Delayed decompression for cauda equina syndrome secondary to lumbar disc herniation: long-term follow-up results / 南方医科大学学报

<p><b>OBJECTIVE</b>To assess the impact of delayed decompression on long-term neurological and bladder function recovery in patients with cauda equina syndrome (CES) secondary to lumbar disc herniation (LDH).</p><p><b>METHODS</b>The clinical data of 35 patients receiving delayed decompression surgery for CES secondary to LDH were reviewed. The bladder empty function, bowel control, sexual ability and neurological functions of the lower limbs were evaluated after the operation, and the urodynamic changes were assessed in 6 patients with urodynamic data before and after the operation.</p><p><b>RESULTS</b>Surgical decompression was performed at 4.1∓3.9 weeks in 12 patients with complete CES and at 5.5∓7.6 weeks in 23 patients with incomplete CES after the onset of symptoms. The patients were followed up for a mean of 43.0∓28.9 months (3-110 months). In the 23 patients with incomplete CES, 19 obtained full recovery, 4 had slight sensory alterations in the saddle area or the lower limbs. In the 12 patients with complete CES, 2 had full recovery, 4 reported slight sensory alterations in the saddle area or the lower limbs (including 2 with occasional constipation); 6 still had sense deficit in the saddle area and difficulties in bladder or bowl emptying, but they all reported significant improvements compared to the condition before operation. Urodynamic analysis in the 6 patients with pre- and postoperative urodynamic data showed increased abdominal pressure when voiding with significantly reduced residual urine in all the 6 patients; 4 patients with abnormal first desire volume before operation reported recovery after the operation.</p><p><b>CONCLUSION</b>Patients with LDH-induced CES who missed the chance of early decompression can still expect favorable functional recovery in the long term. The improvement of bladder function following decompression is probably a result of recovery of bladder sensation and the compensation by increased intra-abdominal pressure. The key strategy to promote bladder function recovery in these patients is to promote the detrusor recovery.</p>

Effects on facet joint force and stability of lumbar spine following asymmetric lumbar discectomy / 医用生物力学

Objective To investigate the effect of asymmetric lumbar discectomy on facet joint force and stability of lumbar spine. Methods Seven human cadaver specimens (L2-3 segment) were selected to make intact, 1/4 discectomy and 1/2 discectomy status and applied with pure moment of 7.5 N•m. The range of motion (ROM) and facet joint force of L2-3 segment during flexion/extension, lateral bending and axial rotation were recorded, respectively. Results During extension, a significant increase in facet joint force was found under 1/4 discectomy status at the remained side. During lateral bending, the facet joint force at both sides under 1/2 discectomy status increased significantly than that under intact status. During axial rotation, facet joint force increased significantly only at the side without discectomy under 1/2 discectomy status. Except flexion, ROM under 1/4 discectomy and 1/2 discectomy status were larger than that under intact status in all the other motion directions (P<0.05). There was no significant difference in ROM between both sides during lateral bending and axial rotation direction. Conclusions The asymmetric lumbar discectomy can increase the ROM in all motion directions except flexion, and can enlarge the facet joint force asymmetrically, which indicate that instability of lumbar spine and facet joint force increasing resulted from asymmetric degeneration of the disc might lead to backache.

Establishment of a rabbit model of scoliosis induced by asymmetric load using springs / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish rabbit model of scoliosis induced with stable asymmetric lumbar loads.</p><p><b>METHODS</b>Scoliosis was induced in 10 two-month-old New Zealand rabbits using 316L stainless steel springs placed between the unilateral transverse processes of L2 and L5. Serial radiographs were documented before and at 1, 4, 8, 9 and 12 weeks after the operation. At weeks, the rabbits were randomly divided into SR group (n=5) with the spring removed and SK group (n=5) without spring removal.</p><p><b>RESULTS</b>All the rabbits survived the experiment with Cobb angle all greater than 10 degree at the end of the experiment. Significant changes were found in the Cobb angles and kyphotic angles at 1, 4 and 8 weeks after the operation (P<0.05). At 8 weeks, the Cobb angle, the kyphotic angle and the length of the spring were similar between SR and SK groups (P>0.05), and in the 4 weeks following spring removal in SR group, the Cobb angle and the kyphosis decreased significantly compared with those in SK group (P<0.05). Micro-CT showed that the BV/TV of the concave side was greater than that of the convex side. The length of the spring did not show obvious changes during the experiment (P>0.05).</p><p><b>CONCLUSIONS</b>Asymmetric lumbar loading is a convenient, time-saving, and highly reproducible approach for establishing rabbit models of scoliosis.</p>

Perioperative complications of single-stage surgical management for spinal tuberculosis / 中华外科杂志

<p><b>OBJECTIVE</b>To analyze the causes of perioperative complications of single-stage surgical management for spinal tuberculosis.</p><p><b>METHODS</b>One hundred and twenty patients with thoracic, lumbar and lumbosacral spinal tuberculosis were treated by single-stage surgical management from January 1997 to January 2006 in our unit, including seventy-five males and forty-five females. The mean age was 34.5 (range 17 to 68) years old. The lesion ranged from T(6) to S(1). The anterior procedures of anterior debridement, interbody fusion and anterior fixation were carried out in sixty-five cases, posterior procedures in twenty-six cases, and combined anterior and posterior procedures in twenty-nine cases, respectively. The complications that occurred during surgical procedure and 1 month after operation were recorded. Underlying causes were analysed.</p><p><b>RESULTS</b>There were 10 cases (8.3%) were recorded of mild to severe complications during perioperative period in 120 patients. The complications and underlying causes were as follows: (1) A patient died from liver failure and blood coagulation dysfunction after operation due to inappropriate surgical timing (n = 1), in which case the patient with lumbosacral spinal tuberculosis also suffered from alcoholic liver sclerosis and dysfunction. (2) False diabetes insipidus (n = 1) and deep vein thrombosis of lower limbs (n = 1) occurred as result of surgical trauma. (3) Tear of iliac vein (n = 1) occurred with lumbosacral spinal tuberculosis because of unclear anatomical relationships when anterior debridement was performed. Injury of lumbar nerve roots (n = 3) and hemothorax (n = 1) also occurred due to mispractice of surgical procedures. (4) Paralysis intestinal obstruction and hypokalemia (n = 2) occurred after anterior procedures for lumbar spinal tuberculosis as a result of other reasons.</p><p><b>CONCLUSIONS</b>Improper perioperative care will lead to complications of single-stage surgical procedures for spinal tuberculosis. Emphasis should be put on preoperative evaluation, surgical planning, and postoperative caring for prevention of complications.</p>

Analysis of the long-term outcome of anterior approach surgery on cervical spondylotic myelopathy / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the long-term efficacy of anterior approach surgery on cervical spondylotic myelopathy and factors affecting prognosis.</p><p><b>METHODS</b>The data in 116 patients suffered from cervical spondylosis from January 1992 to December 2000 were reviewed, including 80 male cases and 36 female cases, whose age ranged from 36 to 76 years (mean, 51 years). The preoperative course of disease was 2 months to 20 years (mean, 19 months). There were 65 cases (56.0%) with single segments involved, 44 cases (37.9%) with two segments, 7 cases (6.0%) with three segments. Ninety-eight cases were onset slowly, 18 cases with no remote cause and aggravating quickly. Three kinds of surgeries were performed: anterior cervical decompression and autoiliac bone interbody fusion, anterior cervical decompression and fusion with threaded fusion cage, anterior cervical decompression and autoiliac bone interbody fusion with anterior screw-plate system. Improvement in spinal cord function was assessed using the Japanese Orthopaedic Association (JOA) scoring system, the long-term efficacy and influential factors were also analyzed.</p><p><b>RESULTS</b>The mean follow-up time was 7 years and three months (5 - 12 years). The mean preoperative JOA score was 9.34 +/- 1.81. The mean postoperative JOA score was 10.35 +/- 1.85. At the final follow-up, the JOA score was 14.09 +/- 1.90 and the recovery rate was 63.2%. Among the total patients, 27 cases were excellent, 47 cases were fine, 23 cases were good, 19 cases were poor, the fineness rate was 63.8%. The long-term efficacy of anterior approach surgery has close correlations with time of course, age of onset, preoperative spinal cord function and the number of affected segments, but has no correlations with modes of fusion and internal fixation.</p><p><b>CONCLUSIONS</b>The patients will be attentively observed while having a definite diagnosis of cervical spondylotic myelopathy. The good long-term results will be obtained after early anterior cervical decompression and fusion.</p>

The selection of the surgical approach in the management of fracture and dislocation of lower cervical spine combined spinal cord injury / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate how to select an appropriate surgical approach in the management of fracture and dislocation of lower cervical spine combined spinal cord injury.</p><p><b>METHODS</b>The clinical data of 54 patients of lower cervical spine fracture and dislocation were retrospectively analyzed. There were 29 cases with vertebral body compressive fracture and dislocation, 7 cases with vertebral body bursting fracture and dislocation, 3 cases with unilateral facet dislocation, 15 cases with bilateral facet dislocation. All cases were associated with spinal cord injury. According to American Spinal Injury Association (ASIA) grades, 21 cases were in A grade, 5 cases in B grade, 22 cases in C grade and 6 cases in D grade. All patients had surgical reduction, decompression, stabilization and fusion, 43 cases in anterior approach and 11 cases in posterior approach.</p><p><b>RESULTS</b>All patients were followed up in 12 to 36 months, the mean follow-up time was 18 months. There were no great vessels, trachea, esophagus or spinal cord iatrogenic injury. There were no pull-out and breakage of screws or plates. Fusion was achieved in all patients at an average of 12 weeks postoperatively. There were no pseudarthrosis or bone nonunion. Of all the patients, 96.3% were acquired completely reduction and the normal intervertebral height and lordosis were maintained. Patients with complete spinal cord had no neurologic recovery, but they felt relief from upper limb pain or numb. Incomplete spinal cord lesions improved on average 1-2 Frankel grade after surgery.</p><p><b>CONCLUSIONS</b>For lower cervical spine fracture and dislocation, an ideal anatomy reduction can be obtained with either anterior or posterior approach surgery. It is important to select a suitable surgical approach according to different types of cervical fracture and dislocation.</p>

Effect of nitric oxide synthase inhibitor on proteoglycan metabolism in repaired articular cartilage in rabbits / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To study the effect of nitric oxide synthase inhibitor, S-methyl thiocarbamate (SMT), on proteoglycan metabolism in repaired articular cartilage in rabbits.</p><p><b>METHODS</b>Twenty-four male New Zealand white rabbits, aged 8 months and weighing 2.5 kg+/-0.2 kg, were used in this study. Cartilage defects in full thickness were created on the intercondylar articular surface of bilateral femurs of all the rabbits. Then the rabbits were randomly divided into 3 groups (n=8 in each group). The defects in one group were filled with fibrin glue impregnated with recombinant human bone morphogenetic protein-2 (rhBMP-2, BMP group), in one group with fibrin glue impregnated with rhBMP-2 and hypodermic injection with SMT (SMT group) and in the other group with nothing (control group). All the animals were killed at one year postoperatively. The tissue sections were stained with safranine O-fast green and analyzed by Quantiment 500 system to determine the content of glycosaminoglycan through measuring the percentage of safranine O-stained area, the thickness of cartilages and the mean gray scale (average stain intensity). Radiolabelled sodium sulphate (Na(2)(35)SO(4)) was used to assess the proteoglycan synthesis.</p><p><b>RESULTS</b>At one year postoperatively, the percentage of safranine O-stained area, the mean gray scale and the cartilage thickness of the repaired tissues in SMT group were significantly higher than those of BMP group (P<0.01) and the control group (P<0.05). Result of incorporation of Na(2)(35)SO(4) showed that the proteoglycan synthesis in SMT group was higher than those of BMP group and the control group (P<0.01).</p><p><b>CONCLUSIONS</b>SMT, a nitric oxide synthase inhibitor, can significantly increase the content of glycosaminoglycan and proteoglycan synthesis, and computer-based image analysis is a reliable method for evaluating proteoglycan metabolism.</p>

Treatment of spondylolysis and spondylolisthesis with posterior STB thoracolumbar transpedicular screw-plate spine fixation system / 中华外科杂志

<p><b>OBJECTIVE</b>To observe the clinical effect of a self-designed posterior STB thoracolumbar transpedicular screw-plate system in the treatment of spondylolysis and spondylolisthesis.</p><p><b>METHODS</b>This STB screw-plate system is developed with titanium alloy (TC4, Ti6Al4V). During December, 1999 and January, 2001, this system was applied in 51 cases, including lumbar spondylolysis and spondylolisthesis (36 cases), degenerative lumbar instability (15 cases). The patients were aged 22 - 78 years, mean age: 47.5 - years; among them there were 14 male cases, 37 female cases; There were 15 cases degenerative spondylolisthesis with grade I-II slip, 36 cases of spondylolysis and spondylolisthesis, including 34 cases with grade I-II slips and 2 cases with grade III slips; single level of 33 cases, two levels 3 cases. Decompression was performed for the 43 cases with interbody fusion using iliac crest or bilateral-lateral fusion using demineralized bone matrix and 8 cases were fixed with demineralized bone matrix fusion without decompression.</p><p><b>RESULTS</b>All the operations heeded about 60 - 120 minutes, and during the operations bleeding amounts were 200 - 500 ml. The cases completely recovered to work or normal action after 3 months of surgeries. 46 of all cases were achieved to satisfactorily reduction and clinical effect, 5 cases of grade II-III remained incomplete reduction (grade I slip).</p><p><b>CONCLUSION</b>This STB system has advantages of biomechanical stability and reduction capability and its effect in clinical application is undoubtedly positive.</p>