Journal of Bone and Joint Surgery (British Volume)

CME questions October 2006

These papers have been set on the review articles and aspects of current management papers from the 2006 July, August and September issues of the British Volume of the JBJS.

1. Which of the following is an example of a multipotent stem cell?
1. embryonic stem cell
2. fertilized oocyte
3. zygote
4. mesenchymal stem cell
5. morula
2. Concerning the risks of stem cell therapy, which specific tumour risk is much less when adult stem cell are used rather than embryonic stem cells
1. Leukaemia
2. Multiple myeloma
3. Plasmacytoma
4. Teratoma
5. Choriocarcinoma
3. Which of the following is a contraindication to bone donation?
1. treated carcinoma in situ of the cervix
2. squamous cell carcinoma of the skin
3. basal cell carcinoma of the skin
4. evidence of human papillomavirus infection
5. fibroadenoma of the breast
4. Which of the following is not a mandatory serological test for bone donors ?
1. syphilis
2. HIV 1-2 antibodies
3. hepatitis B core antibodies
4. hepatitis C virus antibodies
5. hepatitis E virus antibodies
5. Which of the following methods of sterilisation has the least adverse effect on the mechanical properties of donated bone ?
1. 25kGy irradiation of frozen bone
2. 25kGy irradiation of bone at room temperature
3. 25kGy irradiation of freeze dried bone
4. 60kGy irradiation of frozen bone
5. 60kGy irradiation of bone at room temperature
6. Which of the following will not improve the biomechanical properties of impacted graft prior to the insertion of a prosthesis ?
1. removal of all articular cartilage from the donor femoral head before milling
2. use of ungraded graft particles rather than uniformly sized particles
3. increasing the number of impactions from 30 to 50
4. addition of small bioglass spheres to the graft before impaction
5. use of tricalcium phosphate / hydroxytappatite graft extender
7. According to Positron Emission Tomography studies, for how long does graft incorporation proceed after impaction grafting of the femur ?
1. six months
2. one year
3. two years
4. five years
5. indefinitely
8. How do methods of preparation of tendon grafts affect the immunogenicity of the graft
1. by removing all traces of blood and blood products
2. by altering the chemical structure of the collagen
3. by killing any bacteria introduced as contaminants
4. by killing fibroblasts
5. by denaturing any antibodies in the graft
9. After what time period after implantation is graft remodelling complete after implantation of autogenous tendon graft.
1. 2 months
2. 6 months
3. 12 months
4. 2 years
5. 5 years
10. For which of the following conditions potentially transmissible through allografting of tendons is there no donor screening test available.
1. Creutzfeld-Jakob disease
2. HIV
3. Hepatitis C
4. Hepatitis B
5. Clostridial infection
11. What is the approximate reduction in odds of obtaining an excellent or good result that occurs with the passage of each day after injury when internally fixing acetabular fractures.
1. 2%
2. 5%
3. 10%
4. 20%
5. 50%
12. What sort of molecule is Botulinum neurotoxin.
1. An amino acid
2. A polypeptide
3. A protein
4. A lipopolysaccharide
5. An aromatic amine
13. How does botulinum toxin exert its effect
1. By blocking nicotinic receptors
2. By blocking cholinergic receptors
3. By causing massive release of noradrenaline
4. By blocking acetyl choline release
5. By potentiating the action of neuropeptides
14. What is the approximate duration of chemodenervation with muscle relaxation that occurs after administration of botulinum toxin - A
1. 15 minutes
2. 15 hours
3. 15 days
4. 15 weeks
5. 15 months
15. In which of the following muscles would a single injection of botulinum toxin A, accurately injected for maximum effect, be most likely to infiltrate the endplate zone
1. Deltoid
2. Biceps brachii
3. Sartorius
4. Gracilis
5. Gastrocnemius
16. Consider the following list of observed measurements: 1,1,3,3,4,5,5,6,6,6,7,8,8,10,15,20 What is the interquartile range of these measurements?
1. 2.11
2. 6
3. 6.125
4. 3 - 15
5. 4 - 8
17. A series of observations are considered, some with positive values and some with negative. In order to study the variance of these observations the numerical value of each is subtracted from the arithmetic mean and the result is squared to eliminate negative values. The sum of the resultant for all values is then divided by the number of observations (minus one) to give a measure of variance. Since the values were squared, what statistic results if the square root of this measure of variance is calculated?
1. Root mean square
2. Geometric mean
3. Standard deviation
4. Reference range
5. Confidence interval for the mean
18. What is the probability of finding a statistically significant difference between two parameters under statistical study when no difference actually exists
1. 'p'
2. the power of the study
3. 1/ the power of the study
4. 5%
5. 'z'
19. Which of the following statements concerning the Pearson correlation coefficient is correct
1. the greater the sample size, the smaller the p value associated with any numerical value of correlation coefficient.
2. the smaller the sample size, the smaller the p value associated with any numerical value of correlation coefficient
3. the significance of any particular correlation coefficient is not related to the sample size
4. the correlation coefficient is a direct measure of statistical significance
5. values of greater than 1 are statistically significant
20. Which of the following statements is true for both the Perason correlation coefficient and the Spearman correlation coefficient
1. both are measures of the linear relationship between one variable and another
2. both can have values from -1 to +1
3. both are used for parametric data
4. both can be used if one, but not both, variables are ordinal
5. if squared, the correlation coefficient is a measure of 'goodness of fit'
21. At least how many individuals should be included in a study of six covariates to be studied by multiple linear regression.
1. 6
2. 10
3. 36
4. 60
5. 360
22. The Cox proportional hazards regression analysis assesses the independent effect of multiple variables on the hazards ratio. What analysis is used to assess the effect of a single variable.
1. Mean survival time
2. Relative Hazard
3. Kaplan Meier survival analysis
4. Logrank test
5. Poisson regression analysis
23. What represents the proportion of patients with a positive test result that actually have the disease or condition that the test was intended to detect.
1. the sensitivity of the test
2. the specificity of the test
3. the reliability of the test
4. the positive predictive value of the test
5. the negative predictive value of the test
24. What statistic identifies the proportion of times that two observers agree on the classification of categorical data, modified to account for the number of times the agreement would occur by chance alone.
1. Pearson correlation coefficvient
2. Spearman rank correlation coefficient
3. Reproducibility coefficient
4. Kappa statistic
5. Weighted Kappa statistic
25. What action should be taken if an individual in one arm of a randomised controlled trial violates the protocol by switching treatment to that of the other arm of the trial.
1. Include the individual in the analysis as if they were still in their originally allocated group
2. Include the individual in the analysis as if they had always been in the group to which they switched
3. Omit data from that individual from analysis of the original group
4. Omit data from that individual from analysis of the original group and one randomly selected patient from the group to which they switched
5. Analyse the results from that individual as if they were in the group that undergoes the intervention under study if they were subjected to that intervention.

Here are the answers to the October 2006 CME test paper.