Endobutton-Intrafix与Rigidfix-Intrafix固定自体腘肌腱重建前交叉韧带的临床对照研究

[目的]分析采用Endobutton Intrafix系统与Rigidfix Intrafix系统两种固定方法固定自体腘绳肌腱重建膝前交叉韧带的临床疗效分析,探讨悬挂固定与横穿固定临床应用的适应证选择及临床效果的差异。[方法]回顾分析2011年7月~2013年4月本院骨科收治的膝前交叉韧带断裂患者共56例,Endobutton Intrafix固定组31例,Rigidfix Intrafix固定组25例。受伤后至接受重建手术时间1~36个月,平均13个月。所有患者要求术前及术后3、6、12月个来门诊随访,随访采用功能评分及影像学检查方式。功能评分采用Lysholm评分及IKDC2000评分。影像学检查主要采用术后1周膝关节正侧位X线片,术后3、6、12个月行MR检查,分别测量股骨及胫骨骨道各两处骨道长度(股骨内口、股骨中央、胫骨内口、胫骨中央)。两组股骨胫骨骨道增宽进行比较。[结果]临床随访中术后获得完整随访资料的病例共48例,其中Endobutton-Intrafix固定组26例,Rigidfix-Intrafix固定组22例,术后3、6个月两组股骨端骨道增宽差异有统计学意义(P0.05),胫骨端差异无统计学意义(P0.05)。术后12个月两组股骨端及胫骨端差异无统计学意义(P0.05)。术后3、6、12个月时行IKDC2000膝关节主观评分、Lysholm膝关节评分,比较结果。两组术前、术后评分差异均有统计学意义,但术后两组之间评分差异无统计学意义。[结论]不同的固定股骨端方式在早期(术后6个月内)骨隧道的扩大方面差异有统计学意义,但是骨道的扩大与膝关节功能评分无相关性。采用Endobuton-Intrafix与Rigidfix-Intrafix两种方法都可以保证在膝前交叉韧带重建中坚强固定移植物,在早期康复锻炼恢复膝关节的功能方面无明显差异。     

前交叉韧带重建术后骨道增宽的临床研究

目的分析前交叉韧带（ACL）重建术后骨道增宽的发生率、增宽程度、骨道形状、相关因素及其与临床效果的关系。方法回顾性研究应用胭绳肌腱重建ACL手术后骨道的变化,通过X线片测量ACL重建术后的骨道直径。对51例患者行ACL重建手术,其中男性30例,女性21例。所有患者均获随访,平均随访时间16个月。主要研究及观察指标：患者性别、年龄、身高等因素,移植物的固定方式,随访时的关节活动度、膝关节稳定性检查（KT2000）及肌力恢复情况,以及股骨和胫骨的骨道直径、骨道位置和角度等。数据分析采用统计学卡方检验及相关性分析。结果前交叉韧带重建术后的骨道增宽率股骨85％-94％,胫骨65％;增宽程度股骨51％-53％,胫骨40％～44％。胫骨骨道增宽的形态以O型（冠位片）及V型（矢位片）最常见。骨道增宽与年龄、身高及体重指数相关。股骨骨道位置偏前会引起股骨骨道的增宽,股骨骨道角或胫骨骨道角越小,则股骨骨道越容易增宽。结论以腘绳肌腱为移植物重建前交叉韧带手术,术后骨道增宽的发生率与程度,股骨骨道较胫骨骨道明显。骨道增宽与患者年龄、身高以及骨道定位相关,其中股骨和胫骨骨道的位置及角度是引起术后骨道增宽的主要因素之一。骨道增宽与KT2000结果和术后肌力恢复情况相关。     

关节镜下解剖等长重建技术在重建前交叉韧带中的应用

[目的]探讨前交叉韧带(ACL)解剖等长重建技术在关节镜下应用的可行性及近期疗效.[方法]对20例前交叉韧带损伤行关节镜下ACL重建木.采用前交叉韧带解剖等长重建技术钻胫骨、股骨骨道.移植物用LARS人工韧带11例,用四股半腱肌股薄肌腱9例.LARS人工韧带用2枚界面螺钉固定韧带,四股半腱肌股薄肌腱股骨端用Endobutton固定、胫骨端用可吸收界面螺钉固定.[结果]手术时间LARS人工韧带组30～80 min,平均56 min.四股半腱肌股薄肌腱组80～120 min,平均100 min.20例均随访6～12个月,平均9个月.根据Lysholm膝关节功能评分,LARS人工韧带组术前评分22～65分(36.72±15.54)分;术后6个月评分80～98分(90.45±4.68)分(t=10.535,P＜0.01).四股半腱肌股薄肌腱组术前评分20～60分(37.11±12.26)分;术后6个月评分75～87分(80.44±4.16)分(t=9.615,P＜0.01).术后6个月LARS人工韧带组与四股半腱肌股薄肌腱组评分在统计学上有显著差异(t=10.569,P＜0.01).[结论]前交叉韧带解剖等长重建技术在关节镜下重建前交叉韧带术中操作简便,效果可靠,值得推广.LARS人工韧带组近期疗效明显优于四股半腱肌股薄肌腱组.     

关节镜下横穿钉固定重建膝关节前交叉韧带的临床疗效分析

[目的]观察关节镜下股骨侧应用横穿钉(Transfix)固定,胫骨侧界面螺钉(Interference)结合门型钉固定自体腘绳肌腱或同种异体肌腱重建膝关节前交叉韧带的临床疗效。[方法]膝关节前交叉韧带重建患者117例,所有患者均应用股骨侧横穿钉(Transfix)固定,胫骨侧界面螺钉(Interference)结合门型钉固定行前交叉韧带单束重建,其中使用自体腘绳肌腱患者81例,使用同种异体肌腱患者36例,观察此固定方法的可靠性及近期疗效,使用Lysholm评分及IKDC 2000评价手术前后膝关节功能。[结果]103例患者获得随访,随访时间12～26个月(平均18个月),关节活动度正常。平均Lysholm评分由术前的(57.60±5.74)分提高到术后的(94.55±2.38)分(P0.05)。IKDC 2000评分96例正常,6例(5.8%)接近正常,1例(1%)异常。自体腘绳肌腱组和同种异体肌腱组患者的物理检查及功能评分无明显差异。[结论]股骨侧横穿钉固定,胫骨侧界面螺钉结合门型钉固定重建膝关节前交叉韧带的手术方式近期疗效肯定,移植物固定可靠,手术操作安全。应用自体及同种异体肌腱进行重建都具有良好的临床效果,可根据患者的病情及主观要求进行选择。     

关节镜下前交叉韧带重建术股骨侧2种不同固定方式的疗效分析

目的分析研究关节镜下前交叉韧带重建过程中股骨侧肌腱使用Endobutton悬吊系统及Rigidfix横穿钉系统2种不同固定方式的疗效差异。方法笔者自2010-02—2016-05诊治50例前交叉韧带损伤,重建前后分别进行前抽屉试验、Lachman试验、轴移试验。采用CT测量骨隧道扩大情况,进行对比分析。结果所有患者获得平均20.5(3~38)个月随访,满意度良好;2组术后Lysholm评分均有明显提高,差异有统计学意义(P0.05)。2组术后Lysholm评分比较差异无统计学意义(P0.05)。经CT测量发现,Endobutton组骨隧道扩大较Rigidfix组明显,差异有统计学意义(P0.05)。结论 Endobutton悬吊系统及Rigidfix横穿钉系统都是前交叉韧带重建术股骨侧肌腱的有效固定方式。与Rigidfix横穿钉系统相比,股骨端采用Endobutton悬吊系统固定更易引起骨隧道扩大。     

PRP明胶海绵复合物在前交叉韧带重建术后腱骨愈合的作用

[目的]观察复合有富血小板血浆(platlet rich plasma,PRP)明胶海绵复合物的自体肌腱移植物对前交叉韧带重建术后骨隧道与肌腱间愈合过程的影响,探讨其在腱与骨愈合中发挥的效果。[方法]新西兰大白兔36只,无菌条件下获取自体PRP,制备PRP明胶海绵复合物,左下肢行自体跟腱移植前交叉韧带重建术。A组(实验组)使用PRP明胶海绵复合物;B组(对照组1)使用PRP;C组(对照组2)仅为肌腱。植入2、4、8、12周后,制作标本,进行大体及HE、Masson染色和TGF-β1免疫组化观察。[结果]A组标本大体观察:前交叉韧带连续性及张力良好,术后2周骨隧道口见少量瘢痕组织;4周骨道口见小部分骨样组织,8周骨道口较多瘢痕呈现,12周骨道口现较多骨样成分。组织学观察:HE染色显示,A组出现Sharpey样纤维和软骨细胞明显早于B组和C组;同样在Masson结果中,A组出现有规则的胶原纤维也明显多于B组和C组。TGF-β1免疫组织化学观察:2、4、8周,A组阳性率明显高于B、C组,差异具有统计学意义(P<0.05)。而在术后12周时,各组之间的表达无明显差异(P>0.05)。[结论]PRP明胶海绵复合物可促进前交叉韧带重建后腱骨的早期愈合。     

腘绳肌腱结嵌压固定法重建交叉韧带的临床应用与生物力学研究

目的探讨腘绳肌腱结嵌压固定法重建交叉韧带的可行性。方法对52例陈旧性前、后交叉韧带损伤患者在关节镜下行双股腘绳肌腱中间打结,嵌入瓶颈状股骨隧道内固定,胫骨端采用肌腱编织缝合在骨桥上打结固定,重建交叉韧带。其中前交叉韧带25例,前、后十字韧带同时重建15例,后交叉韧带12例。生物力学实验采用猪膝关节。股骨端固定分为肌腱结嵌入组(n=13)和骨髌腱骨(B PT B)介面螺钉固定组(B PT B介面钉组,n=11)。胫骨端固定分为肌腱编织缝合线在骨桥打结组(n=7)、肌腱编织缝合介面螺钉组(n=8)。进行最大拔出强度、最大位移和固定刚度等力学实验。结果术后随访49例,平均14 6个月,Lanchman试验阴性46例,阳性3例。术后Lysholm评分由术前56 7分提高到92 8分。按膝关节疗效评定标准,优46例,良3例。生物力学实验最大拔出强度肌腱结嵌入组高于B PT B介面钉组;固定刚度肌腱结嵌入组小于B PT B介面钉组;最大位移肌腱结嵌入组大于B PT B介面钉组。胫骨端固定抗拉强度和刚度骨桥打结组优于介面螺钉组。结论腘绳肌腱结嵌压固定重建交叉韧带生物力学抗拉强度能满足生理需求,方法可行;可克服位移因素,降低韧带松弛率,提高疗效。     

复合腱-骨固定的生物力学及形态学研究

[目的]探讨不同固定方式对前交叉韧带重建中股骨隧道内移植物的影响。[方法]成年猪膝关节64个,以足部肌腱为移植物模拟前交叉韧带重建股骨侧腱-骨固定,固定方式随机分为5组,分别采用7 mm×23 mm界面螺钉固定(A组)、6 mm×23 mm界面螺钉固定(B组)、聚酯缝线4孔微钢板股骨外口固定(C组)、Endobutton固定(D组)和B与C固定组合(E组),进行生物力学测试并观察股骨隧道内口移植腱横截面积及厚度。[结果]持续施加200 N的轴向牵拉力条件下,A、B、E组轴向位移均为0 mm,C组的轴向位移为(5.51±0.53)mm,D组的为(5.49±0.51)mm;C组和E组移植物轴向位移差异有统计学意义(P<0.05)。最大损毁强度A组为(350.62±17.81)N,B组为(260.71±18.44)N,C组为(650.50±24.34)N,D组为(565.66±21.63)N,E组为(800.53±30.21)N,组间比较差异有统计学意义(F=291.352,P<0.01)。移植物内口横截面形态,A组的横截面呈"新月状",足印处移植物最大宽度为1 mm,横截面积为(10.06±0.18)mm~2;B组呈近似"满月状",足印处宽度为8 mm,面积为(38.16±0.32)mm~2;C组呈"满月状",足印处宽度为8 mm,面积为(40.02±0.21)mm~2;E组呈近似"满月状",足印处厚度为8 mm,面积为(38.86±0.29)mm~2。A、E组间比较差异有统计学意义(F=290.568,P<0.01)。此外,A组的挤压程度较重,B组较轻,C组的无挤压,E组同B组。[结论]复合固定技术不仅提供了足够的移植物初始固定强度,还有效避免了"雨刷和蹦极效应",减少了螺钉对肌腱的挤压切割,有利于移植物骨愈合和足印重建。     

前交叉韧带重建胫骨栓桩与挤压螺钉固定的比较

[目的]评估膝关节前交叉韧带损伤胫骨栓桩固定及可吸收挤压钉固定的疗效。[方法] 2011～2016年治疗膝关节前交叉韧带损伤患者61例,股骨骨道均以Endobutton固定,其中胫骨骨道栓桩固定25例,胫骨骨道可吸收挤压钉固定36例,手术前后行Lachman试验、IKDC和Lysholm评分,以评估手术疗效。[结果] 61例患者均顺利接受手术,术中无血管神经损伤等严重并发症。术后栓桩组平均随访(13.62±1.23)个月,挤压钉组随访(14.72±1.16)个月。末次随访时栓柱钉组25例患者和挤压钉组36例患者均无明显疼痛、交锁和打软腿症状,前抽屉试验、轴移试验及Lachman试验均为阴性。两组的ROM均随时间延长有所增加,但差异无统计学意义(P0.05),不同时间点两组间ROM的差异均无统计学意义(P0.05)。术后6、12个月时两组的KT-1000值均较术前显著减少,差异有统计学意义(P0.05),而两组术后6个月与12个月的KT-1000值差异均无统计学意义(P0.05)。相同时间点两组间KT-1000值的差异均无统计学意义(P0.05)。随着时间延长,两组患者的Lysholm评分和IKDC 2000评分均显著增加,两组患者不同时间点的差异均有统计学意义(P0.05),但相同时间点两组间Lysholm评分和IKDC2000评分的差异均无统计学意义(P0.05)。[结论]前交叉韧带重建胫骨骨道可吸收挤压螺钉固定与皮质骨螺钉栓桩固定术后均取得较好疗效,两组相比较无明显差别,胫骨侧栓桩固定也是一种可靠的固定方法。     

单股骨胫骨骨隧道双束重建膝ACL胫骨端移植物张力差异化固定的疗效

目的研究关节镜下单股骨胫骨骨隧道双束自体半腱肌重建膝关节前交叉韧带(anterior cruciate ligament,ACL),胫骨端移植物张力差异化固定的临床效果。方法回顾分析我科2016年1月至2016年10月关节镜下行ACL重建患者32例,移植物均选用自体伤侧半腱肌肌腱,股骨骨道均应用带袢纽扣钢板悬吊固定,胫骨端均用纽扣钢板悬吊固定,随机分为两组。对照组:常规单股骨胫骨骨隧道单束重建ACL(n=16),实验组单股骨胫骨骨隧道双束重建ACL,胫骨端移植韧带张力差异化固定(n=16)。通过术后随访查体,膝关节功能Lysholm和Tegner评分进行膝关节功能评价,评价实验组的临床效果。结果所有患者均获得随访,平均随访时间12个月,两组患者术后均无关节感染发生,前抽屉试验、Lysholm和Tegner膝关节功能评分均较术前显著改善(P0.05),但两组之间无明显差异(P0.05)。结论实验组可获得膝关节良好的向前稳定性,手术操作简单、固定可靠、近期疗效满意,但与对照组相比,膝关节前后稳定性及关节功能评分无明显差异,两组膝关节旋转稳定性及远期疗效差异有待进一步研究。     

国人腘绳肌腱移植不同固定方式重建ACL的生物力学研究

[目的]探讨腘绳肌腱移植重建ACL股骨与胫骨侧采用不同固定方式的生物力学特性。[方法]采用新鲜冷冻尸体膝关节标本,腘绳肌腱移植,股骨侧分别用Endobutton(n=8)、Rigidfix(n=8)、肌腱结(n=8)和界面螺钉固定(n=8)。胫骨端采用可吸收界面螺钉(n=7)和Intrafix(n=7)固定,模拟ACL重建。进行循环载后位移、抗拉刚度、失效载荷、最大载荷等生物力学。[结果]失效载荷和最大载荷:EndobuttonRigidfix肌腱结界面螺钉固定法,差异有统计学意义(P0.01),Rigidfix和界面螺钉之间的差异有统计学意义(P0.05)。抗拉刚度:Rigidfix=肌腱结界面螺钉固定Endobutton。循环载荷位移:肌腱结固定组Rigidfix固定组Endobutton固定组界面螺钉固定组。胫骨端最大载荷:Intrafix固定组可吸收界面螺钉组,两者之间差异有统计学意义(P0.05);100 N、400 N抗拉刚度两组间差异无统计学意义(P0.05)。[结论]采用Endobutton、Rigidfix、intrafix、肌腱结和界面螺钉ACL重建固定均可满足力学需求;Rigidfix和Intrafix固定系统较界面螺钉固定更具有生物力学优势。     

Hamstring腱在体内重塑与转归的组织学研究

目的探讨游离Hamstring腱作为替代腱重建前十字韧带（anterior cruciate ligament，ACL）后在体内的重塑与转归过程，初步确定其术后在体内成熟的时间。方法33例关节镜下自体同侧游离4-5股Hamstring腱重建ACL的患者在行关节镜下再视手术时，于移植腱体中下段取活检组织进行组织学观察。重建术至再视手术的平均时间为11．9个月。替代腱依据重建术至再视手术的时段分为1月～、4月～、7月～、10月～、13月～、18月～和25月～组。将替代腱与正常ACL和半腱肌腱组织进行对比。结果重建ACL的Hamstring腱随植入时间延长，组织结构呈现其胶原纤维由不规则排列逐步向同向排列，排列不规则的菱形成纤维细胞逐步向较规则排列的椭圆形类纤维细胞转变，且细胞数目逐渐减少，血管腔数目也不断减少。上述的重塑变化主要发现在7月～组以前，其后各组重塑变化过程缓慢。结论自体游离Hamstring腱重建ACL术后具有良好的早期存活、加快再血管化和重塑过程的组织特性。其术后的重塑与成熟过程与自体髌腱相似，自体Hamstring腱在体成熟的时间为7-9个月。     

Effect of PEEK polymer on tunnel widening after hamstring ACL reconstruction

The purpose of this study was to evaluate the effect of the AperFix device (Cayenne Medical, Inc, Scottsdale, Arizona), composed of polyetheretherketone (PEEK) polymer, on tunnel widening after hamstring anterior cruciate ligament (ACL) reconstruction as compared with 2 other fixation devices: the TransFix (Arthrex, Inc, Naples, Florida) and the EndoButton (Smith & Nephew Endoscopy, Mansfield, Massachusetts). Sixty-seven patients with isolated total ACL ruptures who underwent arthroscopically assisted reconstruction using hamstring autografts at the authors' institution were included in the study. Patients were assigned into 1 of 3 groups in a nonrandomized fashion: AperFix (n=18), TransFix (n=29), and EndoButton (n=20). Mean follow-up was 30 months. Tunnel widening measurements were performed on anteroposterior and lateral digital plain radiographs taken in postoperative week 1 and at final follow-up. Laxity testing, Lysholm scoring, and arthrometric evaluation were performed.All 3 graft fixation devices resulted in significant tunnel widening in both tibial and femoral tunnels at final follow-up when compared with the immediate postoperative period. Tunnel widening between groups was not significantly different in terms of coronal and sagittal femoral tunnel diameters. Tibial tunnel diameter increase in the sagittal plane in the EndoButton group was significantly smaller than that in the TransFix and AperFix groups. No correlation was found between the amount of tunnel enlargement and clinical outcomes of ACL surgery. This study's findings suggest that tunnel enlargement after ACL reconstruction is influenced by the type of graft fixation on the tibial side irrespective of clinical outcome, and PEEK polymer does not have an effect on tunnel widening after hamstring ACL reconstruction.     

Histological findings of tendon-bone healing following anterior cruciate ligament reconstruction with hamstring grafts

BACKGROUND: The purpose of the study was the histological examination of tendon-bone healing of hamstring grafts after anterior cruciate ligament (ACL) reconstruction. METHODS: During five arthroscopies done 6-14 months after ACL reconstructions, biopsies of the wall of the former drilled femoral canal were obtained. Four patients were primarily operated on using a suspending device (Endobutton, Acufex Microsurgical, Mansfield, MA, USA, and Transfix, Arthrex, Naples, FL, USA) for femoral fixation, one patient was reconstructed with a biodegradable interference screw directly inserted between the tendon and the wall of the canal. Biopsies were obtained using a tube harvester during re-arthroscopy. Three grafts were stable, two grafts were unstable, and revision of the ACL was performed. RESULTS: Histologically, in the four cases of reconstruction with a button or a rectangular pin, biopsies resembled granulation tissue without insertion of fibers between the tendon tissue and the bony wall. A wide area of woven bone was noted adjacent to the pre-existing lamellar bone. In contrast, the tendon-bone junction in the knee reconstructed with a biodegradable interference screw resembled a zone of metaplastic fibrous cartilage between the tendon graft and the lamellar bone. Collagen fibers connecting the tendon-bone interface occurred under polarized light microscopy. CONCLUSION: We conclude that the use of hamstring grafts for ACL reconstruction can lead to different histological pattern of tendon-bone healing. Micromotion of the hamstring graft inside the drilled canal can be play a role in tendon-bone healing.     

In vitro comparison of elongation of the anterior cruciate ligament and single- and dual-tunnel anterior cruciate ligament reconstructions.

This study evaluated strain in the normal anterior cruciate ligament (ACL) and compared it to four different double-strand hamstring tendon reconstructive techniques. Seventeen fresh-frozen knees from 11 cadavers were tested. The strain in the anteromedial and posterolateral bands of the native ACL and their equivalents in four autograft techniques were measured using differential variable reluctance transducers. The anteromedial band of the intact ACL shortened from 0 degree -30 degrees of flexion, then lengthened to 120 degrees; the posterolateral band of the intact ACL shortened from 0 degree - 120 degrees of flexion. Following ACL excision, these knees underwent reconstruction with double-strand hamstring tendons with either single tibial and femoral tunnels, single tibial and dual femoral tunnels, dual tibial and single femoral tunnels, or dual tibial and dual femoral tunnels. With the exception of the dual-band, dual-tunnel technique, all of the procedures placed greater strain on the reconstructive tissues than was observed on the native ACL, after approximately 30 degrees of flexion. These results indicate that dual-band hamstring tendon reconstructions placed with single tibial and femoral tunnels do not address the complexity of the entire ACL. Rather, these procedures appear to only duplicate the effect of the anteromedial band, while perhaps overconstraining the joint as a result of its inability to reproduce the function of the posterolateral band. During rehabilitation following ACL reconstruction, therefore, only from 0 degree - 30 degrees of the graft tissues are not significantly strained. Dual tibial and femoral tunnel techniques should be evaluated further to more closely recreate knee kinematics following ACL reconstruction.     

Editorial Commentary: Tunnel Widening After Anterior Cruciate Ligament Reconstruction May Increase Laxity and Complicate Revision

Tunnel widening (TW) after anterior cruciate ligament (ACL) reconstruction has been a research area of interest in ACL reconstruction. It has been demonstrated that femoral tunnels enlarge anteriorly and distally (ie, the direction where the mechanical traction force of the graft works) rather than concentrically after anatomic double-bundle ACL reconstruction using hamstring autografts. This finding suggests that the wall supporting the graft moves closer to the direction of the pull, leading to increased laxity of the knee joint due to TW. The causes of TW are presumed to be multifactorial, with both biological and mechanical features. Biological factors include osteolytic cytokines that enter the space between the graft and the bone through the synovial fluid. Mechanical factors include longitudinal graft motion by extracortical femoral fixation (known as the bungee effect), transverse graft motion (also called the windshield-wiper effect), improper graft placement, higher initial graft tension, accelerated rehabilitation, and so on. Although TW does not seem to affect short-term clinical outcomes from studies published to date, it is plausible to speculate that the expansion of the bone tunnel (ie, the edge where the graft tendon is fixed) would theoretically increase joint laxity to some extent, and it would be premature to conclude that TW has no effect on clinical outcomes relative to graft–tunnel micromotion. In addition, there is a general consensus that the presence of expanded tunnels often severely complicates revision ACL reconstruction. In ACL reconstruction using the hamstring tendon, it is necessary to take into account the possibility of a shift in the tunnel position when determining the location of the femoral tunnel.     

Isolierter Bündelersatz bei Partialruptur des vorderen Kreuzbandes

Objective

Partial augmentation of isolated tears of the anteromedial and posterolateral bundle of the anterior cruciate ligament (ACL) with autologous hamstring tendons. The intact fibers of the ACL are preserved.

Indications

Symptomatic isolated tear of the anteromedial or posteromedial bundle of the ACL or rotational instability after ACL reconstruction with malplaced tunnels (e.g., high femoral position)

Contraindications

In revision cases: loss of motion due to malplaced ACL and excessive tunnel widening of the present tunnels with the risk of tunnel confluence.

Surgical technique

Examination of anterior–posterior translation and rotational instability under anesthesia. Diagnostic arthroscopy, repetition of the clinical examination under direct visualization of the ACL, meticulous probing of the functional bundles. Resection of ligament remnants, preparation/preservation of the femoral and tibial footprint. Harvesting one of the hamstring tendons, graft preparation. Positioning of a 2.4 mm K-wire in the anatomic center of the femoral anteromedial/posterolateral bundle insertion, cannulated drilling according to the graft diameter. Positioning of a 2.4 mm K-wire balanced according to the femoral tunnel at the tibia, cannulated drilling. Insertion of the graft and fixation.

Postoperative management

Analogous to that for ACL reconstruction.     

Hamstring tendon autograft better than bone patellar-tendon bone autograft in ACL reconstruction: a cumulative meta-analysis and clinically relevant sensitivity analysis applied to a previously published analysis

Background Current debate on treatment options for anterior cruciate ligament (ACL) reconstruction complicate the choice between hamstring and bone patellartendon bone autografts. We hypothesized a priori that cumulative meta-analysis (a form of sensitivity analysis) might show that the evidence for reduction of morbidity by hamstring grafts could have been reached at an earlier time. Furthermore, we hypothesized a priori that modern state-of-the-art hamstring graft fixation technique would give similar results regarding stability as bone-patellar tendon-bone autografts.

Methods We performed a cumulative meta-analysis and sensitivity analysis based on femoral graft fixation techniques to compare hamstring autograft and bonepatellar tendon-bone autografts in ACL reconstruction derived from a previously published meta-analysis.

Results Cumulatively, that hamstring autograft reduces anterior knee pain had already reached statistical significance in 2001 (relative risk 0.49 (95%CI: 0.32-0.76; p = 0.001, I2 = 0%)). The modern endobutton hamstring graft fixation technique (2 studies) yielded similar stability in the Lachman test as bone-patellar tendon-bone grafts, with a relative risk of 1.1 (95%CI: 0.82-1.5; p = 0.6, I2 = 0%). Exclusion of the endobutton group explains the increased laxity in the hamstring graft group.

Interpretation Cumulative meta-analysis strengthens the evidence for reduced morbidity using hamstring tendon autograft for anterior cruciate ligament reconstruction. Sensitivity analysis focusing on state-of-the-art hamstring graft fixation techniques further weakens the evidence that bone-patellar tendon-bone autografts provide better stability.     

Kniegelenklaxizität beim vorderen Kreuzbandersatz

Background

The use of interference screws for femoral graft fixation in anterior cruciate ligament (ACL) reconstruction with hamstring grafts can result in rotation of the graft around the screw leading to changes in the final position of the graft within the bone tunnel.

Material and methods

In a prospective study 107 patients (54 right and 53 left knees) underwent ACL reconstruction with a hamstring tendon autograft. Femoral fixation of the graft was performed with a standard right-thread screw in all cases. Patients were assessed at 6 months postoperatively with the international knee documentation committee (IKDC) standard evaluation including instrumented laxity measurements and the results were compared between right and left knees.

Results

A significantly higher postoperative anterior laxity was observed in left knees with a negative Lachman test in only 64 % of the cases compared with 87 % in the group of right knees. Accordingly, instrumented laxity measurements of the reconstructed knee compared with the contralateral knee revealed significant differences between left and right knees (left knees 1.8±1.2 mm and right knees 1.0±1.4 mm)

Conclusions

This study demonstrates the importance of femoral graft positioning and its sensitivity to multiple influencing factors. The use of standard right-thread interference screws for femoral graft fixation in the mirrored situation of right and left knees may produce a systematic error in ACL reconstruction. Due to a possible rotation of the graft around the screw, the final position of the transplant may vary thus leading to significant changes in anterior translation of the operated knee.