In the early to mid-1970s one commercial entity began to teach that the cephalad margin of scoliosis corrective/holding pads should be no more cephalad than the apex of the curve they were applied to. In the years since, that “rule” has gained considerable inertia, as it has been consistently part of teaching hundreds of orthotists how to treat scoliosis. The rule has been adhered to quite widely, but I’m not aware that it has the support of either clinical trials or mathematical model analysis. My own clinical experience, qualitative engineering analysis, and
literature search indicated early on that such a rule was unwise. In fact, I feel that such a thoracic pad placement formula is clearly detrimental for some double curve (for example, right thoracic-left lumbar) combinations and for thoraco-lumbar curves. The biomechanics reasoning (with illustrative 3-D models) for this view was presented at the scoliosis symposium in Portland, Oregon. My own analysis indicates that thoracic pads should be centered at a level horizontal to the curve apex in most cases.
Unilateral Cervical Component for AIS Orthoses
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Postero-lateral view of Tamarack’s custom cervical component on a CTLSO. The stainless steel bar is welded to the superstructure posteriorly and coupled to the anterior bar by a vertical axis hinge. |
At the same time as the Milwaukee has been
recognized as the “gold standard” for treating adolescent
idiopathic scoliosis (AIS) and as being the most adaptable (for
managing sagittal abnormalities which often attend AIS) and
adjustable design, orthopedists and orthotists have turned to
alternatives. The reason is the neck ring, which has always been
considered a very significant factor limiting acceptance of the
Milwaukee orthosis.
In the early 90’s Tamarack designed and built a substitute for
the Milwaukee neck ring. Our reasoning was that a unilateral (left
or right) cervical component of the correct design could perform
both of the very important functions of the old-style neck ring: 1)
The anterior-posterior mechanical linkage at the cephalad extremity
of the orthosis greatly increases the structural integrity and pad
placement options; 2) It serves as an alignment stimulus on the
left (usually) or right side of the child’s neck, depending on the
curve pattern.
We reasoned that eliminating neck encirclement would be a
significant step toward greater emotional-psychological and
cosmetic acceptance for both parents and child. The Tamarack
cervical component is made of metal to minimize bulk while
maintaining excellent mechanical linkage integrity (rigidity).
Marty Carlson, CPO, FAAOP, has a masters degree in engineering mechanics and materials from the University of Minnesota and received his orthotic and prosthetic education at Northwestern University. He was director of habilitation technology at Gillette C