Volume 11 · Issue 03 · 2008

Objective: To compare fatalities and injuries in road traffic crashes (RTC) in Iran with other countries. Methods: Data were obtained from national health sources of Iran. These data included population number, registered motor-vehicles number, number of RTCs and consequent fatalities and injuries from 1997 to 2006. Results: RTC fatality and injury rates increased from 1997 to 2005, but decreased in 2006. The overall men/women ratio in the RTC fatalities was 4.2:1. High RTC fatality rate of 39 per 100 000 population in Iran was almost the same as some other developing countries. In Iran, RTC fatalities in recent years were almost twice as much as the highest rate among the European countries. Conclusions: This investigation shows that in spite of reduction of RTC fatality in Iran in 2006, it is still one of the highest in the world. Moreover, this paper describes the state of RTC-related parameters in a developing country in comparison with the developed countries.

Objective: To identify radiographic predictors of residual low back pain (LBP) after laminectomy for lumbar canal stenosis (LCS). Methods: Clinical results and radiographic findings in 69 patients who underwent single level laminectomy for LCS were retrospectively reviewed. Patients who had an improvement in LBP scores evaluated by Japanese Orthopaedic Association (JOA) scoring system during the follow-up periods were classified as the recovery group, and others were classified as the non-recovery group. Patients’ clinical data and radiographic parameters like lordosis angle, range of motion and intervertebral rotational angle were analyzed using binary logistic regression analysis to detect factors significantly related with the occurrence of residual LBP. Results: The average preoperative JOA score of 14.8 ± 5.05 improved to 21.59 ± 5.51 at the final follow-up. Binary logistic regression analysis revealed that significant pre-dictors of residual LBP were preoperative lumbar lordosis angle and range of motion. Conclusions: Our results suggest that patients with flat back and limited lumbar mobility before surgery tend to have poor results in terms of LBP. Therefore, these sagittal radiographic parameters should be taken into account when choosing laminectomy as the surgical option for LCS.

Objective: To observe the immune response after the transplantation of a deproteinized heterogeneous bone scaf-fold and provides the theoretic reference for clinical practice. Methods: The fresh pig bone and deproteinized bone were transplanted respectively to establish BABL/C thigh muscle pouches model of male mice and take the samples for detection at 1, 2, 4, 6 weeks after operation. Lymphocyte stimulation index, subset analysis, serum specific antibody IgG, cytokine detection and topographic histologic reaction after implantation were investigated. Results: After the transplantation of deproteinized bone, lymphocyte stimulation index, CD4+ and CD8+ T-lymphocyte subsets, serum specific antibody IgG and cytokines in deproteinized bone group were significantly lower than those in fresh pig bone group at each time point (P<0.05). The histological examination found that in fresh bone group at each time point, a large quantity of inflammatory cells infiltrated in the surrounding of bone graft, and they were mainly lymphocytes, including macrophages and monocytes. In deproteinized bone group, there were few inflammatory cells infiltration around bone graft one week after operation. The lymphocytes were decreased as time went by. At 6 weeks, fibroblasts and fibrous tissue grew into the graft, and osteoclasts and osteoprogenitor cells appeared on the verge. Conclusions: The established heterogeneous deproteinized bone has low immunogenicity and is a potentially ideal scaffold material for bone tissue engineering.

Objective: The conventional approaches for treatment of thoracolumbar diseases require extensive surgical exposure, often leading to postoperative pain and morbidity. Thoracoscopic-assisted surgery in these regions usually requires an extended recovery period due to the placement of drainage. We developed an innovative retroperitoneal-extrapleural approach to thoracolumbar involvement by an extra-diaphragmatic technique using dedicated instruments. Neither incision nor reconstruction of the diaphragm was necessary. Exposure to the lateral part of the thoracolumbar vertebrae could be achieved without crus resection. This study is aimed to evaluate the clinical outcomes of this new surgical procedure. Methods: A total of 9 cases (5 cases of thoracolumbar fracture-dislocation, 1 each of spinal infection, tumor, thoracolumbar scoliosis and ossification of posterior longitudinal ligament) were subjected to the study. The average age of the patients was 52.3 years. The results were compared with the control group consisting of thoracoscopic surgery subgroup (5 patients, mean age 52.1 years) and conventional surgery subgroup (12 patients, mean age 61.3 years). Results: Compared with the control group, the average period of bed confinement and mean intra-and post-operative blood loss decreased significantly. Pulmonary complications were avoided in all cases. The surgical time was shortened, postoperative pain was reduced, and early postoperative ambulation became possible. Conclusion: The diaphragm-preserving retroperitoneal-extrapleural approach that we developed is a valid minimally invasive alternative for the treatment of thoracolumbar diseases.

Objective: To explore suitable scaffold material for big segmental long bone defect by studying the properties of the prepared deproteinized bone. Methods: Cancellated bone were made as 30 mm × 3 mm × 3 mm bone blocks from inferior extremity of pig femur along bone trabecula. The deproteinized bone was prepared with an improved method. Their morphological features, components, cell compatibility, mechanical and immunological properties were investigated respectively. Results: Deproteinized bone maintained natural reticular pore system. The main organic material is collagen Ⅰ and inorganic composition is hydroxyapatite. It has good mechanical properties, cell adhesion rate and histocompatibility. Conlusion: This deproteinized bone can be applicable as scaffold for reparation of big segmental defect in long bone.

Objective: To probe the feasibility and efficacy of damage control orthopedics (DCO) in treating severe multiple injuries. Methods: A retrospective analysis was made on the clinical data of 41 patients (31 males and 10 females, aged 18-71 years, mean: 36.4) with multiple injuries admitted to our department and treated by DCO from January 1995 to December 2005. Results: As a first-stage therapy, devascularization of internal iliac arteries was performed in 29 patients with pelvic fractures combined with massive bleeding, including ligation of bilateral internal iliac arteries in 21 patients and embolization of bilateral internal iliac arteries in 8. And early external fixation of pelvis was performed in 10 patients. Ten patients with severe multiple injuries combined with femoral fractures were managed with primary debridement and temporal external fixation and 2 patients with spinal fractures combined with spinal cord compression received simple laminectomy. Thirty-one patients received definite internal fixation after resuscitation in intensive care unit. The overall mortality rate was 12.1% (5/41) with an average injury severity score of 41.4. The main causes of death were hemorrhagic shock and associated injuries. Complications occurred in 7 patients including acute respiratory distress syndrome in 3 cases, thrombosis of right common iliac artery in 1, subphernic abscess in 2 and infection of deep wound in lower extremity in 1. After treatment, all the patients got cured. Conclusions: Prompt diagnosis and integrated treatment are keys to higher survival rate in patients with severe multiple injuries. In this condition, DCO is an effective and safe option.

Objective: To study the expression regularity of vascular endothelial growth factor (VEGF) during the process of fracture healing, and the type of VEGF receptor expressed in the vascular endothelial cells of the fracture site. Methods: The fracture model was made in the middle part of left radius in 35 rabbits. The specimens from the fracture site were harvested at 8, 24, 72 hours and 1, 3, 5, 8 weeks, and then fixed, decalcified, and sectioned frozenly to detect the expression of VEGF and its receptor at the fracture site by in situ hybridization and immunochemical assays. Results: VEGF mRNA and VEGF expression was detected in many kinds of cells at the fracture site during 8 hours to 8 weeks after fracture. Flt1 receptor of VEGF was found in the vascular endothelial cells at the fracture site during 8 hours to 8 weeks after fracture, and strong expression of flk1 receptor was detected from 3 days to 3 weeks after fracture. Conclusions: The expression of VEGF and flt1 receptor appears during the whole course of fracture healing, especially from 1 to 3 weeks. Flk1 receptor is highly expressed in a definite period after fracture. VEGF is proved to be involved in the vascular reconstruction and fracture healing.

Objective: To evaluate the effect of autologous bone marrow mesenchymal stem cells (BMSCs) seeded bio-derived bone materials (BBM) combined with recombinant human bone morphogenetic protein-2 (rhBMP-2) in repairing defect of osteonecrosis of femoral head (ONFH). Methods: Early-stage osteonecrosis in the left hip was induced in 36 adult New Zealand white rabbits (provided by the Animal Center of Guangxi Medical University, Nanning, China) after core decompression and delivery of liquid nitrogen into the femoral head. Then the animals were divided into three groups according to the type of implants for bone repair: 12 rabbits with nothing (Group Ⅰ, the blank control group), 12 with BBM combined with rhBMP-2 (Group Ⅱ), and 12 with BMSCs-seeded BBM combined with rhBMP-2 (Group Ⅲ). At 4, 8, and 12 weeks after surgery, X-ray of the femoral head of every 4 rabbits in each group was taken, and then they were killed and the femoral heads were collected at each time point, respectively. Gross observation was made on the femoral heads. After hematoxylin and eosin staining, Lane-sandhu scores of X-ray and bone densitometry were calculated and the histomorphometric measurements were made for the new bone trabeculae. Results: At 12 weeks after surgery, two femoral heads collapsed in Group Ⅰ , but none in Group Ⅱ or Group Ⅲ. X-ray examination showed that the femoral heads in Group Ⅰ had defect shadow or collapsed while those in Group Ⅱ had a low density and those in Group Ⅲ presented with a normal density. Histologically, the defects of femoral heads were primarily filled with no new bone but fibrous tissues in Group Ⅰ . In contrast, new bone regeneration and fibrous tissues occurred in Group Ⅱ and only new bone regeneration occurrd in Group Ⅲ. Lane-sandhu scores of X-ray, bone mineral density and rate of new bone in trabecular area in Group Ⅲ were higher significantly than those of the other two groups. Conclusions: Our findings indicate a superior choice of repairing the experimental defect of ONFH with BMSCs-seeded BBM combined with rhBMP-2.

Objective: To investigate the clinical characteristics, treatment options and causes of misdiagnosis of ipsilateral femoral neck and shaft fractures. Methods: Among 20 patients with ipsilateral femoral neck and shaft fractures, 19 were treated operatively and 1 was treated conservatively. Sixteen cases of femoral shaft fractures were treated by open reduction and internal fixation with compressive plate, and 2 cases were treated with interlocking intramedullary nailing. Eighteen femoral neck fractures were treated with cannulated screws. Another patient was treated with proximal femoral nail to fix both the neck and shaft. Delayed diagnosis for femoral neck fractures occurred in 2 cases preoperatively. Results: A total of 19 patients were followed up. The follow up period ranged from 5 to 48 months with an average of 15 months. All the fractures were healed. Conclusion: For case of femoral shaft fracture caused by high energy injury, an AP pelvic film should be routinely taken. Once the femoral neck fracture is recognized, operative reduction and fixation should be performed in time. Femoral neck and shaft fractures should be fixed separately.

Objective: To study the use of a nerve "bypass" graft as a possible alternative to neurolysis or segmental resection with interposition grafting in the treatment of neuroma-in-continuity. Methods: A sciatic nerve crush injury model was established in the Sprague-Dawley rat by compression with a straight hemostatic forceps. Epineurial windows were created proximal and distal to the injurysite. An 8-mm segment of radial nerve was harvested and coaptated to the sciatic nerve at the epineurial window sites proximal and distal to the compressed segment (bypass group). A sciatic nerve crush injury without bypass served as a control. Nerve conduction studies were performed over an 8-week period. Sciatic nerves were then harvested and studied under transmission electron microscopy. Myelinated axon counts were obtained. Results: Nerve conduction velocity was significantly faster in the bypass group than in the control group at 8 weeks (63.57 m/s±5.83 m/s vs. 54.88 m/s±4.79m/s, P<0.01). Myelinated axon counts in distal segments were found more in the experimental sciatic nerve than in the control sciatic nerve. Significant axonal growth was noted in the bypass nerve segment itself . Conclusion: Nerve bypass may serve to augment peripheral axonal growth while avoiding further loss of the native nerve.