BACKGROUNDScheuermann's disease (SD) is a spinal disorder and includes both a classic form and an atypical form. Interestingly, its existence among the general population as well as the disc disease patients is common. One of our previous studies showed that about 18% of the hospital staff members meet the SD criteria. On the other hand, another study has demonstrated that 95.2% of the symptomatic thoracolumbar disc herniation (STLDH) patients meet the SD criteria, which suggests that STLDH is very likely a special form of SD. The purpose of this study was to discriminate the factors contributing to the development of STLDH by comparing STLDH patients with the healthy SD-like hospital staff members.

METHODSThis is a retrospective study including 33 STLDH patients who met the SD criteria and 30 SD-like hospital staff members. The STLDH group was chosen from a group of patients who underwent surgery after a diagnosis of STLDH (T10/11-L1/2) at our hospital between June 2007 and June 2010. SD-like hospital staff members were chosen from a database created in 2007, which contained a lumbar MR and low back pain (LBP) questionnaire of 188 hospital staff members. The demographic and radiologic characteristics were compared between groups.

RESULTSThere was no statistical difference in sex, age, and height between the two groups. The STLDH patients had higher body weight, boby mass index, and thoracolumbar kyphotic angle than SD-like hospital staff members. In addition, STLDH patients had more levels of Schmorl's nodes (3.5±1.7 vs. 2.0±1.9, t = 3.364, P = 0.001) and irregular endplateson (4.0±1.9 vs. 2.7±1.9, t = 2.667, P = 0.010) compared to the SD-like hospital staff members.

CONCLUSIONSHigher body weight, higher body mass index, larger thoracolumbar kyphosis, and more Schmorl's nodes and irregular endplates on MR may be associated with the development of STLDH in "SD-like people."