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Home Acute Trauma to the Knee
Variants
Scenario Scenario ID Procedure Adult RRL Peds RRL Appropriateness Category
Knee trauma, fall or twisting, no tenderness, no effusion, can walk, initial imaging 3073907
Radiography knee
<0.1 mSv
☢ 		<0.03 mSv [ped]
☢ 		May be appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT knee
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
Scenario Scenario ID Procedure Adult RRL Peds RRL Appropriateness Category
Knee trauma, fall or twisting, effusion, initial imaging 3183748
Radiography knee
<0.1 mSv
☢ 		<0.03 mSv [ped]
☢ 		Usually appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT knee
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
Knee trauma, fall or twisting, cannot bear weight, initial imaging 3183749
Radiography knee
<0.1 mSv
☢ 		<0.03 mSv [ped]
☢ 		Usually appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT knee
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
Knee trauma, fall or twisting, focal tenderness, initial imaging 3183747
Radiography knee
<0.1 mSv
☢ 		<0.03 mSv [ped]
☢ 		Usually appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT knee
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
Scenario Scenario ID Procedure Adult RRL Peds RRL Appropriateness Category
Knee trauma, fall or twisting, internal derangement suspected, no fracture on radiography, next imaging study 3183751
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually appropriate
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		May be appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT knee
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
Knee trauma, fall or twisting, occult fracture suspected, no fracture on radiography, next imaging study 3183750
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually appropriate
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		May be appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT knee
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
Scenario Scenario ID Procedure Adult RRL Peds RRL Appropriateness Category
Knee trauma, fall or twisting, occult fracture suspected, no fracture on radiography, next imaging study 3183787
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually appropriate
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		May be appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT lower extremity
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
Knee trauma, fall or twisting, internal derangement suspected, no fracture on radiography, next imaging study 3183788
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually appropriate
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		May be appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT lower extremity
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
Scenario Scenario ID Procedure Adult RRL Peds RRL Appropriateness Category
Knee trauma, fall or twisting, tibial plateau fracture on radiography, additional bone or soft tissue injury suspected, next imaging study 3073910
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually appropriate
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT knee
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
Scenario Scenario ID Procedure Adult RRL Peds RRL Appropriateness Category
Knee trauma, unknown mechanism, patellar tenderness, effusion, can walk, initial imaging 3079749
Radiography knee
<0.1 mSv
☢ 		<0.03 mSv [ped]
☢ 		Usually appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT knee
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
Scenario Scenario ID Procedure Adult RRL Peds RRL Appropriateness Category
Knee trauma, significant, possible dislocation, initial imaging 3079750
Radiography knee
<0.1 mSv
☢ 		<0.03 mSv [ped]
☢ 		Usually appropriate
CTA lower extremity with IV contrast
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually appropriate
Arteriography lower extremity
0.1-1mSv
☢☢ 		0.3-3 mSv [ped]
☢☢☢ 		May be appropriate
MRA knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		May be appropriate
MRI knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		May be appropriate
CT knee with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		May be appropriate
(Disagreement)
CT knee without IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		May be appropriate
US knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MR arthrography knee
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRA knee without IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
MRI knee without and with IV contrast
0 mSv
O 		0 mSv [ped]
O 		Usually not appropriate
CT knee without and with IV contrast
<0.1 mSv
☢ 		0.03-0.3 mSv [ped]
☢☢ 		Usually not appropriate
Bone scan with SPECT or SPECT/CT knee
1-10 mSv
☢☢☢ 		3-10 mSv [ped]
☢☢☢☢ 		Usually not appropriate
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