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PATHOLOGIES

MIDFOOT AND HINDFOOT CONDITIONS

Flatfoot (Pes Planus)

What is it?

Flatfoot, or pes planus, is a condition where the arch of the foot collapses, causing the entire sole to come into contact with the ground. It can occur in one or both feet, and may be flexible (arch appears when non-weight bearing) or rigid (arch absent in all positions).

Types

Flexible flatfoot: Most common, especially in children. The arch is visible when the foot is off the ground. It is correctable on examination.
Rigid flatfoot: Less common and usually more severe. The arch is absent both in standing and sitting positions. It is not correctable on examination.
Acquired adult flatfoot: Often due to dysfunction of the posterior tibial tendon, which supports the arch.

CAUSES

Congenital (present from birth)
Posterior tibial tendon dysfunction (PTTD) – often in adults
Ligament laxity or hypermobility (e.g., in Ehlers-Danlos syndrome)
Arthritis or trauma
Obesity or diabetes (can increase risk of adult-acquired flatfoot)

SYMPTOMS

Pain along the inner ankle or arch
Swelling around the inside of the l foot
Fatigue or aching in the feet and legs, especially after activity
Difficulty fitting into shoes
In more advanced cases: outward rolling of the ankle (hindfoot valgus), and eventual arthritis of foot joints

DIAGNOSIS

Clinical examination: Arch collapse, outward heeltilt, difficulty performing heel raises
Imaging:
- X-rays to assess bone alignment
- MRI or ultrasound may be used if tendon damage is suspected

TREATMENT OPTIONS

Non-Surgical

Supportive footwear with arch support
Custom orthotics or insoles
Physiotherapy to strengthen the posterior tibial tendon and improve foot mechanics
Activity modification and weight management
Anti-inflammatories for pain relief

Surgical (for progressive or severe cases)

Tendon reconstruction or transfer (e.g., FDL tendon for PTTD)
Osteotomies (realigning foot bones)
Arthrodesis (joint fusion in severe deformities or arthritis)

PROGNOSIS

Flexible flatfoot is often well managed with conservative care.
Adult-acquired flatfoot may progress if untreated but can be significantly improved with timely intervention.