髌股疼痛综合征患者股四头肌失衡程度评估及其与Q角的相关分析

目的:利用表面肌电图对髌股疼痛综合征(PFPS)患者股四头肌失衡程度进行评估,并对其与Q角的关系进行分析.方法:PFPS病例组及正常对照组各30人,分别进行Q角测量,同时在双足半蹲动作时检测股外侧肌(VL)及股内斜肌(VMO)表面肌电图(sEMG),分析股内、外侧肌时域指标,对Q角与VL/VMO肌电比值进行相关分析.结果:病例组VL、VMP时域指标ZCR、RMS、IEMG差异有统计学意义(P＜0.05),且VL较VMO高.Q角与VL/VMO肌电比值之间进行线性相关分析,Pearson相关系数为0.149(P＞ 0.05).结论:PFPS患者VL运动单位募集数量、活化程度要高于VMO.股四头肌失衡程度与Q角大小无明显相关.     

闭链与开链运动对髌股疼痛综合征股四头肌作用的表面肌电图研究

摘要 目的：利用表面肌电图(sEMG)对髌股疼痛综合征（patellofemoral pain syndrome, PFPS）患者双足半蹲伴或坐位伸膝动作下股四头肌进行评估,比较不同开链与闭链动作对股四头肌的作用差异。 方法：PFPS病例组及正常对照组各30例,分别在双足半蹲以及坐位伸膝动作时检测股外侧肌(vastus lateralis, VL)及股内斜肌（vastus medialis oblique, VMO）表面肌电图,分析时域、频域指标,比较其平衡关系。 结果：病例组双足半蹲动作与坐位伸膝动作时各肌电指标的VL/VMO比值在时域、频域指标均有显著性差异,在坐位单侧完全伸膝动作时VL/VMO肌电比值大于双足半蹲动作且>1。 结论：VL、VMO表面肌电指标在双足半蹲动作时较坐位单侧完全伸膝动作时更接近平衡,提示适当屈膝时的闭链运动能够更有选择性地激发VMO,这为PFPS的康复治疗的动作选择提供参考。     

双足半蹲伴髋内收对髌股疼痛综合征股内斜肌的强化作用

目的采用表面肌电图(sEMG)评估髌股疼痛综合征（PFPS）患者的股四头肌失衡程度,观察PFPS患者各种表面肌电的特征及变化规律,并探讨髋内收对股内斜肌的针对性强化作用机制。 方法将PFPS患者60例按随机数字表法分为病例组和对照组,每组患者30例,分别在双足半蹲伴或不伴髋内收动作时检测股外侧肌(VL)及股内斜肌（VMO）表面肌电图,分析股内、外侧肌时域指标,比较其平衡关系。 结果双足半蹲不伴髋内收动作时,病例组VL的均方根振幅（RMS）和积分肌电值（IEMG）分别为（103.31±44.54）μV和（8.02±3.45）μVs,分别与组内VMO RMS的（85.02±41.19）μV和IEMG的（6.72±3.20）μVs比较,差异均有统计学意义（P<0.05）。病例组不伴髋内收时VMO的RMS、IEMG与组内伴髋内收时VMO的RMS、IEMG比较,差异均有统计学意义（P<0.05）。 结论双足半蹲伴髋内收的动作可以优先强化VMO,使VL与VMO之间达到更好的平衡状态。     

髌股疼痛综合征患者神经肌电活动比率与Merchant匹配角的相关性

目的:研究应用肌电生物反馈仪测量的髌股疼痛综合征(PFPS)患者的神经肌电活动比率与CT测量PFPS患者的髌骨倾斜角、Merchant匹配角的相关关系。方法:本实验收集山西大医院髌股疼痛综合征患者32例(其中女22例,男10例),应用肌电生物反馈治疗仪评定神经肌电活动比率[股内侧斜肌(VMO)/股外侧斜肌(VL)],行膝关节CT检查,测量患者髌骨倾斜角和Merchant匹配角。患者经肌电生物反馈疗法治疗5周后再次测量上述3个数值,并对数据进行统计分析。结果:32例PFPS患者治疗前CT图像Merchant匹配角和治疗前VMO/VL基线值之间的相关系数为-0.470(P<0.05),为中度相关关系,治疗前CT图像Merchant匹配角和治疗前VMO/VL动态值之间的相关系数为-0.447(P<0.05),为中度相关关系;治疗后CT图像Merchant匹配角与治疗后VMO/VL基线值之间的相关系数为-0.51(P<0.05),为中度相关关系,治疗后CT图像Merchant匹配角与治疗后VMO/VL动态值之间的相关系数为-0.604(P<0.05),为中度相关关系。32例PFPS患者治疗前、后CT髌骨倾斜角与治疗前、后VMO/VL基线值和动态值之间均无相关关系(P>0.05)。结论:应用肌电生物反馈仪测得的神经肌电活动比率可以反映髌骨移位的程度,但不能反映髌骨倾斜的程度,可以间接作为PFPS的诊断和疗效评价指标之一。     

股内侧斜肌在髌股关节不稳中作用的影像学研究进展

髌股关节不稳在年轻人群中常见,诸多因素可致髌股关节不稳,其中动力因素中股内侧肌与股外侧肌协调性不一致是重要原因之一。髌股关节不稳会对肌肉生物力学及功能状态造成影响,进一步导致临床常见的髌股关节疼痛。利用影像学技术评估股内侧斜肌在髌股关节不稳中的功能变化及早期指导临床治疗是现阶段研究的热点。本文对股内侧斜肌在髌股关节不稳患者中的作用及相关影像学研究进展进行综述。     

髌股关节疼痛综合征患者手术前后表面肌电图的比较分析

目的:了解表面肌电图(s EMG)评定髌股疼痛综合征(PFPS)患者手术治疗前后股内侧肌(VM)和股外侧肌(VL)动态平衡的变化。方法:分别对PFPS患者6例手术前后和健康者10例行s EMG测试、视觉模拟评分法(VAS)疼痛和Lysholm膝关节功能评分。结果:健康人、PFPS术前和术后3组间平均振幅右VM∶VL比值分别为1.09±0.36、0.90±0.28和0.94±0.35,3组间的差异无显著性意义(P0.05);3组VM与VL达峰值时限的差值(ΔTBP)分别为-1.45±4.02、7.55±5.84和-1.82±2.93,差异有显著性意义(P0.01),PFPS者术后较术前明显改善(P0.01),恢复到健康人水平(P0.05)。PFPS者VAS术后1.60±0.91较术前3.09±1.14减小(P0.01),Lysholm评分术后71.27±16.52较术前54.82±17.50明显提高(P0.01)。结论:本研究s EMG标准化测试VM和VL的峰值时限,能敏感反映PFPS患者手术治疗前后髌骨在冠状面上动态平衡的变化。     

表面肌电仪对髌股疼痛综合征患者膝关节肌电活动的分析

目的利用表面肌电仪分析髌股疼痛综合征患者康复训练前后股内侧斜肌（VMO）和股外侧肌（VL）肌电活动的变化。方法26例髌股疼痛综合征患者随机分为神经肌电生物反馈训练组（A组）和单纯训练组（B组）各13例，均接受相同的家庭训练，但A组患者在神经肌电生物反馈仪配合下进行训练。所有患者在开始训练前和训练8周后，利用表面肌电仪对VMO和VL的神经肌肉电活动进行连续6h评定，同时对膝关节疼痛程度进行评定。结果治疗后，B组患者的VMO／VL神经肌电比率与治疗前比较差异无显著性意义（P〉0．05），而A组患者的VMO／VL神经肌电比率与治疗前比较差异有显著性意义（P〈0．05）。结论采用神经肌电生物反馈仪配合髌股疼痛综合征患者的康复训练可促进股内侧斜肌的募集。     

表面肌电图在评定髌股疼痛综合征患者髌骨动态稳定中的应用

目的利用自建表面肌电图的标准化测试分析髌股疼痛综合征（PFPS）患者股内侧肌（VM）与股外侧肌(VL)在控制髌骨运动中的变化特征。 方法选取PFPS患者7例（13个膝）作为病例组,另选健康志愿者10例（20个膝）作为对照组,并分别进行表面肌电图检查,测量蹲起运动VM和VL的平均波幅和峰值时限（TBP)。 结果PFPS组和对照组VM∶VL平均振幅比值分别为（0.97±0.31）和（1.09±0.36）,2组差异无统计学意义（P&rt;0.05）,2组下蹲时的平均比值（1.00±0.16）明显高于起立时的平均比值（0.83±0.15）（P<0.05）。在蹲起时PFPS组的TBPVM较TBPVL延迟（8.77%±5.12%）与对照组（-1.45%±4.02%）的比较有统计学意义（P<0.01）。 结论所用表面肌电图的标准化测试能发现本组PFPS患者下蹲时VM的峰值时限明显滞后于VL,可用于评定局部型PFPS患者术后或康复治疗前后的变化。     

臭氧注射联合髌骨活动康复治疗疗对老年髌股关节疼痛缓解及功能恢复的影响

目的探讨臭氧注射联合髌骨活动康复治疗对老年髌股关节疼痛缓解及功能恢复的影响。方法选择髌股关节疼痛伴功能障碍的病人60例,随机分为两组,单纯臭氧注射组(O组,n=30)和臭氧注射加髌骨活动康复治疗组(O-P组,n=30)。两组均按照试验设计和操作常规于病变膝关节腔内注入40μg/ml臭氧10 ml,每周1次共4次,O-P组注射后进行髌骨活动度手法康复项目治疗1次/d。观察指标:①X线K-L分级评分;②VAS疼痛评分(通常痛和最痛评分);③kujala髌股关节功能评分。结果①不同治疗组组内比较,治疗后均显示较治疗前VAS疼痛评分分值降低,髌股关节功能评分分值升高(P<0.05);②髌骨关节X线分级中Ⅰ～Ⅱ级不同治疗组治疗后组间比较显示:两组VAS疼痛评分分值降低程度和髌股关节功能评分分值升高程度不具有相关性(P>0.05)。③髌骨关节X线分级中Ⅲ级和Ⅳ级的不同治疗组治疗后结果组间比较显示:O-P组的VAS疼痛评分分值的降低明显低于O组(P<0.05),髌股关节功能评分分值明显高于O组(P<0.05)。结论应用臭氧注射结合髌骨活动性康复治疗较单纯臭氧注射治疗可以更有效地缓解老年髌股关节疼痛,恢复退行性髌骨关节功能。     

从生物力学角度探讨髌股关节炎的病因

髌股关节炎是膝骨关节炎的一种类型,是造成膝前疼痛的重要原因之一。了解髌股关节炎的病因及发病机制对于预防、治疗髌股关节炎,防止其进展为膝骨关节炎具有重要意义。本文查阅了中外相关文献,旨在阐述髌股关节解剖结构与运动生理学特点,从髌骨位置、股骨滑车、Q角、髂胫束、内侧髌股韧带等静力结构异常和肌肉力量与协调性、膝周肌肉协同收缩率等动力结构异常方面进行综述,以期为髌股关节炎的康复治疗提供理论依据。     

Physical Examination and Patellofemoral Pain Syndrome: an Updated Review

Purpose of ReviewPatellofemoral pain syndrome (PFPS) accounts for 25 to 40% of all knee disorders. Diagnosis of PFPS is primarily based on history and physical examination, but the findings on physical examination are often subtle and do not consistently correlate with symptoms described. Yoon and Fredericson published a review article in 2006 detailing the physical examination maneuvers most frequently used to assist clinicians in the accurate diagnosis and treatment of PFPS, and our aim in this review is to provide an update on this previous article focusing on the literature published over the past 15 years regarding the topic.Recent FindingsSince publication of Fredericson’s original review article, there have been studies building on the literature specifically surrounding Q angle, patellar tilt, crepitus, strength and functional testing, and physical examination maneuver clustering. Additionally, multiple studies have been conducted on the use of musculoskeletal ultrasound (US) as a diagnostic tool for PFPS.SummaryRecent literature has further supported Q angle (when measured utilizing a standardized protocol), crepitus, weakness of hip abductors and extensors, and weakness detected in functional testing as predictors of PFPS while finding inconsistent evidence behind lateral patellar tilt as a predictor of PFPS. The reliability of most physical examination tests alone remain low, but clustering physical examination findings may provide better sensitivities and specificities in diagnosing PFPS. Musculoskeletal US is rapidly gaining popularity, and decreased vastus medialis obliquus (VMO) volume, asymmetry in gluteus medius thickness, intra-articular effusions, and quadriceps and patellar tendon thicknesses have shown value in diagnosing those with PFPS. Additionally, US has the advantage of providing dynamic examination as well as evaluation of the patellofemoral joint in newborns and infants as a predictor of future patellofemoral instability. Further studies are needed to establish the gold standard for diagnosing PFPS and what US findings are truly predictive of PFPS.     

Outcomes of a weight-bearing rehabilitation program for patients diagnosed with patellofemoral pain syndrome

OBJECTIVE: To determine the effects of a weight-bearing rehabilitation program on quadriceps and gluteus medius electromyographic activity, pain, and function in subjects diagnosed with patellofemoral pain syndrome (PFPS). DESIGN: Pretest and posttest 6-week intervention study. SETTING: Musculoskeletal research laboratory. PARTICIPANTS: Fourteen subjects diagnosed with PFPS and 14 healthy control subjects volunteered to participate in this study. No subjects withdrew from the study because of adverse effects. INTERVENTION: Subjects diagnosed with PFPS participated in a 6-week rehabilitation program. The rehabilitation program consisted of weight-bearing exercises that focused on strengthening the quadriceps and hip abductor musculature. MAIN OUTCOME MEASURES: Electromyographic onsets of the vastus medialis oblique (VMO) and vastus lateralis and onset and duration of the gluteus medius were collected during a stair-stepping task that was performed during the pretest and posttest. A visual analog scale (VAS) and Functional Index Questionnaire (FIQ) were administered at pretest and posttest and each week of the intervention. RESULTS: Vastus lateralis and VMO onset timing differences (vastus lateralis electromyographic onset minus VMO electromyographic onset) and VAS and FIQ scores significantly improved for patients diagnosed with PFPS. Vastus lateralis and VMO onset timing in the PFPS group were significantly different from those in the control group at baseline and were not significantly different from the control group after the intervention. We did not find differences in gluteus medius onsets or duration of activity. CONCLUSIONS: Subjects diagnosed with PFPS responded favorably and quickly to a therapeutic exercise program that incorporated quadriceps and hip musculature strengthening. The efficacy of the therapeutic exercise program used in this study should be further investigated in a larger subject population.     

Altered vastii recruitment when people with patellofemoral pain syndrome complete a postural task

OBJECTIVE: To investigate the recruitment of the vastus medialis obliquus (VMO) and vastus lateralis during voluntary tasks that challenge the stability of the knee and to evaluate whether there is a change in the coordination of the postural response by the central nervous system in subjects with patellofemoral pain syndrome (PFPS). DESIGN: Cross-sectional. SETTING: University laboratory in Australia. PARTICIPANTS: Thirty-seven subjects with PFPS and 37 asymptomatic sex-matched controls. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Recordings of electromyographic activity of the VMO, vastus lateralis, tibialis anterior, and soleus were made by using surface electrodes. Subjects rose onto their toes (rise task) or rocked back on their heels (rock task) in a visual choice-reaction time task. Electromyographic onsets were determined by using a computer algorithm and were verified visually. RESULTS: Our results confirm that, in asymptomatic subjects, contraction of the VMO and vastus lateralis occurs as part of the feed-forward postural response associated with ankle movements in standing, and the contraction of these separate heads of the quadriceps group occurs simultaneously. However, when subjects with PFPS perform identical tasks, the electromyographic onset of the vastus lateralis occurs before that of the VMO. CONCLUSION: These findings indicate a difference in motor control in subjects with PFPS. They also support the hypothesized relation between changes in the timing of activity of the vastii and PFPS and provide the theoretic rationale to support physiotherapy treatment commonly used in the management of PFPS.     

Vastus medialis obliquus and vastus lateralis activity in open and closed kinetic chain exercises in patients with patellofemoral pain syndrome: an electromyographic study

OBJECTIVES: To evaluate the electromyographic activities of vastus medialis obliquus (VMO) and vastus lateralis (VL) muscles in open and closed kinetic chain exercises in subjects with patellofemoral pain syndrome (PFPS). DESIGN: Case-controlled study. SETTING: Rehabilitation science center in a tertiary medical center. PARTICIPANTS: Ten patients with bilateral knee pain diagnosed with PFPS and 10 healthy volunteers. INTERVENTIONS: Subjects performed open kinetic chain exercise on an isokinetic dynamometer and closed kinetic chain exercise by squat-to-stand and stand-to-squat tasks. Surface electromyography was done for the VMO and VL muscles. MAIN OUTCOME MEASURES: VMO/VL ratios were calculated after normalization of muscle activities. RESULTS: The VMO/VL ratios of PFPS subjects were significantly lower than were those of unimpaired subjects during knee isokinetic closed kinetic chain exercises (p = .047). However, there was no statistical difference in VMO/VL ratio between subjects with and without PFPS during closed kinetic chain exercises (p = .623). Maximum VMO/VL ratio was obtained at 60 degrees knee flexion in closed kinetic chain exercise. CONCLUSION: In closed kinetic chain exercises, more selective VMO activation can be obtained at 60 degrees knee flexion. Maximal VMO/VL ratio was observed at this knee flexion angle, and muscle contraction intensity was also greatest.     

Effects of vision and cognitive load on static postural control in subjects with and without patellofemoral pain syndrome

Objective: To compare the effects of vision and cognitive load on static postural control in subjects with and without patellofemoral pain syndrome (PFPS). Methods: Twenty-eight PFPS patients and 28 controls participated in the study. Postural control was assessed in isolation as well as with visual manipulation and cognitive loading on symptomatic limb. The outcome measures of postural control were quantified in terms of area, anterior-posterior (AP), medial-lateral (ML), and mean velocity (MV) of the displacements of center of pressure (COP). In addition, cognitive performance (auditory Stroop task) was measured in the forms of average reaction time and error ratio in baseline (sitting) and different postural conditions. Results: PFPS subjects showed greater increases in area (p = 0.01), AP (p = 0.01), and ML (p = 0.05) displacements of COP in the blindfolded tasks as compared to control group. However, cognitive load did not differently affect postural control in the two groups. Although PFPS and control group had similar reaction times in the sitting position (p = 0.29), PFPS subjects had longer reaction times than healthy subjects in dual task conditions (p = 0.04). Conclusion: Visual inputs seem to be essential for discriminating postural control between PFPS and healthy individuals. PFPS patients biased toward decreasing cognitive performance more than healthy subjects when they perform the single leg stance and cognitive task concurrently.     

Electromyographic fatigue characteristics of the quadriceps in patellofemoral pain syndrome

This study compared the fatigue characteristics of the vastus medialis oblique (VMO), vastus lateralis (VL) and rectus femoris (RF) muscles. Ten healthy subjects with 10 patients with patellofemoral pain syndrome (PFPS) performed an isometric leg press for 60 seconds at 60% MVIC with data collected using surface EMG. The power spectrum was analyzed and the extracted median frequency normalised to calculate a linear regression slope for each muscle. A repeated measures ANOVA revealed no significant differences, neither between the groups (P=0.592) nor the muscles (P=0.434). However, the slopes for the VMO and VL were different between the two groups with similar slopes for the RF. There was much larger variability of MF values in the PFPS group. The VMO:VL ratio calculated from these slopes for the healthy subjects was 1.17 and for the PFPS group was 1.78. These results may indicate unusual features in the fatigue indices of the quadriceps in PFPS.     

Delayed onset of electromyographic activity of vastus medialis obliquus relative to vastus lateralis in subjects with patellofemoral pain syndrome

OBJECTIVE: To determine whether electromyographic (EMG) onsets of vastus medialis obliquus (VMO) and vastus lateralis (VL) are altered in the presence of patellofemoral pain syndrome (PFPS) during the functional task of stair stepping. DESIGN: Cross-sectional. SETTING: University laboratory. PATIENTS: Thirty-three subjects with PFPS and 33 asymptomatic controls. INTERVENTIONS: Subjects ascended and descended a set of stairs-2 steps, each 20-cm high-at usual stair-stepping pace. EMG readings of VMO and VL taken on middle stair during step up (concentric contraction) and step down (eccentric contraction). MAIN OUTCOME MEASURES: Relative difference in onset of surface EMG activity of VMO compared with VL during a stair-stepping task. EMG onsets were determined by using a computer algorithm and were verified visually. RESULTS: In the PFPS population, the EMG onset of VL occurred before that of VMO in both the step up and step down phases of the stair-stepping task (p <.05). In contrast, no such differences occurred in the onsets of EMG activity of VMO and VL in either phase of the task for the control subjects. CONCLUSION: This finding supports the hypothesized relationship between changes in the timing of activity of the vastimuscles and PFPS. This finding provides theoretical rationale to support physiotherapy treatment commonly used in the management of PFPS.     

Disability in patients with chronic patellofemoral pain syndrome: a randomised controlled trial of VMO selective training versus general quadriceps strengthening

This study was a prospective single blind randomised controlled trial to compare the effects of rehabilitation with emphasis on retraining the vastus medialis (VMO) component of the quadriceps femoris muscle and rehabilitation with emphasis on general strengthening of the quadriceps femoris muscles on pain, function and Quality of Life in patients with patellofemoral pain syndrome (PFPS). Patients with PFPS (n=69) were recruited from a hospital orthopaedic clinic and randomised into three groups: (1) physiotherapy with emphasis on selectively retraining the VMO (Selective); (2) physiotherapy with emphasis on general strengthening of the quadriceps femoris muscles (General); and (3) a no-treatment control group (Control). The three groups were then compared before and after an eight-week rehabilitation period. The Selective and General groups demonstrated statistically significant and 'moderate' to 'large' effect size reductions in pain when compared to the Control group. Both the Selective and General groups displayed statistically significant and 'moderate' and 'large' effect size improvements in subjective function and Quality of Life compared to the Control group. Knee flexion excursion during the stance phase of gait, demonstrated that there were no statistical significant differences and only 'trivial' to 'small' effect size differences between the Selective or General groups and the Control group. A large number of PFPS patients can experience significant improvements in pain, function and Quality of Life, at least in the short term, with quadriceps femoris rehabilitation, with or without emphasis on selective activation of the VMO component. Both approaches would seem acceptable for rehabilitating patients with PFPS. It may be appropriate to undertake exercises involving selective activation of the vastus medialis early in the rehabilitation process, however, clinicians should not overly focus on selective activation before progressing rehabilitation, especially in more chronic cases with significant participation restrictions.