- Email: [email protected]
Growing pains in children: Epidemiological analysis in a Mediterranean population
Joint Bone Spine 76 (2009) 486–490
Original article
Growing pains in children: Epidemiological analysis in a Mediterranean population Angelos Kaspiris a,∗ , Chrisi Zafiropoulou b a
Department of Trauma and Orthopaedics, Thriasio General Hospital–NHS, G. Gennimata Avenue, Magoula 19600, Attica, Greece b Sector of Paediatrics, OAEE National Primary Care Trust, 21-23 Gounari Avenue, Patras 26221, Achaia, Greece Accepted 2 February 2009 Available online 29 September 2009
Abstract Objectives: Recurrent lower limb pains (growing pains) constitute the most frequent cause of musculoskeletal pain in children. Despite the fact that the international literature has presented numerous cases over the years, which have led to various hypotheses and theories, the disorder’s exact nature and aetiology remain unclear. Methods: Our study aims to examine both the epidemiological profile of the children affected by the disorder and the measures taken by parents or medical specialists for their management. In addition, we tried to link the existing theories with the findings of our study, to ascertain whether these were verified by the epidemiological findings. This retrospective study investigated the appearance of lower limbs in the 12-month period before the visit of the children to our department. The study included a total of 532 children, aged 4–12, while the data were collected through semi-structured interviews including a mix of open and closed questions. Results: One hundred and thirty of these children presented growing pains, meeting Petersen’s criteria. The frequency of the disorder was 24.5%. Most times, they appeared after intensive physical exercise, while their development was not linked to the children’s BMI. The main therapeutic approach used by parents was massaging the painful lower limbs and, to a lesser extent, the administration of anti-inflammatory agents. Conclusions: The data analysis proves that this is a benign disorder with an unknown pathophysiological mechanism. In addition, their presence is not strongly related to anatomic or orthopaedic disorders, a fact opposing anatomical theory. On the contrary, their appearance after intensive physical exercise at a percentage of up to 78.5% leads us to hypothesise that it is a lower local extremity overuse syndrome, which seems in accordance with many experimental data in international literature. © 2009 Société franc¸aise de rhumatologie. Published by Elsevier Masson SAS. All rights reserved. Keywords: Growing pains; Children; Epidemiology
1. Introduction Recurrent lower limb pains (growth pains) constitute the most frequent cause of musculoskeletal pain in children [1]. Despite the fact that they were first mentioned by the French doctor Duchamp in 1823 [2], limited progress has been made in understanding the disorder’s pathophysiological mechanism. Although many researchers have tried to set specific diagnostic criteria, the most useful clinical guidelines were created by Petersen [3,4] and completed by Russel and Abu-Arafeh [5]. These specific criteria determine growing pains based on the clinical picture the children present and as recurrent pains of
∗
Corresponding author. E-mail address: [email protected] (A. Kaspiris).
the lower limbs, with a duration of under 72 hours, not accompanied by bone localization or restrictions in the movement of one of more joints and no trauma, oedema, redness, localised sensitivity or other signs of local or generalised inflammation. Although the disorder is quite common, few studies have been published in international literature that examine the epidemiological profile of children presenting these specific pains, which could lead to some useful conclusions as to its aetiology. In a previous study, we examined the influence of breastfeeding on the risk and frequency of growing pains [6]. The aim of the present study is to improve the understanding of the epidemiological data of affected 4- to 12-year olds. In specific, we examine the relationship between growing pains, anthropometric characteristics and the activity levels of the affected children, as well as the diagnostic approach followed.
1297-319X/$ – see front matter © 2009 Société franc¸aise de rhumatologie. Published by Elsevier Masson SAS. All rights reserved. doi:10.1016/j.jbspin.2009.09.001
A. Kaspiris, C. Zafiropoulou / Joint Bone Spine 76 (2009) 486–490
2. Methods This is a retrospective study using questionnaires for the collection of data. It took place from 15 September 2006 to 15 January 2007, during the children’s visits to the paediatric departments of our organisation. By law, children of up to 14 years must be examined by paediatricians and not by GPs. This fact ensures the reliability of our results. Data were collected with the use of semi-structured interviews (a mix of open and closed questions) with parents and children of 4- to 12-year olds, at a frequency corresponding to their daily visits. These visits took place either for routine check-ups and vaccinations, or for the diagnosis and management of some other condition. The sample was representative based on geographical distribution, as it included children from local urban, rurban and rural areas, and social criteria, as arising from the participants’ social insurance. The questionnaire used included questions concerning the appearance of growing pains during the year before the children’s visit to our department, as well as the forms in which they were manifest, the determination of the children’s height, age and weight, frequency of visits to paediatricians or paediatric orthopaedics, the number to conducted examinations, their management as well as their relationship with the children’s activities, the co-existence of other orthopaedic problems or other events, such as a sudden increase in height. The children’s parents were fully briefed as regards the nature and aim of this study and courteously provided their consent thereupon. The whole study complies with the regulations of our organization and the Helsinki Declaration. The study sample includes 532 children, aged 4–12 years, from the area of Achaia, Greece’s third most populous region. Based on the data of the National Statistical Service, the size of the study’s sample, which corresponds to 1.71% of the studied population, allows for the reduction of results for the sum of children in our prefecture. Overall, it was deemed that 130 children presented growing pains, according to Petersen’s criteria. One child was excluded from the study, due to the localization of the pain at the hip and the impaired mobility of the hip, which did not comply with Petersen’s criteria. All data were entered in a Microsoft Excel 2003 file, and were analyzed with the SPSS 13.0 system. To extract conclusions on the results’ statistical significance, we used: Pearson’s Chi-Square Significance Test, with a significance level of 0.05 in combination with Fisher’s Exact Test – for 2 × 2 frequency charts – with a significance level of 0.05.
487
M/F ratio in the sample corresponds to the distribution of the two sexes in the population of this specific age group (4–12 years) in the Prefecture of Achaia, which means no data calculation based on the children’s sex is required. The same holds for the age group ratio. 3. Results The condition’s prevalence is relatively high, corresponding to 24.5% of children. The mean age of the participating children was 8.6 ± 2.5 years, while men height and weight were 132.7 ± 17.1 cm and 34.3 ± 12.8 kg respectively (BMI 1.5 ± 0.6). Although the children usually present these pains between the ages of 3–6, the above age-related finding can be explained by the nature of the study (retrospective), i.e. by the interval between the manifestation of the disease and the completion of the questionnaire. Another important result is that, based on the BMI, there is no statistically significant correlation between the children’s BMI and the appearance of growth pains. Underweight, normal and overweight children all have the same chance of presenting growth pains (Pearson’s Chi-Square p-value = 0.47 > 0.05) (Table 1). The demographic study reveals that the ratio of males to females presenting growing pains is 45:55 respectively. As seen in Table 1 however, there is no significant correlation between the child’s sex and the appearance of the condition (Fisher’s Exact test: p-value = 0.15 > 0.05). The vast majority (90.8%) of children affected by growing pains present these in both legs. 66.9% experience pain during the night while, in 16.2% of these, they lead to nocturnal awakening. A smaller percentage of 11.5% experience even more intense reactions, such as crying. Most incidents of pain (53.1%) appear to take place quite frequently or up to once a month, while they are experienced in their majority (78.5%) after intensive exercise. Their correlation with other events, such as a sudden increase in height or participation on specific sports is not strong. 6.2% of parents report the co-existence of orthopaedic problems, while just 4.2% of participants cannot correlate the pains with any specific aetiological factor (Table 2). A surprising finding is that, despite their increased frequency, only one in five parents visited a doctor for this reason. It is worth noting that neither the frequency nor the type of symptoms affects the frequency of visits to the doctor. For example, the parents of children presenting growing pains with increased
Table 1 Appearance of growing pains in children compared to their BMI. Present pains (n = 130) 24.5
Do not present pains (n = 401) 75.5
Total (n = 531) 100.00
Sex Boys Girls
(n = 61), 21.9 (n = 69), 27.3
(n = 217), 78.1 (n = 184), 72.7
(n = 278), 100.00 (n = 253), 100.00
BMI (kg/m2 ) Underweight Normal Overweight
(n = 63), 23.50 (n = 60), 26.70 (n = 7), 18.4
(n = 205), 76.50 (n = 165), 73.70 (n = 31), 81.6
(n = 268), 100.00 (n = 225), 100.00 (n = 38), 100.00
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A. Kaspiris, C. Zafiropoulou / Joint Bone Spine 76 (2009) 486–490
Table 2 Clinical profile of children presenting growing pains (n = 130). Types of pain presented by the children Nocturnal lower limb pains Nocturnal awakening Crying Pains in other parts of the body
(n = 87), 66.9 (n = 21), 16.2 (n = 15), 11.5 (n = 7), 5.3
Pain frequency Weekly Monthly Quarterly Half-yearly
(n = 36), 28.1 (n = 33), 25.0 (n = 21), 16.4 (n = 40), 30.5
Relationship with physical activities After intensive activity After participation in sports After sudden height increase Linked to orthopaedic problems of the lower limbs (platypodia, valgus knee, uneven limbs) No other cause Frequency of visits to doctor At least once a week Once a month Every trimester Every semester Therapeutic approach Massaging Anti-inflammatory–analgesic agents (paracetamol, acetaminophen, mefenamic acid) Warm compresses Rest Other (reported: ice or plaster applied, etc.)
(n = 102), 78.5 (n = 17), 13.1 (n = 19), 14.6 (n = 8), 6.2 (n = 6), 4.6 (n = 32), 25 (n = 32), 25 (n = 24), 17.9 (n = 42), 32.1 (n = 100), 77.5 (n = 23), 17.5 (n = 18), 13.8 (n = 13), 10.00 (n = 5), 3.80
frequency or with most severe symptomatology, such as nocturnal awakening or crying, do not consult paediatricians more often compared to the parents of children with milder lower limb pains (Pearson Chi-Square test p-value = 0.97 > 0.05). Regarding the specialisations of the doctors the parents consult, the study reveals that 15.3% of parents visit doctors of two different paediatric specialisations. 57.6% consult paediatricians, while a similar percentage visits orthopaedics. Small percentages visit other specialisations, such as rheumatologists or children’s endocrinologists. Finally, just 8.5% of children underwent lab tests (Table 2). The management of growing pains by parents differs, although the most popular treatment appears to be massaging the lower limbs. In some cases, this is done using a local anti-inflammatory cream and/or alcohol. These are followed in popularity by analgesics, warm compresses and rest with a reduction of physical activity (Table 2). 4. Discussion The condition’s prevalence varies and ranges from 2.6 [5] to 49.4% [7]. In a recent study, its prevalence on children in the 4–6 age group was 38.3% [8,9]. In our study, it was 24.5%, in accordance with most writers who report that prevalence is 20% at ages 4–14. Despite attracting the interest of many researchers, the condition’s aetiopathogenicity remains unclear. Four main theories
have been supported. The first is that of rapid skeletal development. The second is the theory of muscular and bone fatigue in highly active children. The third supports that the catalytic factors behind the condition’s appearance include anatomic and orthopaedic problems. Finally, it is believed that these pains may constitute the clinical manifestation of a more generalised pain syndrome that is linked to headaches and abdominal pain, possibly due to psychological stress suffered by the children. In 1823, Duchamp was the first to note that a large number of adolescent children presented an increased frequency of musculoskeletal pains and coined the term “growing pains” to describe them, believed that they were caused by rapid skeletal development [2]. Experimental data presented by Noonan et al. with the implantation of microtransducers at the conjunctive cartilage of the leg of three sheep showed that 90% of bone elongation takes place during lying, a fact consistent with the hypothesis of nocturnal bone elongation and directly linked with growing pains [10]. Epidemiological studies have not confirmed the above finding, as in the study by Evans et al., 35.9% of parents linked growing pains with sudden increases in height [8], while in our study, the corresponding percentage was just 14.6% (Table 2). Subsequently, Bennie adopted the above belief, adding that the catalytic factors for their appearance include intensive physical exercise during the day [11]. This fact was examined by Seham and Hilbert who found an additional relationship between the presence of the pains and insufficient sleep [12]. Indeed, only 15% of children who slept for sufficient hours presented pains, as compared to 34% of children who had not. Intensive physical exercise is linked to their appearance both in the study by Evans et al. at a percentage of 37.8% [8] and in our study, at a much higher percentage of 78.5% in fact (Table 2). Other writers reach similar conclusions for the 4–12 age group, with a percentage of 76%. Analysing a group of 115 children with growing pains, Hawksley reported that they are not linked to rheumatoid fever and concluded that their presence is more frequent in patients with mild orthopaedic conditions, such as platypodia, valgus knee or scoliosis [13]. He also suggested that the term “growing pains” does not accurately describe reality. Other studies however gave only very low percentages to co-existing orthopaedic problems, which amounted to 1.7 or 6.2% in the present study. In the Neish and Apley line in fact, only one out of 168 children presented an orthopaedic disorder (Osgood-Schlatter disease). On the contrary, body weight was significantly higher in children presenting pains, a fact that would support the anatomic theory. This however is not confirmed by our study by using the BMI (Table 1). In addition, neither the clinical measurement of foot posture between children presenting and not presenting growing pains found any significant difference, which also opposes the anatomic theory [14]. Abu-Arafeh hypothesised the existence of a common mechanism with child migraines, as they appeared in children who suffered, or whose parents suffered [15], from migrainetype headaches [5]. In parallel, they had a similar therapeutic approached as they alleviated with the use of analgesics, while 20% improved after sleep. In our research, rest (10%) and the use
A. Kaspiris, C. Zafiropoulou / Joint Bone Spine 76 (2009) 486–490
of analgesics (17.5%) also constitute a noteworthy way of managing the condition. This led to the theory that the affected legs present vascular disorders similar to those of migraine. Experimental findings with the use of Tc-99m bone scintiscans and ␥-cameras did not reveal any significant differences in vascular distribution in legs between the two above children’s groups [16]. Their frequent co-existence with other painful conditions, such as abdominal pain, leads to the conclusion that they may be caused by psychological stress. Although the children suffering from the condition have been reported to have high percentages of psychological problems that may reach 62% [17,18], we believe that further investigation in the field of psychosocial theories is required. Recent researches using dolorimeters showed that the pain threshold at the anterior tibia in children with growing pains is lower as compared to others, which relates to the fact that bone density in the painful areas in these children is much lower [19–21]. This finding supports the belief that we are facing a non-inflammatory pain syndrome, but for lower local extremity overuse syndrome with bony fatigue in children with a low pain threshold. These findings may be linked to the protective role played by breastfeeding in the avoidance of growing pains. In specific, a breastfeeding for over 40 days limits the risk of their appearance and modifies their clinical picture [6]. A surprising finding is that, despite their increased frequency, only one in five parents visited a doctor for this reason, irrespectively of the children’s clinical picture (Table 2). The question that arises of course is whether further paraclinical tests are in fact required for diagnosis and treatment. It seems that laboratory tests do not present significant differences between this group and the general population, with the possible exception of white blood cells (WBC) and mean corpuscular volume (MCV) counts, although mean WBC counts were in the normal range in both groups (as were haemoglobin concentrations) and no leucocytosis or leukopenia was noted in the affected children [22]. Judging from the above, we should underline that both lab and X-ray tests are of lesser importance, as a comprehensive history, with interviews with the children and their parents, and a detailed physical examination with a correct implementation of Petersen’s clinical criteria can on their own ensure a satisfactory diagnosis. The differential diagnosis of childhood lower limb pains includes numerous conditions, such as infectious diseases (cellulitis, osteomyelitis, Lyme disease), tumorous diseases (leukaemia, Ewing sarcoma, osteoid osteoma, neuroblastoma), non-inflammatory pain syndromes (fibromyalgia, restless legs syndrome), traumatic aetiology (fractures, joint strain, myositis ossificans), or even rheumatoid conditions (rheumatic fever, juvenile idiopathic arthritis, reactive arthritis) and vascular aetiology (sickle cell crisis, or haemophilia with hemarthrosis) [23]. Similarly, attention must be paid to cases of auto-inflammatory syndromes, which are rare genetic diseases noted by recurrent attacks of inflammation. These syndromes, such as Familial Mediterranean Fever (FMF) – which is common in the Greek population [24] –, Tumour Necrosis Factor (TNF), Receptor
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Periodic Syndrome (TRAPS) and Hyperimmunoglobulinaemia D syndrome (HIDS), which have joint manifestations in about 50% of cases in ages under 10 years [24]. Hence, any other finding, like fever, malaise, weight loss or decreased joint mobility, joint oedema, non-symmetric limb pains, or pains and joint rigidity in the morning, must trigger further lab and X-ray tests. Thus, the diagnosis of growing pains during the appearance of the above clinical signs, which are not included in Petersen’s Criteria (“atypical growing pains”), must only be made after a thorough lab and X-ray investigation and the exclusion of the above diseases. Conflicts of interest None of the authors has any conflicts of interest to declare. References [1] Al Khattat A, Campell J. Recurrent limb pain in childhood (“Growing pains”). Foot 2000;10:117–23. [2] Duchamp M. Maladies de la croissance. In: Levrault FG, editor. Mémoires de médecine practique. Paris: Jean-Frédéric Lobstein; 1823. [3] Petersen H. Leg aches. Pediatr Clin North Am 1977;24:731–6. [4] Petersen H. Growing pains. Pediatr Clin North Am 1986;33: 1365–72. [5] Abu-Arafeh IRG. Recurrent limb pain in school children. Arch Dis Child 1996;74:336–9. [6] Kaspiris A, Zafiropoulou C, Tsadira O, et al. Can breastfeeding avert the appearance of growth pains during childhood? Clin Rheumatol 2007;26:1909–12. [7] Williams MF. Rheumatic conditions in school children. Lancet 1928;211(5458):720–1. [8] Evans AM, Scutter SD, Lang LG, et al. “Growing pains” in young children: a study of the profile, experiences and quality of life issues of four- to six-year-old children with recurrent leg pain. Foot 2006;16:120–4. [9] Evans AM, Scutter SD. Prevalence of “Growing Pains” in young children. J Pediatr 2004;145:255–8. [10] Noonan KJ, Farnum CE, Leiferman EM, et al. Growing pains: are due to increased growth during recumbency as documented in a lamb model? J Pediatr Orthop 2004;24:726–31. [11] Bennie PB. Growing pains. Arch Pediatr 1894;11:337–47. [12] Seham M, Hilbert EH. Muscular rheumatism in childhood. Am J Dis Child 1933;46:826–33. [13] Hawksley JC. The nature of growing pains and their relation to rheumatism in children and adolescents. BMJ 1938;1:155–7. [14] Evans AM, Scutter SD. Are foot posture and fuctional health different in children with growing pains? Pediatr Int 2007;49:991–6. [15] Aroma M, Sillanpaa M, Rautava P, et al. Pain experience of children with headache and their families: a control study. Pediatrics 2000;106: 270–5. [16] Hashles PJ, Gorenberg M, Oren V, et al. “Growing pains” in children are not associated with changes in vascular perfusions patterns in painful regions. Clin Rheumatol 2005;24:342–5. [17] Mikkelson M, Salminen JJ, Kautiainen H. Non-specific musculoskeletal pain in preadolescents. Prevalence and 1-year persistance. Pain 1997;73:29–35. [18] Sherry DD, McGuire T, Mellinns E, et al. Psychosomatic musculoskeletal pain in childhood: clinical and psychological analysis of 100 children. Pediatrics 1991;88:1093–9. [19] Hashkes PJ, Friedland O, Jaber L, et al. Decreased pain threshold in children with growing pains. J Rheumatol 2004;31:610–3. [20] Friedland O, Hashkes PJ, Jaber L, et al. Decreased bone speed of sound in children with growing pains measured by quantitative ultrasound. J Rheumatol 2005;32:1354–7.
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[21] Uziel Y, Hashkes PJ. Growing pains in children. Pediatr Rheumatol 2007;19:5. [22] Asadi-Pooya AA, Bordbar MR. Are laboratory tests necessary in making the diagnosis of limb pains typical for growth pains in children? Pediatr Int 2007;49:833–5.
[23] Lowe RM, Hashked PJ. Growing pains: a non-inflammatory pain syndrome of early childhood. Nat Clin Pract Rheumatol 2008;4: 542–9. [24] Stankovic K, Grateau G. Auto-inflammatory syndromes: diagnosis and treatment. Joint Bone Spine 2007;74:544–50.
Original article
Growing pains in children: Epidemiological analysis in a Mediterranean population Angelos Kaspiris a,∗ , Chrisi Zafiropoulou b a
Department of Trauma and Orthopaedics, Thriasio General Hospital–NHS, G. Gennimata Avenue, Magoula 19600, Attica, Greece b Sector of Paediatrics, OAEE National Primary Care Trust, 21-23 Gounari Avenue, Patras 26221, Achaia, Greece Accepted 2 February 2009 Available online 29 September 2009
Abstract Objectives: Recurrent lower limb pains (growing pains) constitute the most frequent cause of musculoskeletal pain in children. Despite the fact that the international literature has presented numerous cases over the years, which have led to various hypotheses and theories, the disorder’s exact nature and aetiology remain unclear. Methods: Our study aims to examine both the epidemiological profile of the children affected by the disorder and the measures taken by parents or medical specialists for their management. In addition, we tried to link the existing theories with the findings of our study, to ascertain whether these were verified by the epidemiological findings. This retrospective study investigated the appearance of lower limbs in the 12-month period before the visit of the children to our department. The study included a total of 532 children, aged 4–12, while the data were collected through semi-structured interviews including a mix of open and closed questions. Results: One hundred and thirty of these children presented growing pains, meeting Petersen’s criteria. The frequency of the disorder was 24.5%. Most times, they appeared after intensive physical exercise, while their development was not linked to the children’s BMI. The main therapeutic approach used by parents was massaging the painful lower limbs and, to a lesser extent, the administration of anti-inflammatory agents. Conclusions: The data analysis proves that this is a benign disorder with an unknown pathophysiological mechanism. In addition, their presence is not strongly related to anatomic or orthopaedic disorders, a fact opposing anatomical theory. On the contrary, their appearance after intensive physical exercise at a percentage of up to 78.5% leads us to hypothesise that it is a lower local extremity overuse syndrome, which seems in accordance with many experimental data in international literature. © 2009 Société franc¸aise de rhumatologie. Published by Elsevier Masson SAS. All rights reserved. Keywords: Growing pains; Children; Epidemiology
1. Introduction Recurrent lower limb pains (growth pains) constitute the most frequent cause of musculoskeletal pain in children [1]. Despite the fact that they were first mentioned by the French doctor Duchamp in 1823 [2], limited progress has been made in understanding the disorder’s pathophysiological mechanism. Although many researchers have tried to set specific diagnostic criteria, the most useful clinical guidelines were created by Petersen [3,4] and completed by Russel and Abu-Arafeh [5]. These specific criteria determine growing pains based on the clinical picture the children present and as recurrent pains of
∗
Corresponding author. E-mail address: [email protected] (A. Kaspiris).
the lower limbs, with a duration of under 72 hours, not accompanied by bone localization or restrictions in the movement of one of more joints and no trauma, oedema, redness, localised sensitivity or other signs of local or generalised inflammation. Although the disorder is quite common, few studies have been published in international literature that examine the epidemiological profile of children presenting these specific pains, which could lead to some useful conclusions as to its aetiology. In a previous study, we examined the influence of breastfeeding on the risk and frequency of growing pains [6]. The aim of the present study is to improve the understanding of the epidemiological data of affected 4- to 12-year olds. In specific, we examine the relationship between growing pains, anthropometric characteristics and the activity levels of the affected children, as well as the diagnostic approach followed.
1297-319X/$ – see front matter © 2009 Société franc¸aise de rhumatologie. Published by Elsevier Masson SAS. All rights reserved. doi:10.1016/j.jbspin.2009.09.001
A. Kaspiris, C. Zafiropoulou / Joint Bone Spine 76 (2009) 486–490
2. Methods This is a retrospective study using questionnaires for the collection of data. It took place from 15 September 2006 to 15 January 2007, during the children’s visits to the paediatric departments of our organisation. By law, children of up to 14 years must be examined by paediatricians and not by GPs. This fact ensures the reliability of our results. Data were collected with the use of semi-structured interviews (a mix of open and closed questions) with parents and children of 4- to 12-year olds, at a frequency corresponding to their daily visits. These visits took place either for routine check-ups and vaccinations, or for the diagnosis and management of some other condition. The sample was representative based on geographical distribution, as it included children from local urban, rurban and rural areas, and social criteria, as arising from the participants’ social insurance. The questionnaire used included questions concerning the appearance of growing pains during the year before the children’s visit to our department, as well as the forms in which they were manifest, the determination of the children’s height, age and weight, frequency of visits to paediatricians or paediatric orthopaedics, the number to conducted examinations, their management as well as their relationship with the children’s activities, the co-existence of other orthopaedic problems or other events, such as a sudden increase in height. The children’s parents were fully briefed as regards the nature and aim of this study and courteously provided their consent thereupon. The whole study complies with the regulations of our organization and the Helsinki Declaration. The study sample includes 532 children, aged 4–12 years, from the area of Achaia, Greece’s third most populous region. Based on the data of the National Statistical Service, the size of the study’s sample, which corresponds to 1.71% of the studied population, allows for the reduction of results for the sum of children in our prefecture. Overall, it was deemed that 130 children presented growing pains, according to Petersen’s criteria. One child was excluded from the study, due to the localization of the pain at the hip and the impaired mobility of the hip, which did not comply with Petersen’s criteria. All data were entered in a Microsoft Excel 2003 file, and were analyzed with the SPSS 13.0 system. To extract conclusions on the results’ statistical significance, we used: Pearson’s Chi-Square Significance Test, with a significance level of 0.05 in combination with Fisher’s Exact Test – for 2 × 2 frequency charts – with a significance level of 0.05.
487
M/F ratio in the sample corresponds to the distribution of the two sexes in the population of this specific age group (4–12 years) in the Prefecture of Achaia, which means no data calculation based on the children’s sex is required. The same holds for the age group ratio. 3. Results The condition’s prevalence is relatively high, corresponding to 24.5% of children. The mean age of the participating children was 8.6 ± 2.5 years, while men height and weight were 132.7 ± 17.1 cm and 34.3 ± 12.8 kg respectively (BMI 1.5 ± 0.6). Although the children usually present these pains between the ages of 3–6, the above age-related finding can be explained by the nature of the study (retrospective), i.e. by the interval between the manifestation of the disease and the completion of the questionnaire. Another important result is that, based on the BMI, there is no statistically significant correlation between the children’s BMI and the appearance of growth pains. Underweight, normal and overweight children all have the same chance of presenting growth pains (Pearson’s Chi-Square p-value = 0.47 > 0.05) (Table 1). The demographic study reveals that the ratio of males to females presenting growing pains is 45:55 respectively. As seen in Table 1 however, there is no significant correlation between the child’s sex and the appearance of the condition (Fisher’s Exact test: p-value = 0.15 > 0.05). The vast majority (90.8%) of children affected by growing pains present these in both legs. 66.9% experience pain during the night while, in 16.2% of these, they lead to nocturnal awakening. A smaller percentage of 11.5% experience even more intense reactions, such as crying. Most incidents of pain (53.1%) appear to take place quite frequently or up to once a month, while they are experienced in their majority (78.5%) after intensive exercise. Their correlation with other events, such as a sudden increase in height or participation on specific sports is not strong. 6.2% of parents report the co-existence of orthopaedic problems, while just 4.2% of participants cannot correlate the pains with any specific aetiological factor (Table 2). A surprising finding is that, despite their increased frequency, only one in five parents visited a doctor for this reason. It is worth noting that neither the frequency nor the type of symptoms affects the frequency of visits to the doctor. For example, the parents of children presenting growing pains with increased
Table 1 Appearance of growing pains in children compared to their BMI. Present pains (n = 130) 24.5
Do not present pains (n = 401) 75.5
Total (n = 531) 100.00
Sex Boys Girls
(n = 61), 21.9 (n = 69), 27.3
(n = 217), 78.1 (n = 184), 72.7
(n = 278), 100.00 (n = 253), 100.00
BMI (kg/m2 ) Underweight Normal Overweight
(n = 63), 23.50 (n = 60), 26.70 (n = 7), 18.4
(n = 205), 76.50 (n = 165), 73.70 (n = 31), 81.6
(n = 268), 100.00 (n = 225), 100.00 (n = 38), 100.00
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A. Kaspiris, C. Zafiropoulou / Joint Bone Spine 76 (2009) 486–490
Table 2 Clinical profile of children presenting growing pains (n = 130). Types of pain presented by the children Nocturnal lower limb pains Nocturnal awakening Crying Pains in other parts of the body
(n = 87), 66.9 (n = 21), 16.2 (n = 15), 11.5 (n = 7), 5.3
Pain frequency Weekly Monthly Quarterly Half-yearly
(n = 36), 28.1 (n = 33), 25.0 (n = 21), 16.4 (n = 40), 30.5
Relationship with physical activities After intensive activity After participation in sports After sudden height increase Linked to orthopaedic problems of the lower limbs (platypodia, valgus knee, uneven limbs) No other cause Frequency of visits to doctor At least once a week Once a month Every trimester Every semester Therapeutic approach Massaging Anti-inflammatory–analgesic agents (paracetamol, acetaminophen, mefenamic acid) Warm compresses Rest Other (reported: ice or plaster applied, etc.)
(n = 102), 78.5 (n = 17), 13.1 (n = 19), 14.6 (n = 8), 6.2 (n = 6), 4.6 (n = 32), 25 (n = 32), 25 (n = 24), 17.9 (n = 42), 32.1 (n = 100), 77.5 (n = 23), 17.5 (n = 18), 13.8 (n = 13), 10.00 (n = 5), 3.80
frequency or with most severe symptomatology, such as nocturnal awakening or crying, do not consult paediatricians more often compared to the parents of children with milder lower limb pains (Pearson Chi-Square test p-value = 0.97 > 0.05). Regarding the specialisations of the doctors the parents consult, the study reveals that 15.3% of parents visit doctors of two different paediatric specialisations. 57.6% consult paediatricians, while a similar percentage visits orthopaedics. Small percentages visit other specialisations, such as rheumatologists or children’s endocrinologists. Finally, just 8.5% of children underwent lab tests (Table 2). The management of growing pains by parents differs, although the most popular treatment appears to be massaging the lower limbs. In some cases, this is done using a local anti-inflammatory cream and/or alcohol. These are followed in popularity by analgesics, warm compresses and rest with a reduction of physical activity (Table 2). 4. Discussion The condition’s prevalence varies and ranges from 2.6 [5] to 49.4% [7]. In a recent study, its prevalence on children in the 4–6 age group was 38.3% [8,9]. In our study, it was 24.5%, in accordance with most writers who report that prevalence is 20% at ages 4–14. Despite attracting the interest of many researchers, the condition’s aetiopathogenicity remains unclear. Four main theories
have been supported. The first is that of rapid skeletal development. The second is the theory of muscular and bone fatigue in highly active children. The third supports that the catalytic factors behind the condition’s appearance include anatomic and orthopaedic problems. Finally, it is believed that these pains may constitute the clinical manifestation of a more generalised pain syndrome that is linked to headaches and abdominal pain, possibly due to psychological stress suffered by the children. In 1823, Duchamp was the first to note that a large number of adolescent children presented an increased frequency of musculoskeletal pains and coined the term “growing pains” to describe them, believed that they were caused by rapid skeletal development [2]. Experimental data presented by Noonan et al. with the implantation of microtransducers at the conjunctive cartilage of the leg of three sheep showed that 90% of bone elongation takes place during lying, a fact consistent with the hypothesis of nocturnal bone elongation and directly linked with growing pains [10]. Epidemiological studies have not confirmed the above finding, as in the study by Evans et al., 35.9% of parents linked growing pains with sudden increases in height [8], while in our study, the corresponding percentage was just 14.6% (Table 2). Subsequently, Bennie adopted the above belief, adding that the catalytic factors for their appearance include intensive physical exercise during the day [11]. This fact was examined by Seham and Hilbert who found an additional relationship between the presence of the pains and insufficient sleep [12]. Indeed, only 15% of children who slept for sufficient hours presented pains, as compared to 34% of children who had not. Intensive physical exercise is linked to their appearance both in the study by Evans et al. at a percentage of 37.8% [8] and in our study, at a much higher percentage of 78.5% in fact (Table 2). Other writers reach similar conclusions for the 4–12 age group, with a percentage of 76%. Analysing a group of 115 children with growing pains, Hawksley reported that they are not linked to rheumatoid fever and concluded that their presence is more frequent in patients with mild orthopaedic conditions, such as platypodia, valgus knee or scoliosis [13]. He also suggested that the term “growing pains” does not accurately describe reality. Other studies however gave only very low percentages to co-existing orthopaedic problems, which amounted to 1.7 or 6.2% in the present study. In the Neish and Apley line in fact, only one out of 168 children presented an orthopaedic disorder (Osgood-Schlatter disease). On the contrary, body weight was significantly higher in children presenting pains, a fact that would support the anatomic theory. This however is not confirmed by our study by using the BMI (Table 1). In addition, neither the clinical measurement of foot posture between children presenting and not presenting growing pains found any significant difference, which also opposes the anatomic theory [14]. Abu-Arafeh hypothesised the existence of a common mechanism with child migraines, as they appeared in children who suffered, or whose parents suffered [15], from migrainetype headaches [5]. In parallel, they had a similar therapeutic approached as they alleviated with the use of analgesics, while 20% improved after sleep. In our research, rest (10%) and the use
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of analgesics (17.5%) also constitute a noteworthy way of managing the condition. This led to the theory that the affected legs present vascular disorders similar to those of migraine. Experimental findings with the use of Tc-99m bone scintiscans and ␥-cameras did not reveal any significant differences in vascular distribution in legs between the two above children’s groups [16]. Their frequent co-existence with other painful conditions, such as abdominal pain, leads to the conclusion that they may be caused by psychological stress. Although the children suffering from the condition have been reported to have high percentages of psychological problems that may reach 62% [17,18], we believe that further investigation in the field of psychosocial theories is required. Recent researches using dolorimeters showed that the pain threshold at the anterior tibia in children with growing pains is lower as compared to others, which relates to the fact that bone density in the painful areas in these children is much lower [19–21]. This finding supports the belief that we are facing a non-inflammatory pain syndrome, but for lower local extremity overuse syndrome with bony fatigue in children with a low pain threshold. These findings may be linked to the protective role played by breastfeeding in the avoidance of growing pains. In specific, a breastfeeding for over 40 days limits the risk of their appearance and modifies their clinical picture [6]. A surprising finding is that, despite their increased frequency, only one in five parents visited a doctor for this reason, irrespectively of the children’s clinical picture (Table 2). The question that arises of course is whether further paraclinical tests are in fact required for diagnosis and treatment. It seems that laboratory tests do not present significant differences between this group and the general population, with the possible exception of white blood cells (WBC) and mean corpuscular volume (MCV) counts, although mean WBC counts were in the normal range in both groups (as were haemoglobin concentrations) and no leucocytosis or leukopenia was noted in the affected children [22]. Judging from the above, we should underline that both lab and X-ray tests are of lesser importance, as a comprehensive history, with interviews with the children and their parents, and a detailed physical examination with a correct implementation of Petersen’s clinical criteria can on their own ensure a satisfactory diagnosis. The differential diagnosis of childhood lower limb pains includes numerous conditions, such as infectious diseases (cellulitis, osteomyelitis, Lyme disease), tumorous diseases (leukaemia, Ewing sarcoma, osteoid osteoma, neuroblastoma), non-inflammatory pain syndromes (fibromyalgia, restless legs syndrome), traumatic aetiology (fractures, joint strain, myositis ossificans), or even rheumatoid conditions (rheumatic fever, juvenile idiopathic arthritis, reactive arthritis) and vascular aetiology (sickle cell crisis, or haemophilia with hemarthrosis) [23]. Similarly, attention must be paid to cases of auto-inflammatory syndromes, which are rare genetic diseases noted by recurrent attacks of inflammation. These syndromes, such as Familial Mediterranean Fever (FMF) – which is common in the Greek population [24] –, Tumour Necrosis Factor (TNF), Receptor
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Periodic Syndrome (TRAPS) and Hyperimmunoglobulinaemia D syndrome (HIDS), which have joint manifestations in about 50% of cases in ages under 10 years [24]. Hence, any other finding, like fever, malaise, weight loss or decreased joint mobility, joint oedema, non-symmetric limb pains, or pains and joint rigidity in the morning, must trigger further lab and X-ray tests. Thus, the diagnosis of growing pains during the appearance of the above clinical signs, which are not included in Petersen’s Criteria (“atypical growing pains”), must only be made after a thorough lab and X-ray investigation and the exclusion of the above diseases. Conflicts of interest None of the authors has any conflicts of interest to declare. References [1] Al Khattat A, Campell J. Recurrent limb pain in childhood (“Growing pains”). Foot 2000;10:117–23. [2] Duchamp M. Maladies de la croissance. In: Levrault FG, editor. Mémoires de médecine practique. Paris: Jean-Frédéric Lobstein; 1823. [3] Petersen H. Leg aches. Pediatr Clin North Am 1977;24:731–6. [4] Petersen H. Growing pains. Pediatr Clin North Am 1986;33: 1365–72. [5] Abu-Arafeh IRG. Recurrent limb pain in school children. Arch Dis Child 1996;74:336–9. [6] Kaspiris A, Zafiropoulou C, Tsadira O, et al. Can breastfeeding avert the appearance of growth pains during childhood? Clin Rheumatol 2007;26:1909–12. [7] Williams MF. Rheumatic conditions in school children. Lancet 1928;211(5458):720–1. [8] Evans AM, Scutter SD, Lang LG, et al. “Growing pains” in young children: a study of the profile, experiences and quality of life issues of four- to six-year-old children with recurrent leg pain. Foot 2006;16:120–4. [9] Evans AM, Scutter SD. Prevalence of “Growing Pains” in young children. J Pediatr 2004;145:255–8. [10] Noonan KJ, Farnum CE, Leiferman EM, et al. Growing pains: are due to increased growth during recumbency as documented in a lamb model? J Pediatr Orthop 2004;24:726–31. [11] Bennie PB. Growing pains. Arch Pediatr 1894;11:337–47. [12] Seham M, Hilbert EH. Muscular rheumatism in childhood. Am J Dis Child 1933;46:826–33. [13] Hawksley JC. The nature of growing pains and their relation to rheumatism in children and adolescents. BMJ 1938;1:155–7. [14] Evans AM, Scutter SD. Are foot posture and fuctional health different in children with growing pains? Pediatr Int 2007;49:991–6. [15] Aroma M, Sillanpaa M, Rautava P, et al. Pain experience of children with headache and their families: a control study. Pediatrics 2000;106: 270–5. [16] Hashles PJ, Gorenberg M, Oren V, et al. “Growing pains” in children are not associated with changes in vascular perfusions patterns in painful regions. Clin Rheumatol 2005;24:342–5. [17] Mikkelson M, Salminen JJ, Kautiainen H. Non-specific musculoskeletal pain in preadolescents. Prevalence and 1-year persistance. Pain 1997;73:29–35. [18] Sherry DD, McGuire T, Mellinns E, et al. Psychosomatic musculoskeletal pain in childhood: clinical and psychological analysis of 100 children. Pediatrics 1991;88:1093–9. [19] Hashkes PJ, Friedland O, Jaber L, et al. Decreased pain threshold in children with growing pains. J Rheumatol 2004;31:610–3. [20] Friedland O, Hashkes PJ, Jaber L, et al. Decreased bone speed of sound in children with growing pains measured by quantitative ultrasound. J Rheumatol 2005;32:1354–7.
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