ABSTRACT
BACKGROUND: Lumbosacral transitional vertebra is a commonly seen congenital spinal deformity, and the changes in the muscle innervation pattern and the sensory dermatomes of the lumbosacral nerve roots have been reported, but the changes and its guidance significance for the surgeries of lumbar disc herniation have not been clarified systematically. OBJECTIVE: To explore the possibility of changes in the muscle innervation pattern and the sensory dermatomes of the lumbosacral nerve roots when there is a lumbosacral transitional vertebra. METHODS: The study was in accordance with the ethical requirements of Affiliated Hospital of Binzhou Medical University, and the subjects and their families signed the informed consents. The medical records of 321 patients with single segment lumbar disc herniation who underwent surgical treatment were analyzed retrospectively. Lumbosacral transitional vertebrae were present in 38 of 321 patients (11. 8%). There were 26 cases of sacral lumbarization and 12 cases of lumbar sacralization. Among these 26 patients with sacral lumbarization, 23 had herniated discs at L5/S1 (L6) compressing the S1 (L6) nerve root. Of the 12 patients with lumbar sacralization, 8 had herniated discs at L3/4 compressing the L4 nerve root. In the 283 normally configured patients, 138 had herniated discs at L5/S1 compressing the Si nerve root, 95 had herniated discs at L4/L5 compressing the L5 nerve root, and 47 had herniated discs at L3/L4 compressing the L4 nerve root. The preoperative symptoms of Si nerve root compression in the patients with sacral lumbarization and of L4 nerve root compression in the patients with lumbar sacralization were compared with those of L4, L5 or Si nerve root compression in the patients with normal configuration. RESULTS AND CONCLUSION: (1) The distribution of motor function depression caused by Si nerve root compression was significantly different between sacral lumbarization patients group and normal group (P < 0. 05). (2) The distribution of motor function depression caused by L4 nerve root compression was also significantly different between lumbar sacralization patients group and normal group (P < 0. 05). (3) The motor function depression caused by Si nerve root compression in sacral lumbarization patients was similar to that of the L5 nerve root compression in the normal configuration, while the motor function depression caused by L4 nerve root compression in lumbar sacralization patients was similar to that of the U nerve root compression in the normal configuration. The analysis of the sensory dermatomes also showed similar results. (4) Our results suggest that the function of lumbosacral nerve roots changes in patients with transitional vertebrae. The Si nerve roots in patients with sacral lumbarization tend to serve the usual function of L5 nerve roots (nerve roots move up), and the L4 nerve roots in patients with lumbar sacralization tend to serve the usual function of L5 nerve roots (nerve roots move down).
ABSTRACT
Lumbosacral transitional vertebrae (LSTV) is a common phenomena of developmental anomaly, which is characterized by anatomic variation and biomechanical changes. LSTV is often accompanied with low back pain, lumbar disc herniation, lumbar spinal stenosis, lumbar spondylolisthesis and other spinal diseases. The diagnosis of LSTV has a great significance for proper treatment process. Early imageological studies have limitations on distinguishing different types of LSTV from the aspect of morphological changes. This review focuses on recent studies of LSTV anatomy and variation, its influence in local biomechanics and spinal alignment, and its relationship with spinal diseases.
ABSTRACT
Lumbosacral transitional vertebrae (LSTVs) are a common congenital anomaly of the spine. In the present case, we observed LSTVs in the excessive (sixth lumbar) vertebra. In forensic practice, this anomaly may be useful for personal identification of skeletal remains.