MRI sternoclavicluar joint

Hello-

Which CPT® code would best describe MRI sternoclavicluar joint?

Would it be 73221-Magnetic resonance (eg, proton) imaging, any joint of upper extremity; without contrast material(s) or 71550 Magnetic resonance (eg, proton) imaging, chest (eg, for evaluation of hilar and mediastinal lymphadenopathy); without contrast material(s)?

Any thoughts?

Thank you,
Caroline