ESCANABA — There is an abundance of unexplained medical conditions in the world, although our understanding has advanced tremendously. There is much we don’t know about the human body and don’t let anyone pretend otherwise. How about an explanation for “Stiff Person Syndrome” or Morgellon’s with the strange skin fibers? We don’t even understand something as common as migraine headaches. Schizophrenia and many disorders of the brain remain a mystery.

How about the one where an adolescent suddenly develops pain in the ball of the foot for no reason and without injury? In the disease under discussion today, the problem often resolves with time and no definitive diagnosis is made. Commonly, no treatment is provided, maybe the youngster decreases activity levels or changes their shoes. Unfortunately for many, it’s the accumulation of millions of steps that leads to symptoms.

The condition being discussed is an example of avascular necrosis (AVN), a term describing the loss of blood supply to some bone, which is especially common in the hip bone or knee cap but not infrequently seen in the foot. There this strange ailment occurs most commonly in the head of the second metatarsal bone. AVN causes the head of this bone to soften. Consequently, the stresses and pressures of ambulation and weight bearing lead to deformation of the surface of the metatarsal head.

The specific diagnostic term for avascular necrosis of the metatarsal head is Freiberg’s Infraction, but not ‘infarction.’ Yet, medically, that is exactly what occurs. The blood supply to this part of the bone is cut off, and part of the bone dies as a result. Indeed, ‘infarction’ is defined as the disruption in blood supply to a bone, which this is. Then why is this condition called an “Infraction?”

Dr. Freiberg, the physician who initially wrote about it, believed it to be a broken bone problem, aka a fracture. He subsequently labeled it as an infraction, as in a broken bone, a fracture. He had no inkling of the disruption of blood flow, which is correctly referred to as an infarction, not a fracture. But this condition isn’t called Freiberg’s Infarction since the old name was maintained despite its inaccuracy.

Because the diseased metatarsal head is soft and malleable, it becomes deformed from the forces exerted on these structures. This alteration in anatomy naturally alters joint function. The element of time comes into play since degenerative changes occur with sufficient time and enough steps. Chronic inflammatory pain generally will be experienced although, predictably, there are a multitude of variables in this discussion, some psychological, others biomechanical, and still others neurologic.

We know very little about this condition’s pathogenesis, the “how and why” of this shutting off of blood. When symptoms develop, the diagnosis is frequently missed since the radiographic signs are subtle, in no way obvious. A strange flattening of the head can be seen upon careful examination, with various patterns of deformation of the structure noted. With sufficient time, bony changes can also be seen in the toe bone involved with this joint.

Although sharp acute pain can certainly develop with this problem, more common is a dull aching pain from the center of the ball of the foot. A day of increased activities combined perhaps with the use of flexible-soled shoes can be enough to precipitate more obvious symptoms. On the topic of symptomatology, the elephant in the room is human variability, how pain is perceived, human biomechanical variations, etc., etc.

The latter item, a person’s biomechanics, is extremely pertinent to this discussion since we hypothesize that the forces exerted on this region of the foot may be part of its development. For example, something as common as a tighter Achilles tendon can result in excess repetitive trauma to the 2nd metatarsal. And this is an extremely common finding since most of our shoes have a positive heel. But make no mistake, numerous other anatomic and biomechanical variations can have this effect on this area of the foot.

Treatment options for someone with a Freiberg’s Infraction are many, including anything appropriate for an inflamed joint. A simple cortisone injection (i.e. a corticosteroid) can reduce acute symptoms but probably won’t have long term benefits since the cause of the inflammation is still there: the altered anatomy. The deformed metatarsal head impairs joint function. As long as the joint is getting used, i.e. the individual is standing and walking, the articulation will become reinflamed.

Although various surgical approaches have been utilized, the most successful tactic addresses their foot function and alignment, i.e. their biomechanics, with some kind of foot support, such as a custom foot orthotic. Also important is determining the presence of any muscle-tendon imbalance (aka stretching tight tendons and strengthening weak muscle groups). Unfortunately, our surgical options are limited. We don’t have a successful, lasting joint implant for this structure and we don’t have the ability to create a normally shaped 2nd metatarsal head (yet!).

Any type of chronic foot pain needs to be evaluated since lasting symptoms from a weight bearing structure will tend to alter gait. And, as a fairly accurate rule, if you disrupt the gait cycle for long enough, some other body part is going to become physically stressed. With time, inflammation develops resulting in discomfort. Eventually, degenerative changes of the cartilage and joint capsule materialize.

Perhaps your forefoot pain is due to Freiberg’s…..or maybe it’s something else. Make the effort to find out why you have symptoms from the area and what you can do. Living with chronic pain is bad for your physical, mental, and emotional health. Don’t suffer in silence, take an active role in your well-being by getting an accurate diagnosis and an effective treatment plan.

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Dr. Conway McLean is a physician practicing foot and ankle medicine in the Upper Peninsula, with offices in Escanaba, Marquette, and L’Anse. McLean has lectured internationally on wound care and surgery, being board certified in surgery, orthotic therapy and wound care. His articles on health and wellness appear in multiple local and national publications. Dr. McLean welcomes subject requests for future articles at drcmclean@outlook.com.