Somatosensory test responses in children with growing pains

Improved definition of growing pains: A common familial primary pain disorder of early childhood

Background

Commonly applied diagnostic criteria for growing pains (GP) have evolved without determination by an authoritative representative body. GP and restless legs syndrome (RLS) share anatomical, distributional, temporal, and other clinical features and are associated in individuals over time, in families, and in population samples. In this study, we tested the hypothesis that GP, diagnosed by widely used criteria, is confounded by cases of painful restless legs syndrome (RLS-Painful).

Methods

A twin family study of genetic influence and associations of GP using questionnaires was administered by Twins Research Australia. Twins (3-18 years; monozygous 503, dizygous 513), their oldest siblings, mothers, and fathers were randomly selected from the twin registry. Family members completed the questionnaires assessing lifetime prevalence of GP by commonly applied criteria and covariates including the history of iron deficiency and pediatric pain disorders. A GP-Specific phenotype was defined as GP without urge to move the legs. We determined similarities in twin pairs for the GP and GP-Specific phenotypes, family associations, and estimated familial and individual-specific associations for each phenotype.

Results

Lifetime prevalence was one-third lower for GP-Specific than for GP among the twin and family members. Monozygous twin pairs were more similar than dizygous twin pairs for GP and for the derived GP-Specific phenotype by three methods, consistent with genetic influence. There were familial associations, but the essential evidence for genetic influence was the twin-cotwin data. GP was associated, in multivariable analyses, with migraine, headaches, recurrent abdominal pain, and iron deficiency, while GP-Specific associations were limited to migraine and headaches.

Conclusions

GP is hybrid, one-third of cases having symptoms and associations of RLS, necessarily RLS-Painful. GP-Specific (without symptoms and associations of RLS) could have a genetic etiology. We propose new criteria to facilitate etiological and therapeutic research.

Somatosensory Testing in Pediatric Patients with Chronic Pain: An Exploration of Clinical Utility

We aimed to evaluate the utility of clinical somatosensory testing (SST), an office adaptation of laboratory quantitative sensory testing, in a biopsychosocial assessment of a pediatric chronic somatic pain sample (N = 98, 65 females, 7–18 years). Stimulus–response tests were applied at pain regions and intra-subject control sites to cutaneous stimuli (simple and dynamic touch, punctate pressure and cool) and deep pressure stimuli (using a handheld pressure algometer, and, in a subset, manually inflated cuff). Validated psychological, pain-related and functional measures were administered. Cutaneous allodynia, usually regional, was elicited by at least one stimulus in 81% of cases, most frequently by punctate pressure. Central sensitization, using a composite measure of deep pressure pain threshold and temporal summation of pain, was implied in the majority (59.2%) and associated with worse sleep impairment and psychological functioning. In regression analyses, depressive symptoms were the only significant predictor of pain intensity. Functional interference was statistically predicted by deep pressure pain threshold and depressive symptoms. Manually inflated cuff algometry had comparable sensitivity to handheld pressure algometry for deep pressure pain threshold but not temporal summation of pain. SST complemented standard biopsychosocial assessment of pediatric chronic pain; use of SST may facilitate the understanding of disordered neurobiology.

[Growing Pains : Cause, Significance and Treatment]

BACKGROUND

Leg pain is a common reason for consultation in the children's orthopedic clinic. It can occur across all age groups, although most patients are of pre-school or elementary school age. As there are a series of possibly severe differential diagnoses that might cause such pains in children and adolescents apart from benign pains that occur in the context of growth, a thorough patient history and physical examination are essential.

PATHOGENESIS

Despite extensive research, the cause of benign growing pains has not been elucidated so far. Several possible factors play a role on an anatomical, metabolic or functional basis, ; thus, various theories exist with regard to their origin.

DIAGNOSIS

Growing pains constitute a diagnosis of exclusion. If a possible organic cause of the pains is suspected, an extended diagnosis of the person affected should be made. Growing pains primarily occur at night and are always self-resolving.

THERAPY

With regard to treatment, mild pain medications can be employed in more severely affected patients. It is much more important to inform family members about the benign nature of the condition. Reassuring words and physical relaxation exercises, in addition to massaging and stretching of the leg muscles, can cause a significant reduction in pain without medication.

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.