Toe-out angle changes after total knee arthroplasty in patients with varus knee osteoarthritis

Purpose

Toeing-out is a commonly proposed kinematic variable that has been suggested to reduce external knee adduction moment. Analyses of the toe-out angle after total knee arthroplasty (TKA) are useful for obtaining a proper understanding of the abnormal gait caused by varus knee osteoarthritis (OA), as well as performing rehabilitation after arthroplasty. Changes in the toe-out angle after arthroplasty have not yet been defined or analysed.

Methods

The study population consisted of 32 knees in 32 patients with varus knee OA who underwent TKA. The femorotibial angle was evaluated on standing anteroposterior radiographs before and after arthroplasty. The subjects underwent three-dimensional motion capture analyses to measure gait parameters (walking speed, cadence, stride length, step length, step width and the relative length of the single-limb support (SLS) percentage of one gait cycle) and the maximal hip adduction angle in the stance phase, the trunk lean angle in the coronal plane and the toe-out angle before and 4 weeks after arthroplasty.

Results

The femorotibial angle on the side of arthroplasty improved after surgery. Among the measured gait parameters, only the SLS percentage increased significantly. The hip adduction angle and toe-out angle on the side of arthroplasty increased significantly after surgery.

Conclusions

The knee alignment and hip adduction angle in the coronal plane and SLS phase were normalized after arthroplasty. The increase in the toe-out angle after arthroplasty may be attributable to the restoration of a normal knee alignment. These findings contribute to obtaining a proper understanding of the abnormal gait caused by varus knee OA and are useful for orthopaedic surgeons and rehabilitation therapists when treating patients after arthroplasty.

Level of evidence

Prospective study, Level II.     

膝骨关节炎患者平衡功能下降的影响因素分析

目的 明确膝骨关节炎(knee osteoarthritis,KOA)患者平衡功能下降的主要影响因素.方法 对89例KOA患者进行人口统计学基本信息采集、视觉模拟疼痛评分(visual analogue pain scale,VAS)、患膝关节的影像学分级、稳定极限测试(limits of stability,LOS)及双下肢的反应性测试、位置觉测试和等速肌力测试.结果 以年龄为控制因素,经Pearson偏相关分析发现患膝的VAS评分、反应时间、整体反应时间、复位误差平均值和60°峰力矩与LOS总分密切相关(P<0.05);经多元线性回归分析发现,患膝的复位误差平均值、60°伸肌峰力矩和反应时间是LOS总分的主要影响因素(P<0.01).结论 超重、膝关节疼痛、KOA病程、膝关节影像学分级不是导致KOA患者平衡功能下降的主要影响因素,而因膝关节疼痛导致的下肢肌力下降、本体感觉减退和患膝关节对新刺激做出知觉反应能力的减慢是导致KOA患者平衡功能较之无KOA者更差的疾病自身特征性主要影响因素.     

Measuring body weight distribution during sit-to-stand in patients with early knee osteoarthritis

People with severe degenerative conditions, such as osteoarthritis (OA), have been shown to have altered movement patterns during sit-to-stand. However it remains unclear whether such alterations exist in people with early OA, in the absence of pain. This study aimed to determine if a novel seat could be used to discriminate people with early OA compared with controls. The sit-to-stand task was performed by 20 people with early medial knee OA and 20 age and gender-matched control subjects, using an instrumented seat. OA subjects showed altered weight distribution in the transition phase from sit to stand, in that they placed more load through their unaffected side. Task duration was significantly longer for OA subjects, and ground reaction force integrals were significantly greater for both legs of OA subjects. OA subjects had significantly higher knee flexion and adduction moments in their unaffected compared with affected side. This study has demonstrated that a novel instrumented seat can be used to discriminate people with early medial knee OA during the sit-to-stand activity. These results may be relevant for early interventions to delay or prevent changes in muscle function of the affected limb as well as contralateral knee or hip osteoarthritis in these patients.     

阿伦磷酸钠联合高压氧治疗老年膝关节骨性关节炎的疗效观察

目的 观察阿伦磷酸钠联合高压氧治疗对老年膝关节骨性关节炎的疗效.方法 经患者知情同意,并签署知情同意书后,采用数字表法将82例老年膝关节骨性关节炎患者随机分为2组,每组41例,治疗组给予阿伦磷酸钠结合高压氧治疗,对照组患者仅给予阿伦磷酸钠治疗,2组患者均接受相同的康复指导锻炼,分别在治疗开始2、4、12和24周对其膝关节疼痛情况、股四头肌肌力60°/s等速肌力测试和主动屈伸膝活动度进行测试.结果 治疗后,治疗组NRS评分为1.8±0.3,对照组为2.9±0.9(P＜0.05);治疗组60°/s等速肌力测得值为(34.43±16.34)W,对照组为(27.43±13.54)W,(P＜0.05);治疗组主动屈伸膝活动度在治疗24周时为113.95±13.39、1.85±0.32,对照组为102.93±10.72、5.32±1.33(P ＜0.05).结论 阿伦磷酸钠联合高压氧治疗对老年膝关节骨性关节炎患者具有较好的治疗作用.     

Sensitivity to change and association of three-dimensional meniscal measures with radiographic joint space width loss in rapid clinical progression of knee osteoarthritis

Objective

To determine whether 3D meniscal measures had similar sensitivity to longitudinal change as cartilage thickness; to what extent these measures are associated with longitudinal joint space width (JSW) change; and whether the latter associations differ between minimum (mJSW) and fixed-location JSW.

Methods

Two-year changes in medial meniscal position and morphology, cartilage thickness (MRI) and minimum and fixed-location JSW (radiography) were determined in 35 Osteoarthritis Initiative knees [12 men, age: 67 (51-77) years; 23 women, age: 65 (54-78) years], progressing from baseline Kellgren-Lawrence grade ≤2 to knee replacement within 3-5 years. Multiple linear regression assessed the features contributing to JSW change.

Results

Meniscal measures, cartilage thickness and JSW displayed similar sensitivity to change (standardised response mean≤|0.76|). Meniscal changes were strongly associated with JSW change (r≤|0.66|), adding ≤20% to its variance in addition to cartilage thickness change. Fixed-location JSW change (multiple r²=72%) was more strongly related to cartilage and meniscal change than mJSW (61%). Meniscal morphology explained more of fixed-location JSW and meniscal position more of mJSW.

Conclusion

Meniscal measures provide independent information in explaining the variance of radiographic JSW change. Fixed-location JSW appears to be more reflective of structural change than mJSW and, hence, a potentially superior measure of structural progression.

Key Points

? 3D positional/morphological meniscal measures change in rapidly progressing knees. ? Similar sensitivity to 2-year change of quantitative meniscal/cartilage measures in rapid progression. ? Changes in meniscal measures are strongly associated with radiographic JSW change. ? Meniscal change provides information to explain JSW variance independent of cartilage. ? Fixed-location JSW reflects structural disease stage more closely than minimum JSW.

     

Relationship of 3D meniscal morphology and position with knee pain in subjects with knee osteoarthritis: a pilot study

Objectives  

To explore whether quantitative, three-dimensional measurements of meniscal position and size are associated with knee pain using a within-person, between-knee study design.     

膝关节骨性关节炎受试者半月板的三维形态及位置与膝关节疼痛之间的关系:一项试验研究

目的通过比较同一个人不同膝关节,来探讨半月板位置和大小的定量三维测量结果是否与膝疼痛有关。方法 53例病人(男19例,女34例)为骨关节炎初期,这些研究对象有同样的放射学骨关节炎分级,且患肢频繁疼痛而健肢     

Stride-to-stride variability of knee motion in patients with knee osteoarthritis

PURPOSE: Individuals with knee osteoarthritis (OA) experience pain, frontal plane joint laxity and instability. Co-contraction can control laxity and instability but may place constraints on the variability of the knee's motion during gait. Slight variation among gait cycles is normal, but reduced variability of joint motions could be detrimental. The purpose of this study was to quantify knee motion variability during gait and assess the influence of muscle activity, frontal plane laxity, and pain on knee movement variability in patients with medial knee OA. METHODS: Fifteen subjects with unilateral medial knee OA and 15 age and gender matched uninjured subjects underwent gait analysis, with electromyography to compute co-contraction. Stress radiographs were obtained for measuring frontal plane laxity. Knee motion variability was assessed from the phase angle (knee angle versus angular velocity) during early stance. RESULTS: Despite altered involved side knee kinematics and kinetics, individuals with knee OA showed involved side frontal plane variability which was not significantly different from the control group, but was significantly lower than the variability of the uninvolved knee's motion. Laxity and medial co-contraction influenced the amount of joint motion variability in the involved knee of the OA subjects. Pain did not influence variability. CONCLUSION: Patients with medial knee OA displayed altered involved knee kinematics and kinetics, although stride-to-stride variability of knee motion was unchanged. Evidence of excessive joint motion variability on the uninvolved side, however, may provide insight into the development of OA in the contralateral cognate joint.     

The relationship between muscle capacity utilization during gait and pain in people with symptomatic knee osteoarthritis

BackgroundMuscle capacity utilization reflects the percentage of maximal knee extensor strength required to complete physical activities.Research questionIs pain associated with muscle capacity utilization during walking in older adults with knee osteoarthritis? Secondarily, is muscle capacity utilization in older adults with knee osteoarthritis sex-specific?MethodsTwenty-three participants (15 females) with symptomatic knee OA completed this study [age 67 ( ± 8) years, body mass index 29.7 ( ± 3.9) kg/m², gait speed during the Six Minute Walk test 1.25 ( ± 0.25) m/s]. Pain was measured using the Knee injury and Osteoarthritis Outcome Score. Muscle capacity utilization was quantified as the peak external knee flexor moment during level walking normalized to knee extensor maximum voluntary isometric contraction. The knee flexor moment was calculated from kinematic and kinetic data during barefoot level walking at a self-selected speed and at 1.1 m/s. Knee extensor maximum voluntary isometric contraction was measured on a dynamometer. Multiple linear regressions were used to determine the relationship between pain and muscle capacity utilization after adjusting for age, sex, body mass index, and gait speed. Independent sample t-tests examined sex differences.ResultsPain was not associated with muscle capacity utilization during self-selected and standardized walking speeds (p = 0.38 and p = 0.36, respectively). Females did not require a greater muscle capacity utilization than males to complete gait at self-selected and standardized speeds (p = 0.28, and p = 0.40, respectively).SignificanceMuscle capacity utilization was not associated with pain during walking in people with knee osteoarthritis. Future work should explore more challenging activities of daily living in knee OA.     

Quantifying peri-meniscal synovitis and its relationship to meniscal pathology in osteoarthritis of the knee

The objectives of this study were to validate a semiquantitative scoring system for estimating perimeniscal synovitis in osteoarthritic (OA) knees and to examine the relationship between the extent of synovitis and the degree of meniscal pathology using gadolinium-enhanced magnetic resonance imaging (MRI). Forty-three subjects with clinically diagnosed OA knee were assessed for peri-meniscal synovitis using gadolinium-enhanced MRI. Quantitative measurements of synovitis were made by summing areas in consecutive slices within generated regions of interest, and the synovitis was also scored semi-quantitatively using a 0–3 scale. Meniscal pathology (extrusion, degeneration and tearing) was also scored semiquantitatively. Establishment of a correlative relationship was undertaken using Spearman’s rho (ρ). A total of 86 sites were assessed. The semi-quantitative synovitis score correlated well with the quantitative synovitis score (ρ>0.9). A moderate association between medial meniscal extrusion and synovitis was demonstrated (ρ=0.762, P<0.000), although this association was not as strong in the lateral compartment (ρ=0.524, P<0..000). The results suggest the semiquantitative scoring system is valid for assessing perimeniscal synovitis. The relationship between meniscal pathology and adjacent synovitis requires further study.     

Inexpensive footwear decreases joint loading in elderly women with knee osteoarthritis

Recent literature has highlighted that the flexibility of walking barefoot reduces overload in individuals with knee osteoarthritis (OA). As such, the aim of this study was to evaluate the effects of inexpensive, flexible, non-heeled footwear (Moleca^®) as compared with a modern heeled shoes and walking barefoot on the knee adduction moment (KAM) during gait in elderly women with and without knee OA. The gait of 45 elderly women between 60 and 70 years of age was evaluated. Twenty-one had knee OA graded 2 or 3 according to Kellgren and Lawrence's criteria, and 24 who had no OA comprised the control group (CG). The gait conditions were: barefoot, Moleca^®, and modern heeled shoes. Three-dimensional kinematics and ground reaction forces were measured to calculate KAM by inverse dynamics. For both groups, the Moleca^® provided peak KAM and KAM impulse similar to barefoot walking. For the OA group, the Moleca^® reduced KAM even more as compared to the barefoot condition during midstance. On the other hand, the modern heeled shoes increased this variable in both groups. Inexpensive, flexible, and non-heeled footwear provided loading on the knee joint similar to a barefoot gait and significant overload decreases in elderly women with and without knee OA, compared to modern heeled shoes. During midstance, the Moleca^® also allowed greater reduction in the knee joint loads as compared to barefoot gait in elderly women with knee OA, with the further advantage of providing external foot protection during gait.     

Tests for physical function of the elderly with knee and hip osteoarthritis

This study reports the results of a battery of physical function tests used to assess physical function of older patients with clinical knee and/or hip osteoarthritis (OA), and the correlation to the WOMAC Index (disease-specific questionnaire). A total of 106 sedentary subjects, aged >60 years (mean 69.4, S.D. 5.9) with hip and/or knee OA (mean 12.2 yrs, S.D. 11.0) participated in the study. Mobility, joint flexibility and muscle strength were evaluated by recording time to: walk a distance of 8', ascend/descend 4 stairs, rise from/sit down from a chair (5 times). Hip/knee flexion and isometric quadriceps strength were also measured. Categories of performance were formed by dividing data into quartiles for each test (1=highest, 4=lowest score, 5=unable to complete) and, by summing the category scores, a total summary score (TSS) was obtained. The battery of physical function tests showed an acceptable test-retest reliability (ICC of all tasks > or =0.80) and internal consistency (Cronbach's alpha > or =0.80). Performance scores on walking, stair climb, chair-rise and ROM of affected OA joints were significantly correlated with each other, and with the WOMAC Index (P<0.05, Spearman's correlation). Lower scores on the TSS were associated with lower scores on all the WOMAC Index items (P<0.001). This study shows that a simple battery of physical function tests in combination with the WOMAC Index are reliable and may be useful outcome measures in the evaluation of therapeutic interventions and geriatric rehabilitation.     

Clinical gait evaluation of patients with knee osteoarthritis

Knee osteoarthritis (KOA) is the most common osteoarthritis in lower limbs, and gait measurement is important to evaluate walking function of KOA patients before and after treatment. The third generation Intelligent Device for Energy Expenditure and Activity (IDEEA3) is a portable gait analysis system to evaluate gaits. This study is to evaluate the accuracy and reliability of IDEEA3 for gait measurement of KOA patients. Meanwhile, gait differences between KOA patients and healthy subjects are examined. Twelve healthy volunteers were recruited for measurement comparison of gait cycle (GC), cadence, step length, velocity and step counts between a motion analysis system and a high-speed camera (GoPro Hero3). Twenty-three KOA patients were recruited for measurement comparison of former five parameters between GoPro Hero3 and IDEEA3. Paired t-test, Concordance Correlation Coefficient (CCC) and Intraclass Correlation Coefficient (ICC) were used for data analysis. All p-values of paired t-tests for GC, cadence, step length and velocity were greater than 0.05 while all CCC and ICC results were above 0.95. The measurements of GC, cadence, step length, velocity and step counts by motion analysis system are highly consistent with the measurements by GoPro Hero3. The measurements of former parameters by GoPro Hero3 are not statistically different from the measurements by IDEEA3. IDEEA3 can be effectively used for the measurement of GC, cadence, step length, velocity and step counts in KOA patients. The KOA patients walk with longer GC, lower cadence, shorter step length and slower speed compared with healthy subjects in natural speed with flat shoes.     

Relationship between magnetic resonance imaging findings,radiological grading,psychological distress and pain in patients with symptomatic knee osteoarthritis

Background

Synovial hypertrophy, synovial effusions, and abnormalities in the subchondral bone play a key role in the pathogenesis of osteoarthritis (OA) and are associated with pain. Understanding and careful clinical assessment together with better imaging such as magnetic resonance imaging (MRI) of the knee may improve treatment strategies. The aim of this cross-sectional study was to investigate the associations between the structural findings on MRI (bone marrow lesions [BMLs], synovitis, cartilage defects, meniscal lesions), X-ray examination (Kellgren and Lawrence [K/L] grade), and psychological aspects with pain in patients with knee osteoarthritis (KOA).

Methods

In this study, patients with symptomatic KOA were included. Knee radiographs were acquired and scored according to the K/L score. MRI was performed with a 1.5 T whole-body scanner; the presence of the following alterations was collected: BMLs, infrapatellar fat pad (IFP) synovitis, condral defects, and meniscal tears. Knee pain was assessed with Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale. The Mental Component Summary Scale Score (MCS) of the Medical Outcomes Study Short-Form 36 Health Survey (SF-36) questionnaire was used to evaluate psychological impact.

Results

BMLs were detected in 57 (38.3%) subjects of 149 participants (aged 51–81 years, female 75.8%). Cartilage defects were found in 91.9% of patients, IFP synovitis in 37.5%, meniscal lesions in 34.9%. In multiple regression analyses, WOMAC knee pain was significantly associated with the volume of the BMLs (p = 0.0001), IFP synovitis (p = 0.0036), and SF-36 MCS (p = 0.0001), but not with K/L grades, meniscal lesion score, cartilage defect, sex, age, educational level, disease duration and BMI.

Conclusion

In symptomatic KOA patients, MRI features, such as larger BMLs, IFP synovitis, and high levels of psychological distress, are associated with greater knee pain. Confirmation of these findings in the prospective studies of KOA is needed.

     

Presumptive subarticular stress reactions of the knee: MRI detection and association with meniscal tear patterns

Objective MRI detects subchondral marrow findings in painful knees which bear resemblance to spontaneous osteonecrosis of the knee (SONK). Gathering evidence suggests that the primary or predominant pathogenesis of these lesions is physical stress. This study analyzes the patient characteristics and meniscal pathology associated with these lesions—herein referred to as presumptive subarticular stress related (PSSR) lesions.Design and patients All patients were scanned using a standardized imaging protocol. The criterion for a PSSR lesion was a subchondral marrow edema pattern encompassing a more focal, low-signal zone adjacent to or contiguous with the subchondral cortex. Patients were identified using an electronic database search of cases reported by one experienced musculoskeletal radiologist.Results Twenty-five PSSR lesions were identified among 1,948 MRI evaluations of the knee. Twenty-one PSSR lesions occurred in the medial compartment, and four occurred in the lateral compartment. There was no sex predilection. Patients with PSSR lesions were older than other patients undergoing MRI evaluation (mean 66 years versus 52 years, P<0.001). Meniscal tears occurred more commonly in cases with PSSR lesions than in the group as a whole (76% versus 45%, P<0.001). Radial and posterior root tears were more common in knees with PSSR lesions than in other knees with meniscal tears (53% versus 26%, P<0.01).Conclusions PSSR lesions are associated with meniscal tears and, more specifically, with meniscal tear patterns that dramatically increase contact forces across the knee joint. This observation supports the hypothesis that mechanical stress is important in the pathogenesis of these subarticular lesions that are detected by MRI.     

膝关节骨性关节炎的X线测量与分析

目的:通过对膝关节骨性关节炎患者X线片的测量,分析膝关节骨性关节炎患者股骨、胫骨和髌骨形态学改变,以及三者之间排列关系的改变,进而分析这些改变在膝关节骨性关节炎中的诊治意义和作用。方法:取正常组100例膝和膝关节骨性关节炎组127例膝,拍摄正位、侧位和髌骨轴位CR片,并对其分组逐一测量股骨角等指标,应用统计学方法对测量结果卡方检验,对检验结果进行分析,并结合临床进行讨论。结果:膝关节骨性关节炎组(KOA组)胫骨角等的检验结果与正常组存在差异,有统计学意义。而股骨角的检验结果与正常组间无差异。结论:①在膝关节骨性关节炎患者影像学分析中,出现了胫骨角等指标的变化。股骨角对于膝关节骨性关节炎的影像学分析不敏感。②在膝关节骨性关节炎患者影像学分析和统计学检验中,验证了膝内翻发生率高于膝外翻,股胫关节内侧间隙狭窄多于股胫关节外侧间隙狭窄。③在膝关节骨性关节炎患者X线分析中,发现髌股关节可出现髌骨外翻脱位。     

体外冲击波治疗中老年女性膝关节炎的疗效观察

 目的 观察体外冲击波治疗中老年女性膝关节炎的疗效。方法 将2014-08至2014-12收集到的65例女性膝关节炎患者随机分为两组,氨糖组给予硫酸氨基葡萄糖胶囊口服, 1～2粒(0.314～0.628 g)/次,连续服用8周。冲击波组给予冲击频率为7 Hz,能量1～2 bar的发散式体外冲击波治疗,每个部位冲击2000下,1次/周,8次为一疗程。对两组患者治疗前及治疗一疗程后行视觉模拟疼痛评分(visual analog scale,VAS),膝关节功能评分(Western Ontario and McMaster University Osteoarthritis Index,WOMAC)及测量50 m快速走时间。结果 两组患者均未见严重不良反应,体外冲击波组患者疼痛缓解,平均VAS疼痛评分(3.2±2.4)较治疗前(6.8±2.2)明显下降,差异有统计学意义(P<0.05)。膝关节功能WOMAC指数均较治疗前有改善(P<0.05)。 50 m快速走平均时间(37.0±6.3)s较治疗前(39.9±7.7)s明显缩短,差异有统计学意义(P<0.05)。对照组VAS疼痛评分,膝关节功能WOMAC指数,50 m快速走时间变化无明显统计学意义。结论 相对于口服氨基葡萄糖,体外冲击波疗法治疗中老年女性膝骨关节炎无不良反应,能缓解疼痛,恢复关节功能,可作为治疗骨关节炎的新选择。