2006年 · 第09卷第03期

Abstract：Objective: To explore a good way of the reconstruction of severe tibial shaft fractures by using different flaps and external fixators.Methods: Eighty-five patients of Type ⅢC tibial shaft fractures with average age of 42.5 years were treated in our hospital from 1990 to 2005. Injuries were caused by motorcycle accidents in 66 patients, by machine accidents in 16 patients, and by stone bruise in 3 patients. The management procedures consisted of administration of antibiotics, serial debridment, bone grafting if needed,application of different flaps, such as free thoracoumbilical flaps, fasciocutaneous flaps, saphenous neurocutaneous vascular flaps, sural neurocutaneous vascular flaps and gastrocnemius muscular flaps, and different external fixations, for instance, half-ring fixators, unilateral axial dynamic fixators, AO fixators, Weifang fixators, and Hybrid fixators. The average follow up was 6.3 years.Results: All flaps survived. Eighty-three cases had bone healed. The average bone healing time of different external fixations was 5.5 months in 47 cases with half-ring fixators, 9.2 months in 4 cases treated with unilateral axial dynamic fixators, 8.5 months in 6 cases with AO fixators,10.7 months in 16 cases with Weifang fixators, and 7.8months in 10 cases with assembly fixators. Except half-ring fixation, other fixations all needed necessary bone graft.Two cases treated with unilateral axial dynamic fixators had nonunion of bone and developed osteomyelitis. The wounds healed after the removal of the fixators and immobilization by plaster. The last follow up examination showed ankle and knee motion was normal and no pain was noted.Conclusions: The combination of half- ring external fixators with various flaps provides good results for Type ⅢC tibial shaft fractures。

Abstract：Objective: To evaluate the clinical feasibility and effect of the computer-assisted auto-frame navigation system for distal locking of tibial intrameduilary nails.Methods: The hardware components of the system included a PC computer with a monitor, auto mechanical stereotactical locating cubic frame, foot holder and localization operative apparatus. Special navigation software can be used for registration of X-ray fluoroscopic images and real-time controlling navigation of tools.Twenty-one cases of close tibial and fibular fractures were treated with closed intramedullary nailing, 6 of which involved in middle third, 12 in middle and lower third, 3 in lower third. C-arm alignment and registration time,fluoroscopic time and drilling time involved in the locking procedure were recorded. The size of unreamed or reamed tibial nails ranged from 8/300-11/330.Results: All distal holes except 1 were locked successfully. In 9 of 41 locked holes (21.95%), the drill bit touched the canal of locking hole without damage of the nail and clinical consequences. The fluoroscopy time per pair of screws was 2.23 s ± 0.31 s.Conclusions: The computer-assisted auto-frame navigation system for distal locking is well designed, easy to operate and do not need additional instruments during the procedure. The developed system enables the physician to precisely navigate surgical instruments throughout the anatomy using just a few computer-calibrated radiographic images. The total time of x-ray exposure per procedure can be significantly reduced。

Abstract：Objective: To determine the efficacy of polylactic acid glue in preventing epidural scar adhesion after laminectomy in rabbits.Methods: Twenty-four apanese white rabbits underwent laminectomy (including the attached ligaments)at L2 and Ls. After laminectomy at L5, polylactic acid glue was sprayed on the dura and nerve roots and this segment was taken as the experimental group. After laminectomy at L2 , nothing was used and this segment was enrolled as the self control group. Four rabbits were killed every two weeks postoperatively till the end of the experiment at 12weeks. Then the operated spine was observed grossly,histologically and ultrastructurally to check the degree of scar formation, the status of epidural scar adhesion, the absorption of the glue, and the intracellular structure of fibroblasts.Results: The glue coagulated immediately after spraying and showed excellent hemostatic effect. The glue membrane was easy to be taken away from the dura mater of the samples for 2 weeks and there were no cells in the epidural space in the experimental group. But the dura mater was covered by hematoma in the control group,which formed mild adhesion, with fibroblasts proliferating actively. In the 4th week, some glue shivers remained in the epidural space with fibroblasts increasing a little, and the dura mater was smooth in the experimental group.However, in the control group, the formed scar was fragile and conglutinated with the dura mater diffusely and fibroblasts were much more than those in the experimental group. In the 6th-12th weeks, there was a potential interspace between the scar and the dura mater, and the polylactic acid glue was absorbed completely in the experimental group. Much tough scar was found in the control group, which was very difficult to dissect from the dura mater and the surrounding tissues. From the ultrastructural observation of the fibroblasts, the nucleus became much bigger and the rough endoplasmic reticulum was much more plentiful in the control group than that in the experimental group.Conclusions: Polylactic acid glue can effectively reduce epidural cicatrization and adhesion。

Abstract：Objective: To investigate the effect of autocontrol micromotion locking nail (AMLN) on experimental fracture healing and its mechanism.Methods: 16 goats undergoing both sides of transverse osteotomy of the femoral shafts were fixed intramedullary with AMLN and Gross-Kempf (GK) nail,respectively. The follow-up time was 7, 14, 28 and 56days. Roentgenographic, biomechanical, histological,scanning electromicroscopic and biochemical analyses were done.Results: ( 1 ) The strength of anticompression,antiflexion and antitorsion in the fractural end in the AMLN-fixed group was higher than that of GK nail-fixed group; whereas, the rate of stress shelter in the fractured end decreased significantly (P ＜ 0.01 ). (2) The content of the total collagen, insoluble collagen, calcium and phosphate in the AMLN-fixed group was higher than that in the GK nail-fixed group ( P ＜ 0.05 ). ( 3 ) Histological observation and quantitative analysis of calluses revealed that AMLN could promote the growth of bridge calluses and periosteum calluses. Hence the facture healing and remolding process achieved early, which was much better than traditional GK nail fixation. (P ＜ 0.05). ( 4 ) 7-14days postoperation, the calluses of AMLN-fixed group was flourish and camellarly arranged and the collagen fibril formed constantly in the absorption lacuna of bone trabecula. 28-56 days postoperation, the collagen fibril was flourish around the absorption lacuna and was parallel to the bone's longitudinal axis. Active bony absorption and formation were seen, so was remolding and rebuilding.Haversian system was intact and the bony structural net was very tenacious because of the deposition of calcium salt.None of the above findings was observed in the GK nailfixed group.Conclusions: The design of AMLN accords well with the plastic fixation theory. As the geometry ametabolic system constituted by the intramedullary fixation instruments and the proximal and distal end of the fracture is very firm and stable, the disturbance to the physical stress distributed in the fractural end is light. The generation and conduct of the intermittent physical stress between the fractural parts could reach the balance between stress conduct and stress protection. The feature that the healing and remoiding take place at the same time speeds up the fractural healing process。

Abstract：Objective: To compare the mechanical properties of point contact-dynamic compression plate (PC-DCP) and its effects on cortical bone perfusion with that of dynamic compression plates (DCP) in goat tibiae.Methods: Twenty pairs of matched fresh goat tibiae were used. A transverse fracture model was established.The fractures with a 3mm interspace between the fracture ends were subject to fixations with the DCPs and the PCDCPs respectively, then the four-points bending tests and the torsion tests were conducted to compare the mechanical properties of the PC-DCP with that of DCP. Another 13sexually mature goats underwent fixations with the DCPs and the PC-DCPs, respectively, at the mid-shafts of the intact bilateral tibiae. Ischemic zones were observed at four time points (1 day, 2, 6, and 12 weeks after operation)using disulphine blue staining technique.Results: There were no significant differences in mechanical properties, such as bend- and torsionresistance, between the DCPs and the PC-DCPs. One day,2, and 6 weeks after operation, on the side of DCP fixation, outer cortical bone iscbemia under the plate persisted, and this condition did not reverse until 12 weeks after operation. However, on the side of PC-DCP fixation,cortical bone ischemia occurred only in the periphery of the screw holes and at the contact sites of the PC NUTs 1 day after operation, and it disappeared at 2 weeks after operation.Conclusions: The PC-DCP has similar biomechanical properties of the DCP, but is less detrimental to local bone blood circulation than the conventional plates。

Abstract：Objective: To explore the effects of hyperbaric oxygen (HBO) treatment on the neuronal apoptosis at an earlier stage and the expressions of Cytochrome C (Cyt C), Bcl-2 (B-cell lymphoma-2 family) and Bax (Bcl-2associated X protein) in rat brain tissues after traumatic brain injury (TBI).Methods: Forty adult rats were divided into two groups, i.e., Group A ( the rats with untreated TBI) and Group B ( rats with HBO treatment after TBI). Sections of brain tissues of these two groups were then detected at 3,6,12,24,72 hours after TBI by immunohistochemistry and electronmicroscope, respectively.Results: HBO treatment could up-regulate the expression of Bcl-2 within 72 hours, reduce the release of Cyt C from mitochondria, attenuate the formation of dimeric Bax and alleviate the mitochondrial edema within 24 hours after TBI.Conclusions: HBO treatment can alleviate neuronal apoptosis after TBI by reducing the release of Cyt C and the dimers of Bax and up-regulating the expression of Bcl-2。

Abstract：Objective: To study the influence of separation of distal tibiofibular syndesmosis on ankle joint and to compare various operative methods so as to find suitable stabilization for separated distal tibiofibular syndesmosis.Methods: From July 1997 to July 2002, we treated 87 patients (64 males and 23 females, aged 18-54 years)with separation of distal tibiofibular syndesmosis, among whom, 79 were combined with fracture of malleolus.Manipulative reduction, internal fixation with cancellous screws and external fixation with plaster support were performed on 37 patients, fixation with plate and screws for fibular fracture and fixation with cancellous screws for distal tibiofibular syndesmosis on 34 patients, and repair of the distal tibiofibular ligaments with tendon of peroneus longus, reduction of the separated distal tibiofibular syndesmosis, and fixation with cancellous screws on 16patients. The ankle joint had been dorsiflexed for 30° when the distal tibiofibuiar syndesmosis was fixed with cancellous screws. And the cancellous screws were taken out at 8-10weeks after operation.Results: These patients were followed up for at least two years. The curative effects were assessed according to the complaints of the patients and the contour, function and radiogram of the ankle joint: excellent in 55 patients (63%), good in 18 patients (21%), and fair in 14 patients (16%). Separation of distal tibiofibular syndesmosis recurred in 2 patients, who underwent a reoperation for repairing the distal tibiofibular ligaments with tendon of peroneus longus and recovered. One cancellous screw was broken off. No necrosis developed in the anterior skin of the ankle mortise.Conclusions: Separation of distal tibiofibular syndesmosis can be treated with various reasonable operations. Repair with tendon of the peroneus longus can get excellent outcomes for complete separation of the distal tibiofibular syndesmosis。

Abstract：Objective: To investigate the effect of Radix Paeoniae Rubra (RPR) on the expression of heme oxygenase ( HO-1 ) and induced nitric oxide synthase (iNOS) in endotoxininduced acute lung injury in rats and its protective mechanism.Methods: Forty Wistar rats were divided randomly into 5 groups with 8 rats in each group: saline control group ( NS group ), lipopolysaccharide group ( LPS group), RPR-treatment group, RPR-prevention group and Herin group. The effect of RPR on protein content, the ratio of neutrophiles in bronchoalveolar lavage fluid,malondialdehyde (MDA) content in the lung and the activity of serum NO were observed. Arterial blood was drawn for blood-gas analysis. The expression of HO-1 and iNOS in lung tissues was detected by immunohistochemitry and morphometry computer image analysis. The histological changes of the lung were observed under light microscope.Results: Compared with that in NS group, the expression of HO-1 and iNOS was markedly increased in LPS group (P ＜ 0.01). In RPR-treatment, RPR-prevention, and Hemin groups, the expression of iNOS was significantly lower, while the expression of HO-1 was higher than that in LPS group (P ＜0.05). The protein content,the ratio of neutrophiles in bronchoalveolar lavage fluid,the content of MDA and the activity of serum NO in LPS group were significantly higher than those in NS group (P ＜ 0.01 ). There was a significant decrease in the level of arterial bicarbonate and partial pressure of oxygen in the LPS group (P＜0.01); these parameters of lung injury however, were significantly lower in RPR-treatment, RPR-prevention, and Hemin groups than LPS group (P ＜0.05or P ＜ 0.01). The pathologic changes of lung tissues were substantially attenuated in RPR-treatment, RPR-prevention, and Hemin groups than LPS group.Conclusions : The high expression of HO-1 reflects an important protective function of the body during lipopolysaccharide-induced acute lung injury. The protective effect of RPR on lipopolysaccharide-induced acute lung injury is related to the inhibition of iNOS expression and the induction of HO-1 expression。

Abstract：Objective: To detect the levels of dipalmitoyl phosphatidyl choline (DPPC) in the sputum of the patients with acute cerebral injury without primary pulmonary injury after mechanical ventilation treatment.Methods: DPPC levels in sputum of 35 patients with acute cerebral injury but without pulmonary injury were detected with high performance liquid chromatography at the beginning of ventilation and 16-20 days, 21-40 days,and 41-60 days after ventilation, respectively.Results: There was no significant difference of the DPPC levels between 16-20 days after ventilation (3.36 ±0.49) and at the beginning of ventilation ( 3.37 ± 0.58 )(P＞0.05). The mean levels of DPPC decreased significantly at 21-40 days (2.87 mg/ml ±0.26 mg/ml, P ＜0.05) and 41-60 days (1.93 mg/ml ±0.21 mg/ml, P ＜0.01) after ventilation compared with that at the beginning of ventilation. At the same period, the peak inspiratory pressure and the mean pressure of airway increas ed significantly, whereas the static compliance and the partial pressure of oxygen in artery decreased significantly. Among the 25 patients who received ventilation for more than 20days, 8 (32%) had slightly-decreased partial pressure of oxygen in artery compared with that at the beginning of ventilation.Conclusions: Mechanical ventilation can decrease the DPPC levels, decrease the lung compliance and increase the airway pressure, even impair the oxygenation function in patients with acute cerebral injury. Abnormal DPPC is one of the major causes of ventilator-associated lung injury。

Subclavian vascular injury accounts for 1%-5 % of all vascular injuries. If not found in time or managed swiftly, subclavian vascular injury is likely to cause hemorrhagic shock and even death. From March of 1998 through August of 2003, a total of 15 cases with subclavian vascular injury were treated in our department. The details are described in this report。