Weinstein Lovell and Winters Pediatric Orthopaedics 7e

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CHAPTER 30  |  The Child with a Limb Deficiency

the SCSP design, except the anterior proximal brim does not enclose the patella, and therefore allows greater freedom and range of motion. Contraindications for both the SCSP and SC design include obese or muscular limbs and patients with heavy scarring around the knee. SC cuff suspension is a common form of suspension for the pediatric transtibial amputee (Fig. 30-48D). The cuff is fabricated from leather and encompasses the femoral condyles and patella. It is attached to the medial and ­lateral aspects of the socket. The neoprene sleeve suspension is another useful suspension in the pediatric prosthesis (Fig. 30-48E). For the very active child, it provides a great level of security in that the prosthesis will not come off. Recent advances in silicone and urethane technology have increased comfort, flexibility, and cosmesis of the sleeve suspension systems. Silicone suspension liners have become increasingly popular as a method of suspension without the need for belts or cuffs (Fig. 30-49). The liner is rolled onto the resid- ual limb. At the distal end of the liner is a serrated pin. Inside the distal end of the socket is a shuttle or receptacle mechanism. Once the liner is donned, the amputee places the limb in the socket, and the pin and shuttle engage and lock into place. Pressing of a button hidden on the medial distal aspect of the prosthesis releases the pin, and the

­residual limb can be removed from the socket. Because of the physical characteristics of the liner, the greater the dis- tracting forces placed on the prosthesis, the tighter the liner grips the residual limb. This system is used extensively in young children. Where space is at a premium, a cushioned silicone liner used in conjunction with a socket expulsion valve and a silicone sleeve allows the amputee to achieve a remarkable level of suspension using a modified suction technique. Ankle Disarticulation Prosthesis (Syme).  The obtura- tor (medial opening) design is most often used when the ­distal bulbous end is large and the medial malleolus is prominent (Fig. 30-50A). The removable or segmented liner socket incor- porates a full foam liner that has been built up to the same cir- cumference as the distal bulbous end. A laminated shell is then formed over this insert. The patient dons the liner first, then slips this into the laminated receptacle (Fig. 30-50B). An atro- phied residual limb with a small heel pad is best suited for this design, and the degree of cosmetic restoration will be very good. The silicone or bladder prosthesis utilizes an inner elastic area that stretches to permit the passage of the bulbous end of the residuum through the narrower circumference of the tibia and fibula, then constricts once the distal end has passed through

FIGURE 30-49.  Silicone suspension liners (Triple S socket) have become very popular. The soft silicone liner has a serrated pin incorporated into the bottom of the liner. The patient rolls the liner on the residual limb (A) , then inserts the limb into the prosthesis (B) . At the bottom of the prosthesis is a socket in which the pin locks. It is released by pushing the button on the medial side of the prosthesis.

A

B