Tubular, bifurcated structure knitting

This is the undisputed material of choice for the replacement of medium- and large-diameter arteries. The prostheses are available in straight and bifurcated designs (Fig. 15.7). In fact the technology associated with the design and fabrication of arterial prostheses has spread across the world over the past 40 years. So it is fair to say that these woven (Fig. 15.8) and knitted (Fig. 15.9) tubular structures are now a mature medical product. 

Both weft and warp knitting machines are able to construct tubular structures. Although circular weft knitting machines can only be used in producing single tubes, flat weft knitting machines with two needle beds and double-needle bar Raschel machines are able to produce single, bifurcated and multibranched tubes. 

Figure 6.11 A schematic illustration of a warp-knitted bifurcated tubular structure.

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