The proteasome inhibitor bortezomib inhibits intimal hyperplasia of autologous vein grafting in rat model.

OBJECTIVE: Increasing evidence indicates that inflammation plays an important role in intimal hyperplasia (IH) induced by autologous vein grafts. The proteasome inhibitor bortezomib shows anti-inflammatory effects, so we used an autologous vein transplantation model to test whether bortezomib inhibits neointimal formation in transplant-induced vasculopathy. MATERIALS AND METHODS: We subjected 88 rats to autologous external jugular vein grafting surgery randomly assigned to be treated with bortezomib or vehicle. After 24 or 72 hours, rats were humanely killed and vein grafts processed for real-time RT-PCR (24 and 72 hours), ELISA (24 hours), or neutrophil chemotaxis assay (24 hours). Subsequently, rats were humanely killed at 1 and 2 weeks after grafting with samples processed for morphometric analysis. RESULTS: Bortezomib significantly inhibited IH at 2 weeks compared with untreated controls (P < .05). Expression of mRNA for vascular cell adhesion molecule-1, intercellular adhesion molecule-1, cytokine-induced neutrophil chemoattractant 2beta, monocyte chemoattractant-1, interleukin (IL)-1, IL-6, and tumor necrosis factor-alpha markedly increased in injured vessels during the first day after surgery declining over the following 3 days. Bortezomib significantly attenuated gene expression and protein levels of most inflammatory mediators (P < .05), simultaneously inhibiting neutrophil chemotactic activity of vessel homogenates. CONCLUSIONS: Bortezomib inhibited neointimal formation at least partially by attenuating the inflammatory response in transplant-induced vasculopathy. It may become a novel vasoprotective agent in the clinical field.

The value of bilateral ipsilateral and contralateral motor evoked potential monitoring in scoliosis surgery.

Intraoperative monitoring (IOM) of the motor pathways is a routine procedure for ensuring integrity of corticospinal tracts during scoliosis surgery. We have previously demonstrated presence of ipsilateral motor evoked potentials (MEPs) during IOM for scoliosis surgery, but its significance was uncertain. In this case series, we show concurrent ipsilateral and contralateral MEP amplitude changes obtained with cortical stimulation are of value in reducing false positive observations during IOM. The use of this easily recordable MEP is thus advocated as a diagnostic adjunct to contralateral MEPs for scoliosis and spinal surgery.

Motor and somatosensory abnormalities are significant etiological factors for adolescent idiopathic scoliosis.

OBJECTIVE: In adolescent idiopathic scoliosis (AIS), we explore the role of lateralized motor and somatosensory abnormalities as a possible etiological factor. METHODS: Intraoperative transcranial electrical stimulation was performed in 15 AIS and 14 adult degenerative scoliosis (ADS) patients. Inter-side motor output balance (MOB) by comparing the ratios of right to left motor evoked potentials (MEP) amplitudes, and inter-side motor output excitability (MOE) computed with MEP amplitude, was determined separately for both patients groups. For somatosensory evoked potentials (SSEP), peak to peak P37 amplitudes from right and left lower limb SSEP and inter-side P37 amplitude ratios were obtained. RESULTS: Inter-side MOB was significantly asymmetric in AIS patients, contributed mainly by inter-side MOB changes in the upper than the lower limbs. Inter-side MOE comparisons of ipsilateral and contralateral MEP amplitudes were significantly different between AIS and ADS patients. Mean upper limb MEP amplitudes were significantly reduced in AIS patients. Amplitude of the right upper limb MEPs were positively correlated with inter-side MEP ratio. AIS patients show larger mean MEP amplitudes on the same side as the scoliotic curve. Overall, no correlation of Cobb's angle or total levels of scoliosis involvement with inter-side MOB and MOE parameters was found. Inter-side SSEP ratios were significantly higher in AIS patients. CONCLUSIONS: Primary dysfunctional and distributed motor output contributing to abnormalities of inter-side MOB and MOE changes involving the upper limbs is evident in AIS. Simultaneous but independent somatosensory and motor observations seen these patients suggest a central mechanism as an etiological factor.

The Torg--Pavlov ratio in cervical spondylotic myelopathy: a comparative study between patients with cervical spondylotic myelopathy and a nonspondylotic, nonmyelopathic population.

STUDY DESIGN: A radiologic study to compare the Torg--Pavlov ratios between patients with cervical spondylotic myelopathy and a nonspondylotic, nonmyelopathic population. OBJECTIVES: To determine and compare the Torg--Pavlov ratios between the two groups of patients. SUMMARY OF BACKGROUND DATA: Patients with congenital cervical spinal canal stenosis are more likely to develop cervical spondylotic myelopathy. The Torg--Pavlov ratio eliminates errors related to magnification, a problem with determination of spinal canal stenosis from direct measurements of plain cervical spine radiographs. There has only been one other study that directly compares the Torg--Pavlov ratio between patients with cervical spondylotic myelopathy and a normal control population. METHODS: The preoperative plain lateral cervical spine radiographs of 28 patients with cervical spondylotic myelopathy requiring surgical decompression were compared with radiographs of 88 nonspondylotic, nonmyelopathic patients. The Torg--Pavlov ratio was computed for each level from C3 to C7. RESULTS: The study showed that the Torg--Pavlov ratio is significantly smaller (P < 0.001) in myelopathic patients (mean 0.72 +/- 0.08) compared with the control patients (mean 0.95 +/- 0.14). This was so when individual levels and the mean values were compared. Age was also found to be a significant factor (P = 0.002), although lesser in magnitude when compared with the Torg--Pavlov ratio (P = 0.0001). CONCLUSIONS: The Torg--Pavlov ratio is significantly lower in patients with cervical spondylotic myelopathy compared with a nonspondylotic, nonmyelopathic population. It could possibly be used to predict the likelihood of developing cervical spondylotic myelopathy.

Patellar allografts in anterior cervical fusion - a two-year clinical and radiographic study.

Donor site morbidity, which occurs in 15% to 20% with the use of autografts for anterior cervical fusion, is eliminated with the use of allografts. While allografts from the iliac crest, ribs, fibula, femoral head and skull have been used in anterior cervical fusion, the use of patellar allografts has not been previously reported. Twenty-two patients underwent Cloward anterior cervical decompression and fusion using bicortical patellar allografts from 1993 to 1997. Fifteen patients, with a follow-up period of at least two years, were reviewed. Eleven patients (73.4%) had good or excellent results at an average of 42.8 months after surgery. Fourteen patients (93.4%) achieved union. Two patients (13.3%) developed collapse of the graft with extrusion, one of whom still achieved union. These results are comparable to those reported of anterior cervical fusion using autografts or other types of allografts.

Results of cervical laminoplasty and a comparison between single and double trap-door techniques.

Thirty-seven patients were studied for an average of 32.1 months after canal-expansive laminoplasty for the treatment of multiple-level cervical stenosis caused by spondylosis, ossification of posterior longitudinal ligament, prolapsed intervertebral disc, and other conditions. Short-term and medium-term results were recorded clinically, using the scoring system proposed by the Japanese Orthopedic Association. The canal expansion was also recorded with radiological studies. The improvement rate was good to excellent in 58.3% of the patients. Postoperative neurological deterioration occurred in only four patients. Poorer results were observed in female patients and in those in whom surgery was delayed. Surgery within 12 months of onset of symptoms gave good results. Serious complications occurred in only two patients. There were 12 patients who were treated with the single trap-door (unilateral) laminoplasty and 25 patients treated with the double trap-door (sagittal splitting of the spinous processes) laminoplasty; their results were compared. There was no significant difference in neurological outcome between the two methods.