This document provides information on various knee radiographic views including: - AP, lateral, tunnel, oblique views of the knee joint - Weight bearing AP view - Patella PA, lateral, oblique axial views - Various tangential views of the patella including sunrise, Hughston, Settegast, seated, Merchant, and Laurine views It describes the patient positioning, part positioning, direction of the central ray, and evaluation criteria for each view to properly assess the knee anatomy and identify any abnormalities.

1. Knee Joint Views
Dr P Vinayak Sharad Abhishek,
Radiodiagnosis Resident,
BMC
1

2. NOTE
• FOR ALL THE VIEWS WE ARE GOING TO
CONSIDER THE FOLLOWING TOPICS:
POSITION OF PATIENT
POSITION OF PART AND CASSETTE
DIRECTION & CENTRING OF THE CENTRAL
X-ray BEAM
EVALUATION CRITERIA
2

3. NOTE
• ALL THE VIEWS ARE TAKEN WITH
SOME DEGREE OF TUBE ANGULATION
EXCEPT ERECT LATERAL VIEW
3

4. A P VIEW
• FILM:
• 8 * 10 inch
• POSITION OF PATIENT :
• Place the patient in supine position and adjust
the body so that there is no rotation of the
pelvis.
4

5. •POSITION OF PART
• With the cassette under the patient’s knee
• Flex the joint slightly
• Locate the apex of patella
• As the patient extends the knee center the
cassette about ½ inch below the patellar apex
• Adjust the leg in a true AP position
• The patella will lie slightly off center to the
medial side
5

6. •CENTRAL RAY
• When radio graphing the joint space:
• Angle the tube so that the central ray is directed to a
point ½ inch inferior to the patellar apex at an angle
of 5 to 7 degrees cephalad
• When radio graphing the distal end of femur or the
proximal ends of the tibia and fibula:
• The central ray may be directed perpendicularly to
the joint
6

7. A P VIEW
7

8. A P VIEW
8

9. •Evaluation Criteria
• Femorotibial joint space should be open.
• Patella should be completely superimposed on the
femur.
• No rotation of the femur and tibia should be seen.
• Soft tissue around the knee joint should be seen.
• If the knee is normal, the interspaces should be equal
in width on both sides.
• Slight superimposition of the fibular head and the
tibia is normal.
9

10. AP VIEW
10

11. LATERAL VIEW
• FILM:
• 8 * 10 inch
• Position of patient:
• Ask patient to turn onto affected side
• Ask the patient to bring the knee forward in
flexion and extend the other extremity behind it.
• A flexion of 20 to 30 degrees is preferred as this
position relaxes the muscle and shows the
maximum volume of the joint cavity.
11

12. •Position of part
• Flex the knee to the desired angle and center
the film to the knee joint.
• The knee joint lies just below the level of
patellar apex and approx. ½ inch distal to the
medial femoral condyle.
• The joint can be easily located by palpating
the depression between the femoral and tibial
condyles on the medial side of the knee.
12

13. •Central ray
• Direct the central ray to knee joint located ½
in (1cm) distal to the medial epicondyle at an
angle of 5 degrees cephalad. This slight
angulation of the central ray will prevent the
joint space from being obscured by the
magnified shadow of the medial femoral
condyle.
13

14. LATERAL VIEW
14

15. LATERAL VIEW
15

16. •Evaluation criteria
• Femoral condyles should be superimposed.
• Joint space between femoral condyles and tibia should
be open.
• Patella should be in lateral profile.
• Femoropatellar space should be open.
• Fibular head & tibia should only be slightly
superimposed.
• Knee should be seen flexed approximately 20 to 30
degrees.
• All soft tissue around the knee should be included.
• Femoral condyles should be demonstrated with proper
density.
16

17. 17

18. Weight-Bearing Knee
• AP VIEW
• Bilateral weight-bearing AP projection should be
routinely included in the radiographic examination
of arthritic knees.
• It often reveals narrowing of a joint space that
appears normal on the non-weight-bearing study.
• It also permits more accurate estimation of degree
of lower extremity varus or valgus deformity, and
this aids in preoperative and postoperative
evaluation of knees undergoing osteotomy.
18

19. •Position of patient
• The patient is placed in the upright position
before and with his or her back toward a vertical
grid device.
• Center the film at the level of the apices of the
patellae.
• Film :
• 10*12 inches.
19

20. •Position of part
• Ask the patient to place the toes straight
ahead, with the feet separated enough for
good balance.
• Centre the knees to the film.
• Ask the patient to stand straight with his or
her knees fully extended and weight equally
distributed on the feet.
20

21. •Central ray
• Direct the central ray horizontally and center it
midway between the knees at the level of the
apices of the patellae.
21

22. WB VIEW
22

23. •Evaluation criteria
• Knees should not be rotated.
• Both knees should be demonstrated.
• Knee joint space should be centered to the
exposure area.
• A large enough film should be used to
demonstrate the longitudinal axis of the
femoral and tibial shafts.
23

24. • note:
• For a weight-bearing study of a single knee,
have the patient put full weight on the affected
side.
• The patient may balance with slight pressure
on the toes of the unaffected side.
24

25. WB VIEW
25

26. AP OBLIQUE POSITION
• FILM:
• 8 x 10 inch
• POSITION OF PATIENT:
• Place the patient on the table in the supine
position and support the ankles.
26

27. •Position of part
• Lateral (external ) oblique position :
• Elevate the hip of the unaffected side enough to
rotate the affected limb 45 degrees laterally.
• Support the elevated hip and knee of the
unaffected side.
• Place the cassette parallel with the long axis of
the knee, center the cassette approximately ½
inch below the apex of the patella.
27

28. 28

29. • Medial ( internal ) oblique position
• Reverse the above position by inverting the
foot and elevating the hip of the affected side
enough to rotate the limb 45 degrees medially.
• Place a support under the hip if needed.
29

30. Medial oblique position
30

31. •Central ray
• Direct the central ray 5 degrees cephalad to
the knee joint at a level just below the
patellar apex.
• Structures shown:
• Anterior oblique position of the Femoral
condyles, the patella, the tibial condyles,
and the head of the fibula.
31

32. •Evaluation criteria
• Lateral (external ) oblique :
• Medial femoral and tibial condyles should be
demonstrated
• Tibial plateaus should be visualized.
• Fibula should be superimposed over the lateral
half of the tibia.
• Margin of the patella should project slightly
beyond the edge of the femoral condyle.
32

33. Lateral oblique view
33

34. • Medial ( internal ) oblique :
• Tibia and fibula should be separated at their
proximal articulation.
• Lateral condyles of the femur and tibia
should be seen.
• Both tibial plateaus should be visualized.
34

35. Medial oblique view
35

36. TUNNEL VIEW
• ALSO CALLED CAMP COVENTRY VIEW
• PA AXIAL POSITION: CAMP-COVENTRY
METHOD
• FILM: 8 * 10 inch
36

37. Position of patient
• With the patient in prone position adjust the
body such that there is no rotation.
37

38. •POSITION OF PART
• Flex the knee to an approximate 40 degree angle and
rest the foot on a suitable support.
• Center the proximal half of the cassette to the knee
joint, the central ray angulation projects the joint to the
center of the film.
• According to the preferred angle, set the protractor
arm at an angle of either 40 or 50 degrees from the
horizontal and place it beside the leg.
• Adjust the position of the foot support to place the
anterior surface of the leg parallel with the arm of the
protractor.
• Adjust the leg so that there is no medial or lateral
rotation of the knee.
38

39. •Central ray
• Tilt the tube to direct the central ray
perpendicular to the long axis of the leg and
center to the knee joint over the popliteal
depression.
• The central ray will be angled 40 degrees when
the knee is flexed 40 degrees, and 50 degrees
when the knee is flexed 50 degrees
39

40. 40

41. 41

42. TUNNEL VIEW
42

43. Evaluation criteria
• Fossa should be open and visualized.
• Posteroinferior surface of the femoral condyle should
be demonstrated.
• Intercondylar eminences and knee joint space should
be seen.
• Apex of patella should not superimpose the fossa.
• No rotation is evident by seeing slight tibiofibular
overlap.
• Soft tissue in the fossa and interspaces should be
seen.
• Bony detail on the tibial eminences, distal femur, and
proximal tibia should be demonstrated.
43

44. • An Intercondylar fossa position is usually
included in routine examinations for the knee
joint for the detection of loose bodies (joint
mice).
• The position is also used in evaluating split and
displaced cartilage in osteochondritis dissecans
and flattening or underdevelopment of the
lateral femoral condyle in congenital slipped
patella.
• It is also taken in cases of hemophilia to look
for intercondylar widening.
44

45. 45

46. PATELLA
PA VIEW
• FILM :
• 8 x 10 inch
• POSITION OF PATIENT :
• Place the patient in the prone position.
• If the knee is painful, place one sandbag under
the thigh and another under the leg to relieve
pressure on the patella.
46

47. •Position of part
• Center the cassette to the patella.
• Adjust the position of the leg to place patella
parallel with the plane of the film
• This usually requires that the heel be rotated
5 to 10 degrees laterally.
47

48. •Central ray
• Direct the central ray perpendicular to the
midpopliteal area exiting the patella.
Structures shown
• A PA projection of the patella provides sharper
detail than can be obtained in the AP position,
because of a closer part-film distance.
48

49. 49

50. •Evaluation criteria
• Adequate penetration should be present in
order to see the patella clearly through the
superimposing femur.
• There should be no rotation.
50

51. 51

52. Lateral View
• Position the patient similar to lateral knee.
• Flex the knee no more than 5 to 10 degrees.
• Increased flexion reduces the patellofemoral
joint space.
• Central ray:
• Direct the central ray perpendicular to the film,
entering the knee at the anterior margin of the
medial epicondyle.
52

53. LATERAL VIEW
53

54. OBLIQUE AXIAL VIEW
• FILM :
• 8 x 10 inch
• POSITION OF PATIENT :
• Place the patient in the prone position. Elevate the
hip of the affected side 2 or 3 inches.
• Place a sandbag under the ankle and foot and
adjust it so that the knee will be slightly flexed,
approximately 10 degrees, to relax the muscles.
54

55. •Position of part
• Center the cassette to the patella.
• With the knee turned slightly laterally from the
PA position, place the index finger against the
medial border of the patella and press it
laterally.
• Rest the knee on its anteromedial side to hold
the patella in a position of lateral displacement.
55

56. •Central ray
• Direct the central ray to the joint space between the
patella and the femoral condyles at an angle of 25 to
30 degrees caudad.
• It enters the posterior surface of the patella.
• Structures shown:
• It shows most of the patella free of superimposed
structures
• It is more comfortable for the patient, since no
pressure is placed on the injured patella
56

57. 57

58. •Evaluation criteria
• Majority of the patella should be projected
free from the femur.
• Patella and its outline where it is
superimposed by the femur should be
demonstrated
58

59. 59

60. TANGENTIAL POSITION
(AXIAL VIEWS: PATELLA)
1. Convention Inferosuperior (patient supine 45 degree
knee flexion)
2. Inferosuperior or skyline or sunrise method (patient
prone, 115 degree knee flexion)
3. Hughston method (patient prone, 55 degree knee flexion)
4. Settegast method (patient prone, 90 degree knee flexion)
5. Sitting tangential method (patient sitting, <90 degree knee
flexion)
6. Laurine method (patient supine, 20 degree
knee flexion)
7. Merchant method (patient supine, 45 degree knee
flexion, both knees)
60

61. TANGENTIAL POSITION
(AXIAL VIEWS: PATELLA)
• To obtain a tangential radiograph, the patient may be
placed in any of the following body position :
• Prone
• Supine
• Lying on the side
• Seated on the table
• Seated on the table with the leg hanging over
the edge
• Standing 61

62. • FILM :
• 8 X 10 inch
• Position of patient :
• The patient is placed in a prone or supine
position with the foot resting on the
radiographic table. The body is adjusted so
that there is no rotation.
62

63. •Position of part
• With the patient prone, slowly flex the affected knee
so that the tibia and fibula form a 50 to 60 degrees
angle from the table.
• The foot may be rested against the collimator or
supported in position
• Care must be taken to ensure the collimator surface is
not hot, as this could burn the patient.
• Adjust the leg so that there is no medial or lateral
rotation from the vertical
• Place the cassette under the knee.
63

64. •Central ray :
• The x-ray tube is angled to various degrees
cephalad based on different views and
directed through the patellofemoral joint.
• Structure shown :
• It demonstrates subluxation of the patella and
patellar fractures and allows radiologic
assessment of the femoral trochlea and
condyles.
• Preferably both knees should be examined for
comparison purposes.
64

65. 65

66. SUNRISE VIEW
66

67. HUGHSTON VIEW
67

68. SETTEGAST VIEW
68

69. SETTEGAST VARIATION
SEATED VIEW
69

70. MERCHANT VIEW
70

71. 71

72. LAURINE VIEW
72

73. •Evaluation criteria
• Patella should be seen in profile.
• Patellofemoral articulation should be open.
• Surfaces of the femoral condyles should be
visualized.
73

74. SUNRISE VIEW
74

75. MERCHANT VIEW
75

76. LAURINE VIEW
76

77. 77

78. 78