Can Growing Pains Be in One Leg? Signs & What to Do

Growing pains are classically described as bilateral, meaning they affect both legs, and pain that stays in a single leg is considered atypical enough to warrant a closer look. The standard diagnostic criteria, used since the 1980s, specifically note that the discomfort is “almost always bilateral.”¹ That does not mean a child never feels one leg aching more on a given night, but persistent, recurring pain limited to one leg is a signal that something else may be going on. Sorting out what qualifies as growing pains, what does not, and when to see a doctor is more nuanced than most parents expect.

What Growing Pains Actually Look Like

The term “growing pains” dates to the nineteenth century and, despite its staying power, has no proven connection to physical growth.² Children do not seem to grow faster during painful episodes, and tall children are no more likely to get them than short ones. The name simply stuck because the pain tends to show up during the growth-heavy years of early and middle childhood, roughly ages three through twelve.

Despite decades of research, there is no universally agreed-upon set of diagnostic criteria. A scoping review found that only about 62% of published studies on growing pains even reported diagnostic criteria, and among those that did, the criteria varied considerably.³ The most commonly used set, described by Peterson in 1986, outlines a fairly specific pattern: intermittent pain occurring once or twice per week, typically in the late afternoon or at night; non-articular pain located mostly in the shins, calves, thighs, or behind the knee; resolution by the next morning; and no visible signs of inflammation such as swelling, redness, or warmth.¹ Crucially, those criteria describe the pain as almost always bilateral. A survey of Australian children aged four to six estimated that about 37% met the definition of recurrent leg pains consistent with growing pains, making this an extremely common childhood complaint.⁴

When Pain Is Only in One Leg

During any single episode, a child might feel the ache more on one side. That, on its own, is not alarming. Growing pains can shift around from night to night, and a child may complain about the left calf one evening and both thighs the next. The concern arises when the pain is consistently, repeatedly isolated to one leg over many episodes. In that pattern, the diagnosis of growing pains becomes less likely, because the hallmark of the condition is its vague, shifting, bilateral quality.

Unilateral leg pain in a child opens a broader list of possibilities. Some are benign and mechanical. Others require urgent attention. The rest of this article walks through both categories, along with what you can do at home and when to seek medical help.

Red Flags That Point Away from Growing Pains

Pediatric guidelines identify several warning signs that should prompt an urgent medical visit rather than a wait-and-see approach. These include persistent or worsening pain, fever or unexplained weight loss, pain that wakes a child from deep sleep and does not respond to comfort, refusal to bear weight on the affected leg, and visible swelling or redness over a joint or bone.⁵ Pain that is disproportionate to any visible injury is another red flag.

A limp deserves special attention. Growing pains, by definition, do not cause limping. If a child is favoring one leg during the day, something structural or inflammatory is likely involved. Similarly, growing pains do not cause joint pain. The ache is felt deep in the muscles of the leg, not in the knee or ankle joint itself. Joint pain, especially with swelling, moves the conversation into a different diagnostic territory entirely.

One point that surprises many parents: growing pains are not supposed to still be there in the morning. A child who wakes up and the pain has vanished fits the classic profile. A child who limps to the breakfast table does not.

Conditions That Can Mimic Growing Pains in One Leg

When a child has recurrent pain isolated to one leg, several conditions are worth considering. Some are common and manageable; a few are rare but serious.

Overuse Injuries and Traction Apophysitis

Active kids, especially young athletes, are prone to overuse injuries at the growth plates where tendons attach to bone. These conditions have intimidating names but are usually straightforward. Osgood-Schlatter disease causes a tender bump just below the knee, and Sinding-Larsen-Johansson disease affects the lower edge of the kneecap. Both are common in the lower extremities of adolescent athletes and can limit sport participation and cause prolonged pain.⁶ These conditions are typically one-sided or at least much worse on one side, which is a key distinction from growing pains. They also produce tenderness at a specific spot you can point to, while growing pains tend to be diffuse and hard to localize.

Stress Fractures and Toddler’s Fractures

In younger children, a subtle spiral fracture of the tibia, called a toddler’s fracture, can cause pain and limping without any obvious injury event. These can be hard to detect on initial X-rays. Clinical examination involves carefully pressing along the entire length of the shinbone in small increments to find the tender spot.⁷ In older, active children, stress fractures from repetitive impact can produce a similar picture of one-sided leg pain that worsens with activity.

Infections and Inflammatory Conditions

Bone or joint infections (osteomyelitis and septic arthritis) tend to be dramatic, with fever, swelling, and severe pain, but early stages can sometimes be mistaken for a sore leg. In regions where Lyme disease is common, Lyme arthritis should be on the radar for a child with swelling in one knee or ankle. Lyme arthritis typically affects one joint or just a few joints and is an important consideration in endemic areas.⁸

Rare but Serious Causes

Very occasionally, limping or leg pain in a child turns out to be the first sign of something like leukemia. In a case series of children who presented to emergency departments with limping, acute leukemia was eventually diagnosed. The limb pain in those cases was highly variable, X-rays were normal, and early blood tests sometimes failed to show obvious abnormalities.⁹ This is rare, but it underscores why persistent, unexplained, one-sided leg pain should be evaluated by a doctor rather than assumed to be growing pains.

Why Growing Pains Happen at All

This is an area where the science is genuinely thin. Despite how common growing pains are, researchers still do not agree on a single cause. Several theories coexist, and the honest answer is that more than one factor probably contributes.

One line of research points to how the nervous system processes pain signals. Children with growing pains show heightened sensitivity to cold, vibration, and deep pressure compared to children without the condition, and this heightened response is widespread across the body rather than limited to the legs. That pattern suggests a mild, generalized change in how the central nervous system handles sensory input rather than a localized muscle or bone problem.¹⁰ In other words, the pain may be real and felt in the legs, but the underlying issue could be a temporarily lower pain threshold in the brain and spinal cord rather than actual tissue damage in the muscles.

Another hypothesis involves foot mechanics. Some researchers have noted that children with growing pains often have feet that roll inward more than usual during walking. Treating this with supportive shoe inserts has been reported by parents and children to reduce or even eliminate painful episodes in small studies.¹¹ This does not prove that foot posture causes growing pains, but it raises the possibility that biomechanical stress on fatigued muscles plays at least a supporting role. If a child’s foot mechanics differ between the two sides, this might also help explain why one leg occasionally hurts more than the other.

The Restless Legs Connection

Growing pains and restless legs syndrome in children share enough features that researchers have spent years trying to figure out whether they are different faces of the same condition. Both tend to worsen in the evening, involve uncomfortable sensations in the legs, and can disrupt sleep. A side-by-side comparison of their diagnostic criteria found significant overlap, with abnormalities in vitamin D metabolism potentially common to both.¹²

Iron and vitamin D appear to be threads running through both conditions. Research has found associations between growing pains and iron deficiency, and one study reported that low vitamin D levels were present in a large majority of patients with either restless legs syndrome or growing pains.¹³ Whether correcting these deficiencies actually reduces symptoms is still being studied, but it gives parents something concrete to discuss with a pediatrician, especially if a child’s diet is limited or they get little sun exposure.

Restless legs syndrome, unlike growing pains, involves an irresistible urge to move the legs rather than pure aching. If your child describes their discomfort more as a creepy-crawly feeling that gets better with movement than as a deep ache that just sits there, it is worth mentioning this to their doctor.

What to Do When Your Child’s Legs Hurt

For pain that fits the growing pains profile — both legs, evening or nighttime, no limping, gone by morning — home care is the first step. Gentle massage, a warm bath, or a heating pad on the sore muscles often helps. Stretching the calf and thigh muscles before bed has also become a popular recommendation, though the formal evidence base is slim. Many parents report these methods provide enough relief for a child to fall back asleep.

When comfort measures are not enough, over-the-counter pain relievers like ibuprofen or acetaminophen at weight-appropriate doses are a reasonable option. If one medication alone is not controlling the pain, some practitioners suggest alternating between the two, but this approach lacks solid long-term safety data and should be used for short stretches rather than as a nightly routine.¹⁴ Before escalating to an alternating regimen, it is worth making sure the single medication is being given at an adequate dose and at the right time interval — underdosing is a surprisingly common reason pain relief seems to fail.

For children whose growing pains are frequent and disruptive, keeping a pain diary can be useful. Recording which leg hurts, when the pain started, how long it lasted, what the child did that day, and what helped can reveal patterns. It also gives a pediatrician something concrete to work with if the picture starts to look less like growing pains and more like something else.

When to See the Doctor

A single episode of one-sided leg pain after a busy day of running around does not necessarily warrant a clinic visit. But a pattern of pain that consistently stays on one side deserves medical attention. The same goes for any of the red flags already mentioned: limping, joint swelling, fever, morning pain that does not resolve, refusal to put weight on the leg, or pain that seems out of proportion to any activity.

A doctor evaluating a child with persistent leg pain will typically start with a thorough physical exam, checking for point tenderness along bones, joint range of motion, and signs of inflammation. They may press along the tibia in small increments or watch the child walk. Blood tests and imaging are not always needed but become important when the history or exam raises concerns. As noted earlier, some serious conditions like early-stage leukemia can present with normal X-rays and initially unremarkable blood work,⁹ so follow-up visits matter if symptoms persist or evolve.

The reassuring news is that true growing pains, while annoying and sometimes genuinely distressing for a child, are considered a benign condition with a generally good outcome.¹⁵ Most children outgrow them entirely. The goal of the medical evaluation, when one is needed, is not to prove your child has growing pains. It is to rule out the things that are not growing pains.

The Problem with the Diagnosis Itself

Growing pains occupy an unusual space in medicine. They are one of the most common childhood pain complaints, yet there is no objective test to confirm them. The diagnosis is made by exclusion: if the pain fits the general profile and nothing else turns up on examination, the label gets applied. This makes many pediatric researchers uncomfortable, and the lack of standardized criteria means that one doctor’s growing pains might be another doctor’s “investigate further.”

The scoping review that found only about 62% of studies reported diagnostic criteria also found that when criteria were reported, they varied widely.³ Some included age ranges, some did not. Some required the pain to affect physical activity, others did not mention it. This inconsistency means that research findings from one study may not cleanly apply to the children diagnosed in another, and it makes giving parents a crisp, definitive answer harder than it should be.

The sensory processing research adds another layer of complexity. If growing pains are at least partly a central nervous system phenomenon rather than a purely muscular one,¹⁰ then the traditional framing of “just muscle aches from an active day” may be selling the condition short. A child who genuinely has a lower pain threshold is experiencing real distress, not being dramatic. This perspective can change how parents respond to nighttime complaints: less “it’s nothing, go back to sleep” and more “let me help you through this.” That shift in approach does not cost anything, and for a child woken up by aching legs at two in the morning, it matters a great deal.

Foot Posture and Practical Interventions

The link between how a child’s foot hits the ground and growing pains has not been studied in large trials, but the early findings are interesting enough to mention. Children whose feet roll inward excessively during walking put different stresses on the muscles of the lower leg compared to children with a more neutral foot posture. In small clinical studies, correcting this with in-shoe devices reduced or eliminated episodes of aching legs.¹¹

This does not mean every child with growing pains needs orthotics. But if your child’s shoes wear down unevenly on the inner edge, or if they seem flat-footed, a conversation with a podiatrist or pediatric orthopedist could be worthwhile. At the very least, making sure a physically active child wears supportive footwear rather than flat, unsupported shoes is a low-risk, no-cost step. If foot mechanics contribute to muscle fatigue that feeds into the pain, addressing it may also help explain asymmetric discomfort: a foot that pronates more on one side could plausibly contribute to more pain on that side.

1
PubMed Central. Growing pains: What do we know about etiology? A systematic review
2
Pediatrics. Defining Growing Pains: A Scoping Review
3
BMJ Open. Assessments, diagnostic criteria and outcome measures for growing pains and persistent pain in the presence of restless leg syndrome in children: a scoping review
4
The Journal of Pediatrics. Prevalence of “Growing Pains” in Young Children
5
PubMed Central. The limping child – when to worry and when to refer: a GP’s guide
6
Sports & Exercise Medicine Switzerland. Traction apophysitis
7
PubMed Central. Limp
8
PubMed Central. Lyme disease and the orthopaedic implications of lyme arthritis
9
PubMed. Pediatric leukemia revealed by a limping episode: a report of four cases
10
PubMed Central. Somatosensory test responses in children with growing pains
11
PubMed. Relationship between “growing pains” and foot posture in children: single-case experimental designs in clinical practice
12
PubMed. Restless legs syndrome (Willis-Ekbom disease) and growing pains: are they the same thing? A side-by-side comparison of the diagnostic criteria for both and recommendations for future research
13
PubMed Central. Restless legs syndrome and growing pains in childhood: understanding the link
14
PubMed Central. Alternating acetaminophen and ibuprofen for pain in children
15
PubMed Central. Growing pains in children