Early response to autologous concentrated growth factor fibrin membrane coverage in limb wounds: predictors from the Bates–Jensen Wound Assessment Tool

Limb wounds remain difficult to treat; concentrated growth factor (CGF) is an autologous platelet-derived adjunct that has been used in wound care. A retrospective analysis was conducted on data from 48 patients with limb wounds treated at the Department of Microsurgery of hand and foot, People’s Hospital of Qianxinan Prefecture, between June 2019 and July 2022. Patients received CGF fibrin membrane coverage in addition to routine debridement and dressing changes. Patients were categorized as responders or non-responders using a prespecified operational threshold of ≥ 20% wound-area reduction at 1 week. Baseline characteristics and BWAT scores were compared between groups. Logistic regression, receiver operating characteristic analysis, calibration assessment, and bootstrap internal validation were performed to explore the prognostic performance of baseline BWAT score and wound area. Available follow-up outcomes were updated by telephone during the revision period, at least 2 years after the initial CGF application, and were summarized descriptively. Thirty-four patients met the prespecified definition of an early response, whereas 14 were classified as non-responders. Responders had greater reductions in BWAT scores and were less likely to have chronic wounds or tendon/bone exposure than non-responders (all P < 0.05). Baseline BWAT score was associated with early response (OR = 0.713), with an apparent AUC of 0.868 (95% CI 0.766–0.970) and an optimism-corrected AUC of 0.868. After ln(baseline wound area) was added, the apparent AUC was 0.922 (95% CI 0.846–0.998), and the optimism-corrected AUC was 0.909. Telephone follow-up information was available for 46 patients at least 2 years after the initial CGF application. Among them, 37 achieved complete wound healing without further reconstructive surgery. The available functional and symptom outcomes were qualitative and non-standardized. Among patients receiving standard wound care combined with CGF fibrin membrane application, lower baseline BWAT scores and smaller wound areas were associated with a more favorable operationally defined early response at 1 week. Baseline BWAT score, alone or combined with wound area, may support exploratory risk stratification; however, external validation and confirmation in larger prospective cohorts are required before clinical implementation.