Intra-articular Patterns of Bucket Handle Meniscal Tears and Its Relation to Reducibility

Abstract

Background: The purpose of this study was to assess the intra-articular patterns in the rotational deformities of bucket handlemeniscal tears (BHMTs) based on arthroscopic fi ndings and their clinical relevance. Methods: From 2004 to 2009, 42 patients with a BHMT diagnosed by magnetic resonance imaging underwent arthroscopic surgery. The arthroscopic data (all procedures were recorded) were evaluated retrospectively, and BHMTs were classifi ed accordingto the rotational directions of centrally displaced fragments. To assess the reliability of the agreement in this classifi cation, 2orthopedic surgeons re-classifi ed BHMTs, 1 week after fi rst trial. Intra- and interobserver reliabilities were assessed using kappastatistics. In addition, we address specifi c tear patterns, associated anterior cruciate ligament injury, medio-lateral difference, reducibility,chronicity, and reparability. Results: Most of the tears could be categorized into one of 3 morphologic patterns. Of the tears, 4.8% could not be categorized. BHMTs were classifi ed, based on the rotational directions of centrally displaced fragments, as follows; the upward rotation group(type 1), the downward rotation group (type 2) and the reverse group (type 3). The most common intra-articular pattern was type1 (29 patients, 69%). The occurrence of the other patterns was: type 2 in 7 patients (16.7%), type 3 in 4 patients (9.5%); we werenot able to make a classifi cation of type in 2 patients (4.8%). Intra-observer reliability was 0.86 in terms of kappa statistics, whichimplies almost perfect agreement. Mean interobserver reliability (0.73) showed substantial agreement. Type 1 and 2 tears wereeasily reduced, whereas all type 3 tears (4/4) needed additional procedures to achieve reduction. Conclusions: Based on arthroscopic findings, we describe a comprehensive BHMT classification scheme that encompasses95.2% of all tears. Tear type was correlated with reducibility.