Associations between isometric quadriceps strength characteristics,knee flexion angles,and knee extension moments during single leg step down and landing tasks after anterior cruciate ligament reconstruction

BackgroundIt is unclear of how peak knee extension torque and early rate of torque development outcomes are related to lower extremity loading and sagittal plane movement in activities of daily living and landing tasks despite consistent deficits after anterior cruciate ligament reconstruction. The purpose of this cross-section study is to assess the ability of quadriceps strength characteristics to predict movement patterns during a step down and single leg drop crossover hopping tasks.MethodsFifty-two individuals with a unilateral history of anterior cruciate ligament reconstruction completed three trials of the step down and crossover hopping tasks on their involved limb. Participants completed three isometric knee extension contractions at 90° knee flexion with visual feedback to assess peak knee extension torque and rate of torque development during the first 0–100 ms and 100–200 ms of the contraction.FindingsPeak knee extension torque explained the greatest variance in peak knee extension moment (R² = 40.4%, p < 0.001) and knee flexion angle (R² = 46.7%, p < 0.001) during the crossover hop landing. Rate of torque development (0–100 ms) was the only predictor of knee flexion angle (R² = 19.8%, p = 0.01) at initial contact during the crossover hopping landing. Rate of torque development (100–200 ms) explained 17.6% of the variance in peak knee extension moment during the step down (p = .03).InterpretationPeak knee extension torque and early rate of torque development outcomes demonstrate limited relationships between movement of activities of daily living and sport-specific tasks. These limitations should be considered when interpreting the results of isometric strength testing in a clinical setting.     

Muscular isokinetic strength recovery after knee anterior cruciate ligament reconstruction revision: Preliminary study

MethodThirty-nine revision of ACL reconstructions were evaluated: 23 primary ACL reconstructions with bone-patellar tendon-bone graft (BPTB) revised with hamstring tendon (HT) grafts, 10 primary ACL reconstructions with HT grafts revised with ipsilateral BPTB graft (iBPTB) and finally 6 primary ACL reconstructions with BPTB grafts revised with contralateral BPTB (cBPTB) grafts were compared with 78 primary ACL reconstructions (46 HT grafts and 32 BPTB grafts). Recovery of isokinetic muscle strength was evaluated at 4, 6 and 12 months post-revision surgery.ResultsDeficits in muscle strength at 12 months post-revision ACL surgery were comparable to the one observed for primary ACL reconstruction with the same technique. At 4 and 6 months post-surgery, strength deficits for the knee extensors were less pronounced after revision ACL reconstruction with HT grafts (25% ± 16 vs. 37% ± 16; P < 0.001) and iBPTB grafts (41% ± 11 vs. 17% ± 17; P < 0.001).DiscussionLower strength deficits for the knee extensors after revision ACL reconstruction with HT grafts can be explained by a less intensive rehabilitation program due to lower stakes in resuming sport activities. With cBPTB, donor-site morbidity could explain the decreased strength deficits for knee extensors.ConclusionDeficits in isokinetic muscle strength after ACL revision seem similar to the ones observed after primary ACL reconstruction with the same surgical technique.     

平衡促进训练对膝关节前交叉韧带损伤重建术后患膝本体感觉的影响

目的:研究平衡促进训练对膝关节前交叉韧带(ACL)损伤重建术后患膝本体感觉的影响。方法:选取124例ACL损伤重建术后患者,全部进行常规康复训练12周,术后第12周采用随机数字法分成两组(对照组62例,训练组62例),训练组在第12周开始进行平衡促进训练,持续至第16周;对照组继续进行患肢肌力和步态训练,持续至第16周。采用专业平衡功能评定系统,分别在术后第12周和第16周对两组进行平衡功能测定。结果:术后第16周测定结果:①睁眼状态下,训练组与对照组在指标LFS指数和覆盖90%椭圆区域面积指数无显著差异(P>0.05)。②闭眼状态下,训练组与对照组在指标LFS指数和覆盖90%椭圆区域面积指数差异具有显著性意义(P<0.05)。结论:平衡促进训练对ACL损伤重建术后患者膝关节本体感觉能力恢复具有显著提高作用。     

Effect of lower limb dominance on knee joint kinematics after anterior cruciate ligament reconstruction

Background

Normal ambulatory kinematics of the knee joint is often not fully restored after anterior cruciate ligament reconstruction, which may increase the risk for cartilage degeneration and premature osteoarthritis in the involved knees. Lower limb dominance may have impacts on knee joint kinematics after anterior cruciate ligament reconstruction, which may lead to a different prevalence of cartilage degeneration. This study aimed to evaluate the knee joint kinematics among patients with reconstruction on the dominant and non-dominant side.

Methods

Forty-one subjects with unilateral anterior cruciate ligament reconstruction (19 dominant, 22 non-dominant) were recruited after being discharged from rehabilitation programs. Twenty healthy subjects were recruited as the control group. Six degrees-of-freedom tibiofemoral motion during level walking was determined using a redundant point cluster-based marker set. Tibiofemoral joint motion and its bilateral differences were compared within each group and between groups.

Findings

The non-dominant reconstructed knees had less extension compared to their contralateral knees at heel strike and during middle stance phase (P = 0.02); whereas, the dominant reconstructed knees exhibited significantly reduced varus rotation (− 2.1° on mean, P = 0.027) and internal tibial rotation (P = 0.034) compared to their contralateral knees during both stance and swing phases.

Interpretation

The results show that different kinematics has been developed between the involved dominant and non-dominant knees after anterior cruciate ligament reconstruction, especially the secondary rotations. The differences are consistent with the unequal prevalence of cartilage degeneration in the knee joint. The findings demonstrated that the lower limb dominance had a significant effect on post-surgery knee kinematics.     

膝关节前交叉韧带重建术后患者功能康复的相关因素分析

目的探讨影响膝关节前交叉韧带重建术后患者功能康复的相关因素。方法采用一般自我效能感量表和社会支持评定量表,对480例膝关节前交叉韧带重建术后患者进行调查。结果膝关节前交叉韧带重建术后患者功能康复处于中等水平。康复完成与年龄呈负相关(P0.01),与文化程度、一般自我效能、社会支持水平呈正相关(P0.01)。结论针对膝关节前交叉韧带重建术后患者开展延续性护理,增强自我效能和建立完善的社会支持系统,针对患者的年龄和文化程度,实施个性化护理干预,有利于促进患者康复。     

Single-leg assessment of postural stability and knee functional outcome two years after anterior cruciate ligament reconstruction

ObjectiveTo analyse postural stability and the single-leg hop for distance in subjects 2 years after anterior cruciate ligament reconstruction (ACLR), in comparison with an age- and activity-matched control group.Design and settingSubjects reported to a sports medicine or athletic training research laboratory for testing.SubjectsTwenty-six subjects having undergone ACLR and 26 age- and activity-matched controls were selected to participate in this study. An arthroscopically-assisted, central, one-third bone-patellar tendon procedure was used to repair the ACLs.MeasurementsOne-leg stance postural stability was measured with the NeuroCom Balance Master^® platform system. We recorded the single-leg hop for distance as an objective measure of function.ResultsWe found a significant difference (p < 0.05) between the ACLR and control subjects in terms of the one-leg stance sway velocity (knee fully extended) on the operated side.ConclusionsAfter ACLR (mean time postoperatively: 24 ± 1 months), single-leg hop for distance score was normal, when compared with the contralateral limb. Our results indicate that 2 years after surgery, single-limb postural stability in the ACLR group differed significantly from that in the control group. The persistence of poor stability control may be correlated to an impairment in proprioception.     

前交叉韧带重建后的感染

背景：前交叉韧带重建后感染的发生率比较低,但这种感染会导致灾难性的结果,目前对这种感染的诊断和治疗还没有取得一致的意见。目的：探讨导致前交叉韧带重建术后感染的原因、如何早期诊断,并探讨合适的治疗方案,以尽量保护膝关节的功能。方法：以＂anterior cruciate ligament,reconstruction,infection＂为检索词,检索Pubmed数据库（2007至2012年）;以＂前交叉韧带,重建,感染＂为检索词,检索万方数据库（2007至2012年）。以与前交叉韧带重建后感染的相关文献为评价指标,纳入与前交叉韧带重建后感染相关的内容,排除重复研究。结果与结论：细菌污染手术工具或者韧带移植物是导致前交叉韧带重建后感染的最常见原因,移植物固定的方式和重建后感染之间可能有一定的关系。典型的前交叉韧带重建术后感染的症状和普通的化脓性关节炎的症状类似,但有的前交叉韧带重建后感染的病例并没有感染的典型表现。前交叉韧带重建后感染的诊断需要依靠临床症状、实验室检查（C-反应蛋白和血沉）、膝关节穿刺等方法。大多数外科医师选择静脉使用敏感的抗生素、膝关节灌洗并保留移植物作为自体移植物重建前交叉韧带后感染的首选治疗方法。当感染难以控制或者移植物看起来确实有感染迹象时应该考虑取出移植物。     

关节镜下前交叉韧带重建术后膝关节感染的诊断和治疗

目的 探讨膝关节镜下前交叉韧带(ACL)重建术后膝关节感染的诊断和治疗方法.方法 收集2015年1月-2019年12月6例行关节镜ACL重建术后膝关节感染患者的临床资料.其中,4例采用抗感染药物治保守疗,2例经二次膝关节镜关节腔清理术治疗.结果 所有患者均得到治愈,体温恢复正常,膝关节局部症状消失,血液学指标恢复正常....     

膝关节十字韧带损伤后膝关节屈伸力量及本体感觉的重建

背景:膝关节十字韧带重建术后功能恢复快慢与好坏直接影响运动员的训练效果及比赛成绩. 目的:评定膝关节十字韧带损伤患者膝关节屈伸肌力量和本体感觉的改善效果.设计、时间及地点:病例分析,2001-09/2006-09陕西省人民医院、西京医院、北京大学第三医院病例资料.对象:在关节镜下进行十字韧带修补术的篮球、排球、足球女运动员共32名.平均年龄(19.6±2.7)岁,平均体质量(61.6±4.51)kg,平均身高(177.8±2.39)cm,平均训练年限(10.4±1.67)年.方法:通过查阅文献资料,对国内外多种膝关节韧带康复模式进行汇总,向有关专家咨询并确立康复方案.结合等速向心力量训练和平衡板训练、固定自行车练习、半蹲训练、步行灵活性训练、慢跑等本体感觉强化训练,制定详尽的康复训练模式.主要观察指标:术前及术后1年膝关节力量和本体感觉指标评定.结果:患肢术后1年伸肌力量、屈肌力量、屈肌力量/伸肌力量高于术前(P < 0.01).患者术后1年Lysholm 评分、Lysholm 不稳评分、单足跳距离均高于术前(P < 0.05);双膝KT-2000差值小于术前( P < 0.05) .结论:本体感觉强化训练有助于损伤膝关节静力性和动力性稳定结构及本体感觉的恢复.通过等速训练能很好恢复大腿肌肉功能.     

可调式膝关节支具在前交叉韧带重建术后康复护理中的应用

[目的]探讨前交叉韧带重建术后应用可调式膝关节支具的康复护理效果。[方法]选取2009年3月—2011年9月前交叉韧带断裂病人32例(32膝),在前交叉韧带重建术后运用可调式膝关节支具指导病人康复锻炼,并应用Lysholm评分对膝关节功能恢复情况进行评定。[结果]32例病人术后7个月随访时膝关节Lysholm评分(87.25分±4.65分)较术前(54.75分±9.71分)明显提高(t=6.04,P<0.01)。[结论]可调式膝关节支具可帮助病人行早期适宜功能锻炼,提高临床疗效。     

Functional measurement of knee joint position sense after anterior cruciate ligament reconstruction

OBJECTIVE: To examine for differences in joint position sense (JPS) between knees with reconstructed anterior cruciate ligaments (ACLs) and uninjured knees by using a functional weight-bearing measurement method. DESIGN: Two-way repeated-measures in a convenience sample. SETTING: An Australian university rehabilitation laboratory. PARTICIPANTS: Nine subjects presenting at 12 to 16 months after unilateral ACL reconstruction using the semitendinosus/gracilis graft who were recruited from 2 orthopedic surgeons. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: JPS of the reconstructed and uninjured knees was examined by using the Peak Motus motion measurement system to record target joint angles and to calculate reproduced angles after limb movement into flexion and extension, performed in a weight-bearing position. RESULTS: There were no significant differences in JPS between reconstructed and uninjured knees (P=.68) or between the flexion and extension tasks (P=.47). CONCLUSION: There was no deficit in knee JPS 12 to 16 months after ACL reconstruction, as measured by a functional weight-bearing method. Further studies should examine the clinical utility of the method as a way to evaluate functional aspects of knee joint proprioception.     

Deficient knee joint biomechanics in bilateral jumping after anterior cruciate ligament reconstruction

BackgroundThe purpose of this study was to analyze sagittal-plane knee biomechanics in individuals with ACL reconstructions in bilateral countermovement jumps. This aimed to determine potential knee compensation strategies during a high-demanding symmetrical movement task from pre to six months post-ACL reconstruction.Methods20 ACL-reconstructed individuals were tested pre-operatively, and then seven weeks, three months, and six months after reconstruction. Additionally, a matched control group was analyzed. Data were sampled with 3D motion capture and two force plates. The following kinematic data were analyzed: peak knee flexion during countermovement, knee angle at toe-off, and knee flexion excursion during landing. The following kinetic data were analyzed: peak knee extension moments during countermovement and landing.FindingsACL-reconstructed individuals showed significant increases in knee flexion during countermovement and knee flexion excursion during landing from six weeks to six months after reconstruction but they remained significantly below the level of the controls. The reconstructed knee joint showed increased flexion at toe-off compared to the non-injured leg at all test sessions. Knee extension moments during countermovement increased up to six months after reconstruction, but remained deficient in ACL-reconstructed individuals during countermovement and landing compared to the controls.InterpretationAlthough ACL-reconstructed individuals showed increases in most kinematic and kinetic variables, they remained below the controls at six months post-ACL reconstruction. The deficits between contralateral legs and compared to the controls show that six months post-ACL reconstruction, knee joint functionality was still not equal between reconstructed and non-injured legs or in comparison to controls.     

前交叉韧带重建术后患者的等速肌力训练和疗效评定

目的:研究用Biodex system 3多关节等速肌力评定及训练系统对ACL重建术后患者肌力的影响。方法:将50例行ACL重建术后的患者随机分成试验组25例(等速训练患侧肌力)和对照组25例(等张训练患侧肌力)并分别进行功能训练,在术后第12、24周进行等速向心肌力测试。结果:术后第12、24周对患者进行膝关节等速向心肌力测试,试验组膝屈、伸肌患侧峰力矩/健侧峰力矩比值明显高于对照组,差异具有显著性(P<0.05),试验组在30°时的股内侧肌患侧峰力矩/健侧峰力矩比值明显高于对照组,差异具有显著性(P<0.05)。结论:通过等速训练进行系统的康复治疗可使膝关节ACL重建术后的患者短期(6个月)达到健侧屈伸肌力水平,并能达到运动水平。     

本体感觉训练在膝前交叉韧带重建术后康复中的应用

目的探讨本体感觉训练在前交叉韧带重建术后康复中的作用。方法将前交叉韧带重建术后患者42例按病区分为本体感觉促进组(26例)和对照组(16例),对照组应用一般康复训练方法,本体感觉促进组应用一般康复训练方法和本体感觉强化训练。术后6个月进行患者位置觉测定、膝关节功能评分及关节稳定性检查。结果在被动角度重现测试中,本体感觉促进组患侧膝的总平均偏差为(4.10±1.38)°,健侧膝的总平均偏差为(3.76±1.93)°,两侧膝比较,差异无统计学意义(P>0.05)。对照组患侧膝的总平均偏差为(4.85±1.55)°,健侧膝的总平均偏差为(3.56±1.72)°,患侧膝的总平均偏差显著大于健侧(P<0.01)。本体感觉促进组的Lysholm评分显著高于对照组(P<0.05)。2组患侧膝Lanchman和Pivotshift检查均为阴性。结论前交叉韧带重建术后应用强化本体感觉训练能促进下肢功能的恢复。     

Effects of knee bracing on the functional performance of patients with anterior cruciate ligament reconstruction

OBJECTIVE: To compare the functional performance of subjects with unilateral anterior cruciate ligament (ACL) reconstruction. DESIGN: Cross-sectional comparative clinical trial. SETTING: A physical therapy outpatient department. SUBJECTS: Thirty-one subjects with unilateral ACL reconstruction for more than 5 months. INTERVENTION: Patients under 3 bracing conditions: (1) DonJoy Brace, (2) mechanical placebo brace, or (3) no brace. Running and turning 10 times on a 22-meter figure-8 runway, and running and jumping (and landing) on a semicircular path. MAIN OUTCOME MEASURES: Speed of running and turning, speed of running and jumping, and accuracy of landing after the jump. RESULTS: Subjects performed similarly in conditions 1 and 2 in all the tests, but the speeds of running and turning were significantly slower in conditions 1 and 2 than condition 3 (p =.008--.000). Results of the run and jump tests were not different among all conditions. CONCLUSION: Knee bracing may not improve functional performance of subjects 5 months after ACL reconstruction. The use of such a brace could actually slow down running and turning, irrespective of the mechanical constraints of the brace. These functional outcomes need to be noted when such a brace is used on this group of subjects.     

Gait retraining after anterior cruciate ligament reconstruction

OBJECTIVES: To examine the effects of 2 gait retraining protocols on the gait patterns of patients with bone-patellar tendon-bone anterior cruciate ligament (ACL) reconstruction. DESIGN: Randomized control, repeated-measures design. SETTING: Private orthopedic center and research facility. PARTICIPANTS: Sixteen patients with bone-patellar tendon-bone ACL reconstruction, randomly subdivided into 2 groups (group 1, n=8; group 2, n=8), and a healthy control group of 8 subjects. INTERVENTION: The 16 subjects with ACL reconstruction were randomly assigned to 2 different gait retraining protocols over a 6-week training interval: (1). a protocol using a predicted stride frequency calculated from the resonant frequency of a force-driven harmonic oscillator (FDHO) model or (2). a protocol using the preferred stride frequency (PSF). MAIN OUTCOME MEASURES: Gait analyses examining the lower-extremity kinematic, kinetic, and energetic gait patterns of each group. RESULTS: Gait retraining with the FDHO model showed improvements in lower-extremity positions, hip and knee extensor angular impulse, and work parameters. Gait retraining with the PSF demonstrated no statistical improvements. The FDHO training protocol facilitated a greater midstance knee range of motion (ROM) and greater rates of improvement for midstance ROM, hip extensor angular impulse, and concentric hip extensor work. CONCLUSIONS: Gait retraining with the resonant frequency of an FDHO model facilitated a greater recovery of gait function compared with training with the PSF.     

适应膝关节肌力变化：是重建前交叉韧带后康复治疗的基本原则

背景：前交叉韧带重建后早期如何干预以减少肌力下降和切取腘绳肌腱后对屈膝肌电-机械延迟的影响是一个值得研究的方向。目的：采用文献分析法重点对前交叉韧带重建后膝关节肌力的变化及康复的进展进行了综述分析。方法：以＂Anterior Cruciate Ligament;hamstring;Muscle Strength＂和＂前交叉韧带;肌力;腘绳肌;电-机械延迟＂为中英文检索词,计算机检索2000年1月至2014年1月PubMed数据库及万方医学网相关文献。选择与前交叉韧带重建后肌力的改变、评价方法及重建后肌力康复相关的文献。最终纳入34篇文献进行探讨。结果与结论：研究表明：切取腘绳肌腱会导致术后的屈膝肌力和胫骨内旋肌力的降低,从而影响膝关节的稳定性和功能活动水平。综合临床和等速肌力测试的结果,可以对前交叉韧带重建后的疗效进行综合评定,H/Q比率（屈/伸比）的改变能够用于指导前交叉韧带损伤后的康复。前交叉韧带重建后移植物塑形过程比其他动物实验研究更长,肌腱松弛度是影响电机械延迟的重要因素之一。在基本康复训练原则的基础上根据个体功能水平及时做出相应的调整,充分体现个性化训练。国内外研究均表明前交叉韧带重建肌力康复始于重建手术之前,以尽早开始肌肉收缩的再训练从而最大程度地防止肌肉萎缩。存在的问题主要集中在康复手段的更细化和科学化以及早期康复训练的＂度＂的把握上。     

Association between knee function and kinesiophobia 6 months after anterior cruciate ligament reconstruction

[Purpose] Kinesiophobia after anterior cruciate ligament reconstruction has been identified as an inhibitor of return to sports. This study aimed to clarify the relationship between kinesiophobia and knee function 6 months after anterior cruciate ligament reconstruction when the patient intends to return to sports. [Participants and Methods] A total of 66 patients who underwent primary anterior cruciate ligament reconstruction (mean age 17.3 ± 2.6 years, 17 males and 49 females, Tegner activity score ≥7) were included in the study. The 11-item version of Tampa scale of kinesiophobia was used to evaluate kinesiophobia 6 months postoperatively. Knee function was evaluated with knee extension muscle strength, tibial anterior displacement, heel buttock distance, heel height difference, anterior knee pain score, and single-leg hop test. The relationship between Tampa scale of kinesiophobia, patient characteristics, and knee function was investigated. [Results] A low Anterior knee pain score and low single-leg hop test, male gender, and age were significant factors associated with kinesiophobia. [Conclusion] Kinesiophobia was associated with a low anterior knee pain score and low single-leg hop test 6 months after anterior cruciate ligament reconstruction. Patients with a low single-leg hop test score or severe pain may need rehabilitation to reduce kinesiophobia.     

Hop testing symmetry improves with time and while wearing a functional knee brace in anterior cruciate ligament reconstructed athletes

BackgroundThere is currently no consensus among orthopaedic surgeons as to when patients with anterior cruciate ligament reconstruction are ready to return to sport or whether or not patients should wear a functional knee brace during athletic activity. The purpose of the present study was to determine the effects of time since return to sport and of a functional knee brace on hop distance and loading symmetry during hop testing in patients with anterior cruciate ligament reconstruction.MethodsTwenty-eight patients with anterior cruciate ligament reconstruction completed hop testing after being released to return to sport and again 3 months later, both with and without wearing a custom fit extension constraint functional knee brace. The loadsol® captured plantar loading data (100 Hz) to quantify peak impact force, loading rate, and impulse during the final landing of every hop test. A limb symmetry index was calculated between surgical and non-surgical limbs for hop distance and loading measures.FindingsWearing a knee brace increased hop distance symmetry during the single and crossover hop tests and peak impact force symmetry on each test (all p < 0.05). While single (p = 0.022) and triple (p = 0.002) hop distance symmetry increased with time, there was no effect of time on any loading symmetry outcomes.InterpretationThese results support using a functional knee brace during athletic activities for improving symmetry in the early return to sport period. These results also support previous findings that while hop distance symmetry improves with time, asymmetrical landing mechanics do not and should be addressed clinically.