Health Matters: The mysterious midfoot pain
This is the story of Sue, a middle-aged, hardworking individual with a busy family and healthy social life. Sue had recently turned 50, a traumatic age, and it wasn’t going well. She recently learned she had high blood pressure and was pre-diabetic, with dire warnings from her primary care provider that she had to change something, be it diet or exercise levels. Then, to top it off, the foot pain started.
This wasn’t one of her work-induced aches and pains. This was significant, sharp, and could even take her breath away. Initially, increasing activities seemed to be the key to its development, with sharp or shooting pains originating from the top of her foot. Certain shoes were also clearly problematic, with the pressure of the shoe leading reliably to a significant increase in pain levels. Sue’s response was to alter her shoe gear and reduce her activities. Turns out, Sue was experiencing a common condition that many have suffered from (although for varied reasons).
The anatomy of the foot, with its 28 bones, hundreds of ligaments, ubiquitous nerves and arteries, tendons and muscles, is amazingly complex. Then, add in the functions of the foot, carrying us from point A to B, allowing us to jump, run, and perform all manner of movements and actions, and the complexity increases exponentially. The foot is a marvel of biology, but the biomechanical functions allowing it to fulfill these tasks remain only partially understood.
Our protagonist had no history of an injury or misstep, no trauma to the area, which might have led to this discomfort, and her activity levels hadn’t changed noticeably. Yet, the pain from the top of her foot was becoming more intense and lasting longer, symptomatic throughout the day. Changing shoes initially was beneficial, but even that became ineffective. On the advice of a co-worker, she purchased an arch support, standing on a pressure plate display at a big box store. The analysis from the system looked impressive but the supports were of no benefit, providing no change in her discomfort.
Eventually Sue was forced to make an appointment with her primary care office where they diagnosed arthritis, although she wondered why only here. They prescribed an anti-inflammatory. Indeed, regular use of naproxen provided some relief and made life more tolerable. But as soon as she stopped the medication, the pain came back.
It is at this juncture that she presented to my office. A careful and detailed analysis of Sue’s foot, ankle, and lower leg revealed the presence of a frequent complaint, a painful joint at the “top” of the foot, in front of the ankle. The architecture of the foot is such that in many of us, for varied reasons, great force is experienced by the bones in this area. When these forces, generated with every step, are excessive, problems usually occur.
The pressure exerted by the body on this part can be tremendous, depending on one’s biomechanics. Many structures will become painful if subjected to excessive physical forces. When inflammation develops, pain ensues, as does swelling, sometimes even warmth. The capsule that covers the joint where the 2nd metatarsal meets the bones of the middle section of the foot is the most common site for these symptoms.
Numerous reasons have been found for chronic pain and swelling from this part. People with a high arched foot commonly have problems here. This foot type tends to experience exaggerated compressive forces in the middle of the arch. Alternatively, a common variation is a foot with a long 2nd metatarsal, putting more pressure on the base of the bone when the heel lifts up (as in gait). Once again, greater forces mean more risk of inflammation and pain developing at some point.
As you may have gathered, this problem can manifest in all sorts of ways. With time, the compressive forces may lead to bone spur production. These, in turn, can poke the soft tissues in the area causing pain. An important nerve runs over this region and that structure may become symptomatic, producing a burning or shooting sensation. Degenerative changes from the mechanical forces are common, leading to cartilage loss and deep bone changes. The pain may lead to overuse of some other tendon, resulting in a completely new area becoming symptomatic.
Many Americans suffer from a tight Achilles tendon. This is the largest tendon in the body, with the most force running through it. When tight, it alters the function, the mechanics, of many joints, muscles, ligaments and more. With excessive pull of the Achilles on the heel, leverage on the joint formed by the 2nd metatarsal and the nearer bone is increased. With sufficient stress, inflammation develops and pain is the result.
Treatments are many and varied. As Sue discovered, because the pain is inflammatory in nature, a non-steroidal anti-inflammatory drug (ibuprofen, naproxen, etc) or an actual steroid (injected or by mouth) will help. And if the problem was caused by a single traumatic event, these pharmaceuticals may reduce the pain until the body can heal up the damage. Thus, upon discontinuing the drug, the discomfort doesn’t return. But when the root of the problem is your foot and leg biomechanics, the relief is purely temporary.
A very different approach is the precise, controlled alteration and improvement of someone’s biomechanics (the specifics of the structure, function and motion of the human body). Although technically difficult, and too often poorly done, the most practical way to do that is with the use of custom foot supports. Technically, these are termed foot orthoses, but generally just called “orthotics.” Many have a negative experience because of the poor fit or function of the supports they have tried. When improperly prescribed, they can cause discomfort. But the actual production of a pair of foot orthotics, i.e. the analysis, the casting, the fabrication, needs to be a multi-faceted process. There are hundreds of factors that SHOULD BE considered. Expertise equals excellence when it comes to the device’s success.
For being such a common problem, this condition is poorly understood by your average family doc. Or physicians will treat the inflammation, which is simply a band-aid, ineffective since it isn’t addressing the root of the pathology. This should be a question of what biomechanical abnormality is resulting in this joint being stressed. In this way, we are able to treat the cause rather than the symptom. As a generalization, in medicine, this is a more lasting approach. And that sounds like a recipe for relief.
Editor’s note: Dr. Conway McLean is a physician practicing foot and ankle medicine in the Upper Peninsula. Dr. McLean’s practice, Superior Foot and Ankle Centers, has offices in Marquette and Escanaba, and now the Keweenaw following the recent addition of an office in L’Anse. McLean has lectured internationally, and written dozens of articles on wound care, surgery, and diabetic foot medicine. He is board certified in surgery, wound care, and lower extremity biomechanics.