March 2016

Adult Acquired Flatfoot Deformity Exam

Adult acquired flatfoot deformity is a one of the most common problems of the foot and ankle in the adult population. The deformity results in significant dysfunction of the foot and ankle causing pain, difficulty in ambulation, skin breakdown and shoe wear difficulties. Accurate recognition and diagnosis by clinical exam is important in determining the proper cause and treatment recommendations.  The following is the exam I use to determine the anatomical structures involved so a proper treatment can be recommended.

I usually start with the patient standing sockless and shoeless bilaterally.  Here you can see a fallen arch and check for forefoot abduction. Also check for associated deformities such as hallux valgus and lesser hammertoes.  Next get the patient to face away from you to observe the hindfoot.  Here we assess hindfoot valgus and can look for the “too many toes” sign.   Get the patient to perform a double heel rise and observe for any correction in hindfoot valgus.  Then get the patient to perform a single heel rise (SHR) on the affected side.  Usually patients with adult acquired flatfoot deformity (AAFD) stage II or greater have difficulty with SHR’s.

I then get the patient on the exam table with the feet hanging over the edge of the table.  I start medially and palpate along the posterior tibial tendon, spring ligament and medial arch.  Next I palpate laterally checking for subfibular impingement pain and sinus tarsi pain.

A key portion of the exam is to evaluate if the deformity is flexible or rigid.  I first try and reduce the hind foot valgus to neutral and then correct the forefoot abduction and forefoot varus.  If the deformity is stiff and not correctable then the patient is AAFD stage III or IV.  I also check for subtalar range of motion (ROM) and ankle ROM.  If there is a lot of pain with subtalar ROM then I suspect some significant subtalar arthrosis.  When checking ankle ROM, I also look for an equinus contracture.

Submitted by:
Justin L. Daigre, MD
Decatur Orthopaedic Clinic
Decatur, AL