BACKGROUND: One of the characteristics of spinal stenosis is elastin degradation and fibrosis of the extracellular matrix of the ligamentum flavum. However, there have been no investigations to determine which biochemical factors cause these histologic changes. So we performed the current study to investigate the hypothesis that matrix metalloproteinases (MMPs), which possess the ability to cause extracellular matrix remodeling, may play a role as a mediator for this malady in the ligamentum flavum. METHODS: The ligamentum flavum specimens were surgically obtained from thirty patients with spinal stenosis, as well as from 30 control patients with a disc herniation. The extents of ligamentum flavum elastin degradation and fibrosis were graded (grade 0-4) with performing hematoxylin-eosin staining and Masson's trichrome staining, respectively. The localization of MMP-2 (gelatinase), MMP-3 (stromelysin) and MMP-13 (collagenase) within the ligamentum flavum tissue was determined by immunohistochemistry. The expressions of the active forms of MMP-2, MMP-3 and MMP-13 were determined by western blot analysis, and the blots were quantified using an imaging densitometer. The histologic and biochemical results were compared between the two conditions. RESULTS: Elastin degradation and fibrosis of the ligamentum flavum were significantly more severe in the spinal stenosis samples than that in the disc herniation samples (3.14 +/- 0.50 vs. 0.55 +/- 0.60, p < 0.001; 3.10 +/- 0.57 vs. 0.76 +/- 0.52, p < 0.001, respectively). The expressions of the active form of MMPs were identified in all the ligamentum flavums of the spinal stenosis and disc herniation patients. The expressions of active MMP-2 and MMP-13 were significantly higher in the spinal stenosis samples than that in the disc herniation samples (both p < 0.05). The expression of active MMP-3 was slightly higher in the spinal stenosis samples than that in the disc herniation samples, but the difference was not statistically significant (p = 0.131). MMP-2, -3, and -13 were positively stained on the ligamentum flavum fibroblasts. CONCLUSIONS: The current results suggest that the increased expression of active MMPs by the ligamentum flavum fibroblasts might be related to the elastin degradation and fibrosis of the ligamentum flavum in the patients who suffer with lumbar spinal stenosis.
Aged ; Blotting, Western ; Elastin/*metabolism ; Extracellular Matrix/metabolism/pathology ; Female ; Fibrosis ; Humans ; Immunohistochemistry ; Ligamentum Flavum/*metabolism/pathology ; *Lumbar Vertebrae ; Male ; Matrix Metalloproteinase 13/metabolism ; Matrix Metalloproteinase 2/metabolism ; Matrix Metalloproteinase 3/metabolism ; Matrix Metalloproteinases/*metabolism ; Middle Aged ; Spinal Stenosis/*metabolism/pathology

Total and subtotal sternectomy oncological defects can result in large deficits in the chest wall, disrupting the biomechanics of respiration. Reviewing the current literature involving respiratory function and rib motion after sternectomy, autologous rigid reconstruction was determined to provide the optimal reconstructive option. We describe a novel technique for sternal defect reconstruction utilizing a double-barrel, longitudinally oriented, vascularized free fibula flap associated with rib titanium plates fixation. Our reconstructive approach was able to deliver a physiological reconstruction, providing rigid support and protection while allowing articulation with adjacent ribs and preservation of chest wall mechanics.

Total and subtotal sternectomy oncological defects can result in large deficits in the chest wall, disrupting the biomechanics of respiration. Reviewing the current literature involving respiratory function and rib motion after sternectomy, autologous rigid reconstruction was determined to provide the optimal reconstructive option. We describe a novel technique for sternal defect reconstruction utilizing a double-barrel, longitudinally oriented, vascularized free fibula flap associated with rib titanium plates fixation. Our reconstructive approach was able to deliver a physiological reconstruction, providing rigid support and protection while allowing articulation with adjacent ribs and preservation of chest wall mechanics.

Methods: We used 1.0-mm interval computed tomographic scan images of 100 patients (50 men and 50 women) and screw trajectory simulation software. The diameter of all screws was set at 3.5 mm, considering its common usage in real surgery. The anatomical feasibility of placing both pedicle and laminar screws on the same side was evaluated. For all feasible sides, the three-dimensional distance between the screw entry points was measured. Results: In 85% of cases, both pedicle and laminar screws could be placed on both sides, allowing for the insertion of 4 screws. In 11% of cases, 2 screws could be placed on one side, while only 1 screw was feasible on the other side, resulting in the placement of 3 screws. In all 181 sides where both types of screws could be inserted, the distance between their entry points exceeded 16.1 mm, which was sufficient to prevent the collision between the screw heads. Conclusions C2 vertebra can accommodate three (11%) or four (85%) screws in 96% of cases.

STUDY DESIGN: Retrospective radiographic study. OBJECTIVES: To evaluate the characteristics of concurrent degenerative cervical and lumbar spondylolisthesis. SUMMARY OF LITERATURE REVIEW: Concurrent degenerative cervical and lumbar spondylotic diseases have been reported. Given that severe spondylosis can result in spondylolisthesis, one might expect that concurrent spondylolisthesis of the cervical and lumbar spines might also be prevalent. However, the incidence of spondylolistheses in the lumbar and cervical spines might differ due to anatomical differences between the 2 areas. Nonetheless, there is minimal information in the literature concerning the incidence of concurrent cervical and lumbar spondylolisthesis. MATERIAL AND METHODS: We evaluated standing cervical and lumbar lateral radiographs of 2510 patients with spondylosis. Concurrence, age group, gender, and direction of spondylolisthesis were evaluated. Lumbar spondylolisthesis was defined as at least Meyerding grade I and degenerative cervical spondylolisthesis was defined as over 2 mm of displacement on standing lateral radiographs. RESULTS: Lumbar spondylolisthesis was found in 125 patients (5.0%) and cervical spondylolisthesis was found in 193 patients (7.7%). Seventeen patients had both degenerative cervical and lumbar spondylolistheses (0.7%). Lumbar spondylolisthesis is a risk factor for co-existing cervical spondylolisthesis. Lumbar spondylolisthesis was more common in females than males, independent of advancing age. In contrast, degenerative cervical spondylolisthesis was more common in older patients, independent of gender. Anterolisthesis was more common in the lumbar spine. Retrolisthesis was more common in the cervical spine. CONCLUSIONS: There was a higher prevalence of degenerative cervical spondylolisthesis in patients with degenerative lumbar spondylolisthesis.
Cervical Vertebrae ; Female ; Humans ; Incidence ; Lumbar Vertebrae ; Male ; Prevalence ; Retrospective Studies ; Risk Factors ; Spine ; Spondylolisthesis ; Spondylosis

OBJECTIVES: To evaluate the characteristics of concurrent degenerative cervical and lumbar spondylolisthesis.SUMMARY OF LITERATURE REVIEW: Concurrent degenerative cervical and lumbar spondylotic diseases have been reported. Given that severe spondylosis can result in spondylolisthesis, one might expect that concurrent spondylolisthesis of the cervical and lumbar spines might also be prevalent. However, the incidence of spondylolistheses in the lumbar and cervical spines might differ due to anatomical differences between the 2 areas. Nonetheless, there is minimal information in the literature concerning the incidence of concurrent cervical and lumbar spondylolisthesis.MATERIAL AND METHODS: We evaluated standing cervical and lumbar lateral radiographs of 2510 patients with spondylosis. Concurrence, age group, gender, and direction of spondylolisthesis were evaluated. Lumbar spondylolisthesis was defined as at least Meyerding grade I and degenerative cervical spondylolisthesis was defined as over 2 mm of displacement on standing lateral radiographs. RESULTS: Lumbar spondylolisthesis was found in 125 patients (5.0%) and cervical spondylolisthesis was found in 193 patients (7.7%). Seventeen patients had both degenerative cervical and lumbar spondylolistheses (0.7%). Lumbar spondylolisthesis is a risk factor for co-existing cervical spondylolisthesis. Lumbar spondylolisthesis was more common in females than males, independent of advancing age. In contrast, degenerative cervical spondylolisthesis was more common in older patients, independent of gender. Anterolisthesis was more common in the lumbar spine. Retrolisthesis was more common in the cervical spine. CONCLUSIONS There was a higher prevalence of degenerative cervical spondylolisthesis in patients with degenerative lumbar spondylolisthesis.