Ankle Sprain in Children: When a Small Avulsion Changes Recovery Times and Return to Sport
Lateral ankle sprain is one of the most common injuries in athletic children and adolescents. It happens during a game, in the gym, at the park, stepping off a curb, or landing awkwardly after a jump. The ankle "turns," usually inward, and pain appears on the outer side.
Very often the first question is: "Is it just a sprain or is there a fracture?"
In children, however, this distinction can be less clear than it seems. In some cases, the ligament doesn't just tear on its own, but can "pull off" a small bone fragment from the distal fibula. This is known as an avulsion fracture.
A recent study published in the Journal of Pediatric Orthopaedics reported that, in a pediatric case series of lateral ankle injuries, avulsions were present in about a third of patients, with higher frequency in younger children compared to adolescents [1].
The point, however, is not to make a purely radiographic distinction between "sprain" and "small fracture." The point is to understand if this information changes the practical approach: initial protection, weight-bearing, physical therapy, recovery times, and return to sport.
Not all avulsions should be treated as major fractures
In most cases, a small, undisplaced avulsion of the lateral malleolus is treated conservatively.
This means that surgery is not needed and the goal is to protect the ankle during the painful phase, allow tissue healing, and then progressively regain function, strength, and balance.
Options may include:
- functional taping;
- Aircast-type brace;
- walker boot;
- plaster cast or cast in younger children, those in significant pain, or those who are less cooperative;
- progressive weight-bearing according to pain and clinical indication.
There is no single solution. A 7-year-old child in a lot of pain, who cannot bear weight, is not the same as an athletic teenager who is already walking quite well after a few days.
In the clinic, it is common to see two similar X-rays, but two completely different children: one limps a lot, is afraid to bear weight, and has significant swelling; the other walks almost normally. This is where clinical assessment counts at least as much as the image.
First few weeks: protecting the ankle, but with a goal
In stable small lateral avulsions of the distal fibula, the literature and some pediatric guidelines often describe management with a walker/CAM boot-type brace or brief immobilization, with weight-bearing as tolerated, for approximately 3–4 weeks [2,3].
This data needs to be interpreted carefully.
Three or four weeks do not automatically mean "complete healing" or "return to sport." Rather, they indicate the typical duration of the main protection phase: the period during which we expect a progressive reduction in pain, an improvement in walking, and a safer resumption of weight-bearing.
Initial protection should not be seen as a punishment, but as a safety window. It serves to reduce pain, allow the child to walk better, and decrease the risk of them immediately returning to running on an ankle that is still reactive.
At the same time, immobilizing an ankle for too long that could be functionally recovered is not always useful. Stiffness, loss of strength, and fear of movement can become part of the problem.
For this reason, when pain allows, recovery should gradually transition from "protecting" to "reactivating."
From the second to the fourth week: walking well before thinking about sport
A common mistake is to consider the child healed as soon as they can bear weight on their foot.
Walking does not mean being ready for sport.
Between the second and fourth week, in uncomplicated cases, the practical goals are:
- walking without a limp;
- reduction of swelling;
- recovery of ankle mobility;
- progressive discontinuation of the brace, if indicated;
- initiation of simple strengthening and control exercises;
- recovery of single-leg balance.
If the child is still walking poorly, avoiding weight-bearing, or reporting significant lateral pain, it is premature to talk about running, jumping, or playing a game.
This is particularly important because distal fibula avulsions are not always an irrelevant finding. Yamaguchi and colleagues observed that, after ankle sprain in childhood, the presence of a distal fibula avulsion was associated with a higher risk of recurrent sprains [4].
This does not mean that every child with an avulsion will develop instability. However, it does mean that the functional recovery phase should not be skipped.
Fourth-sixth week: return to daily life, not necessarily to sport
More generally, pediatric ankle fractures tend to heal in about 4–6 weeks, although this data includes injuries of different locations and severities [5].
For many small, stable avulsions, this is the phase where the child progressively returns to daily normality: school, stairs, safer walking, light activities.
But "daily life" and "sport" are not the same thing.
An ankle may be fine for walking in class, but not yet ready for a soccer game, a basketball practice, a volleyball jump, or an intense dance lesson.
This phase should serve to recover:
- strength of the peroneal muscles;
- complete or near-complete mobility;
- single-leg balance;
- control during weight-bearing;
- confidence in movement;
- ability to run without pain.
This is often the phase that is skipped, because the pain decreases and the child "seems healed." But it is precisely here that an important part of recurrence prevention is built.
Return to sport: functional criteria are better than fixed dates
For more significant lateral sprains, some pediatric guidelines indicate that sufficient recovery to return to sport may require 5–10 weeks, even with an adequate rehabilitation program [6].
This is a central point.
It is not correct to say that all children with a small avulsion return to sport after 4 weeks. Some recover quickly, others need more time, especially if they play sports with jumping, sprinting, changes of direction, rotations, or contact.
Return to sport should not be decided solely based on the X-ray or the number of weeks passed. It should primarily be based on function.
Before returning, the following should be present:
- walking without a limp;
- running without pain;
- absence of swelling after activity;
- mobility similar to the healthy side;
- good single-leg balance;
- controlled jumps;
- changes of direction without giving way;
- absence of obvious fear during weight-bearing.
For a child who plays soccer, for example, it is not enough to walk without pain: they must tolerate running, braking, changes of direction, single-leg weight-bearing, and contact with the ball. For those who play basketball or volleyball, the main problem may be landing after a jump. For dance and gymnastics, control, range of motion, and confidence in the movement come into play.
In some children, residual pain and swelling can last longer, even several months, despite an overall favorable outcome [7]. This should not be alarming, but it helps explain why recovery does not always follow perfectly linear timelines.
What if a small bone remains near the malleolus?
After a sprain or a small avulsion, a small bone fragment may remain visible over time near the tip of the fibula. In some cases, it is an asymptomatic finding; in others, it can create doubts in subsequent X-rays, especially after new traumas.
Pediatric studies have suggested that a portion of subfibular ossicles may have a post-traumatic origin, meaning they are the result of previous avulsions [8]. More recently, Li and colleagues emphasized that distinguishing an acute avulsion from a subfibular ossicle can be complex and that dynamic ultrasound can help in selected cases [9].
For parents, however, the practical message is simple: if a child has persistent pain, repeated sprains, or a feeling of giving way, it is not enough to say "there's a small bone." It is necessary to understand if that finding is truly irrelevant or if it is part of the clinical problem.
When to re-evaluate
In most cases, the outcome is favorable. However, it is prudent to re-evaluate if:
- the child is still unable to bear weight after a few days;
- lateral pain remains significant;
- swelling does not improve;
- nocturnal or progressive pain appears;
- limping persists longer than expected;
- the ankle "gives way";
- repeated sprains occur;
- the child is unable to resume running or jumping.
The initial X-ray is important, but it does not always conclude the reasoning. Some studies have shown that distal fibula avulsions can be difficult to recognize in the early stages and that ultrasound or re-evaluation may play a role in doubtful cases or those with an inconsistent course [10].
The final message
A small lateral ankle avulsion should not be alarming, but it should not be trivialized either.
In most cases, treatment is conservative and the prognosis is good. However, initial protection, progressive recovery, and function-guided return to sport are essential to reduce the risk of recurrence and persistent pain.
The question is not just: "Is it a fracture or a sprain?"
The more useful question is: is this ankle ready to do what the child asks of it?
Bibliographic References
[1] Jones J, Schultz C, Lampe K, Van Pelt B, Podvin C, Miller S, Chung J, Wyatt C, Johnson B, Ellis H, Wilson P. Pediatric Lateral Ankle Avulsion Fractures: Age-Specific Patterns and Diagnostic Clues. J Pediatr Orthop. 2026;46(1):6-12. doi:10.1097/BPO.0000000000003078. PMID: 40778671.
PubMed: https://pubmed.ncbi.nlm.nih.gov/40778671/
[2] Su AW, Larson AN. Pediatric Ankle Fractures: Concepts and Treatment Principles. Foot Ankle Clin. 2015;20(4):705-719. doi:10.1016/j.fcl.2015.07.004. PMID: 26589088.
PubMed: https://pubmed.ncbi.nlm.nih.gov/26589088/
[3] Perth Children’s Hospital. Fractures — Ankle. Emergency Department Guideline.
[4] Yamaguchi S, Akagi R, Kimura S, Sadamasu A, Nakagawa R, Sato Y, Kamegaya M, Sasho T, Ohtori S. Avulsion fracture of the distal fibula is associated with recurrent sprain after ankle sprain in children. Knee Surg Sports Traumatol Arthrosc. 2019;27:2774-2780. doi:10.1007/s00167-018-5055-7. PMID: 29992464.
PubMed: https://pubmed.ncbi.nlm.nih.gov/29992464/
[5] American Academy of Orthopaedic Surgeons. Ankle Fractures in Children. OrthoInfo.
Link: https://orthoinfo.aaos.org/en/diseases–conditions/ankle-fractures-in-children/
[6] Royal Children’s Hospital Melbourne. Ankle Sprains — Emergency Department Clinical Practice Guideline.
Link: https://www.rch.org.au/clinicalguide/guideline_index/fractures/Ankle_Sprains_-_Emergency_Department/
[7] Cambridge University Hospitals NHS Foundation Trust. Ankle sprains and avulsion fractures in children.
Link: https://www.cuh.nhs.uk/patient-information/ankle-sprains-and-avulsion-fractures-in-children/
[8] Lee DY, et al. Posttraumatic Subfibular Ossicle Formation in Children. J Pediatr Orthop. 2018.
[9] Li X, et al. Lateral Ankle Avulsion Fracture Versus Subfibular Ossicles in Pediatric Lateral Ankle Sprain: A Novel Dynamic Ultrasonographic Technique. J Pediatr Orthop. 2026. doi:10.1097/BPO.0000000000003094.
[10] Takakura Y, Yamaguchi S, Akagi R, Kimura S, Tanaka H, Yasui T. Diagnosis of avulsion fractures of the distal fibula after lateral ankle sprain in children: a diagnostic accuracy study comparing ultrasonography with radiography. BMC Musculoskelet Disord. 2020;21:276. doi:10.1186/s12891-020-03287-1. PMID: 32345266.
PubMed: https://pubmed.ncbi.nlm.nih.gov/32345266/
Disclaimer: content for general informational purposes only. It does not replace a medical evaluation.
