Sternoclavicular Joints PA is a radiography positioning projection of the Thorax. PA sternoclavicular joints. SID 40". The centering point is located level of T2-T3, 3 inches (7 cm) distal to the vertebra prominens (spinous process of C7), at the midsagittal plane. The central ray is perpendicular to IR at the level of T2-T3. Image-quality criteria include both sternoclavicular joints visualized and equidistant from the midline, manubrium and medial clavicles seen lateral to the column, through the ribs and lungs. A sample technique is 81 kVp with DR 3.6 or CR 7.1 mAs, at an SID of 40 inches (102 cm).
Watch the setup
All steps (2)
- The projection may also be taken erect: anterior chest against the upright Bucky, arms down by the sides.
- Align the midsagittal plane to the CR and to the midline of the grid; no rotation of the shoulders.
3D anatomy: BodyParts3D, © The Database Center for Life Science. Posed, rendered and labelled by RadTechPrepper. These animations are licensed CC BY-SA 4.0. Credits
Anatomy demonstrated
- Medial ends of both clavicles.
- Manubrium of the sternum.
- Sternoclavicular joint articulations.
Patient preparation
- Verify patient identity using two identifiers.
- Remove all radiopaque objects from the neck and chest.
- Position patient prone with a pillow, head turned to one side, arms up beside the head or down by the sides.
- The projection may also be taken erect: anterior chest against the upright Bucky, arms down by the sides.
- Align the midsagittal plane to the CR and to the midline of the grid; no rotation of the shoulders.
- Suspend respiration on expiration.
Position & centering point
Level of T2-T3, 3 inches (7 cm) distal to the vertebra prominens (spinous process of C7), at the midsagittal plane.
Central ray
Perpendicular to IR at the level of T2-T3.
Exposure / technique
- kVp
- 81
- mAs
- DR 3.6 / CR 7.1
- SID
- 40" (102 cm)
- Notes
- Grid required. Shows both joints symmetrically. Sample technique: DR 3.6 / CR 7.1 mAs at 81 kVp, 40 in SID, for a 17 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
- Both sternoclavicular joints visualized and equidistant from the midline.
- Manubrium and medial clavicles seen lateral to the column, through the ribs and lungs.
- No motion: sharp bony margins.
Common errors
- 1 Rotation of the patient moves one joint away from the midline.
- 2 Shoulders not level causes one joint to appear higher than the other.
- 3 Off-centered CR clips one or both joints from the field.
- 4 Patient slouching or leaning tilts the SC joint alignment.
- 5 Exposure not suspended on expiration, for a more uniform density.
- 6 CR not at T2-T3, 3 inches distal to the vertebra prominens.
Clinical indications
- Joint subluxation or other pathology of the sternoclavicular joints.
- Evaluation of sternoclavicular joint dislocation or subluxation.