Question

21. Match each of the following descrintions of positioning for projections of the knee and/or paten name or term. (Use each answer only once.) sitioning for projections of the knee and/or patella to its correct 1. Can be performed using a wheelchair or lowered A. Inferosuperior for patellofemoral joint radiographic table B. Merchant method 2. Patient prone; requires 90° knee flexion C. Hughston method 3. Patient prone with 40 to 50° knee flexion and with equal 40° to 50° caudad CR angle D. Camp-Coventry method 4. IR is placed on a foot stool to minimize the OID E. Settegast method 5. Patient prone with 55° knee flexion and 15 to F Holmblad method (variation) 20° CR angle from long axis of lower leg. G. Hobbs modification 6. Patient supine with cassette resting on midthighs 7. Patient supine with 40° knee flexion and with 30 caudad CR angle from horizontal 28. Which of the following special projections of the knee must be performed erect? A. Rosenberg method C. Settegast method B. Camp-Coventry method D. Hughston method 20. True/False: The recommended SID is 48 inches (123 cm) to 72 inches (183 cm) for the tangential (bilateral Merchant) projection. 30. How much knee flexion is required for the horizontal beam lateral patella projection? A. 5° or 10° C. 25° or 30° B. 15° to 20 D. None REVIEW EXERCISE E: Problem Solving for Technical and Positioning Errors este. A radiograph of an AP projection of the foot reveals that the metatarsophalangeal joints are not open and 1. Situation: the metatarsals at metatarsals are somewhat foreshortened. What positioning error was involved, and what modification should be made to improve this image on the repeat exposure? Situation: A radiograph of an AP oblique-medial rotation projection of the foot reveals that the proximal third to Ak metatarsals are superimposed. What type of positioning error led to this radiographic outcome? u tion: A radiograph of a plantodorsal axial projection of the calcaneus reveals considerable foreshortening of the calcaneus. What type of positioning modification is needed on the repeat exposure?

Answer 1

27.

1. Holmbald Method (variation)

2. Settegast Method

3. Camp-Coventry Method

4. Hobbs modification

5. Hughston Method

6. Inferosuprerior for patellofemoral joint

7. Merchant Method

28. A Rosenberg Method

29. TRUE

30. NONE

31. Central ray is not angled correctly. It should be perpendicular to metatarsals. Adjust the central ray angle to perpendicular position to avoid position error.

32. Over-rotation of foot is the positioning error that occurred here.

33. The position modification needed here is increase the cephalad angle of the central ray to correctly elonagate the calcaneus.