AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS
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Basic Science
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Question Book
, 2010 Orthopaedic Basic Science Examination Question Book· 7
Question 1
A comminuted femoral shaft fracture is treated with an intramedullary nail locked with a single distal
screw. What is the most likely mode of failure of the screw?
1. Screw pulls out of the cortical shaft
2. Screw head breaks off due to bending stresses
3. Shaft of the screw fractures in the region that is inside the nail
4. Screw threads are damaged by fretting against the edges of the holes in the nail
s. Screw bends excessively
Question 2
Glucosamine supplementation is used in the treatment of osteoarthritis due to its properties of
1. COX-2 inhibitory effects.
2. increasing synovial fluid viscosity.
3. direct spinal pain mediator.
4. substrate for proteoglycan formation.
5. inhibiting chondrocyte apoptosis.
Question 3
A surgeon is planning the application of a single plane external fixation construct as provisional fixation
for an unstable knee dislocation. There are two pin sizes available, one with twice the diameter of the
other. The bending stiffness of the larger pin is greater than that of the smaller by a factor of which of the
following?
1. 2
2. 4
3. 8
4. 16
5. 32
,8 American Academy of
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Question 4
Tumor of primary carcinoma may a focus metastases in bone attaching to the
endothelial layer of host bone via which the following?
l.
2.
3. Matrix (MMP)
4. Vascular endothelial growth factor (V EGF)
5. 12)
Question 6
are commonly used oncologic and arthroplasty What
to insufficiency?
1. 0% to
15% to 30%
3. to 60%
4. 70% to
5. 80% to 100%
7
can be by of the following radiographic changes in children?
1. physes
2. Widening of the ribs anteriorly
3. Rounded
Punched out metaphyseal with subperiosteal resorption
5. Sclerotic bands upper and lower of vertebra
, 2010 Orthopaedic Basic Science Examination Question Book· 9
Question 8
An obese patient underwent a posterior cruciate ligament-retaining total knee arthroplasty that has failed
and the patient is being considered for revision total knee arthroplasty. The patient also has medial
collateral ligament deficiency. In selecting a revision knee prosthesis, which of the following features is
considered to be essential?
1. The ability to retain the posterior cruciate ligament
2. A constraint mechanism that primarily resists varus-valgus loads
3. A constraint mechanism that primarily resists rotational loads
4. Femoral rollback
5. High conformity between the femoral and tibial articulating surfaces
Question 9
What is the most important muscle adaptation resulting from endurance training?
1. Increased recruitment of motor units
2. Formation of additional myofibers (hyperplasia)
3. Hypertrophy of individual myofibrils
4. Increase in capillary density
5. Increased activity of glycolytic enzyme
Question 10
A patient has a C6-7 herniated nucleus pulposus. What is the most likely distribution of symptoms?
1. Pain in the posterior neck and scapula, numbness over the clavicle, and weakness of the head
and neck extensors
2. Pain in the shoulder, numbness over the lateral shoulder, weakness of the deltoid
3. Pain at the elbow, numbness over the thumb and index finger, weakness of the biceps and wrist
extensors
4. Pain at the forearm and hand, numbness of the middle finger, weakness of the triceps and
finger extensors
5. Pain at the wrist, numbness in the little and ring fingers, weak finger flexors