Two level & multiple level thoracic disc herniation.
A. Boriani & colleagues reported a two-level thoracic disc herniation. According to the authors only 26 cases of dual disc herniations are reported before 1994. However, this case was a double, contiguous disc herniation in the thoracic spine (T7-T8, T8-T9) in a 44-year-old man. The findings are as follows:
1. Intermittent episodes of weakness and numbness in the lower extremities.
2. Paraesthesias radiating to the anterior and medial surfaces of the thigh and the leg (in this case parasthesia was mostly on the left side).
3. Mild sexual and urinary dysfunction.
B. Chen & colleagues reported a single case of acute noncontiguous multiple-level thoracic disc herniations with myelopathy. According to these authors multiple-level symptomatic disc herniations of the thoracic spine are rare, and the reported cases are mostly of contiguous, two-level lesions with chronic clinical presentation. Prior to 2004 no case of acute three-level noncontiguous ruptured thoracic disc herniations with myelopathy has been reported. This cases reported by them was of a 38-year-old man with a unique acute, triple-level, noncontiguous thoracic disc herniation (T6, T9-T10, and T11-T12). It presented as follows after minor trauma resulting from a motorcycle accident.
1. Delayed onset of lower limb weakness,
2. Paresthesias below the T10 dermatome.
3. Urinary dysfunction
The authors suggested further that thoracic disc herniation is variable and difficult to correlate with imaging findings, decompression at all lesion levels in a patient with symptomatic multiple-level ruptured thoracic disc herniations may be necessary to achieve complete symptom relief and satisfactory results.
Thoracolumbar junction disc herniations:
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. Tokuhashi & colleagues reviewed symptoms of thoracolumbar junction disc herniation to prepare a chart for the level diagnosis in the neurologic findings and symptoms.
Clinical features of 26 patients who later ware operated are as follows:
1. Patients with T10-T11 disc herniation showed moderate lower extremity weakness, increased patellar tendon reflex, and sensory disturbance of the entire lower extremities. (Common symptoms of 2 patients)
2. 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. (Common symptoms of 4 patients)
3. In the T12-L1 disc herniation group, 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. (Common symptoms of 3 patients)
4. 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. (Common symptoms of 6 patients)
5. In the L2-L3 disc herniation group, 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. (Total 11 patients discussed)
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.
Uniqueness of upper lumbar disc herniations:
Albert & colleagues considered L3-4 as a upper lumbar area. They reviewed 141 cases of upper lumbar disc herniations (L1-2, L2-3, L3-4). They found:
1. Pre-interventional signs and symptoms were highly variable.
2. Sensory, motor, and reflex testing was variable and potentially misleading in suggesting a level of herniation.
On analyzing radiographic studies (noncontrast CT, myelography, MRI) individually and operative findings as a standard for comparison, a high false-negative rate was found for all studies when considered individually, especially at the higher L2-3 level.
Uniqueness of upper lumbar spine disc herniations from surgical point:
Sanderson & colleagues considers upper lumbar disc herniations as unique especially from neurosurgical point of view. According to these authors herniated discs at the L1-L2 or L2-L3 level are different entities from those at lower levels of the lumbar spine.
The surgical outcome in terms of postoperative back and radicular pain is worse for herniated discs at L1-L2 and L2-L3 compared with those treated at L3-L4. Patients with L1-L2 or L2-L3 surgically treated herniated discs were more likely to have had previous lumbar surgery and required a fusion more often than their counterparts with L3-L4 herniated discs.
1. Boriani S et al; Spine. 1994 Nov 1;19(21):2461-6.
2. Chen CF et al; Spine. 2004 Apr 15;29(8):E157-60.
3. Tokuhashi Y et al; Spine. 2001 Nov 15;26(22):E512-8.
4. Albert TJ et al; J Spinal Disord. 1993 Aug;6(4):351-9.
5. Sanderson SP et al; Neurosurgery. 2004 Aug;55(2):385-9; discussion 389.