The relationship between central motor conduction time and spinal cord compression in patients with cervical spondylotic myelopathy.

STUDY DESIGN: Retrospective study. OBJECTIVES: Few studies have reported a relationship between central motor conduction time (CMCT), which evaluates corticospinal function, and degree of spinal cord compression in patients with myelopathy. Thus, there is no consensus on predicting the degree of prolonged CMCT on the basis of the degree of spinal cord compression. If a correlation exists between CMCT and spinal cord compression, then spinal cord compression may be a useful noninvasive clinical indicator of corticospinal function. Therefore, this study evaluated the relationship between CMCT and cervical spinal cord compression measured by magnetic resonance imaging (MRI) in patients with cervical spondylotic myelopathy (CSM). SETTING: Hiroshima University Hospital in Japan. METHODS: We studied 33 patients undergoing laminoplasty. Patients exhibited significant cervical spinal cord compression on both MRI and intraoperative electrophysiological examination. We assessed transcranial magnetic stimulation measurement of CMCT; spinal cord compression parameters such as area, lateral diameter, anteroposterior diameter and flattening of the spinal cord at the lesion site and C2/3 levels on MRI; and pre- versus postoperative Japanese Orthopaedic Association (JOA) scores. RESULTS: Correlations between CMCT and flattening as well as anteroposterior diameter of the spinal cord at the lesion level were observed. Strong correlations between CMCT and the ratio of the flattening and anteroposterior diameter parameters at the lesion level to that at the C2/3 level were also observed. CONCLUSIONS: Measurement of spinal cord compression may be useful for the evaluation of corticospinal function as a proxy for CMCT in patients with CSM.

Resection of spinous processes can cause spinal cord injury in patient with ossification of the posterior longitudinal ligament in the thoracic spine.

STUDY DESIGN: Case report. OBJECTIVE: To report intraoperative spinal cord injury by resection of spinous processes in a 73-year-old man with ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine. METHODS: A 73-year-old man presented with cervicothoracic OPLL with bilateral numbness and clumsiness of his hand, weakness of his lower extremities and severe gait disturbance. His Japanese Orthopaedic Association (JOA) score was 7.5 out of 17. Cervical laminoplasty (C2-6), cervicothoracic laminectomy (C7-T10) and posterior fusion (C7-T10) were performed in the prone position with electrophysiologic monitoring of the spinal cord-evoked potentials (SCEPs). RESULTS: The spinal processes with supra- and interspinous ligaments between C7 and T10 were resected. After resection, the amplitude of SCEP waveforms decreased rapidly to <10% of control levels. Laminectomy was performed, and, after 80 min of SCEP deterioration, an instrumented fusion with correction for kyphosis was completed. The SCEP amplitude recovered gradually. Immediately after surgery, the patient suffered severe motor loss in both lower limbs. His neurological recovery progressed gradually from 2 days after surgery, and he was able to walk at 3 months after surgery. At 6 years after surgery, the JOA score was 11. CONCLUSION: Our results suggest that intraoperative spinal cord injury can occur before posterior decompression by resection of spinal processes with supra- and interspinous ligaments. The timing of the instrumented stabilization using a temporary rod is important and should be considered immediately after posterior exposure of the spine.

Induction of angiogenesis by hyperplastic colonic mucosa adjacent to colon cancer.

We determined whether hyperplastic mucosa adjacent to colon cancer contributes to neoplastic angiogenesis. Surgical specimens of human colon cancer (40 Dukes' stage B and 34 Dukes' stage C) were analyzed by immunohistochemistry for expression of proliferative and angiogenic molecules. The mucosa adjacent to Dukes' stage C tumors (but not Dukes' stage B tumors) had a higher Ki-67 labeling index and a higher expression of epidermal growth factor receptor and transforming growth factor-alpha than distant mucosa. The expression levels of vascular endothelial growth factor, basic fibroblast growth factor, interleukin-8, and the vascular density in the adjacent mucosa were similar to those in the tumor lesions and significantly higher than those in the distant mucosa. The expression of interferon-beta inversely correlated with the level of pro-angiogenic molecules and the vascular density. The injection of metastatic human colon cancer cells and murine colon cancer cells into the cecal wall of mice induced hyperplastic changes in the adjacent mucosa which expressed higher levels of epidermal growth factor receptor, basic fibroblast growth factor, and vascular endothelial growth factor, and lower levels of interferon-beta than did the control mucosa, which directly correlated with the degree of hyperplasia. These data suggest that metastatic human colon cancer cells can induce hyperplasia in the adjacent mucosa, which in turn produces angiogenic molecules that contribute to neoplastic angiogenesis.