Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA
The Posterolateral Instability Score (PoLIS) of the knee joint: a guideline for standardized documentation, classification, and surgical decision-making
Abstract
There has been a recent resurgence in interest in posterolateral instabilities of the knee joint. As this terminology comprises a large variety of pathologies, confusion and ambiguity in communication between surgeons and allied health professionals are generated. Consequently, accurate classification criteria are required to account for thorough preoperative diagnostics, surgical decision-making, and a standardized scientific documentation of injury severity.
A working group of five knee surgeons, who retrospect more than 2000 reconstructions of the posterolateral corner (PLC) at the minimum, was founded. An advanced PubMed search was conducted to identify key definitions. After defining an accurate diagnostic work-up, popular consensus was reached on definitions and covariates for a novel classification, rating of injury severity, and the resulting surgical decision-making.
Three columns (lateral instability, cruciate ligament involvement, and relevant covariates), each ranging from A to D with increasing severity and assigning a number of points, were needed to meet the requirements. The generated terminology translated into the Posterolateral Instability Score (PoLIS) and the added number of points, ranging from 1 to 18, depicted the injury severity score.
The presented classification may enable an objective assessment and documentation of the injury severity of the inherently complex pathology of injuries to the lateral side of the knee joint.
V.
Source and rights
Published by Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA, 2021. The guideline itself is at the source linked here.
Prognia summarises this guideline for reference and education. It is not medical advice. Always check the official guideline and current local protocols before acting on it.







