Related Experiment Video
Updated: Sep 11, 2026
Arthroscopic Management of Massive Irreparable Rotator Cuff Tears: Whole Rotator Cable Reconstruction Using Proximal Biceps Tendon Autograft
Published on: June 6, 2025
Prediction of massive rotator cuff tears classified as type B or C in the Collin classification using radiographic
Lee-Chia Liu1, Hao-Chun Chuang2, Kai-Lan Hsu1
1Department of Orthopaedic Surgery, National Cheng Kung University Hospital, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Background:
Superior humeral head migration is a feature of advanced rotator cuff tears, but conventional radiographic measurements such as the acromiohumeral interval (AHI) have limitations. Evidence predicting massive tears like Collin type B or C remains scarce. This study aimed to develop and validate the acromion-humeral angle (AHA) as a novel parameter for assessing superior humeral head migration and compare its diagnostic value with the AHI.
Methods:
The study involved a retrospective review of 65 patients with confirmed rotator cuff tears, diagnosed between 2012 and 2016, after conservative treatment had failed. Patients underwent preoperative radiographic evaluations, and surgeries were performed by a senior surgeon. Three radiological parameters were measured: the AHI; acromion-humeral angle (AHA); and its subcomponents (A1, A2). Reliability was assessed using ICC, and statistical analyses, including logistic regression and ROC curve(Receiver operating characteristic curve) analysis, were conducted to evaluate diagnostic accuracy.
Results:
The study involved an analysis of 65 participants (32 men, 33 women; mean age, 59.2 years) with 68 shoulders diagnosed with rotator cuff tears. Collin type B/C tears were observed in 27 shoulders (49.3%). Interobserver reliability for A1, A2, and AHI measurements showed excellent agreement (ICC > 0.75). Radiological evaluations and simple logistic regression indicated that the A1-A2 ratio provided the highest accuracy for detecting Collin B/C tears (AUC = 0.80, likelihood ratio = 18.06, p < 0.001. An AHI < 7.9 mm (odds ratio = 9, p < 0.001) and A1-A2 ratio > 1.52 significantly increased the likelihood of Collin B/C tears (odds ratio = 6.28, p = 0.002).
Conclusion:
The A1-A2 ratio is a reliable radiographic parameter for predicting Collin type B or C massive rotator cuff tears, with diagnostic performance comparable to the AHI. It serves as a useful alternative or complementary measure for assessing superior humeral migration. An A1-A2 ratio greater than 1.52 is associated with an approximately 6.3-fold increased risk of Collin type B or C massive rotator cuff tears.
Level Of Evidence:
III, Cohort study.
