The long-arm caliber is a tool derived from the orthopedic technician laboratory, where it is used to release orthoses for the trunk and limbs.
With the addition of a sliding ring, where a plumb line is attached to, the caliber makes it possible the description of asymmetries of the trunk and decompensations on the frontal plane in numerical terms, therefore repeatable and comparable.
Dimensions: 60 x 23 x 3.5 h cm; Weight: 5.3 kg
A REVISITED TOOL FOR ASYMMETRIES MEASUREMENT
If we only think of a case of lumbar scoliosis and try to describe the hips asymmetry in a report, we find ourselves in using more or less vague terms such as “moderate, evident, remarkable”, certainly not wrong but of little use for comparison.
In the context of a visit for the spine the caliber allows us to quantify the alignment asymmetries on the frontal plane and in particular to evaluate the movement of the head, of the upper trunk part or hips, with respect to the midline, taking for this purpose the inter-gluteal line or alternatively the bisector of the base.
A lateral shift of the midline of the head it’s described by the term decompensation, a shift of the median line of the shoulders or hips is described as front, right or left translation respectively. This shift can be indicated in absolute values (cm) or better in percentage (% of translation) suggestable modality in progress for anthropometric changes affecting the trunk.
To facilitate the calculation
To facilitate the calculation of the translation percentage it’s available a simple two-entry chart along with the instrument. This tells us with a single number how much, in percentage, the center of the measured segment is displaced laterally than the theoretical center of symmetry. The formula used is the following: a-b / a + b%, where as numerator appears hence the difference of the two segments defined on the instrument by plumb line, as denominator the sum of the same segments.
N° Package | Package type | Dimension | Weight | Volume |
---|---|---|---|---|
1 | SCATOLA | cm 74 x 33 x 9 h | kg 1.4 | mc 0.021978 |