Bursitis is a very common condition that leads to foot pain . Once you understand what it actually is you will wonder why it does not occur more often, particularly in the foot.
It is an inflamed bursal sac. A bursal sac is a sac filled with fluid that acts to lubricate and reduce the friction between two surfaces in the body, usually muscles and tendons as they glide over bony prominences, however their purpose in not limited to just muscles and tendons.
The body contains literally hundreds of bursal sacs but in the foot there is just one naturally occurring (adventitious) bursal sac. It is located between the Achilles tendon and the heel bone (calcaneaus), otherwise known as an achilles tendon bursal sac. Note the yellow circle in the picture below. In this instance the Achilles tendon is protected from the pressure of the heel bone pressing against it when we walk.
HOW DOES IT OCCUR
In the foot we have a unique situation in that between the shoes that we wear and the ground that we walk on various parts of the foot are constantly being “micro” traumatized meaning that every time we take a step we do a small amount of damage to a particular part of the foot and eventually that part of the foot begins to hurt.
The body’s response to this micro-trauma is to create a bursal sac to initially protect the area but if micro-traumatized enough the bursal sac itself becomes inflamed and we have a bursitis.
In the two pictures below, the red circles represent the most common, but not only, sites for inflamed bursal sacs.
For people with a bursitis secondary to hammertoes the top of the toes are so close to the irritating shoes that the constant rubbing of the toe on the shoe may form a bursitis, (a corn may also occur). The top of the toe will typically be very tender, mildly swollen and red. Pressing on the swollen area will cause a fair amount of pain. If barefoot, the toe will generally not hurt, but even socks or stockings can cause pain. If the toe is rubbed too much by the shoe, the bursal sac can burst on its own and usually becomes infected.
This problem may also form on the sides of the foot in the area of a bunion or tailors bunion. In fact the true definition of a bunion is the enlargement of the metatarsal bone, deviation of the big toe towards the second toe, and the formation of a bursitis. Again, this is nothing more than too much pressure and friction occurring on the bony prominences of the foot.
In addition to the normal occurring bursal sac on the back of the heel that may become inflamed, many times there will develop an area of mild redness, swelling and tenderness just off center to the back of the heel. This is referred to as a “pump bump”. Due to the enlargement of the calcaneus (heel bone) on its posterior aspect and the constant pressure of a shoe, usually a women’s dress shoe, the body will form a bursal sac that eventually becomes inflamed.
Patients will relate that the site hurts while in shoes but most times will feel better without shoes or be improved with very conservative shoes, but any outside pressure on the spot will cause pain, such as the heel hitting the mattress if you sleep on your back.
This problem may also form on the bottom of the foot generally on the ball of the foot and in the heel. Unlike the bursitis we have discussed these are usually not visible because they are deep to the fat layer on the bottom of the foot.
When dealing with pain on the ball of the foot under the metatarsal heads, a bursitis has to be a consideration along with capsulitis, neuroma
, and sesamoiditis
. Generally, when a patient complains of burning on the ball of the foot, neuroma and bursal sac are the first two things I explore.
Lastly, when diagnosing heel pain many times I include heel bursitis as a source of the pain. In the symptomatic heel if the patient complains that the more they walk, the more the heel hurts, then I have to consider a bursitis heel as part of the problem. Over the years I have actually removed an inflamed bursal sac from the heel during heel spur surgery.
So what can you do to alleviate this type of pain in the foot? If the bursitis pain is occurring on the toes, bunion or back of the heel area the smart money would be on eliminating the shoes that seem to aggravate the condition. Eliminating these shoes may not in itself clear up the problem but you can be sure that if you continue to wear the offending shoes nothing you or your doctor do will permanently “fix” the problem. A recurring theme that I use throughout this site that if you put an abnormally shaped foot in a dressy shoe it is literally the same as trying to put a square peg in a round hole; it will not fit.
Icing the area during this period may also help reduce the symptoms.
If the bursitis is occurring on the bottom of the foot, trying an over the counter arch support may help in an effort to redistribute body weight and take pressure off the painful area. If that only affords you some relief, you may have to consider orthotics.
We, as foot specialists have a few things we can do to reduce the pain. If the bursal sac is very superficial we can usually drain the sac, which will usually alleviate the problem, but with the warning that if the offending cause is not eliminated the problem may return.
Other times we give cortisone injections, which can relieve the pain of the bursal sac. For those who want very conservative care, orthopedic padding may reduce the inflammation by taking the pressure off the bursal sac. This can be very helpful in the toe area.
Physical therapy, usually for the deep type of bursitis is also helpful.
Lastly, of course, is surgical intervention. Correcting a bunion or fixing a hammertoe may be the only solution for some people to ultimately rid them of their pain. Be sensible in your problem and try all the conservative things first, if they do not help then surgery may make sense.