My MRI says I have bone edema. How long will that take to heal?

Bone edema is the term used by doctors (radiologists) to describe swelling within bone.  Bone swelling is typically identified on MRI and is the result of either a direct injury to bone or load bearing that is greater than what can be sustained by the bone (stress injuries).  Bone edema can also be found secondary to an inflammatory injury of bone.  Inflammatory injuries include various forms of infection or arthritis. 

How does bone edema heal?  The first issue to consider when discussing bone edema is the primary cause for the bone edema.  For instance, if bone edema is secondary to an infection, the infection has to be treated for the bone edema to heal.  Or if the bone edema is due to a stress injury, the mechanical stress needs to be eliminated. 

Once the primary cause for bone edema is identified and eliminated, then we can look at the dynamics of bone healing in response to bone edema.  One classic tool that helps to determine the rate of bone healing is a classification scheme.  In many types of bone injuries/fractures we use classifications schemes to define characteristics of the injury such as depth of the injury, overall size of the injury, etc.  Classification schemes help to guide us with answers to our patient’s question such as how long will this take to heal.  But when we discuss bone edema, we have a problem.  To date, we’ve had a difficult time defining bone edema in a classification scheme.  And without a classification scheme, we then have a difficult time answering that question…how long will this bone edema injury take to heal.

In my practice (foot and ankle care), I’ve tended to find that when we discover bone edema on an MRI, the injury may take as long if not longer than most fractures to heal.  For instance, a common foot problem that we’ll see is a metatarsal stress fracture.  If the stress fracture doesn’t show on plain x-ray, we’ll send our patient for an MRI.  And if that MRI comes back with a diagnosis of bone edema within the metatarsal, we then have an idea about overall time that it’ll take for bone healing.  What’s the typical duration of time for a metatarsal stress fracture?  I’d tell most folks 8-12 weeks.  But with bone edema in the metatarsal, it may take as long if not longer than a traditional fracture.

Additional variables that influence the duration of healing of bone edema include the size of the bone that is injured, the type of bone that is injured, the depth of the injury and the overall size. 

Unfortunately, until we can develop a classification scheme for defining the healing rate of bone edema, each doc just draws from his or her experince with previous patients and similar injuries.  So if your doctor recommends an MRI and your MRI comes back with a diagnosis of bone edema, be patient with your doc.  She/he will try to guide you with answers, but defining how long bone edema will take to heal can be a challenge.

Jeffrey A. Oster, DPM
Medical Director
Myfootshop.com

 

Mid-foot arthritis – how is it treated?

Osteoarthritis (OA) or what we often call the wear and tear kind of arthritis, becomes increasingly more common as we age.  We all know someone who’s had a hip or knee replaced as the result of osteoarthritis.  An injury to a joint can accelerate the onset of of OA, but for most patients we’re going to see that OA isn’t actually isolated to just one joint, but is commonly found in many joints throughout the body.

During the course of taking a history of a patient with suspected OA of the feet, one of the first things that I do is look at the patients hands.  Bumps on the knuckles of the fingers known as Heberden’s nodes are a dead ringer for OA of the feet.  Since we know that most OA is symmetrical, we can bet on the fact that a patient with OA in the fingers is also going to have OA in the feet.

OA of the feet is caused by either an early injury to the feet or due to a predisposition to OA.  An injury to the foot can be any number of different problems.  I’ve seen a a patient in her mid forties over the past several months who sustained an injury to her arch in a high school basketball game.  The injury, known as a Lisfranc’s dislocation was undiagnosed for all these years.  Over time, the untreated injury slowly progressed to a stage where the patient was unable to bear weight on the arch.

Another more common form of injury is repetitive use.  Structural deformities of the foot can place excessive and unbalanced (eccentric) load on the arch.  These structural deformities include a high arch foot, flat foot or metatarsus adductus.  With each step, this imbalance will apply excessive load to the foot resulting in an injury.  Over time, this will predispose a patient to OA.

How do you treat OA of the midfoot?  Methods used to treat OA are pretty much the same regardless of the location in the body.  Those methods include bracing, use of an anti-inflammatory or surgery.  As a foot surgeon, I’ll be the first to tell you that surgery on the midfoot for OA is difficult to say the least.  Success rates are not the best.  If we compare surgery on midfoot arthritis to say a knee replacement or hip replacement for OA, I can say with certainty that we have a long way to go to get better at our art.

Anti-inflammatories?  Anti-inflammatory medications can have mixed results when treating OA.  Some folks will respond to simple OTC medications like Glucosamine while others have difficult even with the most potent of Rx medication.  I think you have to keep in mind though that the further along the OA, the less effective the anti-inflammatory medication.

Now let’s get to the heart of what I really wanted to talk about, and that’s bracing.  Whoever invented the Oxford shoe was a genius.  Sure, it isn’t pretty, but when it was first invented, the Oxford shoe was used as a brace.  Over time we’ve incorporated it as a fashion statement.  Paint it white and put a little swoosh on the side and you’ve got a running shoe which is really an Oxford in disguise.

The attributes of an Oxford, when used as a brace, are three fold; stiff shank, tied upper and a little heel.  This combination of attributes not only protects the foot but also creates a brace that can support problems such as OA.  A little heel will weaken the calf to decrease force that is applied to the OA with each step.  And the stiff shank enables force from the calf to be carried where it is most effective at the ball of the foot.  And the ties?  The ability to tie the shoe simply lashes the foot to the stiff shank.  Honest, the folks that invented the Oxford really had it all figured out.

We’ll often tweak a shoe to work better when treating OA.  For instance, if you have a tennis shoe that has a soft shank, we’ll but a still carbon graphite spring plate into the shoe.  In that way you can still use your existing shoes and not have to buy new shoes. 

Treating OA can be rewarding is you just stick to the basics of care.  Bracing is so important in treating this condition.  But as mentioned above, bracing can be quite simple.  Many of us will already have the solution lying in the bottom of our clothes closets.

Jeffrey A. Oster, DPM
Medical Director
Myfootshop.com

Diabetic peripheral neuropathy surgery – how successful is it?

I find it interesting that there’s really no one, single agreed upon theory to explain the onset of diabetic peripheral neuropathy (DPN).  One of the many theories describes intraneural edema, or swelling within the nerve.  Swelling within the nerve is caused by a concentration of blood sugar in the nerve that creates an osmotic gradient, pulling fluid into the nerve.  This condition is particularly problematic at sites where a nerve rounds an anatomical corner where it , may sustain physical irritation from movement of adjacent soft tissue and bone.  Symptoms of intraneural edema include tingling and burning of the feet and legs.  This condition is often called crush syndrome.

As a lower extremity surgeon, I’m often asked whether surgery is a method by which diabetic peripheral neuropathy can be treated.  In all too many cases, the answer is no.  But in some cases, if we think about the theory above, we actually can treat diabetic peripheral neuropathy with a  surgical procedure.  This surgery is called external neurolysis.  External neurolysis is a technique whereby the surgeon releases the nerve from any entrapment.  Carpal tunnel is a good example of external neurolysis.  Although carpal tunnel isn’t traditionally performed to treat DPN, carpal tunnel surgery is the same technique where the outer (external) portion of the nerve is freed form any entrapment.

There are three location in the leg where entrapments of the nerves can commonly occur.  Not all cases require that all three sites are treated.  We refer to the number of affected sites by calling the condition, single crush syndrome (1 site), double crush syndrome (2 sites) or triple crush syndrome (3 sites).

Most importantly we have to ask: what is the success rate of external neurolysis for the treatment of diabetic peripheral neuropathy?  I tell my patients to hope for 60% improvement.  Is that too low?  Maybe.  But I want to build realistic expectations for these surgeries.  But if I can help a patient to feel their feet again, I may indeed be helping to save their limb.  When diabetic patients lose that ability to feel the floor, we call that ‘loss of protective sensation’ or LOPS.  Feeling is key to avoiding infections and ulcerations of the feet.  And restoring sensation can make a huge difference.

So is surgery indicated for the treatment of DPN?  Maybe.  You might want to sit and have a long talk with your doctor first to see if it may be indicated for you.

Jeffrey A. Oster, DPM
Medical Director
Myfootshop.com

What’s so important about heel lifts? (part 3 of 3: Achilles tendonitis)

Achilles tendonitis can actually be one of several conditions.  Each of these forms of Achilles tendonitis can be improved and even healed with the use of a heel lift.  Let’s talk a little bit about Achilles tendonitis and see how a heel lift can help.

Walking and running can be described in very simple terms.  When our mind decides to move in a specific direction, the mind sends a signal to the calf.  The calf fires and delivers a force to the ball of the foot.  The action created at the ball of the foot is to lift us and initiate a bit of a forward fall.  We break that fall by putting our opposite foot forward and the whole process begins again, lifting the body and perpetuating the forward fall.  The calf initiates this action by delivering force through the single strongest tendon in our body, the Achilles tendon.  Therefore the Achilles is put under stress again and again throughout the day.  In most cases, the Achilles can mend over a period of 24 hours.  But in some cases, chronic loading of the Achilles will result in an inflammatory change called Achilles tendonitis. 

So if we know that Achilles tendonitis is the result of repetitive load, common sense would dictate that we need to find a way to decrease that load applied to the tendon.  Our choice is to either decrease the number of steps we take in a day or to decrease the amount of load applied to the heel with each step.  And that’s the beauty of a heel lift.  By elevating the heel, we weaken the load applied to the Achilles tendon with each step.  So rather than limiting our activities, we can still be active and heal with the use of a lift.

Jeffrey A. Oster, DPM
Medical Director
Myfootshop.com

What’s so important about heel lifts? (part 2 of 3: plantar fasciitis)

I had an interesting conversation with a patient this morning about plantar fasciitis.  The patient had classic signs of plantar fasciitis that included pain upon initial weight bearing and relief of pain with rest.  In her research on the Internet, she had found that most informational sources stressed support of the arch with an arch support.  “I was ready to spend over a hundred dollars at a foot care web site but thought I better check with you first.”  And I think my patient was very surprised to hear from me that plantar fasciitis had nothing to do with arch support.  It has everything to do with the height of the heel.

In part one of this series on heel lifts, we talked a bit about the mechanical forces that are generated by the calf and how those forces are distributed in the foot.  A fine balance exists in the leg, ankle and foot that performs well in young patients, but tends to develop problems as we age.  You see, the calf generates force with each step that we take.  In optimal biomechanics, that force is distributed to the foot in a way that lifts the body and enables forward motion.  But as we age, we start to loose tissue elasticity.  We still have the strength to perform the activities that we want to, but we lack the elasticity to heal.  And that’s what’s at the heart of what causes plantar fasciitis.  Essentially, the strength of the calf overwhelms the ability of the fascia to heal.

And what about the humble heel lift?  A heel lift is used to treat plantar fasciitis in a somewhat indirect manner.  By elevating the heel, you’re weakening the force generated by the calf.  Decreasing the force delivered by the calf to the foot decreases the load applied to the fascia and enables the ability of the fascia to heal.  It’s pretty simple really, raise the heel and the plantar fasciitis will get better.  Lower the heel (barefoot, low heeled shoes) and the plantar fasciitis gets worse.

So I ask you, if you had plantar fasciitis and were looking for cost effective treatment which would you choose; an Rx orthotic at $250(+)/pair or a heel lift at $3.95/pair.  And that’s the point in our conversation that my patient said to me, “man, am I glad I stopped to see you first.”

Treatment of plantar fasciitis doesn’t have to be complicated.  And it’s important to recognize that not all patients will be pain free with the use of a heel lift.  But in my experience, 7/10 are at least 50% improved within 3 weeks.  Not a bad success rate for the humble little heel lift.

Jeffrey A. Oster, DPM
Medical Director
Myfootshop.com