Search

A 15-year-old girl arrived with her father. She reported experiencing discomfort and cramps in her right arm while writing for the past 3 months. Her father had observed a palpable lump medially in her right mid-arm. She mentioned variations in the size of the lump on occasion. She denied experiencing any notable pain in the lump., (© Journal of the Association of Physicians of India 2024.)

Introduction/aims: Muscle cramps are a common and often disabling symptom in amyotrophic lateral sclerosis (ALS), a devastating and incurable neurodegenerative disorder. To date, there are no medications specifically approved for the treatment of muscle cramps. Ameliorating muscle cramps in ALS may improve and sustain quality of life. A widely prescribed traditional Japanese (Kampo) medicine against muscle cramps, shakuyakukanzoto (TJ-68), has been studied in advanced liver disease, spinal stenosis, kidney failure, and diabetic neuropathy. The Japanese ALS Management Guideline mentions TJ-68 for difficult muscle cramps in ALS. Therefore, the rationale of our trial is to investigate the safety and effectiveness of TJ-68 in treating painful and disabling muscle cramps in people with ALS outside of Japan. Accordingly, we are conducting a randomized clinical trial to test the safety and efficacy of TJ-68 in participants with ALS reporting frequent muscle cramps using an innovative, personalized N-of-1 design. If successful, TJ-68 may be used for muscle cramps in a broader population of people with ALS., Methods: This is a two-site, double-blind, randomized personalized N-of-1 early clinical trial with TJ-68. At least 22 participants with ALS and daily muscle cramps will receive drug or placebo for 2 weeks (one treatment period) followed by a 1-week washout in a four-period cross-over design. While the primary objective is to evaluate the safety of TJ-68, the study has 85% power to detect a one-point shift on the Visual Analog Scale for Muscle Cramps Affecting Overall Daily Activity of the Columbia Muscle Cramp Scale (MCS). Secondary outcomes include the full MCS score, a Cramp Diary, Clinical Global Impression of Changes, Goal Attainment Scale, quality of life scale and ALS functional rating scale-revised (ALSFRS-R)., Discussion: The study is underway. A personalized N-of-1 trial design is an efficient approach to testing medications that alleviate muscle cramps in rare disorders. If TJ-68 proves safe and efficacious then it may be used to treat cramps in ALS, and help to improve and sustain quality of life., Trial Registration: This clinical trial has been registered with ClinicalTrials.gov (NCT04998305), 8/9/2021., (© 2023. The Author(s).)

Muscle cramps are painful, sudden, involuntary muscle contractions that are generally self-limiting. They are often part of the spectrum of normal human physiology and can be associated with a wide range of acquired and inherited causes. Cramps are only infrequently due to progressive systemic or neuromuscular diseases. Contractures can mimic cramps and are defined as shortenings of the muscle resulting in an inability of the muscle to relax normally, and are generally myogenic. General practitioners and neurologists frequently encounter patients with muscle cramps but more rarely those with contractures. The main questions for clinicians are: (1) Is this a muscle cramp, a contracture or a mimic? (2) Are the cramps exercise induced, idiopathic or symptomatic? (3) What is/are the presumed cause(s) of symptomatic muscle cramps or contractures? (4) What should be the diagnostic approach? and (5) How should we advise and treat patients with muscle cramps or contractures? We consider these questions and present a practical approach to muscle cramps and contractures, including their causes, pathophysiology and treatment options., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Competing Interests: None

Muscle cramps are very common and can reduce quality of life. There are multiple causes, including some physiological conditions, metabolic, endocrine, vascular disorders or neuromuscular diseases. Adequate management first requires differentiating cramps from other muscular phenomena. In most cases, the investigations are limited to a comprehensive history and clinical examination, but a biological, radiological and/or electrophysiological work-up may be useful. Treatment, when needed, is most often symptomatic and is unfortunately based on little evidence., Competing Interests: Les auteurs n’ont déclaré aucun conflit d’intérêts en relation avec cet article.

Fasciculations and cramps originate in the motor unit, a functional unit that includes the lower motor neuron and their innervated muscle fibres. Both are common complaints in outpatient practice. These symptoms can be secondary to neurological or medical pathology, presenting a broad differential diagnosis and a complex approach. Recent neurophysiological studies have increased the knowledge of their origin mainly in amyotrophic lateral sclerosis. The symptomatic management of fasciculations and cramps depends on their etiology and includes pharmacological and non-pharmacological treatments. This article aims to present an updated review of the most relevant aspects of physiopathology, clinical approach, and differential diagnosis of both phenomena.

Background: Leg cramps are painful sensations of tightening in the muscles of the legs that commonly appear during the night and are often associated with secondary insomnia. They are common especially in older age. There is no evidence that any method of prevention of nocturnal leg cramps is both safe and effective. There are no previous trials concerning cramp prevention by using compression stockings. The objective of this study is to assess in a prospective randomised controlled trial whether leg cramps can be prevented by the daily use of knee-length compression stockings or magnesium supplements., Methods: The study will be set in Finland, and 50-84-year-old volunteers will be recruited through Google Ads, the Finnish health library website and Finnish primary health care centres. The participants must have a minimum of two episodes of leg cramps per week for the past 4 weeks to be included in the study. The participants (n = 225) will be allocated to three equal groups: the compression stocking arm, the magnesium supplement arm and the placebo arm. The participants will go through 4 weeks of follow-up without intervention and then another 4 weeks of follow-up with the assigned intervention. The material for the study will be collected through electronic questionnaires., Discussion: This protocol describes a study that compares compression stockings, magnesium supplements and placebo for the prevention of leg cramps. The results of this study can significantly improve knowledge on the methods of preventing leg cramps., Trial Registration: ClinicalTrials.gov NCT04694417. Registered on Jan 4, 2021., (© 2021. The Author(s).)

Background: Inadequate refilling from extravascular compartments during hemodialysis can lead to intradialytic symptoms, such as hypotension, nausea, vomiting, and cramping/myalgia. Relative blood volume (RBV) plays an important role in adapting the ultrafiltration rate which in turn has a positive effect on intradialytic symptoms. It has been clinically challenging to identify changes RBV in real time to proactively intervene and reduce potential negative consequences of volume depletion. Leveraging advanced technologies to process large volumes of dialysis and machine data in real time and developing prediction models using machine learning (ML) is critical in identifying these signals., Method: We conducted a proof-of-concept analysis to retrospectively assess near real-time dialysis treatment data from in-center patients in six clinics using Optical Sensing Device (OSD), during December 2018 to August 2019. The goal of this analysis was to use real-time OSD data to predict if a patient's relative blood volume (RBV) decreases at a rate of at least - 6.5 % per hour within the next 15 min during a dialysis treatment, based on 10-second windows of data in the previous 15 min. A dashboard application was constructed to demonstrate how reporting structures may be developed to alert clinicians in real time of at-risk cases. Data was derived from three sources: (1) OSDs, (2) hemodialysis machines, and (3) patient electronic health records., Results: Treatment data from 616 in-center dialysis patients in the six clinics was curated into a big data store and fed into a Machine Learning (ML) model developed and deployed within the cloud. The threshold for classifying observations as positive or negative was set at 0.08. Precision for the model at this threshold was 0.33 and recall was 0.94. The area under the receiver operating curve (AUROC) for the ML model was 0.89 using test data., Conclusions: The findings from our proof-of concept analysis demonstrate the design of a cloud-based framework that can be used for making real-time predictions of events during dialysis treatments. Making real-time predictions has the potential to assist clinicians at the point of care during hemodialysis., (© 2021. The Author(s).)

This article reviews the evaluation of 4 vexing symptoms for elderly patients in primary care: leg cramps, dizziness, insomnia, and weight loss. For each, ideal evaluations are proposed., Competing Interests: Disclosure The authors have nothing to disclose., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Muscle cramps, defined as a painful contraction of a muscle or muscle group, are a common symptom most people have experienced throughout their lifespan. In some cases cramps can be frequent, severe, and disabling, thus requiring medical assessment and intervention. Physiologic states such as pregnancy and exercise are associated with excessive muscle cramps, as are numerous medical and neurologic conditions, medications such as diuretics and statins, and peripheral nerve hyperexcitability syndromes. Treatment options for muscle cramps are limited, although recent studies have shown that mexiletine could be a safe and efficient alternative for patients with amyotrophic lateral sclerosis., Competing Interests: Disclosure The author disclose that some of this work was supported by a New Initiatives grant from the Division of Neurology at the University of Toronto., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Muscle pain as a common symptom in daily practice frequently occurs as a non-specific accompanying symptom in multiple internal and neurological diseases. Primarily inflammatory or autoimmune muscular diseases are causing muscle pain. However, a number of non-inflammatory causes of pain can also be considered for differential diagnosis. These are presented in this article. In principle, a distinction must be made between focal and diffuse muscle pain. As an invasive diagnostic procedure, a muscle biopsy should only be performed as the last step in the diagnostic alogorithm. If diffuse muscle pain is only associated with slight muscle weakness or is completely absent, there is usually a primary rheumatic cause. Statins (HMG-CoA reductase inhibitors) can lead to rhabdomyolysis, muscle fiber atrophy and muscle necrosis by damaging the muscle fiber membrane. Myotonias are autosomal dominant or autosomal recessive inherited disorders of muscle function. The genetic defect leads to pronounced muscle stiffness. The cause of metabolic myopathies can be disorders of the carbohydrate, fat or purine metabolism. Fibromyalgia syndrome (FMS) is a non-inflammatory disease and, according to the current knowledge, recognized as the result of an exposure to physical, biological and psychosocial factors (biopsychological disease model). To help diagnosing FMS, pain regions and core symptoms (fatigue, sleep disturbances) can be detected using questionnaires (Widespread Pain Index [WPI] and Symptom Severity Scale [SSS])., Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

The present review focuses on the cramp-fasciculation syndrome, a benign disorder which is regarded as a hyperexcitability syndrome of the peripheral nervous system. The article presents clinical features, pathophysiology, differential diagnosis, therapy and a case report to illustrate the cramp-fasciculation-syndrome., Competing Interests: Die Autoren geben an, dass kein Interessenkonflikt besteht., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: There has been a small number of reports mention the clinical features including quality of life (QOL) in liver cirrhosis (LC) patients with muscle cramping and therapeutic efficacy for muscle cramping. We evaluated clinical features of muscle cramping and treatments in such patients., Patients and Methods: Two-hundred and eighty-nine LC outpatients (70.6 ± 10.5 years old; male: female = 149: 140) were questioned regarding the presence or absence of muscle cramps within the last 3 months, including frequency, severity of related pain using a visual analogue scale, cramp locations, time of day, duration, sleep disturbance, daily activity decline, and being conscious of QOL decline. At the next hospital-visit, 3 or 4 months later, the subjects, who treated with medical intervention, received the same questionnaire., Results: Patients with muscle cramps (n = 160) included a higher percentage of females (53.8 vs. 41.9%, P = 0.045), worse Child-Pugh score (5: 6: 7: 8: 9: 10 = 91: 36: 15: 10: 4: 4 vs. 85: 25: 12: 5: 0: 2, P = 0.043) and lower platelet count (10.2 ± 4.7 vs. 11.8 ± 5.0 × 104/µl, P = 0.006) as compared to those without cramps (n = 129). Of the 160 with cramping, 82 (51.3%), received treatment with several types of medication, with l-carnitine the most administered drug (n = 66: 80.5%), and those also showed a tendency to complain about muscle cramps at night, sleep disturbance, reduced daily activity, and being conscious of QOL decline (each P < 0.01). We observed that frequency, visual analogue scale, sleep disturbance, daily activity, duration of muscle cramping, and being conscious of QOL decline were improved after the intervention (each P < 0.001, respectively)., Conclusion: Intervention for muscle cramping improves total QOL in LC patients with such symptom.

Background: There is an urgent need for new therapeutic options to treat muscle cramps; however, no patient-reported measures exist that capture the entire cramp experience. We conducted a qualitative study to assess the experience of patients suffering muscle cramps, aiming to understand what factors determine the impact cramps have in patients' lives to guide the development of a patient-centered outcome measure of cramp severity and impact., Methods: We enrolled patients with cramps due to several etiologies, including motor neuron disease, pregnancy-induced cramps, cirrhosis and hemodialysis, and idiopathic and exercise-induced cramps. Patients participated in semistructured interviews about their experiences with muscle cramps and their responses were recorded and transcribed. Data were analyzed with content analysis using data saturation to determine the sample size. We subsequently developed a conceptual framework of cramp severity and overall cramp impact., Results: Ten patients were interviewed when data saturation was reached. The cramp experience was similar across disease and physiological states known to cause muscle cramps. The main themes that compose the overall cramp impact are cramp characteristics, sleep interference, daytime activities interference, and the effect on mental health., Conclusions: This framework will be used to develop a patient-reported outcome of cramp severity and impact.

Background: Throat pain is a common complaint in the emergency department. The related diagnoses are varied, from simple gastroesophageal reflux disease to catastrophic aortic dissection. This case highlights the importance of pertinent patient history and frequent reassessments in order to recognize the latter., Case Report: A 58-year-old woman was found to have a type A aortic dissection after initially presenting to the emergency department with a chief complaint of "burning" throat pain. Throughout the patient's evaluation in the emergency department, her symptoms evolved from the complaint of mild throat pain and water brash to development of chest pain and sudden right lower extremity cramping. Her history of hypertension, smoking, and a previous cerebral aneurysm prompted further intervention, including aggressive blood pressure control and emergent imaging. A computed tomography scan with angiography revealed the diagnosis of a type A aortic dissection. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: We highlight the importance of recognizing that patient presentation may change throughout the course of the emergency department stay, and that our case represents an atypical presentation of serious disease., (Copyright © 2019. Published by Elsevier Inc.)

Objective: To develop a novel muscle cramp scale (MCS) to assess frequency, severity and clinically meaningful information related to cramps among patients with amyotrophic lateral sclerosis (ALS). Methods: This new scale comprises four 5-point subdomains: (1) triggering factors, (2) frequency, (3) location, (4) severity, and (5) the degree to which cramps affect overall daily living. Thirty patients with ALS, who experienced at least 5 cramps per week, participated in a randomized test-retest study. An additional 26 patients participated in a second study assessing cramp changes over 4 weeks using the MCS and a detailed cramp diary. Results: To establish internal reliability of the scale, a Cronbach's coefficient value of 0.75 or higher was considered acceptable. Test/retest evaluations comparing in-person and telephone administration were assessed using paired t -tests and Cohen's kappa statistics. Non-significant differences were identified, and the results revealed moderate to high agreement for each item (range 0.60 to 0.95, p  < 0.0001). Scale construct validity against the cramp diary was acceptable. There were essentially no significant mean differences in muscle cramps over 4 weeks measured using the MCS and diary, respectively. Conclusions: The MCS is a valid, simple, and quick measure for the assessment of muscle cramps in patients with ALS. It can be reliably administered either in person or by telephone and provides richer information than the routinely utilized cramp diary.

Introduction: Muscle cramps are common comorbidities in chronic liver disease (CLD). Although the prevalence of these has been reported in patients with liver cirrhosis (LC), that of CLD is unknown. In this study, we aimed to clarify the prevalence and characteristics of muscle cramps in individual CLD., Patients and Methods: A total of 432 patients with CLD who visited our hospital were enrolled. The existence of muscle cramps, frequency, time zone, duration, and the degree of pain were investigated using a medical interview questionnaire., Results: The median age of the patients was 65 years and 48.6% of the patients were women. The prevalence of muscle cramps was 25.9%. Age, female sex, lower BMI, existence of comorbid diseases, and liver fibrosis were associated significantly with muscle cramps. In LC, muscle cramps were significantly frequent, and the severity and duration of these were significantly stronger and longer compared with chronic hepatitis. Female sex [odds ratio (OR): 2.26; P=0.014], diabetes (OR: 29.4; P<0.001), chronic kidney disease (OR: 8.33; P=0.004), and lower BMI (OR: 0.853; P<0.001) were independent factors associated with muscle cramps in CLD. Muscle mass indices were significantly lower among nonalcoholic fatty liver disease patients with muscle cramps, female patients, elderly patients, and patients with advanced fibrosis., Conclusion: The prevalence of muscle cramps was relatively high in CLD. Female sex, comorbid diabetes, and chronic kidney disease are associated with muscle cramps in CLD. Furthermore, reduced muscle mass is related to muscle cramps in nonalcoholic fatty liver disease.

Purpose: To determine whether quantitative methods could separate golfers with a possible dystonic cause of the "yips" from those that appear to be nondystonic., Methods: Twenty-seven golfers completed 10 two-handed and 10 right hand-only putts. Surface EMG assessed forearm muscle co-contraction and motion detectors monitored wrist and putter movements. Based on a videotape review, golfers were grouped into those with yips of dystonic etiology, those with the yips nondystonic, and those with no yips., Results: On video review of two-handed putting, five golfers had yips that appeared to be dystonic, nine had yips that did not appear to be dystonic, and 13 had no yips. During two-handed putting co-occurrence of a yipped putt and wrist flexor/extensor and/or pronator/supinator co-contraction was significantly more frequent in those with dystonic yips. The dystonic group had no increase in the number of yipped putts or yips with co-contraction when putting right hand only, whereas the nondystonic group had significantly more yipped putts and more yipped putts with co-contraction with right hand only., Conclusions: Quantitative methods were identified that appear to identify golfers with a dystonic etiology for the yips. It is not just the frequency of yips nor just specific motion patterns alone, rather it is also a combination of yips with co-occurring co-contraction when putting with two hands, and then right hand only, that distinguished this possible etiology. Despite being a small study, identifying a dystonic pattern, even in a nonpressure indoor setting, may aid in assessment and possible monitoring of treatment.

Objectives: To explore the correlations between different muscle cramp characteristics including cramp frequency and severity and clinical and large and small nerve fiber measures in patients with diabetes type 1 (DM 1) and 2 (DM 2)., Methods: Prospective cross sectional study of healthy controls and patients with DM 1 and DM 2 recruited between April 2009 and November 2012. Participants underwent clinical evaluation and large and small nerve fiber studies, and the frequency and correlations of muscle cramps were explored., Results: 37 controls, 51 patients with DM 1, and 69 patients with DM 2 were studied. Muscle cramps were the most frequent symptom captured by the Toronto Clinical Neuropathy Score (TCNS) in all groups, up to 78% in patients with DM 2. In patients with DM 1, but not DM 2, muscle cramp frequency and severity were correlated with clinical (TCNS) and both large (electrophysiology and vibration perception thresholds) and small nerve fiber measures., Conclusions: Muscle cramps are frequent in diabetes and are correlated with clinical and both small and large nerve fiber measures in DM 1, suggesting that their origin and propagation might extend beyond the motor nerve., Significance: Muscle cramps correlate with nerve fiber measures in DM 1., (Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Introduction: Muscle cramping may increase peripheral nervous system excitability. It is unknown if, and how long, cramp susceptibility is affected by previous cramping. We tested whether volitionally induced muscle cramps (VIMCs) lowered cramp threshold frequency (TF c ) and how long TF c was affected post-VIMC., Methods: Fifteen cramp-prone participants volitionally induced a flexor hallucis brevis (FHB) cramp on 4 separate days. FHB TF c was measured before VIMC (i.e., baseline) and 5, 30, and 60 min post-VIMC. VIMC electromyography (EMG) amplitude, VIMC duration, and perceived VIMC intensity were measured to ensure consistency of VIMC between days., Results: VIMC EMG amplitude, duration, and perceived intensity were similar between days (P > 0.05). VIMC lowered TF c ; baseline TF c (18 ± 6 Hz) was higher than 5-min (14 ± 6 Hz), 30-min (14 ± 5 Hz), and 60-min TF c (14 ± 5 Hz; P < 0.05)., Discussion: Acute VIMCs increase cramp susceptibility. Clinicians should apply treatments for at least 60 min postcramp to decrease the probability of cramp recurrence. Muscle Nerve 56: E95-E99, 2017., (© 2017 Wiley Periodicals, Inc.)

Unilateral multiple adrenocortical micronodules (UMNs) constitute a rare subset of primary aldosteronism (PA) characterized by the hypersecretion of aldosterone derived from multiple small nodules in the zona glomerulosa of the unilateral adrenal grand. This case study describes a 49-year-old man with PA and UMNs who presented with muscle cramps at rest due to hypokalemia. The patient had a 6-year history of hypertension treated with antihypertensive drugs. Imaging studies revealed bilateral adrenal nodules as large as 5 mm. Adrenal venous sampling confirmed unilateral PA; therefore, the patient underwent the removal of the affected adrenal gland. Macroscopically, the removed adrenal gland exhibited irregular adrenocortical thickening accompanied by ill-defined, adrenocortical macronodules as large as 6 mm. The zona glomerulosa was histologically hyperplastic. However, an immunohistochemistry test of the steroidogenic enzymes revealed that these macronodules and the hyperplastic glomerular layer tested negative for CYB11B2. Moreover, we observed adrenocortical micronodules as large as 0.5 mm that tested immunohistochemically positive for CYP11B2 and HSD3B2 but negative for CYP17A1 and CYP11B1. Thus, UMNs were diagnosed. This case instructively indicates that a grossly or histologically detectable nodular lesion is not necessarily a culprit lesion for PA. Therefore, functional histopathology is indispensable for the correct subclassification of PA., (© 2017 Japanese Society of Pathology and John Wiley & Sons Australia, Ltd.)

Background: Up to 33% of the general population over 50 years of age are affected by nocturnal leg cramps. Currently there are no generally accepted clinical characteristics, which identify nocturnal leg cramps. This study aims to identify these clinical characteristics and to differentiate between them and the characteristics of restless leg syndrome and periodic limb disorder., Method: A systematic literature study was executed from December 2015 to May 2016. This study comprised of a systematic literature review of randomized clinical trials, observational studies on nocturnal and rest cramps of legs and other muscles, and other systematic and narrative reviews. Two researchers independently extracted literature data and analyzed this using a standardized reviewing protocol. Modified versions of the Cochrane Collaboration tools assessed the risk of bias. A Delphi study was conducted to assess agreement on the characteristics of nocturnal leg cramps., Results: After systematic and manual searches, eight randomized trials and ten observational studies were included. On the basis of these we identified seven diagnostic characteristics of nocturnal leg cramps: intense pain, period of duration from seconds to maximum 10 minutes, location in calf or foot, location seldom in thigh or hamstrings, persistent subsequent pain, sleep disruption and distress., Conclusion: The seven above characteristics will enhance recognition of the condition, and help clinicians make a clear distinction between NLC and other sleep-related musculoskeletal disorder among older adults.

The objective of this study was to describe muscle cramps in an US sample of amyotrophic lateral sclerosis (ALS) patients. Utilizing an anonymous web based questionnaire we queried ALS patients regarding the severity, frequency, time-course, treatment of muscle cramps and their relationship to pain. The survey had 282 respondents with 92% reporting that they had cramps. For 20% of the sample, cramps were stated to be the presenting ALS symptom. Cramp severity was rated at a mean of 5.2/10 and the mean cramp frequency was 5.3 cramps per day. Cramp intensity and frequency did not correlate with duration or severity of ALS. Pain as measured with the Patient Reported Outcome Measurement Information System (PROMIS) pain scales was not statistically different from the US general population. Cramp severity and frequency significantly and positively correlated with the PROMIS pain scales. Patients with more severe cramps were more likely to use prescription medications for their cramps compared to patients with milder symptoms. Treatments directed at cramps were tried by 57%. In conclusion, cramps are a common symptom in ALS and it does not correlate with disease duration or severity. The severity of cramps is on average moderate and many patients try treatments.

Although exercise-associated muscle cramps (EAMC) are highly prevalent among athletic populations, the etiology and most effective management strategies are still unclear. The aims of this narrative review are 3-fold: (1) briefly summarize the evidence regarding EAMC etiology; (2) describe the risk factors and possible physiological mechanisms associated with neuromuscular fatigue and EAMC; and (3) report the current evidence regarding prevention of, and treatment for, EAMC. Based on the findings of several large prospective and experimental investigations, the available evidence indicates that EAMC is multifactorial in nature and stems from an imbalance between excitatory drive from muscle spindles and inhibitory drive from Golgi tendon organs to the alpha motor neurons rather than dehydration or electrolyte deficits. This imbalance is believed to stem from neuromuscular overload and fatigue. In concert with these findings, the most successful treatment for an acute bout of EAMC is stretching, whereas auspicious methods of prevention include efforts that delay exercise-induced fatigue. Muscle Nerve 54: 177-185, 2016., (© 2016 Wiley Periodicals, Inc.)

Clinical Scenario: Although exercise-associated muscle cramps (EAMC) are common in ultradistance runners and athletes in general, their etiology remains unclear. EAMC are painful, sudden, involuntary contractions of skeletal muscle occurring during or after exercise and are recognized by visible bulging or knotting of the whole, or part of, a muscle. Many clinicians believe EAMC occur after an imbalance in electrolyte concentrations, specifically serum sodium concentration ([Na+]s) and serum potassium concentration ([K+]s). Studies that have established a link between EAMC occurrence and serum electrolyte concentrations after an athletic event are unhelpful. Focused Clinical Question: Are [Na+]s and [K+]s different in athletes who experience EAMC than noncrampers?

Introduction: Muscle cramping is a common symptom in amyotrophic lateral sclerosis (ALS) that lacks efficacious treatment. The natural history of this symptom is unknown, which hampers efforts to design optimal clinical trials., Methods: We surveyed early stage ALS patients about their experience with cramps each month by phone for up to 21 months., Results: Cramps developed in 95% of patients over the course of their disease. The number of cramps experienced by an individual varied widely from month-to-month and trended lower after the first year of illness (P = 0.26). Those with limb-onset and age >60 years had more cramps than bulbar-onset (P < 0.0001) and younger patients (P < 0.0001)., Conclusions: The high variability of the number of cramps experienced suggests that clinical trials will need to use crossover designs or large numbers of participants, even when the treatment effect is substantial., (© 2015 Wiley Periodicals, Inc.)

Background: Common discomforts of pregnancy experienced in the lower extremity include sciatica, leg cramps and varicose veins. Whilst research attention has focused on aetiology and outcomes, the health service utilisation of pregnant women suffering from these complaints has been largely overlooked., Aim: To examine the health status and health service utilisation profile of pregnant women experiencing sciatica, leg cramps or varicose veins., Methods: Linear and logistic regression was applied to a cross-sectional survey of a pregnant women drawn from the 1973 to 1978 cohort (aged 31-36 years in 2009), of the Australian Longitudinal Study on Women's Health (n=1835). Participant's demographics, health status and health service utilisation were compared for all three complaints based upon three subgroups (yes, sought help; yes, did not seek help; no)., Findings: A number of women experienced sciatica (22.1%), leg cramps (18.2%) or varicose veins (9.4%). Of these, a greater proportion of women with sciatica (79.3%) or varicose veins (71.5%) sought help for their condition compared with women with leg cramps (46.7%). Comparisons between women with the conditions of interest who did seek help and those who did not only found that women with a university degree were 0.29 (95% CI: 0.10, 0.85) times less likely to seek help for their condition compared to women with a school only education., Conclusion: Further research examining all health seeking behaviour and treatment use of pregnant women who experience lower extremity problems is required in order to facilitate safe, effective and coordinated maternity care to further support these women during pregnancy., (Copyright © 2015 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.)

Positive muscle phenomena are due to muscle overactivity. Examples are cramp, myalgia, and stiffness. These manifestations have mostly acquired causes, e.g. side-effects of medication, metabolic disorders, vitamin deficiency, excessive caffeine intake or neurogenic disorders. We report on three patients with various positive muscle phenomena, to illustrate the clinical signs that indicate an underlying myopathy. Patient A, a 56-year-old man, was diagnosed with muscle cramp in the context of excessive coffee use and previous lumbosacral radiculopathy. Patient B, a 71-year-old man, was shown to have RYR1-related myopathy. Patient C, a 42-year-old man, suffered from Brody myopathy. We propose for clinicians to look out for a number of 'red flags' that can point to an underlying myopathy, and call for referral to neurology if indicated. Red flags include second wind phenomenon, familial occurrence of similar complaints, marked muscle stiffness, myotonia, muscle weakness, muscle hypertrophy, and myoglobinuria. Establishing a correct diagnosis is important for proper treatment. Certain myopathies call for cardiac or respiratory screening.

Monitoring of dialysis sessions is crucial as different stress factors can yield suffering or critical situations. Specialized personnel is usually required for the administration of this medical treatment; nevertheless, subjects whose clinical status can be considered stable require different monitoring strategies when compared with subjects with critical clinical conditions. In this case domiciliary treatment or monitoring can substantially improve the quality of life of patients undergoing dialysis. In this work, we present a Computer Aided Detection (CAD) system for the telemonitoring of patients' clinical parameters. The CAD was mainly designed to predict the insurgence of critical events; it consisted of two Random Forest (RF) classifiers: the first one (RF1) predicting the onset of any malaise one hour after the treatment start and the second one (RF2) again two hours later. The developed system shows an accurate classification performance in terms of both sensitivity and specificity. The specificity in the identification of nonsymptomatic sessions and the sensitivity in the identification of symptomatic sessions for RF2 are equal to 86.60% and 71.40%, respectively, thus suggesting the CAD as an effective tool to support expert nephrologists in telemonitoring the patients.

Various medications and behavioral treatments for sleep-related leg cramps have been tried, but the quality of the evidence is low. Quinine seems to be effective, but dangerous. β-Agonists may be one of the more common causes of secondary leg cramps. Statins may not be implicated in leg cramps as much as has been believed. Potassium-sparing diuretics may have a higher incidence of sleep-related leg cramps than potassium-depleting diuretics. Plantar flexion of the feet may elicit most sleep-related leg cramps. More research into behavioral treatments is needed. A standardized sleep-related leg cramp questionnaire would be useful to expand research., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Becker muscular dystrophy (BMD) was first described in 1953 by Emile Becker as a benign variant of Duchenne muscular Dystrophy (DMD). Compared with DMD, BMD is clinically more heterogeneous, with initial presentation in the teenage years and loss of ambulation beyond the age of 16 and a wide spectrum of clinical presentations, ranging from only myalgias and muscle cramps to exercise intolerance and myoglobinuria, asymptomatic elevation of serum creatin-kinase, or mild limb-girdle weakness and quadriceps myopathy. About 50% of patients become symptomatic by the age of 10 and the most part by the age of 20 years. However few patients can be free of symptoms till their fifties and cases of late-onset Becker Muscular Dystrophy have also been described. In this report we describe the clinical features of patients with dystrophinopathy sharing a deletion of exons 45-55, occasionally or retrospectively diagnosed. These data are important for both the prognostic aspects of children presenting this dystrophin gene mutation, and for the genetic counseling in these families (reassuring them on the benign course of the disease), and last but not least to keep in mind a diagnosis of BMD in asymptomatic adults with mild hyperckemia.