LAUSR

We read the recent article titled “A new scoring system for prediction of meniscal repair in traumatic meniscal tears [10]” in Knee Surgery, Sports Traumatology, Arthroscopy with lots of enthusiasm. We have a few comments regarding the study. This study is the first of its kind and any clarification would increase the readers’ understanding, as well as the reproducibility in other centers. The study was done in two parts; retrospective and prospective. The retrospective part was used to develop the scoring method. This section lacks statistical and sample selection details. In our opinion, it is difficult to find all patients in either group (meniscectomy vs meniscal repair) to have had identifiable tears on MRI, as the sensitivity of the MRI is low. The sensitivity of MRI in detecting meniscal tears varies from 47 to 88% [3, 4, 7, 9]. Most of the published studies have demonstrated difficulty in predicting the reparability of tears based on MRI [4, 6, 11] except the recent one which had predicted the reparability based on calculating the distance from capsular junction to the tear [7]. Even in the current study, the authors had difficulty in predicting the lateral meniscal tear reparability and reasoned it was due to low MRI sensitivity. It is hard to identify all the meniscal tears with MRI and it’s even harder to classify them accurately. The authors did not state whether there was identifiable tear in all the 120 consecutive patients. It was mentioned proton density fat-saturated, T1-weighted, and T2-weighted images were used in sagittal, coronal, and axial sequences to study the meniscal injuries however the authors did not specify which sequence or cut was used to classify the zones. The zone may change depending on the level of cut in complex tears and even in example cases 1 and 2, the cut levels were different. The zones were described as R–R, R–W, W–W which were arthroscopic/anatomic classification. The vascularity based classification had shown to be highly variable [1, 2]. It would be useful to the readers if the authors could explain their MRI technique as well as the MRI based classification system used in the study in detail as it is the cornerstone of the study. Authors have also stated, ‘associated anterior cruciate ligament (ACL) injury, mechanism of injury, length of tear on MRI, etc. were considered initially, but were not found to have a statistically significant correlation’. However, they did not provide the statistical p value for all the parameters they have studied, including ACL injury in Table 1. In part 1 of the study, associated ACL injury may not have reached its significance due to small sample size. It could have been verified in the prospective part as many studies have shown increased reparability when medial meniscus tear was associated with ACL injury as well as better healing rates [5, 6, 8, 12]. In the study, it was mentioned that “The incorrect predictions in lateral meniscus tears in our study have been four cases out 65 lateral meniscus tears” which we believe to be incorrect. It should have been 15 out of 65 as per Table 4. If authors meant four cases of false positives that were not identifiable in MRI in lateral meniscectomy group, then the readers may be interested in knowing the indication for arthroscopy in those cases. The demographic data of patients were also missing which may have bearing on decision making. Having patients on either extreme of age will make the predictability higher and most of the dilemma occurs only in borderline cases. Besides, the surgeons’ competence in repairing complex tears can also influence the results. This comment refers to the article available online at https ://doi. org/10.1007/s0016 7-019-05377 -7.