Despite many studies on different aspects of transtibial sockets and residual limbs, there is a lack of knowledge to enable consistent manufacturing of a comfortable socket and desirable alignment without the need for several trial and error fittings [11]. The socket is usually made through the process of shape capturing, rectification, and alignment. Before any comparison can be http://www.selleckchem.com/products/tofacitinib-cp-690550.html made, repeatability in the socket shape and volume is the fundamental factor to investigate the effectiveness of socket designs and to understand differences between them.State-of-the-art prosthetic sockets are designed and hand-crafted individually. Depending on the socket concept, a Plaster of Paris (POP) wrap cast is manually applied over the residual limb (residuum) or over the elastomeric liner covering the residual limb with the aim to capture a modified shape of the soft tissues.

Prosthetists shape the POP during casting for the PTB socket using his/her hands (Hands-on) while in the ICECast a pressure bladder is used for this purpose (Hands-off). This shape is used to produce a positive model, which is afterwards adapted (rectified) according to one of the number of design paradigms. These procedures are highly individual, often inconsistent, and based on tacit knowledge. The performance by an individual prosthetist will be strongly influenced by personal experience, skill, and beliefs [12, 13]. When the socket manufacturing process is not reproducible it will, besides the obvious prosthetic fit issues, affect the positioning of the socket relative to the prosthetic foot (alignment) and hence alter ambulation.

Without doubt those difficulties compromise the prosthetic rehabilitation process [13, 14].The shape capturing consistency of Hands-on and Hands-off sockets has been compared using a manikin model [13]. The Hands-off concept showed a constant pattern of maximum radius variation of 1.4mm, whereas the Hands-on concept had maximum radius variations of approximately 2.4mm and 5mm in the distal part and proximal part of the model, respectively. Quantification of inter- and intra-socket shape and volume differences requires accurate alignment of a three-dimensional (3-D) model of the residual limb in a common coordinate system.In surface scanning methods, the morphological information about the bone and its relation to the surface of the socket, which could be useful in better understanding the socket fit, is missing.

The Spiral X-ray Computer Tomography (SXCT), MRI, and Ultrasound provide both internal and external limb information. Therefore, the rigid internal limb structure (e.g., tibia) can be used as a reference to align multiple 3-D models of a residual limb [15, 16]. These methods can also be used to scan the residual limb while the socket/prosthesis is donned. Smith Cilengitide et al.