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Appropriateness Criteria

Variant 1: Follow-up of symptomatic or asymptomatic patients with a total knee arthroplasty. Initial imaging.
Procedure Appropriateness Category SOE Adult RRL Peds RRL Rating Median Final Tabulations
1 2 3 4 5 6 7 8 9
Radiography knee Usually appropriate Strong ☢ <0.1 mSv ☢ <0.03 mSv [ped] 9 9 0 0 0 0 0 0 0 0 11
References Study Quality
42 (7871170) 4
41 (31954608) 3
40 (15864052) 3
39 (16980893) 3
38 (16672885) 4
37 (16958475) 4
36 (14566740) 3
35 (19826813) 2
34 (20218424) 3
33 (14658097) 4
32 (15284990) 4
31 (16485456) 4
30 (18310744) 4
29 (15837396) 4
28 (16595481) 4
27 (8713906) 4
26 (19057730) 4
25 (34017659) 3
24 (21641179) 2
23 (32490778) 4
22 (16846767) 4
21 (24370168) 4
20 (16514580) 4
19 (18612008) 4
18 (8895629) 3
4 (24261390) 4
US knee Usually not appropriate Expert Consensus O 0 mSv O 0 mSv [ped] 1 1 10 1 0 0 0 0 0 0 0
Fluoroscopy knee Usually not appropriate Expert Consensus ☢ <0.1 mSv 1 1 11 0 0 0 0 0 0 0 0
Image-guided aspiration knee Usually not appropriate Expert Consensus Varies Varies 1 1 11 0 0 0 0 0 0 0 0
MRI knee without and with IV contrast Usually not appropriate Expert Consensus O 0 mSv O 0 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
MRI knee without IV contrast Usually not appropriate Expert Consensus O 0 mSv O 0 mSv [ped] 1 1 10 1 0 0 0 0 0 0 0
CT arthrography knee Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
CT knee with IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
CT knee without and with IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
CT knee without IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
3-phase bone scan knee Usually not appropriate Expert Consensus ☢☢☢ 1-10 mSv 1 1 11 0 0 0 0 0 0 0 0
FDG-PET/CT whole body Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
Fluoride PET/CT whole body Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
WBC scan and sulfur colloid scan knee Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv 1 1 11 0 0 0 0 0 0 0 0
Variant 2: Suspected infection after total knee arthroplasty. Additional imaging following radiographs.
Procedure Appropriateness Category SOE Adult RRL Peds RRL Rating Median Final Tabulations
1 2 3 4 5 6 7 8 9
Image-guided aspiration knee Usually appropriate Strong Varies Varies 9 9 1 0 0 0 0 0 0 2 8
References Study Quality
92 (21776555) 4
91 (34587890) 3
90 (17823024) 3
89 (9418615) 3
88 (16520210) 3
87 (16434514) 4
86 (15465503) 3
85 (14658109) 3
84 (8836084) 3
83 (21427339) 4
54 (-3195822) 4
50 (15307559) 3
49 (12164519) 3
47 (16224857) 4
46 (17918072) 2
45 (12168179) 2
44 (19692690) 4
30 (18310744) 4
18 (8895629) 3
US knee May be appropriate Expert Consensus O 0 mSv O 0 mSv [ped] 4 4 0 1 3 3 2 1 1 0 0
MRI knee without and with IV contrast May be appropriate Strong O 0 mSv O 0 mSv [ped] 6 6 0 0 0 0 2 4 5 0 0
References Study Quality
22 (16846767) 4
97 (16950034) 3
96 (16627160) 4
95 (27232641) 2
94 (23091176) 2
93 (26295591) 4
MRI knee without IV contrast May be appropriate Strong O 0 mSv O 0 mSv [ped] 5 5 1 0 0 1 4 2 2 1 0
References Study Quality
22 (16846767) 4
97 (16950034) 3
96 (16627160) 4
95 (27232641) 2
94 (23091176) 2
93 (26295591) 4
CT knee with IV contrast May be appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 4 4 3 0 2 3 3 0 0 0 0
3-phase bone scan knee May be appropriate Strong ☢☢☢ 1-10 mSv 5 5 0 1 0 1 5 1 2 0 1
References Study Quality
66 (-3195824) 4
65 (25071885) 4
64 (19038601) 4
63 (19182727) 4
62 (2225613) 3
61 (2354603) 2
60 (11247700) 3
59 (22361912) 4
30 (18310744) 4
18 (8895629) 3
WBC scan and sulfur colloid scan knee May be appropriate Strong ☢☢☢☢ 10-30 mSv 6 6 0 0 0 1 4 1 4 1 0
References Study Quality
109 (-3195826) 3
108 (31218592) 3
107 (2027967) 3
106 (11547374) 3
105 (17138732) 2
104 (10810483) 3
103 (9785394) 4
102 (2208853) 3
101 (8496202) 3
100 (10794224) 3
99 (15001684) 2
98 (3733846) 4
69 (15534056) 3
66 (-3195824) 4
64 (19038601) 4
63 (19182727) 4
50 (15307559) 3
49 (12164519) 3
Fluoroscopy knee Usually not appropriate Limited ☢ <0.1 mSv 1 1 8 0 2 0 1 0 0 0 0
References Study Quality
30 (18310744) 4
CT arthrography knee Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 9 1 0 0 0 1 0 0 0
CT knee without and with IV contrast Usually not appropriate Limited ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 6 1 1 2 1 0 0 0 0
References Study Quality
20 (16514580) 4
67 (17080648) 3
CT knee without IV contrast Usually not appropriate Limited ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 3 3 4 0 2 3 2 0 0 0 0
References Study Quality
20 (16514580) 4
67 (17080648) 3
FDG-PET/CT whole body Usually not appropriate Strong ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 3 3 1 2 3 3 2 0 0 0 0
References Study Quality
82 (11685492) 2
81 (24873788) 2
80 (12271415) 3
79 (16721569) 4
78 (17448973) 3
77 (-3195825) 4
76 (12766596) 3
75 (16829764) M
74 (16512924) 3
73 (18704405) M
72 (32145890) 4
71 (12089487) 3
70 (24196917) 3
69 (15534056) 3
68 (11197979) 3
Fluoride PET/CT whole body Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
Variant 3: Pain after total knee arthroplasty. Infection excluded. Suspect aseptic loosening or osteolysis or instability. Additional imaging following radiographs.
Procedure Appropriateness Category SOE Adult RRL Peds RRL Rating Median Final Tabulations
1 2 3 4 5 6 7 8 9
MRI knee without IV contrast Usually appropriate Limited O 0 mSv O 0 mSv [ped] 7 7 0 0 0 1 0 2 4 2 2
References Study Quality
131 (35315718) 2
116 (25633024) 4
97 (16950034) 3
96 (16627160) 4
93 (26295591) 4
22 (16846767) 4
CT knee without IV contrast Usually appropriate Limited ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 7 7 0 0 0 0 1 0 5 3 2
References Study Quality
20 (16514580) 4
67 (17080648) 3
116 (25633024) 4
124 (16514583) 4
125 (15993602) 4
3-phase bone scan knee May be appropriate Strong ☢☢☢ 1-10 mSv 5 5 1 1 0 2 6 1 0 0 0
References Study Quality
123 (3655908) 3
122 (31263926) 3
121 (11553828) 4
120 (14579084) 3
119 (2295172) 3
66 (-3195824) 4
62 (2225613) 3
61 (2354603) 2
60 (11247700) 3
20 (16514580) 4
US knee Usually not appropriate Limited O 0 mSv O 0 mSv [ped] 1 1 8 1 2 0 0 0 0 0 0
References Study Quality
132 (18751851) 4
133 (27726755) 4
Fluoroscopy knee Usually not appropriate Limited ☢ <0.1 mSv 3 3 3 0 5 2 0 1 0 0 0
References Study Quality
20 (16514580) 4
129 (8895643) 4
130 (2793887) 4
MRI knee without and with IV contrast Usually not appropriate Expert Consensus O 0 mSv O 0 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
CT arthrography knee Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 2 2 5 2 1 2 1 0 0 0 0
CT knee with IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 10 1 0 0 0 0 0 0 0
CT knee without and with IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 10 1 0 0 0 0 0 0 0
FDG-PET/CT whole body Usually not appropriate Limited ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 6 1 3 0 1 0 0 0 0
References Study Quality
126 (27468360) 4
121 (11553828) 4
78 (17448973) 3
74 (16512924) 3
66 (-3195824) 4
127 (15100514) 2
Fluoride PET/CT whole body Usually not appropriate Limited ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 9 0 1 1 0 0 0 0 0
References Study Quality
128 (31040911) 3
WBC scan and sulfur colloid scan knee Usually not appropriate Strong ☢☢☢☢ 10-30 mSv 3 3 3 1 2 3 2 0 0 0 0
References Study Quality
66 (-3195824) 4
134 (2266391) 3
127 (15100514) 2
109 (-3195826) 3
107 (2027967) 3
106 (11547374) 3
101 (8496202) 3
Variant 4: Pain after total knee arthroplasty. Suspect periprosthetic or hardware fracture. Additional imaging following radiographs.
Procedure Appropriateness Category SOE Adult RRL Peds RRL Rating Median Final Tabulations
1 2 3 4 5 6 7 8 9
CT knee without IV contrast Usually appropriate Limited ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 8 8 1 0 0 0 0 0 2 3 5
References Study Quality
20 (16514580) 4
MRI knee without IV contrast May be appropriate Limited O 0 mSv O 0 mSv [ped] 6 6 0 0 1 0 3 2 1 3 1
References Study Quality
22 (16846767) 4
3-phase bone scan knee May be appropriate Limited ☢☢☢ 1-10 mSv 4 4 3 1 1 2 4 0 0 0 0
References Study Quality
137 (22733959) 4
138 (24647514) 4
US knee Usually not appropriate Expert Consensus O 0 mSv O 0 mSv [ped] 1 1 8 1 1 1 0 0 0 0 0
Fluoroscopy knee Usually not appropriate Expert Consensus ☢ <0.1 mSv 1 1 11 0 0 0 0 0 0 0 0
MRI knee without and with IV contrast Usually not appropriate Expert Consensus O 0 mSv O 0 mSv [ped] 1 1 10 1 0 0 0 0 0 0 0
CT arthrography knee Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 10 1 0 0 0 0 0 0 0
CT knee with IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
CT knee without and with IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
FDG-PET/CT whole body Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
Fluoride PET/CT whole body Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
WBC scan and sulfur colloid scan knee Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv 1 1 10 1 0 0 0 0 0 0 0
Variant 5: Pain after total knee arthroplasty. Measuring component rotation. Additional imaging following radiographs.
Procedure Appropriateness Category SOE Adult RRL Peds RRL Rating Median Final Tabulations
1 2 3 4 5 6 7 8 9
CT knee without IV contrast Usually appropriate Strong ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 9 9 0 0 0 0 0 0 0 2 9
References Study Quality
20 (16514580) 4
145 (30473230) 3
144 (23906867) 2
143 (7497664) 2
142 (11021452) 3
140 (11689376) 4
139 (9917679) 3
40 (15864052) 3
MRI knee without IV contrast May be appropriate Limited O 0 mSv O 0 mSv [ped] 6 6 0 0 1 0 4 4 1 0 1
References Study Quality
148 (22933492) 3
147 (21741843) 4
146 (10794232) 4
US knee Usually not appropriate Expert Consensus O 0 mSv O 0 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
Fluoroscopy knee Usually not appropriate Expert Consensus ☢ <0.1 mSv 1 1 8 2 1 0 0 0 0 0 0
MRI knee without and with IV contrast Usually not appropriate Expert Consensus O 0 mSv O 0 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
CT arthrography knee Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
CT knee with IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
CT knee without and with IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
3-phase bone scan knee Usually not appropriate Expert Consensus ☢☢☢ 1-10 mSv 1 1 11 0 0 0 0 0 0 0 0
FDG-PET/CT whole body Usually not appropriate Limited ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 10 0 1 0 0 0 0 0 0
References Study Quality
79 (16721569) 4
Fluoride PET/CT whole body Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
WBC scan and sulfur colloid scan knee Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv 1 1 10 1 0 0 0 0 0 0 0
Variant 6: Pain after total knee arthroplasty. Suspect periprosthetic soft-tissue abnormality unrelated to infection, including quadriceps or patellar tendinopathy (quadriceps or patellar tendon tears, postoperative arthrofibrosis, patellar clunk syndrome, or impingement of nerves or other soft tissues). Additional imaging following radiographs.
Procedure Appropriateness Category SOE Adult RRL Peds RRL Rating Median Final Tabulations
1 2 3 4 5 6 7 8 9
US knee Usually appropriate Limited O 0 mSv O 0 mSv [ped] 7 7 0 0 0 0 2 2 4 2 1
References Study Quality
160 (27613578) 4
159 (2273390) 4
158 (14736658) 3
157 (17543487) 4
156 (32803377) 4
155 (29395745) 2
MRI knee without IV contrast Usually appropriate Limited O 0 mSv O 0 mSv [ped] 8 8 0 0 0 0 0 0 2 5 4
References Study Quality
93 (26295591) 4
154 (27022733) 4
153 (32993344) 3
152 (12579011) 4
147 (21741843) 4
Fluoroscopy knee Usually not appropriate Expert Consensus ☢ <0.1 mSv 1 1 11 0 0 0 0 0 0 0 0
MRI knee without and with IV contrast Usually not appropriate Expert Consensus O 0 mSv O 0 mSv [ped] 1 1 7 3 1 0 0 0 0 0 0
CT arthrography knee Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 9 0 2 0 0 0 0 0 0
CT knee with IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 10 0 1 0 0 0 0 0 0
CT knee without and with IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
CT knee without IV contrast Usually not appropriate Expert Consensus ☢ <0.1 mSv ☢☢ 0.03-0.3 mSv [ped] 1 1 6 1 1 3 0 0 0 0 0
3-phase bone scan knee Usually not appropriate Expert Consensus ☢☢☢ 1-10 mSv 1 1 10 1 0 0 0 0 0 0 0
FDG-PET/CT whole body Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
Fluoride PET/CT whole body Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv ☢☢☢☢ 3-10 mSv [ped] 1 1 11 0 0 0 0 0 0 0 0
WBC scan and sulfur colloid scan knee Usually not appropriate Expert Consensus ☢☢☢☢ 10-30 mSv 1 1 11 0 0 0 0 0 0 0 0
Appendix Key

A more complete discussion of the items presented below can be found by accessing the supporting documents at the designated hyperlinks.

Appropriateness Category:The panel’s recommendation for a procedure based on the assessment of the risks and benefits of performing the procedure for the specified clinical scenario.

SOE: Strength of Evidence. The assessment of the amount and quality of evidence found in the peer reviewed medical literature for an appropriateness recommendation.

  • References: The citation number and PMID for the reference(s) associated with the recommendation.
  • Study Quality: The assessment of the quality of an individual reference based on the number of study quality elements described in the reference.

RRL: Relative Radiation Level. A population based assessment of the amount of radiation a typical patient may be exposed to during the specified procedure.

Rating: The final rating (1-9 scale) for the procedure as determined by the panel during rating rounds.

Median: The median rating (1-9 scale) for the procedure as determined by the panel during rating rounds.

Final tabulations: A histogram showing the number of panel members who rated the procedure as noted in the column heading (ie, 1, 2, 3, etc.).

Additional supporting documents about the AC methodology and processes can be found at www.acr.org/ac.