CLINICAL AND AESTHETIC CONSIDERATIONS IN THE DEVELOPMENT AND FITTING OF A CUSTOMISED HAND AND FINGER PROSTHESIS

Abstract

A double-layered moulding technique incorporating a colour matching procedure for producing custom-made linger and hand prostheses has been successfully developed. The technique is based on the multiplier anatomy, pattern of pigmentation, and optical characteristics of the human skin. With the technique, the prosthesis is moulded in an outer and an inner layer of silicone rubber tinted intrinsically, incorporating an extrinsic touch-up colouration "sandwiched" between the layers capable of reproducing the aesthetic colouration and life-like appearance of the skin. To achieve a close match lo the remaining parts of the mutilated hand in terms of size, shape, and surface details, and help enhance acceptance, finger prostheses were custom-moulded from an impression taken from the corresponding digit on the patient's contralateral hand, while hand prostheses were made from an impression of the corresponding hand or a sibling, if not, a close acquaintance. The problems related to moulding of the prostheses were discussed and the appropriate solutions recommended. In Section I of the experimental work, six sample prostheses (Gp1-Gp6) moulded in variations of the double-layered design were investigated to identify the prosthesis which best reproduces the aesthetic colouration and life-like appearance of the skin. The parameters studied were the colour and opacity or the outer and inner layers, in addition to the effects or touch-up colouration "sandwiched" between the layers. Assessment of the sample prostheses by individuals (n=76) from six cohorts or vocation demonstrated significant differences in their aesthetic quality, with Gp1 shown to be superior to all groups. Models or optics were proposed to help account for the differences in the visual perception or their aesthetic effects. In Section II, a total or 109 patients sustaining various forms of ringer and hand amputations were filled with prostheses based on Gp3 design. The immediate post-filling results were evaluated with special emphasis on aesthetic appearance. The aesthetic considerations in the fitting of these prostheses were discussed. The positive response or the patients in the evaluation demonstrated the success or the custom prostheses in the aesthetic restoration or ringer and hand amputations.