膝骨关节炎患者股内侧肌、股直肌和股外侧肌间的协调性

目的应用表面肌电图和等速肌力测定方法比较膝骨关节炎患者与正常人股内侧肌、股直肌和股外侧肌间的协调性改变。方法34例膝骨关节炎患者和34名膝关节健康者在膝关节屈曲10°、60°、100°等长伸膝和等速60°/s、180°/s伸膝运动测试模式下,进行股内侧肌(VM)、股直肌(RF)和股外侧肌(VL)的表面肌电图和股四头肌肌力的评测,包括肌肉激活启动顺序和VM/VL神经肌电比值。结果与正常人对比,膝骨关节炎患者在等速180°/s伸膝运动时VM相对于VL启动延迟（P＜0.05）;在膝屈10°等长伸膝运动时,VM/VL神经肌电比值降低（P＜0.05）。结论膝骨关节炎患者患侧股四头肌的协调性减退。     

Relationship between knee alignment and the electromyographic activity of quadriceps muscles in patients with knee osteoarthritis

[Purpose] We evaluated the relationship between knee alignment and the electromyographic (EMG) activity of the vastus medialis (VM) to the vastus lateralis (VL) muscles in patients with knee osteoarthritis (OA) in a cross-sectional study. [Subjects and Methods] Forty subjects with knee OA were assessed by anatomic radiographic knee alignment and the VM/VL ratio was calculated. Surface EMG from both the VM and VL muscles were evaluated during maximal isometric contraction at 60° knee flexion. Simultaneously, peak quadriceps torque was assessed using an isokinetic dynamometer. Subjects were categorized into low, moderate, and high varus groups according to knee malalignment. The peak quadriceps torque and VM/VL ratio across groups, and their relationships with varus malalignment were analyzed. [Results] All subjects had medial compartment OA and the VM/VL ratio of all subjects was 1.31 ± 0.28 (mean ± SD). There were no significant differences in the peak quadriceps torque or VM/VL ratios across the groups nor were there any significant relationships with varus malalignment. [Conclusion] The VM/VL ratio and peak quadriceps torque were not associated with the severity of knee varus malalignment.Key words: Malalignment, Knee, Quadriceps     

An open label pilot investigation of the efficacy of Botulinum toxin type A [Dysport] injection in the rehabilitation of chronic anterior knee pain

Purpose. To examine the effect of intramuscular injection of botulinum toxin type A [Dysport®] to reduce relative overactivity of the vastus lateralis [VL] muscle, in conjunction with re-training of vastus medialis [VM] muscle as an adjunct to rehabilitation for chronic anterior knee pain.

Method. Eight females with chronic (>6 months) history of anterior knee pain, who had failed conservative management, were studied in this open label pilot study. Intramuscular Dysport® injection [300 – 500 units] to the distal third of VL muscle was followed by a 12-week customized home exercise programme to improve recruitment of VM muscle and functional knee control. VL and VM muscle cross sectional area from a standardized spiral CT sequence, isometric quadriceps strength (dynamometry), timed stair task, self-reported pain and disability were assessed.

Results. Subjects reported reduced knee pain and brace dependency and increased participation in sporting and daily living activities. Isometric quadriceps muscle strength was maintained or improved despite significant atrophy, evident on CT, of the distal component of VL in the treated limb. Time taken to ascend and descend a flight of stairs improved in all subjects. Subjective and objective improvements were maintained at 24-week follow-up.

Conclusions. These pilot data provide preliminary support for the role of Dysport® as an adjunct to non-surgical management of individuals with chronic anterior knee pain. Larger double blind, randomized, placebo-injection controlled studies of this novel approach to improving patellofemoral mechanics are needed to establish the efficacy of this intervention.     

An open label pilot investigation of the efficacy of Botulinum toxin type A [Dysport] injection in the rehabilitation of chronic anterior knee pain

PURPOSE: To examine the effect of intramuscular injection of botulinum toxin type A [Dysport] to reduce relative overactivity of the vastus lateralis [VL] muscle, in conjunction with re-training of vastus medialis [VM] muscle as an adjunct to rehabilitation for chronic anterior knee pain. METHOD: Eight females with chronic (>6 months) history of anterior knee pain, who had failed conservative management, were studied in this open label pilot study. Intramuscular Dysport injection [300 - 500 units] to the distal third of VL muscle was followed by a 12-week customized home exercise programme to improve recruitment of VM muscle and functional knee control. VL and VM muscle cross sectional area from a standardized spiral CT sequence, isometric quadriceps strength (dynamometry), timed stair task, self-reported pain and disability were assessed. RESULTS: Subjects reported reduced knee pain and brace dependency and increased participation in sporting and daily living activities. Isometric quadriceps muscle strength was maintained or improved despite significant atrophy, evident on CT, of the distal component of VL in the treated limb. Time taken to ascend and descend a flight of stairs improved in all subjects. Subjective and objective improvements were maintained at 24-week follow-up. CONCLUSIONS: These pilot data provide preliminary support for the role of Dysport as an adjunct to non-surgical management of individuals with chronic anterior knee pain. Larger double blind, randomized, placebo-injection controlled studies of this novel approach to improving patellofemoral mechanics are needed to establish the efficacy of this intervention.     

The association between muscle EMG and perfusion in knee extensor muscles

The relationships between electromyographic (EMG) activity and force as well as muscle blood flow and work have been well established. However, the association between muscle blood flow and EMG activity remains unsolved. Thus, to test the hypothesis that muscle EMG activity relates to muscle perfusion in different compartments of the quadriceps femoris (QF) muscle, 12 healthy male subjects were studied. During two very submaximal exercise bouts, at different exercise intensities, oxygen labelled radiowater and positron emission tomography were used to measure muscle perfusion. In addition, produced force of knee extensors and muscle EMG activity in the vastus lateralis (VL), vastus medialis (VM) and rectus femoris (RF) muscles were recorded during both exercise bouts. Although the exercise intensity and average force production was higher during the second exercise bout (38 +/- 15 versus 51 +/- 17 N; P = 0.007), the mean EMG activity was lower (RF; P<0.001) or unchanged (VL; P = 0.722 and VM; P = 0.640). During the second exercise period, perfusion also remained unchanged in the entire QF muscle (P = 0.223) and in its separate muscles (VL, P = 0.703; VM, P = 0.141; RF, P = 0.113) in a group level. However, the individual changes in muscle perfusion were tightly related to changes in muscle EMG activity in VL (r = 0.84; P = 0.002) and VM (r = 0.68; P = 0.015) but poorly in the RF muscle (r = 0.40; P = 0.257). In conclusion, the different associations between muscle perfusion and EMG activity in different QF muscles suggests specific functional role of the vasti muscles and the RF muscle.     

The Effects of Closed Kinetic Chain Exercises and Open Kinetic Chain Exercises Using Elastic Bands on Electromyographic Activity in Degenerative Gonarthritis

[Purpose] The purpose of this study was to examine the effects of closed kinetic chain exercises (CKCEs) and open kinetic chain exercises (OKCEs) with elastic bands on the electromyographic activity of patients with degenerative gonarthritis. [Subjects] The study subjects were 30 degenerative gonarthritis patients who were divided into a CKCE group (CKCEG, n=10), an OKCE group (OKCEG, n=10), and a control group (CG, n=10). [Methods] The CKCEG and the OKCEG performed exercises with elastic bands, and the CG took part in a quadriceps strengthening exercise. All three groups performed the exercises three times per week for four weeks. The electromyographic activities of the subjects’ vastus medialis (VM), rectus femoris (RF), vastus lateralis (VL), semitendinosus (ST), and biceps femoris (BF) muscles were measured and compared. [Results] Within-group comparisons revealed that the electromyographic activities of the VM, RF, VL, ST, and BF muscles increased significantly in the CKCEG. The OKCEG displayed significant increases in the electromyographic activity of the VM, RF, ST, and BF muscles, and the CG showed significant increases in the electromyographic activities of the RF, VL, ST, and BF muscles. In between-group comparisons after the intervention, the electromyographic activities of the VM, RF, and VL muscles of the CKCEG were significantly higher than those of the CG. The electromyographic activities of the VM, RF, and ST muscles of the OKCEG were significantly higher than those of the CG. [Conclusion] We consider CKCEs with elastic bands are an effective intervention for increasing the electromyographic activities of the VM, RF, VL, ST, and BF muscles of degenerative gonarthritis patients, and OKCEs with elastic bands are an effective intervention for increasing the electromyographic activities of the VM, RF, ST, and BF muscles of degenerative gonarthritis patients.     

Effectiveness of electric stimulation of the vastus medialis muscle in the rehabilitation of patients after total knee arthroplasty

OBJECTIVE: To investigate the possible effect of electric muscle stimulation (EMS) of the vastus medialis on the walking speed, Hospital for Special Surgery (HSS) knee score, and Physiological Cost Index (PCI) of patients during rehabilitation after total knee arthroplasty (TKA). DESIGN: Prospective, randomized controlled trial. SETTING: Various departments at a district general hospital in the United Kingdom. PARTICIPANTS: Thirty patients with unilateral osteoarthritis of the knee admitted for elective TKA were randomly assigned to 1 of 2 groups (15 per group): control and treatment. Both groups received standard physical therapy. The treatment group also received EMS of the vastus medialis. INTERVENTION: EMS (40Hz, 300micros) of the vastus medialis muscle for 4 hours a day, starting on postoperative day 2, over the first 6 postoperative weeks. MAIN OUTCOME MEASURES: Changes in walking speed, HSS knee score, and effort of walking as measured by the PCI. RESULTS: A statistically significant increase in walking speed was observed in the treatment group in relation to the control group at both 6 weeks (P=.0002) and 12 weeks (P<.0001) postoperatively. No statistically significant difference was observed in relation to the PCI or the HSS knee score variables. CONCLUSIONS: Application of EMS after TKA resulted in a statistically significant improvement in patients' walking speed. There was also a carry-over effect after the discontinuation of treatment.     

Neuromuscular and architectural alterations of the vastus lateralis muscle in elderly patients with unilateral knee osteoarthritis]

AIM: The aim of this study was to determine the mechanisms involved in muscle weakness in elderly patients with unilateral knee osteoarthritis. SUBJECTS: We investigated 7 patients with unilateral knee osteoarthritis. METHOD: We measured knee position sense and isometric maximal voluntary contraction (MVC) of the knee extensors. Electromyographic (EMG) measurement of biceps femoris (BF), rectus femoris (RF), vastus lateralis (VL) and vastus medialis (VM) involved different levels of contraction (25, 50, 75 and 100% MVC). Neuromuscular efficiency of quadriceps was also calculated (MVC/EMG). Ultrasonography was used to investigate the VL architectural parameters at the median part of the VL for different levels of contraction (25, 50, and 75% MVC). All tests were performed on the osteoarthritic and healthy knees. RESULTS: The quadriceps MVC of the affected knee was reduced by 30%. The VL thickness of the affected knee was 10% smaller than that of the unaffected knee. VL activity seen on EMG did not differ between knees, but RF, VM and BF activity was greater in the unaffected than affected knee. Neuromuscular efficiency was higher (26%) in the unaffected knee. Knee position sense was reduced by 33% in the affected knee. CONCLUSION: Quadriceps weakness associated with knee osteoarthritis seems to be related to changes in muscle rather than pennation angle and changes in fascicule length.     

Effects of Swedish massage on gait spatiotemporal parameters in adult women with medial knee osteoarthritis: A randomized controlled trial

BackgroundPatients with knee osteoarthritis (OA) are always faced with functional limitations in daily activities due to knee pain. They are also at risk of falling because of compensatory kinetics and kinematics changes in walking, which is why they are seeking complementary therapies to deal with their problems.ObjectiveThe present research aimed to evaluate whether Swedish massage is effective in relieving the symptoms of knee OA and improving the gait spatiotemporal parameters of patients with knee OA.MethodsThirty adult women with knee OA participated in this study voluntarily. The intervention group (n = 15) received Swedish massage on their quadriceps for 20–30 min per session (12 sessions). During this period, the control group (n = 15) received their regular treatment. Osteoarthritis symptoms were evaluated by the Western Ontario and McMaster Universities Osteoarthritis Index. The spatiotemporal parameters of gait were also captured by the motion analysis system during barefoot walking.ResultsThe intervention group demonstrated significantly more pain relief and improved function compared to the control group. A significant increase was observed in the gait speed, total support time, and single support time (P < 0.05). Moreover, there was a significant decrease in the step width and initial double support time of the patients after receiving Swedish massage (P < 0.05).ConclusionIt can be concluded that Swedish massage may positively affect pain relief and function improvement in patients with knee OA. Also, Swedish massage was found to improve the spatiotemporal parameters in the patients. This may have important clinical implications regarding the rehabilitation of patients with knee OA.     

Activation of vastus medialis oblique is not delayed in patients with osteoarthritis of the knee compared to asymptomatic participants during open kinetic chain activities

This study investigated whether the onset of electromyographic (EMG) activity of vastus medialis oblique (VMO) was delayed relative to that of vastus lateralis (VL) in patients with osteoarthritis (OA) of the knee compared to asymptomatic participants during open kinetic chain activities. An exploratory observational cross sectional study was carried out. Two groups were tested, symptomatic OA knee patients, diagnosed by an orthopaedic surgeon, (n=17), mean (SD) age 66.0 (7.6) years, and asymptomatic participants (n=17), 56.7 (8.6) years. Surface EMG activity of VMO and VL was measured, during concentric contractions extending the knee from 90 degrees flexion, and during maximal voluntary isometric contractions at 60 degrees knee flexion. The EMG onset times of VMO and VL were determined visually and by algorithm. The onset timing difference (OTD) between the two muscles was calculated for each subject, by subtracting the onset time of VL from VMO. Mann-Whitney U-tests revealed that the OTD between VMO and VL was not significantly different between the groups during either contraction type (both p>0.05). The results of this exploratory study may have implications for rehabilitation programmes aimed at developing preferential activation of VMO compared to VL in OA knee patients.     

实时剪切波超声弹性成像技术评估肌肉减少症患者骨骼肌弹性模量的研究

摘 要 目的 研究肌肉减少症患者股四头肌、腘绳肌和肱二头肌长轴剪切波速度（SWV）值特征,探讨实时剪切波超声弹性成像技术（SWE）评估肌肉减少症患者肌肉状态的应用价值。方法 选择22例肌肉减少症患者（病变组）和21例同期年龄、性别匹配的健康体检者（对照组）,应用剪切波超声弹性成像技术,获取病变组和对照组优势侧的股四头肌4块肌肉［股外侧肌（VL）,股直肌（RF）,股内侧肌（VM）和股中间肌（VI）］,腘绳肌3块肌肉［股二头肌（BF）,半腱肌（ST）和半膜肌（SM）］和肱二头肌（BB）松弛状态下长轴SWV值,并进行对比分析。结果 松弛状态下病变组与对照组的VL、RF、VM、VI、BF、ST、SM和BB肌肉的SWV数值差异有显著统计学意义(均P＜0.001)。松弛状态下病变组与对照组比较,VL、RF、VM、VI、BF、ST、SM和BB肌肉的SWV数值分别降低7.8%、7.0%、7.3%、7.3%、7.1%、7.3%、6.5%和6.7%。与对照组比较,病变组SM长轴的SWV值降低最小,VL长轴的SWV值降低最为显著。年龄和BMI指数均为老年人骨骼肌弹性模量的影响因素。结论 实时剪切波超声弹性成像技术可检测肌肉减少症患者较大骨骼肌弹性差异,为评估肌肉减少症患者肌肉状态提供了一种新的检测方法。     

Factors related to the indecision of older adults with knee osteoarthritis about receiving physician-recommended total knee arthroplasty

Purpose: To explore factors related to the indecision of older adults with knee osteoarthritis (OA) about receiving physician-recommended total knee arthroplasty (TKA) and their needs during the decision-making process.

Method: Older outpatients with knee OA and undecided about physician-recommended TKA (N?=?26) were recruited by convenience from two medical centers and one regional hospital in northern Taiwan. Data were collected in individual interviews using a semi-structured guide and analyzed by thematic analysis.

Results: Participants’ indecision about receiving physician-recommended TKA was due to four major concerns: treatment-related concerns, physical condition-related concerns, surgery-related concerns, and postsurgical care concerns. The few participants (n?=?6) who expressed needs during the decision-making process wanted more information about preparing for surgery, postsurgical care, rehabilitation, and medicines.

Conclusions: Healthcare providers are challenged to respect the decision-making process of older adults with OA regarding recommended TKA while maintaining their quality of life. These adults need appropriate information not only about the relationship between OA suffering and quality of life, but also TKA. While these patients are deciding whether to undergo physician-recommended TKA, they also need information about preparations for surgery, postsurgical care, rehabilitation, and medicines.

• Implications for Rehabilitation

• Total knee arthroplasty (TKA) can significantly relieve pain and improve function for older adults with knee osteoarthritis (OA), but many are unwilling to receive the surgery.

• Our older adult participants with knee OA ascribed their indecision about receiving physician-recommended TKA to treatment-related, physical condition-related, surgery-related, and postsurgical care-related concerns.

• Healthcare providers need to provide appropriate information to older adults with knee OA not only about the relationship between OA suffering and quality of life, but also about TKA.

• Healthcare providers should also provide these patients information about preparing for surgery, postsurgical care, rehabilitation, and medicines while they are deciding whether to undergo TKA.

     

The influence of sex and obesity on gait biomechanics in people with severe knee osteoarthritis scheduled for arthroplasty

BackgroundSex and body mass may influence knee biomechanics associated with poor total knee arthroplasty (TKA) outcomes for knee osteoarthritis (OA). This study aimed to determine if gait differed between men and women, and overweight and class I obese patients with severe knee OA awaiting TKA.Methods34 patients with severe knee OA (average age 70.0 (SD 7.2) years, body mass index 30.3 (4.1 kg/m²)) were recruited from a TKA waiting list. Three-dimensional gait analysis was performed at self-selected walking speed. Comparisons were made between men and women, and overweight (body mass index (BMI) 25.0–29.9 kg/m²) and class I obese (BMI 30.0–34.9 kg/m²) participants. Biomechanical outcomes included absolute and body size-adjusted peak knee adduction moment (KAM), KAM impulse, peak knee flexion moment, as well as peak knee flexion and varus-valgus angles, peak varus-valgus thrust, and peak vertical ground reaction force (GRF).FindingsMen had a higher absolute peak KAM, KAM impulse and peak GRF compared to women, and this sex-difference in frontal plane moments remained after adjusting for body size. However, when additionally adjusting for static knee alignment, differences disappeared. Knee biomechanics were similar between obesity groups after adjusting for the greater body weight of those with class I obesity.InterpretationMen had greater KAM and KAM impulse even after adjustment for body size; however adjustment for their more varus knees removed this difference. Obesity group did not influence knee joint kinematics or moments. This suggests sex- and obesity-differences in these variables may not be associated with TKA outcomes.     

Knee joint angle and vasti muscle electromyograms during fatiguing contractions

We compared vasti muscle electromyograms for two knee joint angles during fatiguing tetanic contractions. Tetanic contraction of the knee extensors was evoked for 70 s by electrical stimulation of the femoral nerve at knee joint angles of 60° (extended, with 0° indicating full extension) and 110° (flexed) in eight healthy men. Surface electromyography was recorded from the vastus intermedius (VI), vastus lateralis (VL) and vastus medialis (VM) muscles. Knee extension force and M‐wave amplitudes and durations were calculated every 7 s, which were normalized by the initial value. Normalized knee extension force was decreased at the flexed knee joint angle compared with that of the extended knee joint angle (P<0·05). Decreased normalized M‐wave amplitude and increased normalized M‐wave duration of the VI were greater at the flexed knee joint angle than the extended knee joint angle (P<0·05), whereas those for the VL and VM were similar (P>0·05). These results suggest that peripheral fatigue profiles of the VI might be greater at the flexed than the extended knee joint angles, but that of VL and VM might be similar in the tested range of knee joint angles (i.e. 60°–110°) during continuous tetanic contraction induced by electrical stimulation. Therefore, greater reduction of knee extension force at the flexed knee joint angle than the extended knee joint angle may reflect fatigue development of the VI more than other quadriceps femoris components.     

全膝关节置换术后早期康复配合CPM机锻炼对膝关节功能恢复的影响

目的观察全膝关节置换术（TKA）后早期康复配合持续被动活动（CPM）机锻炼对膝关节功能恢复的疗效。方法23例TKA术后患者（28膝）随机分为治疗组（15膝）和对照组（13膝），治疗组实施早期康复功能锻炼配合CPM机锻炼，对照组仅进行CPM机锻炼。结果术前治疗组膝评分和功能评分与对照组差异无显著性意义（P〉0.05），术后两周评分与对照组差异有非常显著性意义（P〈0.01）。结论TKA术后早期康复功能锻炼配合CPM机锻炼可促进膝关节功能恢复。     

Radiofrequency treatment relieves chronic knee osteoarthritis pain: a double-blind randomized controlled trial

Chronic osteoarthritis (OA) pain of the knee is often not effectively managed with current non-pharmacological or pharmacological treatments. Radiofrequency (RF) neurotomy is a therapeutic alternative for chronic pain. We investigated whether RF neurotomy applied to articular nerve branches (genicular nerves) was effective in relieving chronic OA knee joint pain. The study involved 38 elderly patients with (a) severe knee OA pain lasting more than 3 months, (b) positive response to a diagnostic genicular nerve block and (c) no response to conservative treatments. Patients were randomly assigned to receive percutaneous RF genicular neurotomy under fluoroscopic guidance (RF group; n = 19) or the same procedure without effective neurotomy (control group; n = 19). Visual analogue scale (VAS), Oxford knee scores, and global perceived effect on a 7-point scale were measured at baseline and at 1, 4, and 12 weeks post-procedure. VAS scores showed that the RF group had less knee joint pain at 4 (p < 0.001) and 12 (p < 0.001) weeks compared with the control group. Oxford knee scores showed similar findings (p < 0.001). In the RF group, 10/17 (59%), 11/17 (65%) and 10/17 (59%) achieved at least 50% knee pain relief at 1, 4, and 12 weeks, respectively. No patient reported a post-procedure adverse event during the follow-up period. RF neurotomy of genicular nerves leads to significant pain reduction and functional improvement in a subset of elderly chronic knee OA pain, and thus may be an effective treatment in such cases. Further trials with larger sample size and longer follow-up are warranted.     

Movement pattern biofeedback training after total knee arthroplasty: Randomized clinical trial protocol

IntroductionTotal knee arthroplasty (TKA) reduces joint symptoms, but habitual movement compensations persist years after surgery. Preliminary research on movement training interventions have signaled initial efficacy for remediating movement compensations and restoring knee joint loading symmetry during dynamic functional tasks after TKA. The purpose of this clinical trial is to determine if physical rehabilitation that includes movement training restores healthy movement patterns after TKA and reduces the risk of osteoarthritis (OA) progression in the contralateral knee.Methods/design150 participants will be enrolled into this randomized controlled trial. Participants will be randomly allocated to one of two dose-equivalent treatment groups: standard rehabilitation plus movement training (MOVE) or standard rehabilitation without movement training (CONTROL). Movement training will promote between-limb symmetry and surgical knee loading during activity-based exercises. Movement training strategies will include real-time biofeedback using in-shoe pressure sensors and verbal, visual, and tactile cues from the physical therapist. The primary outcome will be change in peak knee extension moment in the surgical knee during walking, from before surgery to six months after surgery. Secondary outcomes will include lower extremity movement symmetry during functional tasks, physical function, quadriceps strength, range of motion, satisfaction, adherence, contralateral knee OA progression, and incidence of contralateral TKA.DiscussionThis study will provide insights into the efficacy of movement training after unilateral TKA, along with mechanisms for optimizing long-term physical function and minimizing negative sequelae of compensatory movement patterns.     

Contribution of components of the quadriceps femoris muscle for producing external torque in patients with patellofemoral pain syndrome

IntroductionDifferent muscular activities of the quadriceps components for producing necessary torque may change in patients with patellofemoral pain syndrome (PFPS). The aim of the current study, therefore, was to assess the contribution of each component of the quadriceps femoris muscle for producing external torque in patients with PFPS.MethodTwelve females with PFPS (24.7 ± 2.3 years) and twelve healthy matched females (25.4 ± 2.4 years) performed three consecutive knee flexion and extension movements with maximum effort at 45°/s and 300°/s using a Biodex system 3 dynamometer. Simultaneously, electromyographic (EMG) activities of the vastus medialis oblique (VMO), RF (rectus femoris) and vastus lateralis (VL) muscles were recorded using a DataLog instrument. Standard multiple regressions were used to assess the ability of EMG activities of the VMO, RF and VL muscles to predict normalized quadriceps femoris isokinetic concentric and eccentric torques at 45°/s and 300°/s in the normal and patient groups.ResultsIn the normal group, the VL and the VMO were the good predictors of quadriceps concentric torque at 45°/s and 300°/s, respectively. The VL and the RF were the good predictors of quadriceps eccentric torque at 300°/s in the patient group. No other conditions showed a considerable prediction for quadriceps torque in the normal or patient group.ConclusionFemales with PFPS differ with normal females in terms of the contribution of each component of the quadriceps femoris for producing external torque. Training the VMO for concentric contraction at both high and low velocities should be included in the management of the patients with PFPS.     

Interactive Combinations Between Gait Speed and Physical Function at Acute Phase Can Predict the Physical Activity at 2 Years After Total Knee Arthroplasty Using Classification and Regression Tree Analysis

ObjectiveTo clarify the interactive combinations of various clinical factors associated with physical activity (PA) at 2 years after total knee arthroplasty (TKA) using classification and regression tree (CART) analysis.DesignA retrospective cohort study.SettingA single university hospital.Participants286 patients who underwent TKA (N=286).Main Outcome MeasuresPA was assessed preoperatively, 3 weeks, and 2 years after TKA. Physical functions, namely, 10 m walking test (10MWT), timed Up and Go test, 1-leg standing time, isometric knee extension and flexion strength, knee joint stability, knee pain, femora-tibial angle, and the passive knee extension and flexion angle, were measured before surgery as a baseline and 3 weeks after TKA as acute phase. CART analysis was conducted to clarify the interactive combinations that accurately predict the PA at 2 years after TKA.ResultsThe results of CART analysis indicated that gait speed (≥1.05 m/s) at the acute phase after TKA was the primal predictor for the postoperative PA at 2 years. The highest postoperative PA at 2 years was determined by gait speed (≥1.05 m/s) and PA (>74.5) at the acute phase. The PA at baseline and at acute phase, as well as the body mass index were also selected as predictors of postoperative PA at 2 years.ConclusionThe present study suggested that acquiring gait speed (≥1.05 m/s) and PA (>74.5) in the postoperative acute phase is the predictive of a high PA at 2 years after TKA.     

膝骨关节炎患者股四头肌功能水平及髋关节步态运动学特征分析

目的:观察中老年膝骨关节炎(KOA)患者股四头肌功能水平及步行过程中髋关节的运动学特征。方法:选取18例KOA患者为KOA组,8例无KOA者为对照组,2组的年龄、身高、体重和身体质量指数(BMI值)相匹配。2组受试者均进行等速肌力测试、无线表面肌电测试及步态测试,测试及比较2组股四头肌峰力矩(PT值)、股内侧肌(VM)、股外侧肌(VL)和股直肌(RF)的积分肌电值(iEMG)、均方根值(RMS)、平均功率频率(MPF)及峰值髋内收、外展角度等和步行中髋关节的运动学特征,将股四头肌肌力与髋关节运动学特征进行相关性分析。结果:KOA组股四头肌等长和等速运动时PT值较对照组显著下降(P<0.01),VL在60°/s等速收缩时表面肌电信号RMS值显著高于对照组(P<0.05),RF在180°/s等速收缩时表面肌电信号RMS值显著高于对照组(P<0.01),步行时峰值髋关节内收及外展角度显著低于对照组(P<0.05),股四头肌肌力与髋关节运动学特征无相关。结论:KOA组较对照组股四头肌肌力显著降低,活动时神经支配效率显著下降,且步行过程中峰值髋内收、外展角度显著减少,股四...