Sternoclavicular Joints PA Oblique is a radiography positioning projection of the Thorax. PA oblique SC joints, 10-15 degrees. SID 40". The centering point is located level of T2-T3, 1 to 2 inches lateral to the midsagittal plane, toward the upside. The central ray is perpendicular to IR at the level of T2-T3. Image-quality criteria include affected sternoclavicular joint clearly visualized and open, down-side joint next to the spine, not superimposed on the vertebral column or manubrium. A sample technique is 81 kVp with DR 5 or CR 10 mAs, at an SID of 40 inches (102 cm).
Anatomy demonstrated
- Medial end of the affected clavicle.
- Manubrium of the sternum.
- Sternoclavicular joint articulation.
Patient preparation
- Verify patient identity using two identifiers.
- Remove all radiopaque objects from the neck and chest.
- Position patient prone (or erect) in a 10-15 degree anterior oblique, raising the side away from the IR.
- Affected side down, closest to the IR.
- Suspend respiration on expiration.
Position & centering point
Level of T2-T3, 1 to 2 inches lateral to the midsagittal plane, toward the upside.
Central ray
Perpendicular to IR at the level of T2-T3.
Exposure / technique
- kVp
- 81
- mAs
- DR 5 / CR 10
- SID
- 40" (102 cm)
- Notes
- Grid required. 10-15 degree obliquity shows the downside joint next to the spine. Sample technique: DR 5 / CR 10 mAs at 81 kVp, 40 in SID, for an 18 cm part (Merrill's sample chart). Adjust for your equipment.
kVp and mAs are sample values. Use caution when applying them in your department.
Image-quality criteria
- Affected sternoclavicular joint clearly visualized and open.
- Down-side joint next to the spine, not superimposed on the vertebral column or manubrium.
- Medial clavicular end and sternum articulation sharply defined.
- Upside sternoclavicular joint foreshortened.
- No motion: sharp bony margins.
- 10-15 degrees of rotation for the downside joint; 5-10 degrees shows the upside joint next to the spine.
Common errors
- 1 Less than 10 degrees of rotation shows the upside joint next to the spine, not the downside joint.
- 2 Affected side not closest to the IR prevents visualization of the target joint.
- 3 CR not at T2-T3, 1 to 2 inches lateral toward the upside.
Clinical indications
- Detailed evaluation of SC joint dislocation or subluxation.
- Joint separation, subluxation or other pathology of the SC joints.