Non-drug therapies for lower limb muscle cramps

Comparative evaluation of the potential anti-spasmodic activity of Piper longum, Piper nigrum, Terminalia bellerica, Terminalia chebula, and Zingiber officinale in experimental animals

Background

Spasm of muscle is one of the frequent complaints seen by most of the population worldwide. The present study evaluated the efficacy of some of the commonly used herbal extracts against known spasmogens, such as histamine and 5-hydroxytryptamine (5-HT).

Material and methods

The study was conducted on isolated guinea pig ileum and rat uterus preparations using histamine and 5-HT, respectively. Five herbal extracts such as Piper longum (P.L), Piper nigrum (P.N), Terminalia bellerica (T.B), Terminalia chebula (T.C), and Zingiber officinale (Z.O) were tested. Herbal extracts at doses 50, 150, 500, 1500, and 5000 mcg/ml were pretreated to the isolated tissue preparation, and the contractile response of histamine and 5-HT was recorded. The efficacy and the inhibitory concentration (IC50) were calculated and statistically analyzed by one-way ANOVA.

Results

The study indicated that all five herbal extracts produced a concentration-dependent suppression of histamine and 5-HT-induced responses. A significant (p < 0.05) non-competitive antagonism was observed against the known spasmogen induced smooth muscle contraction for P.L, P.N, T.B, and Z.O in both guinea pigs and rat uterus preparation. Moreover, P.L and P.N completely abolished (100%) the contractile response induced by histamine and 5-HT. Although, T.C produced a concentration-dependent reduction in known spasmogen-induced contraction but the response was found to be statistically non-significant (p greater than 0.05).

Conclusion

The finding suggested that P.L. and P.N. have better activity in terms of reducing the spasmogenic contractions compared to other extracts. Additionally, T.B. and Z.O. can lessen the uterine and intestinal contractions brought on by spasmogens. Although P.L and P.N demonstrated better efficacy against the spasmogenic activity of histamine and 5-HT, more research, particularly on isolated phytochemicals of the extracts and involving different experimental models, is required before establishing the precise safety and efficacy against spasmogenic-induced disorders.

Patient-Reported Prevalence, Characteristics, and Impact of Leg Cramps in an Urban Primary Care Clinic

This study addresses the prevalence and characteristics of leg cramps in 294 primary care patients (mean age = 46.5 years), with 51.7% reporting leg cramps. Patients who experience resting or exercise-induced leg cramps were more likely to be older and female. Cramp severity averaged 5.6 on a scale of 1-10 and disturbed sleep "sometimes" or "often" in 55% of patients. Most patients did not discuss cramps with their clinician. Our study reveals a possible shift in patients who experience leg cramps to younger age and chronicity. Resting leg cramps should be reviewed by clinicians as a symptom of declining health and advancing aging.

[Sleep disorders in patients with neuromuscular diseases]

Neuromuscular diseases (NMD) may affect skeletal muscles, peripheral nerves, or motor endplates. Clinical symptoms comprise muscle weakness, which is often progressive, but also sensory disturbances, and primary or secondary pain. Sleep disturbances in NMD may result from insomnia due to immobility, pain, or sleep-related leg muscle cramps, but also restless legs syndrome and sleep-disordered breathing. Many NMD predispose to obstructive sleep apnea or progressive respiratory muscle weakness, which first manifests as sleep-related hypoventilation and eventually leads to chronic hypercapnic respiratory failure. The latter is crucial for overall prognosis in muscular dystrophies and myopathies, but even more so in motor neuron diseases such as amyotrophic lateral sclerosis and spinal muscular atrophy.

Non-drug therapies for the secondary prevention of lower limb muscle cramps

BACKGROUND

Lower limb muscle cramps are common and painful. They can limit exercise participation, and reduce quality of sleep, and quality of life. Many interventions are available for lower limb cramps; some are controversial or could cause harm, and often, people experience no benefit from the interventions used. This is an update of a Cochrane Review first published in 2012. We updated the review to incorporate new evidence.

OBJECTIVES

To assess the effects of non-drug, non-invasive therapies for lower limb muscle cramps.

SEARCH METHODS

In August 2018 and May 2020, we searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, the World Health Organization International Clinical Trials Registry Platform, ClinicalTrials.gov, and reference lists of included studies. We imposed no restrictions by language or publication date.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) of non-drug, non-invasive interventions tested over at least four weeks, for lower limb muscle cramps in any group of people, except pregnant women. The primary outcome was cramp frequency. Secondary outcomes were cramp pain severity, cramp duration, health-related quality of life, quality of sleep, participation in activities of daily living, proportion of participants reporting lower limb muscle cramps, and adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials, assessed risk of bias, and cross-checked data extraction and analyses according to standard Cochrane procedures.

MAIN RESULTS

We included three trials, with 201 participants, all 50 years of age and older; none had neurological disease. All trials evaluated a form of stretching for lower limb muscle cramps. A combination of daily calf and hamstring stretching for six weeks may reduce the severity of night-time lower limb muscle cramps (measured on a 10 cm visual analogue scale (VAS) where 0 = no pain and 10 cm = worst pain imaginable) in people aged 55 years and older, compared to no intervention (mean difference (MD) -1.30, 95% confidence interval (CI) -1.74 to -0.86; 1 RCT, 80 participants; low-certainty evidence). The certainty of evidence was very low for cramp frequency (change in number of cramps per night from week zero to week six) comparing the stretching group and the no intervention group (MD -1.2, 95% CI -1.8 to -0.6; 80 participants; very low-certainty evidence). Calf stretching alone for 12 weeks may make little to no difference to the frequency of night-time lower limb muscle cramps in people aged 60 years and older (stretching group median number of cramps in the last four weeks (Md) 4, interquartile range (IQR) 8; N = 48; sham stretching group Md 3, IQR 7.63; N = 46) (U = 973.5, z = -0.995, P = 0.32, r = 0.10; 1 RCT, 94 participants; low-certainty evidence). This trial did not report cramp severity. The evidence is very uncertain about the effects of a combination of daily calf, quadriceps, and hamstring stretching on the frequency and severity of leg cramps in 50- to 60-year-old women with metabolic syndrome (N = 24). It was not possible to fully analyse the frequency data and the scale used to measure cramp severity is not validated. No study reported health-related quality of life, quality of sleep, or participation in activities of daily living. No participant in these three studies reported adverse events. The evidence for adverse events was of moderate certainty as the studies were too small to detect uncommon events. In two of the three studies, outcomes were at risk of recall bias, and tools used to measure outcomes were not validated. Due to limitations in study designs that led to risks of bias, and imprecise findings with wide CIs, we cannot be certain that findings of future studies will be similar to those presented in this review.

AUTHORS' CONCLUSIONS

A combination of daily calf and hamstring stretching for six weeks may reduce the severity of night-time lower limb muscle cramps in people aged 55 years and older, but the effect on cramp frequency is uncertain. Calf stretching alone compared to sham stretching for 12 weeks may make little or no difference to the frequency of night-time lower limb muscle cramps in people aged 60 years and older. The evidence is very uncertain about the effects of a combination of daily calf, quadriceps, and hamstring stretching on the frequency and severity of leg cramps in 50- to 60-year-old women with metabolic syndrome. Overall, use of unvalidated outcome measures and inconsistent diagnostic criteria make it difficult to compare the studies and apply findings to clinical practice. Given the prevalence and impact of lower limb muscle cramps, there is a pressing need to carefully evaluate many of the commonly recommended and emerging non-drug therapies in well-designed RCTs across all types of lower limb muscle cramps. A specific cramp outcome tool should be developed and validated for use in future research.

Interventions for leg cramps in pregnancy

BACKGROUND

Leg cramps are a common problem in pregnancy. Various interventions have been used to treat them, including drug, electrolyte and vitamin therapies, and non-drug therapies. This Cochrane Review is an update of a review first published in 2015.

OBJECTIVES

To assess the effectiveness and safety of different interventions for treating leg cramps in pregnancy.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (ICTRP) (25 September 2019), and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of any intervention for the treatment of leg cramps in pregnancy compared with placebo, no treatment or other treatments. Quinine was excluded for its known adverse effects. Cluster-RCTS were eligible for inclusion. Quasi-RCTs and cross-over studies were excluded.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy. The certainty of the evidence was assessed using the GRADE approach.

MAIN RESULTS

We included eight small studies (576 women). Frequency of leg cramps was our primary outcome and secondary outcomes included intensity and duration of leg cramps, adverse outcomes for mother and baby and health-related quality of life. Overall, the studies were at low or unclear risk of bias. Outcomes were reported in different ways, precluding the use of meta-analysis and thus data were limited to single trials. Certainty of evidence was assessed as either low or very-low due to serious limitations in study design and imprecision. Oral magnesium versus placebo/no treatment The results for frequency of leg cramps were inconsistent. In one study, results indicated that women may be more likely to report never having any leg cramps after treatment (risk ratio (RR) 5.66, 95% confidence interval (CI) 1.35 to 23.68, 1 trial, 69 women, low-certainty evidence); whilst fewer women may report having twice-weekly leg cramps (RR 0.29, 95% CI 0.11 to 0.80, 1 trial, 69 women); and more women may report a 50% reduction in number of leg cramps after treatment (RR 1.42, 95% CI 1.09 to 1.86, 1 trial, 86 women, low-certainty evidence). However, other findings indicated that magnesium may make little to no difference in the frequency of leg cramps during differing periods of treatment. For pain intensity, again results were inconsistent. Findings indicated that magnesium may make little or no difference: mean total pain score (MD 1.80, 95% CI -3.10 to 6.70, 1 trial, 38 women, low-certainty evidence). In another study the evidence was very uncertain about the effects of magnesium on pain intensity as measured in terms of a 50% reduction in pain. Findings from another study indicated that magnesium may reduce pain intensity according to a visual analogue scale (MD -17.50, 95% CI -34.68 to -0.32,1 trial, 69 women, low-certainty evidence). For all other outcomes examined there may be little or no difference: duration of leg cramps (low to very-low certainty); composite outcome - symptoms of leg cramps (very-low certainty); and for any side effects, including nausea and diarrhoea (low certainty). Oral calcium versus placebo/no treatment The evidence is unclear about the effect of calcium supplements on frequency of leg cramps because the certainty was found to be very low: no leg cramps after treatment (RR 8.59, 95% CI 1.19 to 62.07, 1 study, 43 women, very low-certainty evidence). In another small study, the findings indicated that the mean frequency of leg cramps may be slightly lower with oral calcium (MD -0.53, 95% CI -0.72 to -0.34; 1 study, 60 women; low certainty). Oral vitamin B versus no treatment One small trial, did not report on frequency of leg cramps individually, but showed that oral vitamin B supplements may reduce the frequency and intensity (composite outcome) of leg cramps (RR 0.29, 95% CI 0.11 to 0.73; 1 study, 42 women). There were no data on side effects. Oral calcium versus oral vitamin C The evidence is very uncertain about the effect of calcium on frequency of leg cramps after treatment compared with vitamin C (RR 1.33, 95% CI 0.53 to 3.38, 1 study, 60 women, very low-certainty evidence). Oral vitamin D versus placebo One trial (84 women) found vitamin D may make little or no difference to frequency of leg cramps compared with placebo at three weeks (MD 2.06, 95% CI 0.58 to 3.54); or six weeks after treatment (MD 1.53, 95% CI 0.12 to 2.94). Oral calcium-vitamin D versus placebo One trial (84 women) found oral calcium-vitamin D may make little or no difference to frequency of leg cramps compared with placebo after treatment at three weeks (MD -0.30, 95% CI -1.55 to 0.95); and six weeks (MD 0.03, 95% CI -1.3 to 1.36). Oral calcium-vitamin D versus vitamin D One trial (84 women) found oral calcium-vitamin D may make little or no difference to frequency of leg cramps compared with vitamin D after treatment at three weeks (MD -1.35, 95% CI -2.84 to 0.14); and six weeks after treatment (MD -1.10, 95% CI -2.69 to 0.49).

AUTHORS' CONCLUSIONS

It is unclear from the evidence reviewed whether any of the interventions provide an effective treatment for leg cramps. This is primarily due to outcomes being measured and reported in different, incomparable ways so that data could not be pooled. The certainty of evidence was found to be low or very-low due to design limitations and trials being too small to address the question satisfactorily. Adverse outcomes were not reported, other than side effects for magnesium versus placebo/no treatment. It is therefore not possible to assess the safety of these interventions. The inconsistency in the measurement and reporting of outcomes meant that meta-analyses could not be carried out. The development of a core outcome set for measuring the frequency, intensity and duration of leg cramps would address these inconsistencies and mean these outcomes could be investigated effectively in the future.

Association between physical activity and Nocturnal Leg Cramps in patients over 60 years old: a case-control study

Nocturnal Legs Cramps are a frequent disorder, which have a negative impact on quality of life, particularly among patients over 60 years old. Lifestyle factors such as alcohol consumption have been shown to be associated with Nocturnal Leg Cramps. This study aimed to explore the association between nocturnal leg cramps and a sedentary lifestyle among elderly patients. A case-control study was conducted with a Bayesian approach for sensitivity analysis. Patients over 60 years old consulting their family doctor were recruited in the Alsace region, France. Cases were matched with controls free from cramps for age, sex, medical history and medications known to trigger cramps. The level of physical activity was assessed using the Dijon Physical Activity Score (DPAS). We performed univariate and multivariate analyses adjusting for alcohol consumption. 272 participants were matched into 136 pairs. 11% of all were sedentary persons. Adjusting for alcohol consumption, we observed an association between Nocturnal Leg Cramps and a sedentary lifestyle OR = 9.84 (95% credibility interval [1.74; 101.9]; posterior probability 99.68%). Our findings represent an additional argument to promote physical activity to patients over 60 years old. They also highlight the need to develop and evaluate physical activity interventions in the treatment of Nocturnal Legs Cramps.

Association Between Alcohol Consumption and Nocturnal Leg Cramps in Patients Over 60 Years Old: A Case-Control Study

PURPOSE

Nocturnal leg cramps are a specific kind of cramps affecting almost one-half of patients aged 60 years and older. They reduce patients' quality of sleep and have a negative impact on their quality of life. The aim of this study was to evaluate the association between nocturnal leg cramps and the consumption of alcoholic beverages in patients aged 60 years and older attending general practices.

METHODS

Case-control study with a Bayesian approach for sensitivity analysis. Participants were voluntary ambulatory patients aged 60 years and older consulting their family doctor. They were recruited in 67 general practices across the Alsace region. Cases (patients having cramps), were matched with controls (patients free from cramps) for age, sex, medical history, and medications known to trigger cramps. Alcohol consumption was assessed through a standardized food frequency questionnaire.

RESULTS

We found an association between the global consumption of alcoholic beverages and nocturnal leg cramps (OR = 6.5, 95% credibility interval, 1.68-38.05; posterior probability 99.82%).

CONCLUSION

We identified an association between alcohol consumption and nocturnal leg cramps among patients aged 60 years and older attending general practices. These findings have implications for the prevention of cramps.

Health technology assessment of magnet therapy for relieving pain

Background: Magnet therapy has been used increasingly as a new method to alleviate pain. Magnetic products are marketed with claims of effectiveness for reducing pain of various origins. However, there are inconsistent results from a limited number of randomized controlled trials (RCTs) testing the analgesic efficacy of magnet therapy. This study aimed to evaluate the safety and effectiveness of magnet therapy on reliving various types of pain. Methods: A systematic search of two main medical databases (Cochrane Library and Ovid Medline) was conducted from 1946 to May 2014. Only English systematic reviews that compared magnet therapy with other conventional treatments in patients with local pain in terms of pain relieving measures were included. The results of the included studies were thematically synthesized. Results: Eight studies were included. Magnet therapy could be used to alleviate pain of various origins including pain in various organs, arthritis, myofascial muscle pain, lower limb muscle cramps, carpal tunnel syndrome and pelvic pain. Results showed that the effectiveness of magnetic therapy was only approved in muscle pains, but its effectiveness in other indications and its application as a complementary treatment have not been established. Conclusion: According to the results, it seems that magnet therapy could not be an effective treatment for relieving different types of pain. Our results highlighted the need for further investigations to be done in order to support any recommendations about this technology.

Prevalence of cramps in patients over the age of 60 in primary care : a cross sectional study

Background

Cramps are involuntary painful muscle contractions that mainly affect older people. Cramps may cause severe pain and sleep disturbance. Little information exists on the prevalence and the main features of cramps in primary care settings. The objective of this study was to estimate the prevalence and the main features of cramps among primary care patients aged 60 years and older.

Methods

We prospectively enrolled 516 patients aged 60 years and older in a cross-sectional study at 25 general practices in Alsace – France between October 2011 and March 2012. Questionnaires were used to obtain information about demographics, cramp presence and main features, medical history, and treatment.

Results

The adjusted prevalence was 46 % (95 % CI: 38–53 %). Thirty-one per cent of the study sample reported being woken up by cramps, 15 % had cramps more than 3 times a month. Logistic regression revealed a slightly higher prevalence in the age group 65–69 years compared to 60–64 years. No significant association was observed between other age groups and prevalence, or between gender and prevalence. The main localization of cramps was in the calves (80 %). The duration since onset was 5 years or more for 58 %.

Conclusions

Cramps are common in primary care, and although only a minority of patients report suffering from cramps more than once a week, many patients report cramp-related sleep disturbance. Further studies are needed to assess risk factors and therapeutic options for patients suffering from cramps in primary care.

Electronic supplementary material

The online version of this article (doi:10.1186/s12875-016-0509-9) contains supplementary material, which is available to authorized users.

Characterization and Management of Hedgehog Pathway Inhibitor-Related Adverse Events in Patients With Advanced Basal Cell Carcinoma

Abnormal activation of hedgehog pathway signaling is a key driver in the pathogenesis of basal cell carcinoma (BCC). Vismodegib, a first-in-class small-molecule inhibitor of hedgehog pathway signaling, is approved by regulatory authorities for the treatment of adults who have metastatic BCC or locally advanced BCC that has recurred after surgery, or who are not candidates for surgery and who are not candidates for radiation. A second inhibitor, sonidegib, was also recently approved for the same patient group with locally advanced BCC. Adverse events (AEs) commonly observed in hedgehog pathway inhibitor (HPI)-treated patients include muscle spasms, ageusia/dysgeusia, alopecia, weight loss, and asthenia (fatigue). These AEs are thought to be mechanistically related to inhibition of the hedgehog pathway in normal tissue. Although the severity of the majority of AEs associated with HPIs is grade 1-2, the long-term nature of these AEs can lead to decreased quality of life, treatment interruption, and in some cases discontinuation, all of which might affect clinical outcome. The incidence, clinical presentation, putative mechanisms, and management strategies for AEs related to HPIs in advanced BCC are described. These observations represent the first step toward the development of mechanism-based preventive and management strategies. Knowledge of these AEs will allow health care professionals to provide appropriate counseling and supportive care interventions, all of which will contribute to improved quality of life and optimal benefit from therapy.

IMPLICATIONS FOR PRACTICE

The hedgehog pathway inhibitors (HPIs) vismodegib and sonidegib represent a therapeutic breakthrough for patients with advanced basal cell carcinoma. However, the nature of the low-grade adverse events (AEs) commonly observed in HPI-treated patients, including muscle spasms, ageusia/dysgeusia, alopecia, weight loss, and fatigue, can impact clinical outcomes as a result of decreased quality of life and treatment discontinuation. The incidence, clinical presentation, putative mechanisms, and management strategies for AEs related to administration of HPIs are described, with the goal of enabling health care professionals to provide appropriate counseling and supportive care interventions to their patients.

Are Electrically Induced Muscle Cramps Able to Increase the Cramp Threshold Frequency, When Induced Once a Week?

The cramp threshold frequency (CTF) is known to be positively correlated with the individual cramp susceptibility. Here we assessed CTF changes after two bouts of electrically induced muscle cramps (EIMCs). The EIMCs (6×5 sec) were unilaterally induced twice (separated by one week) in the gastrocnemius of an intervention group (n=8), while 5 participants served as control. The CTF increased from 25.1±4.6 Hz at baseline to 31.4±9.0 Hz and 31.7±8.5 Hz 24 h after bout 1 and 2 (P<0.05). Thereafter, the CTF declined following both bouts to reach values of 28.0±6.7 Hz and 29.1±7.7 Hz after 72 h after bout 1 and 2. Creatine kinase (CK) activity and perceived discomfort during cramps was lower after bout 2 (P<0.05). CTF, CK, and discomfort did not change in CG. That is, a single bout of EIMCs induces a 24 h CTF increment and a second bout sustains this effect, while perceived discomfort and muscle damage decreases. This short term effect may help athletes to reduce the cramp susceptibility for an important match.

Treatment of nocturnal leg cramps by blockade of the medial branch of the deep peroneal nerve after lumbar spine surgery

INTRODUCTION

Patients with lumbar spine disease sometimes complain of nocturnal leg cramps. We sought to investigate the effectiveness of blocking the medial branch of the deep peroneal nerve as treatment for nocturnal leg cramps after spinal surgery for lumbar spine disease.

METHODS

We evaluated 66 postoperative patients in this prospective comparative study of a group of patients with a nerve block (n = 41) and a control group without (n = 25). In the block group, the medial branch of the deep peroneal nerve was blocked at the distal two-thirds of the interspace between the first and second metatarsals using 5.0 mL of 1.0% lidocaine.

RESULTS

Two weeks after the block, the frequency of nocturnal leg cramps was reduced to less than a quarter of pretreatment baseline frequency in 61.0% of patients (n = 25) and less than half in 80.5% (n = 33). In the control group, the frequency of the leg cramps was reduced from baseline in 32.0% of patients (n = 8), and was unchanged or increased in 68.0% (n = 17) at 2 weeks. Cramp frequency was reduced to less than a quarter or less than half of baseline frequency in a significantly (P < 0.05 and P < 0.01, respectively) larger percentage of patients in the block group. The severity of each cramp was less in about two-thirds of patients (63.4%; n = 26) in the block group and was unchanged in one-third (31.7%; n = 13).

CONCLUSIONS

Blocking the medial branch of the peroneal nerve can be an effective, long-lasting, and simple treatment with low risk for nocturnal cramps sustained after lumbar spine surgery.

Interventions for leg cramps in pregnancy

BACKGROUND

Leg cramps are a common problem in pregnancy. Various interventions have been used to treat them, including drug, electrolyte and vitamin therapies, and non-drug therapies.

OBJECTIVES

To assess the effectiveness and safety of different interventions for treating leg cramps in pregnancy.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Register (31 March 2015) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of any intervention (drug, electrolyte, vitamin or non-drug therapies) for treatment of leg cramps in pregnancy compared with placebo, no treatment or other treatment. Quinine was excluded for its known adverse effects (teratogenicity). Cluster-RCTS were considered for inclusion. Quasi-RCTs and cross-over studies were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy.

MAIN RESULTS

We included six studies (390 women). Four trials compared oral magnesium with placebo/no treatment, two compared oral calcium with no treatment, one compared oral vitamin B versus no treatment, and one compared oral calcium with oral vitamin C. Two of the trials were well-conducted and reported, the other four had design limitations. The process of random allocation was sub-optimal in three studies, and blinding was not attempted in two. Outcomes were reported in different ways, precluding the use of meta-analysis and limiting the strength of our conclusions.The 'no treatment' group in one four-arm trial has been used as the comparison group for the composite outcome (intensity and frequency of leg cramps) in magnesium, calcium, and vitamin B versus no treatment. This gives it disproportionate weight in the overall analysis, thus interpretation of these results should be cautious. Oral magnesium versus placebo/no treatmentMagnesium (taken orally for two to four weeks) did not consistently reduce the frequency of leg cramps compared with placebo or no treatment. Outcomes that showed differences were: frequency of leg cramps after treatment: never, and twice a week (risk ratio (RR) 5.66, 95% confidence interval (CI) 1.35 to 23.68, one trial, 69 women, evidence graded low; RR 0.29, 95% CI 0.11 to 0.80, one trial, 69 women), and frequency of leg cramps: 50% reduction in number of leg cramps after treatment (RR 1.42, 95% CI 1.09 to 1.86, one trial, 86 women, evidence graded low). The outcomes that showed no difference were: frequency of leg cramps during two weeks of treatment (mean difference (MD) 1.80, 95% CI -1.32 to 4.92, one trial, 38 women, evidence graded low); frequency of leg cramps after treatment: daily, every other day, and once a week (RR 1.20, 95% CI 0.45 to 3.21, one trial, 69 women; RR 0.44, 95% CI 0.12 to 1.57, one trial, 69 women; RR 1.54, 95% CI 0.62 to 3.87, one trial, 69 women).Evidence about whether magnesium supplements reduced the intensity of pain was inconclusive, with two studies showing that it may slightly reduce pain, while one showed no difference. There were no differences in the experience of side effects (including nausea, flatulence, diarrhoea and intestinal air) between pregnant women receiving magnesium compared with placebo/no treatment. Oral calcium versus no treatmentA greater proportion of women receiving calcium supplements experienced no leg cramps after treatment than those receiving no treatment (frequency of leg cramps after treatment: never RR 8.59, 95% CI 1.19 to 62.07, one study, 43 women, evidence graded very low). There was no difference between groups for a composite outcome (intensity and frequency) for partial improvement (RR 0.64, 95% CI 0.36 to 1.15, one trial, 42 women); however, the same trial showed a greater proportion of women experiencing no leg cramps after treatment with calcium compared with no treatment (RR 5.50, 95% CI 1.38 to 21.86).Other secondary outcomes, including side effects, were not reported. Oral vitamin B versus no treatment Frequency of leg cramps was not reported in the one included trial. According to a composite outcome (frequency and intensity), more women receiving vitamin B fully recovered compared with those receiving no treatment (RR 7.50, 95% CI 1.95 to 28.81). Those women receiving no treatment were more likely to experience a partial improvement in the intensity and frequency of leg cramps than those taking vitamin B (RR 0.29, 95% CI 0.11 to 0.73, one trial, 42 women), or to see no change in their condition. However, these results are based on one small study with design limitations.Other secondary outcomes, including side effects, were not reported. Oral calcium versus oral vitamin CThere was no difference in the frequency of leg cramps after treatment with calcium versus vitamin C (RR 1.33, 95% CI 0.53 to 3.38, one study, 60 women, evidence graded very low). Other outcomes, includingside effects, were not reported.

AUTHORS' CONCLUSIONS

It is unclear from the evidence reviewed whether any of the interventions (oral magnesium, oral calcium, oral vitamin B or oral vitamin C) provide an effective treatment for leg cramps. This is primarily due to outcomes being measured and reported in different, incomparable ways, and design limitations compromising the quality of the evidence (the level of evidence was graded low or very low). This was mainly due to poor study design and trials being too small to address the question satisfactorily.Adverse outcomes were not reported, other than side effects for magnesium versus placebo/no treatment. It is therefore not possible to assess the safety of these interventions.The inconsistency in the measurement and reporting of outcomes, meant that data could not be pooled, meta-analyses could not be carried out, and comparisons between studies are difficult.The review only identified trials of oral interventions (magnesium, calcium, vitamin B or vitamin C) to treat leg cramps in pregnancy. None of the trials considered non-drug therapies, for example, muscle stretching, massage, relaxation, heat therapy, and dorsiflexion of the foot. This limits the completeness and applicability of the evidence.Standardised measures for assessing the frequency, intensity and duration of leg cramps to be used in large well-conducted randomised controlled trials are needed to answer this question. Trials of non-drug therapies are also needed.

Electrically induced muscle cramps induce hypertrophy of calf muscles in healthy adults

OBJECTIVES

Skeletal muscles usually cramp at short lengths, where the tension that can be exerted by muscle fibers is low. Since high tension is an important anabolic stimulus, it is questionable if cramps can induce hypertrophy and strength gains. In the present study we investigated if electrically induced cramps (EIMCs) can elicit these adaptations.

METHODS

15 healthy male adults were randomly assigned to an intervention (IG; n=10) and a control group (CG; n=5). The cramp protocol (CP) applied twice a week to one leg of the IG, consisted of 3x6 EIMCs, of 5 s each. Calf muscles of the opposite leg were stimulated equally, but were hindered from cramping by fixating the ankle at 0° plantar flexion (nCP).

RESULTS

After six weeks, the cross sectional area of the triceps surae was similarly increased in both the CP (+9.0±3.4%) and the nCP (+6.8±3.7%). By contrast, force of maximal voluntary contractions, measured at 0° and 30° plantar flexion, increased significantly only in nCP (0°: +8.5±8.8%; 30°: 11.7±13.7%).

CONCLUSION

The present data indicate that muscle cramps can induce hypertrophy in calf muscles, though lacking high tension as an important anabolic stimulus.

Quinine for muscle cramps

BACKGROUND

Muscle cramps can occur anywhere and for many reasons. Quinine has been used to treat cramps of all causes. However, controversy continues about its efficacy and safety. This review was first published in 2010 and searches were updated in 2014.

OBJECTIVES

To assess the efficacy and safety of quinine-based agents in treating muscle cramps.

SEARCH METHODS

On 27 October 2014 we searched the Cochrane Neuromuscular Disease Group Specialized Register, CENTRAL, MEDLINE and EMBASE. We searched reference lists of articles up to 2014. We also searched for ongoing trials in November 2014.

SELECTION CRITERIA

Randomised controlled trials of people of all ages with muscle cramps in any location and of any cause, treated with quinine or its derivatives.

DATA COLLECTION AND ANALYSIS

Three review authors independently selected trials for inclusion, assessed risk of bias and extracted data. We contacted study authors for additional information. For comparisons including more than one trial, we assessed the quality of the evidence using Grading of Recommendations Assessment, Development and Evaluation (GRADE).

MAIN RESULTS

We identified 23 trials with a total of 1586 participants. Fifty-eight per cent of these participants were from five unpublished studies. Quinine was compared to placebo (20 trials, n = 1140), vitamin E (four trials, n = 543), a quinine-vitamin E combination (three trials, n = 510), a quinine-theophylline combination (one trial, n = 77), and xylocaine injections into the gastrocnemius muscle (one trial, n = 24). The most commonly used quinine dosage was 300 mg/day (range 200 to 500 mg). We found no new trials for inclusion when searches were updated in 2014.The risk of bias in the trials varied considerably. All 23 trials claimed to be randomised, but only a minority described randomisation and allocation concealment adequately.Compared to placebo, quinine significantly reduced cramp number over two weeks by 28%, cramp intensity by 10%, and cramp days by 20%. Cramp duration was not significantly affected.A significantly greater number of people suffered minor adverse events on quinine than placebo (risk difference (RD) 3%, 95% confidence interval (CI) 0% to 6%), mainly gastrointestinal symptoms. Overdoses of quinine have been reported elsewhere to cause potentially fatal adverse effects, but in the included trials there was no significant difference in major adverse events compared with placebo (RD 0%, 95% CI -1% to 2%). One participant suffered from thrombocytopenia (0.12% risk) on quinine.A quinine-vitamin E combination, vitamin E alone, and xylocaine injections into gastrocnemius were not significantly different to quinine across all outcomes, including adverse effects. Based on a single trial comparison, quinine alone was significantly less effective than a quinine-theophylline combination but with no significant differences in adverse events.

AUTHORS' CONCLUSIONS

There is low quality evidence that quinine (200 mg to 500 mg daily) significantly reduces cramp number and cramp days and moderate quality evidence that quinine reduces cramp intensity. There is moderate quality evidence that with use up to 60 days, the incidence of serious adverse events is not significantly greater than for placebo in the identified trials, but because serious adverse events can be rarely fatal, in some countries prescription of quinine is severely restricted.Evidence from single trials suggests that theophylline combined with quinine improves cramps more than quinine alone, and the effects of xylocaine injections into gastrocnemius are not significantly different to quinine across all outcomes. Low or moderate quality evidence shows no significant difference between quinine and vitamin E or quinine and quinine-vitamin E mixture. Further research into these alternatives, as well other pharmacological and non-pharmacological treatments, is thus warranted.There is no evidence to judge optimal dosage or duration of quinine treatment. Further studies using different dosages and measurement of serum quinine levels will allow a therapeutic range to be defined for muscle cramp. Because serious adverse events are not common, large population studies are required to more accurately inform incidence. Longer lengths of follow-up in future trials will help determine the duration of action following cessation of quinine as well as long-term adverse events. The search for new therapies, pharmacological and nonpharmacological, should continue and further trials should compare vitamin E, quinine-vitamin E combination, and quinine-theophylline mixture with quinine.

Prospective study of muscle cramps in Charcot-Marie-tooth disease

INTRODUCTION

This study aims to assess the frequency, location, severity, duration, and fluctuation over time of muscle cramps in Charcot-Marie-Tooth disease (CMT).

METHODS

Inherited Neuropathies Consortium Contact Registry participants recorded the occurrence and characteristics of muscle cramps using an 11-question survey administered 3 times over 8 weeks.

RESULTS

A total of 110 adult patients with CMT completed the survey. Weekly cramp frequency was 9.3 (SD 12.3), and 23% had daily muscle cramps. Twenty-two percent reported a significant impact on quality of life. Over 8 weeks, the daily frequency and severity of muscle cramps did not change significantly.

CONCLUSIONS

Patients with CMT have muscle cramps that vary little over an 8-week period, and they may interfere with quality of life. These data may be useful in the planning of clinical trials of agents to treat adults with CMT-associated muscle cramps.

Leg discomfort: beyond the joints

Although simple characterization of discomfort as cramps, heaviness, shooting pains, and so forth can be misleading, history and examination are key to accurate diagnosis. Absence of both dorsalis pedis and posterior tibial pulses strongly suggests peripheral arterial disease (PAD), and the presence of either pulse makes PAD less likely. Hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) are a common cause of lower extremity myalgias. Restless legs syndrome causes nocturnal discomfort but must be distinguished from confounding“mimics." Neurologic causes of leg symptoms include lumbar spinal stenosis, radiculopathy, distal symmetric polyneuropathy, and entrapment neuropathy. Many common causes of leg discomfort can be managed conservatively.

A promising approach to effectively reduce cramp susceptibility in human muscles: a randomized, controlled clinical trial

Background

To investigate if the cramp threshold frequency (CTF) can be altered by electrical muscle stimulation in a shortened position.

Methods

A total of 15 healthy male sport students were randomly allocated to an intervention (IG, n = 10) and a non-treatment control group (CG, n = 5). Calf muscles of both legs in the IG were stimulated equally twice a week over 6 weeks. The protocol was 3×5 s on, 10 s off, 150 µs impulse width, 30 Hz above the individual CTF, and was at 85% of the maximal tolerated stimulation energy. One leg was stimulated in a shortened position, inducing muscle cramps (CT), while the opposite leg was fixated in a neutral position at the ankle, hindering muscle cramps (nCT). CTF tests were performed prior to the first and 96 h after the 6^th (3 w) and 12^th (6 w) training session.

Results

After 3 w, the CTF had significantly (p<0.001) increased in CT calves from 23.3±5.7 Hz to 33.3±6.9 Hz, while it remained unchanged in nCT (pre: 23.6±5.7 Hz, mid: 22.3±3.5 Hz) and in both legs of the CG (pre: 21.8±3.2 Hz, mid: 22.0±2.7 Hz). Only CT saw further insignificant increases in the CTF. The applied stimulation energy (mA² • µs) positively correlated with the effect on the CTF (r = 0.92; p<0.001).

Conclusions

The present study may be useful for developing new non-pharmacological strategies to reduce cramp susceptibility.

Trial Registry

German Clinical Trials Register DRKS00005312

Unknotting night-time muscle cramp: a survey of patient experience, help-seeking behaviour and perceived treatment effectiveness

BACKGROUND

Night-time calf cramping affects approximately 1 in 3 adults. The aim of this study was to explore the experience of night-time calf cramp; if and where people seek treatment advice; and perceived treatment effectiveness.

METHODS

80 adults who experienced night-time calf cramp at least once per week were recruited from the Hunter region, NSW, Australia through newspaper, radio and television advertisements. All participants completed a pilot-tested survey about muscle cramp. Quantitative data were analysed with independent-sample t-tests, Chi square tests and Fisher's tests. Qualitative data were transcribed and sorted into categories to identify themes.

RESULTS

Median recalled age of first night-time calf cramp was 50 years. Most participants recalled being awoken from sleep by cramping, and experiencing cramping of either calf muscle, calf-muscle soreness in the days following cramp and cramping during day-time. Despite current therapies, mean usual pain intensity was 66 mm on a 100 mm visual analogue scale. Participants described their cramps as being 'unbearable', 'unmanageable' and 'cruel'. One participant stated that 'sometimes I just wish I could cut my legs open' and another reported 'getting about 2 h sleep a night due to cramps'. Most participants had sought advice about their night-time calf cramps from a health professional. Participants identified 49 different interventions used to prevent night-time calf cramp. Of all treatment ratings, 68% described the intervention used to prevent cramp as being 'useless' or of 'a little help'. Of 14 participants who provided additional information regarding their use of quinine, eight had a current prescription of quinine for muscle cramp at the time of the survey. None had been asked by their prescribing doctor to stop using quinine.

CONCLUSION

Night time calf cramps typically woke sufferers from sleep, affected either leg and caused ongoing pain. Most participants experienced little or no relief with current therapies used to prevent muscle cramp. Most people who were taking quinine for muscle cramp were unaware that the Australian Therapeutic Goods Administration withdrew support of quinine for muscle cramp in 2004 due to the risk of thrombocytopaenia. Case-control studies are required to identify therapeutic targets so that clinical trials can evaluate safe interventions to prevent recurrent cramp.