It’s the high cost of hospital real estate, stupid. That’s what I keep telling myself whenever I vainly search for a convenient, lengthy corridor that my patients can pace. In their zeal to maximize every possible square foot of space, hospital architects have all but eliminated those dated, boxy hallways that lead to nowhere. No matter. I need a long passageway! Despite all the advances of modern medicine, gauging how someone saunters down a hallway can speak volumes about the state of their health. You get to see your patient in motion. Are they hobbling along in pain? Is their stride too short or too long? Does their body sway to and fro? Having them parade around your cubbyhole can be an exercise in futility. After all, taking four consecutive steps in most hospital exam rooms will direct your patient headfirst into an immovable structure, such as a desk, an exam table or a wall.
Too often, physicians skip over this critical part of the musculoskeletal exam. Feeling pressed for time, some are looking for corners to cut in their brief office visits. Trying to stay on schedule, they are searching for some precious time when they can enter all the requisite—though often meaningless—data points into the patient’s ever expanding electronic record. Others may naively believe that having the patient lying supine on an exam table and rotating their hips or flexing their knees is sufficient to assess a complex weight-bearing activity, such as walking. One former colleague even challenged the idea of marching a patient down an open hallway as a possible violation of their privacy rights as defined by the Health Insurance Portability and Accountability Act (HIPAA). Because heavy fines or even jail time face HIPAA violators, the mere sound of this acronym strikes fear in our hearts. So far, I haven’t heard about any rheumatologists being led away in handcuffs.
Gait Still Matters
Despite the emergence of several useful scoring systems to assess functional status, watching how a patient walks is always far more informative than reading their self-characterization of their locomotor abilities in a health assessment questionnaire. A viewing is worth a thousand words.
This was patently clear when I recently met two new patients with rheumatoid arthritis (RA) whose chief concern related to their progressive difficulty walking. Margaret was a middle-aged woman with a lengthy history of RA that, until recently, had been reasonably controlled with a combination of drugs. Lately, she had noticed that she was starting to stumble when she walked. She felt as though she were drunk. Her occasional stumbles multiplied to the point that she could no longer safely leave her home. Her rheumatologist speculated that her decline must have been the consequence of having a severe peripheral neuropathy related to her RA. However, she could not recall how her doctor established this diagnosis. The rheumatologist neither tapped her reflexes nor referred her for any electrical studies of peripheral nerve function. She most certainly did not ask Margaret to walk.
Margaret meandered slowly down the corridor. She wasn’t lying: She really walked as though she were drunk. This reminded me of a clinical pearl taught to me by a wonderful, old-school neurologist who loved examining patients: If the patient walks like a drunk but hasn’t had a drink, focus on their cervical spinal cord.
Margaret’s fluttering ankle jerks and pathologic dorsiflexion of her big toes confirmed this adage to be true. It turned out that an old problem unrelated to her RA had resurfaced. Imaging studies confirmed the presence of very severe cervical spinal cord compression caused by the architectural changes imparted by her longstanding cervical spondylosis. Unlike severe peripheral neuropathy, which is generally resistant to treatment, cervical myelopathy can sometimes be remedied by surgery.
My other new patient, Cindy, was a delightful, upbeat nanny who seemed to be struggling with her RA. Although her peripheral arthritis seemed to be under reasonable control, she was frustrated by her declining ability to walk, a rather dire situation for an active 43-year-old woman. She kept experiencing episodes in which her arms and legs “went numb.” Although she rarely fell, this eerie sensation would halt her in her tracks.
I was stumped when I met Cindy. Her neurologic function was intact, and there were no obvious clues. She came armed with a Google search of her symptoms, which concluded that she might be developing multiple sclerosis. It was a reasonable consideration for a patient being treated with a tumor necrosis factor inhibitor who was experiencing recurrent, widespread neurologic symptoms.
The magnetic resonance imaging (MRI) study of her brain was striking. The brainstem, that precious piece of matter whose simple name belies its preeminence, was being impinged by her occiput. A severely damaged atlanto-axial joint, whose normally taut ligaments had been shredded by the adjacent mass of inflammatory rheumatoid pannus, precipitated this worrisome sequence of events. Now Cindy’s upper neck was free to jab the base of her skull. In essence, her atlas was dropping the ball or, shall we say, her head.
The generally sturdy and reliable C-1 vertebra, the atlas, was named for the primordial titan whose punishment for being disloyal to the Greek god Zeus was to carry the heavens on his shoulders forever. In healthy individuals, it carries our heads fairly effortlessly. Needless to say, a few millimeters of tissue shifting in this highly sensitive area can make all the difference between capacity and incapacity.1
There was hope for both Margaret and Cindy. To paraphrase William Shakespeare, what’s done can be undone—especially in the hands of a skilled spine surgeon.
The neck is not the only critical locomotor intersection between neurology and rheumatology. For example, in patients with stiff-person syndrome, autoantibodies circulating in the brain target the enzyme glutamic acid decarboxylase, rendering ineffective most of the inhibitory motor pathways that regulate muscle contraction. The resulting Frankenstein gait is a memorable term that aptly describes the ensuing stiff, awkward walking style. Once you have seen it, you will never forget it. Similarly, when examining patients with vasculitic neuropathy, you hope not to hear the slapping sound of a denervated foot striking a hardwood floor. This is a sickening noise, heralding the major therapeutic and rehabilitation challenges facing a patient with a foot drop.
Standing Straight
Walking is an integral activity in our lives. However, walking upright is a relatively recent development in the evolution of apes and human-like creatures, the hominids, having occurred just a few million years ago. With a paucity of supporting evidence, Charles Darwin speculated that humans evolved in Africa and were most closely related to the African great apes. He also reasoned that the origin of bipedal locomotion was a critical event, one that set humans on a separate evolutionary trajectory from their ape relatives.2
The continued stubborn resistance of osteoarthritis to most, if not all, therapeutic interventions assures the long-term viability of the orthopedic implant industry.
According to Daniel Lieberman, PhD, professor of biological sciences at Harvard University in Cambridge, Mass., Darwin believed that natural selection favored an ape that stood upright, freeing its hands to carry objects and to make tools. Although walking upright reduced energy costs and liberated the hands, it also constrained our ancestors to be slower creatures. Their competition, the other apes and chimpanzees, were knuckle-walkers, a faster but more energy-expending form of locomotion. The loss of speed when walking upright was compensated by the ability of hominids to become endurance walkers and runners. This development provided a great advantage for our ancestors who could now pursue their prey and outlast them in the chase. Their diets shifted from eating plants, shoots and berries to rich animal protein, laden with fat and marrow. The original Paleo diet! Having access to protein and fat may have enabled a very significant evolutionary breakthrough. It was only after this dietary change that the hominids’ brains began to enlarge. It seems that the previously low-calorie, low-cholesterol diet constrained the size of the brain, a costly organ to grow and to maintain. Hominids became better skilled at hunting, and their newly acquired social skills enabled them to collaborate with others to capture prey that previously was too powerful or too fast to kill. Larger brains offered more advanced linguistic and cognitive abilities. In short, Darwin’s speculation was that without bipedalism, humans might never have evolved.3
How did a knuckle-walking ape transform to an upright, bipedal hominid? Not quickly. A number of musculoskeletal changes occurring over a period of several million years supported this shift to bipedalism. In order to walk, hominids had to sacrifice their agility as tree climbers. Their spines needed to be redesigned to include a lumbar curve to position the upper body above, rather than in front of the hips, and femurs had to be angled inward so the knees would be more centrally positioned than the hips. Hips became curved to the side, permitting the muscles along the side of the pelvis to stabilize the body’s center of gravity when one foot needed to be planted on the ground. The hominid foot began to resemble the human form, with robust heels, a large big toe partly in line with the other toes and a partial arch.3 Perhaps one of the most important yet overlooked changes in body structure was related to foot pronation.
Pronation is an important motion that shifts weight onto the medial side of the foot in climbing apes and serves a role in weight transfer, shock absorption and negotiation of uneven surfaces. As apes descended from the trees and transformed from being climbers to walkers, they needed to be able to accommodate both terrains. This required an increasingly mobile foot that could provide support along its medial pronated aspect, along with strong, stabilizing anatomies at the knee and the hip.4 These highly intricate foot biomechanics evolved over millennia. The end result was the human foot, which the Renaissance polymath Leonardo da Vinci considered, “a masterpiece of engineering and a work of art.”
Walk On
Fast forward a few more millennia and here we are today. When a weight-bearing joint fails to function, it can now be replaced. One can only imagine the difficulties facing a patient with advanced osteoarthritis of a hip or a knee living any time prior to the latter half of the 20th century. There were no realistic ways to address the misery of end-stage osteoarthritis. For the afflicted patient, ambulation was severely limited, and without narcotic analgesics the pain was nearly continuous. Life was miserable.
It was just a little more than 50 years ago that John Charnley, a British orthopedic surgeon, created the first successful hip implant. Within a few decades, knee arthroplasty became a widely available procedure. The continued stubborn resistance of osteoarthritis to most, if not all, therapeutic interventions assures the long-term viability of the orthopedic implant industry.
Serious strides have been made for another group of individuals who have lost their ability to walk, not because of joint disease or other effects of aging on the skeleton. These are the soldiers and civilians who have had their feet and legs ripped from their bodies by explosive devices. Although most of these victims have come from war zones, where buried land mines and roadside improvised explosive devices (IEDs) are rampant, we recently witnessed the chaos and madness of IEDs planted in the heart of downtown Boston at the 2013 Marathon finish line.5 It has been incredibly heartening to see how several of the victims of this blast have already regained their ability to walk, run or dance.
In separate ways, nature and science have made striking advances to advance human locomotion. In the process, our brains have grown in size, but has that made us smarter? If so, then it shouldn’t be too difficult for humanity to figure out how to stop killing and maiming one another. We don’t have a millennium to waste.
Simon M. Helfgott, MD, is associate professor of medicine in the division of rheumatology, immunology and allergy at Harvard Medical School in Boston.
References
- Laiho K, Kauppi M, Konttinen YT. Why Atlas, why not Heracles: Reflections on the rheumatoid cervical spine. Semin Arthritis Rheum. 2005 Feb;34(4):637–641.
- Darwin C. The Descent of Man, and Selection in Relation to Sex. John Murray. London, England. 1871.
- Lieberman D. E. (2010) Four legs good, two legs fortuitous: Brains, brawn and the evolution of human bipedalism. In the Light of Evolution. Ed. Jonathan B. Losos. pp. 55–71. Greenwood Village, Colo: Roberts and Company. 2011.
- DeSilva JM, Holt KG, Churchill SE, et al. The lower limb and mechanics of walking in Australopithecus sediba. Science. 2013 Apr 12;340(6129):163–165.
- Guermazi A, Hayashi D, Smith SE, et al. Imaging of blast injuries to the lower extremities sustained in the Boston marathon bombing. Arthritis Care Res. 2013 Dec;65(12):1893–1898.
Corrections
In “Diagnosing Axial Spondyloarthritis” by Atul Deodhar, MD (The Rheumatologist, May 2014), the source for Figure 1 was inadvertently omitted. The credit should have read: Adapted from van Vollenhoven RF. Nat Rev Rheumatol. 2011 Apr;7(4):205–215. We regret the omission.
The article “JAK Inhibition in RA” (The Rheumatologist, July 2014) inaccurately reports that tofacitinib was approved by the FDA in November 2012 for use in psoriasis, stating: “Tofacitinib was approved by the FDA in November 2012 for use in psoriasis and in RA for patients who have had an inadequate response or intolerance to other therapies.”
Please note that tofacitinib is not approved for the treatment of psoriasis. XELJANZ (tofacitinib citrate) 5 mg tablets are indicated for the treatment of adults with moderately to severely active rheumatoid arthritis (RA) who have had an inadequate response or intolerance to methotrexate (MTX). XELJANZ may be used alone or in combination with methotrexate or other non-biologic, disease-modifying antirheumatic drugs (DMARDs). Use of XELJANZ in combination with biologic DMARDs or potent immunosuppressants, such as azathioprine and cyclosporine, is not recommended. Please visit the direct link to the full prescribing information for XELJANZ, including boxed warning and Medication Guide: http://labeling.pfizer.com/ShowLabeling.aspx?id=959.