Health Matters: Bone spurs common in lower extremity

Conway McLean, DPM, Journal columnist

What follows is a common scenario: an individual experiences pain from the bottom of their heel. They mention it to their primary care provider who sends them for x-rays, an effective means of evaluating osseous tissue, i.e. bone. Examining the radiographs, the PCP finds a large spike of bone exactly where the patient is experiencing their pain. The obvious conclusion is the spur is causing the individual’s pain.

Bone is an interesting tissue, at least in part because of how it responds to stress. Obviously, bone must be produced for growth and repair. And many things can stimulate the process of bone growth, with the individual’s metabolism, nutrition, and blood flow, all being important factors, although this list is not inclusive. Unfortunately, bone production can be pathologic, meaning many situations can lead to abnormal bone growth.

Our patient has been told they have painful bone spurs, and naturally wonder what’s next? Does the spur need to be removed to obtain relief? For this patient, the healthcare provider injected a corticosteroid into the area (colloquially referred to as cortisone). Lo and behold, tremendous relief is obtained. But if it’s a bone problem, how could an anti-inflammatory provide relief?

This highlights the fact that not all bone spurs are painful. A spur on the bottom of the heel is rarely a weight-bearing structure, but instead is pointing outwards, towards the toes, hiding under the arch. This type of spur results from the pulling of the arch ligament on the heel bone. Bone reacts to stress, not by wearing out, but by overgrowing. Thus, this spur develops over time from a tight arch ligament (which is the structure actually generating the pain in our example). When this type of tissue is physically stressed, painful inflammation frequently results.

Another common site for spur formation is around a joint that is not moving or functioning correctly. When joint motion produces a jamming phenomenon of the two bones composing the joint, the physical stress leads to inflammation, and over time, bony overgrowth, aka spurring. The changes leading to inflammation will also commonly lead to pain as well. Maybe more important in the long run, degeneration of the cartilage lining the surface of the joint always degrades over time, a gradual, insidious process.

A frequent destination for spur formation is at the top of the big toe joint. The anatomy of this particular articulation is quite complex, and its motion found nowhere else in the human body. Alignment of the structures involved is critical to normal function, and when abnormal, physical stress is going to occur with gait. With time, this jamming leads to pain and spurs. These can become quite large and externally obvious. Naturally, shoe pressure is a common source of problems when these occur.

Certain disease processes will lead to bone spurs. Rheumatoid arthritis, an autoimmune disease, frequently leads to joint pain and swelling, along with enlargement and overgrowth of the bone around the joint. But bone loss is seen as well in this and other conditions making for significant deformity, a digit so affected becoming bent out of position, leaning off in some bizarre direction. Consequently, shoe fit can be treacherous.

Bone spurs in certain locations will understandably lead to symptoms, such as the top of the instep of the foot, where shoes are a consistent source of pressure. Extra bone is produced here usually due to the aforementioned jamming process, with a person’s foot shape and function having a tremendous influence over the severity of the pain. The pain experienced in this situation may be primarily from the jamming problem, with its associated inflammation, than from the presence of the actual spur.

Almost as common as spurs at the bottom of the heel bone are those behind it, back where the Achilles tendon attaches. These form also as a result of the pull of this large tendon, the largest in the body. Numerous factors go into the formation of these bony growths, occasionally quite impressive in their length, up inside the tendon. A tightened Achilles can increase the pull of the tendon on the bone which may stimulate the bone growth.

Diagnosing the presence of a bone spur is a simple matter. By knowing the normal anatomy, an obvious, localized bump at the top of the big toe joint is almost certainly one of these. X-rays are the obvious method of evaluation, with few complications and minimal expense. Yet, determining the biomechanical issue leading to the extra bone is another matter entirely and too often never determined.

A discussion of therapeutic measures is difficult since there are so many types, with an even greater number of causes. Often a bone spur produces no symptoms and demands no treatment. This may seem counterintuitive, as in the case of the (bottom) heel spur, where an often debilitating pain originates. But, as mentioned, the spur isn’t producing pain so only the plantar fascia, the arch ligament, requires treatment.

Accommodating a bump, meaning to make room for it, either via padding or alteration of a shoe or insole, is a frequent approach and can be successful on occasion. The inflammation that leads eventually to bone production can be reduced with an injection of anti-inflammatory medicine, although we currently have no medication which will dissolve bone.

Surgical removal can be a simple matter, depending once again on the location and type of spur, often performed through a tiny incision utilizing minimally invasive techniques. In contrast, when encased by the Achilles, removal means moving the tendon aside to get to the spur, demanding a more rigorous post-operative recovery. Operative care should be more about correcting the biomechanical issue with spur removal of lesser importance.

Spurs are common but need not be a source of difficulty or discomfort. A bump of bone can sometimes be a tumor, but that’s a wholly different discussion. The most productive approach when symptomatic will generally be utilized by a physician specializing in care of that structure or region of the body. But there are going to be a plethora of different methods and varying benefits. Be an educated health consumer. It’s the only body you have, so take care of it: find good people to help you care for it.

EDITORS NOTE: Dr. Conway McLean is a podiatric physician now practicing foot and ankle medicine in the Upper Peninsula, having assumed the practice of Dr. Ken Tabor. McLean has lectured internationally on surgery and wound care, and is board certified in both, with a sub-specialty in foot orthotic therapy. Dr. McLean welcomes questions, comments and suggestions at drcmclean@penmed.com.


Today's breaking news and more in your inbox

I'm interested in (please check all that apply)
Are you a paying subscriber to the newspaper *

Starting at $4.62/week.

Subscribe Today