Iselin’s disease is a relatively uncommon but important orthopedic condition that affects children and adolescents during periods of rapid growth. Characterized by pain and inflammation along the outer edge of the foot, the condition can significantly impact mobility, athletic participation, and overall quality of life. Although the name may sound alarming, Iselin’s disease is a temporary, self?limiting condition that resolves once skeletal maturity is reached. Understanding its causes, symptoms, diagnosis, and treatment is essential for parents, clinicians, and young athletes who may encounter this condition.
Anatomical Background
To understand Iselin’s disease, it is helpful to first examine the anatomy involved. The condition affects the apophysis, or growth plate, located at the base of the fifth metatarsal, the long bone on the outer side of the foot that connects to the little toe. This bony prominence, known as the styloid process, serves as the attachment point for the peroneus brevis tendon, a muscle responsible for everting the foot. In growing children, this apophysis is made of cartilage and is therefore more vulnerable to stress and traction forces than mature bone.
According to clinical descriptions, Iselin’s disease occurs when this growth plate becomes irritated or inflamed due to repetitive stress or overuse. Because the apophysis is an area of relative weakness during growth spurts, it is particularly susceptible to injury in active children.
Causes and Risk Factors
The exact cause of Iselin’s disease is not fully understood, but the prevailing theory is that it results from repetitive traction of the peroneus brevis tendon on the developing growth plate. Activities that involve running, jumping, cutting, or rapid directional changes—common in sports such as soccer, basketball, gymnastics, and dance—place repeated stress on the lateral foot.
Multiple sources emphasize that the condition most often affects children between 8 and 14 years old, with a peak incidence during growth spurts when the apophysis is most active and vulnerable. Young athletes are particularly at risk due to the combination of skeletal immaturity and high levels of physical activity.
Other contributing factors may include:
- Poorly fitting footwear
- Sudden increases in training intensity
- Foot biomechanics such as high arches or supination
- Direct trauma to the outer foot
Although the condition is sometimes referred to as a “disease,” it is not infectious or systemic; rather, it is a localized overuse injury.
Clinical Presentation
The hallmark symptom of Iselin’s disease is pain along the outer border of the foot, specifically at the base of the fifth metatarsal. The pain typically worsens with physical activity and improves with rest. Children may describe the discomfort as aching, sharp, or throbbing.
Common signs and symptoms include:
- Localized swelling or tenderness over the styloid process
- Pain during running, jumping, or pushing off the foot
- Difficulty wearing tight shoes due to irritation of the bony prominence
- A limp or altered gait in more severe cases
Some children may also experience redness or warmth over the affected area, though these symptoms are less common.
Because the symptoms can mimic other conditions—such as fractures, tendon injuries, or infections—accurate diagnosis is essential.
Diagnosis
Diagnosis of Iselin’s disease is primarily clinical, based on history and physical examination. A clinician will typically palpate the outer foot to identify tenderness over the apophysis and assess pain during resisted foot eversion.
Imaging may be used to confirm the diagnosis or rule out other conditions. X?rays can show fragmentation or irregularity of the apophysis, although these findings can also be normal variants in growing children. Therefore, radiographic interpretation must be made in the context of clinical symptoms.
Advanced imaging such as MRI is rarely needed but may be used in atypical or severe cases.
Treatment and Management
Fortunately, Iselin’s disease is a self?limiting condition, meaning it resolves naturally once the growth plate closes. Treatment focuses on symptom relief and reducing stress on the affected area.
Conservative Management
Most cases respond well to conservative measures, including:
- Rest and activity modification: Reducing or temporarily stopping high?impact activities allows the apophysis to heal.
- Ice therapy: Applying ice helps reduce inflammation and pain.
- Non?steroidal anti?inflammatory drugs (NSAIDs): These may be used for short?term pain relief, though medical guidance is recommended.
- Footwear adjustments: Supportive shoes or orthotics can reduce traction on the peroneus brevis tendon.
- Stretching and strengthening: Physical therapy may focus on calf and peroneal muscle flexibility to reduce tension on the growth plate.
According to pediatric orthopedic sources, symptoms typically improve within several weeks of appropriate management.
Immobilization
In more severe or persistent cases, short?term immobilization using a walking boot or cast may be recommended to fully offload the foot and allow healing.
Return to Activity
Children can gradually return to sports once they are pain?free during daily activities and physical examination shows no tenderness. Because the condition cannot recur after skeletal maturity, long?term prognosis is excellent.
Differential Diagnosis
Because lateral foot pain in children can have multiple causes, clinicians must distinguish Iselin’s disease from:
- Avulsion fractures of the fifth metatarsal
- Jones fractures
- Peroneal tendonitis
- Stress fractures
- Infection or inflammatory conditions
Accurate diagnosis prevents unnecessary immobilization or prolonged activity restriction.
Impact on Mobility and Quality of Life
Although temporary, Iselin’s disease can significantly affect a child’s participation in sports and daily activities. Young athletes may struggle with reduced performance, missed practices, or frustration due to pain. Early recognition and appropriate management help minimize disruption and support a safe return to activity.
Sources emphasize that understanding the condition is crucial for parents and coaches, as pushing through pain can worsen symptoms and prolong recovery .
Iselin’s disease is a growth?related overuse injury affecting the apophysis of the fifth metatarsal in children and adolescents. While it can cause significant discomfort and limit physical activity, the condition is benign, temporary, and highly responsive to conservative treatment. Awareness of its symptoms, causes, and management strategies allows for early intervention and helps young athletes maintain healthy participation in sports. With proper care, children typically recover fully and experience no long?term complications once skeletal maturity is reached.