Yang JS, Liu P, Liu TJ, et al. - A clinical case series.was performed to propose a novel posterior ligament-bone injury classification and severity (PLICS) score system that can be applied to reflect the severity of subaxial cervical fracture-dislocations and prognosticate the failure of anterior-only surgery, and to assess the intraobserver and interobserver reliability of this system. Ten individuals were assigned randomly for intraobserver reliability assessment on two separate occasions, one month apart. Researchers further randomly selected another 30 patients, and the interobserver reliability was measured by comparing results of each case between each reviewer and averaging. In the analysis, 354 patients who fulfilled the follow-up were classified into stable and unstable groups according to whether radiologically stable was observed during follow-up to examine the difference in the PLICS score. According to the findings, the proposed PLICS score system exhibited excellent intraobserver and interobserver reliability. After an anterior-only reconstruction, the risk of postoperative failure is high, and supplemental posterior strengthening can be considered when a PLICS score is > 7 or 7 accompanied by extremely unstable lateral mass fractures.