When I protested feebly that I'd just turned 27, he threw up his arms and laughed. "I know—terrible, isn't it? Now don't forget to say hi to your mother for me, or you'll be in big trouble!" With that, he called for the next patient.

I tried, in the ensuing months, to embrace this philosophical outlook, to regard my pain with detached stoicism. By this past February—after traveling, with mixed results, to China and then to India in search of alternative remedies—I'd given up on fixing my shoulder for good and sought only the occasional stopgap. Back in Texas, I began receiving weekly vitamin B-12 injections from a protégé of Dr. Janet Travell, whose trigger-point injectionsof procaine JFK said got him through his Senate term and into the White House. To show his gratitude for these injections—and doubtless also for herlies about his health in the run-up to the 1960 election—JFK appointed Travell his back doctor and also the first, and to this day only, female chief White House physician. I liked this oblique connection to presidential (and feminist) history. I didn't care that the B-12 injections were expensive ($250) and their benefits short-lived, lasting a week at best.

But satisfaction, like some psychiatry services, operates on a sliding scale. Four injections and $1,000 after my first visit, temporary relief was no longer good enough. When I returned to New York, a friend advised me to contact Dr. Norman Marcus, who runs an eponymous pain institute a few blocks from Grand Central. Dr. Marcus, it turned out, was the protégé of another Kennedy back doctor, Hans Kraus. He reintroduced the question posed on umpteen topics, from Vietnam to civil rights: What if the president had lived? In this case, the follow-up was: Might the history of back pain have been different?

Kraus began treating JFK in October 1961. Over the next two years, the president submitted to supervised strengthening exercises and occasional "needling" procedures to soften the knots and break up the trigger points in his muscles. Kraus' treatment produced spectacular results. The back pain that had dogged Kennedy since late adolescence gradually diminished, and legend has it he was almost ready to remove the corset that kept him catastrophically upright after the first two shots were fired from the Dallas book depository.

Kraus and now Marcus think the most pervasively undiagnosed cause of pain is muscular in origin. It's a pretty straightforward theory: Because muscles account for more than 50 percent of the body's weight, they must surely be responsible for some of the body's pain as well. Curiously, though, there is no standardized diagnostic label for muscular pain, no universal treatment protocol. Over the past 19 months, I'd consulted endless highly recommended specialists—orthopedists, neurologists, neurosurgeons, chiropractors, acupuncturists, physical therapists—and not a single one had so much as mentioned muscles.

At my first meeting with Dr. Marcus, I was surprised when he didn't demand to see my MRIs or X-rays. He told me he considers imaging studies overused, no substitute for the good, old-fashioned physical exam. Dr. Marcus began by asking me what hurt and where, and during which activities. Then, after kneading my back and evaluating my range of motion, he used an electrical "muscle pain detection device" to contract my muscles and reproduce the motions of everyday activities. This step is crucial, he told me, because most exams assess bodies at rest, while people with muscle injuries usually experience pain in action.

On my back, the instrument glided painlessly over the scapular peninsula that throbbed and pinched after five minutes of typing or driving—a common enough occurrence, Dr. Marcus explained, since we don't necessarily feel pain at the place where it originates. And sure enough, at the infraspinatus and the teres major, almost a hand's width away from my scapula, the device that had passed so smoothly over my central back caused me to yelp out loud.

Dr. Marcus could now treat the trigger points. Several days later, I showed up at his office on an empty stomach. He injected Demerol into my arm, numbed my back with topical lidocaine, and—before I could finish telling him about my weekend—began stabbing my back with a needle, mashing up the hardened tissue there. If this sounds dramatic, trust me, it wasn't. I felt no pain until later that evening, and within the hour, I was crumpled in a taxi, en route home. Later that evening, I examined my back in the mirror and was delighted by the reticulation of red dots zigzagging its contour.

For the next three days, I returned to Dr. Marcus' office for physical therapy. He hooked me up to a neuromuscular electrical stimulator that rehabilitates the injected muscle. He also taught me the upper-body Kraus-Weber exercises his mentor developed in the 1950s, which are critical for the upkeep of healthy muscles. Between appointments, I set the kitchen timer as a reminder to change my body position every 15 minutes. Several times an hour, I rose and circled the apartment, or harassed the cats, or ate, or practiced my exercises. Even with all these breaks, I got more work done than before, since I no longer retired to the tub after two hours.

By the end of the week, my knotted right shoulder, source of protracted, high-pitched agony, was squishier than a wet uncooked slab of steak. No Baywatch boob job has stirred such buyer's pride: I couldn't stop showing off my shoulder and its gorgeous new slope. But, as Dr. Marcus warned, the injury so long untreated has given rise to smaller aches and imbalances. Without hesitation, I made an appointment for another round of injections, this time targeted at my pectoralis major.

Following this treatment, I woke up a little looser every day—almost, astonishingly, pain-free. I'm functional for the first time in 19 months, but I'm still not, as the sportscasters say, 100 percent. And now that's what I want. I don't have to get my scalene muscles injected next week, but why shouldn't I? If my pain is treatable, why shouldn't I treat it?

No more adapting for me, no more aging before my time. Along with reading in bed and watching TV lying down—both major causes of the isometric muscle contractions that lead to trigger points—I've given up browsing catalogs filled with wheelchairs and quad canes. Don't get me wrong, I still like a good orthopedic sandal. But after next week's injections, I think I'll buy a new pair of running shoes instead