2012 Flashcards
Best indication for Ex fix in a BBFA:
a. Grade IIIB
b. Grade IIIC
c. Comminuted
d. Segmental
A
By definition in a IIIB fracture you don’t have adequate soft tissue coverage, so you can’t plate it. In a IIIC fracture, however, you can do a vascular shunt to reperfuse the hand, perform your plating, then do a formal vascular repair after you have bony stability. This would be a reasonable alternative to ex-fixing the fracture and then doing a vascular repair followed by a later exchange to plating.
50 yr Secretary had carpal tunnel release 6 months ago and still has hand/wrist pain. OE has tinels on scar on radial side of wrist at the wrist crease. Negative Phalen’s. 5 mm 2 pt discrimination in fingers. Thumb power normal. What is the problem?
a. Partial transverse carpal ligament release
b. Damage to the Recurrent motor branch
c. Incomplete carpal tunnel release
d. Damage to the palmar cutaneous branch
D
Normal motor function = Damage to recurrent motor branch out (option B).
Normal 2 pt and normal motor = Median nerve likely out as well
Options A & C would imply the same entity
A question on Tip-to-Apex distance when using a DHS. Which of the following does not lead to a poor result?
a. Using a 150 instead of a 135 degree plate
b. Female gender
c. Tip apex <25mm
d. Using this device in an unstable fracture pattern
C
A, B, and C are all associated with increased failure.
30 yr dude with posterior mall and lateral mall fracture. No medial mall fracture. Talus 40% subluxated posterior. Lateral Mall is oblique at the joint line. What provides the most stable fixation?
a. One lag screw and lateral plate
b. Two lag screws
c. One lag screw and posterior plate
d. Tension band Wire
C
Posterior plating has superior strength
Guy who does a lot of work with repetitive lifting and elbow flexion. Has weakness to digital extension and his wrist radially deviates with extension. Failed all non-op. What to decompress?
a. Intermuscular septum 5cm proximal to lateral epicondyle
b. Struther’s ligament
c. Lacertus fibrosis
d. Proximal supinator edge
D
NO = Intermuscular septum would get RADIAL NERVE PROPER (rare). Radial nerve proper is intact b/c the ECRL is working (he radially deviates with wrist extension)
NO = Struther’s ligament compresses MEDIAN nerve, it is a ligament that passes b/t a supracondylar process on the humerus and the medial epicondyle (this is different from the arcade of struthers, which compresses the ulnar nerve and is the opening of the IM septum through which the ulnar nerve passes)
NO = lacertus fibrosis (bicipital aponeurosis) compresses MEDIAN nerve
YES = Proximal supinator edge = ARCADE OF FROHSE, most common site of PIN compression.
PIN compression syndrome:
Causes motor deficits only, there is no sensory component.
Radial drift with wrist extension is caused the fact that the ECRL is innervated by the radial nerve proper, where as the ECU is innervated by the PIN. Therefore, the patient can still extend the wrist, but b/c the ECU does not work and the ECRL does, there will be radial deviation.
Guy falls off ladder and has numbness over deltoid, weak abduction, scapular winging. Now 1 month out from injury. What did he injure?
a. C6 root
b. Axillary nerve
c. Upper trunk
d. Posterior cord
A
Medial scapular winging is due to serratus anterior deficiency, which is supplied by the long thoracic nerve injury. The long thoracic nerve comes off the c5 and c6 nerve roots, prior to the “trunks” of the brachial plexus. It is the earliest termial branch that comes off the brachial plexus. Therefore, the only option above that would cause winging is an injury to the c6 root.
The axillary nerve supplies the patch area, which has fibers from both the c5 and c6 root. Therefore, damage to either c5 or c6 can impair axillay nerve function and lead to loss of sensation over the lateral deltoid as well as loss of lateral deltoid motor function.
If C5 was an option I would choose that
What is the mechanism of injury of BADO 1 monteggia fracture? RE
a. anterior blow to forearm
b. hyper pronation
c. hyper supination
d. valgus load to elbow.
B
Three separate mechanisms of type I lesions have been described:
1. direct trauma to posterior forearm (traditional belief, but not as common)
2. hyperpronation during FOOSH
3. hyperextension, anterior radial head dislocation, then ulna fracture
Regarding SCIWORA (spinal cord injury without radiographic abnormality), what is true?
a. Often a delayed presentation
b. most common in the T spine
c. infantile cord can stretch 2 inches before rupture
d. most commonly seen in 8-15yo
A
JAAOS Pediatric Cervical Spine Trauma J Am Acad Orthop Surg 2011;19: 600-611
SCIWORA occurs in 18% to 38% of pediatric cervical spine injuries, and the incidence tends to be higher in young children. The mechanism of injury likely relates to the flexibility of the pediatric spine, which is greater than that of the spinal cord. It is believed that the spinal column can stretch up to 2 inches, whereas the spinal cord may rupture when stretched <1 cm.
You think there is a LT tear. They describe a palmar flexed triangular lunate on the PA films. What do you expect on the plain films to support a Dx of a LT tear?
a. Shortened scaphoid
b. SL angle of 45
c. Gap in the LT space
d. No cortical ring sign
A
JAAOS. 2001. Lunotriquetral Tears
Scaphoid flexes with Lunate with there is a LT tear. If scaphoid is flexed then scaphoid is short and there will be a cortical ring sign. Unlike with a SL tear, LT tear rarely causes a gap. SL angle decreases (VISI deformity) when there is an LT tear, so it will be less than 30 degrees (normal is around 30-60).
Highest Rate of progression for congenital Scoliosis
a. Hemivertebrae (did not specify ty[e)
b. Unilateral unsegmented Bar
c. Double hemivertebrae
d. Wedge
B
Hedequist D and Emans J. Congenital scoliosis. JAAOS 2004;12:266-275.
Rates of progression for specific anomalies.
Type of Anomaly Progression(per year)
- Block vertebra < 2 deg
- Wedge vertebra < 2 deg
- Hemivertebra 2–5deg
- Unilateral bar 5–6deg
- Unilateral bar with contralateral hemivertebra 5 – 10 deg
When performing a valgus intertrochanteric osteotomy and bone grafting for a nonunion of a femoral neck fracture in a 40 year old, all of the following are true, except?
a. Need to medialize the shaft as much as possible
b. It is best to leave at least 2 cm between entry point of blade plate and osteotomy
c. Aiming for angulation of fracture line to horizontal of 20-30 degrees
d. There is a high union rate but a limp persists
A
The osteotomy is then performed. Its proximal cut must be parallel to the chisel path, taking care to leave at least 1.5 to 2 centimeters of bone between the blade and the osteotomy, thereby minimizing the chance of failure of this bony bridge, which is crucial for proximal fixation
The author currently attempts to minimize the amount of femoral shaft medialization when performing such osteotomies. One technique is to choose a slightly long blade. When seated to the appropriate depth, the plate remains lateral, which assists in keeping the shaft lateral. Shaft medialization decreases offset, therefore decreasing abductor efficiency and increasing the joint reactive force. Additionally, excessive shaft medialization may cause valgus alignment at the knee.
To be perpendicular to the joint reaction force resultant, the nonunion plane should make an angle of 20°–30° perpendicular to the femoral axis
12 yr boy with Duchennes; ~32 degree curve, pelvic obliquity 15. FVC of ~55%; what is the best management?
a. Anterior and posterior approach and posterior only instrumentation
b. Posterior only approach and fusion
c. Sitting modifications in wheel chair
d. Brace
B
A: Standard is posterior only
C: Scoliosis progresses rapidly once patient no longer ambulatory. Early surgery is recommended. Ideally when curve is 20-30 degrees
D: Brace not effective in DMD
With regards to triplane fractures in children?
A. Results from lateral rotation
B. Occurs because posteromedial physis closes first
C. High risk of growth arrest
D. Can not happen with growth plates are fully open
A
A: ER is the typical mechanism
B: Order of distal tibial physis closure - central> anteromedial> posterolateral> anterolateral
C: Transitional fracture, so not much growth remaining if any
D: Does sometimes happen with open physis (not common)
Conditions associated with secondary development of Chondrosarcomas. All except:
a. Olliers
b. Mafuccis
c. MHE
d. McCune Albright syndrome
D
Ollier’s Disease:
-This is multiple enchondromatosis.
-Patients have multiple enchondromas throughout the diaphysis and metaphysis
-It is associated with skeletal dysplasia secondary to failure of endochondral ossification
-25% risk of malignant degeneration of an echondroma
Maffuci’s Syndrome:
-This is condition with multiple enchondromas AND soft tissue angioma’s
-Associated with a 100% risk of malignant transformation of enchondromas, as well as visceral malignancies of the GI tract and astrocytomas
-Mnemonic: Maffuci’s in MEAN (Multiple Enchondromas, ANgioma’s and its mean b/c they all turn malignant)
Multiple Hereditary Exostoses:
-Condition in which you get multiple osteochondromas
-Associated with a mutation in the EXT1 and EXT2 gene, which leads to loss of regulation of the indian hedge hog protein
-5-10% risk of developing a secondary chondrosarcoma from one of the osteochondromas
-Suspect malignant degeneration when there is an acute onset of pain and an associated cartilage cap of greater than 2cm
McCune Albright Syndrome:
-This is a dz with coast of maine café au lait spots, endocrine abnormalities (precocious puberty and renal phosphate wasting) and unilateral poloostotic fibrous dysplasia
-There is an associated 1% risk of transformatino of the fibrous dysplasia into osteosarcoma, fibrosarcoma and UPS (aka MFH)
All are associated with swan-neck deformity in RA patient EXCEPT?
a. Patient unable to passively extend MCP
b. Positive Bunnell
c. Chronic Mallet finger
d. MCP collaterals demonstrating increased laxity when flexed to 90 degrees
D
JAAOS 2006.
Causes of swan neck deformity in RA (i.e., causes of pip hyperextension)
- extensor subluxation/saggital band rupture
- volar mcp subluxation
- intrinsic muscle tightness
- volar plate attenuation
- fds laxity
- transverse retinacular ligament attenuation
- triangular ligament contraction
- rupture of terminal tendon (mallet)
All of the following make up the quadrangular space except?
a. Humerus
b. Teres major
c. Infraspinatus
d. Long head of tripeps
C
What is a characteristic of an NOF
a. Epiphyseal
b. Eccentric
c. Multiloculated
d. Less than 1cm
B
All of the following regarding transient osteoporosis is true except:
a. Happens mostly in middle aged men
b. Half of cases are in the upper extremity
c. It is associated with no significant loss of range of motion
d. It is self limiting
B
18 year-old female presents to you complaining of her shoulder going “in and out” when swimming or playing volleyball. Never had a traumatic dislocation. Which of the following is the best option for treatment of her instability?
a. Bankart repair
b. Magnuson-Stack procedure
c. Inferior capsular shift
d. Putti-Platt procedure
C
Multidirectional instability
With depletion of ATP in hypoxia secondary to hypovolemia, which of the following represents the correct description for changes in the intracellular milieu?
a. Decreased sodium, increased potassium, decreased water
b. Decreased sodium, decreased potassium, decreased water
c. Increased sodium, decreased potassium, no change in water
d. Increased sodium, decreased potassium, increased water
D
What nerve injury has a disrupted axon and intact endoneurium?
a. Neurpraxia
b. Axonotmesis
c. Neurotmesis
d. Electrotmesis
B
Conditions associated with NF-1; all except
a. Hypertension
b. Astrocytoma
c. Short stature
d. Acoustic Neuroma
D
Acoustic neuromas are associated with NF2
Astrocytomas are a type of glioma (non malignant CNS tumor)
