What Are Growing Pains?
Growing pains are recurrent episodes of musculoskeletal pain in the lower limbs that affect children, typically between 3 and 12 years of age. Despite the name, there is no evidence that these pains are related to the growth process. It is a diagnosis of exclusion, established when pathologic causes are ruled out.
First described in 1823, growing pains are the most common cause of recurrent musculoskeletal pain in childhood. They are characterized by bilateral lower limb pain, predominantly nocturnal, that is not associated with inflammatory signs, laboratory abnormalities, or imaging findings. The child is completely well during the day.
Nocturnal Pattern
Pain in the evening or at night, with the child completely asymptomatic in the morning and throughout the day
Location
Bilateral lower limbs — anterior thighs, calves, and behind the knees, never in the joints
Diagnosis
Diagnosis of exclusion — normal physical examination, no inflammatory signs, normal laboratory tests
Reassurance
Benign, self-limited condition — causes no musculoskeletal damage and resolves spontaneously
Pathophysiology
The exact cause of growing pains remains unknown. The most traditional theory — that the pain results from rapid bone growth — is not supported by evidence. Studies demonstrate that growth velocity does not correlate with the frequency or intensity of pain episodes.
The most accepted hypotheses currently include: (1) muscle fatigue from intense physical activity during the day, leading to nocturnal muscle pain; (2) decreased pain threshold in these children, suggesting a component of central sensitization; (3) joint hypermobility in some affected children; and (4) psychosocial factors such as anxiety and personality profile.
PATHOPHYSIOLOGIC HYPOTHESES
| HYPOTHESIS | EVIDENCE | COMMENT |
|---|---|---|
| Muscle overload (physical activity) | Moderate | Pain more frequent on days of greater physical activity |
| Reduced pain threshold | Moderate | Children with growing pains have lower pressure tolerance |
| Joint hypermobility | Low-moderate | Present in some children, but not in all |
| Vitamin D deficiency | Low | Some studies show an association, but no clear causal link |
| Psychological factors | Low-moderate | Association with anxiety and perfectionism in some studies |
| Bone growth per se | Not supported | No correlation with growth velocity |
Recent studies suggest that children with growing pains have a significantly lower pressure pain threshold than healthy controls, not only in the lower limbs, but also in sites unaffected by pain. This suggests an altered central pain processing component, similar to that observed in functional pain syndromes in adults.
Symptoms
The clinical picture is quite characteristic: the child complains of leg pain in the evening or wakes during the night with pain, crying, and a need for parental comfort. In the morning, the child is completely asymptomatic, without any limitation. The pain is never articular — it is located in the muscles of the thighs, calves, and posterior region of the knees.
- 01
Bilateral lower limb pain (thighs, calves, behind the knees)
- 02
Pain in the evening or during the night
- 03
Child completely well during the day
- 04
Intermittent episodes with symptom-free days
- 05
Pain that improves with massage and local heat
- 06
No edema, erythema, or heat in the painful areas
- 07
Completely normal physical examination
- 08
Episodes more frequent on days of greater physical activity
Diagnosis
Diagnosis of growing pains is one of exclusion. It is based on the presence of the typical clinical picture (bilateral nocturnal lower limb pain, child well during the day, normal physical examination) and on the absence of warning signs that suggest underlying pathology.
🏥Diagnostic Criteria (Peterson, modified)
- 1.Bilateral and intermittent lower limb pain
- 2.Predominantly nocturnal or evening pain
- 3.Absence of pain during the day — no limp
- 4.Completely normal musculoskeletal physical examination
- 5.Non-articular pain (muscular — thighs, calves, behind the knees)
- 6.Episodes last minutes to hours, with symptom-free periods in between
- 7.No fever, weight loss, or other systemic signs
Differential Diagnosis
Growing pains are a diagnosis of exclusion: any deviation from the classic pattern requires workup for serious conditions. Recognizing warning signs and knowing when to investigate is the most critical clinical skill in managing pediatric musculoskeletal pain.
DIAGNÓSTICO DIFERENCIAL
Differential Diagnosis
Leukemia (Bone Pain)
- Intense and diffuse bone pain
- Fever, pallor, ecchymoses
- Leukocytosis or bicytopenia
- Fever + bone pain in a child = urgent hematologic evaluation
Testes Diagnósticos
- Complete blood count
- LDH
- Radiograph
Juvenile Idiopathic Arthritis
- Objective arthritis: swelling, heat, joint redness
- Morning stiffness
- Persistent for more than 6 weeks
Testes Diagnósticos
- ESR
- CRP
- ANA
- Radiograph
Osteosarcoma and Bone Tumors
- Progressive and continuous pain, not just at night
- Palpable mass
- Adolescents with rapid growth
- Palpable bone mass = immediate workup
Testes Diagnósticos
- Radiograph
- MRI
- Biopsy
Osgood-Schlatter Disease
- Pain and prominence at the anterior tibial tuberosity
- Worsens with physical activity
- Active adolescents
Testes Diagnósticos
- Lateral knee radiograph
Benign Joint Hypermobility
- Hypermobile joints
- Diffuse post-activity pain
- Elevated Beighton score
Testes Diagnósticos
- Beighton score
- Exclusion of organic causes
Leukemia and bone tumors: when pain cannot wait
Bone pain in childhood leukemia is frequently the first symptom, appearing before evident hematologic manifestations such as pallor and ecchymoses. A child with leukemia may present with bilateral nocturnal lower-limb pain, perfectly mimicking growing pains. The distinguishing signs are: persistent daytime pain, bone pain on palpation, fever without apparent focus, pallor, spontaneous ecchymoses, and hepatosplenomegaly. A complete blood count with LDH is the first investigative step.
Bone tumors — osteosarcoma and Ewing sarcoma — predominate in adolescents during the growth spurt. The pain is progressive, continuous (not just nocturnal), and frequently associated with a palpable firm mass. Plain radiograph is the first imaging examination, possibly showing an osteolytic lesion, "onion-skin" periosteal reaction (Ewing), or Codman triangle (osteosarcoma). Any palpable bone mass in a child or adolescent requires immediate workup.
Juvenile idiopathic arthritis: the arthritis that cannot be missed
Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in childhood and may present with lower-limb pain that is confused with growing pains. The fundamental distinction is that JIA causes objective arthritis — swelling, heat, and limitation of joint movement — and not just muscle pain. Prolonged morning stiffness (more than 30 minutes), improvement of pain with movement throughout the day, and involvement of specific joints are characteristics of JIA.
The workup includes ESR, CRP, complete blood count, and ANA (which may be positive in some JIA subtypes). Radiographs in early phases may be normal. Diagnosis requires arthritis in one or more joints for at least 6 weeks, with exclusion of other causes. Referral to a pediatric rheumatologist is indicated when JIA is suspected, since early treatment prevents joint and ocular sequelae (uveitis).
Osgood-Schlatter disease and hypermobility: benign conditions to recognize
Osgood-Schlatter disease is an apophysitis of the anterior tibial tuberosity, caused by repetitive traction of the patellar tendon during accelerated bone growth. It differs from growing pains by precise localization at the anterior tibial tuberosity (a palpable, painful bony prominence), by worsening with physical activity, and by its presence in active adolescents between 10 and 15 years. The lateral knee radiograph confirms the diagnosis by showing fragmentation of the tuberosity.
Benign joint hypermobility syndrome is diagnosed by the Beighton score, which assesses range of motion at five anatomic points. Hypermobile children may have diffuse post-activity pain without structural pathologic cause, and diagnosis is made by exclusion. Treatment focuses on muscle strengthening and proprioception to stabilize hypermobile joints, without need for activity restriction.
Treatment
The pillar of treatment of growing pains is reassurance of parents and child. It is fundamental to explain that the condition is benign, self-limited, and that it does not cause any damage to the musculoskeletal system. Simple measures are effective for relief of episodes.
During the Pain Episode
Gentle massage of painful areas, local heat (heating pad), emotional comfort. Simple analgesic (acetaminophen or ibuprofen) for intense pain.
Preventive Measures
Lower-limb stretching before sleep (quadriceps, hamstrings, calves). May reduce episode frequency in some patients, according to observational studies.
Assessment of Contributing Factors
Check vitamin D levels. Assess the child's physical activity (overload). Consider psychological evaluation if significant anxiety.
Follow-up
Clinical follow-up for reassessment. Episodes tend to space out and stop between ages 10 and 12.
THERAPEUTIC MEASURES AND EVIDENCE
| MEASURE | EVIDENCE | PRACTICAL GUIDANCE |
|---|---|---|
| Reassurance and education | High | Most important component of treatment |
| Local massage | Moderate | Relief during episode — parents can perform |
| Local heat | Low (practice-based) | Heating pad or warm bath before sleep |
| Stretching before sleep | Moderate | Quadriceps, hamstrings, and calves — 10 minutes |
| Acetaminophen/Ibuprofen | Moderate | For more intense episodes — weight-based dose |
| Vitamin D | Low | Supplement if proven deficiency |
Acupuncture as Treatment
Acupuncture may be considered as a complementary option in children with frequent growing pains that significantly impact sleep and quality of life. The approach in children uses adapted techniques — finer needles, shorter dwell time and, in some cases, non-invasive techniques such as laser acupuncture or acupressure.
Proposed mechanisms include pain modulation through endogenous opioidergic pathways, regulation of muscle tone, and a potential effect on pain-threshold modulation — which is altered in these children. Auriculotherapy with seeds (non-invasive) may be an alternative well accepted by children and parents.
Prognosis
The prognosis of growing pains is excellent. The condition is benign, self-limited, and causes no sequelae in the musculoskeletal system. Most children show spontaneous resolution of episodes between 10 and 12 years of age, although some may have symptoms that persist into adolescence.
Long-term follow-up studies suggest that children with growing pains may have a greater predisposition to functional pain syndromes in adult life, such as fibromyalgia and tension-type headache. This reinforces the hypothesis that these children have altered central pain processing.
Myths and Facts
Myth vs. Fact
Growing pains are caused by the growth of bones.
No evidence shows that bone growth causes pain. The name is historical and imprecise. The most likely causes involve muscle fatigue and altered pain processing.
Growing pains indicate calcium deficiency.
No proven link exists between growing pains and calcium deficiency. Calcium supplementation neither prevents nor treats the episodes.
The child is making up the pain to get attention.
The pain is real and can be very intense. Studies using objective pain tests confirm that these children have a reduced pain threshold. Dismissing the complaint is harmful.
Children with growing pains will grow more.
No correlation exists between growing pains and final height. Growth velocity is normal in these children.
When to Seek Medical Help
Frequently Asked Questions
Growing Pains: Common Questions
Growing pains are real — studies using objective pain-assessment instruments confirm that these children have a reduced pain threshold and altered central pain processing. Despite the imprecise historical name, the condition is clinically recognized and well documented, affecting 10-36% of school-age children.
Growing pains mainly affect children between 3 and 12 years, peaking between 4-6 years. Most cases resolve spontaneously between ages 10 and 12. Some children have symptoms that extend into adolescence. Onset before age 3 or after age 12 warrants investigation of other causes.
Nightly episodes lasting more than 2 consecutive weeks warrant medical evaluation. An intense nocturnal pattern may suggest other conditions such as juvenile idiopathic arthritis or, rarely, bone tumors (such as osteoid osteoma, which causes characteristic nocturnal pain that resolves with anti-inflammatories). A medical visit for physical examination and, if necessary, laboratory tests is recommended.
In the typical clinical picture (child between 3 and 12 years, bilateral nocturnal lower-limb pain, completely asymptomatic during the day, normal physical examination), tests are not necessary. Workup is indicated when warning signs appear: daytime pain, arthritis, fever, pallor, weight loss, persistent unilateral pain, or atypical onset.
The most effective measures during an episode are: gentle massage of the painful areas (calves, thighs, behind the knees), local heat (heating pad or warm bath), emotional comfort, and, if pain is intense, acetaminophen or ibuprofen at the correct weight-based dose. These measures usually bring relief within 15-30 minutes.
Observational studies suggest that daily lower-limb stretching before sleep can reduce episode frequency in some children. The protocol consists of quadriceps, hamstring, and calf stretches held for 20-30 seconds each, performed for at least 4 weeks. It is a simple, safe measure backed by moderate-quality evidence.
Scientific evidence does not support a link with calcium deficiency. Some studies associate growing pains with vitamin D deficiency, but without a clear causal relationship. If vitamin D deficiency is suspected (low sun exposure, restrictive diet), the serum level can be ordered and supplementation considered if deficient.
Yes, as a complementary option in frequent cases that disrupt sleep and quality of life. Non-invasive techniques such as laser acupuncture, acupressure, and auriculotherapy with seeds are preferable for younger children; fine needles with shorter dwell time can be used in older children with good acceptance. The medical acupuncturist will assess the indication and the most appropriate technique for each child.
Growing pains cause no musculoskeletal sequelae. However, follow-up studies suggest that affected children may have a greater predisposition to functional pain syndromes in adult life, such as fibromyalgia and tension-type headache, reflecting an altered central pain-processing pattern.
Yes — physical activity is not contraindicated. In some cases, more active days can trigger nocturnal episodes, but this does not mean sport should be avoided. The benefits of physical activity far outweigh this inconvenience. Pre-sleep stretches are especially important on more active days.