A common cause of lateral deviation of the spine (scoliosis) is easily treated by doctors of chiropractic, but can also be missed and misunderstood. Since other types of scoliosis are more worrisome and have a greater tendency to progress, the more common (and easily corrected) causes of spinal curvatures are often overlooked. This can leave a patient with persisting postural distortions, and recurring subluxations. With a few tests during the clinical examination, many of the scolioses seen in children and adults can be correctly identified and then effectively managed with chiropractic care.
Scoliosis Definitions
The term scoliosis describes “any lateral deviation of the spine from the mid-sagittal plane.”1 There are many possible causes of a lateral curvature, and this condition can affect the cervical, thoracic, or lumbar regions. The most common types of scoliosis seen by doctors of chiropractic can be divided into structural and functional categories.
1. Structural Scoliosis: When a lateral deviation of the spine is fixed, and doesn’t correct during lateral bending, it is termed a structural scoliosis. While there are many disorders that can cause this condition, those most commonly seen are congenital (due to bony anomalies), neuromuscular (associated with various neuropathic and myopathic diseases), and idiopathic (where the underlying cause is unknown). Unfortunately, most of these spinal curvatures do not respond well to conservative care and often require a surgical consultation.
2. Functional Scoliosis: The classification of functional scoliosis has been nicely summarized by Panzer as compensatory (due to leg length inequality or pelvic unleveling), postural (caused by habits and muscle imbalance), and transient (often an antalgic response to a disc herniation).2 The key factor in all of these conditions is the reversibility of the abnormal curvature with various positions and movements. In fact, this is the main method used to differentiate between structural and functional types of scoliosis.
Scoliosis Evaluation
Adams Forward Bending Position: The quickest way to evaluate for a functional scoliosis is to have the patient perform Adam’s position. In this test, the patient flexes forward from the waist, with the arms hanging down and the hands together. If the spinal curvature straightens out and there is no evidence of rib humping, then the test is negative, which indicates a functional scoliosis.3 In addition, a functional scoliosis will disappear when the patient is lying on the table, since the muscles relax and the spine no longer depends on the lower extremities and pelvis for support. This phenomenon is most obvious in younger patients, since the spine becomes less flexible with age, and functional curves become stiffer and more fixed.
Postural Assessment: The first step in examining a patient with a scoliosis is to carefully inspect the alignment of the entire body during relaxed, upright stance. Head position in relation to the body, relative heights of the shoulders and pelvis, and any spinal list or rotations should be noted, since corrective exercises may be needed. The lower extremities must also be evaluated for asymmetry, since functional scolioses are frequently associated with leg length inequality.4 Most commonly seen is excessive pronation of one or both of the feet.
Hyperpronation: The loss of arch height that occurs with excessive pronation allows the pelvis to drop to the more pronated side during stance and gait.5 The resulting lateral pelvic tilt lowers the sacral base and drops the lowest freely-moveable vertebra to the side of the shorter leg. A lateral spinal curvature develops in the lumbar spine due to lack of balanced support from the lower extremities with every step. In response, various compensatory pelvic lists and sacroiliac subluxation complexes have been found to develop.6 Researchers have also verified that a posterior rotation of the innominate bone often develops on the side of a longer leg.7 If the functional curvature progresses to involve the thoracic region, it may demonstrate a mild rib hump, which disappears upon correction of the leg discrepancy.8
Corrective Procedures
Lower Extremity Support: A functional scoliosis with a discrepancy in the length of the legs due to a low medial arch and excessive pronation is easily treated with the use of custom-made stabilizing orthotics to reduce pronation. This provides substantial correction for most short legs, and often avoids the need for a heel lift. In a small percent of patients , a permanent heel lift will be needed, due to an anatomical difference in growth of the legs.
Muscle Imbalances: A functional scoliosis often causes chronic muscular strain, most commonly seen as myofascial trigger points in the quadratus lumborum, but also in the psoas and external abdominal oblique muscles.9 Therefore, manual muscle treatments, stretching and even spinal strengthening exercises may be necessary to obtain rapid and complete resolution of symptoms. These muscle imbalances can become perpetuating factors if the underlying foot and leg asymmetries are not corrected.
Spinal Adjustments: It is very important to assess and adjust the pelvis and spine as each patient adapts to wearing the corrective orthotics. Since excessive pronation places abnormal stress in predictable areas (primarily the sacroiliac joints and lumbar vertebrae), close evaluation of these regions is warranted. And because functional scoliosis interferes with postural alignment generally, the entire spine must be checked and adjusted frequently during the initial adaptation period. In fact, the upper cervical region is often quite slow in adapting to the change in spinal and pelvic posture, and needs to be evaluated regularly and adjusted as needed.
Conclusion
When a lateral curvature of the spine has been found that reduces during forward bending, a functional scoliosis has been identified, and conservative treatment is indicated. A careful postural evaluation will usually discover an asymmetry in the lower extremities, with poor support for the pelvis. The combination of custom-made orthotic stabilizer support and chiropractic adjustments is often very effective in treating these functional scolioses, much to the relief of the patient and concerned family members.
A 1980 graduate of Logan College of Chiropractic, Dr. John Hyland has practiced for more than twenty years in Colorado. In addition to his specialty board certifications in chiropractic orthopedics (DABCO) and radiology (DACBR), Dr. Hyland is nationally certified as a strength and conditioning specialist (CSCS) and a health education specialist (CHES). He now consults chiropractors in the concepts and procedures of spinal rehabilitation and wellness exercise.
References
1. Yochum TR, Rowe LJ. Essentials of Skeletal Radiology. 3rd ed. Baltimore: Lippincott Williams & Wilkins; 2005 p. 405.
2. Panzer DM, Gatterman MI, Hyland J. Postural Complex. In: Gatterman MI, ed. Baltimore: Lippincott Williams & Wilkins; 2004 p. 312.
3. Evans RC. Illustrated Essentials in Orthopedic Physical Assessment. St. Louis: Mosby-Yearbook; 1994 p. 219.
4. Plaugher G. Textbook of Clinical Chiropractic: a specific biomechanical approach. Baltimore: Williams & Wilkins; 1993 p.266.
5. Hammer WI. Hyperpronation: causes and effects. Chiro Sports Med 1992; 6:97-101.
6. Rothbart BA, Estabrook L. Excessive pronation: a major biomechanical determinant in the development of chondromalacia and pelvic lists. J Manip Physiol Therap 1988; 11:373-9.
7. Cummings G, Scholz JP, Barnes K. The effect of imposed leg length difference on pelvic bone symmetry. Spine 1993; 18:368-73.
8. Magee DJ. Orthopedic physical assessment. Philadelphia: WB Saunders; 1987 p.397.
9. Travell JG, Simons DG. Myofascial pain and dysfunction: the lower extremities. Baltimore: Williams & Wilkins; 1992 p.63.