The aetiology of growing pains remains uncertain, with three main theories held. The anatomical theory (Naish & Apley 1951) suggested that orthopaedic factors such as flat feet or knock knees create increased leg muscle work. The fatigue theory (Bennie 1894) alluded to an overuse response of the leg muscles in active children. The psychological or emotional theory (Oberklaid et al 1997) has viewed growing pains in a wider pain sphere including abdominal pains and headaches (Mikkelsson et al 1997a, 1998).

There have also been preliminary links between foot posture and growing pains (Evans 2003, Naish & Apley 1951) which have subsequently been well investigated and refuted (Evans & Scutter 2007). Suggested associations of functional health with growing pains (Atar et al 1992) revealed that children with growing pains were heavier than their unaffected peers (Evans et al 2006), which may have implications for childhood obesity.

Recent studies (Hashkes et al 2004, Friedland et al 2005, Noonan et al 2004) and a review (Uziel & Hashkes 2007) have identified issues such as lowered pain thresholds (Hashkes et al 2004) in children affected by growing pains, suggesting that growing pains is a more generalized pain syndrome. Bone strength has been reported to be decreased in children with growing pains (Friedland et al 2005), especially in the tibiae, which may suggest bone fatigue as a factor. Vascular changes have been cited, but as yet not implicated, in children with growing pains (Uziel & Hashkes 2007). However, a higher occurrence of growing pains has been found in children who also experience migraine headaches (Aromaa et al 2000, Oster 1972, Mikkelsson et al 1997b).

A family pattern and tendency towards growing pains has been demonstrated, with approximately 70% of children with growing pains having an affected parent or sibling (Evans et al 2006). While many studies have implicated family patterns and responses to pain as being a part of the growing pains picture (Apley 1976, Naish & Apley 1951, Oberklaid et al 1997), there has been only preliminary investigation of effects on children’s quality of life (Uziel & Hashkes 2007). There is concern that children whose pain is inadequately addressed and relieved may become adolescents and adults who cope less ably with pain, which has large social and health cost implications (Eccleston & Malleson 2003, Uziel & Hashkes 2007). It is therefore important that a frequent and prevalent childhood complaint such as growing pains be well identified and managed.

There are some 10 prevalence studies with estimates ranging from approximately 2% to 49% (Evans & Scutter 2004a, Williams 1928). However, many of these studies were methodologically problematic using inconsistent criteria for growing pains and investigating very different age groups and sample sizes of children. Recently the prevalence of growing pains was established as 36.9% (95% CI 32.7–41.1%) in a rigorous study of 1445 children aged 4–6 years (Evans & Scutter 2004a). This study utilized the specifically designed University of South Australia Growing Pains Questionnaire (USAGPQ), which is a useful instrument for both the clinician and the researcher (Evans, Scutter, 2004b and Evans, Scutter, 2004c; see Appendix 7.1).

The clinician must always keep in mind other possible, if infrequently occurring, causes of leg pain in children. Often children undergo extensive laboratory examinations to eliminate concerns of more sinister entities (Macarthur et al 1996). Juvenile arthritis should be considered if the pains are articular in nature or associated with any clinical findings such as joint swelling or morning stiffness. A bone tumour should be considered if the pain is focal and unilateral and not only occurring at night-time. Restless legs (sometimes termed Ekbom’s syndrome) may also be implicated or coexist (Ekbom 1975, Rajaram et al 2004). The diagnosis of growing pains is greatly assisted if the definition as depicted in Table 7.1 is adhered to. However, if the signs or symptoms are atypical the diagnosis of growing pains should not be made until other investigations rule out other possible causes. Table 7.2 outlines the differential diagnoses which should be considered if the criteria in Table 7.1 are not met. Referral to a paediatrician or to other medical personnel should be arranged if the diagnosis of growing pains does not fit, or changes from, the typical clinical picture.

Classically the child presents with the following story from their parents: their otherwise well child has been complaining of sore, aching legs at bed-time and/or waking up in the middle of the night complaining of the same thing. The level of reported distress will vary from complaining to screaming, with crying being a fair delineator in terms of the intensity of pain. Milder presentations report the child complaining and whining and often able to be alleviated with parental reassurance, a parent rubbing the child’s legs, use of a hot water bottle (or equivalent) and perhaps paracetamol. Medication is usually given when the child is very distressed and some parents report that this is the only way to settle their child, while others find non-medication measures adequate. The typical pattern of growing pain episodes is that these occur in spates, e.g. a few nights over a week and then none for perhaps a month. Most affected children experience pains between 1 and 3 monthly intervals. Some parents notice a pattern of episodes on the nights that their child has been particularly active physically and begin to predict these events. There is usually a family history of growing pains and most parents do not consult a health professional. It is probable that it is in more severe, unrelenting cases or cases without a family history that a professional is consulted.

Unfortunately, some parents who consult a health professional can be/feel somewhat dismissed and not taken seriously. This is a pity, as growing pains is a common childhood complaint which needs to be recognized, appreciated and managed effectively as outlined below. The ill-founded view that ‘there’s no such thing as growing pains’ needs to be dispensed with as it is both ignorant and unhelpful to parents and affected children.

There is a veritable plethora of cited ways to treat children with growing pains. Everything from heat packs, stretching, massage, paracetamol, vitamin C, magnesium and zinc supplements, stabilizing leather pelvic belts, foot orthoses and probably other options have been expounded and recommended.