Vivienne Chuter

Exercise interventions for the treatment of chronic low back pain: a systematic review and meta-analysis of randomised controlled trials

Objective: To determine, for adults with chronic low back pain, which exercise interventions are the most effective at reducing pain compared to other treatments. Data sources: A search of MEDLINE, CINAHL, EMBASE, SPORTDiscus, PsycINFO and The Cochrane Library was conducted up to October 2014. Review methods: Databases were searched for published reports of randomised trials that investigated the treatment of chronic low back pain of non-specific origin with an exercise intervention. Two authors independently reviewed and selected relevant trials. Methodological quality was evaluated using the Downs and Black tool. Results: Forty-five trials met the inclusion criteria and thirty-nine were included in the meta-analysis. Combined meta-analysis revealed significantly lower chronic low back pain with intervention groups using exercise compared to a control group or other treatment group (Standard Mean Deviation (SMD) =-0.32, CI 95% -0.44 to -0.19, P<0.01). Separate exploratory subgroup analysis showed a significant effect for strength/resistance and coordination/stabilisation programs. Conclusions: Our results found a beneficial effect for strength/resistance and coordination/stabilisation exercise programs over other interventions in the treatment of chronic low back pain and that cardiorespiratory and combined exercise programs are ineffective.

Effect of aerobic exercise training dose on liver fat and visceral adiposity

BACKGROUND & AIMS Aerobic exercise reduces liver fat and visceral adipose tissue (VAT). However, there is limited data from randomized trials to inform exercise programming recommendations. This study examined the efficacy of commonly prescribed exercise doses for reducing liver fat and VAT using a randomized placebo-controlled design. METHODS Inactive and overweight/obese adults received 8 weeks of either; i) low to moderate intensity, high volume aerobic exercise (LO:HI, 50% VO 2peak, 60 min, 4d/week); ii) high intensity, low volume aerobic exercise (HI:LO, 70% VO 2peak, 45 min, 3d/week); iii) low to moderate intensity, low volume aerobic exercise (LO:LO, 50% VO 2peak, 45 min, 3d/week); or iv) placebo (PLA). Liver fat (spectroscopy) and VAT (magnetic resonance imaging) were measured before and after intervention. RESULTS Forty-seven of the 48 (n = 12 in each group) participants completed the trial. There were no serious adverse events. There was a significant change in group × time interaction in liver fat, which reduced in HI:LO by 2.38 ± 0.73%, in LO:HI by 2.62 ± 1.00%, and in LO:LO by 0.84 ± 0.47% but not in PLA (increase of 1.10 ± 0.62%) (p = 0.04). There was a significant reduction in VAT in HI:LO (-258.38 ± 87.78 cm(3)), in LO:HI (-386.80 ± 119.5 cm(3)), and in LO:LO (-212.96 ± 105.54 cm(3)), but not in PLA (92.64 ± 83.46 cm(3)) (p = 0.03). There were no significant differences between the dose or intensity of the exercise regimen and reductions in liver fat or VAT (p > 0.05). CONCLUSION The study found no difference in efficacy of liver fat reduction by either aerobic exercise dose or intensity. All of the aerobic exercise regimens employed reduced liver fat and VAT by a small amount without clinically significant weight loss.

Proximal and distal contributions to lower extremity injury: A review of the literature

Excessive or prolonged foot pronation has been linked to the development of numerous overuse injuries affecting the lower limb. The originally proposed pathomechanical model suggests foot motion affects more proximal structures through disruption of distal to proximal coupling between the foot, tibia, femur, and hip. Research evidence supports the presence of a dynamic coupling mechanism between lower limb segments, however, the direction of the coupling is inconclusive. Recent prospective investigations of the role of the lumbo-pelvic hip complex have identified a strong association between proximal dysfunction and increased risk of lower limb injuries. Strength of muscles of the lumbo-pelvic hip complex (core muscles) is suggested to be essential to controlling hip abduction, subsequent internal rotation of the femur and potentially more distal movement. Proximal muscle weakness and altered motor control have also been implicated in the development of numerous lower limb injuries, many of which have previously been attributed to excessive foot pronation. This review discusses the theoretical basis for the role of proximal and distal structures in biomechanical dysfunction of the lower limb and the development of lower limb overuse injury. Current prospective evidence relating to the contributions of excessive foot pronation and core muscle function to the development of lower extremity injury is evaluated.

The relationship between foot motion and lumbopelvic–hip function: A review of the literature

Excessive pronation has been implicated in the development of numerous overuse injuries of the lower limb and is suggested to cause more proximal biomechanical dysfunction. Functional foot orthoses (FFO) are frequently prescribed for lower limb injury associated with excessive foot pronation and have been demonstrated to have efficacy with specific conditions. However, the mechanism of action of FFO is largely unknown. Research investigating the kinematic and kinetic changes associated with FFO use is inconclusive. Furthermore there is a growing body of evidence suggesting that changes to muscle activity patterns in response to FFO may be responsible for their therapeutic effect. Additionally, current research suggests dysfunction of musculature of the lumbopelvic-hip complex is involved in lower extremity functional changes and is related to the development some pathologies traditionally attributed to excessive foot pronation. Evidence of temporal coupling between the hip and the foot and changes in hip muscle activity associated with FFO use further suggest a relationship between proximal and distal lower limb function. The aim of this review is to discuss the association between foot and lumbopelvic-hip complex dysfunction and injury, assess the evidence for functional changes to lower limb and lumbopelvic-hip function with FFO use and finally to discuss the potential for changes to hip musculature activation with FFO use to influence distal mechanics and produce a therapeutic benefit.

Relationships between foot type and dynamic rearfoot frontal plane motion

BackgroundThe Foot Posture Index (FPI) provides an easily applicable, validated method for quantifying static foot posture. However there is limited evidence relating to the ability of the FPI to predict dynamic foot function. This study aimed to assess the relationship between dynamic rearfoot motion and FPI scores in pronated and normal foot types.Methods40 participants were recruited with equal numbers of pronated and normal foot types as classified by their FPI score. Three dimensional rearfoot motion was collected for each of the participants. Dynamic maximum rearfoot eversion was correlated with the total FPI score across all participants and within the normal and pronated foot types. Linear correlations were performed between components of the total FPI scores measuring frontal plane rearfoot position and maximum rearfoot eversion. The capacity of the total FPI score to predict maximum frontal plane motion of the rearfoot was investigated using linear regression analysis.ResultsThe correlation between the total FPI score and maximum rearfoot eversion was strongly positive (r = 0.92, p < 0.05). Correlation performed on data subsets demonstrated the pronated foot type (FPI = +6 to +9) and maximum rearfoot eversion angle were more strongly positively correlated (r = 0.81, p < 0.05) than the normal foot type (FPI = 0 to +5) and maximum rearfoot eversion (r = 0.76, p < 0.05). Correlations between frontal plane rearfoot FPI score and frontal plane motion during gait were strongly positive, (r = 0.79 p < 0.05 pronated group, r = 0.71 p < 0.05 normal group), however were less strong than the total FPI score and rearfoot motion. Linear regression analysis demonstrated a significant and strong relationship between the total FPI score and maximum rearfoot eversion (r2 = 0.85, p < 0.001).ConclusionsThe results of this study suggest the FPI has strong predictive ability for dynamic rearfoot function. This will assist in clinical screening and research by allowing easy classification by functional foot type. Positive correlations between frontal plane rearfoot measurements and maximum rearfoot eversion suggest the FPI may identify dominant planar components of dynamic rearfoot motion and warrants further investigation.

Non-invasive vascular assessment in the foot with diabetes: sensitivity and specificity of the ankle brachial index, toe brachial index and continuous wave Doppler for detecting peripheral arterial disease

BACKGROUND & AIMS Non-invasive lower limb vascular assessment in people at risk of peripheral arterial disease (PAD) including those with diabetes is crucial. There is evidence that standard assessment techniques such as the ankle-brachial index (ABI) may be less effective in people with diabetes. However there is limited evidence for other frequently used tests including continuous wave Doppler (CWD), and the toe-brachial index (TBI). The aim of this study was to determine the sensitivity and specificity of, ABI, CWD and TBI in a population with, and without diabetes. METHODS Participants with and without diabetes who met current guidelines for vascular screening were recruited, and CWD waveforms, an ABI and a TBI were obtained from the right lower limb. Diagnostic accuracy was determined using colour duplex ultrasound (CFDU). Receiver operating characteristic curves were calculated. RESULTS 117 participants were recruited, seventy-two with diabetes and forty-five without diabetes. CWD had the highest sensitivity in people with diabetes (74%) and without (84%). CWD also had the highest specificity in people with diabetes (74%) and without (84%) compared to both TBI and ABI. In participants with diabetes, the ABI was a poor test, area under the curve: 0.58 (p=0.27). CONCLUSIONS CWD waveform is more likely to detect significant PAD compared to ABI and TBI in people with and without diabetes.

Exercise Performance over the Menstrual Cycle in Temperate and Hot, Humid Conditions.

PURPOSE This study investigated the effects of the menstrual cycle on prolonged exercise performance both in temperate (20°C, 45% relative humidity) and hot, humid (32°C, 60% relative humidity) conditions. METHODS For each environmental condition, 12 recreationally active females were tested during the early follicular (day 3-6) and midluteal (day 19-25) phases, verified by measurement of estradiol and progesterone. For all four tests, thermoregulatory, cardiorespiratory, and perceptual responses were measured during 60 min of exercise at 60% of maximal oxygen consumption followed by an incremental test to exhaustion. RESULTS No differences in exercise performance between menstrual cycle phases were found during temperate conditions (n = 8) despite a higher resting and submaximal exercise core temperature (Tc) in the luteal phase. In hot, humid conditions (n = 8), however, prolonged exercise performance, as exercise time to fatigue, was significantly reduced during the luteal phase. This finding was not only accompanied by higher resting and submaximal exercise Tc but also a higher rate of increase in Tc during the luteal phase. Furthermore, submaximal exercise HR, minute ventilation, and RPE measures were higher during the luteal phase in hot, humid conditions. No significant differences were found over the menstrual cycle in heat loss responses (partitional calorimetry, sweat rate, upper arm sweat composition) and Tc at exhaustion. CONCLUSION In temperate conditions, no changes in prolonged exercise performance were found over the menstrual cycle, whereas in hot, humid conditions, performance was decreased during the luteal phase. The combination of both exercise and heat stress with the elevated luteal phase Tc at the onset of exercise resulted in physiological and perceptual changes and a greater thermosensitivity, which may explain the decrease in performance.

Variability of neutral-position casting of the foot.

Neutral-position casting of the foot is used for the manufacture of functional foot orthoses, and an accurate cast is widely assumed to be a prerequisite for a good orthotic device. The primary aim of this study was to determine the variability of casting between inexperienced and experienced clinicians and the variability of one experienced clinician taking multiple casts. Ten inexperienced and ten experienced clinicians took a cast of the right foot of a single subject, and a single experienced clinician took ten casts of the same foot. The frontal plane forefoot-to-rearfoot relationship of each cast was determined, and no difference was found in the mean and variances among the three groups. The range of the forefoot-to-rearfoot relationship across all groups was from 10.0 degrees everted to 6.5 degrees inverted, indicating that there is a wide range in neutral-position casting of the foot. As outcome studies have reported the successful outcomes of functional foot orthoses, this wide variability may not necessarily be a problem.

Sensitivity and specificity of the functional hallux limitus test to predict foot function

Functional hallux limitus is an underrecognized entity that generally does not produce symptoms but can result in a variety of compensatory mechanisms that can produce symptoms. Clinically, hallux limitus can be determined by assessing the range of motion available at the first metatarsophalangeal joint while the first ray is prevented from plantarflexing. The aim of this study was to determine the sensitivity and specificity of this clinical test to predict abnormal excessive midtarsal joint function during gait. A total of 86 feet were examined for functional hallux limitus and abnormal pronation of the midtarsal joint during late midstance. The test had a sensitivity of 0.72 and a specificity of 0.66, suggesting that clinicians should consider functional hallux limitus when there is late midstance pronation of the midtarsal joint during gait.

The effectiveness of shoe insoles for the prevention and treatment of low back pain: a systematic review and meta-analysis of randomised controlled trials

BackgroundLow back pain (LBP) is a significant public health problem in Western industrialised countries and has been reported to affect up to 80% of adults at some stage in their lives. It is associated with high health care utilisation costs, disability, work loss and restriction of social activities. An intervention of foot orthoses or insoles has been suggested to reduce the risk of developing LBP and be an effective treatment strategy for people suffering from LBP. However, despite the common usage of orthoses and insoles, there is a lack of clear guidelines for their use in relation to LBP. The aim of this review is to investigate the effectiveness of foot orthoses and insoles in the prevention and treatment of non specific LBP.MethodsA systematic search of MEDLINE, CINAHL, EMBASE and The Cochrane Library was conducted in May 2013. Two authors independently reviewed and selected relevant randomised controlled trials. Quality was evaluated using the Cochrane Collaboration Risk of Bias Tool and the Downs and Black Checklist. Meta-analysis of study data were conducted where possible.ResultsEleven trials were included: five trials investigated the treatment of LBP (n = 293) and six trials examined the prevention of LBP (n = 2379) through the use of foot orthoses or insoles. Meta-analysis showed no significant effect in favour of the foot orthoses or insoles for either the treatment trials (standardised mean difference (SMD) -0.74, CI 95%: -1.5 to 0.03) or the prevention trials (relative risk (RR) 0.78, CI 95%: 0.50 to 1.23).ConclusionsThere is insufficient evidence to support the use of insoles or foot orthoses as either a treatment for LBP or in the prevention of LBP. The small number, moderate methodological quality and the high heterogeneity of the available trials reduce the strength of current findings. Future research should concentrate on identification of LBP patients most suited to foot orthoses or insole treatment, as there is some evidence that trials structured along these lines have a greater effect on reducing LBP.