Editorial Commentary: Traumatic and Atraumatic Meniscal Root Injuries Can Occur Both Medially and Laterally: No Rule Without Exceptions!

It took a long time for meniscal root injuries to slowly gain scientific and clinical attention some 40 years after the first arthroscopic meniscal resection. Medial root injuries are mostly degenerative in nature and often are associated with obesity and varus deformity. However, lateral root injuries are more commonly traumatic in origin and are associated with anterior cruciate ligament injuries. But, there is no rule without an exception. Laterally, there are isolated root injuries without anterior cruciate ligament involvement and also nontraumatic root injuries that can be associated with a valgus leg axis. Traumatic medial root injuries, on the other hand, occur in the context of knee dislocations. Therefore, the therapeutic concepts should not be based strictly on the localization medial or lateral but on the etiology, traumatic and not traumatic. Even though it has been shown that many patients benefit from refixation of the meniscus root, it seems sensible to search for the etiology of nontraumatic root injuries and to integrate this into the therapeutic concept (e.g., additional osteotomy to correct the varus or valgus deformity). However, the degenerative changes in the relevant compartment must also be taken into account. Recent biomechanical results on the influence of the meniscotibial (medial) or meniscofemoral (lateral) ligaments on extrusion are also relevant with regard to the success of root refixation. These results can provide the rationale for carrying out additional centralization.