Etiology — what causes it
Progressive degeneration of the posterior tibial tendon, leading to medial longitudinal arch collapse over time. Risk factors include obesity, female sex, age over 40, hypertension, diabetes, and inflammatory arthropathies.
Epidemiology — who gets it
Most common cause of adult acquired flat foot, especially in women over 40. Insidious onset; often progressive if untreated.
Clinical signs
Medial ankle and arch pain, swelling along the tendon course, weakness on resisted inversion, single-heel-raise test (inability to perform or asymmetric inversion of the heel), 'too many toes' sign from behind. Imaging confirms tendinopathy or tear.
Symptoms
Medial ankle and arch pain progressing over months. Difficulty walking on uneven ground, fatigue after standing, progressive arch collapse. Pain often migrates from medial to lateral as deformity progresses.
Best evidence for chiropractic treatment
Stage-based management (Johnson and Strom classification). Stage I–II — progressive loading of the posterior tib (heel raises with inversion bias), tibialis posterior strengthening, orthotic support, and bracing in selected cases. Stage III–IV with rigid deformity often requires surgical consultation.
Subtypes
- Stage I. Tendinopathy with normal alignment.
- Stage II. Flexible flat foot deformity.
- Stage III. Rigid flat foot deformity.
- Stage IV. Lateral ankle involvement.
When to seek emergency care
Some symptoms need urgent medical attention — not a chiropractic visit. Call 911 or go to the nearest emergency department for: progressive limb weakness, loss of bowel or bladder control, saddle anesthesia (numbness in the groin/inner thighs), severe unrelenting pain unrelieved by position, signs of fracture after significant trauma, chest pain, stroke-like symptoms (face drooping, arm weakness, speech changes), or any rapidly worsening or unusual symptom.
Bottom line
Early-stage PTTD responds to progressive loading and bracing. Late-stage rigid deformity often needs surgical consultation.