Pain on the outside of the foot, commonly known as lateral column pain in the medical community, is a fairly common occurrence. This is usually a result of some sort of twisting injury to the foot or an injury such as a sprained ankle. It can also be the result, in some cases, of certain shoe styles.
What exactly is the lateral column of the foot? Look at the diagram and note the long green arrows. That is the part of the foot that is known as the lateral column of the foot.
Lateral column pain can range from a dull pain that is only noticeable doing certain tasks, all the way up to constant pain that is present regardless of one's activity. Accordingly, the affected area may appear perfectly normal, all the way to severe swelling, redness and bruising.
CAUSES OF LATERAL COLUMN PAIN
Without a history of trauma but with an onset of lateral column pain, the first thing that needs to be examined is the shoe(s) that you are wearing.
Again, looking at the diagram, you can see that the fifth metatarsal has a flare to it at the base. In some people this is much more pronounced than in others.
Fifth metatarsal base pain- for those with a very wide flare, a shoe that is too narrow in that part of the foot will put excessive pressure on what is known as the fifth metatarsal base and in many cases will lead to pain.
Peroneal tendonitis- not only can the base of the fifth metatarsal be aggravated but the peroneal tendons can also be irritated. The peroneus longus tendon and the peroneal brevis tendon both originate on the outside of the lower leg. The tendon of each muscle travels down the outside of the ankle and then across the outside of the foot. The peroneus brevis tendon attaches into the top of the fifth metatarsal base. The peroneus longus tendon follows a more precarious course. At the level between the fifth metatarsal base and the cuboid bone (just behind the fifth metatarsal base), the peroneus longus tendon cuts under the foot and travels all the way to the first metatarsal bone.
The point here is that both tendons are prone to excessive pressure that may be brought about by shoe styles that are too narrow in this part of the foot. In addition to shoes that are too narrow, shoes that are too flimsy and not very supportive, such as flip flops and some sandals will also create excessive pressure on the bottom of the foot in this area and also cause problems.
Os peroneum- poor foot wear can also be the precipitating factor in a painful os peroneum. The os peroneum is an accessory (extra) bone that some but not all people exhibit. Approximately, a quarter of the population exhibit this bone. This is a small bone that is located within the tendon of the peroneus longus tendon at the level of the cuboid. Again, because this small bone happens to be on the outside of the foot, any shoe that is too narrow or not very supportive, will have a tendency to irritate this bone.
So for most people, just changing the type of shoes that you wear may go a long way in reducing lateral column pain. With no history of actual trauma to the foot, this would be the first thing to do in an effort to alleviate your foot pain.
In instances of trauma to the foot or ankle, the stakes become a little higher. In trauma, there is usually more damage to the outside of the foot then would be found in situations where the shoes are too narrow.
Fracture. The bones that are most commonly affected would include an anterior process fracture of the calcaneus. The calcaneus is the heel bone and in cases of twisting type injuries, the front part of the heel bone may chip off. This diagnosis may be made on the basis of an x-ray, CT scan or an MRI.
The fifth metatarsal base is also a very common site for a fracture particularly in lateral ankle sprains. Again, because of the way the bone protrudes, excessive pressure from trauma will cause the base to fracture. The problem here is that the base of the fifth metatarsal bone is poorly vascularized, relative to the rest of the bone. This can be a cause for concern because depending on how poor the circulation is and how bad the fracture may be, there is a good chance the fracture will not heal strictly by immobilization. In many cases this can supplemented with a bone stimulator. In some cases surgery with placement of a screw is necessary to allow the fracture site to heal.
The bone in front of the calcaneus, otherwise known as the cuboid may also fracture. Most cuboid fractures as the result of a twisting foot injury or ankle sprain tend to be very small and may not be picked up on an x-ray. A CT scan or MRI may be a better alternative.
Subluxed cuboid- another problem involving the cuboid bone in cases of trauma is what is known as cuboid syndrome. This is actually a subluxation (dislocation) of the cuboid bone. Many times the "movement" is so small that it is missed on all diagnostic tests and the diagnosis is usually made on clinical presentation. This is a diagnosis that most non-foot specialists will miss.
Tendon tear- lastly, in cases of trauma, we need to be concerned about a tear to either the peroneus long tendon or peroneus brevis tendon. In a tear to the peroneus longus tendon we also need to be concerned about the os peroneum bone. This bone may also fracture or depending on the type of tear to the peroneus longus tendon, may migrate (move) and thus become a constant source of pain. Tendon tears are best identified with an MRI.
TREATMENT OF LATERAL COLUMN PAIN
Treatment for most of these traumatic conditions of lateral column pain may be treated with:
oral anti-inflammatory medication
eliminating the offending shoe is mandatory
in some recalcitrant cases, surgery may be indicated.
PLANTAR FASCIITIS SURGERY AND LATERAL COLUMN PAIN
In any discussion of lateral column pain in the foot a discussion of this type of pain as a result of surgery for plantar fasciitis should be mentioned. Some of you may have come to this page because you had surgery for a heel spur or plantar fasciitis and now you are experiencing pain on the outside of the foot.
One of the potential complications of heel surgery is an over aggressive incision into the plantar fascial ligament in an effort to alleviate the heel pain. When too much of the ligament is incised, it basically destabilizes the rear and outside portion of the foot and can cause lateral column pain.
If you have had heel surgery and are now experiencing lateral column pain it is important to bring it to the attention of your surgeon. A combination of physical therapy and orthotic therapy early on, is usually sufficient in alleviating this complication.