Increased Posterior Tibial Slope and Meniscal Slope Could Be Risk Factors for Meniscal Injuries: A Systematic Review

Purpose: The purpose of this systematic review was to summarize the available evidence and examine the relation between the posterior tibial slope (PTS) and meniscal slope (MS) and the incidence of meniscal injury. Methods: PubMed, Embase, the Cochrane Central Register of Controlled Trials, and Web of Science were searched from inception to February 23, 2021. Cohort studies investigating the association between PTS or MS and the risk of meniscal injury were included. Two authors independently conducted the literature search, data extraction, and quality assessment. Results: Sixteen studies with a total of 2,670 patients were included. For meniscal injury with an anterior cruciate ligament tear, the lateral PTS in the lateral meniscal root tear group (range, 8.0 degrees-12.6 degrees) was significantly higher than that in the control group (range, 4.0 degrees-10.7 degrees). Furthermore, there appeared to be a relation between a greater medial MS and the presence of a ramp lesion (range, 2.6 degrees-6.7 degrees for ramp lesion vs 2.0 degrees-5.1 degrees for control). For degenerative meniscal injury, the medial PTS in the medial meniscal posterior root tear group (range, 6.15 degrees-10.4 degrees) was significantly greater than that in the control group (range, 4.0 degrees-9.8 degrees). Conclusions: On the basis of the available evidence, for meniscal injury with an anterior cruciate ligament tear, an increased lateral PTS was associated with a higher risk of lateral meniscal tears and lateral meniscal posterior root tears. Furthermore, there appeared to be a relation between an increased medial MS and a higher risk of ramp lesions. For degenerative meniscal injury, most of the included studies showed that a larger medial PTS could increase the risk of medial meniscal tears and medial meniscal posterior root tears.