Significant association among growing pains, vitamin D supplementation, and bone mineral status: results from a pilot cohort study

Growing pains in Danish preschool children: a descriptive study

This study provides a detailed description of growing pains in young Danish children as standardized diagnostic criteria are needed to avoid misclassifications of other musculoskeletal diagnoses. The study is nested in a cohort study of Danish preschool children. At baseline, parents completed a questionnaire with sociodemographic information. During the study, the parents received a text message every two weeks inquiring about musculoskeletal pain in the child. If pain was reported, a telephone interview about pain characteristics was conducted. The present study includes data from 2016 to 2019 with 777 children, aged 3-6 years of age at baseline. The prevalence of growing pains was 24-43%, depending on the definition. The pain occurred most frequently 1-3 times per week and most commonly in the lower legs, could be unilateral or bilateral and was usually without consequences. The prevalence increased with age, and there were no consistent associations with socio-economic factors. We suggest using Evan's criteria with the addition of unilateral pain as standard diagnostic criteria in the future. We found no relation to periods of rapid growth and suggest that the term is a misnomer. Etiology and long-term courses of pain need to be explored in future studies.

Clinical, laboratory characteristics and growth outcomes of children with growing pains

Growing pains (GP), a common and benign pain syndrome of unknown etiology, is characterized by bilateral recurrent leg pain in childhood. There are no standardized diagnostic criteria for GP, and the diagnosis is often made by exclusion. To identify clinical and laboratory features, we included patients < 12 years with GP at National Taiwan University Children's Hospital between April 2006 and April 2019 in a retrospective study. We also compared body weight and body height z-scores between diagnosis and up to 2 years post-diagnosis to determine if rapid growth was associated with GP. This cohort study included 268 patients with a mean age of 4.7 ± 2.2 years. The most common features of GP were bilateral leg pain, no limitation of activity, intermittent pain, normal physical examination, and being well physically. The average number of Walters' criteria fulfilled by the patients with GP was 6.7 ± 0.9. Elevated serum levels of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) were observed in 37.5% and 15.6% of patients, respectively. Symptomatic medications were used in 33% of patients. Our study indicates that ALP and LDH may be biomarkers associated with GP. There was no significant association between GP and rapid growth within 2 years of diagnosis.

Defining Growing Pains: A Scoping Review

BACKGROUND AND OBJECTIVES

Up to one third of children may be diagnosed with growing pains, but considerable uncertainty surrounds how to make this diagnosis. The objective of this study was to detail the definitions of growing pains in the medical literature.

METHODS

Scoping review with 8 electronic databases and 6 diagnostic classification systems searched from their inception to January 2021. The study selection included peer-reviewed articles or theses referring to "growing pain(s)" or "growth pain(s)" in relation to children or adolescents. Data extraction was performed independently by 2 reviewers.

RESULTS

We included 145 studies and 2 diagnostic systems (ICD-10 and SNOMED). Definition characteristics were grouped into 8 categories: pain location, age of onset, pain pattern, pain trajectory, pain types and risk factors, relationship to activity, severity and functional impact, and physical examination and investigations. There was extremely poor consensus between studies as to the basis for a diagnosis of growing pains. The most consistent component was lower limb pain, which was mentioned in 50% of sources. Pain in the evening or night (48%), episodic or recurrent course (42%), normal physical assessment (35%), and bilateral pain (31%) were the only other components to be mentioned in more than 30% of articles. Notably, more than 80% of studies made no reference to age of onset in their definition, and 93% did not refer to growth. Limitations of this study are that the included studies were not specifically designed to define growing pains.

CONCLUSIONS

There is no clarity in the medical research literature regarding what defines growing pain. Clinicians should be wary of relying on the diagnosis to direct treatment decisions.

Application of bone metabolic parameters in the diagnosis of growing pains

Objective

The present study aimed to assess the diagnostic significance of serum bone metabolic parameters in children with growing pains (GPs).

Methods

All patients diagnosed with GP and healthy controls matched with age and gender were recruited at the outpatient clinic of Children's Hospital at Zhejiang University School of Medicine from August 2016 to August 2021. In all subjects, serum levels of calcium (Ca), phosphorus (P), procollagen type‐I N‐terminal (PINP), parathormone (PTH), 25‐hydroxyvitamin D (25‐(OH)D), osteocalcin (OC), N‐terminal cross‐linked telopeptides of type‐I collagen (CTX), and tartrate‐resistant acid phosphatase type 5b (TRACP5b) were investigated. The univariate analysis, multivariate logistic regression analysis, and receiver operating characteristic (ROC) curve were used to identify the bone metabolic parameters factors for diagnosing GP.

Results

We enrolled 386 children with GP and 399 healthy controls in present study. The mean age of GP group was 5.319 years, and, primarily, the subjects were preschool‐age children. The gender ratio (male‐to‐female) was 1.27 in GP group. After adjusting for age and gender, we identified that the serum levels of Ca (p < 0.001, OR: 25.039), P (p = 0.018, OR: 2.681), PINP (p < 0.001, OR: 1.002), and PTH (p = 0.036, OR: 0.988) were independent diagnostic factors associated with GP. Area under curve (AUC) of the ROC curves was in the order: PINP (0.612) > Ca (0.599) > P (0.583) > PTH (0.541). A combination of independent diagnostic factors and multivariable logistic regression analysis provided a refined logistic regression model to improve the diagnostic potential, of which the AUC had reached 0.655.

Conclusions

Serum levels of Ca, P, PINP, and PTH could be independent diagnostic factors associated with GP. The logistic model was significantly superior to bone metabolic parameters for diagnosing GP.

The effects of vitamin D supplementation in carpal tunnel syndrome treatment outcomes: a systematic review

PURPOSE

Vitamin D deficiency is related to carpal tunnel syndrome symptoms. Correcting vitamin D levels by supplementation was supposed to improve carpel tunnel symptoms, though there is a lack of aggregated data about treatment outcomes. This study aimed to examine whether vitamin D supplementation could improve the treatment outcomes in carpal tunnel syndrome patients.

METHODS

A comprehensive search of the PubMed, Cochrane Library, Scopus, and Web of Science databases for articles on vitamin D and carpel tunnel syndrome from January 2000 to March 2021 was performed. The article screening and data extraction were performed by two investigators independently with blinding to decisions on selected studies. All included studies had assessed the quality of evidence using the Methodological Index for Non-Randomized Studies (MINORS) scoring system.

RESULTS

We retrieved four studies that met the eligibility criteria. The treatment outcomes were evaluated by visual analog scale (124 wrists), functional scores (176 patients), muscle strength (84 patients), and nerve conduction velocity (216 wrists). After vitamin D supplementation, two studies reported improved pain scores and nerve conduction velocity, and three studies showed enhancement of functional status.

CONCLUSION

Vitamin D administration could offer favorable outcomes in pain improvement, better functional status, and increased sensory conduction velocity in carpal tunnel syndrome. However, there is to date no recommendations concerning a standardized dose or duration of vitamin D administration in carpal tunnel syndrome; prescribing vitamin D at the usual appropriate dose is suggested as an additional treatment in patients with mild to moderate carpel tunnel symptoms.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Vitamin D and Its Potential Interplay With Pain Signaling Pathways

About 50 million of the U.S. adult population suffer from chronic pain. It is a complex disease in its own right for which currently available analgesics have been deemed woefully inadequate since ~20% of the sufferers derive no benefit. Vitamin D, known for its role in calcium homeostasis and bone metabolism, is thought to be of clinical benefit in treating chronic pain without the side-effects of currently available analgesics. A strong correlation between hypovitaminosis D and incidence of bone pain is known. However, the potential underlying mechanisms by which vitamin D might exert its analgesic effects are poorly understood. In this review, we discuss pathways involved in pain sensing and processing primarily at the level of dorsal root ganglion (DRG) neurons and the potential interplay between vitamin D, its receptor (VDR) and known specific pain signaling pathways including nerve growth factor (NGF), glial-derived neurotrophic factor (GDNF), epidermal growth factor receptor (EGFR), and opioid receptors. We also discuss how vitamin D/VDR might influence immune cells and pain sensitization as well as review the increasingly important topic of vitamin D toxicity. Further in vitro and in vivo experimental studies will be required to study these potential interactions specifically in pain models. Such studies could highlight the potential usefulness of vitamin D either alone or in combination with existing analgesics to better treat chronic pain.

Growing pains: What do we know about etiology? A systematic review

BACKGROUND

Growing pains is the most common cause of musculoskeletal pain in early childhood and was first described in 1823 by French physician Marcel Duchamp. Although it has been researched extensively, the etiology is still unknown. Several theories have been proposed throughout the years.

AIM

Analyze the available scientific literature to provide an update on the latest evidence on the etiology.

METHODS

According to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, the scientific literature on the etiology of growing pains was systematically reviewed using the following inclusion criteria: studies of any level of evidence reporting clinical or preclinical results and dealing with the etiology of growing pains. The medical electronic databases PubMed and Web of Science were searched by two independent authors on October 20, 2018. The search string used was “(growing pains OR benign nocturnal limb pains OR musculoskeletal pains) AND (etiology OR pathogenesis) AND (pediatrics)”.

RESULTS

A total of 32 articles were included. The etiology of growing pains still remains poorly understood. Many theories have been proposed, but none of them are decisive. A lower pain threshold has been found among patients suffering from growing pains in comparison to healthy controls. Furthermore, evidence suggests an association between growing pains and reduced bone strength in young patients, although this finding still remains controversial. Changes in the vascular perfusion pattern have also been studied. However, the etiology of growing pains does not seem related to a vascular component. The anatomical/mechanical theory has not been supported, but the role of vitamin D deficiency has been investigated many times. Strong recent evidence indicates a genetic susceptibility in the pathogenesis of growing pains. Furthermore, psychological factors also seem to play a strong role in the onset.

CONCLUSION

The scientific literature about the etiology of growing pains presents heterogeneity and lack of consensus; more studies are needed to understand the genesis of benign musculoskeletal pain syndrome of childhood.

A pilot validation study of crowdsourcing systematic reviews: update of a searchable database of pediatric clinical trials of high-dose vitamin D

BACKGROUND

Completing large systematic reviews and maintaining them up to date poses significant challenges. This is mainly due to the toll required of a small group of experts to screen and extract potentially eligible citations. Automated approaches have failed so far in providing an accessible and adaptable tool to the research community. Over the past decade, crowdsourcing has become attractive in the scientific field, and implementing it in citation screening could save the investigative team significant work and decrease the time to publication.

METHODS

Citations from the 2015 update of a pediatrics vitamin D systematic review were uploaded to an online platform designed for crowdsourcing the screening process (http://www.CHEORI.org/en/CrowdScreenOverview). Three sets of exclusion criteria were used for screening, with a review of abstracts at level one, and full-text eligibility determined through two screening stages. Two trained reviewers, who participated in the initial systematic review, established citation eligibility. In parallel, each citation received four independent assessments from an untrained crowd with a medical background. Citations were retained or excluded if they received three congruent assessments. Otherwise, they were reviewed by the principal investigator. Measured outcomes included sensitivity of the crowd to retain eligible studies, and potential work saved defined as citations sorted by the crowd (excluded or retained) without involvement of the principal investigator.

RESULTS

A total of 148 citations for screening were identified, of which 20 met eligibility criteria (true positives). The four reviewers from the crowd agreed completely on 63% (95% CI: 57-69%) of assessments, and achieved a sensitivity of 100% (95% CI: 88-100%) and a specificity of 99% (95% CI: 96-100%). Potential work saved to the research team was 84% (95% CI: 77-89%) at the abstract screening stage, and 73% (95% CI: 67-79%) through all three levels. In addition, different thresholds for citation retention and exclusion were assessed. With an algorithm favoring sensitivity (citation excluded only if all four reviewers agree), sensitivity was maintained at 100%, with a decrease of potential work saved to 66% (95% CI: 59-71%). In contrast, increasing the threshold required for retention (exclude all citations not obtaining 3/4 retain assessments) decreased sensitivity to 85% (95% CI: 65-96%), while improving potential workload saved to 92% (95% CI: 88-95%).

CONCLUSIONS

This study demonstrates the accuracy of crowdsourcing for systematic review citations screening, with retention of all eligible articles and a significant reduction in the work required from the investigative team. Together, these two findings suggest that crowdsourcing could represent a significant advancement in the area of systematic review. Future directions include further study to assess validity across medical fields and determination of the capacity of a non-medical crowd.

Perinatal Risk Factors and Genu Valgum Conducive to the Onset of Growing Pains in Early Childhood

The most prevalent musculoskeletal disorder of childhood with unclear aetiology is growing pains (GPs). Anatomic deformities and factors that change bone turnover are implicated in GP pathophysiology. Perinatal risk factors alter the bone metabolism affecting the bone mineral density and content. The aim of our study was to analyze the relationship between GPs, knock knees and perinatal factors. The examined population consisted of 276 children aged 3–7 years. Among them, ten pairs of dizygotic twins were evaluated. The data were collected by using a combination of semi-structured questionnaires, clinical examinations and medical charts of the children and the obstetric history of the mothers. A total of 78 children presenting GPs met Peterson’s criteria. Genu valgum severity was a significant factor for GP manifestation and for their increased frequency and intensity. Subsequently, perinatal factors regarding gestational age, Apgar score, head circumference (lower than 33 cm) and birth length or weight (smaller than 50 cm and 3000 g, respectively) made a remarkable contribution to the development of GPs. Conversely, antenatal corticosteroid treatment, increased maternal age and maternal smoking during pregnancy were not predictive of the disorder. Our data are potentially supportive for the “bone strength” theory and for the contribution of anatomical disturbances in GP appearance.

Are Growing Pains Related to Vitamin D Deficiency? Efficacy of Vitamin D Therapy for Resolution of Symptoms

OBJECTIVES

The aim of this study was to investigate the 25-hydroxyvitamin D [25(OH)D] status of children with growing pains and to evaluate the efficacy of vitamin D treatment on the resolution of pain symptoms.

SUBJECTS AND METHODS

One hundred and twenty children with growing pains were included in a prospective cohort study. Serum 25(OH)D and bone mineral levels were measured in all subjects at the time of enrollment. The pain intensity of those with vitamin D deficiency was measured using a pain visual analog scale (VAS). After a single oral dose of vitamin D, the pain intensity was remeasured by means of the VAS at 3 months. The 25(OH)D levels and VAS scores before and after oral vitamin D administration were compared by means of a paired Student's t test.

RESULTS

In the 120 children with growing pains, vitamin D insufficiency was noted in 104 (86.6%). Following vitamin D supplementation, the mean 25(OH)D levels increased from 13.4 ± 7.2 to 44.5 ± 16.4 ng/ml, the mean pain VAS score decreased from 6.8 ± 1.9 to 2.9 ± 2.5 cm (a mean reduction of -3.8 ± 2.1, p < 0.001) and the difference was statistically significant.

CONCLUSION

Supplementation with oral vitamin D resulted in a significant reduction in pain intensity among these children with growing pains who had hypovitaminosis D.