I have many patients who seek treatment for a vague pain or discomfort along the outside (lateral aspect) of their foot. During the discussion of their history of the pain or discomfort, the patient will report an ankle sprain injury that occurred the previous 3-5 years. The patients will also report the acute ankle sprain healed without incident. Ankle sprains occur when you roll over on the outside (lateral) of the ankle and tear the ligaments on the outside of the ankle. Sometimes this injury can cause bones to fracture.
Acute ankle sprains are one the most common lower extremity injuries that people seek treatment for in US and Canadian emergency departments.
The treatment for your acute ankle sprain in the ER may include x-rays, use of an Aircast™, crutches, activity modification, icing, application of a tensor bandage, referral to a physical therapist, or surgery to realign ankle bone fractures. Balance exercises are usually prescribed to reestablish sensory receptors around the ankle that send balance information to balance centres in the ear. People who have chronic ankle instability cannot easily balance themselves standing on one foot with their eyes open. If they close their eyes it is even worse. Surprisingly, many people will not seek any health professional treatment with their ankle sprain.
What is the link between pain on the outside (lateral aspect) of the foot and the old ankle sprain?
One of the least recognized outcomes of ankle sprain is an injury to the ligaments around the cuboid bone on the lateral aspect of the midfoot. A lateral ankle sprain can cause a rotation of the cuboid bone due a protective muscle reflex of the peroneus longus tendon. During an ankle sprain the peroneus longus muscle may try to prevent your ankle from rolling over. The peroneus longus tendon is a muscle that helps to stabilize the lateral aspect of the foot. The peroneus longus tendon courses from the lateral side of the foot to underneath the cuboid and crosses to the other side of the foot.
Long after your ankle has healed the cuboid can still be slightly out of alignment in relation to the adjacent bones. The nerves around the cuboid joints can be irritated because it is misaligned. A cuboid subluxation may cause lateral foot pain and weakness as the heel lifts off the ground while walking. The pain often radiates from outside to inside underneath the foot following the course of the peroneous longus tendon, the front of the ankle joint or distally along the fourth ray.
An examination will elicit pain when the cuboid is pushed upwards from underneath. The range of motion of the cuboid is minimal when compared to the cuboid on the other foot.
The treatment to realign a subluxed cuboid consists of a series of osteopathic manual foot manipulations. These manipulations will restore the cuboid joint range of motion as well as the joints behind and in front of the cuboid. There are a number of medical conditions where manipulations are not indicated. The medical conditions include: inflammatory arthritis, gout, nerve or blood vessel abnormalities, bone tumors, osteoporosis and bone fractures.
After the manipulation has been performed the area should be iced. Felt padding is usually applied underneath the cuboid along with arch taping to stabilize the foot. A couple of follow manipulations may be required. Balance exercises and muscle strengthening may be recommended.
An old ankle injury could be the cause of your current vague foot pain.