The Double-Circle System in the Greater Tuberosity: Using Radius to Predict Rotator Cuff Tear

Area of Science:

• Orthopedic surgery
• Radiology
• Biomechanical analysis

Background:

• Rotator cuff tears are a common cause of shoulder pain and disability.
• Accurate diagnosis is crucial for effective treatment and patient outcomes.

Purpose of the Study:

• To introduce and evaluate the double-circle radius ratio as a novel diagnostic predictor for rotator cuff tears.
• To assess the morphological characteristics of the greater tuberosity of the humerus in relation to rotator cuff tears.

Main Methods:

• Retrospective analysis of 154 shoulders (112 with tears, 42 without) diagnosed via MRI.
• Measurement of humeral head and greater tuberosity radii to calculate the double-circle radius ratio.
• Statistical analysis including t-tests, chi-square tests, linear and logistic regression, and ROC curve analysis.

Main Results:

• The double-circle radius ratio was significantly higher in shoulders with rotator cuff tears (1.42 ± 0.09 vs. 1.30 ± 0.07, P=0.000).
• An ROC curve analysis showed an area under the curve of 0.846 for the ratio, with a cutoff of 1.38 yielding 70.5% sensitivity and 88.1% specificity.
• A ratio >1.38 was associated with an 11.252-fold increased odds of rotator cuff tears (P=0.000).

Conclusions:

• The double-circle radius ratio is a valuable and eligible predictor for diagnosing rotator cuff tears.
• This novel ratio offers a quantifiable method to aid in the early detection and management of rotator cuff injuries.