The aim of this study was to systematically review clinical studies on the employed definitions of longitudinal forearm instabilities referred to as Essex-Lopresti (EL) injuries, interosseous membrane (IOM) injuries or longitudinal radioulnar dissociation.
A systematic literature search was performed in MEDLINE, Embase, CINAHL, Web of Science and Cochrane databases, adhering to PRISMA guidelines. All data on diagnosis and treatment were collected.
In total, 47 clinical studies involving 266 patients were included. Thirty-nine of 47 studies did not mention an IOM lesion as part of the EL injury. The amount of preoperative positive ulnar variance varied from >1 to >12 mm. Nine studies used some form of dynamic pre-operative or intraoperative test of longitudinal radioulnar instability.
There is no accepted definition of EL injury in the literature. In order to prevent underdetection of acute EL injury, a radial head fracture in a patient with wrist and/or forearm pain should raise awareness of the possibility of an EL injury. In this case, comparative radiographic studies and some form of dynamic assessment of longitudinal radioulnar stability should be performed.