Stress Radiography Is a Reliable Method to Quantify Posterior Cruciate Ligament Insufficiency: A Systematic Review

Purpose: To perform a systematic review of posterior tibial stress radiography techniques and radiographic measurement methods to compare their accuracy and efficacy to aid clinicians in quantifying posterior cruciate ligament laxity. Methods: Electronic databases, including PubMed, MEDLINE, Embase.com 1947-, Ovid Medline 1946-, Scopus 1823-, Cochrane Central Register of Controlled Trials (CENTRAL), and Clinicaltrials.gov 1997- were queried in December 2020. The abstracts of articles were reviewed by 2 authors for published studies comparing posterior tibial stress radiography techniques, describing, and comparing radiographic measurement methods, and comparing stress radiographs with instrumented knee testing. Results: The systematic review included 13 studies that satisfied the inclusion and exclusion criteria. There were 3 studies comparing stress radiography with instrumented knee devices, 6 studies comparing stress radiography techniques, and 5 studies evaluating the reliability of radiographic measurements. Stress radiography was more sensitive for detecting posterior tibial translation than KT-1000 and KT-2000 and was similar to the Rolimeter knee arthrometer. The majority of studies found TELOS stress radiography to be more sensitive than gravity or hamstring contraction stress views. Kneeling stress radiographs were found to be equivalent to TELOS in one study and superior in another. All reported methods of radiographic measurement for posterior tibial translation showed good-to-excellent intraobserver and interobserver reliability, and no single technique demonstrated clear superiority. Conclusions: The results of this systematic review indicate that posterior stress radiography with TELOS and kneeling stress radiography are the most reliable methods to evaluate posterior cruciate ligament laxity. Gravity stress and hamstring contraction can be used but may underestimate posterior tibial translation. Radiographic measurement methods are reliable and no single method is clearly superior. Clinical Relevance: This information will allow clinicians to use various radiographic methods to objectively measure posterior tibial translation to formulate a treatment plan.