The critical shoulder angle is associated with osteoarthritis in the shoulder but not rotator cuff tears: a retrospective case-control study

Relationship Between the Critical Shoulder Angle and Shoulder Disease

“…In an effort to overcome this limitation, Spiegl et al 22 developed a method for measuring the CSA with use of a coronal T1-weighted oblique MRI scan, but they found that using conventional radiography according to the method described by Moor et al 6 was more accurate and reproducible than using MRI. Other authors 23 have found that radiographs showing anterior-to-posterior glenoid rim overlap of .11 mm are an indication of .20°of malrotation as defined by Moor et al 6 . However, as shown by Suter et al 20 , much of the recent research on the CSA may be invalid if only 5°to 8°of change in anteversion or retroversion, instead of the previously accepted 20°of change, can affect the accuracy of measurements.…”

“…The initial evaluations of the CSA in the literature indicated that normal values were between 30°and 35°, with values of ,30°being implicated in the development of glenohumeral osteoarthritis and values of .35°being considered a risk factor for rotator cuff tears 6,[23][24][25][26] . In their original study, Moor et al 6 evaluated the CSA in a control group of 94 asymptomatic shoulders with normal rotator cuff musculature and no osteoarthritis, 102 shoulders with MRIdocumented full-thickness rotator cuff tears and no osteoarthritis, and 102 shoulders with primary osteoarthritis and no cuff tears noted during shoulderreplacement surgery.…”

“…While the study established a high sensitivity and specificity for the CSA in relation to osteoarthritis, its retrospective nature limited its ability to show causation between CSA and osteoarthritis. Recently, Bjarnison et al 23 reported that the CSA was associated with shoulder osteoarthritis but not rotator cuff tears. The authors reported an odds ratio for the development of osteoarthritis of 2.25 for patients with a CSA of ,30°(p 5 0.002), whereas the odds ratio for the development of a cuff tear was 1.12 for patients with a CSA of .35°(p 5 0.63).…”

Critical shoulder angle is an effective radiographic parameter that is associated with rotator cuff tears and osteoarthritis: a systematic review

“…One study (n=298) determined that of the patients with a CSA <30°, 93% had osteoarthritis 8. One study (n=724) determined that the OR for developing osteoarthritis in those with a CSA <30° was 2.25 (p=0.002) 35. Lastly, one study (n=50) found no difference in mean CSA between patients with osteoarthritis versus those with massive rotator cuff tears10 (online supplementary appendix table 2).…”

Rotator Cuff Tears : Short- and long-term aspects on treatment outcome

“…The most common way is called the Critical Shoulder Angle (CSA), and measures the angle between the glenoid and the most lateral part of the acromion 194 . Larger CSA has been found to be associated with an increased risk of rotator cuff disease in some studies 166,194 , but not all studies have support for this association 25 . There are also other measures of the bony anatomy that may indicate an increased risk of rotator cuff tear, such as the greater tuberosity angle 58 and the Y-, G-and R-angles 233 .…”