Autologous Volar Fibroblast Injection Into the Stump Site of Amputees

This study is a clinical trial testing the safety and efficacy of volar fibroblast (skin cells from the palm or sole) injections for thickening the epidermal (skin) layer at the stump site in people with below the knee amputations. The study will enroll adults seen at Johns Hopkins. The investigators have demonstrated that injection of fibroblasts (from the palm or sole) is safe in healthy adults and potentially enhances palm or sole features in skin cells in areas other than the palm and sole. In a prior study, healthy adults injected with fibroblasts (from the palm or sole) experienced more firm skin at the injection site. The objective of this study is to determine if fibroblast (from palm or sole) injections are safe and effective at increasing epidermal thickness and skin firmness at the stump site in below the knee amputees. Outcomes are assessed via questionnaires, non-invasive imaging devices, and non-invasive skin firmness measuring devices. Injections will be targeted to the entire stump (unless determined otherwise by the PI and participant), including pressure intolerant areas of the skin that come into contact with the prosthetic socket, a region that is prone to skin irritation and breakdown, We will evaluate the most effective approach to administering this intervention via injections to the entire stump and the safety and effectiveness of whole stump injections and their effects on prosthesis use, skin breakdown, quality of life, and activity level. The investigators hope that information from this study will help with problems like skin breakdown in patients with amputations and prosthetics. The skin at the stump was not meant to withstand the pressure and friction of prosthetics and this study is the first step in trying to convert stump skin to palm/sole-like skin.