BACKGROUND: Re-injury of organism and sufficient of materials exist in the autologous transplantation of tendon to treat defected tendon following trauma. Carbon fiber artifical tendon, human hair tendon and other artifical tendons are also proved to be transplantable. But immunological rejection and biomechanical inadaptability exist following artifical tendons are transplanted. Therefore, the development of new human tendon substitute is the major problem to be solved at present.OBJECTIVE: To observe the porcine small intestinal submucosa as artificial tendon to repair 2 cm tendon defect of the 3rd toe of the left and right feet of chicken, and the immunological rejection and biomechanical adaptability following repair.DESIGN: A randomized and controlled animal experiment.SETTING: Department of Orthopaedics, Sixth Hospital Affiliated to Shanghai Jiaotong University.MATERIALS: Totally 45 Leghorn chickens, aged 12 weeks, of either gender, with body mass of 4.0 to 4.4 kg, were chosen.METHODS: This experiment was conducted at the Department of Orthopaedics, Sixth Hospital Affiliated to Shanghai Jiaotong University from September 2002 to June 2003. ① Totally 45 Leghorn chicken, aged 12 weeks, were randomly divided into 3 groups. The third toe of the left and right feet was chosen from 20 chicken respectively of autologous transplantation group and porcine small intestinal submucosa group, flexor digitorum profundus muscle tendon was cut off at middle phalanx, and 2 cm tendon defect model was created. The defected tendon in the autologous transplantation group was performed in situ suture; the defected tendon in the porcine small intestinal submucosa transplantation group was repaired with porcine small intestinal submucosa; There was not any treatment on the 5 Leghorn chicken in the blank control group. ② Histomorphologyl, transplantation immunology, biomechanics and functional recovery were measured at 3,6 and 9 weeks following tendon transplantation.MAIN OUTCOME MEASURES: ① Gross observation of operated toes of chicken and optical observation of grafts in each group. ② White blood cell (WBC) differential count at 3 days preoperation,3 days postoperation,and 1 week and 2 weeks postoperation. ③ Biomechanical test and functional recovery test of chicken in each group.RESULTS: Totally 45 chicken entered the stage of result analysis. ① At 9 weeks after operation, morphology of porcine small intestinal submucosa was basically the same as that of normal tendon by naked eyes; Under optical microscope, fibroblasts on the porcine small intestinal submucosa arranged in order along long-axis and collagen extracellular matrix appeared.② Within 2 weeks after operation, there was no significant difference of WBC measurement between porcine small intestinal submucosa transplantation group and autogolous transplantation group (P ＞ 0.05), suggesting that porcine small intestinal submucosa, as xenogenic material, has no obvious immunological rejection. ③ In the biomechanical test, biomechanical adaptability at postoperative 12 weeks was superior in the porcine small intestinal submucosa group to in the autologous transplantation group [(22.22±0.90),(20.78±0.94) ,P ＜ 0.05]. ④ In the test of functional recovery, there was no obvious difference of activity of metecarpophalangeal joint (P ＞ 0.05), the activity of proximal interphalangeal joint was superior in the blank control group to in the porcine small intestinal submucosa group and autologous transplantation group [(21.0±1.6)°, (15.1±1.7)° , (16.0±2.1)° ,P ＜ 0.05].CONCLUSION: There is no evidence of immunological rejection after porcine small intestinal submucosa is transplanted into the body of chicken. Therefore, porcine small intestinal submucosa can be used as the xenogenic material to repair tendon defect.

Objective To investigate the influence of low frequency micromovement induced by an external fixator with controlled micromovement device on callus formation and fracture healing. Methods 39 sheep were involved in the study. After transverse osteotomy with a gap of 2 mm was done at the mid-shaft of both tibias, the hind limbs were fixed with unilateral external fixators with controlled micromovement device. 10 days after osteotomy, one hind limb of the sheep was randomly selected to have micromovement. According to different micromovement frequencies, the sheep were randomly divided into 3 groups: Group A, 0.5 Hertz; Group B, 1 Hertz; Group C, 5 Hertz. The micromovement had an amplitude of 0.25mm and stopped by the end of the fourth postoperative week (30 min/d). The other hind limb of each sheep did not have micromovement and served as the control. Macrostructural and histological observations, radiographic examinations, and biomechanical tests were done respectively at 4, 6, 9 weeks after osteotomy. Results Macrostructural observations and X-ray examinations revealed a large amount of callus formation with a peak at the end of the fourth postoperative week in the 3 experimental groups. Histological analysis showed faster endochondral ossification and osteoid formation in the experimental groups than in the control by the sixth postoperative week, with the highest rate in Group B (1Hz). Biomechanical tests proved that the bending stiffness in the experimental groups was superior to that in the control, with the strongest in Group B (1 Hz). Conclusions Low frequency-micromovement at the fracture sites can promote callus formation and accelerate mineralization at the early stage of fracture healing. A frequency of 1 Hz can produce the best results.

Objective To investigate treatment method for existing and impending benign pathological femoral neck and trochanteric lesions.Methods A retrospective study wad done on 25 patients with benign proximal femur lesions treated between 2002 and 2004.All patients were treated with lesion curettage,cauterization,autografting and/or allografting.Then,dynamic condylar screw (DCS) or hip joint-span external fixator were selected according to the involved area of the lesion of the proximal femur.The duration of follow-up was mean 2.3 years (2-4 years).Results Sound bony union was seen on the radiographs of all patients by 3-6 months after surgery.There found no local recurrence or avascular necrosis of the femoral head,or complications like necrosis,infections or fractures.Function of the patients in the current series was graded excellent,assessed by the validated outcome measures MSTS-87,MSTS-93 and TESS lower extremity.Conclusion DCS or hip joint-span external fixator may be better alternative treatment of benign pathological femoral neck and trochanteric lesions,compared with conventional surgical methods such as simple bone grafting,traction and hip spica cast.

Objective To compare and analyze the biomechanical strengths of 4 different fixations for the posterolateral shearing tibial plateau fracture. Methods The posterolateral shearing fracture models were created in 40 synthetic tibia (SYNBONE, right) and randomly assigned into 4 groups. Group A was instrumented with 2 lag screws, group B with anteromedial LC-DCP, group C with lateral locking plate,and group D with posterolateral buttress plate. Vertical displacements of the posterolateral fragments and failure loads were measured under axial loads from 500 N to 1500 N. Results The vertical displacements in groups A, B, C and D were respectively(0. 459 ±0. 045) mm, (0. 365 ±0. 035) mm, (0. 264 ±0. 025)mm and (0. 128 ± 0. 018) mm under axial loads of 500 N, (1. 058 ± 0. 091 ) mm, (0. 882 ± 0. 053 ) mm,(0.551±0.053) mm and (0.440±0.068) mm under 1000 N, and (1.559±0.097) mm, (1.466±0. 079) mm, (1. 291 ±0. 077) mm and (0. 832 ±0. 130) mm under 1500 N. The differences between the 4 groups were statistically significant ( P ＜ 0. 05) . The loads to failure in groups A, B, C and D were respectively (1870 ± 156) N, (2520 ± 186) N, (2816 ± 190) N and (3465 ±210) N. The differences between the 4 groups were statistically significant ( P ＜ 0. 05 ). Conclusion The posterolateral buttress plate may be the biomechanically best fixation method for the posterolateral shearing tibial plateau fracture.

Objective To investigate the effect of radiation-induced heart injury on cardiac troponin I (cTnI)and endothelin-1(ET-1) and observe the preventive and therapeutic effect of fluvastatin. Methods Healthy female SD rats were randomly divided into three groups: control group(c), irradiation alone group(R) and fluvastatin therapeutic group (F). Rats of F group had been gastrogavaged with fluvastatin at dose of 20mg?kg -1?d -1 from 1week before irradiation to the end of the experiment. In C group and R group, rats were gastrogavaged with the same volume isotonic sodium chloride. The rats of R and F group were irradiated with accelerator linear at a dose of 20Gy thoracically. Rats were executed at 5,15,30d and 60d after irradiation, then cTnI in serum and ET-1 in blood plasma were detected. Results On 5d, the content of cTnI in R group increased significantly than that in C group(P

Objective To discuss clinical outcomes of extraperitoneal pelvic packing (EPP) plus external fixation for hemodynamically unstable pelvic fractures. Methods We used EPP plus external fixation to control 15 cases of hemodynamically unstable pelvic fractures from further damage. They were 6 males and 9 females. Their average age was (44. 0 ± 1.2) (38 to 56) years old. Their injury was caused by a traffic accident (13 patients) and falling from a great height (2 patients). According to the Tile classification,there were 3 cases of type B1, 2 cases of type B2-2, 5 cases of type C1, 3 cases of type C2, and 2 cases of type C3. All the 15 patients were hemodynamically unstable and had a hypovolemic shock. Results There was a statistically significant increase in systolic blood pressure, hematocrit and hemoglobin measured immediately after EPP( P < 0. 05) . However, the units of RBC transfusion significantly decreased( P <0.05) and there were no significant difference in pulse rate( P > 0. 05) . The average operation time was (32.0 ± 2.6) min(30 to 40 min). Five patients died (72. 0 ± 4.2) h after operation ( 1 to 7 d). There was no significant difference between the survivors and the non-survivors in systolic blood pressure, pulse rate,hemoglobin, ISS score, hematocrit and blood transfusion( P > 0. 05). But there was significant difference in age and time between injury and EPP ( P < 0. 05). Conclusions In emergency treatment of patients with the hemodynamically unstable pelvic fracture, especially those combined with hypovolemic shock, EPP plus external fixation can effectively control the massive venous (presacral venous plexus) and bone hemorrhage.The blood pressure and pulse rate can be restored by fluid replacement and blood transfusion. Consequently,this method may significantly improve the hemodynamical parameters and decrease the mortality.

Objective To report the preliminary results of treatment of fracture nonunion at the distal femur and the proximal tibia with Less Invasive Stabilization System (LISS). Methods From February 2003 to August 2004, LISS fixation and bone grafting were employed to treat 5 cases of fracture nonunion at the distal femur and 4 cases of fracture nonunion at the proximal tibia. The nonunion had resulted from failure of internal fixation in 7 cases, failure of external fixation in 1 and infection in 1. The history of nonunion lasted from 10 to 111 months (mean 29m). Results All the 9 patients were followed up for an average of 8 (6 to 16) months only to reveal solid bone union in all the fractures, with a mean healing time of 4.7 months (ranging from 4 to 6 months). No loosening or breakage of the implants occurred in this series. Conclusion Due to its advanced design, LISS can be used to treat effectively fracture nonunion at the distal femur and the proximal tibia.

Objective To investigate the surgical treatment and outcome of distal humeral shear fractures in adults through Kaplan approach.Methods Nine patients with closed shear fracture of the distal humerus were surgically treated through Kaplan approach from September 2005 to September 2009.The lateral collateral ligament was released only in 1 case.All the fractures were classified into type 1A (3 cases),type 1B (1 case),type 2A (1 case),type 3A (1 case) and type 3B (3 cases) according to Dubberley classification.Under the direct vision,cannulated screw was used after anatomic reduction was confirmed by fluoroscopy.Results All fractures were reduced anatomically without any neural or vascular injury.Only 1 case of grade 1 heterotopic ossification was found 12-24 months postoperatively.There were excellent in 4 cases,and good in 5 cases.The average Broberg-Morrey score was 94.2.The average arc of flexion-extension was 116°.As to the 4 cases with posterior comminution,the averaged score and the arc of flexion-extension was 92.8 and 104°,respectively.Conclusion Through Kaplan approach,the reduction and internal fixation of distal humeral shear fractures can be manipulated successfully with lateral collateral ligament intact,and the short-term outcome is satisfactory.Dubberley classification which focused on the severity and prognosis is helpful to make a surgical plan.

OBJECTIVE: To review the development and mechanism of platelet-rich plasma (PRP) and the unsolved problems so as to provide reference for the clinical application of PRP.DATA SOURCES: Articles on effects of platelet-rich plasma on bone repair are searched from Medline between January 1995 and June 2005 on computer. The key words were platelet rich plasma, bone, and repair.Meanwhile, the same search was conducted to determine the correlated articles during January 1998 to June 2005 from Wanfang database with key words of platelet-rich plasma, bone and repair in Chinese.STUDY SELECTION: Literatures at home and abroad on the PRP and bone repair were chosen; Non-randomized controlled literatures were included.DATA EXTRACTION: Totally 40 out of 49 reports related to PRP and bone repair met the criteria. 9 reports were excluded due to the repeated same research. The rest 40 reports were sorted out and conducted literature review.DATA SYNTHESIS: Platelet-rich plasma was originally used in clinic to repair mandibular defect in 1998, by adding PRP to grafts with a radiographic maturation rate 1.62 to 2.16 times that of grafts without PRP. Up to now, PRP has been used in many medical areas to accelerate tissue healing due to its advantages of safety, simple, low-cost. But some problems still remain to be studied and solved.CONCLUSION: PRP includes many sorts of growth factors and has been proved to be beneficial to the maturation of both bone tissue and soft tissues. PRP is autologous and can be produced easily and safely from autologous blood, without the concerns of transmissions and immunological rejection of various diseases.

Objective To investigate the clinical outcome of tibiotalocalcaneal arthrodesis plus retrograde intramedullary nail in treatment of severe posttraumatic tibiotalar and talocalcaneal arthritis.Methods A total of 17 cases of severe posttraumatic tibiotalar and subtalar arthritis were treated with tibiotalocalcaneal arthrodesis plus retrograde intramedullary nail between June 2003 and June 2006.Patients were evaluated by a standardized follow-up examination using ankle-hindfoot scale of the American Orthopedic Foot & Ankle Society(OFAS)score. Results Of all,14 cases were followed up postoperatively,with a mean follow-up period of 14.6 months(6-23 months).Bony fusion was achieved in 12 cases (86%)after an average of 11.6 weeks(8-19 weeks)but a delayed union in 2 after 17-19 weeks.Two cases(12%)complained heel pain at the nail entry point at initial stage of operation.The average anklehindfoot score improved from 47 points(43-55 points)preoperatively to 75 points(69-86 points)postoperatively. Conclusion Tibiotalocalcancal arthrodesis plus retrograde intramedullary nailing is proved to be effective in treating severe posttraumatic tibiotalar and talocalcaneal arthritis by marked relief from pain and improvement of life quality.