Dynamic Observation on the Effects of Different Suture Techniques on the Biomechanical Properties in the Healing of Tendons

Summary： To identify the best suture techniques for the tendon repair, the biomechanical properties of tendons sutured by different methods were dynamically examined. 140 chickens were divided into 2 groups equally： group A and group B. The tendon of the right side was subjected to injury-repair process, and the tendons of the left sides served as controls in both groups. In group A, ＂figure-of- 8＂ suture, modified Kessler suture and Bunnell suture were used for the 2nd to 4th paws respectively, while in group B, Kleinert suture, Tsuge suture and Ikuta suture were used. On the day 0, 3, 7, 14, 21, 28, 42 after operation, 10 animals were sacrificed and the flexor tendons of both sides were harvested for strength test. The results showed that the initial strength of the repaired tendons and the strength after 6 weeks following tendon cut were far below those of intact tendons, irrespective of suture techniques used. With the 6 techniques, the P of tendons repaired by Tsuge suture was increased continually, reaching the highest value on the 42nd day. The P of tendons sutured by the modified Kessler suture was slightly lower than that by Tsuge suture, but it was increased steadily in healing. The tendons repaired by figure-of-8 suture yielded the lowest P It was concluded that Tsuge suture and modified Kessler suture were the best techniques for tendon repair.     

经腱缝合与双排固定修复III度关节侧肩袖部分撕裂的生物力学比较

Background For partial-thickness tears of the rotator cuff, double-row fixation and transtendon single-row fixation restore insertion site anatomy, with excellent results. We compared the biomechanical properties of double-row and transtendon single-row suture anchor techniques for repair of grade Ⅲ partial articular-sided rotator cuff tears.Methods In 10 matched pairs of fresh-frozen sheep shoulders, the infraspinatus tendon from 1 shoulder was repaired with a double-row suture anchor technique. This comprised placement of 2 medial anchors with horizontal mattress sutures at an angle of .≤45° into the medial margin of the infraspinatus footprint, just lateral to the articular surface, and 2 lateral anchors with horizontal mattress sutures. Standardized, 50% partial, articular-sided infraspinatus lesions were created in the contralateral shoulder. The infraspinatus tendon from the contralateral shoulder was repaired using two anchors with transtendon single-row mattress sutures. Each specimen underwent cyclic loading from 10 to 100 N for 50 cycles, followed by tensile testing to failure. Gap formation and strain over the footprint area were measured using a motion capture system; stiffness and failure load were determined from testing data.Results Gap formation for the transtendon single-row repair was significantly smaller （P 〈0.05） when compared with the double-row repair for the first cycle （（1.74±0.38） mm vs. （2.86±0.46） mm, respectively） and the last cycle （（3.77±0.45） mm vs. （5.89±0.61） mm, respectively）. The strain over the footprint area for the transtendon single-row repair was significantly smaller （P 〈0.05） when compared with the double-row repair. Also, it had a higher mean ultimate tensile load and stiffness.Conclusions For grade Ⅲ partial articular-sided rotator cuff tears, transtendon single-row fixation exhibited superior biomechanical properties when compared with double-row fixation.     

Biomechanical evaluation of different posterior occipitocervical fixation techniques

Objective To evaluate biomechanic stability of occipitoatlantoaxial reconstruction with different internal fixations. Methods Twelve fresh human cadaveric occipitocervical spine specimens were mounted in a spine-testing machine to record the three-dimensional angular movement at occiput OcC1 and C1,2. The specimens were tested under five different oonditions： the intact, the occipitoatlantoaxial instability, fixation with Ti-cable plus bone graft group （group A）, fixation with the transarticular screw fixation （group B）, fixation with SUMMIT occipitocervical spinal fixation system （group C）.     

Relationship between tyrosine phosphorylation and protein expression of insulin receptor and insulin resistance in gestational diabetes mellitus

Summary： The relationship between tyrosine phosphorylation （TP） and protein expression of insulin receptor （InsR） and insulin resistance （IR） in patients with gestational diabetes mellitus （GDM） was investigated. The InsR expression and TP in skeleton muscle tissue were determined by Western blotting and immunoprecipitation in women with GDM （GDM group, n=22）, normal pregnant women （normal pregnancy group, n=22） and normal non-pregnant women （normal non-pregnant group, n=13）. Fasting plasma glucose （FPG） and fasting insulin （FINS） were measured by oxidase assay and immunoradioassay. The results showed that the levels of FPG （5.61±0.78 mmol/L）, FINS （15.42±5.13 mU/L） and Ho- meostasis model assessment-IR （HOMA-IR） （1.21±0.52） in GDM group were significantly higher than those in normal pregnancy group （4.43±0.46 mmol/L, 10.56±3.07 mU/L and 0.80±0.31 respectively） （P〈0.01）. The levels of FINS and HOMA-IR in normal pregnancy group were significantly higher than those in normal non-pregnant group （7.56±2.31 mU/L and 0.47±0.26 respectively） （P〈0.01）. There was no significant difference in the InsR expression level among the three groups （P〉0.05）. TP of InsR with insulin stimulation was significantly decreased in GDM group （0.20±0.05） as compared with normal pregnancy group （0.26±0.06） （P〈0.01）. TP of InsR with insulin stimulation in normal pregnancy group was lower than that in normal non-pregnant group （0.31±0.06） （P〈0.01）. TP of InsR with insulin stimu- lation was negatively related with HOMA-IR in GDM group （r=-0.525, P〈0.01）. There was no correlation between the protein expression of InsR and HOMA-IR in GDM group （r=-0.236, P〉0.05）. It was suggested that there is no significant correlation between the protein expression of InsR in skeletal muscle and IR in GDM, but changes in TP of InsR are associated with IR in GDM.     

Mechanical tests on the reconstructed anterior cruciate ligament fixed with allogenetic cortical bone cross-pin on the femoral side

Background Anterior cruciate ligament reconstruction （ACLR） has developed dramatically in the last century.Now,ACLR has become a reliable and productive procedure.Patients feel satisfied in 〉90% cases.The aim of this study was to evaluate the feasibility of allogenetic cortical bone cross-pin （ACBCP） used as a clinical fixation method in anterior cruciate ligament reconstruction on the femoral side based on biomechanical tests in vitro.Methods The specimens were provided by the bone banks of the First Affiliated Hospital of People＇s Liberation Army of General Hospital from September 2011 to June 2012.Fresh deep frozen human allogenetic cortical bone was machined into cross-pins which is 4.0 mm in diameter and 75.0 mm in length.Biomechanical parameters compared with Rigidfix were collected while cross-pins were tested in double-shear test.The load-to-failure test and cycling test were carried out in a goat model to reconstruct anterior cruciate ligament with Achilles tendon autograft on the femoral side fixed by human 4.0 mm ACBCP and 3.3 mm Rigidfix served as control.Maximum failure load,yield load,and stiffness of fixation in single load-to-failure test were compared between the two groups.Cycle-specific stiffness and displacement at cycles 1,30,200,400,and 1 000 were also compared in between.Results In double-shear test both maximum failed load and yield load of 4.0 mm humanACBCP were （1 236.998±201.940） N.Maximum failed load and yield load of Rigidfix were （807.929±110.511） N and （592.483±58.821） N.The differences of maximum failed load and yield load were significant between ACBCP and Rigidfix,P 〈0.05.The shear strength of ACBCP and Rigidfix were （49.243±8.039） MPa and （34.637±3.439） MPa,respectively,P 〈0.05.In the load-to-failure test ex vivo,yield load and maximum failed load of ACBCP fixation complexity （（867.104±132.856）N,（1 032.243±196.281） N） were higher than those of Rigidfix （（640.935±42.836） N,（800.568±64.890） N,P 〈0.05）.However,s     

Combination of medial patellofemoral ligament reconstruction with vastus medialis advancement for chronic patellar dislocation

Background The medial patellofemoral ligament （MPFL） reconstruction is popular in clinical practice for chronic patellar dislocation; however, the combination with vastus medialis advancement is rare. The aim of this study was to evaluate the clinical outcome of the combination of MPFL reconstruction with vastus medialis advancement.Methods We retrospectively analyzed 69 patients with chronic patellar dislocation between July 2004 and October 2008： twenty eight cases with isolated MPFL reconstruction （group Ⅰ）, forty one cases with the combination of MPFL reconstruction with vastus medialis advancement （group C）. All patients had CT scans available for review with knee flexion at 30 degree, on which the congruence angle, patellar tilt angle and patellar lateral shift were measured. Physical apprehension tests were examined and the redislocation was recorded. In addition, knee function was evaluated using the Kujala score and subjective questionnaires.Results Patients were followed up for a mean of 42 months （12-65 months） without a recurrent dislocation reported.Postoperatively, all indexes on CT scan were within the normal range without a statistical difference between the two groups. Results from the apprehension test showed eight patients in group Ⅰ and three in group Chad patellar lateral shift exceeding 1.5 cm with a hard end point （P 〈0.05）. The Kujala score improved significantly from 51.3±4.5 to 79.9±6.2 in group Ⅰ and from 53.7±5.2 to 83.9±6.5 in group C （P 〉0.05）. However, the subjective questionnaire revealed a significant difference （P 〈0.05）, including 12 excellent, seven good and nine fair in group Ⅰ and 30 excellent, six good and five fair in group C.Conclusion The combination of MPFL reconstruction with vastus medialis advancement is better than isolated reconstruction to improve the subjective effects and decrease the patellar instability rate for chronic patellar dislocation.     

Effect of two volume responsiveness evaluation methods on fluid resuscitation and prognosis in septic shock patients

Background Few studies have reported the effect of different volume responsiveness evaluation methods on volume therapy results and prognosis.This study was carried out to investigate the effect of two volume responsiveness evaluation methods,stroke volume variation （SW） and stroke volume changes before and after passive leg raising （PLR-ASV）,on fluid resuscitation and prognosis in septic shock patients.Methods Septic shock patients admitted to the Department of Critical Care Medicine of Zhejiang Hospital,China,from March 2011 to March 2013,who were under controlled ventilation and without arrhythmia,were studied.Patients were randomly assigned to the SVV group or the PLR-ASV group.The SVV group used the Pulse Indication Continuous Cardiac Output monitoring of SW,and responsiveness was defined as SW-＞12％.The PLR-ASV group used ASV before and after PLR as the indicator,and responsiveness was defined as ASV ＞15％.Six hours after fluid resuscitation,changes in tissue perfusion indicators （lactate,lactate clearance rate,central venous oxygen saturation （SCVO2）,base excess （BE））,organ function indicators （white blood cell count,neutrophil percentage,platelet count,total protein,albumin,alanine aminotransferase,total and direct bilirubin,blood urea nitrogen,serum creatinine,serum creatine kinase,oxygenation index）,fluid balance （6-and 24-hour fluid input） and the use of cardiotonic drugs （dobutamine）,prognostic indicators （the time and rate of achieving early goal-directed therapy （EGDT） standards,duration of mechanical ventilation and intensive care unit stay,and 28-day mortality） were observed.Results Six hours after fluid resuscitation,there were no significant differences in temperature,heart rate,blood pressure,SpO2,organ function indicators,or tissue perfusion indicators between the two groups （P ＞0.06）.The 6-and 24-hour fluid input was slightly less in the SW group than in the PLR-ASV group,but the difference was not statistically significant （P ＞0.05）.The SW group used significantly more dobutamine than the PLR-ASV group （33.3％ vs.10.7％,P =0.039）.There were no significant differences in the time （（4.8±1.4） h vs.（4.3±1.3） h,P=0.142） and rate of achieving EGDT standards （90.0％ vs.92.9％,P =0.698）,or in the length of mechanical ventilation and ICU stay.The 28-day mortality in the SW group （16.7％ （5/30）） was slightly higher than the PLR-ASV group （14.3％ （4/28））,but the difference was not statistically significant （P =0.788）.Conclusions In septic shock patients under controlled ventilation and without arrhythmia,using SW or PLR-ASV methods to evaluate volume responsiveness has a similar effect on volume therapy results and prognosis.The evaluation and dynamic monitoring of volume responsiveness is more important for fluid resuscitation than the evaluation methods themselves.Choosing different methods to evaluate volume responsiveness has no significant influence on the effect of volume therapy and prognosis.     

Locking plate fixation combined with iliac crest bone autologous graft for proximal humerus comminuted fracture

Background Although the use of an intramedullary fibular allograft together with locking plate fixation can provide additional medial support and prevent varus malalignment in displaced proximal humeral fractures with promising results,the fibular autograft donor site often sustains significant trauma and cannot restore the articular surface of comminuted fractures.The aim of this study was to evaluate the clinical and radiographic outcomes of a locking plate and crest bone autologous graft for treating proximal humerus comminuted fractures.Methods We assessed the functional outcomes and complication rates in 40 patients with proximal humerus comminuted fractures.Eighteen patients were treated with a locking plate and an autologous crest bone graft （experimental group）,and 22 were treated with only the locking plate and no bone graft （control group）.Postoperative assessments included radiographic imaging,range of motion analysis,pain level based on the visual analogue scale （VAS）,and the SF-36 （Short Form （36） Health Survey）,as well as whether patients could retum to their previous occupation.Results All fractures healed both clinically and radiologically in the experimental group.There was no more than 2 mm collapse of the humeral head,and no osteonecrosis or screw penetration of the articular surface.In contrast,two patients had a nonunion in the control group,and they eventually accepted total shoulder replacements.The average time from surgery to radiographic union was significantly shorter in the experimental group （（4.66±1.63） months） compared with the control group （（5.98±1.57） months） （P ＜0.05）.For the experimental versus controls groups,the mean shoulder active flexion （148.00±18.59 vs.121.73±17.20） degrees,extension （49.00±2.22 vs.42.06±2.06） degrees,internal rotation （45.00±5.61 vs.35.00±3.55）degrees,external rotation （64.00±9.17 vs.52.14±5.73）degrees,and abduction （138.00±28.78 vs.105.95±15.66） degrees were all significantly higher （all P ＜0.001）.The median SF-36 in the experimental group （（88.00±5.71） points） was significantly higher than that of the control group （（69.45±9.45） points; P ＜0.001）.The median VAS pain level （mean rank,10.50） in the experimental group was lower than that （mean rank,47.19） of the control group （P ＜0.001）.All but one patient （17 of 18,94.4％） in the experimental group returned to their previous activities or occupations,and that one patient changed to a different occupation because of slight restrictions to activities.On the other hand,four patients could not return to their previous activities or occupations in the control group.Conclusion Locking plate fixation combined with an iliac crest bone graft is an effective technique for treating proximal humerus comminuted fractures.     

A novel method of defective vascular reconstruction using 2-octyl-cyanoacrylate and homemade prosthetic component

Background Currently,adhesive technique is popular in vascular repair but not widely used for defective vessels.This study aimed to determine the feasibility and effectiveness of repairing defective vessels with 2-octyl-cyanoacrylate and a homemade prosthetic component.Methods Homemade prosthetic component consisting of expanded polytetrofluoroethylene （ePTFE）,terylene film,and homemade soluble hollow stent mixed with adhesive can replace autologous graft and suture in repairing defective vessels,can fix vessels better using the stent without occlusive bleeding.Forty male mongrel dogs were used,20 for biomechanical tests and 20 for animal experiments.In the biomechanical test,dogs were randomly divided into two groups （n=10 each）,one group repaired on the two sides of the carotid arteries with 2-octyl-cyanoacrylate and homemade component and another group repaired with suture and ePTFE.Of the 40 specimens,10 were used for adhesive and 10 for suture specimens for tension strength test,whereas the remaining specimens were used for bursting pressure test.In animal experiments,dogs were also divided into adhesive and suture groups （n=10）,only of the left carotid artery.Recording the operational time,bleeding or not.Vessels were tested using color Doppler ultrasound,the inner diameter was measured,and the degree of stenosis at 8 weeks was evaluated digital subtraction angiography （DSA） were also performed.Specimens were then analyzed histologically.Results In the adhesive and suture groups,the specimens could afford atension strength of （23.80±1.51） N versus （24.60±1.08） N （P ＞0.05）,the bursting pressure was （52.03±.2.43） kPa versus （50.04±3.51） kPa （P ＞0.05）,and the mean time of anastomosis was （15.20±0.55） minutes versus （25.97±0.58） minutes （P ＜0.05）.One dog in the adhesive group was bleeding from the suture.One dog from each group presented with thrombosis at 1 week.After measuring using ultrasound,the stenosis degree of all dogs were no more than 30％ except the two thromboses.DSA and histological observation showed no obvious difference between the two groups.Conclusion Defective vascular anastomosis with 2-octyl-cyanoacrylate and our homemade prosthetic component is feasible,effective,timesaving,and easy to master.     

Antithrombin-III without concomitant heparin improves endotoxin-induced acute lung injury rats by inhibiting the activation of mitogen-activated protein kinase

Background Antithrombin-Ⅲ （AT-Ⅲ）, the major inhibitor of thrombin in plasma, also has anti-inflammation property and might have positive effect on sepsis. The present study aimed to investigate the effects of AT-Ⅲ on inflammatory reaction and pulmonary protection in endotoxin-induced acute lung injury （ALI） rat. Methods Sixty male Sprague-Dawley rats were randomly assigned equally to normal control group, ALl group, AT-Ⅲ treatment group, AT-Ⅲ＋heparin treatment group, and heparin treatment group. The pulmonary vascular permeability index （PVPI） was measured by single nuclide tracer technique. The activity of AT-Ⅲ in plasma was determined by the method of synthetic chromogenic substrata. Tumor necrosis factor-a （TNF-a） and interleukin-6 （IL-6） levels in serum were determined by enzyme-linked immunosorbent assay. The expressions of lung tissue mitogen-activated protein kinases （ERK1/2, P38 and JNK MAPK） were determined by Western blotting. Results Rats had significantly improved lung histopathology in the AT-Ⅲ treatment group and heparin treatment group compared with the ALl group, The PVPI of the ALl group was 0.38±0.04, significantly higher than that of the normal control group （0.20±0.02, P 〈0.01）, AT-Ⅲ treatment group （0.30±0.04, P 〈0.01） and heparin treatment group （0.28±0.04, P 〈0.01） respectively. There were no significant differences of PVPI in the ALl group and AT-Ⅲ＋heparin treatment group. The activity of AT-Ⅲ in plasma in the ALl group was （76±8）%, significantly lower than that of the normal control group （（96±11）%, P 〈0.05） and AT-Ⅲ treatment group （（105±17）%, P 〈0.05） respectively. The serum levels of TNF-α and I L-6 of the ALl group were （2.770±0.373） μg/L and （1.615±0.128） ng/ml respectively, significantly higher than those of the normal control group （0.506±0.093） μg/L and （0.233±0.047） ng/ml respectively, all P 〈0.01）, AT-Ⅲ treatment group （（1.774±0.218） pg/L and （1.140±0145） ng/ml respectively, all P 〈0.01） and heparin treatment group （（1.924±0.349） μg/L and （1.223±0.127） ng/ml respectively, all P 〈0.01）. The lung tissue levels of phospho-ERK1/2 and phospho-P38 MAPK expressions were markedly higher in the ALl group than in the normal control group, AT-Ⅲ treatment group and heparin treatment group respectively. Conclusions AT-Ⅲ without concomitant heparin inhibited the activation of ERK1/2 and P38 MAPK, down-regulated the levels of downstream cytokines TNF-a and IL-6, relieved endothelial permeability, and improved the ALl in endotoxin-induced rats. It might be helpful to administrate AT-Ⅲ alone, not with concomitant heparin, to those patients with ALl and sepsis.     

腘绳肌腱移植重建内侧髌骨韧带的生物力学研究

目的：探讨正常内侧髌骨韧带（MPFL）的抗拉强度和自体肌腱移植重建MPFL的生物力学特性。方法：采用新鲜冰冻尸体膝关节标本解剖出MPFL,测定其侧抗拉强度。腘绳肌腱移植模拟MPFL重建术,采用肌腱移植髌骨缝合固定法和锚钉固定法,测定重建后的抗拉强度。结果：缝合固定法的强度高于正常MPFL强度及锚钉固定法的固定强度,其差异有统计学意义（P〈0.05）。结论：肌腱移植髌骨缝合固定法重建MPFL其抗拉强度完全可以满足临床需求,与锚钉固定法相比无异物存留,更加经济、简便和有效。     

自体腘绳肌腱移植治疗复发性髌骨脱位

目的比较不同固定方法自体腘绳肌腱移植重建内侧髌骨韧带（MPFL）,治疗复发性髌骨脱位的临床疗效。方法本研究共入选15例（17膝）复发性髌骨脱位的患者,其中女性13例（15膝）,男性2例（2膝）。平均年龄25．7岁（15～44岁）。入选病例随机分为两组：Ⅰ组为U形隧道法重建MPFL,Ⅱ组为髌骨内缘缝合固定法重建MPFL。术中根据不同软骨损伤情况行刨削刀打磨及射频汽化修整损伤软骨,髌股外侧支持带松解后采用自体腘绳肌腱移植重建内侧髌骨支持带。关节镜下动态调整移植肌腱在膝关节不同屈伸角度下的张力及运动轨迹,位置满意后髌骨端分别采用U形隧道法（8例10膝）或缝合法（7例7膝）固定;股骨端均采用界面螺钉固定。术前及术后随访时记录Kujala评分及Lysholm评分。结果所有患者术后均获随访,平均34．8个月（8—60个月）。术后Kujala评分U形法平均（73．7±7．04）分,缝合法平均（86．7±7．70）分;Lysholm评分U形法平均（69．0±12．1）分,缝合法平均（80．4±14．3）分。随访期U形法固定组1例发生髌骨下极骨折,1例发生再脱位,骨折经手术治疗后膝关节功能恢复良好。结论关节镜下外侧髌股支持带松解与腘绳肌腱移植重建内侧髌股韧带治疗复发性髌骨脱位疗效可靠,缝合固定法创伤小,操作简便,费用低廉,易于推广。     

Isometric behavior of the reconstructed medial patellofemoral ligament using two different femoral pulleys: a cadaveric study.

BACKGROUND: Several techniques have been described for reconstructing the medial patellofemoral ligament (MPFL). However, the anatomy of the medial patellar retinaculum and the isometry of both intact and reconstructed MPFL remain controversial. The purpose of this study was to investigate the isometric behavior of the reconstructed MPFL when two different pulleys are used for the reconstruction. MATERIAL/METHODS: Eight anatomical knees were dissected and the medial patellar retinaculum and MPFL were studied. A pilot technique for the reconstruction of the MPFL using a semitendinosus autograft was developed. A "dynamic" femoral fixation was chosen which utilized two different pulleys: the medial intermuscular septum (MIS) at the adductor's tendon insertion and the posterior third of the medial collateral ligament (MCL). The isometric behavior of the reconstructed MPFL and the stability of both pulleys were investigated. RESULTS: The MPFL was a thickened, band-like condensation of the superficial MPR layer extending from the MFE to the medial border of the patella. The reconstructed MPFL demonstrated the most isometric behavior when the MCL was used as a pulley. The average difference in graft length during knee flexion from 0 degrees to 90 degrees when the MCL or MIS were used as a pulley was 1 mm and 4 mm, respectively. The MIS pulley was more stable but less isometric than the MCL pulley. CONCLUSIONS: "Dynamic" MPFL reconstruction with a semitendinosus tendon autograft can restore patellofemoral stability without excessive soft-tissue dissection or implantation of hardware at the medial epicondyle, which can lead to symptoms of its own.     

岗上肌肌腱不同修补方法的实验研究

目的研究缝合锚单纯间断缝合法、缝合锚褥式缝合法和Mclaughlin缝合法修补兔岗上肌肌腱损伤的效果。方法选用45只新西兰兔,将其随机分为3组,每组15只。兔的左侧岗上肌肌腱自止点处切断,宽度8mm,建立岗上肌肌腱损伤模型,右侧岗上肌肌腱作为对照。A组采用缝合锚单纯间断缝合法缝合损伤的岗上肌肌腱;B组采用缝合锚褥式缝合法缝合;C组采用传统的Mclaughlin缝合法缝合。观察岗上肌肌腱的愈合情况,比较各组动物的愈合率。每组随机抽取12只动物取其双侧肩胛带标本进行生物力学测试,测定岗上肌肌腱的愈合强度。其余动物取其左侧肩胛带标本硝酸脱钙后HE染色进行组织学观察,观察岗上肌肌腱止点处的愈合情况。结果A、B两组各有1只动物因感染导致修补失败,愈合率为93．33％;C组动物全部愈合,愈合率为100％,3组动物愈合率进行x^2检验,x^2=1．047,其差异没有统计学意义（P〉0．05）。A组岗上肌肌腱愈合后抗拉力最大负荷的平均值为（82．4±20．7）N;B组抗拉力最大负荷平均值为（81．8±20．3）N;C组抗拉力最大负荷平均值为（88．6±17．2）N。采用方差分析的方法进行统计学处理F=0．446,3组之间的差异没有统计学意义（P〉0．05）。组织学研究表明A、B两组肌腱止点处为岗上肌肌腱直接附着于板层骨,C组肌腱止点处为岗上肌肌腱、软骨、板层骨相互移行的结构,但与正常的肌腱止点处相比软骨细胞的数量明显减少。结论缝合锚单纯间断缝合法、缝合锚褥式缝合法与Mclaughlin缝合法对兔岗上肌肌腱修补在愈合率和愈合强度上统计学无明显差别,但Mclaughlin缝合法愈合后强度略大于前两者,组织学上的愈合情况更接近正常肌腱的止点结构。     

关节镜辅助下内侧髌股韧带重建治疗复发性髌骨脱位

目的探讨关节镜辅助下内侧髌股韧带(MPFL)重建治疗复发性髌骨脱位的方法和临床疗效。方法将2008年7月至2010年9月该院收治的复发性髌骨脱位13例患者,全部采用关节镜辅助下自体半腱肌腱移植重建MPFL,术前、术后1年按照Lysholm评分评价膝关节功能。结果所有患者均获随访,随访时间1.1～3.2年,平均1.7年,均无髌骨再脱位发生及关节活动度受限。Lysholm评分术前平均为(73.5±4.7)分,术后1年平均为(94.7±4.5)分,移植前、后Lysholm评分比较差异有统计学意义(P<0.01)。结论采用关节镜辅助下MPFL重建,操作简单、微创、髌骨稳定性好,是治疗复发性髌骨脱位的有效方法。     

Biomechanical evaluation of flexor tendon repair techniques

Biomechanical evaluation of flexor tendon repair techniques@Wang B @Chen F @Pan CZ @Xie RG     

Intrafix与界面螺钉在前交叉韧带重建中的生物力学研究

目的 探讨胭绳肌腱移植重建前交叉韧带(ACL)胫骨端界面螺钉与Intrafix固定的生物力学.方法 新鲜冰冻尸体膝关节标本14具,采用四股腘绳肌腱移植重建ACL,胫骨端分别采用可吸收界面螺钉(n=7)和Intrafix(n=7)固定,测试最大载荷、100 kg·m·s-2和400 kg·m·s-2位移、抗拉刚度、失败模式等数据并进行统计学分析.结果 Intrafix固定组的最大载荷大于可吸收界面螺钉组,两组间差异有统计学意义(t=0.003,P<0.05);100 kg·m·s-2位移和400 kg·m·s-2位移两组间差异无统计学意义(t=0.2173、0.0944,P>0.05),抗拉刚度两组间差异无统计学意义(t=0.0967,P>0.05).结论 四股胭绳肌腱移植重建ACL,胫骨端采用可吸收界面螺钉和Intrafix固定均可满足ACL初期固定强度的需求;Intrafix固定强度大于可吸收界面螺钉.     

Biomechanical comparison of double-row versus transtendon single-row suture anchor technique for repair of the grade Ⅲ partial articular-sided rotator cuff tears

Background For partial-thickness tears of the rotator cuff, double-row fixation and transtendon single-row fixation restore insertion site anatomy, with excellent results. We compared the biomechanical properties of double-row and transtendon single-row suture anchor techniques for repair of grade Ⅲ partial articular-sided rotator cuff tears.Methods In 10 matched pairs of fresh-frozen sheep shoulders, the infraspinatus tendon from 1 shoulder was repaired with a double-row suture anchor technique. This comprised placement of 2 medial anchors with horizontal mattress sutures at an angle of .≤45° into the medial margin of the infraspinatus footprint, just lateral to the articular surface, and 2 lateral anchors with horizontal mattress sutures. Standardized, 50% partial, articular-sided infraspinatus lesions were created in the contralateral shoulder. The infraspinatus tendon from the contralateral shoulder was repaired using two anchors with transtendon single-row mattress sutures. Each specimen underwent cyclic loading from 10 to 100 N for 50 cycles, followed by tensile testing to failure. Gap formation and strain over the footprint area were measured using a motion capture system; stiffness and failure load were determined from testing data.Results Gap formation for the transtendon single-row repair was significantly smaller (P ＜0.05) when compared with the double-row repair for the first cycle ((1.74±0.38) mm vs. (2.86±0.46) mm, respectively) and the last cycle ((3.77±0.45) mm vs. (5.89±0.61) mm, respectively). The strain over the footprint area for the transtendon single-row repair was significantly smaller (P ＜0.05) when compared with the double-row repair. Also, it had a higher mean ultimate tensile load and stiffness.Conclusions For grade Ⅲ partial articular-sided rotator cuff tears, transtendon single-row fixation exhibited superior biomechanical properties when compared with double-row fixation.     

皮质骨嵌压钉在前交叉韧带重建中的生物力学研究

目的探讨胭绳肌腱移植重建前交叉韧带（ACL）胫骨端皮质骨嵌压钉的生物力学。方法新鲜冷冻膝关节标本21具（北京市解剖学会提供）,采用四股胭绳肌腱移植重建ACL,胫骨端分别用自制皮质骨嵌压钉（n=7）、可吸收界面螺钉（n=7）和Intrafix（n=7）固定,测试最大载荷、100N和400N位移、抗拉刚度、失败模式等数据并进行统计学分析。结果以上指标在皮质骨嵌压钉组和可吸收界面螺钉组无统计学差异。皮质骨嵌压钉组的最大拔出载荷及抗拉刚度〈Intrafix固定组（P〈0．05）,100N位移、400N位移〉Intrafix固定组（P〈0．05）。结论自制皮质骨嵌压钉的最大拔出载荷、100N位移、400N位移以及抗拉刚度均与可吸收界面螺钉相近,可以满足ACL重建固定肌腱的需要。     

自体腓骨长肌腱前1/2双束解剖重建内侧髌股韧带联合外侧支持带松解治疗复发性髌骨脱位12例报告及文献复习

目的：观察自体腓骨长肌腱前1/2双束解剖重建内侧髌股韧带（MPFL）联合外侧支持带松解治疗12例复发性髌骨脱位的手术过程和疗效,探讨复发性髌骨脱位的病因及治疗方法。方法：收集12例复发性髌骨脱位患者,取自体腓骨长肌腱前1/2双束解剖重建MPFL,髌骨侧使用2枚带线锚钉固定于其解剖止点,2枚锚钉间距约1cm,股骨侧以1枚界面螺钉挤压固定,同时行膝关节外侧支持带松解。观察患者手术前后膝关节Lysholm评分、IKDC评分、髌骨适合角、J型征、髌骨研磨试验和髌骨恐惧试验情况。结果：所有患者平均随访16.4个月,术前膝关节Lysholm评分低于末次随访（t=9.03,P < 0.01）;术前IKDC评分低于末次随访（t=9.75,P < 0.01）;术前髌骨适合角大于术后（t=7.22,P < 0.01）;术前患者J型征、髌骨研磨试验和髌骨恐惧试验（+）,术后患者J型征、髌骨研磨试验和髌骨恐惧试验（-）。患者术后均未发生髌骨骨折及再次脱位。结论：取自体腓骨长肌腱前1/2双束解剖重建MPFL联合外侧支持带松解术治疗复发性髌骨脱位疗效好,适合临床推广。