A Case Study: Functional Positioning Toe Restoration
Robert D. Young, B.S.Ed., C.P. *
The case presented involved a patient with a proximal phalanx resection of the second toe. The great toe and third toe worked under the residual toe and forced it dorsally into contact with the shoe. This toe is 3/4" short and is not muscularly controlled. Lengthening the toe, as well as holding it in position between the great and third toes, were requirements of the restoration.
Dow Corning #382 Medical Elastomer® (Fig. 1 ) was the material used for this prosthesis, using conventional pigments to color the material. This material offers a soft, resilient, cosmetically acceptable prosthesis, which holds on by suction and a "ridge" fit to the plantar toe spaces.
Fabrication began with an alginate impression of the distal portion of the foot. A piece of tongue depressor was cut to hold the great and third toes apart enough to allow the alginate to completely encompass the residual toe. A piece of tape was used between the toe and tongue depressor to hold the toe in its proper location. A positive mold was then prepared and modified. Modification included reducing the circumference of the positive mold of the residual toe, to offer a snug fit in the socket portion, and filling in the spaces between the other toes, leaving a ridge on the plantar surface to locate and stabilize the prosthesis (Fig. 2 and Fig. 3 ). The plaster positive was then dried and coated with a plastic parting lacquer.
A two piece mold was created over the plaster positive model, separating at the peak width around the entire model. Nails inserted in the base of the mold were used to key in the upper and lower portions of the mold when it was poured and for later reassembly (Fig. 4 and Fig. 5 ). Enough material was then carved out of the two piece mold sections to restore the toe length, encompass the residual toe, add toenail detail (Fig. 6 ), and provide a plantar surface stabilization wing extending from the peak of the plantar toe pads to a very thin edge following the midline of the metatarsal heads (Fig. 7 ).
A sprue hole was drilled at the distal plantar portion of the prosthetic cavity, and a riser hole was provided at a location away from any area of importance. Dow Corning Elastomer® was poured into the halves of the mold and the plaster positive inserted. The mold was then put together and secured with an elastic wrap.
The mold was set with the sprue hole uppermost to allow any bubbles to work their way out. Extra material was added, as the level reduced in the sprue, until the cavity was completely full. Two prostheses of slightly different colors were made, and the one that best matched the patient's skin tone was provided to the patient (Fig. 8 and Fig. 9 ).
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