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BACKGROUND:More and more elderly patients have hip fractures because of diverse reasons, and most of the fractures are unstable fractures combined with the displacement of the lesser trochanter. At present, there are stil many reports about using dynamic hip screw to repair unstable intertrochanteric fractures, and the effect is obvious. However, there are stil great controversies regarding whether lesser trochanter fixation is performed during the repair process. OBJECTIVE:To evaluate the effect of using dynamic hip screw combined with the lesser trochanter fixation to repair intertrochanteric fractures and the occurrence of hip coxa vara after repair through a meta-analysis. METHODS:The PubMed, EMCC, CBM, CNKI, VIP and Wanfang databases were retrieved by computer for randomized controled trials on whether lesser trochanter reduction fixation was performed during the process of dynamic hip screw internal fixation for repair of intertrochanteric fractures. The quality of the included studies was evaluated according to the pre-designated inclusion and exclusion criteria. The available data were extracted and analyzed using the RevMan5.2 software. RESULTS AND CONCLUSION:A total of 10 randomized controled trials involving 604 patients were included. Among them, 298 cases were assigned to the dynamic hip screw combined with lesser trochanter fixation group, and 306 cases to the lesser trochanter unfixed group. The meta-analysis results indicated that hip coxa vara, other postoperative complications, the excelent and good rate of efficacy in the dynamic hip screw combined with lesser trochanter fixation group were al superior to those in the lesser trochanter unfixed group (alP < 0.000 1), and for hip coxa vara, the parameters were odds ratio=0.17, 95% confidence interval (0.07, 0.41),Z=3.99,P< 0.000 1. The operation time and the amount of blood loss in the lesser trochanter unfixed group were superior to those in the dynamic hip screw combined with lesser trochanter fixation group (alP < 0.000 1). These results suggest that the lesser trochanter unfixed therapy has the advantages of relatively simple operation, shorter operative time and less blood loss during the process of dynamic hip screw internal fixation for repair of unstable intertrochanteric fractures. However, the excelent and good rates of efficacy, hip coxa vara and other postoperative complications were superior in patients with intertrochanteric fracture above the Tronzo-Evans III type who received dynamic hip screw combined with lesser trochanter fixation to those who received lesser trochanter unfixed therapy. The results indicate that dynamic hip screw combined with lesser trochanter fixation for repair of intertrochanteric fracture is beneficial to prevent hip coxa vara and other complications.
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BACKGROUND: Previous studies have confirmed that in the animal models of articular cartilage defects and osteoarthritis, the chondrocytes can overexpress the matrix metal oproteinases. Various abnormal stimuli are likely to break the balance between matrix metal oproteinase and tissue inhibitor of metal oproteinase, thus leading to degeneration of extracel ular matrix of articular cartilage, as wel as the decline and offset of cartilage chondrocytes. OBJECTIVE: To observe the effect of cyclic tensile strain on the expression of matrix metal oproteinases during the repairing process of rabbit articular cartilage defects. METHODS: The animal models of articular cartilage defects were established, and chondrocytes were separated for culture at 10 weeks after operation. The chondrocytes on the non-surgical side were considered as the normal group, and the chondrocytes on the surgical side were randomly divided into high cyclic tensile strain group, low cyclic tensile strains group and control group, and the load amplitude was sin10%. Then 0.1, 1.0 and 0 Hz cyclic tensile strains were loaded respectively. The expressions of matrix metal oproteinases 2, 3, 9 and 13 in each group were detected with reverse transcription-PCR at 24, 48 hours, 1, 2 and 4 weeks after loading cyclic tensile strain. RESULTS AND CONCLUSION: There were significant differences in the expressions of matrix metal oproteinases 2, 3, 9 and 13 at 24 hours after loading cyclic tensile strain between the normal group and the control group (P < 0.05); and there were significant differences in the expressions between the high cyclic tensile strain group and the low cyclic tensile strain group at 1, 2 and 4 weeks after loading cyclic tensile strain (P < 0.05).At the same time, the expressions of matrix metal oproteinases 2, 3, 9 and 13 in the low cyclic tensile strain group were continued to decline, and there were significant differences in the expressions after loading cyclic tensile strain for 24 hours and 4 weeks (P < 0.05). The results indicate that mechanical load can affect the expression of matrix metal oproteinases in the healing process of rabbit articular cartilage defects. In the cel ular and molecular level, the incidence and development of pathological articular cartilage defect and stress should affect each other.
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Objective To observe the biocompatibility of a biomimetic designing of a multi-grade compositions in repairing articular cartilage and subchondral bone in animal bodies and repair the fullthickness defects in articular cartilage with the compositions and to study the regenerated cartilage histomorphologically. Methods Biocompatibility study: Acute general toxicity test, Haemolysis test, subcutaneous implantation test and chronic toxicity test. Articular cartilage defects repaired experimental study :The models of defects in articular cartilage were made artificially in both condylus lateralis femoris of mature rabbits. Implanted with the biomimetic designing of a multi grade compositions randomly at one side as the experimental group and the other side were untreated as the control group. The rabbits were killed at 4, 6, 8and 12 weeks after operation, respectively, with 6 ones at each time, and the macroscopic, histological, ultrastroctural examinations and semi-quantity cartilage scoring employing Wakitanifa repaired cartilage value system were performed. Results Biocompatibility study: (1) The rabbits' weight in experimental group kept growing .(2) Haemolysis rate of rats to different concentrations of diffusion solution was＜5%.(3) In chronic toxic reaction, rabbits' liver and kidney function was not different compared with the control groups at 12weeks and the index before operation. Articular cartilage defects repaired experimental study: 4-8 weeks after operation, the defects in the experimental group were partly filled with hyaline cartilage. Twelve weeks after operation, the defects in the experimental group were completely filled with mature hyaline cartilage.However, fibrous tissues were seen in the control group all the time. At 4, 6, 8, and 12 weeks postoperatively, the Wakitanifa cartilage scores were (7.60±0.98), (5.69±0.58), (4.46±0.85) and (4.35±0.12), respectively,in the experimental group and (10.25±1.05), (9.04±0.96), (8.96±0.88) and (8.88±0.68), respectively, in the control group. Differences between the control group and the experimental group were significant. Conclu sion The biomimetic designing of a multi-grade compositions has good biocompatibility and may induce cartilage regeneration to repair the full-hickness defects of articular cartilage.
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BACKGROUND: There have been many methods of fixation between lumbar-sacral spine and pelvis. However, a safe, firm, and ideal method of internal fixation has not been found.OBJECTIVE: This study was designed to investigate the stability of the fixation between lumbar-sacral spine and pelvis with the connectible skills using iliac screw and lumbar-sacral spine pedicle screw.DESIGN, TIME AND SETTING: This study, a control experiment, was performed at the Institute of Biomechanics, Sun Yat-sen University, Guangzhou, Guangdong Province, China between January 2006 and December 2007.MATERIALS: The lumbar-sacral spine and pelvis specimens were collected from six freshly cryo-preserved male adult corpses caused by trauma. Iliac screw (8.5mm×100mm), L5 pedicle screw (6.5mm×45mm), and S1 pedicle screw (6.5mm×35mm) were provided by Sofamor Company, USA. MTS 858 Bionix Material Testing System (USA) was also used.METHODS: The lumbar and iliac vertebrae, pelvis from six fresh frozen cadaveric specimens were operated in three different ways of fixation respectively: iliac ala lag screw, L5-S1 pedicle screw rod system, iliac screw and L5 pedicle screw connecting system. Three ways of fixation as mentioned above were compared with the intact group in biomechanical stability.MAIN OUTCOME MEASURES: The mobility of whirl, lateral bending, proneness, and backward stretching among groups.RESULTS: Using iliac screw for the fixation between lumbar-sacral spine and pelvis turned out to be the best in stability. The range of motion (ROM) decreased obviously in each situation. The three-dimensional mobility in the 6.4Nm moment of force was (1.07±0.86)° for whirl, (0.95±0.47)° for lateral bending, (1.22±0.67)° for proneness, and (1.80±0.73)° for backward stretching. There was significant difference between the intact group and the group carried out by iliac screw and L5 pedicle screw for the fixation between lumbar-sacral spine and pelvis (P<0.01).CONCLUSION: The connectible skills using iliac screw and the lumbar-sacral spine pedicle screw possesses the biomechanical advantages of maintaining the stability between lumbar-sacral spine and pelvis.
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BACKGROUND: Fracture is the main clinical manifestation of osteoporosis. Thus, a safe, feasible and low cost bone mineral density(BMD) measurement can help to prevent the osteoporosis-related fracture and other osteoporosis-related complications in clinical practices.OBJECTIVE: Quantitative ultrasound(QUS) measurement systems have been employed to evaluate bone status in middle-aged and aged females for better diagnoses and the prevention of osteoporosis-related fracture.DESIGN: Case controlled trial based on patients and healthy individuals.SETTING: The study was conducted at the orthopedic department of a municipal hospital.PARTICIPANTS: The study was conducted in the Orthopedic Department of the Sixth People' s Hospital of Guangzhou from February to September in 2002. Seventy-four middle-aged and aged female patients, diagnosed with fracture, entered the study procedure. A control group of 218 age-matched postmenopausal women was recruited for comparison. The patients in the control group were divided into 5 subgroups: 41 - 50 years old, 51 -60 years old; 61 - 70 years old; ＞ 80 years old. Both the patients and the healthy controls were divided into several groups according to their ages. Then each of them was measured by QUS, and the results were analyzed and compared among all the groups.MAIN OUTCOME MEASURES: The broadband ultrasound attenuation (BUA) and the speed of sound(SOS) of all the patients and the healthy women in this study.RESULTS: BUA values of over 61 years old patient groups equaled to (58.2 ± 6. 8), (54.2 ± 4.8) and(47.8 ± 3.5) dB/MHz respectively. The values were significantly different from those of the control group( P ＜ 0. 01 ).The SOS values of the over-51-year-old patient groups were( 1489.6 ± 24. 3),(1486.6 ± 17.7), (1483.7 ± 18.4) and(1442.7 ± 18.3) m/s respectively. They were also significantly different from those of the control group( P＜ 0.01).CONCLUSION: QUS measurement system not only can be used to obtain quantitative data of the bones but also can be used to evaluate the bone structure. It has various advantages such as no radiation, low cost and easiness of operation. It is a valuable method that can greatly contribute to early prediction, early diagnosis and timely treatment of osteoporosis-related fracture.
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@#ObjectiveTo assess the superiority of comprehensive therapy in the elder with osteoporotic hip fracture.Methods163 elderly patients with osteoporotic hip fracture were retrospectively analyzed,in which 50 patients accepted routine therapy only,and other 113 patients accepted routine therapy combined with anti-osteoporosis comprehensive therapy.The effect and the incidence of complications in two groups were compared. Results105 patients had been followed-up for 5—36 months. There were the high effective rate and the low complication rate in the group of comprehensive therapy(P<0.05),compared with the routine group. Conclusions Comprehensive therapy should be adopted in the elder with osteoporotic hip fracture.