When are flat feet normal?
- Normal in babies and toddlers, usually resolves by 6 years of age as the longitudinal arch develops.
- They persist in at least 10% of children, commonly are found with other features of hypermobility and are often familial (check parents feet !!).
- Management involves explanation, reassurance, and advice regarding appropriate supportive footwear (i.e supportive heel cup and mid foot support with fastened laces).
- Physiotherapists, orthotists and podiatrists may provide exercises and insoles if problems persist.
Photo: Flat feet in a healthy 4 year old - normal arches form when standing on tip toe - ie mobile flat feet.
When are flat feet not normal?
- Absent arch when child stands on tip toes (non-mobile flat feet).
- Asymmetrical changes (i.e. one foot fixed and flat).
- Evidence of pressure on the foot such as blistering / callosities.
- Swelling or stiffness of joints.
- Limping or persistent pain.
In teenagers with a fixed/painful flat foot, think of Tarsal Coalition (a condition where bones in the foot are joined together).
Inflammatory Arthritis can also cause a painful stiff flat foot. Radiographs can be normal. Referral is required for further investigation.
The indications for referral are:
- Joint stiffness or swelling.
- Absence of arch on tiptoe.
- Signs of pressure (eg blistering).
- Persistent pain.
- Limp or symptoms interfering with function (sport/play).
- Systemic features.
Referral is advised to rheumatology or orthopaedics pending your concerns and available referral pathways. Key conditions to consider include:
- Inflammatory Arthritis – joints are stiff, warm or swollen (often the midfoot).
- Tarsal Coalition – joints fixed and painful on walking and weight bearing.
Photo above : Stiff Flat Foot due to Inflammatory Arthritis (Juvenile Idiopathic Arthritis).
Photo below : Radiograph showing tarsal coalition with fusion of the calcaneum and navicular bones (arrowed)