A collegiate runner, several weeks into his indoor season, begins to experience heel pain. He first feels it at the end of a cold long run. It worsens throughout the week and flares badly following an intense indoor track workout spent circling the 200-m oval at high speeds and on his toes. Pain was bearable during but causes a limp on the cool-down...and walking to class following the track session.
What to do?
Everyone -- teammates, coaches, trainers, doctors, and most PTs -- would tell him to "R.I.C.E.": Rest, Ice, Compress, Elevate. Maybe some stretching and, if you have the luxury, some ultrasound and massage.
So that's what he did. All of the above. While doing so he rested, and cross-trained, and waited. And waited. And waited. Days turned into weeks, then months. Yet it was still painful to load -- and even to the touch -- and even seemed to "throb" at rest.
Then what? X-rays? MRI? Psychiatry?
How about some additional information?
- The runner had NO morning stiffness or pain. Moreover, he had very little pain doing a calf raise, and even less stretching the affected Achilles tendon.
- He also reported the heel was painful at rest -- sitting in class, or in the car on long drives between school and home -- where he reported a "burning, buzzing feeling".
- Several weeks prior to the injury, the athlete was on winter break from school, where he was able to rest and relax doing a variety of things with his free time. However, just two weeks before injury onset, school re-started. This meant 6-8 hours per day class and 3-4 hours nightly studying, slouched uncomfortably in lecture hall chairs, or hunched over a book 'til the wee hours of the night.
It is at this point when you look at the moo-ing duck and call it what it is: A well-disguised COW. In this athlete's case, the source of his heel pain was his back.
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The human spine (or more accurately: vertebral column) contains (depending on how you count), 25 individual bones: 24 vertebrae and a sacrum -- a bone that serves as the keystone, connecting the pelvis to the spine, and a conduit for the violent ground reaction forces generated by each stride we take while running. Given that during easy running we transmit over 6 times our body weight in force with each step, it's no small miracle we don't rattle to pieces a mile down the road.
And between each of these bony vertebral segments flow the nerves controlling everything in our extremities: our voluntary motions, as well as sensations from the world around us, including pain.
"Flow" is a generous description. SQUEEZE is a more accurate description of a nerve's route from the spinal cord to their area of innervation. They tunnel their way, through tiny caves at the vertebrae, around other bones, between (and sometimes through) muscles until they reach their final destination.
And based on this description, it's no surprise that these biological powerlines often become squeeze, kinked, or otherwise aggravated -- with negative consequences.
Nerve Irritators: The Usual Suspects
The following structures are usually most responsible for nerve irritation and non-soft tissue extremity pain.
Vertebral Discs
Most of us have heard of "herniated" or "bulged" discs. We tend to think that disc pathology can occur only with severe injury. However, our vertebral discs are relatively mobile. Though microscopically, they can slide around between the bones and ever-so-lightly encroach on the nerve exiting the cord -- just enough to cause nerve-related pain down the chain.
Vertebral Joints
Joints connecting adjacent vertebrae lie on either side of the column, allowing for a variety of motions. If these joints become irritated -- usually by becoming too stiff -- they can affect the nerve roots that pass just millimeters above and below them. Indeed, these facet joints, themselves, can cause pain farther down into the arms and legs!
Soft Tissue
Muscles, fascia and other connective tissue can impede the smooth flow of nerves to their destination. Chronic muscle tightness -- that which comes from daily, punishing bouts of endurance training -- can compress and adhere to nerves, creating pain.
*****
In the case of our runner, his nerve irritation resulted in posterior heel pain closely mimicing Achilles tendonitis. However similar, it did not act like tendonitis (remember the Soft Tissue Rules of the Game?).His pain description also missed the boat. While strinkingly similar to soft tissue injury -- the classic pain with weight-bearing -- there were several subtle differences that, in the end, led to calling that duck a cow.
Pain Behavior: Soft Tissue v. Nerve
Here's a list of differences (some more subtle than others) between soft-tissue and nerve irritation:
Pain Location
- Soft Tissue: "Point-tender" (able to point to one specific area of greatest pain)
- Nerve: large, undefined area, capable of "moving around" ("around the heel, sometimes on the inside of the ankle...")
Most Painful
- Soft Tissue: In the AM, first beginning exercise and/or at fatigue
- Nerve: gradually worsening, worst with spinal loading/impact
Hurts to Stretch
- Soft Tissue: YES
- Nerve: RARELY
Hurts to USE
- Soft Tissue: YES
- Nerve: Usually only in weight-bearing (putting compression on spine); RARE to have any pain out of weight-bearing (e.g. resisted dorsiflexion in sitting/supine)
Morning Pain/Stiff
- Soft Tissue: YES
- Nerve: RARELY
Pain at REST
- Soft Tissue: RARELY (unless injury is acute, or acutely flared)
- Nerve: YES
WEIRD sensations: burning, aching, pins-and-needles, hypersensitive to touch
- Soft Tissue: RARELY
- Nerve: YES
*****
So You Think It's Not Tissue: Now What?
As "big picture" health care professionals, whenever we get a referral diagnosis, our first thought is, "What else could this possibly be?"
When nerve pathology is suspected, we confirm it with:
Treating Nerve-Related Pain
Our injured runner had the following problem list:
As "big picture" health care professionals, whenever we get a referral diagnosis, our first thought is, "What else could this possibly be?"
When nerve pathology is suspected, we confirm it with:
- A thorough subjective (pain onset and behavior, history of back pain, or related "odd" limb complaints?)
- Nerve/spine special testing
- Spinal mobility and stability testing
Treating Nerve-Related Pain
Our injured runner had the following problem list:
- Poor back mobility: his flexion was OK, but he was limited in extension by at least 50% (e.g. he could not do a full backbend, which a man of his age and fitness should be able to do)
- Poor lumbopelvic stability: he demonstrated poor core strength and activation during running
- Poor posture: he reported sitting, standing and lying in poor, flexed postures.
After less than two weeks of this simple treatment approach, this runner's pain reduced enough for him to resume training, and within four weeks was gone completely.
Keeping it at Bay: Tips for Good Back Health
Mobility. Spine mobility is the most important factor in alleviating -- and preventing -- back and extremity pain. Three "gold standard" flexibility milestones:
- Touch your toes. One should be able to touch his or her toes, while keeping the knees straight.
- Lying backbend (aka "the upward dog"). One should be able to come close to locking out elbows on this modified push-up, while keeping their pelvis on the floor.
- Lumbar rotations. Lying flat, flex your hip up to your waist and "fold over". One should be able to touch the knee to the ground while keeping the other arm firm to the ground.
Posture! Watch your posture in whatever you do: sitting, standing, lying. Stay out of prolonged stressful positions, especially flexing forward.
*****
So, next time you think you've got a duck on your hands, treat it as such. But if it's not improving -- and you start to hear some "moos" -- you just might have a cow on your hands.
