Is It an Ankle Sprain or a Growth Plate Injury in Children?
In children, ankle injuries are often growth plate (Salter-Harris) injuries rather than ligament sprains, because growth plates are weaker than ligaments.
If your child has pain directly over the bone, struggles to weight bear, or symptoms don’t improve within a few days, they should be assessed and, in some cases, may require referral to a consultant or MRI imaging.
Introduction: Why This Isn’t “Just a Sprain”
When a child rolls their ankle, most people assume it’s a sprain.
But in growing children:
The same injury that causes a sprain in an adult can cause a growth plate injury in a child.
This is one of the most important concepts in paediatric injury care and one of the most commonly misunderstood.
Children Aren’t Mini Adults (Key Concept)
In adults:
- Ligaments are the weakest structure Injury = sprain
In children:
- Growth plates are the weakest structure Injury = often a Salter-Harris injury
Growth Plate Closure (Critical Detail)
At the ankle (distal tibia):
- Boys: growth plate often remains open until 17-18 years
- Girls: typically closes around 15-16 years
Meaning many teenagers are still at risk of growth plate injury
What Is an Ankle Sprain?
A sprain is:
- A stretch or tear of ligaments
- Usually on the outside of the ankle
Typical signs
- Pain around soft tissue
- Swelling and bruising
- Able to walk (often with discomfort)
- Gradual improvement over a few days
What Is a Salter-Harris (Growth Plate) Injury?
A Salter-Harris injury affects: The growth plate (physis) of the bone
This area is:
- Softer
- Still developing
- More vulnerable to force
Why Growth Plate Injuries Are Often Missed
- Symptoms overlap with sprains
- X-rays can be normal (especially Type I)
- Assumption = “just a sprain”
This is where clinical expertise matters
Key Differences: Sprain vs Growth Plate Injury
Feature Sprain Growth Plate Injury
Tissue Ligament Bone (growth plate)
Pain Around ankle Directly over bone
Walking Often possible Often difficult
Recovery Improves steadily May not improve as expected
Imaging Not usually needed May need X-ray/MRI
Simple Parent Flow Guide
1. Where is the pain?
- Soft area → likely sprain
- Directly on bone → consider growth plate
2. Can they weight bear?
- Yes → monitor
- No → need to go to A and E
3. After 3–5 days
- Improving → likely sprain
- Not improving → needs review with a medical professional
If unsure → always get it checked
When Is Referral or MRI Needed?
Most injuries are managed clinically but referral may be needed if:
- Pain persists beyond 7-10 days
- Child cannot weight bear
- Diagnosis is unclear
- Symptoms don’t match a simple sprain
MRI May Be Used When:
- X-ray is normal but pain persists
- Salter-Harris Type I suspected
- Deeper injury needs assessment
MRI shows:
- Growth plate detail
- Bone stress
- Soft tissue involvement
What Happens If a Growth Plate Injury Is Missed?
Most cases are not dangerous but missing one can lead to:
1. Prolonged Pain
- Symptoms linger
- Activity becomes difficult
2. Delayed Recovery
- Longer time away from sport
- Frustration for child and parent
3. Recurrent Problems
- Area becomes repeatedly irritated
4. Growth Plate Disruption (Rare but Important)
In more significant cases:
- Growth may be affected
- Bone may develop unevenly
Possible outcomes (rare):
- Angular deformity
- Limb length differences
Rare but why early diagnosis matters
Management Differences
Sprain
- Early movement
- Strength + balance
- Gradual return
Growth Plate Injury
- Initial protection
- Controlled loading
- Careful progression
The Role of Physiotherapy
At Wimbledon Physiotherapy, as a KidsBack2Sport Centre of Excellence, we:
- Differentiate injury types
- Identify when referral is needed
- Guide safe rehab
- Support return to sport
Final Thoughts
In children:
An ankle injury is not always “just a sprain”
Understanding the difference ensures:
- Safer recovery
- Faster return
- Reduced risk of complications
Concerned About Your Child’s Ankle Injury?
Book an assessment with our specialist children’s physiotherapy team today.
FAQs
Can X-rays miss growth plate injuries?
Yes especially Type I injuries.
Does every child need an MRI?
No only if symptoms persist or diagnosis is unclear.
Is growth affected long-term?
Rare but possible if significant injuries are missed.