back pain and foot pathology

AUTHOR: Marc Mitnick DPM

REVIEWED BY: Podiatric Medical Review Board

You are probably wondering why I am writing an article on back pain when this site is devoted to foot pain. The simple answer is that in many instances pain in your back may actually be the result of a problem occurring in the feet, specifically, the way the feet function during the gait cycle.

For those of you old enough to remember the old song about the foot bone is connected to the ankle bone; the ankle bone is connected to the leg bone..... and so on, the point of the song is that there is a connection between the feet all the way up to the lower back. This is known as the kinetic chain. Just as some back issues can end up causing pain in the feet, problems in the feet can end up causing back pain.

Over the years, I have placed numerous people in orthotics for a variety of foot problems, where the orthotic is intended to modify the patient's gait. In a lot of these situations, when the patient comes back for an orthotic check-up, they will proceed to tell me that not only is their foot feeling better but they have also noticed that their back issues have also improved.

HOW DOES FOOT FUNCTION AFFECT THE LOWER BACK?

On average, a person will walk anywhere from 2500 to upwards of 15000 steps per day. If there is a malfunction occurring in either or both feet, over time, this will cause a stress point somewhere along the kinetic chain. A term that is used quite frequently these days in musculo-skeletal pain is "repetitive stress" where the accumulation of small stress leads to a major pain, in this case, the lower back.

This repetitive stress which plays out day after day, week after week, year after year, may eventually lead to the breakdown of joints leading to arthritis and a breakdown of muscle leading muscle fatigue and ligament issues.

Generally speaking there are two instances where a foot imbalance may lead to back pain. Prolonged periods of standing and after walking a fair distance. This pain may occur as a result of abnormal foot function even though there is no actual foot pain. The point to be taken from this article is the fact that if you are suffering from chronic back pain and medical treatment directed at the back has not helped, then the next logical step would be to look at your feet as the source of your back pain.

I have read that something like 70 percent of all lower back surgeries eventually either never relieve the back pain or the back pain returns in a very short period of time. In fact there is even a procedure code used in medical billing for "failed back surgery".

Although I have no hard statistics to back this up, possibly the high rate of surgical failure is due to the fact that foot biomechanical issues that may have exacerbated the back problem were never properly addressed, so no matter how spectacular a surgical procedure on the back may be performed, it may be doomed to failure.

If there has never been a direct trauma to the lower back and your complaints of lower back pain seem to come out of nowhere, this would be a good indication to at least look at your feet as a source of your pain.

One of the purposes of the foot is to absorb shock when the heel comes down. This generally occurs in the subtalar joint which is the joint just below the ankle joint. Normal heel strike in most individuals is on the posterior lateral side of the heel, so that is where you will notice excess heel wear on your shoes.

If there is limited motion or no motion in the subtalar joint shock will not be adequately absorbed by the foot and this excess shock is sent up the leg, all the way up to the lower back. A lot of this shock may be absorbed in part by the ankle, knee and hip joints, but if any of the excess shock reaches the lower back, over time it may cause issues within the back itself.

So, lack of shock absorption is one issue that may adversely affect the lower back. The next is a limb length discrepancy where one leg is shorter than the other. Most people exhibit some degree of limb length discrepancy but in very general terms, any discrepancy less than one half inch is not considered pathological.

In situations where there is an abnormal discrepancy this may impact the lower back. A flexion deformity of the lower back, lets say from poor posture like not sitting up straight, causes the back of the vertebrae to open up and causes a compression of the front of the vertebrae. Stated simply, the vertebrae do not line up properly.

Add to that the situation where there is a limb length discrepancy. The difference in the limb length than cause further exacerbation of the poor alignment on one side of the vertebrae. It can also create a torquing motion in the spine which then causes the muscles on one side of the back to work harder than the other side and that obviously can lead to muscle pain.

There are a few conditions within the foot itself that will alter one's gait just enough to create repetitive stress which in most cases will lead to a foot problem, but in a certain percentage of cases will also lead to back pain.

FOOT PROBLEMS THAT MAY AFFECT GAIT

Some of these include a hallux limitus, which is the inability of the big toe joint to allow the big toe to bend upwards. It is the bending upwards of the big toe that allows us to propel our foot off the ground and move it forward to the next step. If there is a "hitch" in the ability to propel the foot forward, this may manifest itself as lower back pain.

Arthritic changes in the mid portion of the foot is another problematic area. In the mid-stance part of the gait cycle where the foot is supposed to be flat on the ground, any problems in the mid-foot may cause another "hitch" in an otherwise smooth gait cycle and thus lead to pain in the lower back.

Lastly, lack of ankle dorsiflexion which is the foot bending upward relative to the leg at the end point of mid-stance will also have the potential to cause back issues.

Usually, we as foot specialists will see a patient for a specific foot complaint, possibly one of the aforementioned foot problems. In an effort to address the foot issue, we may prescribe an orthotic. Sometimes it can be something as simple as an arch support purchased in a store. More often than not, however, a custom device has to be prescribed in order to accommodate the foot abnormality.

If the orthotic is effective for the foot problem than it would stand to reason that the same orthotic will have a positive effect on the lower back. It is not to say that an orthotic will cure a lower back problem, but if it can be determined that part of the back pain is coming from a foot malfunction, than an orthotic will be very helpful.

As I mentioned earlier, if your back pain is most noticeable after long periods of standing or if it seems to worsen after you have been doing much walking, then it is important to have your feet evaluated as well as your gait cycle.

see related article....orthotics
see related article....gait cycle
see related article....hallux limitus
see related article....ankle pain
see related article....limb length discrepancy

Frequently Asked Questions

How can foot problems cause lower back pain?

Foot issues can create abnormal stresses that travel up the kinetic chain to the lower back. When the feet do not function properly during walking, the resulting imbalance can overload joints and muscles higher up the body.

What is the kinetic chain and why does it matter?

The kinetic chain describes how the feet, ankles, knees, hips, and back are all mechanically connected. A problem in one area—especially the feet—can affect the alignment and function of the entire chain.

Can abnormal gait lead to back pain even without foot pain?

Yes — gait abnormalities often cause back pain long before the feet ever hurt. Repetitive stress from poor foot mechanics during standing or walking can gradually strain the lower back.

What foot conditions commonly contribute to back pain?

Hallux limitus, midfoot arthritis, and limited ankle dorsiflexion can all disrupt normal gait. These “hitches” in the walking cycle may create enough repetitive stress to trigger lower back discomfort.

Can orthotics help reduce back pain?

Orthotics often improve back symptoms by correcting faulty foot mechanics. When the underlying foot imbalance is addressed, many patients notice both their foot pain and back pain improve.

REFERENCES

SPINE-health

Illinois Bone and Joint Institute

University of Rochester Medical Center