SBIR-STTR Award

For centuries, patients with limb amputations have required a prosthetic socket to cover their residuum as a means for attaching the prosthesis to their body. This traditional method constitutes indirect attachment, as an area of soft tissues and skin lies between the prosthesis and the residual bone. In order to eliminate or avoid pain and discomfort associated with indirect attachment, a technology of direct prosthetic attachment called "osseointegration" was introduced in the nineties (Eriksson and Branemark 1994). Despite the relatively successful integration of a titanium implant with the residual bone, the problem of the device-skin interface in the area where the implant goes outside of the residuum remains unsolved. The high risk of infection and secondary trauma precludes the technology of direct skeletal attachment from wide clinical studies and implementation. The proposed study is aimed at developing a new "Residuum-Integration Prosthetic Technology" to be used in limb prosthetics. The technology will include a "Skin and Bone Integrated Pylon" (SBIP), which will connect the residuum with external limb prosthesis. The SBIP will be integrated not only with the residual bone, but also with the residuum's skin in order to minimize the risk of infection and secondary trauma. The investigators will develop an optimal porous titanium matrix and design of the Skin and Bone Integrated Pylon, and also a biological process to maximize the ingrowth of bone and skin cells of the residuum to the SBIP. The mathematical modeling and mechanical testing will be followed by a technological study on the process of manufacturing of the composite porous structure enforced with a permeable internal frame. Inadequate prosthetic rehabilitation after limb amputation is a serious problem relevant to public health. The public value of solving this serious problem is much more elevated when a country is at war. Providing US Veterans with infection-safe direct skeletal attachment of prostheses will improve the quality of their lives and eliminate the costs associated with the multiple fabrications and adjustments of the prosthetic sockets.

The Phase I study "Manufacturing technology for skin integrated composite prosthetic pylon" demonstrated feasibility of the novel "Residuum-Integration Prosthetic Technology" to be used in limb prosthetics. The technology includes a "Skin and Bone Integrated Pylon" (SBIP), which connects the residuum with an external limb prosthesis. As histopathology analysis has demonstrated, the SBIP will be integrated not only with the residual bone, but also with the residuum's skin in order to minimize the risk of infection and secondary trauma. During the proposed Phase II study the investigators will develop an optimal porous titanium matrix and design of the Skin and Bone Integrated Pylon to maximize the ingrowth of bone and skin cells of the residuum to the SBIP. The mathematical modeling and mechanical testing will be followed by a technological study on the process of manufacturing of the composite porous structure enforced with a permeable internal frame. A pre-clinical study with rodent and non-rodent animals will be conducted to verify the scientific hypotheses and to select the optimal design of the SBIP.

Public Health Relevance:
Inadequate prosthetic rehabilitation after limb amputation is a serious problem relevant to public health. The public value of solving this serious problem is much more elevated when a country is at war. Providing US Veterans with infection-safe direct skeletal attachment of prostheses will improve the quality of their lives and eliminate the costs associated with the multiple fabrications and adjustments of the prosthetic sockets.

Public Health Relevance Statement:
Inadequate prosthetic rehabilitation after limb amputation is a serious problem relevant to public health. The public value of solving this serious problem is much more elevated when a country is at war. Providing US Veterans with infection-safe direct skeletal attachment of prostheses will improve the quality of their lives and eliminate the costs assosciated with the multiple fabrications and adjustments of the prosthetic sockets.

NIH Spending Category:
Assistive Technology; Bioengineering; Rehabilitation

Project Terms:
Afghanistan; American; Amputation; Amputees; Animals; Artificial Limbs; Bone; Bone and Bones; Bones and Bone Tissue; Cells; Characteristics; Clinical Protocols; Clinical Trials, Phase I; Clinical Trials, Phase II; Country; Development; Devices; Early-Stage Clinical Trials; Extremities; Extremities, Artificial; Fatigue; Finite Element Analyses; Finite Element Analysis; Histopathology; INFLM; Infection; Inflammation; Investigators; Iraq; Lack of Energy; Life; Limb Prosthesis; Limb structure; Limbs; Mammals, Rodents; Math Models; Mechanics; Medical Device; Methods and Techniques; Methods, Other; Modeling; Non-Trunk; Phase; Phase 1 Clinical Trials; Phase 2 Clinical Trials; Phase I Clinical Trials; Phase I Study; Phase II Clinical Trials; Porosity; Progress Reports; Prosthesis; Prosthetic device; Prosthetic rehabilitation; Prosthetics; Public Health; Reports, Progress; Research Personnel; Researchers; Residual; Residual state; Resistance; Risk; Rodent; Rodentia; Rodentias; Safety; Skin; Sound; Sound - physical agent; Structure; Techniques; Technology; Testing; Ti element; Titanium; Trauma; Veterans; War; animal efficacy; bone; bone cell; cost; design; designing; improved; innovate; innovation; innovative; manufacturing process; mathematical model; mathematical modeling; meetings; novel; particle; phase 1 study; phase 1 trial; phase 2 study; phase 2 trial; phase I trial; phase II trial; preclinical safety; preclinical study; protocol, phase I; protocol, phase II; prototype; public health medicine (field); public health relevance; resistant; secondary infection; skeletal; sound; study, phase II