Objective To investigate the influence of collagen on the biomechanics strength of tissue engineering tendon. Methods All of 75 nude mice were madethe defect models of calcaneous tendons, and were divided into 5 groups randomly. Five different materials including human hair, carbon fibre (CF), polyglycolic acid (PGA), human hair and PGA, and CF and PGA with exogenous collagen were cocultured with exogenous tenocytes to construct the tissue engineering tendons.These tendons were implanted to repair defect of calcaneous tendons of right hind limb in nude mice as experimental groups, while the materials without collagenwere implanted to repair the contralateral calcaneous tendons as control groups. In the 2nd, 4th, 6th, 8th and 12th weeks after implantation, the biomechanicalcharacteristics of the tissue engineering tendon was measured, meanwhile, the changes of the biomechanics strength were observed and compared. Results From the 2nd week to the 4th week after implantation, the experimental groups were ber than the control groups in biomechanics, there was statistically significantdifference (Plt;0.05). From the 6th to 12th weeks, there was no statisticallysignificant difference between the experiment and control groups (Pgt;0.05). Positivecorrelation existed between time and intensity, there was statistically significant difference (Plt;0.05). The strength of materials was good in human hair,followed by CF, and PGA was poor. Conclusion Exogenous collagen can enhance the mechanics strength of tissue engineering tendon, and is of a certain effect on affected limb rehabilitation in early repair stages.
Objective To investigate the influence of the exogenouscollagen on the function of cells in construction of artificial biotendon.Methods Three materials including human hair, carbon fiber(CF) and polyglycolic acid (PGA) were combined with exogenous collagen and co-cultured with standard transferred human embryonic tenocytes at a concentration of 3×106/mm3 in vitro. The cell number and morphology were observed under inverted microscope and scanning electron microscope after 2 hours, 3 days and 5 days.Results In the artificial biotendon combined with collagen, the cells concentrated around the materials and the cells adhering to the materials turned into round after 2 hours. After 3 days, the adhering cells increased. After 5 days, the shape of the cells changed from round to spindle.ConclusionExogenous collagen will facilitate the cells to adhere onto materials and proliferate.
ObjectiveTo summarize the progress in treatment of pubic symphysis diastasis. MethodsRelated literature concerning treatment of pubic symphysis diastasis was extensively reviewed and comprehensively analyzed in terms of anatomy, biomechanics, and treatment. ResultsThere are many fixation methods for treatment of pubic symphysis diastasis, which aims at restoring the stability of the anterior pelvic ring. External fixator is often used as a temporary fixation; tension band wire has been abandoned due to its poor biomechanical stability; screw loosening and plate breakage often appears when a single reconstruction plate is used; box plate significantly increases the biomechanical stability of anterior pelvic ring but it leads to a considerable surgical trauma; locking plate has been used for pubic symphysis diastasis recently, especially for osteoporotic fractures; percutaneous cannulated screw has the advantages of less trauma, less bleeding, and good stability, so it is good choice for treatment of pubic symphysis diastasis. ConclusionThere is no uniform standards about the treatment of pubic symphysis diastasis, but the minimally invasive treatment is an undeniable trend. Percutaneous cannulated screw has achieved satisfactory effectiveness, however, its biomechanical stability and anatomic channels need to be further studied.
目的:总结髋臼骨折的手术入路和复位固定经验。方法:2006年1月至2008年2月经Kocher Langenbeck、髂腹股沟、前后联合入路手术治疗髋臼骨折52例。结果:随访6～36个月,优良率90.4％。术后发生创伤性关节炎10例,股骨头坏死2例,异位骨化10例,所有患者均骨愈合。结论:手术治疗髋臼骨折能较好地恢复骨盆形态及下肢活动功能,防止骨折畸形愈合。正确的选择手术入路和术中良好的复位固定是提高髋臼骨折疗效的基础。
ObjectiveTo evaluate the clinical therapeutic effect of support plates on Schatzker type Ⅳ tibial plateau fractures.MethodsPatients with Schatzker type Ⅳ tibial plateau fractures underwent support plates treatment between April 2013 and September 2014 by using the medial incision or posterior medial incision, if necessary, with other auxiliary incisions, with limited contact compression plate, 1/3 tubular plate or " T” plate to support the fracture. ResultsA total of 14 patients including 6 males and 8 females with an average age of (35.2±9.8) years (ranged from 20 to 52 years) were enrolled in this study and followed up for 12–25 months with an average of (16.3±4.0) months. The knee joints were flexed 80–130° with an average of (97.9±13.1)° one month after the surgery and 90–140° with an average of (119.3±12.1)° three months after the surgery. One year postoperatively, the mean Hospital of Special Surgery knee score ranged from 78 to 96 with an average of 88.4±4.9. Last follow-up assessment of knee function according to Rasmussen scoring system showed excellent in 8 cases, good in 4 cases, and fair in 2 cases; the excellent and good rate was 85.7%. No postoperative complications such as infection, nonunion, vascular nerve injury, or internal fixation failure occurred. ConclusionThe support plates for the treatment of Schatzker type Ⅳ tibial plateau fractures can maintain good reduction, prevent the secondary collapse of the tibial plateau, ensure that knee joint has good alignment, less complications with vascular or nerve injuries, and finally get a satisfied function recovery.
Objective To observe the inhibitory characteristics of silver nanoparticles (AgNP) on bacterial biofilms and investigate their inhibitory effect on biofilm formation on three common orthopedic biomaterials. Methods The minimal inhibitory concentration (MIC) and minimal biofilm inhibitory concentration (MBIC) of AgNP were determined by microplate dilution assay. Biofilms of Staphylococcus aureus (ATCC 25923) were cultured on three orthopedic biomaterials (titanium alloy, titanium oxide, and stainless steel) and intervened with AgNP at concentrations of 32, 16, 8, 4, 2 and 0 μg/mL to determine the MBICs on the three materials. The effects of AgNP on biofilm formation were analyzed by scanning electron microscopy and measuring optical density. Results The MIC and MBIC of AgNP in the microplate assay were both 16 µg/mL. The MBICs of AgNP on biofilm formation in titanium oxide, titanium alloy, and stainless steel were 16 μg/mL, 32 μg/mL, and 32 μg/mL, respectively. Among the three materials, the lowest optical density was observed on titanium oxide, while the highest was on titanium alloy. Conclusions AgNP has strong antibacterial biofilm characteristics and can prevent the formation of Staphylococcus aureus biofilm in vitro. Biofilm formation is most pronounced on titanium alloy, least on titanium oxide, and intermediate on stainless steel.
Objective To evaluate the surgical treatment and its results of complex tibial plateau fractures.Methods From May 2003 to November 2004, 24 cases of complex tibial plateau fractures were treated by two-incision approaches. There were 16 males(including 1 case of bilateral), and8 females, with mean age of 40.6 years(21-65 years), eleven fractures occurred in left extremity and 14 in the right. No patients suffered open fractures. Fracture was caused by fall from height in 10 cases, by traffic accident in 12 cases and by another causes in 2 cases. According to Schatzkerclassification, type Ⅴ fracture was found in 14 extremities，type Ⅵ in 11 extremities. All cases were operated with twoincision approaches and double-plates fixation. The operation was performed 6-15 days after injury with mean 10.4 days. Results All cases were followed up from 12 to 23 months (mean 15.6 months). Time of the bone healing was 69 months, with mean 7.4 months. No reduction of anatomy was achieved because of comminuted fractures of articular surfaces in 2 limbs. The line of the lower extremity did not recover because of metaphysis comminution in 1 limb, which led to knee varus. Epidermal necrolysis was observed in 3 limbs, and the wound healedafter change dressing. The function of the knee wasevaluated according to Rasmussen’s criteria, the results were excellent in 10limbs, good in 8 limbs, fair in 3 limbs, and poor in 4 limbs. Conclusion The twoincision approaches reduced the complication of softtissueinjury, which is conductive to reduction of articular surface. Double-plates provide a sufficient internal fixation. It can permit early motion of knee joint. Therefore, two-incision approach are an effective surgical approach of treatment of complex tibial plateau fractures.
ObjectiveTo design the channels of parallel screws and cross screws for fixation of symphysis pubis diastasis through a small sample anatomic study on pubic symphysis and its neighbor structures so as to provide anatomical basis for minimally invasive fixation of symphysis pubis diastasis. MethodsEight cadaveric pelvic specimens (6 men and 2 women) were transected along L5 and the proximal 1/3 of bilateral thighs, with intact lumbar spines. The spermatic cord, womb round ligament, and corona mortis were dissected; the distance to the ipsilateral pubic tubercle was measured and subsequently the distance between pubic tubercles, the height of pubic symphysis, the diameter of outer edge of pubic tubercle, the thickness of pubic symphysis and 2 cm outside the pubic symphysis (upper, central, and lower 1/3 thickness of pubic symphysis) were measured to provide anatomical basis for the design of channels of parallel screws and cross screws. ResultsParallel screw fixation: the entry point of first screw was on the outer edge of pubic tubercle, and its exit point was on the outer edge of contralateral pubic tubercle; a cannulated screw with a diameter of 4.5 mm or 6.5 mm can be suitable for this channel. The entry point of second screw was 20 mm outside the pubic symphysis and 23 mm beneath the pubic symphysis, and its exit point was symmetrical with entry point; a cannulated screw with a diameter of 4.5 mm can be appropriate for the second channel. The direction of two screws was perpendicular to the pubic symphysis. Cross screw fixation: the entry point of cross screws was on one side of the pubic tubercle, and its exit point was 20 mm outside the contralateral pubic symphysis and 23 mm beneath the contralateral pubic symphysis; two cannulated screws with a diameter of 4.5 mm can be chosen for cross screws channels. The direction of two cross screws was intersected with the horizontal line of two pubic tubercles at an angle of 25° respectively; besides, two cross screws formed an anteversion angle and retroversion angle of 5-10° with pubic body plane, respectively. ConclusionThe channels of parallel screws and cross screws are feasible for fixation of symphysis pubis diastasis by analyzing the anatomical data of the pubic symphysis and its neighbor structures, but further biomechanical research is need to confirm the stability of two fixation methods.
Bacterial biofilms are associated with at least 80% of human bacterial infections. The clinical treatment of biofilm infection is still arduous, and therefore many new treatment options are under study, such as probiotics and their derivatives, quorum sensing inhibitors, antimicrobial peptides, phage therapy, organic acids, light therapy, and plant extracts. However, most of these schemes are not mature, and it is important to develop new research directions of anti-biofilms.
ObjectiveTo review the research progress of the application of internal fixation (INFIX) in the treatment of pelvic anterior ring injuries.MethodsThe recent literature about INFIX in the treatment of pelvic anterior ring injury concerning the surgery technique, biomechanical characteristics, indications, contraindications, advantages, complications, and effectiveness was extensively consulted, reviewed, and summarized.ResultsINFIX is a relatively novel technique for the treatment of pelvic anterior ring injuries at present. The advantages include good biomechanical properties, extensive indications, minimally invasion, convenient nursing, less complications, and excellent effectiveness.ConclusionIt is a clinical method with obvious advantages and development potential for treatment of pelvic anterior ring injuries using INFIX, and further study is needed to improve its effectiveness.