Osseointegrated Transcutaneous Device for Amputees: A Pilot Large Animal Model

Area of Science:

• Biomedical Engineering
• Orthopedic Surgery
• Biomaterials Science

Background:

• Traditional above-the-knee amputation prosthetics present challenges like skin issues, discomfort, and increased ambulation effort.
• Osseointegrated implants offer a potential solution by directly integrating with bone, bypassing the stump-socket interface.

Purpose of the Study:

• To evaluate a novel osseointegrated transcutaneous implant using Compress® technology in a large animal model.
• To assess bone-implant osseointegration and identify potential complications associated with different implant lengths.

Main Methods:

• Four Dorset sheep received two-stage surgery for forelimb osseointegrated transcutaneous implants of varying lengths (90mm vs. 46mm).
• Radiographic and histological analyses were performed 16 weeks post-surgery to evaluate osseointegration and complications.
• The study assessed implant stability, infection, and transcutaneous adapter function.

Main Results:

• No fractures occurred in the shorter (46mm) implant group, while the longer (90mm) implant group experienced periprosthetic fractures.
• Histological analysis demonstrated bone-implant osseointegration in two of three examined limbs.
• No histological evidence of infection or transcutaneous adapter failure was observed.

Conclusions:

• The novel osseointegrated transcutaneous implant, particularly the shorter version, shows potential for successful bone integration with minimal complications.
• Compress® technology offers a viable platform for developing endo-exo devices, potentially improving outcomes for amputees.
• Further investigation is warranted to validate these findings in larger studies.