Scoliosis has recently been associated with a lower quality of life [30
], lower scores on the SF-36 health questionnaire [33
], and makes patients prone to developing chronic pain more often than the general population [34
]. Therefore, reducing scoliotic curvatures, even in the absence of symptoms, seems to be a worthy outcome objective for clinical practice. This opinion is further supported by recent evidence of the deleterious effects of abnormal spinal loading [35
]. Given that the average curvature progression in idiopathic scoliosis is 7.03° per year [38
], the traditional method of regular observation without treatment seems to be reactionary rather than corrective or preventive.
Spinal manipulation alone does not appear to significantly alter spinal structure when administered as a sole treatment modality [39
]. Therefore, in the instance of scoliosis, treatment should include the use of both manipulative and rehabilitative procedures, so that structural changes can be attempted. It is important to stress that spinal manipulation was avoided, when possible, in the present study. Unpublished clinical observation by the authors has shown that over-manipulating or adjusting the spine seems to create a certain amount of instability, possibly leading to further buckling of the scoliotic curvature. The significance of home care to the results was not reported here. It is unknown how the omission of home care would have affected the outcome measurements, given that 3 subjects were dropped from the study for noncompliance in performing home care. Future research should account for this potential variable to determine its necessity and relevance.
The outcome measures for this study are divided into a series of both short-term and long-term goals. The outcome of the initial stage of care is to reduce forward head posture and improve the sagittal cervical and lumbar curves. As the position of the head migrates forward, or away from the body's vertical axis, increased strain is placed upon the muscles of the head, neck and shoulders. Cailliet and Zohn indicated that an additional 10 inch/lbs of leverage is added to the spinal system in a forward head posture [41
]. Additionally, this added leverage causes increased isometric contraction of various spinal muscles, such as the splenius capitis, trapezius, SCM, and levator scapula. Sjogaard et al [43
] reported that blood flow through a given muscle is decreased as a muscles contraction increases, being virtually cut off at 50–60% contraction. The resultant lack of blood flow forces the muscle to rely on anaerobic metabolism. As anaerobic metabolism progresses, metabolites such as substance P, bradykinin, and histamine build up and excite chemosensitive pain receptors, causing a barrage of nociceptive afferent input [44
], resulting in dysafferentation [45
]. Being that postural control is largely dependant upon cervical joint mechanoreceptors and afferent input from ligament and musculotendinous sources [46
], correcting the postural distortions responsible for this pathophysiologic process may be beneficial in patient populations, such as scoliosis, where postural control is significantly altered [48
The effects of the loss of cervical and lumbar lordosis have been previously reported [19
]. Rhee et al [49
] noted that correction of the sagittal curves might be related to the long-term health of the spine in scoliosis management. Harrison et al [35
] illustrated how a loss of the sagittal curve alters the mechanical properties of the spinal cord and nerve roots, which may change the firing patterns of involved neurons. Schafer illustrated how an increased demand is placed upon the cervical musculature when the cervical curve is straightened or reversed [50
]. It is important that the cervical spine be in a normal structural alignment. A loss of the cervical lordosis and concomitant forward head posture may elicit the pelvo-ocular reflex, which causes an anterior pelvic translation to balance the head's center of gravity [51
]. Wu et al [52
] point out that in postural control, preference is given to the position of the head, neck, and trunk. Therefore, correction of the cervical spine becomes imperative so that the rest of the spine can be rehabilitated in relation to a normal reference point in space.
Once the cervical and lumbar lordoses are corrected, coronal reduction of the scoliotic curvatures begins. Here this was accomplished by adding a shoulderweight to the right shoulder and a hipweight to the anterior right ilium and posterior left ilium. Wu and Essien [53
] have previously reported the effects of adding external weight to the upper body via a shoulder weight. They identified predictable patterns in which the trunk would compensate for the amount and position of the weight. Wu and MacLeod [52
] identified a shift in the center of mass toward the added weight when placed on the side of the pelvis. However, the trunk and head remained in the same position, while the pelvis and lower extremities shifted to counteract the weight while supporting the head and trunk [52
]. In this protocol, we created an environment where external weight was added to the head, shoulder, and pelvic regions simultaneously. Knowing the predictable patterns of compensatory shifting to an altered center of gravity, we placed the headweight, shoulderweight, and hipweights in areas designed to reduce each patient's specific spinal distortion patterns.
Learning a new motor coordination skill can be divided into 3 phases: cognitive, associative, and autonomous [54
]. In the cognitive phase, the patient performs the motor task repetitively to learn until the task requirements are understood. As the patient progresses through the associative and autonomous phases, the task becomes easier to perform, and may ultimately be performed in a variety of practical contexts with decreased repetitions [54
]. While Lantz et al [2
] have shown that chiropractic management, consisting of a combination of manipulative procedures, electric stimulation, and orthotic inserts did not significantly reduce a scoliosis, this treatment does not incorporate these physiotherapeutic procedures. Instead, this treatment requires the use of specific rehabilitative equipment that theoretically recruits the use of head, neck, trunk, and extremity postural reflexes to create specific adaptation to an altered center of gravity and field of gaze.
The study design used here does present specific limitations. Due to the lack of a control group, comparative data and conclusions cannot be made. Additionally, a retrospective design does not blind the practitioners to treatment. Although we attempted to select patient files at random from 3 separate spine clinics, nonrandomized sample populations such as ours do not necessarily reflect the potential outcomes in a general population. Therefore, future studies in this area should incorporate a control group and a randomized patient population. Follow-up studies should also focus on the potential long-term benefits of conservative scoliosis treatment, given the relative scarcity of biomedical literature available on long-term benefits from any scoliosis treatment.