Chronic wounds that fail to heal over extended periods pose a significant financial burden on the healthcare system, underscoring the urgent need to enhance clinical treatments. Among the most promising approaches are stem cell-based therapies. Substantial evidence suggests that mesenchymal stem cells (MSCs) can facilitate the healing of chronic wounds in both animal models and preclinical studies, primarily through their paracrine actions. The bioactive factors and cytokines secreted by MSCs can be harvested in the form of conditioned medium. This medium has been processed into a lyophilized powder for clinical use. Patients with chronic wounds will recruited and divided into two groups: the control group will receive the commonly used fibroblast growth factor, while the experimental group was treated with the lyophilized powder. The study aims to assess the efficacy and safety of this Stem cell and exosome in treating chronic wounds (especially pilonidal sinus).