2006年 · 第09卷第06期

Abstract：Objective: To analyze the data of trauma patients with thoracic injury in the earthquake of Bam admitted to hospitals of Tehran University of Medical Science (TUMS)for better understanding the type and consequence of thoracic injuries in a major earthquake.Methods: After Bam earthquake registering 6.5 on the Richter scale, 526 trauma patients were admitted to hospitals of TUMS. Among them, 53 patients sustained thoracic injury.Results: This group was composed of 21 females (39.6%) and 32 males (60.4%). Fifteen patients (28.3%) had isolated chest injuries. Rib fracture (36.4%) was the most common injury in our patients and haemo/pneumothorax (25.5%) followed. Superficial injury was the most common accompanying injury. Multipletrauma patients with chest injury had higher injury severity score (ISS) versus patients with isolated chest injury (P =0.003).Conclusions: Chest wall injuries and haemo/pneumothorax comprise a considerable number of injuries in survival victims of earthquakes. Consequently, the majority of these patients can be treated with observation or tube thoracostomy. We should train and equip the health workers and members of rescue teams to treat and manage these patients in the field。

Abstract：Objective: To study the effect of internal fixation with absorbable pins on treatment of displaced radial head fractures.Methods: From May 1999 to May 2004, 16 patients with displaced radial head fractures (Mason types Ⅱ and Ⅲ) were treated with internal fixation by absorbable pins.The duration of follow-up averaged 22.6 months (12-58 months). The outcome was assessed on the basis of elbow motion, radiographic findings and the functional rating score delineated by Broberg and Morrey.Results: All fractures healed within 10 months without avascular necrosis of radial head. The mean elbow flexion loss was 15°(0°-35°), and pronation and supination decreased by 10° (0°-30°) on average compared with those of the contralateral elbow. Five patients had an excellent result, 6 a good result, and 3 a fair result according to the criteria of Borberg and Morrey.Conclusions: Internal fixation with absorbable pins is an effective method in treating displaced radial head fractures. It can maintain the biomechanical stability of forearm, improve the elbow function and avoid second operation。

Abstract：Objective: To induce adipocyte differentiation in vitro by adipose-derived stromal cells (ASCs) harvested from transgenic mice with green fluorescent protein (GFP)and assess the possibility of constructing adipose tissues via attachment of ASCs to type Ⅰ collagen scaffolds.Methods: Inguinal fat pads from GFP transgenic mice were digested by enzymes for isolation of ASCs (primary culture). After expansion to three passages of ASCs, the cells were incubated in an adipogenic medium for two weeks, and the adipocyte differentiation by ASCs in vitro was assessed by morphological observation and Oil Red O staining. Then they were attached to collagen scaffolds and co-cultured for 12 hours, followed by hypodermic implantation to the dorsal skin of nude mice for 2 months. The newly-formed tissues were detected by HE staining.Results: The cultured primary stem cells were fibroblast-like and showed active proliferation. After being incubated in an adipocyte differentiation medium, the lipid droplets in the cytoplasm accumulated gradually and finally developed into mature adipocytes, which showed positive in Oil Red O staining. A 0.5-cm3 new tissue clot was found under the dorsal skin of the nude mice and it was confirmed as mature adipose tissues by fluorescent observation and HE staining.Conclusions: ASCs can successfully differentiate adipose tissues into mature adipocytes, which exhibit an adipocyte-like morphology and express as intracytoplasmic lipid droplets. It is an efficient model of adipose tissues engineered with ASCs and type Ⅰ collagen scaffolds。

Abstract：Objective: To explore the clinical characteristic of the multiple-ligament injured knee and evaluate the protocol,technique and outcome of treatment for the multipleligament injured knee.Methods: From October 2001 to March 2005, 9 knees with combined anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) tears in 9 patients were identified with clinical and arthroscopic examinations. Of them, 5 knees were combined with ruptures of posteromedial corner (PMC) and medial collateral ligament (MCL), 4 with disruptions of posterolateral corner ( PLC), 2 with popliteal vascular injuries and 1 with peroneal nerve injuries. Six patients were hospitalized in acute phase of trauma, 2 received repairs of popliteal artery and 4 had repairs of PMC and MCL. Reconstructions of ACL and PCL with autografts under arthroscope were performed in all patients at 4 to 10 weeks after trauma,including reconstruction of PLC with the posterior half of biceps femoris tendon tenodesis in 4 patients and reconstructions of PMC and MCL with femoral fascia in 1 patient.Results: No severe complications occurred at early stage after operation in the 9 patients. All of them were followed up for 10-39 months with an average of 23. 00 months ± 9.46 months. Lysholm score was 70-95 with an average of 85.00 ± 8.29. International Knee Documentation Committee (IKDC) score was from severely abnormal (Grade D) in 9 knees at initial examination to normal (Grade A) in 2 knees, nearly normal (Grade B ) in 6 knees and abnormal in 1 knee at the last follow-up. Of the 9 patients, 7 returned to the same activity level before injury and 2 were under the level.Conclusions: The multiple-ligament injured knee with severe instability is usually combined with other important structure damages. Therefore, careful assessment and treatment of the combined injuries are essential. Reconstructions of ACL and PCL under arthroscope, combined with repairs or reconstructions of the extraarticular ligaments simultaneously or in stages,have advantage of minimal trauma in surgery and satisfactory outcome。

Abstract：Objective: To identify the biomechanical feasibility of the thoracic extrapedicular approach to the placement of screws.Methods: Five fresh adult cadaveric thoracic spine from T1 to T8 were harvested. The screw was inserted either by pedicular approach or extrapedicular approach.The result was observed and the pullout strength by pedicular screw approach and extrapedicular screw approach via sagittai axis of the vertebrale was measured and compared statistically.Results: In thoracic pedicular approach, the pullout strength of pedicle screw was 1001.23 N ± 220 N (288.2-1561.7N) and that of thoracic extrapedicular screw approach was 827.01 N ± 260 N when screw was inserted into the vertebrae through transverse process, and 954.25 N ± 254 N when screw was inserted into the vertebrae through the lateral cortex of the pedicle.Compared with pedicular group, the pullout strength in extrapedicular group was decreased by 4.7% inserted through transverse process (P＞0.05) and by 17.3% inserted through the lateral cortex (P ＜0.05). The mean pullout strength by extrapedicular approach was decreased by 11.04% as compared with pedicular approach (P＜0.05).Conclusions: It is feasible biomechanically to use extrapedicular screw technique to insert pedicular screws in the thoracic spine when it is hard to insert by pedicular approach。

Abstract：Objective: To explore the patterns of innervation of cervical facet joints and determine the pathways from facet joints to dorsal root ganglions (DRGs) in order to clarify the causes of diffuse neck pain, headache, and shoulder pain.Methods: Forty-two male Sprague-Dawley rats,weighing 250-300 g, were randomly divided into three groups: Group A ( n = 18), Group B ( n = 18), and Group C (n = 6 ). Under anesthesia with intraperitoneal pentobarbital sodium (45 mg/kg body weight), a midline dorsal longitudinal incision was made over the cervical spine to expose the left cervical facet joint capsule of all the rats under a microscope. The rats in Group A underwent sympathectomy, but the rats in Group B and Group C did not undergo sympathectomy. Then 0.6 μl 5 % bisbenzimide (Bb) were injected into the C1-2, C3-4 and C5-6 facet joints of 6 rats respectively in Group A and Group B. The holes were immediately sealed with mineral wax to prevent leakage of Bb and the fascia and skin were closed. But in Group C, 0.9% normal saline was injected into the corresponding joint capsules. Then under deep reanesthesia with intraperitoneal pentobarbital sodium (45 mg/kg body weight), C1-C8 left DRGs in all rats and the sympathetic ganglions in Group B were obtained and the number of the labeled neurons was determined.Results: Neurons labeled with Bb were present in C1-C8 DRGs in both Group A and Group B, and sympathetic ganglions in Group B. In the C1-2 and C3-4 subgroups,labeled neurons were present from C1 to C8 DRGs, while in C5-6 subgroups they were from C, to C8. The number of Bb ( + ) neurons after sympathectomy was not significantly different in the injected level from that without sympathectomy. But in the other levels, the number of Bb ( + ) neurons after sympathectomy was significantly less than that without sympathectomy.Conclusions: The innervation of the cervical facet joints is derived from both sensory and sympathetic nervous system, and DRGs are associated with sympathetic ganglions through nerve fibers outside the central nerve system。

Abstract：Objective: To evaluate the compositional variation of fibrous callus in the fracture site and the joint cavity and joint cartilage after being transplanted in the muscle pouch.Methods: Thirty 2-month-old New Zealand white rabbits (weighing 1-1.5 kg) were randomly divided into two groups: a callus transplantation group (Group A, n =15) and a cartilage transplantation group ( Group B, n =15). In Group A, closed radius fracture was made and the autologous fibrous callus was transplanted in the right knee joint cavity at 12 days postoperatively. In Group B, the right knee joint cartilage of the animals was transplanted in the autologous back muscle pouches under anesthesia. Then all the animals were killed by overdose anesthetic 3 weeks after transplantation. And the transplanted fibrous callus,the healed bones in the fracture sites and the transplanted joint cartilage were obtained for assessment of compositional variation.Results: Pure fibrous composition was found in the callus at the fracture sites in Group A at 12 days postoperatively. And for 11 out of the 15 animals, the fibrous callus was transformed into cartilaginous tissues after 3 weeks of transplantation, but the fibrous callus was absent in the other 4 animals. The fibrous calluses at the original site and the fracture locus were differentiated into bony tissues. Bony tissue transformation was found in the transplanted joint cartilages in the muscle pouch of all the animals in Group B.Conclusions: The fracture sites or joint cavity may facilitate callus differentiation in different ways: the former is helpful for osteogenesis while the latter for the development and maintenance of cartilages, and the muscle pouch is inclined to induce the osteogenic phenotype for cartilages。

Abstract：Objective: To explore the effect of surgical treatment on complex acetabular fractures.Methods: The data of 46 patients (38 males and 8 females, aged 16-75 years, mean = 38. 5 years ) with complex acetabular fractures, who were admitted to our hospital from January 1998 to December 2005, were analyzed retrospectively in this study. According to Letournel rules, posterior wall and posterior column fractures were found in 11 patients, transverse and posterior wall fractures in 13, T-type fracture in 4, both columns fracture in 10, and anterior column and posterior transverse fracture in 8. The choice of surgical approach was based on the individual fractures, which included ilioinguinal approach in 5 patients, Kocher-Langenbech approach in 7, combined approach in 26, and extended iliofemoral approach in 8.Results: All the patients were followed up for 3.5 years averagely. The clinical outcomes were analyzed with Harris hip score and radiography. In 36 patients (78.3%), the surgical procedure was successful (Harris hip score ＞ 80 points). The rate of excellent and good was about 86 %.Conclusions: The keys to increase the effectiveness of surgical treatment on acetabular fractures are correct preoperative classification of factures and choices of appropriate surgical approach and time。

Abstract：Objective : To investigate the effect of early total hip arthroplasty for severe displaced acetabular fractures.Methods: Total hip arthroplasty was performed on 17 cases of severe fracture of the acetabulum from 1997 to 2003. The mean follow-up was 2.1 years (1-6 years) and the average period from fracture to operation was 8 days (5-21 day). The average age of the patients was 53 years (26-69 years).Results: At the final follow-up the Harris hip score averaged 82(69-100) points and 15 cases have got a good outcome. There was one case of heterotopic bone formation. There were no radiographic evidences of late loosening of the prosthesis. One patient had severe central displacement of the cup.Conclusions: In patients with severe displaced acetabular fractures, particularly in elderly patients, early total hip arthroplasty is probably an alternative efficient way to achieve a painless and stable hip。

Abstract：Objective: To inquire into the therapeutic effectiveness of free iliac crest grafts with periosteum on old acetabular defects.Methods: From February 1996 to June 2005, 9 patients were treated with free iliac crest grafts with periosteum to reconstruct old acetabular defects. There were 7 males and 2 females and the average age was 41.3 years. The acetabular defects were caused by traffic accidents in 6 cases and fall injury in 3 cases. The time from injury to treatment was 4-13 months and averaged 8 months. Intraoperatively we firstly removed the acetabular fracture fragments of the posterior wall. The femoral head was then reducted. Bone graft was harvested from the iliac crest with periosteum, which was sculpted with a rongeur to conform to the defect. The concave (iliac fossa) side of the graft was placed toward the femoral head. The graft was securedly fixed by two to three leg screws.Results: Postoperative syndrome was not found in any of the cases. Harris' score system showed that the score raised from 32. 3 points preoperatively to 81 points postoperatively. The hip function was evaluated as excellent in 3 cases, good in 4 cases and fair in 2 cases.Conclusions: Although this procedure could not exactly reproduce the anatomy of the hip joint, it enables to restore the posterior stability, provide bone-stock for the hip joints and prevent dislocation of the femoral head。

Abstract：Objective: To explore the operative indications and operative methods of primary total hip arthroplasty for acetabular fracture and to observe the clinical curative effect.Methods: We retrospectively summarized and analyzed the traumatic conditions, fracture types, complications,operative time, operative techniques, and short-term curative effect of 11 patients( 10 males and 1 female, with a mean age of 42. 4 years ) with acetabular fracture who underwent primary total hip arthroplasty.Results: The patients were followed up for 6-45 months ( mean = 28 months). Their average Harris score of postoperative hip joint was 78.Conclusion: Under strict mastery of indications,patients with acetabular fracture may undergo primary total hip arthroplasty, but stable acetabular components should be made。

Acetabular fractures are complex and special intraarticular fractures. For most orthopaedic surgeons management of acetabular fractures is hard and challenging because the fractures are the results of high-energy trauma, and usually accompany with severe associated injuries. In addition, these fractures are uncommon except in a few trauma centers. The number of cases a surgeon can encounter is scarce。

Abstract：Anatomic structure of acetabular fractures are complex and operative exposure and fixation are extremely difficult.For those obviously displaced acetabular fractures, close reduction is doomed to cause deformative healing. Open reduction with internal fixation (ORIF) not only results in anatomic reduction, but also brings complications. No matter which method will be adopted, traumatic arthritis or avascular necrosis of femoral head might occur. In order to treat acetabular fractures more effectively, orthopedic surgeons should be required to fully master the acetabular anatomy, biomechanics, classification and the necessary knowledge for complication prevention。

Abstract：Objective: To evaluate the efficacy and significance of posterolateral fusion in preventing failure of shortsegment stabilization for the treatment of thoracolumbar burst fractures.Methods: Sixty patients with thoracolumbar burst fractures were included in the study. The patients were classified into two groups ( n = 30 in each group). In Group A, patients were treated in our hospital with short-segment instrumentation via posterolateral fusion with iliac bone. In Group B, patients were treated in other hospital with shortsegnent fixation without fusion. All cases came to our hospital for reexamination. There were 18 males and 12 females in Group A with a mean age of 42.3 years (range,24 to 52 years) and 16 males and 14 females in Group B with a mean age of 41.5 years ( range, 19 to 54 years).Radiographic ( Cobb angle, kyphosis of the vertebral body,and sagittal index ) and clinical outcomes (Low Back Outcome Score ) were analyzed after an average follow-up of 16 months.Results: After operation, Cobb angle was reduced from 19.3° to 3. 1°in Group A and from 19. 1°to 3.3°in Group B (P ＞ 0.05). It was 5.9° in Group A and 11.9°in Group B at the final follow-up (P ＜ 0.01). Its average loss of correction was 2.8° in Group A and 8.6° in Group B. Average kyphosis of the vertebral body was reduced from 21.3 ° to 6.2 ° in Group A and from 21.7 °to 7.4° in Group B (P ＞ 0.05). It was decreased to7.9° in Group A and 13.5° in Group B at the final follow-up ( P ＜ 0.01 ).Its average loss of correction was 1.7° in Group A and 6.1 °in Group B. Sagittal index was reduced from 21.3° to 3.6° in Group A and from 20. 5° to 3.8° in Group B (P ＜0.05). It was decreased to 5. 1 ° in Group A and 9.8° in Group B at the final follow-up (P ＜ 0. 01 ). Its average loss was 1.5° in Group A and 6.0° in Group B. In Group A, 73.3 % of patients had an excellent result based on Low Back Outcome Score system, while that in Group B was only 43.3 %.Conclusions: Posterolateral fusion is an effective measure to prevent implant failure, and decrease loss of correction, posttraumatic kyphosis and neurogical deficit during the treatment of thoracolumbar burst fractures.Short-segment fixation of thoracolumbar burst fractures without fusion obviously increases failure rate and it is not an optional procedure。