyseal tibia fracture that was treated with irrigation and debridement, external fixation, and delayed wound closure 12 weeks ago. At 9 weeks, the patient's weight bearing status was increased to partial weight bearing and the patient has since reported slight leg pain. Radiographs indicated a comminuted diaphyseal fracture of the tibia with no signs of callus formation. The radiographs also show no signs of loosening of the external fixator pins. Treatment at this point should include:

A) Removal of external fixator and placement of a patellar tendon bearing (PTB) cast, and progression to weight bearing as tolerated
B) Irrigation and debridement
C) Removal of external fixation and intramedullary nailing
D) Autogenous bone grafting
E) Placement of coralline hydroxyapatite into the fracture site8. Which of the following tibial fractures is most likely to have residual angulation (more than 5 degrees) after treatment with a statically locked intramedullary rod:

a) A distal third oblique fracture
b) A proximal third metaphyseal fracture
c) A comminuted midshaft fracture
d) A transverse midshaft fracture
e) An open transverse fracture with a large butterfly fragment



9. The most important factor in predicting cutout of an implant to repair intertrochanteric fractures of the hip is:

a) Size of the chosen screw
b) Posterior/inferior placement
c) Tip/apex distance
d) Pitch of the chosen screw
e) Angle of the plate
10. The optimal number of screws to repair displaced fractures of the femoral neck is:

A) Three
B) Five
C) Two
D) Four
E) Six


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Answers

1. C

Explanation:

Open fractures must be graded after the first debridement. Preoperative classification of open fractures often underestimates the degree of bone and soft tissue compromise. The Gustillo-Anderson classification divides open fractures into 5 groups:

• Type I fractures have an open wound less than 1 cm in length.
• Type II wounds measure greater than 1 cm but less than 10 cm without contamination, and the wounds can be closed without flap coverage.
• Type IIIA fractures have an open wound greater than 10 cm that can be closed with delayed primary techniques. Segmental fractures and gunshot injuries are also graded IIIA.
• Type IIIB fractures require rotational of free flap wound coverage.
• Type IIIC fractures are any open fractures with an associated vascular injury that requires repair.


2. E

Explanation:

The talus is composed of 7 articular surfaces covering 60% of the bony surface. Vascular access to the bone is limited to the nonarticular areas. An anastomotic sling of vessels provides the blood supply to the body of the talus that include: laterally, the artery of the tarsal sinus; medially, the artery of the tarsal canal, and additional arteries that enter dorsally through the neck and on the medial surface of the body.

The likelihood of talar body osteonecrosis increases with the severity of the injury. The diagnosis of osteonecrosis is routinely made radiographically by the absence of a Hawkin sign. This lucency deep to the subchondral surface of the dome of the talar dome on an anteroposterior radiograph of the ankle obtained 6 to 8 weeks after injury is an indication of revascularization.

3.

Answer: D

Explanation:

Tillaux originally described a special fracture occurring in older adolescents. The mechanism of injury is an external rotational force with stress placed on the anterior tibiofibular ligament, causing avulsion of the distal tibial physis anterolaterally. This occurs after the medial part of the physis has closed but before the lateral part closes. The resultant fracture through the physis runs across the epiphysis and distally into the joint, creating a Salter-Harris type III or IV fracture. Open reduction and internal fixation are indicated if the fracture is displaced. If left untreated, nonunions may result.

4.

Answer: D

Explanation: The sural nerve is the most likely structure to be at risk when performing a lateral approach to the calcaneus to perform an open reduction and internal fixation. Care must be taken to protect the small saphenous vein and sural nerve lying immediately posterior to the incision.



5.


Answer: B

Explanation:

The patient in question is at skeletal maturity. The approach to leg length discrepancies (LLD) depends on the length difference between the limbs. Discrepancies of more than 4 cm to 5 cm are treated with lengthening. Distraction is usually at the rate of 1 mm/day and is achieved by using Ilizarov principles, including metaphyseal corticotomy (preservation of the medullary canal and blood supply) and gradual lengthening. Lengthening over an IM nail may decrease the time in a distraction device.

• A shoe lift is reserved for differences less than 2 cm.
• The patient is at skeletal maturity so epiphysiodesis is not an option.
• Limb shortening of the unaffected limb is reserved for limb discrepancies of 2 cm to 5 cm.
• Observation is unlikely to change the patient's symptoms.

6.

Answer: C

Explanation:

Several studies have compared antegrade with retrograde nailing. When controlled for canal fit and degree of reaming, the biological effects of antegrade and retrograde nailing on union are identical. The entry portal is irrelevant to union of the fracture.


7.

Answer: D

Explanation: In this patient, the soft tissue has healed from his open wound. The patient is progressing toward a delayed nonunion due to lack of callus formation. The next step should include autogenous bone grafting. The progression of his weight bearing status will lead to loosening of his external fixator pins.


8.

Answer: B

Explanation: Fractures of the proximal third of the tibial shaft do not appear to respond as favorably to intramedullary nailing as do fractures in the distal two-thirds of the tibia. Valgus, apex anterior angulation, and residual displacement at the fracture site are common after nailing. Surgical errors of a medialized nail entry point and a posteriorly and laterally directed nail insertion angle contributed to malalignment. Based on their findings, the authors have limited the use of intramedullary nailing for proximal third tibial shaft fractures and consider alternate forms of fixation (plate or external fixation). An alternative technique is the use of blocking screws.


9.
Answer: C

Explanation: The most important factor in predicting cutout of an implant is the tip/apex distance. Screw design is a consideration but is limited by the anatomy of the proximal femur. Posterior/inferior placement was a factor used with old devices that did not purchase adequately in the femoral head.


10.
Answer: A

Explanation: Studies show that the optimal treatment for displaced fractures of the femoral neck is three parallel screws in a tripod configuration. Adding a fourth or fifth screw does not improve fixation, adds to technical difficulties, and theoretically, more vascular damage to femoral head can occur.