BACKGROUND The classification and therapeutic strategy for thoracolumbar burst fractures are controversial. The load-sharing classification (LSC) and thoracolumbar injury classification system (TLICS) are both quantitative evaluation systems for thoracolumbar burst fractures. We hypothesized that their combination would be helpful not only for surgical indications but also for deciding on the surgical approach. However, no reports have evaluated the relationship between them. The purpose of this study was to clarify the relationship between the LSC and TLICS and investigate the clinical usefulness of their combination. METHODS This study included 100 consecutive patients surgically treated for thoracolumbar burst fractures (71 men and 29 women; mean age 36 years). Clinical and radiographical data as well as thoracolumbar injury classification systems were evaluated. RESULTS LSC and TLICS scores were found to be statistically correlated. The mean LSC score with a TLICS score of 5 or more (surgical treatment recommended) was 7.3 ± 1.2 points, and the mean LSC score with a TLICS score of 3 or less (conservative treatment recommended) was 6.1 ± 1.3 points. The mean TLICS score with an LSC score of 7 or more (additional anterior reconstruction recommended) was 6.6 ± 2.7 points, and the mean TLICS score with an LSC score of 6 or less (expectation of good clinical results with posterior short fusion) was 5.0 ± 2.5 points. The TLICS score was 3 or less, and the LSC score was 7 or more in 13 patients (13 %). CONCLUSIONS Although the TLICS scores correlated with the LSC scores, a single application of TLICS might not be sufficient to identify those patients who have a TLICS score of 3 or less and an LSC score of 7 or more as surgically indicated. However, an additional LSC evaluation avoided deviations as the two classifications complemented each other, and it was useful in determining the best treatment options for thoracolumbar burst fractures.