Lateral Cervical (Swimmers) is a radiography positioning projection of the Spine. Erect lateral, arm raised, CR to T1. Twining method. The centering point is located T1, about 1 inch above the jugular notch (Bontrager). Merrill's: C7-T1 disk space, about 2 inches above the notch. Arm nearest the IR raised. The central ray is perpendicular to IR at T1. (A slight 3-5 degree caudad angle may help separate the two shoulders.). Image-quality criteria include C7 and T1 clearly visualized without shoulder overlap, C7-T1 intervertebral disc space open. A sample technique is 96 kVp with DR 28 or CR 65 mAs, at the chart's 40 in SID. The working SID is 72 inches (183 cm).
Anatomy demonstrated
- C7 (cervical vertebra prominens).
- T1 (first thoracic vertebra).
- C7-T1 intervertebral disc space.
- Cervicothoracic junction anatomy.
- Vertebral bodies and disk spaces of C5 to T3.
Patient preparation
- Trauma: do not remove the collar or move the head or neck until a physician has evaluated the horizontal-beam lateral or CT (Bontrager). Merrill's: do not move the patient's arms without permission from the attending physician and review of the lateral projection, and do not push on the shoulder.
- Verify patient identity using two identifiers.
- Remove neck jewelry and other radiopaque objects.
- Erect posture, lateral to IR.
- Raise the arm nearest the IR, flex the elbow and rest the forearm on the head.
- Depress the far shoulder and rotate it slightly posterior.
- Suspend on full expiration.
Position & centering point
T1, about 1 inch above the jugular notch (Bontrager). Merrill's: C7-T1 disk space, about 2 inches above the notch. Arm nearest the IR raised.
Central ray
Perpendicular to IR at T1. (A slight 3-5 degree caudad angle may help separate the two shoulders.)
Exposure / technique
- kVp
- 96
- mAs
- DR 28 / CR 65
- Chart row
- kVp and mAs at the chart's 40 in SID
- Working SID
- 72" (183 cm)
- Notes
- SID 60-72 inches. Arm raised overhead clears shoulder from C7-T1 region. Optional breathing technique: short even breaths during a 3-4 second exposure blur the lungs. Sample technique: DR 28 / CR 65 mAs at 96 kVp, 40 in SID, for a 24 cm part (Merrill's sample chart). Adjust for your equipment. Bontrager prints digital 90 +/- 5 kV.
kVp and mAs are sample values. Use caution when applying them in your department.
Image-quality criteria
- C7 and T1 clearly visualized without shoulder overlap.
- C7-T1 intervertebral disc space open.
- Vertebral bodies and disc spaces of C5 to T3 shown.
- No rotation evident on vertebral alignment.
- Humeral heads separated vertically.
Common errors
- 1 Arm not raised enough leaves shoulder superimposed.
- 2 Patient rotation off true lateral shifts vertebral alignment.
- 3 Far shoulder not depressed and rotated slightly posterior, so the humeral heads are not separated.
- 4 CR not centered to T1 misses the cervicothoracic junction.
Clinical indications
- Evaluation of C7-T1 region not well seen on standard lateral.
- Suspected fracture or pathology of lower cervical-thoracic junction.