EPOS Waterproof by liaoqinmei

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									                                                                                        Buoyancy of Synthetic Casts
                                                                                Twee T. Do, MD; Jose Herrera-Soto, MD; Alvin H. Crawford, MD
                                                                                                     Cincinnati Children’s Hospital Medical Center
                                                                                                                 3333 Burnet Avenue
                                                                                                                Cincinnati, Ohio 45229




Introduction                                        Methods                                                                                                                                            Conclusion
The introduction of waterproof lining has           The cast of a 5 year old was used as a                                                                                                             The results of this preliminary study show
enhanced the quality of life for those treated      template. A set of synthetic and regular                                                                                                           that waterproof synthetic liners are very
with casts. The synthetic material contains         casts were made. All were weighed prior to                                                                                                         buoyant in water. Although the amount of
billions of pores that repel water and              testing. The casts were then tested to failure                                                                                                     weight necessary to sink the test casts in
essentially enhances the body’s natural             (sinking) in the Hubbard tank by sequential                                                                                                        this study was small, the weights consisted
buoyancy when in water. In the older child          addition of lead weights.                                                                                                                          of solid lead pellets which is not the case
or adult where the proportion of the leg is                                                                                                                                                            with a human limb. The enhanced
relatively large compared to the rest of the                                                                                                                                                           buoyancy of a synthetic-lined cast on the
body, this enhanced buoyancy may be an                                                                                                                                                                 lower extremity of a very young child less
advantage. In the child with a smaller limb,                                                                                                                                                           than 5 years of age may pose a potential
however, this enhanced buoyancy may have                                                                                                                                                               danger to that child when immersed in a
potentially devastating risks in the pool. We      Results                                                                                                                                             pool. The initial buoyant force may be too
have had a near drowning complication in a         The regular casts sank immediately after                                                                                                            startling and thus, prevent the child from
young child treated by a waterproof leg cast.      immersion. Time from submersion to                                                     Figure 2. Standard fiberglass cast is then wrapped around,   achieving a vertical position in the water.
This led us to examine the buoyancy of             bottom ground was less than 5 seconds. All                                             allowing fracture control and water-related activities
                                                                                                                                                                                                       This places them in a higher risk for water
synthetic casts, and to determine its criteria     waterproof casts stayed afloat. With                                                                                                                intoxication and/or drowning, especially
use in small children.                             sequential addition of lead weights, the                                                                                                            when not properly supervised.
                                                   casts finally sank at approximately 500
                                                   grams. The casts stayed afloat longer with                                               Table 1. Added lead weight
                                                   more weights in the supine position than the                                             comparisons * Weight added in grams
                                                   standard upright position.
                                                                                                                                          Cast Total          Weight of Fiberglass Lead
Case Report                                                                                                                                    Cast           Liner*               Weight
                                                                                                                                                                        Weight*
A fiberglass cast with waterproof lining was                                                                                                   Weight*                             Added               Acknowledgments
placed on a 5 year old boy weighing 19.4 kg                                                                                                                                        to                  The authors wish to thank Susan L. Foad,
as postoperative immobilization for an injury.                                                                                                                                     Failure*            MPH for poster preparation.
Eleven days later, the patient was found by
                                                                                                                                          1          235      40        195        210
his older sister floating face-down and
unresponsive in his backyard pool. At the                                                                                                 1          235      40        195        210
                                                                                                                                          2          240      25        215        210                 Reference
time of the incident, he had been left at the
pool unsupervised for about 5 minutes                                                                                                     2          240      25        215        225                 Herrera-Soto JA, Do TT, Crawford AH.
without a life vest. By report, the patient was                                                                                                                                                        Buoyancy of synthetic cast and its
                                                                                                                                          3          295      40        255        240
not a good swimmer. In addition, his mother                                                                                                                                                            implications to young patients. J Pediatr
                                                                                                                                          3          295      40        255        240                 Orthop. 2005:25;366-368
had noticed seeing the child's casted Ieg
                                                                                                                                          5          340      40        300        255
floating in the pool. His father (EMS-trained)
resuscitated him with CPR.                                                                                                                5          340      40        300        270
Two weeks after discharge from the                                                                                                        6          340      25        315        210
hospital, the patient was re-evaluated in the                                                                                             6          340      25        315        180
clinic and was doing well. The mother                                                                                                     4          370      40        330        225
reported that she had taken her son, this         Figure 1. Waterproof liners have grooves between the
                                                  bubbles of the liners to allow passage of moisture through the                          4          370      40        330        180
time wearing a life jacket, back into the pool.   cast. At least two layers of liner should be placed.                                    7          215      0         215        0
She noted that again the casted Ieg tended
to float and that it was impossible for the                                                                                               7          215      0         215        0
child to dip that leg into the water.                                                                                                     8          240      0         240        0
                                                                                                                                          8          240      0         240        0
                                                                                                                                          Avg.       292.5    35        262.5      221.3

								
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