Maintenance of a soft tissue seal around percutaneous devices is challenged by the downgrowth of periprosthetic tissues—a gateway to potential infection. As negative pressure wound therapy (NPWT) is used clinically to facilitate healing of complex soft tissue pathologies, it was hypothesized that NPWT could limit downgrowth of periprosthetic tissues. To test this hypothesis, 20 hairless guinea pigs were randomly assigned into four groups (n = 5/group). Using a One‐Stage (Groups 1 and 3) or a Two‐Stage (Groups 2 and 4) surgical procedure, each animal was implanted with a titanium‐alloy subdermal device porous‐coated with commercially pure, medical grade titanium. Each subdermal device had a smooth titanium‐alloy percutaneous post. The One‐Stage procedure encompassed insertion of a fully assembled device during a single surgery. The Two‐Stage procedure involved the implantation of a subdermal device during the first surgery, and then three weeks later, insertion of a percutaneous post. Groups 1 and 2 served as untreated controls and Groups 3 and 4 received NPWT. Four weeks postimplantation of the post, the devices and surrounding tissues were harvested, and histologically evaluated for downgrowth. Within the untreated control groups, the Two‐Stage surgical procedure significantly decreased downgrowth (p = 0.027) when compared with the One‐Stage procedure. Independent of the surgical procedures performed, NPWT significantly limited downgrowth (p ≤ 0.05) when compared with the untreated controls.

Long-term maintenance of a dermal barrier around a percutaneous prosthetic device remains a common clinical problem. A technique known as Negative Pressure Wound Therapy (NPWT) uses negative pressure to facilitate healing of impaired and complex soft tissue wounds. However, the combination of using negative pressure with percutaneous prosthetic devices has not been investigated. The goal of this study was to develop a methodology to apply negative pressure to the tissues surrounding a percutaneous device in an animal model; no tissue healing outcomes are presented. Specifically, four hairless rats received percutaneous porous coated titanium devices implanted on the dorsum and were bandaged with a semi occlusive film dressing. Two of these animals received NPWT; two animals received no NPWT and served as baseline controls. Over a 28-day period, both the number of dressing changes required between the two groups as well as the pressures were monitored. Negative pressures were successfully applied to the periprosthetic tissues in a clinically relevant range with a manageable number of dressing changes. This study provides a method for establishing, maintaining, and quantifying controlled negative pressures to the tissues surrounding percutaneous devices using a small animal model.

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