This gentle lady, a 48 year-old hairstylist, began having problems at the ball of her left foot three years prior to visiting me. The chain of events she related in her history distressed me. She first visited a podiatrist who offered no diagnosis, but made her a pair of orthotics that actually caused her more discomfort. She discontinued using them. She visited a second podiatrist who diagnosed her problem as a neuroma.* He made her a new pair of orthotics, which didn't hurt her feet, but didn't help either. She then visited a third podiatrist, who told her there was no such thing as a neuroma, and built up the metatarsal pads** on her orthotics. The build-ups were mildly uncomfortable, but she persisted in using them because all three podiatrists suggested she should use orthotics. She continued this way for two years, the pain at the ball of her foot worsening, searing, burning, limping pain, then spreading to her right foot, despite wide soft shoes and using her orthotics even when she was walking around her house. There had to be a reason for this logarithmic increase in pain despite her diligence and the care of three doctors. She decided to visit an orthopedic surgeon. He performed surgery, removing two "tiny" neuromas from each foot. She wore surgical shoes for two weeks postoperatively until her sutures came out. During that time, she was finally pain free for the first time in two years. Then she returned to her sneakers, and the orthopedist advised her to continue using her orthotics to prevent recurrence of the neuromas.
Unfortunately, her pain soon returned. She revisited the third podiatrist, whose solution was to further build up the metatarsal pads. Her pain continued to worsen, at the same sites as prior to surgery. Just before visiting me, she met a pain-management physician who inserted cold probes between the bones at the balls of her feet to freeze any remaining nerve tissue. Her pain persisted. She decided to close her hairstyling business, leave New York City, and move to California, where she could have a car and not have to walk anymore. Her pain had increased to the point that she couldn't walk one block without having to stop. As a last resort, she thought she'd visit one more doctor in New York City before closing up shop.
I began my hands-on examination. There were big surgical scars on her feet, but I could detect no sign of a neuroma after repeatedly doing the three hands-on tests I often do for them. I looked inside the spaces between the bones with my ultrasound machine. There was no sign of a neuroma. There was some inflammation just beneath to the skin immediately behind the balls of her feet. I palpated the site which I'd seen was inflamed on the ultrasound scan. "That's it, that's the pain. Nothing can make it go away." She began to cry. After meticulously palpating the balls of her feet, and talking to her, I decided the symptoms she was complaining of were not typical at all of neuromas, due to their location, nor were they typical of another common problem at the ball of the foot, bruised joints, again, because of the location of her symptoms. The tenderness was located not where one would bear weight, i.e., beneath the joints at the ball of her foot but rather it was sequestered behind these joints. It was towards the bottom of her arch, just behind the ball of her foot, in an area hidden from ground-contact. It was in the exact same spot on both feet, about an inch wide, and wow, was it exquisitely tender. Why would something be so symmetrical, foot-to-foot? So tender, though not in a weight-bearing area? And what would cause a problem to hurt small sections of different muscles, tendons and skin, unlike any entity ever published? There is only one answer, but no one had ever posed the question. The answer was trauma. But she'd never twisted her foot, dropped anything on it, or stubbed her toes or jumped from a high place, etc. Where could trauma be coming from? I marked the sites of exquisite tenderness on her feet with my skin-marking pen, and then carefully pressed her orthotics up against her feet. I confirmed my suspicions upon inspecting the orthotics: there were the huge purple dots from my skin-marking pen peppering the orthotics' metatarsal pads. The scariness of my solution was in its simplicity. I advised her to stop using her orthotics. She called me one week later. Pain gone.
I believe her problem initially may have been due to incorrect shoes or some other transient circumstance which may have caused neuroma-like symptoms. Before a neuroma develops, the nerves between the metatarsal heads are pinched. I believe she had pinched nerves, or "pre-neuromas". I think the metatarsal pads caused the greatest duration of her discomfort. Despite helping this patient, I'm left with a sense of inadequacy when I reflect upon this case. There was no glory in my solution. I had no reassuring words to make up for the pain and disability she'd endured. I had nothing to say to redeem my colleagues. She must have felt like someone who was wrongfully imprisoned for three years, and I was simply the guard who booted her out onto the street. But for the sake of all of us, this wretched case illustrates two parameters that have evolved upon reflection into mainstays of my practice ethos:
* A neuroma is an accumulation of scar tissue around a nerve. Neuromas can occur anywhere nerves are. In the foot, they most often occur between the bones at the ball of the foot where the 3rd and 4th, or less commonly, 2nd and 3rd toes connect. The scar tissue builds in response to forces squeezing these bones together, bruising the nerve. Like a "cauliflower ear", in which the boxer's or the rugby-player's ear builds a visible cauliflower-like wad in response to repetitive bruising, a neuroma will increase in size if subjected to continued compression, like from ill-fitting shoes. Eventually the scar tissue builds to a point where pressure from shoes or from the ground cause shooting pain at the ball or toes.
** Metatarsal pads are mounds, usually an inch or so in diameter and up to a half-inch high, fixed on the top of orthotics, situated just behind the joints at the ball of the foot. The idea behind metatarsal pads for neuromas is to use the mounds to spread the bones compressing a neuroma away from each other, as the bones cascade down the slopes of the mound.