Traumatic and non-traumatic isolated horizontal meniscal tears of the knee in patients less than 40 years of age

Purpose: The aim of this study is to analyze the characteristics of isolated horizontal meniscal tears in young patients and compared traumatic and non-traumatic isolated horizontal meniscal tear without other type of meniscal tear. Methods: Forty patients who underwent partial meniscectomy with isolated horizontal meniscal tears and followed up for more than 2 years were divided into two groups according to the presence of distinct previous traumatic events (defined as contusion or sprain) to the knees. Analyzed variables included in this descriptive statistics were involved side of knee and location of meniscus, physical examinations (joint line tenderness and McMurray's testing), subjective International Knee Documentation Committee (IKDC) criteria, and Lysholm functional questionnaires. Results: Twenty-two of the forty patients (55 %) had distinct previous traumatic events. Fourteen cases (63.6 %) in traumatic group and 14 cases (77.8 %) in non-traumatic group are involved non-dominant knees during locomotion or playing sports. Twenty patients (90.9 %) in traumatic group and eight patients (44.4 %) in non-traumatic group presented with tear in the midportion of the medial meniscus on arthroscopic findings (p < 0.01). Six patients (60.0 %) in traumatic group and twelve patients (85.7 %) in non-traumatic group had meniscal cysts on arthroscopic findings at the time of surgery (p < 0.01). There was no statistic difference between the two groups with respect to physical examinations, subjective IKDC scores, and Lysholm functional scores. Conclusions: Isolated horizontal meniscal tears in young patients predominantly involved non-dominant knees and medial meniscus. Anterior aspect of medial meniscus was more frequently involved in traumatic group. Meniscal cysts were more frequently showed in non-traumatic group. © 2012 Springer-Verlag.