This systematic review examines whether the critical shoulder angle (CSA), a radiographic measure of scapular morphology, relates to rotator cuff disease. It asks two questions: does a larger CSA increase the incidence of chronic full-thickness tears, and does it affect outcomes after rotator cuff repair? Twelve comparative studies (Level II-IV) were pooled qualitatively.
The clinical takeaway is that CSA is an interesting risk marker, not a decision tool. A larger CSA correlates with tears and predicts a higher re-tear rate, but it does not change what matters most to your patient: functional outcome after repair.
Diagnosis of a rotator cuff tear stays firmly rooted in exam findings. Supraspinatus weakness plus external rotation weakness plus impingement gives a 98% post-test probability, which outperforms any single radiographic measure.
The re-tear association has fueled interest in lateral acromioplasty to reduce the CSA at surgery. Be skeptical here. The authors draw a direct parallel to anterior acromioplasty, once thought essential but later shown to add nothing. Only one uncontrolled study supports CSA correction.
Given poor study quality and the fact that most radiographs cannot even be reliably measured, treat CSA as a topic to know for boards rather than a number to act on tomorrow.
This systematic review examines whether the critical shoulder angle (CSA), a radiographic measure of scapular morphology, relates to rotator cuff disease. It asks two questions: does a larger CSA increase the incidence of chronic full-thickness tears, and does it affect outcomes after rotator cuff repair? Twelve comparative studies (Level II-IV) were pooled qualitatively.
The clinical takeaway is that CSA is an interesting risk marker, not a decision tool. A larger CSA correlates with tears and predicts a higher re-tear rate, but it does not change what matters most to your patient: functional outcome after repair.
Diagnosis of a rotator cuff tear stays firmly rooted in exam findings. Supraspinatus weakness plus external rotation weakness plus impingement gives a 98% post-test probability, which outperforms any single radiographic measure.
The re-tear association has fueled interest in lateral acromioplasty to reduce the CSA at surgery. Be skeptical here. The authors draw a direct parallel to anterior acromioplasty, once thought essential but later shown to add nothing. Only one uncontrolled study supports CSA correction.
Given poor study quality and the fact that most radiographs cannot even be reliably measured, treat CSA as a topic to know for boards rather than a number to act on tomorrow.