Radiological Parameters of Undegenerated Cervical Vertebral Segments in a Korean Population

BACKGROUND: Several scoring systems for cervical disc and facet joint degeneration, using radiography or computed tomography, have been developed and tested for reliability. However, definitions of disc height and facet joint space narrowing vary. To our knowledge, no study has reported quantitative data for normal radiologic values of the cervical spine in the Korean population. The purpose of this study is to determine normal cervical disc height, disc height ratio, and facet joint space values, and investigate the correlation between demographic data and these values. METHODS: We performed a retrospective study of patients who underwent artificial disc replacement of the cervical spine. Disc heights and facet joint spaces were measured using cervical neutral lateral radiographs and computed tomography. The means, standard deviations, and 95% confidence intervals of the values were determined. RESULTS: We measured 148 intervertebral discs and 352 posterior facet joints. The mean disc height measured by plain radiography and computed tomography was 5.57 ± 0.81 mm and 4.94 ± 0.94 mm, respectively. The mean facet joint space values measured by plain radiography and computed tomography were 1.94 ± 0.45 mm and 1.43 ± 0.39 mm, respectively. The disc heights and facet joint space values measured by plain radiography were greater than those measured by computed tomography. The lower limit of the 95% confidence interval of the disc height ratio calculated by plain radiography and computed tomography was greater than 0.94 at all levels except for C5–6. Patient height and disc height showed a tendency of positive correlation. CONCLUSIONS: In a Korean population, the normal cervical disc height was about 5.0 mm and the normal facet joint space was 1.4 mm. Disc height ratio can reliably identify normal cervical disc height in patients with mild degeneration. Patient height was positively correlated with disc height and facet joint space. Thus, when selecting a cervical implant, surgeons should consider patient height as well as estimated normal disc height.

Clinical Results of Femoral Subtrochanteric Fractures

PURPOSE: This study examined the clinical course of subtrochanteric fractures of the femur as well as the risk factors of complications. MATERIALS AND METHODS: A retrospective study was performed on 56 patients with femoral subtrochanteric fractures who were treated at our hospital from 2004 to 2008. Risk factors, such as the type of fracture, type of implant, soft tissue dissection at the fracture site, communition of the medial cortex and degree of fracture displacement after the reduction, were compared to determine their effect on the rate of complications, such as nonunion and implant failure. Open reduction with a soft tissue dissection at the fracture site was performed in 34 cases, and a closed reduction was performed in 22 cases. Thirty five cases had medial cortex communition and 21 cases did not. RESULTS: There were 8 cases of nonunion(14.3%). There was a positive correlation between the degree of fracture displacement after the reduction and the union time (P=0.017). The union time was longer when there was communition of the medial cortex. A subtrochanteric fracture using an open reduction tended to have a long union time but this was not statistically significant. There was no correlation between the type of implant and union time. CONCLUSION: The union time is longer in subtrochanteric fractures with communition of the medial cortex. Therefore, it is important to preserve the blood supply at the fracture site using a closed reduction and restore the fracture reduction accurately.

Oxidative Stress Induced--Expression Changes of Zonular Occludens--1 in Tight Junction / 체질인류학회지

The homeostasis of microenvironment in central nervous system, essential for normal function, is maintained by blood-brain barrier (BBB). ZO-1 in tight junctions (TJs) plays an important role in maintaining BBB endothelial ion and solute barriers. Malfunction of BBB by reactive oxygen species has been attributed to disruption of TJs. This study examined H2 O2 effects on paracellular permeability and changes in TJ protein ZO-1 using primary culture of bovine brain microvessel endothelial cells. The BBB permeability,measured as TER, increased in a dose-and time-dependent manner when treated with H2O2 (0.01, 0.1, 1.0 mM). Cytotoxicity test revealed that H2O2 did not cause cell death below 1 mM H2 O2 within 4 hr. H2O2 caused intermittent disruption and loss of ZO-1 at tight junctions, but ZO-1 maintained steady state levels of expression. In conclusion, we report that H2O2 induces increased paracellular permeability of BBB that is accompanied with alterations in localization of ZO-1.