Approach to the Exam of the Ankle and Foot

The painful conditions of the ankle and foot are very common presentations and most commonly caused by trauma or injury related to sport activities. It is important to be familiar with some basic physical exam maneuvers necessary to confirm the presence of a lesion and to assess its severity.

Foot and Ankle Exam

Introduction

The physical exam is of crucial importance for the clinical evaluation of painful conditions of the foot and ankle. These disorders are very common in the outpatient setting, both among professional athletes and recreational exercisers. It is important to be familiar with some basic maneuvers and physical signs necessary to assess the presence and the severity of lesions in the osteo-ligamentous structures of the foot.

Foot and Ankle Anatomy

Important anatomical structures that one must be familiar with while examining the painful ankle and foot, are the following:

  1. Lateral ligaments of the ankle:
    1. Anterior Talo-Fibular Ligament (ATFL): running anteriorly from the lateral malleolus to the talusPosterior Talo
    2. Fibular Ligament (PTFL): running posteriorly from the lateral malleolus to the posterior aspect of the talus
    3. Calcaneo-Fibular ligament (CFL): running from the lateral malleolus to the lateral aspect of the calcaneous, in the middle between the ATFL and the PTFL
  2. Achilles tendon
  3. The talar dome: upper portion of the talus, where the articular cartilage for the tibiotalar joint is located
  4. Metatarsal bones
  5. Interdigital nerves

Anatomy of the ankle. Image credit

Lateral Ankle Sprain

Foot and Ankle Exam

One of the most common causes of foot pain is a lateral ankle sprain. In the mildest presentations, the only structures to be injured are the lateral ankle ligaments, usually in the number or one or two. However, if the damage is more severe, we can observe lesions of all the lateral ligaments plus other structures like the talar dome, the base of 5th metatarsal and the tibio-fibular syndesmosis.

The approach is to check for the integrity of the lateral ligaments first and if all the three ligaments are injured, then we will check the other structures.

Inspection and Palpation

First, have the patient lying down supine with the knee bent on the affected side.

Then, observe the lateral aspect of the foot and ankle for hematomas or bruises.

Then, locate the three lateral ligaments and palpate along their course for crepitus and tenderness.

Lateral ankle inspection and palpation. Image credit

ATFL rupture: Anterior Drawer Sign

This is a provocative test done to check for the integrity of the ATFL. One hand holds the leg down, while the other hand pulls the foot upwards and anteriorly. It is important to compare one side with the other. The presence of tenderness or laxity on one side only indicates an ATFL rupture.

Anterior drawer sign.

CFL rupture: Forced Inversion

This is a provocative test done to check for the integrity of the CFL. Forcefully invert the foot while keeping the leg still with the other hand. Make sure to compare side to side. Again, tenderness or laxity on one side indicate a CFL lesion.

Osteochondral Defect of Talar Dome

To assess for an osteochondral defect we must first locate the talar dome and then palpate to elicit tenderness.

To locate the talar dome we must identify the lateral malleolus and then move anteriorly from it, up to the anterior recess. From here we can move medially and anteriorly along the joint line. The talar dome will be right beneath this point.

Any tenderness elicited by palpating at the level of the anterior joint line is indicative of an osteochondral defect.

5th Metatarsal Base Fracture

To asses for a fracture at the level of the 5th metatarsal base, palpate along the lateral margin of the foot to elicit pain and to feel for any bone defects or irregularities.

Tibio-Fibular Syndesmosis Damage

If there is a high grade ankle sprain with associated damage of the talar dome and/or a 5th metatarsal fracture, we must rule out an injury of the syndesmosis. To assess for a syndesmosis damage, we can use two provocative tests: the external rotation test and the squeeze test.

External rotation test

Gently rotate the foot externally while holding the leg still. Any tenderness would be positive for a syndesmosis damage.

External rotation of the foot.

Squeeze test

Squeeze the tibia and the fibula together to elicit tenderness. If present, this indicates a syndesmosis damage.

Squeezing of the tibia and fibula.

Achilles Tendon Pain / Achilles Tendonopathy

Foot and Ankle Exam

Achilles tendinopathy is one of the most common foot pathologies. It can affect both athletes and recreational exercisers, being reported in inactive people as well. Clinically it manifests with foot pain on exertion associated with swellings, nodules and tenderness on palpation of the tendon.

Achilles Tendon Palpation

To assess for Achilles tendinopathy, palpate the entire length of the tendon moving downwards. Identify any fusiform swellings, defects or tenderness.

Palpate the entire length of the Achilles.

Also, palpate the sides of the tendon at the level of the heel to check for the presence of a bursa, or for any bony spurs.

 

Once an abnormality is identified, if it moves upon flexion and extension of the foot, then we can conclude that it is part of the Achilles tendon.

Palpate the heel and confirm that a lesion is part of the Achilles.

Achilles Tendon Rupture

Commonly presenting with acute onset pain at the heel during physical activities that determine a sudden stretching of the tendon, followed by loss of function of the affected lower extremity.

Sometimes it is possible to hear a popping sound when the rupture occurs.

Achilles tendon rupture. Credit.

Squeeze Test or Thompson’s Test

To confirm a suspected Achilles tendon rupture, have the patient lying prone and then squeeze the calf while observing the foot. If there is plantar flexion of the foot, this means that the tendon is intact. Otherwise, a reduced or absent plantar flexion, when compared with the other side, is indicative of a tendon rupture.

Achilles Rupture: other signs

Always with the patient lying prone, hyperdorsiflex both feet at the same time to feel for a buoyant endpoint, indicative of a tendon rupture.

Hyperdorsiflex both feet to feel for a buoyant endpoint.

Also, observe how the foot falls off the bed. A normal foot would be slightly raised and plantar flexed. A foot that is dropping in dorsiflexion would be a sign of Achilles tendon rupture.

Observe how the foot falls off the bed.

Causes of Forefoot Pain

Foot and Ankle Exam

Interdigital (Morton’s) Neuroma

Perineural fibrosis that develops around one of the interdigital nerves, as a consequence of chronic trauma. More common in middle-aged women, it classically presents as a paroxysmal stabbing pain originating from a web space, usually the 2nd or 3rd web space.

Mulder's Click

It is a provocative test that consists in compressing the metatarsal heads. If the pain is reproduced and/or a click is felt upon palpation, then the test is considered positive for the presence of a Morton’s neuroma.

2nd Metatarsal Stress Fracture

The most common site for a stress fracture in the forefoot is the 2nd metatarsal, given that most of the body’s weight is transferred on this particular bone during every given gait cycle.

To uncover a stress fracture on physical exam, carefully palpate the 2nd metatarsal in all its length. Tenderness upon palpation would be a sign that a fracture is present. 

Compress the metatarsal heads. Image credit

Plantar Fasciitis

Foot and Ankle Exam

This represents the most common cause of heel pain.

The pain is usually described as sharp and tends to be more intense with the first steps after long periods without weigh bearing, such as after a night sleep.

There are two ways of confirming the suspicion of plantar fasciitis on physical exam.

First, we can elicit pain upon palpation of the origin of the plantar fascia on the plantar-medial calcaneal tubercle.

Also, we can notice tenderness on forced dorsiflexion of the first toe, a maneuver called “the windlass mechanism.”

The windlass mechanism.

Hallux Valgus or Bunion

Foot and Ankle Exam

A common cause of both pain and deformity of the forefoot is the hallux valgus or bunion. It consists of a valgus deformity of the first MTP joint. The etiology is not completely understood even though it seems to be related to wearing tight shoes. Also, it is more commonly diagnosed in women.

Physical exam findings

It is usually possible to elicit a characteristic crepitus of the first MTP joint upon palpation.

Also, there is usually evidence of restricted ROM of the first MTP joint.

Palpation of the 1st MTP joint.