Journal of Bone and Joint Surgery (British Volume)

CME questions October 2008

Refresh your memory with the October 2008 CME questions and then click on the link at the bottom of the page to find out the answers.

1. Which of the following statements concerning the anatomy of the Anterior Cruciate Ligament is incorrect
1. The anteromedial bundle arises more distally on the femur than the posterolateral bundle
2. The posterolateral bundle inserts posterolateral to the anteromedial bundle on the tibia
3. There is no histological evidence that two separate bundles exist
4. With the knee extended the two bundles of the ACL run approximately parallel to each other
5. With the knee flexed the two bundles of the ACL twist around each other
2. What is the perceived advantage of double bundle techniques of anterior cruciate ligament reconstruction?
1. Control of both anterior and posterior laxity
2. Improved control of rotatory laxity
3. Improved fatigue resistance
4. Increased load to failure
5. Reduced risk of interface fixation failure
3. In cadaveric studies of ACL reconstruction, which of the following statements is correct?
1. Arthrometer measurements suggest that double bundle reconstruction is superior to single bundle when AP laxity is measured at 60o flexion
2. Double bundle reconstruction fails to restore near-normal anterior laxity at 20o flexion
3. Double bundle reconstruction fails to restore near-normal anterior laxity at 90o flexion
4. The in situ force in the anteromedial bundle at 90o flexion is higher than in the posterolateral bundle
5. The in situ force in the posterolateral bundle at 0o flexion is lower than in the anteromedial bundle
4. Which of the following assessments will not distinguish ACL deficient copers from non-copers?
1. <10%
2. 20%
3. 33%
4. 50%
5. 67%
5. According to the Anderson Orthopaedic Research Institute classification system, which of the following is a Type T2B?
1. Damaged tibial metaphyseal bone with cancellous defects of both tibial condyles that require augmentation or grafting
2. Intact metaphyseal bone with small central defect of lateral tibial plateau of about 5mm
3. Loss of one femoral condyle that can be augmented to restore the joint line
4. Loss of 40% of the medial tibial rim with the cortical attachment of the medial collateral ligament
5. Loss of 70% of the margin of the medial tibial condyle with associated metaphyseal cortex to approximately 7cm below the joint line and an associated large central cancellous defect
6. Which of the following dental procedures is not associated with a transient bacteraemia?
1. Periodontal probing
2. Periodontal surgery
3. Teeth brushing
4. Ultrasonic scaling
5. Upper alginate impression
7. Which of the following statements concerning bacteraemia in relation to dental procedures is incorrect?
1. The average duration of a transient daily bacteraemia is approximately 11 minutes
2. The cumulative risk of ‘spontaneous’ bacteraemia from chewing etc can be considerably higher than the risk from dental interventions
3. The incidence of positive blood cultures is higher after dental procedures lasting more than 6 minutes than those lasting less than 3 minutes
4. Transient bacteraemia occurs up to 12 times every day
5. Within 30 seconds of tooth extraction 90% of blood cultures are positive
8. According to the Osteoarthritis Research Society International grading system, which description below best fits grade 4?
1. Surface intact with matrix oedema, cell death with concomitant proliferation in clusters
2. Surface and matrix discontinuity in superficial zone, cell death, proliferation and hypertrophy
3. Vertical fissures into mid-zone, branched fissures, cell death, proliferation and hypertrophy
4. Erosion, matrix loss with delamination, mid-layer cyst formation and excavation of superficial/mid-zones
5. Denudation with sclerotic bone or reparative tissue (fibrocartilage) at surface
9. Which of the following species is both a common cause of prosthetic joint infection and a commonly cultured organism from blood cultures taken after dental work?
1. Actinomyces
2. Gemella sp
3. Neisseria sp
4. Staphylococcus sp
5. Streptococcus sp
10. If all patients undergoing dental treatment with an artificial joint in situ were given antibiotic prophylaxis, which of the following outcomes is predicted?
1. A greater reduction in bacteraemia would be seen after dental extraction than if the patient had used chlorhexidine mouthwash instead
2. Bacteraemia will not occur
3. More patients will die of anaphylactic shock than would die of infection
4. Significant cost savings would be realized
5. There will be a significant reduction in infection of the artificial joints
11. Which of the following will result from excessive internal rotation of the femoral component at knee replacement?
1. Increased extension gap with no change to flexion gap
2. Lateral condylar lift off at 90o flexion
3. Medial condylar lift off and varus coronal laxity in flexion
4. Tight flexion, lax extension
5. Valgus laxity in extension
12. What is the published wound infection risk for patients who are HIV positive, not receiving HAART treatment, undergoing internal fixation of open fractures?
1. 2%
2. 5%
3. 10%
4. 25%
5. 50%
13. Below what pre-operative concentration of haemaglobin does the risk of mortality increase significantly?
1. 4 g/dl
2. 6 g/dl
3. 8 g/dl
4. 10 g/dl
5. 12 g/dl
14. Which of the following blood products appears to be at greatest risk of bacterial contamination?
1. Factor VIII concentrate
2. Leukocyte depleted erythrocyte concentrates
3. Plasma
4. Platelet concentrate
5. Whole blood
15. What is the best predictor of the need for blood transfusion after joint replacement?
1. Body weight
2. Past history of blood transfusion after joint replacement
3. Patient age
4. Preoperative haemoglobin concentration
5. Preoperative haematocrit
16. Which of the following individuals, each weighing 80 kg, will have the biggest erythrocyte stock?
1. Lean male, normal haematocrit
2. Lean female, normal haematocrit
3. Obese male, normal haematocrit
4. Obese female, normal haematocrit
5. Obese female, haematocrit 5% higher than median normal
17. Which of the following procedures is associated with the biggest occult blood loss?
1. Hemiarthroplasty for hip fracture
2. Intramedullary nail fixation of hip fracture
3. Screw fixation of hip fracture
4. Total hip replacement
5. Total knee replacement
18. Which of the following techniques has not been shown to reduce blood loss during or after joint replacement?
1. Elevation of the lower limb after knee replacement
2. Intravenous Tranexamic acid
3. Local application of platelet gel before wound closure in knee arthroplasty
4. Spinal or epidural rather than general anaesthesia
5. Systemic Desmopressin
19. Which of the following statements concerning autologous blood predonation before total joint replacement is incorrect?
1. Incidents and complications are more than 10 times more frequent in autologous blood donors than in blood bank donors
2. Most (more than three quarters) of predonated blood is used for transfusion
3. Predonated autologous blood that is not used should not be given to other matched patients
4. The absolute risk for allogenic blood transfusion is reduced by more than 40%
5. The risk of blood transfusion is increased
20. Which investigative technique has identified the fate of the erythrocytes that constitute the ‘occult’ component of peri-operative blood loss?
1. Gallium labelled white cell scanning
2. Isotope bone scanning (blood pool phase)
3. MRI
4. Scintigraphy with labelled erythrocytes
5. Ultrasound
21. In a recently updated meta analysis of wound drainage after orthopaedic surgical procedures, which of the following was identified as occurring more commonly when drains were used?
1. Blood transfusion
2. Haematoma formation
3. Re-operation
4. Wound dehiscence
5. Wound infection
22. Which of the following, if measured in blood that is reinfused from drains after simple filtration, will be quantitatively lower in the reinfused blood?
1. Activated compliment factor C3
2. Haematocrit
3. Histamine
4. Inflammatory mediators
5. Myeloperoxidase
23. Which of the following microscopic features of torn rotator cuff tendon tissue appears most likely to be associated with a higher risk of re-rupture after repair?
1. Chondroid metaplasia
2. Increased cellular synthesis of type-1 procollagen
3. Increased expression of leucocyte markers
4. Increased fibroblast cellularity
5. Intimal hyperplasia
24. Which of the following statements concerning the prevalence of rotator cuff tears is correct?
1. Asymptomatic tears are found in 25% of patients aged between 60 and 80 years
2. In patients who return for a second scan, 50% of asymptomatic tears become symptomatic after 5 years
3. In patients with symptomatic cuff tears the cuff on the opposite side is usually degenerate but not torn
4. The overall prevalence of asymptomatic full thickness tears on MRI and ultrasound scanning is less than 10%
5. The prevalence of full thickness tears in elderly cadavers is more than 50%
25. Which of the following statements concerning rotator cuff repair is most correct?
1. After repair of massive rotator cuff tears up to 20% re-rupture
2. Double row repairs have a superior functional outcome to single row techniques in most clinical studies
3. Most patients who suffer a re-rupture maintain their improvement in pain and function
4. Strength at follow up is independent of whether or not the repair is intact
5. The rerupture rate after repair is higher in young, active patients

Find the answers to the October 2008 CME here.
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