Scapula Y

The Scapula Y is often used when a patient is already supine on a stretcher or cannot be easily turned to face the bucky. In this position, the patient’s back is toward the image receptor. Because the scapula is further from the board (increased OID), it is vital to ensure the patient is stabilized to maintain image sharpness.

The Goal

To demonstrate a true lateral profile of the scapula—forming the “Y”—with the humeral head superimposed over the glenoid cavity to assess for dislocation or proximal humeral fractures.

Patient Positioning (Posterior Oblique)

The Setup: Position the patient with their back against the bucky (upright or supine).
The Rotation: Rotate the patient approximately 45° to 60° away from the affected side. For example, if imaging the right shoulder, rotate the left side of the body toward the IR (LPO position).
The “Y” Alignment: Palpate the vertebral and lateral borders of the scapula. The patient is correctly rotated when the flat plane of the scapular body is perpendicular to the IR.
The Arm: In trauma cases, leave the arm in a neutral position or have the patient reach across their abdomen as far as their condition will allow. If the patient is mobile, they can place their hand on the opposite shoulder to further pull the scapula into a lateral profile.
Pro-Tip: Since the shoulder is further from the board in this view, magnification can occur. To combat this, ensure your collimation is tight and the patient is holding their breath perfectly still.

Technical Factors

Central Ray (CR): Perpendicular to the IR, centered to the scapulohumeral joint.
SID: 40″.
Collimation: Must include the acromion, coracoid process, and the entire body of the scapula down to the inferior angle.

Image Evaluation Criteria (The “Richie” Checklist)

True Lateral Scapula: The scapular body must appear as a thin, vertical line, and the ribs should not superimpose the area of interest.
The “Y” Junction: The acromion and coracoid process must form the upper branches, with the scapular body as the base.
Centering: The humeral head should be centered directly over the glenoid (the junction of the “Y”) in a non-dislocated shoulder.
Sharp Detail: Look for clear cortical margins of the scapula; if the bone looks “fuzzy,” it is likely due to the increased OID or patient motion.
Physical Marker: A lead R/L marker must be visible and placed in the lateral light field.

Why this Position Matters

This view is a lifesaver for patients on stretchers to reduce pain of moving into an awkward position. It allows you to obtain the critical “Y” view without causing further distress. It remains the gold standard for identifying the direction of a dislocation:

Anterior Dislocation: Humeral head is projected medially (toward the ribs).
Posterior Dislocation: Humeral head is projected laterally (away from the ribs).

Richie’s Pro-Tips for the AP Scapular Y

Security and Privacy: Ensure the patient is properly shielded and the door is closed. A patient who feels secure is much more likely to cooperate with the awkward rotation needed for this view.

The Angle of the Board: If the patient is supine and cannot be rotated 60 degrees, you can angle the x-ray tube instead. This “cross-table” approach requires you to angle the beam to match the plane of the scapula.

Physical Markers are Legal: Digital markers are unacceptable for trauma documentation. Always use physical lead markers to ensure the study is medically and legally valid.