Objective:To investigate the clinical effect of autologous fat transplantation combined with hair transplantation in the treatment of hard and/or thin scalp flat scar after burn.Methods:The clinical data of patients with hard and thin scalp scar after burn admitted to the Department of Plastic Surgery of Peking University Third Hospital from January 2017 to December 2022 were retrospectively analyzed. Fat was extracted from the lower abdomen or outer thigh during the operation, and then injected into the scalp scar after standing for 15 minutes, about 0.8 ml/cm 2 under the hard and/or thin scar area, and 0.2-0.4 ml/cm 2 under the thick and soft scar area. Three months after fat transplantation, hair transplantation was performed in the scar bald area, and the transplant density was 25-35 follicular units (FUs)/cm 2 in the hard and thin scar area, and 30-40 FUs /cm 2 in the thick and soft scar area. The Vancouver scar scale (VSS) was used by two third party plastic surgeons to score the hard and/or thin scar areas of the scalp before and 3 months after scalp fat transplantation. The VSS score was expressed as M ( Q1, Q3), and the preoperative and postoperative data were compared by paired sample Wilcoxon signed rank test. During hair transplantation, the density of implanted hair in the hard and/or thin scar area were recorded. The density of living hair at these sites was measured at the last follow-up, and then the survival rate of hair (living hair density/implant hair density ×100%) was calculated. A third party plastic surgeon evaluated the extent to which scalp scars in the hair transplant area were covered, including completely covered, basically covered, partially covered. Patients’ evaluation with the surgical result was divided into very satisfied, satisfied and dissatisfied. Results:A total of 57 patients with scalp scar after burn were included in this group, including 31 males and 26 females, aged 13-47 years old. The time from scalp scarring to treatment was 8-41 years. The area of scalp scar was 17-120 cm 2, with an average of 63.3 cm 2. The fat injection volume of 57 patients was 13-75 ml. The hair transplantation was performed 3-8 months after a single fat filling procedure. The total amount of hair transplantation was 510-3 120 FUs. The total score of postoperative scar VSS was 4(3, 4), significantly lower than the preoperative score of 7(6, 7) ( W=6.70, P < 0.001). The color, thickness, blood vessel distribution and softness were significantly reduced compared with those before surgery ( P< 0.01). All patients were followed up for 12-18 months (mean, 14 months) after hair transplantation. The survival rate of hair in hard and thin scar area was 68.2% (22.7 FUs/cm 2/33.3 FUs/cm 2) to 89.7% (26.1 FUs/cm 2/29.1 FUs/cm 2), with an average of 81.3%. In 32 patients, scalp scars were completely covered. The scalp scar of 25 patients was basically covered. Twenty-nine patients were very satisfied with the result of the operation, and 28 patients were satisfied. Conclusion:The high survival rate of hair transplantation can be obtained by injecting fat under the hard and/or thin scalp scars before hair transplantation, which is an effective method to repair scalp scars.

Objective:To investigate the clinical effect of autologous fat transplantation combined with hair transplantation in the treatment of hard and/or thin scalp flat scar after burn.Methods:The clinical data of patients with hard and thin scalp scar after burn admitted to the Department of Plastic Surgery of Peking University Third Hospital from January 2017 to December 2022 were retrospectively analyzed. Fat was extracted from the lower abdomen or outer thigh during the operation, and then injected into the scalp scar after standing for 15 minutes, about 0.8 ml/cm 2 under the hard and/or thin scar area, and 0.2-0.4 ml/cm 2 under the thick and soft scar area. Three months after fat transplantation, hair transplantation was performed in the scar bald area, and the transplant density was 25-35 follicular units (FUs)/cm 2 in the hard and thin scar area, and 30-40 FUs /cm 2 in the thick and soft scar area. The Vancouver scar scale (VSS) was used by two third party plastic surgeons to score the hard and/or thin scar areas of the scalp before and 3 months after scalp fat transplantation. The VSS score was expressed as M ( Q1, Q3), and the preoperative and postoperative data were compared by paired sample Wilcoxon signed rank test. During hair transplantation, the density of implanted hair in the hard and/or thin scar area were recorded. The density of living hair at these sites was measured at the last follow-up, and then the survival rate of hair (living hair density/implant hair density ×100%) was calculated. A third party plastic surgeon evaluated the extent to which scalp scars in the hair transplant area were covered, including completely covered, basically covered, partially covered. Patients’ evaluation with the surgical result was divided into very satisfied, satisfied and dissatisfied. Results:A total of 57 patients with scalp scar after burn were included in this group, including 31 males and 26 females, aged 13-47 years old. The time from scalp scarring to treatment was 8-41 years. The area of scalp scar was 17-120 cm 2, with an average of 63.3 cm 2. The fat injection volume of 57 patients was 13-75 ml. The hair transplantation was performed 3-8 months after a single fat filling procedure. The total amount of hair transplantation was 510-3 120 FUs. The total score of postoperative scar VSS was 4(3, 4), significantly lower than the preoperative score of 7(6, 7) ( W=6.70, P < 0.001). The color, thickness, blood vessel distribution and softness were significantly reduced compared with those before surgery ( P< 0.01). All patients were followed up for 12-18 months (mean, 14 months) after hair transplantation. The survival rate of hair in hard and thin scar area was 68.2% (22.7 FUs/cm 2/33.3 FUs/cm 2) to 89.7% (26.1 FUs/cm 2/29.1 FUs/cm 2), with an average of 81.3%. In 32 patients, scalp scars were completely covered. The scalp scar of 25 patients was basically covered. Twenty-nine patients were very satisfied with the result of the operation, and 28 patients were satisfied. Conclusion:The high survival rate of hair transplantation can be obtained by injecting fat under the hard and/or thin scalp scars before hair transplantation, which is an effective method to repair scalp scars.

Objective:To explore the interleukin-31 protein expression in the hypertrophic scar of incision tissue after surgery and its underlying pathological impact.Methods:From February 2022 to February 2023, three HS patients scar tissue (HS) and their normal skin tissue (Control, NS) were obtained. Two patients were female and one patient was male. The tissues were fixed in 4% formalin and embedded in paraffin. Haematoxylin-eosin (HE) stain and immunohistochemical stain were used to evaluate the epidermal thickness, myofibroblasts of dermis and the expression level of IL-31 between HS and NS.Results:The epidermis thickness was (303.88±46.03) μm in HS group, while (133.02±17.40) μm in NS group ( t=12.60, P<0.001). The expression level of IL-31 protein was measured by IRS score and positive cell density. The IRS score was 9.89±2.03 of the basal layer in HS group and was 4.33±1.66 of the basal layer in NS group. The positive cell density was 786 343.83±159 627.97 of the basal layer in HS group ( P<0.001) and was 555 457.61±128 097.21 of the basal layer in NS group ( P=0.014). In the dermis layer, the IRS score was 7.11±1.05 in HS group and was 4.33±0.71 in NS group, the positive cell density was 156 760.97±26 046.10 in HS group ( P<0.001) and was 49 576.01±52 369.33 in NS group ( P<0.001). In the dermis layer, the count of myofibroblasts was 120.44±15.75 in HS group while was 27.39±14.89 in NS group ( t=23.79, P<0.001). Conclusions:Our study demonstrates that both myofibroblast count and IL-31 protein expression level are notably increased in HS patients. The expression of IL-31 protein is prominent in the cytoplasm of myofibroblasts, basal cells, macrophages and mast cells which could implicate that IL-31 may be a potential therapeutic target to enhance the resolution of HS.

Macrophages are important cell types involved in skin wound healing. In this article, recent advances in macrophage-mediated regulation of skin wound healing and the abnormal polarization of macrophages in diabetic refractory wounds are reviewed. Studies have shown that macrophages in skin wounds can be categorized into two types, M1 and M2. These two types exhibit different functions, including anti-inflammatory effects, angiogenesis promotion, fibroblast promotion and tissue shaping. The dysfunctions of macrophages, cytokine secretion and epigenetic modifications in diabetes mellitus can lead to abnormal polarization of macrophages. Targeting the regulation of macrophage polarization may be an effective approach to addressing skin refractory wounds.

Objective:To investigate the changes of the zygoma, circumzygomatic sutures, and zygomatic arch in children after trans-sutural distraction osteogenesis (TSDO).Methods:A retrospective analysis was performed on skull CT data of cleft lip and palate patients who underwent TSDO to correct midfacial hypoplasia between 2005 and 2019 in Peking University Third Hospital. The Mimics 20.0 software was used for three-dimensional(3D) model reconstruction to observe the morphological changes of the zygoma, circumzygomatic sutures, and zygomatic arch at the end of the traction period after TSDO. Measurements were taken and analyzed for the distances from mp point to 3D reference planes, zygoma height, zygoma width 1, zygoma width 2, zygoma thickness, zygoma volume, zygomaticomaxillary suture width, zygomaticotemporal suture width, zygomaticofrontal suture width, zygomatic arch length, and distances from zygomatic arch landmarks (tp point, zy point, and ju point) to the 3D reference planes. All data were divided into cleft and non-cleft sides. GraphPad Prism 9.4.1 software was used to analyze the changes before and after TSDO. Measurement data of normal distribution was expressed by ± s and the comparison between groups before and after traction was analyzed by paired t-test. Measurement data of non-normal distribution was expressed by M(IQR) and the comparison between groups before and after traction was analyzed by paired Wilcoxon test. If P<0.05, the difference was statistically significant. Results:A total of 27 patients were included in the study, including 23 males and 4 females, with a mean age of (11.19±2.35) years (5-15 years). Of these patients, 10 had bilateral cleft lip and palate, and 17 had unilateral cleft lip and palate (9 on the left side and 8 on the right side). The average traction period was (40.26±11.43) days. The midfacial depression of the patients was corrected after TSDO, and the zygoma grew forward, downward, and horizontally. The circumzygomatic sutures shifted forward. The zygomatic arch showed forward and downward growth. The measurements of zygoma showed that the mp point moved forward by (7.82±3.95) mm on the cleft side and 4.26(5.72) mm on the non-cleft side with statistical differences ( P<0.05). The mp point moved slightly downward, and outward after TSDO compared to before surgery, and these differences were statistically significant ( P<0.05). After TSDO, the zygoma height, width, and volume were all increased compared to preoperative levels, and these differences were statistically significant ( P<0.05). The width of the lower part of the zygomatic bone showed the most significant change, increasing by 4.33(5.17) mm on the cleft side and (3.42±2.67) mm on the non-cleft side and these differences were statistically significant ( P<0.05). There was no statistically significant difference in the thickness of the zygoma after TSDO compared to before surgery ( P>0.05). The widths of circumzygomatic sutures were all increased after TSDO compared to before surgery, and these differences were statistically significant ( P<0.05). The width of zygomaticofrontal suture showed the greatest increase and the width of zygomaticomaxillary suture showed the smallest increase. The length of the zygomatic arch increased after TSDO compared to before surgery, with an increase of (4.78±2.71) mm on the cleft side and (2.03±1.48) mm on the non-cleft side, and these differences were statistically significant ( P<0.05). There was no statistically significant difference in the position of the tp point after TSDO compared to before surgery ( P>0.05), while the position of the zy point and the ju point moved significantly forward and downward, and these differences were statistically significant ( P<0.05). In the horizontal direction, there was no statistically significant difference in the position of the zy point and ju point after TSDO compared to before surgery ( P>0.05). Conclusion:After TSDO, the zygoma shows three-dimensional growth with significant increases in height, width, and volume. The position of zygoma moves forward, downward, and outward. The circumzygomatic sutures widen due to the distraction force, and the zygomatic arch grows forward and downward, with an increase in length.

Macrophages are important cell types involved in skin wound healing. In this article, recent advances in macrophage-mediated regulation of skin wound healing and the abnormal polarization of macrophages in diabetic refractory wounds are reviewed. Studies have shown that macrophages in skin wounds can be categorized into two types, M1 and M2. These two types exhibit different functions, including anti-inflammatory effects, angiogenesis promotion, fibroblast promotion and tissue shaping. The dysfunctions of macrophages, cytokine secretion and epigenetic modifications in diabetes mellitus can lead to abnormal polarization of macrophages. Targeting the regulation of macrophage polarization may be an effective approach to addressing skin refractory wounds.

Objective:To investigate the changes of the zygoma, circumzygomatic sutures, and zygomatic arch in children after trans-sutural distraction osteogenesis (TSDO).Methods:A retrospective analysis was performed on skull CT data of cleft lip and palate patients who underwent TSDO to correct midfacial hypoplasia between 2005 and 2019 in Peking University Third Hospital. The Mimics 20.0 software was used for three-dimensional(3D) model reconstruction to observe the morphological changes of the zygoma, circumzygomatic sutures, and zygomatic arch at the end of the traction period after TSDO. Measurements were taken and analyzed for the distances from mp point to 3D reference planes, zygoma height, zygoma width 1, zygoma width 2, zygoma thickness, zygoma volume, zygomaticomaxillary suture width, zygomaticotemporal suture width, zygomaticofrontal suture width, zygomatic arch length, and distances from zygomatic arch landmarks (tp point, zy point, and ju point) to the 3D reference planes. All data were divided into cleft and non-cleft sides. GraphPad Prism 9.4.1 software was used to analyze the changes before and after TSDO. Measurement data of normal distribution was expressed by ± s and the comparison between groups before and after traction was analyzed by paired t-test. Measurement data of non-normal distribution was expressed by M(IQR) and the comparison between groups before and after traction was analyzed by paired Wilcoxon test. If P<0.05, the difference was statistically significant. Results:A total of 27 patients were included in the study, including 23 males and 4 females, with a mean age of (11.19±2.35) years (5-15 years). Of these patients, 10 had bilateral cleft lip and palate, and 17 had unilateral cleft lip and palate (9 on the left side and 8 on the right side). The average traction period was (40.26±11.43) days. The midfacial depression of the patients was corrected after TSDO, and the zygoma grew forward, downward, and horizontally. The circumzygomatic sutures shifted forward. The zygomatic arch showed forward and downward growth. The measurements of zygoma showed that the mp point moved forward by (7.82±3.95) mm on the cleft side and 4.26(5.72) mm on the non-cleft side with statistical differences ( P<0.05). The mp point moved slightly downward, and outward after TSDO compared to before surgery, and these differences were statistically significant ( P<0.05). After TSDO, the zygoma height, width, and volume were all increased compared to preoperative levels, and these differences were statistically significant ( P<0.05). The width of the lower part of the zygomatic bone showed the most significant change, increasing by 4.33(5.17) mm on the cleft side and (3.42±2.67) mm on the non-cleft side and these differences were statistically significant ( P<0.05). There was no statistically significant difference in the thickness of the zygoma after TSDO compared to before surgery ( P>0.05). The widths of circumzygomatic sutures were all increased after TSDO compared to before surgery, and these differences were statistically significant ( P<0.05). The width of zygomaticofrontal suture showed the greatest increase and the width of zygomaticomaxillary suture showed the smallest increase. The length of the zygomatic arch increased after TSDO compared to before surgery, with an increase of (4.78±2.71) mm on the cleft side and (2.03±1.48) mm on the non-cleft side, and these differences were statistically significant ( P<0.05). There was no statistically significant difference in the position of the tp point after TSDO compared to before surgery ( P>0.05), while the position of the zy point and the ju point moved significantly forward and downward, and these differences were statistically significant ( P<0.05). In the horizontal direction, there was no statistically significant difference in the position of the zy point and ju point after TSDO compared to before surgery ( P>0.05). Conclusion:After TSDO, the zygoma shows three-dimensional growth with significant increases in height, width, and volume. The position of zygoma moves forward, downward, and outward. The circumzygomatic sutures widen due to the distraction force, and the zygomatic arch grows forward and downward, with an increase in length.

BACKGROUND: As a contour-supporting material, the cartilage has a significant application value in plastic surgery.Since the development of hydrogel scaffolds with sufficient biomechanical strength and high biocompatibility, cell-laden hydrogels have been widely studied for application in cartilage bioengineering. This systematic review summarizes the latest research on engineered cartilage constructed using cell-laden hydrogel scaffolds in plastic surgery. METHODS: A systematic review was performed by searching the PubMed and Web of Science databases using selected keywords and Medical Subject Headings search terms. RESULTS: Forty-two studies were identified based on the search criteria. After full-text screening for inclusion and exclusion criteria, 18 studies were included. Data collected from each study included culturing form, seed cell types and sources, concentration of cells and gels, scaffold materials and bio-printing structures, and biomechanical properties of cartilage constructs. These cell-laden hydrogel scaffolds were reported to show some feasibility of cartilage engineering, including better cell proliferation, enhanced deposition of glycosaminoglycans and collagen type II in the extracellular matrix, and better biomechanical properties close to the natural state. CONCLUSION Cell-laden hydrogels have been widely used in cartilage bioengineering research. Through 3-dimensional (3D) printing, the cell-laden hydrogel can form a bionic contour structure. Extracellular matrix expression was observed in vivo and in vitro, and the elastic modulus was reported to be similar to that of natural cartilage. The future direction of cartilage tissue engineering in plastic surgery involves the use of novel hydrogel materials and more advanced 3D printing technology combined with biochemistry and biomechanical stimulation.

Objective:To assess the accuracy and practicability of HaiMed refractory wound artificial intelligence assisted system in wound measurement.Methods:Twenty patients with chronic wounds who were diagnosed and treated from January 2019 to August 2019 in the Plastic Surgery Department of Peking University Third Hospital, including 12 males and 8 females, aged 20-76 years old. The cases included 9 poorly healed wounds, 6 diabetic foot wounds, 4 cases of pressure sores, and 1 case of tumor wounds. The traditional transparent film method and HaiMed system were used to measure the wound area of 20 cases. A paired t-test was performed on the measurement result of the two groups of wound area, and the accuracy and stability of the HaiMed system were statistically analyzed by Spearman simple correlation analysis, Bland-Altman evaluation and coefficient of variation. P<0.05 indicated that the difference was statistically significant. Results:Compared with traditional measurement tools, HaiMed system had no statistically significant difference in wound area measurement ( t=1.997, P=0.060). The Spearman correlation coefficient ( r=0.998) of the two method was consistent. Bland-Altman’s evaluation showed that all scattered points fell within the 95% consistency limit, and the HaiMed system was accurate and reliable. The minimum coefficient of variation of the transparent film hem method group was 0.41%, the maximum was 4.03%, and the average was 1.67%; the coefficient of variation of the HaiMed group was minimum 0.15%, the maximum was 2.31%, and the average was 0.60%. The two had good consistency, and the HaiMed system had higher stability than traditional measurement method. Conclusions:HaiMed system measures the wound area with high accuracy and good stability, especially for superficial wounds. It can be easily and quickly evaluated. HaiMed system is a new and reliable wound measurement tool.

Objective:To assess the accuracy and practicability of HaiMed refractory wound artificial intelligence assisted system in wound measurement.Methods:Twenty patients with chronic wounds who were diagnosed and treated from January 2019 to August 2019 in the Plastic Surgery Department of Peking University Third Hospital, including 12 males and 8 females, aged 20-76 years old. The cases included 9 poorly healed wounds, 6 diabetic foot wounds, 4 cases of pressure sores, and 1 case of tumor wounds. The traditional transparent film method and HaiMed system were used to measure the wound area of 20 cases. A paired t-test was performed on the measurement result of the two groups of wound area, and the accuracy and stability of the HaiMed system were statistically analyzed by Spearman simple correlation analysis, Bland-Altman evaluation and coefficient of variation. P<0.05 indicated that the difference was statistically significant. Results:Compared with traditional measurement tools, HaiMed system had no statistically significant difference in wound area measurement ( t=1.997, P=0.060). The Spearman correlation coefficient ( r=0.998) of the two method was consistent. Bland-Altman’s evaluation showed that all scattered points fell within the 95% consistency limit, and the HaiMed system was accurate and reliable. The minimum coefficient of variation of the transparent film hem method group was 0.41%, the maximum was 4.03%, and the average was 1.67%; the coefficient of variation of the HaiMed group was minimum 0.15%, the maximum was 2.31%, and the average was 0.60%. The two had good consistency, and the HaiMed system had higher stability than traditional measurement method. Conclusions:HaiMed system measures the wound area with high accuracy and good stability, especially for superficial wounds. It can be easily and quickly evaluated. HaiMed system is a new and reliable wound measurement tool.