Orthotics provide significant benefits by improving biomechanical function during gait and decreasing skeletal impact
At the recent World Federation of Chiropractic Congress in Paris, I was discussing the use of orthotics with several doctors of chiropractic. While describing the technical aspects of providing and fitting orthotics for patients, one doctor—who had been listening, but not contributing—said, “Why do chiropractors need to use orthotics? I don’t use them in my practice, and I don’t see what the big deal is.”
Since orthotics have been an integral part of my practice of chiropractic and rehabilitation for many years, his question startled me. It made me realize that there are still many DCs who do not appreciate the value and benefits of orthotics for their patients. On the verge of listing the spinal and lower extremity conditions that can be improved with the effective combination of chiropractic care and orthotics, I then realized that a laundry list of conditions was not the underlying factor in using orthotics. Instead, my response was, “There is only one reason a chiropractor should use orthotics, and that is to benefit our patients.”
Buffer Zone
The benefits of orthotics fall into three areas: 1) alleviates many symptomatic musculoskeletal conditions, 2) improves musculoskeletal efficiency and sports performance, and 3) aids in the prevention of many problems. These benefits are due to the combination of improved lower extremity biomechanics and better absorption of repetitive skeletal impact.
Biomechanically, orthotics improve foot and ankle function by supporting the arches and reducing pronation forces. Excessive pronation interferes with gait, decreases athletic performance, contributes to the development of painful foot and ankle disabilities over time, and—especially pertinent for chiropractors—increases the probability of transferring abnormal stresses from the lower extremity to the pelvis and spine.
Domino Effect
The accurate timing of the many muscle contractions required during walking and running depends on stimuli from a symmetrical gait. Pedal imbalances, such as excessive foot pronation, whether in one foot or bilaterally, interfere with these carefully orchestrated movements and cause problems throughout the musculoskeletal system.
Neurological effects.
• Neuromuscular incoordination: Much of the smooth performance of daily physical activities occurs without the need for conscious thinking or planning, including balance, stability, and center of gravity.1 When one foot or both feet spend too much time in pronation, an abnormal gait pattern develops, and muscles throughout the body (and around the spine) do not turn on and off in proper sequence. This increases the work effort for doing simple activities as well as the oxygen consumption during normal walking.2
• Spinal imbalances: Many chronic myofascial problems are secondary to excessive pronation. Gait abnormalities, neurological incoordination, and asymmetrical structural stresses are compensated by excessive contraction of the large stabilizing muscles of the spine, which results in habits with detrimental effects on movement and perpetuation of symptoms. Myofascial trigger points, chronically-contracted muscles, and even thoracic outlet syndrome3 can develop when pedal imbalances persist. Because a smooth and symmetrical gait is tied closely to proper vertebral function,4 excessive pronation in one or both feet can cause subluxations to recur.
Structural effects.
• Pelvis misalignments: When a foot pronates during the stance phase of gait, there is a normal inward (medial) rotation of the entire limb and pelvis. In persons who have excessive or prolonged pronation, this twisting movement is accentuated. The increased rotational forces are transmitted into the pelvis, and especially the sacroiliac joint.5 In response, various compensatory pelvic subluxation complexes develop. These include pelvic tilts (usually anterior or to one side), innominate rotations (usually postero-inferior), and other complicated adaptations. Until excessive pronation is corrected with orthotic supports, only short-term relief can be achieved with chiropractic adjustments.
• Functional scoliosis: A loss of arch height allows the pelvis to drop to the more pronated side during stance and gait.6 The resulting pelvic tilt lowers the sacral base and drops the lowest freely moveable vertebra. A lateral curvature develops in response to the lack of solid support for the base of the spine. This functional scoliosis starts in the lumbar region, but can affect the entire spine. In young patients, this curvature disappears when sitting or lying on the examination table. As patients age, the spine becomes less flexible, and functional curves become stiffer and more fixed.
• Degenerative changes: Left untreated, the various structural responses to pedal imbalance listed above will eventually progress to joint degeneration. Biomechanical asymmetries transmit abnormal forces and sustained stresses to the joints, resulting in microtrauma, cartilage wear, and osteophytes.7 If patients already have significant degeneration, additional shock absorption will need to be included in orthotic prescriptions.
Excessive pronation is also the cause of many of the overuse injuries suffered by athletes.8 Often, these developing problems go unnoticed for months or years, and it is only when a new walking or recreational program is begun that symptoms arise. It is usually the painful endstage of abnormal biomechanics that brings in a patient for care. Be sure to check for symptomatic conditions and musculoskeletal pathologies associated with excessive pronation (Table 1).
Orthotics can significantly reduce the deleterious skeletal effects created with each step during walking. At the moment of impact when the heel strikes the ground, a shock wave is propagated through the entire human musculoskeletal system.9 This shock wave passes through the skeleton at more than 200 miles per hour and jolts the base of the brain up to half a millimeter in normal walking.10 This amount of force can cause persistent painful and stiff joints, especially in patients with degenerative changes in the spinal discs and joints.
Orthotics should be considered a necessary component of chiropractic care. DCs who fail to use these effective treatment tools are bound to experience poorer outcomes and less treatment satisfaction. CP
John K. Hyland, DC, DACBR, DABCO, CSCS, consults, advises, and trains on the concepts of spinal rehabilitation. He has also served as director of several chiropractic rehabilitation practices for the past 7 years and works with the US Figure Skating Association. He can be reached at 303-465-9158.
References
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2. Otman S. Energy cost of walking with flat feet. Prosthet and Orthot Intl. 1988;12:73–76.
3. Dananberg HJ, Giuliani M. Chronic low-back pain and its response to custom-made foot orthoses. J Am Podiatr Med Assoc. 1999;89:109–117.
4. Sucher BM, Heath DM. Thoracic outlet syndrome—a myofascial variant: structural and postural considerations. J Am Osteopath Assoc. 1993;93:334–345.
5. Yekutiel MP. The role of vertebral movement in gait: implications for manual therapy. J Man Manip Ther. 1994;2:22–27.
6. Botte RR. An interpretation of the pronation syndrome and foot types of patients with low back pain. J Am Podiatr Assoc. 1981;71:243–253.
7. Hammer WI. Hyperpronation: causes and effects. Chiropractic Sports Medicine. 1992;6:97–101.
8. Giles LGF, Taylor JR. Lumbar spine structural changes associated with leg length inequality. Spine. 1982;7:159–62.
9. Busseuil C. Rearfoot-forefoot orientation and traumatic risk for runners. Foot & Ankle Intl. 1998;19:32–37.
10. Voloshin AS. Shock absorption during running and walking. J Am Pod Med Assoc. 1988;78:295–299.
11. Hartley A. Practical Joint Assessment: A Sports Medicine Manual. St Louis: Mosby YearBook; 1991:571.
12. Schweitzer ME, White LM. Does altered biomechanics cause marrow edema? Radiology. 1996;198:851–853.
13. Beckett ME. Incidence of hyperpronation in the ACL injured knee: clinical perspective. J Athl Train. 1992;27:58–62.
14. Eng JJ, Pierrynowski MR. Evaluation of soft foot orthotics in the treatment of patellofemoral pain syndrome. Phys Ther. 1993;73:62–70.
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