Imaging study of paravertebral muscle degeneration in degenerative lumbar instability / 中华外科杂志

<p><b>OBJECTIVES</b>To compare the paravertebral muscle (such as multifidus, erector spinae, psoas muscle) changes between the patients with degenerative lumbar instability and normal person by MRI and to observe the degeneration of paravertebral muscles. To analyze the relationship between paravertebral muscle degeneration and lumbar curvature of degenerative lumbar instability.</p><p><b>METHODS</b>Sixty patients with degenerative lumbar instability were retrospectively enrolled from December 2011 to July 2013 as degeneration group, meanwhile 60 health persons with no degenerative lumbar instability were selected as control group. No significant differences were found in the gender, age and body mass index between the two groups. The cross-sectional area(CSA) and percentage of fat infiltration area (FIA) of the paravertebral muscles at the L4-S1 levels were measured using T2-weighted axial MRI and Image J soft ware. And the lumbar curvature(expressed as lumbar lordosis angle) of all the patients in lumbar X-ray were measured in the two groups. The measured data were analyzed with independent samples t-test.</p><p><b>RESULTS</b>The difference of multifidus cross-sectional area and the percentage of fat infiltration in the patients of degenerative lumbar instability at the L4-L5, L5-S1 level, compared with the control group, was statistically significant (t = 2.768, t = 6.216, P < 0.05). Between the two groups, the percentage of fatty infiltration in erector spinae showed significant differences (t = 5.862, P < 0.05). The cross-sectional area of erector spinae and the degeneration of the psoas muscle between the two groups was not statistically significant. The lumbar lordsis angle in the patients with degenerative lumbar instability was (43.9 ± 15.6)°, which was higher than the (39.3 ± 14.2)° in control group (t = 2.915, P < 0.05).</p><p><b>CONCLUSIONS</b>Compared with the control group, patients with degenerative lumbar instability exists erector spinae and multifidus muscle degeneration, and erector spinae is more obvious. The degeneration among psoas muscle, erector spinae and multifidus muscle are inconsistent, which may be related to the increasing of the lumbar lordosis angle in the patients with degenerative lumbar instability.</p>

Pedicle subtraction osteotomy with trephine for old thoracolumbar compression fracture with kyphotic deformity / 中华骨科杂志

Objective To explore value of trephine in pedicle subtraction osteotomy (PSO) for old thoracolumbar compression fracture with kyphotic deformity.Methods Thirty seven patients who underwent surgical treatment for old thoracolumbar kyphotic deformity in our hospital from February 2005 to February 2010 were retrospectively reviewed.Among them,21 patients underwent conventional PSO and 16 patients underwent PSO with trephine.In conventional PSO group,there were 14 males and 7 females,the average age was 55.6±3.7 years and the mean Cobb angle was 45.3°±4.6°.In PSO with trephine group,there were 11 males and 5 females,the average age was 53.3±4.2 years and the mean Cobb angle was 47.6°±5.9°.Results All patients were successfully followed up.The duration of follow-up ranged from 12 to 22 months in conventional PSO group,while 13 to 20 months in PSO with trephine group.The operation time,blood loss,amount of blood transfusion were 224±45 min,1043±234 ml,876±300 ml respectively in conventional PSO group,while 180±31 min,785±163 ml,500±230 ml in PSO with trephine group.Immediately after operation,correction rate of Cobb angle was 91.4％ in conventional PSO group and 90.9％ in PSO with trephine group.At final follow-up,the correction of Cobb angle lost 5.8％ in conventional PSO group and 6.2％ in PSO with trephine group.The improvement rate of JOA score was 81.1％ in conventional PSO group and 83.7％ in PSO with trephine group.The VAS score decreased 7.7±1.1 in conventional PSO group and 7.8±0.8 in PSO with trephine group.One patient in conventional PSO group experienced saddle numbness immediately after operation,which alleviated at final follow up.All patients achieved bony fusion at final follow up.No infection,screw loosening or breakage occurred in both groups.Conclusion The use of trephine in PSO for old thoracolumbar compression fracture with kyphotic deformity can reduce operation time,blood loss and improve efficiency of osteotomy.