The flexion relaxation phenomenon in nonspecific chronic low back pain: prevalence, reproducibility and flexion-extension ratios. A systematic review and meta-analysis.

PURPOSE: The flexion relaxation phenomenon (FRP) is characterized by the reduction of paraspinal muscle activity at maximum trunk flexion. The FRP is reported to be altered (persistence of spinal muscle activity) in nonspecific chronic low back pain (NSCLBP) and is considered a promising biomarker. The aim of this systematic review was to synthetize current knowledge on FRP in the NSCLBP population regarding prevalence, the reliability of FRP measurement using surface electromyography (sEMG), the average value, and variation of the relaxation ratios (RR). METHODS: Five databases were searched (PubMed, EMBASE, Web of Sciences, Cochrane Library, Pedro). A qualitative analysis was done for all included studies and meta-analysis studying prevalence, mean value of flexion relaxation ratio (FRR) and extension relaxation ratio (ERR), and difference between asymptomatic and NSCLBP FRR. RESULTS: Twenty-seven studies were included for qualitative analysis and 21 studies for meta-analysis. The prevalence of the altered FRP was 55% (95%CI [32-79%]) in the NSCLBP population. The studies on reliability reported good within-session and between-session reproducibility. In the NSLBP population, the mean FRR was 2.96 (95%CI [2.02; 3.90]) and the mean ERR was 4.07 (95%CI [2.08; 6.07]). The difference between asymptomatic and NSCLBP FRR was - 1.19 (95%CI [- 1.92, - 0.45]). In all meta-analysis, the I2 index was > 80%. CONCLUSION: An altered FRP is frequently found in NSCLBP population using sEMG and the test has a good reproducibility. The difference between asymptomatic and NSCLBP FRR was significant. Nevertheless, considering the high heterogeneity observed, additional research is required to confirm the value of RR.

Botulinum Toxin A for Chronic Exertional Compartment Syndrome: A Retrospective Study of 16 Upper- and Lower-Limb Cases.

OBJECTIVE: To assess initial and mid-term efficacy of botulinum toxin A (BoNT-A) injections in patients with chronic exertional compartment syndrome (CECS) in the lower and upper limbs. DESIGN: Retrospective monocentric study. SETTING: A University Hospital Department of Physical Medicine and Rehabilitation. PATIENTS: Sixteen patients with CECS of the lower and upper limbs treated with BoNT-A injections (first-line treatment) were included. INTERVENTIONS, MAIN OUTCOME MEASURES: We collected data from a follow-up consultation (initial pain reduction [complete, partial, or ineffective] and specific activities triggering CECS) and a subsequent phone questionnaire (mid-term efficacy, pain recurrence, and adverse effects). RESULTS: Sixteen patients were included (median age: 25.5 years), and 68.75% reported initial efficacy (4 partial and 7 complete); 8/16 patients were able to resume the activity that triggered CECS. All the patients with initial partial efficacy had pain recurrence (median time of 2.25 months). Among patients with initial complete efficacy, 57.14% had recurrence (median time of 5 months). Minor adverse effects were observed, but with no functional impact. CONCLUSION: In 16 individuals with CECS treated with BoNT-A injections, we observed moderate efficacy without major adverse effects, but an initial improvement was often followed by recurrence, especially among those with partial initial efficacy.

Is the Short and Fast Step Test a safe and feasible tool for exploring anaerobic capacities of individuals with coronary heart disease in clinical practice?

BACKGROUND: While its importance in daily living, the anaerobic metabolism is not taken into account in clinical practice. The lack of validated functional performance tests for patients with chronic disabilities may explain this defect. In this context, the Short and Fast Step Test (SFST) was recently developed and validated in healthy volunteers. AIM: The purpose of this study was to investigate the safety, feasibility and reliability of the SFST, a functional test exploring anaerobic metabolism in coronary patients during cardiac rehabilitation. DESIGN: This study was a monocentric prospective study. SETTING: This study took place in the rehabilitation center of the University Hospital Center of Dijon, France. POPULATION: Forty-four coronary patients addressed for a first cardiac rehabilitation were included in this protocol. METHODS: All participants performed three SFST: T1 and T2 (including respiratory gas exchange) the first day of the program and T3 after 3 to 7 days. SFST consists of walking up and down a 17.5 cm-high step as many times as possible in 1 minute. Safety was assessed by the percentage of patients who performed the SFST without reporting a fall, or muscular or cardiovascular events. Feasibility was evaluated by the percentage of patients who succeeded in doing the SFST. Reliability was assessed with the number of raised steps in same condition (T1-T3) and different conditions (T1-T2) using a 2-way intraclass correlation coefficient (ICC). Values were given with their 90% confidence interval [90% CI]. RESULTS: The safety was 95.2% [85.8-99.2] for T1, 88.1% [76.6-95.2] for T2 and 90.4% [79.5-96.7] for T3. 100% [93.1-100] of participants completed T1 and T2, 92.9% [82.6-98] T3. An ICC of 0.74 [0.60-0.84] was observed between T1 and T3 and of 0.87 [0.79-0.92] between T1 and T2. CONCLUSIONS: This study demonstrates the good safety, feasibility and reliability of the SFST to assess anaerobic metabolism in coronary patients in a rehabilitation program. CLINICAL REHABILITATION IMPACT: These results show that the SFST seems suitable for the evaluation of brief submaximal functional capacity in daily activities. It offers a real possibility to assess such capacity during the cardiac rehabilitation routine.

A tool to improve functional outcome assessment of a multimodal program for patients with chronic low back pain: A study on walk tests (at comfortable and fast speed).

BACKGROUND: Tools for functional assessment of chronic low back pain (LBP) are lacking. OBJECTIVE: To determine the correlations and the responsiveness of the 400 m comfortable walk test (400 mCWT) and the 200 m fast-walk test (200 mFWT) in the functional assessment of a multimodal program. METHODS: One hundred and twenty-seven participants (68 females) with LBP and with or without radicular pain completed a Quebec Back Pain Disability Scale, a Sorensen test, a Shirado test, a 400 mCWT and a 200 mFWT, at baseline and at the end of the program. RESULTS: No significant side effect was reported during walk tests. Walking speed was significantly increased after the program (0.18 ± 0.15 m.s-1 for the 400 mCWT and 0.17 ± 0.17 m.s-1 for the 200 mFWT). Clinical parameters were also significantly improved (82.02 ± 83.1 seconds for the Shirado, 92.1 ± 100.1 seconds for the Sorensen, -14.0 ± 12.9 for the Quebec scale). A significant relationship was found between the increase in walking speed for the two walk tests and the improvement of the Quebec scale. The gait speed improvement was close to the minimal clinically important change (95% confidence interval: 0.14-0.22) determined from the Quebec scale threshold (minimum detectable change). CONCLUSIONS: Both 400 mCWT and 200 mFWT are correlated with functional parameters and are responsive for the functional assessment of LBP.

Training with FES-assisted cycling in a subject with spinal cord injury: Psychological, physical and physiological considerations.

CONTEXT: People with spinal cord injury (SCI) experience the effects of a sedentary lifestyle very early on. Literature data suggest that programs using FES-assisted cycling would contribute to reduce the consequences of physical inactivity. The objective was to assess the feasibility of 12-month training on a FES-assisted bike of a subject with paraplegia for 21 years, T3, Asia Impairment Scale (AIS) A. An evaluation of morbidity, self-esteem, satisfaction, quality of life and duration of pedaling was performed. The impact on pain, cardiorespiratory function, body composition and bone metabolism were also assessed. FINDINGS: The acceptability score of the training constraints increased from 51 to 59/65 and satisfaction was high around 8/10. The pedaling duration increased from 1' to 26' on the recumbent bike and from 1' to 15' on open terrain. No significant changes were found with BMD and cardiorespiratory measures during exercise tests. SF 36 showed significant improvement of more than 10% and the Rosenberg Self Esteem score rapidly improved from 36 to 39/40. At the end of the training, the patient reached the objective of the Cybathlon 2016 by covering 750 m in less than 8 minutes, at an average speed of 5.80 km/hr. CONCLUSION/CLINICAL RELEVANCE: A person with high and complete level of SCI for more than 20 years can undertake this type of challenge if the prerequisites are met; this training is without danger if the safety precautions are respected; the challenge of participating in a competition had a powerful impact on JP's self-esteem and perceived quality of life.

Age-Related Adaptations of Lower Limb Intersegmental Coordination During Walking.

Lower-limb intersegmental coordination is a complex component of human walking. Aging may result in impairments of motor control and coordination contributing to the decline in mobility inducing loss of autonomy. Investigating intersegmental coordination could therefore provide insights into age-related changes in neuromuscular control of gait. However, it is unknown whether the age-related declines in gait performance relates to intersegmental coordination. The aim of this study was to evaluate the impact of aging on the coordination of lower limb kinematics and kinetics during walking at a conformable speed. We then assessed the body kinematics and kinetics from gait analyses of 84 volunteers from 25 to 85 years old when walking was performed at their self-selected speeds. Principal Component Analysis (PCA) was used to assess lower-limb intersegmental coordination and to evaluate the planar covariation of the Shank-Thigh and Foot-Shank segments. Ankle and knee stiffness were also estimated. Age-related effects on planar covariation parameters was evaluated using multiple linear regressions (i.e., without a priori age group determination) adjusted to normalized self-selected gait velocity. Colinearity between parameters was assessed using a variation inflation factor (VIF) and those with a VIF < 5 were entered in the analysis. Normalized gait velocity significantly decreased with aging (r = -0.24; P = 0.028). Planar covariation of inter-segmental coordination was consistent across age (99.3 ± 0.24% of explained variance of PCA). Significant relationships were found between age and intersegmental foot-shank coordination, range of motion of the ankle, maximal power of the knee, and the ankle. Lower-limb coordination was modified with age, particularly the coordination between foot, and shank. Such modifications may influence the ankle motion and thus, ankle power. This observation may explain the decrease in the ankle plantar flexor strength mainly reported in the literature. We therefore hypothesize that this modification of coordination constitutes a neuromuscular adaptation of gait control accompanying a loss of ankle strength and amplitude by increasing the knee power in order to maintain gait efficiency. We propose that foot-shank coordination might represent a valid outcome measure to estimate the efficacy of rehabilitative strategies and to evaluate their efficiency in restoring lower-limb synergies during walking.

Walking Speed as an Alternative Measure of Functional Status in Patients with Lumbar Spinal Stenosis.

OBJECTIVE: The main objective was to compare estimated walking perimeter (WP) and actual WP during a free walking test (6-minute walk test [6MWT]) in patients with lumbar spinal stenosis (LSS). The second objective was to describe the correlation between measured gait parameters and functional parameters. METHODS: This was a single-center prospective study including 38 patients with symptomatic LSS (23 men, 15 women; mean age, 69.3 ± 7.9 years). The intervention was the 6MWT. For the main outcome measure, patients were first asked to verbally estimate their WP. Then, WP was evaluated using a 6MWT at a self-selected speed. In the absence of need to stop, and if a distance of 500 m was not reached, the test was extended to this distance. Specific functional scores (Oswestry Disability Index and Quebec Back Pain Disability Scale) were recorded, and a quality of life questionnaire was completed. RESULTS: WP was estimated to be less than 500 m in 21 of 38 patients, but only 7 patients actually stopped walking before reaching 500 m. The median estimate error in these patients was 200 m (interquartile range, 65-250). The shorter the estimated distance was, the greater the estimation error (r = -0.63, P=0.002). The average walking speed was slow. Functional parameters (Oswestry Disability Index and Quebec Back Pain Disability Scale) were weakly and inversely correlated with real WP (r = -0.44 and r = -0.31, respectively) and moderately inversely correlated with measured walking speed (r = -0.51, P = 0.001 for both). CONCLUSIONS: Direct measurement of free walking speed should be considered as a valid functional assessment in current practice for patients with LSS instead of estimated WP. To assist therapeutic decision-making, the most relevant type of walking test (duration, distance, velocity) needs to be determined.

Number of raised steps: A tool to assess brief and intense effort involving anaerobic metabolism.

BACKGROUND: Although the initial anaerobic component of exercise adaptation is unavoidable, no specific functional test is available for use in routine non-sporting practice to evaluate it. OBJECTIVE: To assess the bioenergetic and biomechanical properties of the Short and Fast Step Test (SFST), which consists of walking up and down a step as many times as possible in 1minute and to analyse its ability to explore the initial anaerobic component of effort in comparison to a reference self-paced step test. METHODS: Overall, 31 healthy subjects (19 women; mean [SD] age, 32.4 [10.2] years) completed a test-retest of a self-paced step test and the SFST, with pre- and post-test measurement of blood lactate concentration and continuous recording of VO2 and modelling of excess post-exercise oxygen consumption (EPOC), near-infrared spectroscopy (NIRS) of the quadriceps and mechanical power (estimated by the number of steps climbed and 3-D motion analysis). RESULTS: Both step tests were well tolerated. The reliability of the bioenergetics parameters, number of raised steps, mechanical power and NIRS tissue saturation index was good. Indirect mechanical power (estimated from number of steps) was correlated with direct power (computed from the centre of mass). Lactate accumulation was significantly increased during exercise with only the SFST (mean [SD] increase, 3.86 [3.26]mmolL-1 from resting values, P<0.05). EPOC was higher with the SFST than the self-paced step test (P<0.05). Only the SFST showed significant correlations between number of steps climbed and EPOC (r=0.84; P<0.001) and decreased tissue saturation index (NIRS) and EPOC area (r=-0.39; P<0.05). CONCLUSIONS: SFST is feasible, well tolerated, reliable and responsive to explore a brief exercise involving anaerobic metabolism at submaximal intensity. The number of steps taken in 1minute seems a suitable parameter for practical application.

Microcirculatory Assessment of Arterial Below-Knee Stumps: Near-Infrared Spectroscopy Versus Transcutaneous Oxygen Tension-A Preliminary Study in Prosthesis Users.

OBJECTIVE: To examine metrologic properties of near-infrared spectroscopy (NIRS) versus transcutaneous oxygen tension (TcPO2) for microcirculatory assessment of vascular transtibial stumps at the stabilized period of prosthesis fitting, as a preliminary step before exploring its ability to predict stump healing, considering the previously identified limits of TcPO2 (borderline area between 15 and 35mmHg). DESIGN: Prospective single-center observational study. SETTING: University-based rehabilitation center. PARTICIPANTS: Individuals with unilateral transtibial amputation for peripheral artery disease, at the definitive stage of prosthesis fitting, able to perform a 2-minute walk test (N=30). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Test-retest, with the stump being evaluated in supine and inclined positions, first by NIRS (tissue saturation index [TSI], oxyhemoglobin, deoxyhemoglobin, and total hemoglobin) and second by TcPO2. Subjects carried out a 2-minute walk test and visual analog scales (wound healing and pain). RESULTS: Feasibility and tolerance of NIRS were satisfactory. The reliability of NIRS and TcPO2 values was good (intraclass correlation coefficient >0.7; P<.05). No significant relation was found between NIRS and TcPO2. No responsiveness (inclined vs supine) was reported (P>.05). A significant relation between TSI and the 2-minute walk test (r>.49, P<.05) was found. CONCLUSIONS: NIRS is painless, complication-free, and feasible, with good reliability. NIRS evaluates others domain than TcPO2 that are more linked to metabolic adaptation. Its capacity to predict stump healing and tolerance to early prosthesis fitting is therefore interesting to estimate in future studies.

Assessment tools for personalizing training intensity during cardiac rehabilitation: Literature review and practical proposals.

Exercise training, associated with therapeutic education, is the main axis of cardiac rehabilitation (CR) programs. The aim of this study was to review the literature for descriptions of the various assessments of exercise tolerance used to prescribe exercise intensity during CR. A secondary objective was to attempt to formulate a rational practice with these assessments in CR programs.

One year of training with FES has impressive beneficial effects in a 36-year-old woman with spinal cord injury.

CONTEXT: Reductions of muscular and cardiorespiratory functions are often observed in people with spinal cord injury (SCI) and several studies demonstrated the benefits of aerobic and strengthening exercise training for this population. Functional Electrical Stimulation (FES) of paralyzed muscles has been proposed as a strategy to assist patients in executing functional movement but its utilization during long durations has never been investigated. The purpose of the present study was to assess the effects of a one-year training program with FES (strengthening and rowing) in one subject with SCI. Evoked torque, quadriceps muscle thickness, aerobic exercise capacity and bone mineral density were tested. FINDINGS: All parameters increased after training: average evoked torque +151%, quadriceps muscle thickness +136%, thigh circumference +14%, bone density +19%, maximal oxygen uptake +76% and oxygen uptake at ventilatory threshold +111%. CONCLUSION: These impressive improvements demonstrate that FES training offers several interesting clinical benefits in a patient with SCI.

Fixed-distance walk tests at comfortable and fast speed: Potential tools for the functional assessment of coronary patients?

OBJECTIVES: There is ambiguity concerning the walk tests available for functional assessment of coronary patients, particularly for the walking speed. This study explores the psychometric properties of two walking tests, based on fixed-distance tests, at comfortable and fast velocity, in stabilized patients at the end of a cardiac rehabilitation program. METHODS: At a three-day interval 58 coronary patients (mean age of 64.85±6.03 years, 50 men) performed three walk tests, the first two at a comfortable speed in a random order (6-minute walk test - 6MWT - and 400-metre comfortable walk test - 400mCWT) and the third at a brisk speed (200-metre fast walk test - 200mFWT). A modified Bruce treadmill test was associated at the end of the second phase. Monitored main parameters were: heart rate, walking velocity, VO2. RESULTS: Tolerance to the 3 tests was satisfactory. The reliability of the main parameters was good (intraclass correlation coefficient>0.8). The VO2 concerning 6MWT and 400mCWT were not significantly different (P=0.33) and were lower to the first ventilatory threshold determined by the stress test (P<0.001): 16.2±3.0 vs. 16.5±2.6 vs. 20.7±5.1mL·min-1·kg-1 respectively. The VO2 of the 200mFWT (20.2±3.7) was not different from the first ventilatory threshold. CONCLUSIONS: 400mCWT and 200mFWT are feasible, well-tolerated and reliable. They explore two levels of effort intensity (lower and not different to the first ventilatory threshold respectively). 400mCWT is a possible alternative to 6MWT. Associated with 200mFWT it should allow a better measurement of physical capacities and better customization of exercise training.

The Log book for the secondary prevention of coronary artery disease: A pilot study.

INTRODUCTION: In secondary prevention (SP) of coronary artery disease (CAD), in particular after an acute myocardial infarction (MI), a better knowledge and self-management by the patient may have various supports. The Log book (LB) for CAD patients in Côte d'Or, was created in 2010 by a multidisciplinary team of healthcare professionals of Côte d'Or, from a regional care network. This pilot study evaluated LB as novel support for SP after acute MI. METHODS: A prospective study on 183 patients hospitalised for an acute MI in the region of Côte d'Or from 1st May to 30th October 2010. Patients were randomized in 91 patients who received an LB at the time of their hospitalisation (LB+ group), and 92 patients who were not given an LB (LB- group). The follow up (FU) was performed at 4 months and 1 year. RESULTS: Baseline characteristics were similar in the 2 groups, except for smoking, which was more frequent in the LB-group than in the LB+ group. At FU, LB was usually well accepted by both patients and their general practitioners (GP). At 4 months FU, the patients LB+ were more prone to see their general practitioners than patients LB- (100% vs 85% in the LB- group, P=0.007). Moreover, in LB+ group, there was a trend towards a more frequent physical activity, including exercise bike (P=0.009) and an increase in HDL-cholesterol (HDL-c) (P=0.165). At 1 year FU, body mass index from LB+ was more reduced than in patients LB- (P=0.029). Finally, there was a trend towards lower morbi-mortality (hospitalisation for cardiovascular cause or death) in the LB+ group than in the LB- group (11 vs 22%, P=0.083). CONCLUSION: This pilot study showed the feasibility of LB as a support for SP and its interest in post MI management in a local care network setting. In addition, our study provides encouraging data on the potential benefits of this pioneer tool for SP.