Retrospective review of 100 consecutive shoulder MRIs evaluating patients for rotator cuff symptoms. Introduces the lateral acromion angle (LAA) — the slope of the acromion undersurface relative to the glenoid face on oblique coronal MRI — and asks whether this quantitative measurement predicts rotator cuff disease better than traditional Bigliani shape classification.
When evaluating a patient with rotator cuff symptoms on MRI, measure the LAA on the oblique coronal cut just posterior to the AC joint — an angle ≤70° should raise strong suspicion for a full-thickness tear regardless of acromion shape, and the authors suggest this threshold may justify earlier progression to subacromial decompression.
This quantitative measurement addresses a core weakness of Bigliani classification: in this study, the majority of shoulders with critically low LAAs were flat or curved acromions that would not have been flagged as high-risk by shape alone.
Retrospective review of 100 consecutive shoulder MRIs evaluating patients for rotator cuff symptoms. Introduces the lateral acromion angle (LAA) — the slope of the acromion undersurface relative to the glenoid face on oblique coronal MRI — and asks whether this quantitative measurement predicts rotator cuff disease better than traditional Bigliani shape classification.
When evaluating a patient with rotator cuff symptoms on MRI, measure the LAA on the oblique coronal cut just posterior to the AC joint — an angle ≤70° should raise strong suspicion for a full-thickness tear regardless of acromion shape, and the authors suggest this threshold may justify earlier progression to subacromial decompression.
This quantitative measurement addresses a core weakness of Bigliani classification: in this study, the majority of shoulders with critically low LAAs were flat or curved acromions that would not have been flagged as high-risk by shape alone.