Symptoms of thoracolumbar junction disc herniation.

STUDY
DESIGN: A retrospective clinical review of patients with thoracolumbar junction disc herniation.
OBJECTIVES: To evaluate the clinical features of thoracolumbar junction disc herniation and to prepare a chart for the level diagnosis in the neurologic findings and symptoms. SUMMARY OF BACKGROUND DATA: Thoracolumbar junction disc herniations show a variety of signs and symptoms because of the complexity of the upper and lower neurons of the spinal cord, cauda equina, and nerve roots. Furthermore, much is still unknown about thoracolumbar junction disc herniations because of their rare frequency.
METHODS: The clinical features of 26 patients who had undergone operations for single disc herniations at T10-T11 through L2-L3 were investigated. Affected levels were as follows: 2 patients with disc herniation at T10-T11 disc, 4 patients at T11-T12, 3 patients at T12-L1, 6 patients at L1-L2, and 11 patients at L2-L3. The level of disc space of interest was confirmed with whole-spine plain roentgenograms. The caudal end of the cord was judged by magnetic resonance imaging and computed tomographic myelogram.
RESULTS: Two patients with T10-T11 disc herniation showed moderate lower extremity weakness, increased patellar tendon reflex, and sensory disturbance of the entire lower extremities. Three of four patients with T11-T12 disc herniation experienced lower extremity weakness, and three patients had accentuated patellar tendon reflex. Sensory disturbance was observed in the anterolateral aspect of the thigh in one patient and on the entire leg in three patients. Bowel and bladder dysfunction was noted in three patients. In the T12-L1 disc herniation group (n = 3), muscle weakness and atrophy below the leg were advanced, and bowel and bladder dysfunction were also noted. Two of these three patients had bilateral drop foot, and one patient had unilateral drop foot; sensory disturbance was noted in the sole or foot and around the circumference of the anus, and the patellar tendon reflex and Achilles tendon reflex were absent. All six patients with L1-L2 disc herniation showed severe thigh pain and sensory disturbance at the anterior aspect or lateral aspect of the thigh. On the other hand, there were no clear signs of lower extremity weakness, muscle atrophy, deep tendon reflex, or bowel and bladder dysfunction in these patients. In the L2-L3 disc herniation group (n = 11), all patients had severe thigh pain and sensory disturbance of the anterior aspect or the lateral aspect of the thigh. Weakness in the quadriceps was noted in five patients and weakness in the tibialis anterior in two patients. Decreased or absence of patellar tendon reflex was observed in nine patients. Five patients had positive straight leg raising test results, and eight patients showed positive femoral nerve stretch test results.
CONCLUSION: Among thoracolumbar junction disc herniations, T10-T11 and T11-T12 disc herniations were considered upper neuron disorders, T12-L1 disc herniations were considered lower neuron disorders, L1-L2 disc herniations were considered mild disorders of the cauda equina and radiculopathy, and L2-L3 disc herniations were considered radiculopathy. These findings had relatively distinct differences among herniated disc levels.