Assessment of Tendon Retraction in Large to Massive Rotator Cuff Tears: A Modified Patte Classification Based on 2 Coronal Sections on Preoperative Magnetic Resonance Imaging With Higher Specificity on Predicting Reparability

Abstract

To propose a modified Patte classification (evaluating tendon retraction on 2 coronal sections) and analyze whether this classification was better at predicting irreparability and retear of large to massive rotator cuff tears (RCTs). A retrospective study was performed. Imaging evaluation including tendon retraction, fatty infiltration, the acromiohumeral distance (AHD), and the tangent sign was performed using magnetic resonance imaging. The modified Patte classification was used to assess tendon retraction. Intraobserver and interobserver reliability was analyzed by calculating intraclass correlation coefficients. Factors affecting irreparability and retear were analyzed using both univariate and multivariate analyses. Sensitivity and specificity of tendon retraction to predict irreparability and retear were calculated. A total of 121 shoulders with large to massive RCTs underwent arthroscopic rotator cuff repairs. The modified Patte classification system had excellent interobserver and intraobserver reliability. Several factors were associated with reparability and retear in the univariate analysis. However, in binary logistic regression analysis, the only factors affecting reparability were AHD less than 0.4 cm (P= .007) and modified Patte stage III tendon retraction (P=.023). Low-grade repair quality (P= .001) and modified Patte stage III tendon retraction (P= .031) were independent factors for retear. Modified Patte stage III had a high specificity for predicting irreparability (93.58%) and retear (98.78%), whereas the specificity of original Patte stage III was 76.15% and 84.15%, respectively. For large to massive RCT repairs, modified Patte stage III tendon retraction with evaluation of 2 coronal cuts reveals higher specificity on predicting tendon irreparability and postoperative retear. An AHD less than 0.4 cm on magnetic resonance imaging and modified Patte stage III tendon retraction were independent risk factors for irreparability. Low-grade repair quality and modified Patte stage III tendon retraction were independent risk factors for postoperative retear. Level III, case-control study.