Study to Determine if Different Prosthetic Sockets Effect How Much Oxygen is in the Tissue of Lower Limb Amputees While They Are Walking
Condition: Amputation; Diabetes Complications; Leg Injuries; Traumatic Amputation
MeSH terms: Diabetes Complications; Amputation, Traumatic; Leg Injuries
Study type: Interventional

Summary: 
      Amputee gait produces periodic occlusion of residual limb blood vessels. During the stance
      phase of gait, body weight cause the prosthesis to compresses the soft tissue of the residual
      limb and occlude blood flow. This occlusion can be relieved during swing phase, but may
      depend on type of prosthesis. The purpose of the proposed research is to: (1) discover the
      range of tissue oxygenation in the intact and residual lower limbs of dysvascular amputees
      during gait and (2) to learn which of five different prosthetic limb systems provides greater
      tissue oxygenation.
    

Detailed description: 
      The amount of oxygen in residual limb tissue is an important health status indicator;
      resistance to infection, promotion of wound healing, production of collagen, and
      epithelialization all correlate with higher oxygen levels. Unfortunately, simply donning a
      lower limb prosthesis may limit circulation and reduce the level of tissue oxygenation. This
      reduction may be compounded by the biomechanical forces of gait. The compressive loads of the
      body's weight during stance and the inertial loads of the prosthesis during swing may further
      occlude circulation, albeit by different mechanisms.

      For the dysvascular lower limb amputee, the choice of prosthetic socket and suspension system
      may impact the overall health of their residual limb and wound healing capacity. An
      inappropriate choice may lead to skin irritation, tissue breakdown, discomfort, and reduced
      mobility. For these patients, any component that reduces tissue oxygenation is a significant
      problem because compromised circulation can forestall wound healing.

      The objective of the proposed research is to use photo-oximetry to discover which of five
      different prosthetic limb systems results in higher residual limb tissue oxygenation during
      both rest and gait. This experiment will enable evidence-based decision making on this
      clinically relevant problem. Using a prospective, randomized cross-over experimental design
      and the investigators' photo-oximetry system, the investigators will measure and compare the
      tissue oxygenation along the medial and lateral surfaces (3 sites each) of the residual limb
      during rest and walking.
    

Intervention name(s): Pe-Lite and sleeve suspension socket; Total Surface bearing a socket with a sleeve suspension but without suction; Total surface bearing suction socket with a pin lock suspension; Total surface bearing suction socket with a sleeve suspension; Vacuum-assisted socket system (Harmony System, Otto Bock)
Intervention type(s): Device; Device; Device; Device; Device
Intervention description(s): Prosthetic socket worn by the amputee that has a Pe-lite foam liner between the socket and the residual limb. It is suspended from the residual limb using a sleeve at the top of the socket.; Prosthetic socket worn by the amputee where the fit of the socket touches every part of the residual limb. This socket is suspended from the residual limb using a sleeve at the top of the socket.; Prosthetic socket worn by the amputee where the fit of the socket touches every part of the residual limb. This socket is suspended from the residual limb using a pin that protrudes from the bottom of the liner into the socket that is then locked in place by the amputee.; Prosthetic socket worn by the amputee where the fit of the socket touches every part of the residual limb. This socket using vacuum suction plus a sleeve at the top of the prosthetic socket to enhance the security of the suspension.; Prosthetic socket worn by the amputee where the a vacuum pump, in this case a mechanically-activated pump, creates a vacuum between the socket and the limb. This vacuum suspends the prosthetic limb from the amputee's residual limb.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Artificial limbs; Gait; Oximetry; Prosthesis; Rehabilitation