Objective:To investigate the clinical effect of the modified vertical rectus abdominis myocutaneous flap in repairing the skin and soft tissue defect after abdominoperineal resection for rectal cancer.Methods:This study was a retrospective observational study. From June 2019 to July 2022, five male patients with low rectal cancer who were conformed to the inclusion criteria were admitted to the Department of Basic Surgery of Xiangya Hospital of Central South University, with ages ranging from 65 to 70 years and the sizes of the perianal skin ulcers ranging from 5 cm×4 cm to 11 cm×9 cm, and all of them underwent abdominoperineal resection. The secondary skin and soft tissue defects in the perineum with an area of 8 cm×6 cm-14 cm×12 cm (with the depth of pelvic floor dead space being 10-15 cm) were repaired intraoperatively with transplantation of modified vertical rectus abdominis myocutaneous flaps with the skin area being 9 cm×7 cm-16 cm×12 cm, the volume of the muscle being 18 cm×10 cm×5 cm-20 cm×12 cm×5 cm, and the vessel pedicle being 18-20 cm in length. During the operation, most of the anterior sheath of the rectus abdominis muscle was retained, the flap was transferred to the recipient area through the abdominal cavity, the remaining anterior sheaths of the rectus abdominis muscle on both sides of the donor area were repeatedly folded and sutured, the free edge of the transverse fascia of the abdomen was sutured with the anterior sheath of the rectus abdominis muscle, and the donor area skin was directly sutured. After the operation, the survival of the transplanted myocutaneous flap was observed. The occurrence of complications in the perineal recipient area was recorded within 2 weeks after the operation. The recovery of the perineal recipient area and the abdominal donor area was observed during follow-up, and the occurrence of complications in the donor area of the abdomen as well as the recurrence of tumors and metastasis were recorded.Results:All transplanted myocutaneous flaps in 5 patients survived after surgery. One patient had dehiscence of the incision in the perineal recipient area 2 days after surgery, which healed after 7 d with intermittent dressing changes and routine vacuum sealing drainage treatment. In the other 4 patients, no complications such as incisional rupture, incisional infection, or fat liquefaction occurred in the perineal recipient area within 2 weeks after surgery. Follow-up for 6-12 months after discharge showed that the skin of the perineal recipient area had good color, texture, and elasticity, and was not bloated in appearance; linear scars were left in the perineal recipient area and the abdominal donor area without obvious scar hyperplasia or hyperpigmentation; no complications such as incisional rupture, incisional infection, intestinal adhesion, intestinal obstruction, or weakening of the abdominal wall strength occurred in the abdominal donor area, and the abdominal appearance was good with no localized bulge or formation of abdominal hernia; there was no local recurrence of tumor or metastasis in any patient.Conclusions:The surgical approach of using the modified vertical rectus abdominis myocutaneous flap to repair the skin and soft tissue defects after abdominoperineal resection for rectal cancer is relatively simple in operation, can achieve good postoperative appearances of the donor and recipient areas with few complications, and is worthy of clinical promotion.

Objective:To explore the methods and clinical effects of reconstructing facial and cervical scars with expanded flaps based on the "MLT" principle.Methods:The study was a retrospective observational study. From January 2019 to May 2022, 74 patients with facial and cervical scars after burn or trauma injuries who met the inclusion criteria were admitted to Xiangya Hospital of Central South University, including 38 males and 36 females, aged from 5 to 58 years, including 24 patients with simple facial involvement, 24 patients with simple cervical involvement, and 26 patients with both facial and cervical involvement, with scar area ranging from 12 to 145 cm2. By following the "MLT" principle (color and texture similar to the face; flap area large enough to reconstruct the entire defect; skin tissue thin enough to transmit the expression, so as to facilitate the shape of the face and five features); in the stage Ⅰ surgery, the skin and soft tissue expanders (hereinafter referred to as the expanders) were implanted, and in the stage Ⅱ surgery, the expander removal+scar resection+flap transplantation to repair the secondary wound was performed, and the wound in the donor area of flap was directly sutured. After operation, silicone gel preparation and laser therapy were used to prevent scar hyperplasia. The expansion ratio and time period of expanders, the occurrence of complications of skin and soft tissue expansion surgery, the type of flap used, and the survival of flap after the stage Ⅱ surgery were observed and recorded. The long-term effect of facial and cervical reconstruction and the recovery of donor area and recipient area of flap were evaluated during the postoperative follow-up after surgery.Results:The expansion ratio of 135 expanders ranged from 1.36 to 3.00 times, and the expansion time period ranged from 6 to 14 months. During skin and soft tissue expansion surgery, 8 patients had poor healing of incisions after expander placement, 7 patients had expander rupture, 5 patients had infection in incisions after expander placement, 3 patients had expander exposure, 2 patients had difficult filling the injection pot, and 1 patient had water leakage from the injection pot. Dorsal shoulder expanded flaps with double blood supply of transverse cervical artery and circumflex scapular artery were used in 8 patients, the expanded flaps of anterior transverse carotid artery perforator were used in 11 patients, the expanded flaps of internal thoracic artery perforator were used in 12 patients, tandem expanded flaps of upper chest and neck were used in 16 patients, dorsal thoracic artery perforator expanded flaps were used in 5 patients, and adjacent rotary propulsive expanded flaps were used in 22 patients. After the stage Ⅱ surgery, the flaps of 71 patients were completely survived. One patient had blood circulation disorder in the flap, and the flap survived after hyperbaric oxygen treatment. Necrosis occurred at the end of the flaps in 2 patients, which healed after dressing change. After the surgery, 42 patients were followed up for 3 to 24 months. The color, texture, and thickness of flaps were good and similar to the surrounding normal skin tissue in the recipient area, the appearance and function of the face and neck were significantly improved, and the wound location in the donor and recipient areas of flaps was concealed with slight scar formation.Conclusions:In the reconstruction of facial and neck scars, by following the "MLT" principle, the expanded flap was carefully designed before surgery, the local aesthetic features within the subunit are reconstructed during the stage Ⅱ surgery, and standard anti-scar treatment measures are actively adopted after surgery. After reconstruction, the color, texture, and thickness of flaps were close to the normal skin in face and neck, and the appearance and function of face and neck are significantly improved, with less linear scars left. It is beneficial to improve the therapeutic effect.

Objective:To explore the repair methods of complex facial defect wounds involving paranasal sinuses and their clinical effectiveness.Methods:A retrospective observational study was conducted. From January 2020 to May 2022, 5 patients admitted to the Department of Burns and Plastic Surgery of Xiangya Hospital of Central South University and 4 patients admitted to the Department of Burns and Plastic Surgery of Chenzhou First People's Hospital with complex facial defect wounds involving paranasal sinuses met the inclusion criteria, including 6 males and 3 females, aged 35-69 years, including 4 patients with titanium mesh exposure combined with paranasal sinuses injury and 5 patients with tumor involving paranasal sinuses. After an adequate assessment of the damage by a multiple discipline team, titanium mesh removal, paranasal sinus debridement, and paranasal sinus mucosa removal were performed in patients with exposed titanium mesh, and radical tumor resection was performed in patients with tumors, with postoperative skin and soft tissue defects areas of 5.0 cm×2.5 cm to 18.0 cm×7.0 cm, anterior paranasal sinus wall defects/absence areas of 3 cm×2 cm to 6 cm×4 cm, and sinus cavity depths of 1 to 4 cm. Depending on the perforator course of the descending branch of the lateral circumflex femoral artery, the anterolateral femoral chimeric flap or anterolateral femoral myocutaneous flap (with flap area of 9 cm×4 cm to 19 cm×8 cm, muscle size of 5 cm×3 cm×3 cm to 11 cm×6 cm×3 cm) was transplanted to repair the defect, and the donor site wound was sutured directly. The type of tissue flap transplanted, the blood vessel of the recipient area, and the vascular anastomosis way during the operation, the recovery of the donor and recipient areas and the occurrence of complications after operation were observed. The appearance and blood supply of the recipient area and the recurrence of ulcers and tumors were followed up.Results:The anterolateral femoral myocutaneous flap transplantation was performed in 6 patients, and the anterolateral femoral chimeric flap transplantation was performed in 3 patients. The blood vessels in recipient areas were facial arteries and veins in 3 cases and superficial temporal arteries and veins in 6 cases. The superficial temporal arteries and veins were bridged with blood vessels in tissue flaps by flow-through way in 2 patients, and end-to-end anastomosis of blood vessels in donor and recipient areas was performed in 7 patients. After operation, all the tissue flaps survived, and the facial defect wounds were well repaired without cerebrospinal fluid leakage or paranasal sinus secretion leakage, no intracranial infection occurred, and the wounds in donor areas were healed well. Follow-up of 6-35 months after operation showed that all the patients had good blood supply in the recipient area, and the shape was acceptable; 4 patients with exposed titanium mesh had no recurrence of ulceration, and 5 patients with tumor had no local tumor recurrence or metastasis.Conclusions:Based on an adequate assessment of the extent of paranasal sinuses involved in the facial wound and the nature of the defect, good clinical effects can be achieved by using the anterolateral femoral muscle flap or the anterolateral femoral chimeric flap transplantation to repair complex facial defect wounds with open paranasal sinuses.

Objective:To investigate the effect of activation of microglia in prefrontal cortex on long-term spatial memory in post-stroke depression mice.Methods:Forty-eight male C57BL/6 mice were divided into sham operation group, stroke group, post-stroke depression group and depression group according to the random number table method with 12 in each group, and 36 mice were divided into solvent group, enrofloxacin group and minocycline group according to the random number table method with 12 in each group.Middle cerebral artery occlusion (MCAO) was use to establish the stroke model, and forced swimming was used to establish the depression model.The post-stroke depression model mice were received MCAO first and then received forced swimming on the 4th day after stroke to establish the model.Mice in enrofloxacin group and minocycline group were treated with enrofloxacin and minocycline injection once a clay for 14 days from the 5th day after stroke, respectively.Forced swimming test and sugar water preference test were used to evaluate the depression of mice in each group, Morris water maze test was used to detect the spatial memory function of mice in each group, and Nissl staining and immunofluorescence staining were used to detect the neuronal function and the number and type of microglia activation.The expression of inflammatory cytokines IL-6 and IL-1β were detected by Western blot.GraphPad Prism 8.0.1 statistical software was used for statistical analysis.The single factor variance analysis was used to compare the difference among multiple groups, and pairwise comparison was performed with SNK- q test. Results:(1) There were statistically significant differences in depression, learning and memory, neuron damage, activation of microglia, inflammatory factors and other indicators in sham operation group, stroke group, post-stroke depression group and depression group ( F=43.58-255.70, all P<0.05). Compared with stroke group, post-stroke depression group had longer floating immobility time ((222.70±29.12) s, (79.25±46.78) s, P<0.05), the preference rate of sugar water was significantly lower ( (49.44±6.19) %, (84.49±4.73) %, P<0.05), and the average value of platform approach after correction was higher((125.00±9.95) mm, (96.79±12.57) mm, P<0.05), Nissl bodies expression was lower ((53.50±15.78) cells /mm 2, (85.67±17.52) cells /mm 2, P<0.05), NeuN positive expression rate was lower ((29.78±3.70) %, (45.73±4.51) %, P<0.05), the percent of M1 microglia expression was significantly higher ((75.55±8.84) %, (58.19±5.69) %, P<0.05), the percent of M2 microglia expression was lower ((43.46±5.11)%, (57.14±5.40)%, P<0.05), and the expression levels of IL-6 ((1.14±0.03), (0.94±0.05), P<0.05) and IL-1β((1.17±0.03), (0.56±0.04), P<0.05) were significantly higher.(2) Depression, learning and memory, neuron injury, activation of microglia, inflammatory factors and other indicators of mice in solvent group, enrofloxacin group and minocycline group were significantly different ( F=7.13-94.35, all P<0.05). Compared with enrofloxacin group, mice in minocycline group had shorter floating immobility time ((169.30±13.04) s, (224.30±22.60) s, P<0.05) and higher sugar water preference rate ((62.81±7.75) %, (47.71±8.11) %, P<0.05), the mean value of platform approach estimation after water maze correction was lower ((97.66±14.56) mm, (120.20±12.08) mm, P<0.05), and the expression level of Nissl bodies was higher ((80.17±10.55) cells /mm 2, (52.00±8.94) cells /mm 2, P<0.05), NeuN expression rate was high ((45.04±3.62) %, (28.88±4.50) %, P<0.05), Iba-1 expression was lower ((97.33±10.67) cells/mm 2, (112.50±6.54)cells/mm 2, P<0.05), the percent of M1 microglia expression was lower ((54.43±5.22) %, (73.82±6.88) %, P<0.05), and the percent of M2 microglia expression was significantly higher ((51.86±6.22) %, (36.30±5.72) %, P<0.05). The expression levels of IL-6 ((0.75±0.06), (1.21±0.07), P<0.05) and IL-1β ((0.61±0.06) (1.09±0.09), P<0.05) were lower. Conclusion:The long-term spatial memory impairment of post-stroke depression mice is aggravated, which is related to the neuron damage caused by increased activation of M1 microglia in PFC area.Inhibition of M1 microglia by minocycline can effectively improve the spatial memory ability of mice.

Objective : To explore the role and molecular mechanism of Supervillin in zebrafish embryo development. Methods : Clustal Omega and DNAman software were used to analyze and compare the homology of amino acid sequences of Svil and SVIL in zebrafish and human. The expression pattern of Svila (subtype of Svil protein in zebrafish) during early embryonic development was analyzed by RT⁃PCR and in situ hybridization. Svila expression in zebrafish was inhibited by injecting morphinos ( MO) , and morphological changes of embryos were observed. The expression and nuclear localization of β ⁃catenin protein were detected by Western blot , and the expression of Wnt/β⁃catenin target gene was detected by RT⁃PCR. Results : During the early embryonic development of zebrafish , Svila was maternally expressed and showed an upward trend with the development process. The expression of Svila was reduced by MO , and the development of zebrafish embryos was distorted and the body axis was bent , which might be related to the blocked movement of concentrated extension of embryos. Further studies showed that Svila expression affected β⁃catenin nuclear transport and Wnt/β⁃catenin signaling pathway activation. Conclusion Svila regulates the concentrated extension movement of zebrafish embryos by activating the Wnt/β⁃catenin signaling pathway.

Objective:To investigate the effect of Spautin-1 (an inhibitor of autophagy) on improving anxiety-like behaviors and its mechanism in mice after traumatic brain injury (TBI).Methods:Thirty-six C57BL/6 mice were randomly divided into sham-operated group, TBI group, and TBI+Spautin-1 group ( n=12); TBI models in the latter two groups were established by modified Feeney free fall epidural impingement method. Mice in TBI+Spautin-1 group were administered with Spautin-1 (2 μL, 10 mmol/L) into the lateral ventricle 10 min after modeling, but mice in the other two groups were only injected with same volume of solvent. Neuropathy Symptom Score (NSS) was used to evaluate the functions of motor, sensory and reflexes of mice on 1 st, 7 th and 14 th d of modeling. On 15 th and 16 th d of modeling, open field test and elevated plus maze test were used to evaluate the anxiety-like behaviors in mice. The number of Nissl bodies in the amygdala of mice was calculated by Nissl staining 16 d after modeling. The numbers of neuron specific nucleoprotein (NeuN) positive cells, interleukin (IL)-18 and IL-1β positive astrocytes in the amygdala were detected by immunofluorescent staining. Western blotting was used to detect the autophagy-and pyrotopic-associated protein expressions in the amygdala region of mice. Results:(1) As compared with the sham-operated group, the TBI group and TBI+Spautin-1 group had significantly increased NSS scores on 1 st and 7 th d of modeling ( P<0.05). (2) Open field test showed that as compared with the sham-operated group, the TBI group and TBI+Spautin-1 group had significantly smaller number of crossing grids, significantly decreased percentage of time spending in the central zone ([central area residence time/total time] × 100%), significantly decreased percentage of frequencies entering into opening arm (OE) (OE/[OE+frequencies of entering closing arm]×100%) and opening arm time (OT) percentage (OT/[OT+time of closing arm]×100%); as compared with the TBI group, TBI+Spautin-1 group had significantly larger number of crossing grids, and significantly increased time percentage spending in the central zone, OE percentage, and OT percentage ( P<0.05). (3) As compared with sham-operated group, the TBI group and TBI+Spautin-1 group had significantly smaller numbers of Nissl bodies and NeuN positive cells in the amygdala of mice ( P<0.05); as compared with TBI group, TBI+Spautin-1 group had significantly larger numbers of Nissl bodies and NeuN positive cells in the amygdala of mice ( P<0.05). (4) As compared with the sham-operated group, the TBI group and TBI+Spautin-1 group had significantly increased percentages of IL-1β and IL-18 positive astrocytes in amygdala of mice ( P<0.05); as compared with the TBI group, the TBI+Spautin-1 group had significantly decreased percentages of IL-1β and IL-18 positive astrocytes in amygdala of mice ( P<0.05). (5) As compared with sham-operated group, the TBI group and TBI+Spautin-1 group had significantly higher protein expressions of NOD-like receptor family protein 3 (NLRP3), activated cysteine aspartate protease-1 (Caspase-1), pore-forming protein D-N terminal fragment (GSDMD-N), ubiquitin specific peptidase (USP) 13 and B-lymphocytoma-2 interacting protein (Beclin1), and statistically higher ratio of microtubule-associated protein 1 light chain (LC)3 II/LC3 I ( P<0.05); as compared with TBI group, the TBI+Spautin-1 group had significantly decreased protein expressions of NLRP3, activated Caspase-1, GSDMD-N, USP13 and Beclin1 in the amygdala, and statistically lower ratio of LC3 II/LC3 I ( P<0.05). Conclusion:Spautin-1 improves the anxiety-like behaviors in mice after TBI, whose mechanism may be associated with the inhibition of astrocytic pyroptosis in the amygdala.

Objective:To evaluate the efficacy and safety of the micro-crosslinked hyaluronic acid injected by Shuiguang Needle Injection in facial rejuvenation.Methods:Thirty-two patients were enrolled. In this split face study, micro-crosslinked hyaluronic acid and non-crosslinked hyaluronic acid were randomly applied in the treated side of the face. Procedure efficacy (judged by VISIA), complication and subjects＇ satisfaction were assessed before treatment, one month, two months and three months after treatment.Results:According to the VISIA, 32 cases were effective one month after treatment on the treatment side, accounting for 100%; 28 cases were effective three months after the end of treatment, accounting for 87.51%. On the control side, 28 cases were effective one month after treatment, accounting for 87.50%, and 7 cases were effective after three months, accounting for 21.88%. There was no statistically significant difference in complications between the left and right sides; 31 patients were satisfied on the treatment side, accounting for 96.88%, and 28 patients on the control side were satisfied, accounting for 87.50%.Conclusions:The micro-crosslinked hyaluronic acid injected by Shuiguang Needle Injection appears to be effective and durable for facial rejuvenation. And it has a low complication rate and high subject satisfaction.

Objective:To explore the repair methods and clinical effects of full-thickness burn wounds deep to tendon or even bone in fingers.Methods:A retrospective non-randomized controlled trial was conducted on the 98 patients with full-thickness finger burns deep to tendon or even bone who met the inclusion criteria and were hospitalized in Xiangya Hospital of Central South University from January 2010 to December 2019. Among the 98 patients, there were 81 males and 17 females, aged from 1 to 72 years, with 160 fingers involved. The wound area of each of affected fingers ranged from 2.0 cm×1.5 cm to 12.0 cm×3.5 cm, and the maximum wound area after merging the affected fingers was 12.0 cm×10.0 cm. For adult hands with multiple full-thickness burn wounds deep to tendon or even bone in multiple fingers or children with full-thickness finger burns deep to tendon or even bone, pedicled abdominal flaps were selected. For adults with single or two fingers with full-thickness burns deep to tendon or even bone, the pedicled internal hand flaps and free tissue flaps were selected. The free tissue flap repair requires good vascular conditions in the recipient area with arteries and veins available for anastomosis. For thumb nail burns deep to tendon or even bone or partial absence of the thumb after burns, the thumbs were reconstructed with the first toenail flap or dorsal foot flap with the second toe. In this study, 45 pedicled abdominal flaps were used to repair the wounds in 91 fingers, 37 pedicled internal hand flaps were used to repair the wounds in 37 fingers, 26 free tissue flaps were used to repair the wounds in 28 fingers, 3 first toenail flaps were used to reconstruct 3 patients' thumb nails and to repair hand wounds, and 1 dorsal foot flap with the second toe was used to reconstruct 1 patient's thumb and to repair hand and wrist wounds. The tissue flap area was from 2.0 cm×1.5 cm to 20.0 cm×10.0 cm. The wound in the donor site was repaired by direct suture or full-thickness skin grafting from the medial upper arm of the affected limb or split-thickness skin grafting from the outer thigh. The postoperative survival of the tissue flap, postoperative complications, and appearance and function of the flap donor site were observed. For the patients who were followed up, their finger functions were evaluated at the last follow-up using the trial criteria for replantation function evaluation of the amputated finger issued by the Hand Surgery Society of the Chinese Medical Association, and the satisfaction of the patients was investigated using the Efficacy Satisfaction Scale. Data were statistically analyzed with Kruskal-Wallis H test and Nemenyi test. Results:Of the 112 tissue flaps, 104 tissue flaps survived completely and had good blood circulation; 1 pedicled thumb dorsal ulnar reverse island flap, 1 pedicled finger artery cutaneous branch reverse island flap, and 1 free grafted anterolateral thigh perforator flap were slightly necrotic at the end, which were repaired with outer thigh split-thickness skin graft after dressing change and granulation tissue growth; 2 free grafted tarsal external artery flaps and 1 pedicled thumb dorsal ulnar reverse island flap suffered from postoperative venous return obstruction, which survived after partial suture removal and heparin saline cleansing of the wound; 1 pedicled modified dorsal metacarpal artery retrograde island flap and 1 free grafted peroneal artery perforator flap were necrotic, which were repaired by a pedicled abdominal flap and a lateral upper arm flap free transplantation respectively in stage Ⅱ. After transplantation, the tissue flaps had good shape, soft texture, and good elasticity, without bloating. There was no functional disorder in the flap donor site, and only slight scar remained. A total of 117 fingers of the 72 patients received 3-24 months of outpatient or telephone follow-up. At the last follow-up, the excellent and good rates of function evaluation of fingers repaired with pedicled abdominal flap, pedicled internal hand flap, and free tissue flap were respectively 77.3% (51/66), 96.3% (26/27), and 95.8% (23/24). The function of fingers repaired with free tissue flap and pedicled internal hand flap was significantly better than that with pedicled abdominal flap ( P<0.01). The satisfaction of patients with fingers repaired by free tissue flaps was significantly higher than that by pedicled abdominal flap ( P<0.05). Conclusions:According to the specific situation of full-thickness burn wounds deep to tendon or even bone in fingers, the pedicled abdominal flap is used to repair the multiple full-thickness burn wounds deep to tendon or even bone in multiple fingers of adult or the full-thickness burn wounds deep to tendon or even bone in fingers of children, the pedicled internal hand flap or free tissue flap is used to repair the full-thickness burn wounds deep to tendon or even bone in single or two fingers of adult patients, and the first toenail flap or the dorsal foot flap with the second toe is used to reconstruct the thumbs with full-thickness burn deep to tendon or even bone, with high postoperative tissue flap survival rate and few complications. The functional recovery of the affected finger is better after repair with free tissue flap and pedicled internal hand flap, and the patients' satisfaction is the highest after free tissue flap repair.

Objective:To explore the clinical effects of simultaneous reconstruction of multiple joint scar contracture deformity of limb.Methods:From January 2010 to June 2018, 24 patients with multiple joint scar contracture deformity of the same limb were reconstructed in simultaneous operations in Xiangya Hospital of Central South University, including 16 males and 8 females, aged 3-42 years, with 15 patients having deformities in the upper limbs and 9 patients having deformities in the lower limbs. One operation was performed to repair contracture deformity of axillary fossa and elbow in 3 patients, cubital fossa and palmar of wrist in 4 patients, cubital fossa and hand in 5 patients, palmar of wrist, palm, and palmar of finger in 3 patients, groin and medial knee in 2 patients, popliteal fossa and posterior ankle in 1 patient, and anterior ankle and dorsum of foot in 6 patients. After the release of various joint scar contractures, the area of skin defect was 140 to 580 cm 2. Autologous full-thickness skin grafts were used in 7 patients, autologous medium-thickness skin grafts were used in 4 patients, autologous full-thickness skin grafts combined with local skin flaps were used in 9 patients, and allogeneic acellular dermal matrix and autologous thin skin grafts were used in 4 patients. Comprehensive measures for rehabilitation were taken and the survival of the skin graft was observed after operation. Six months to eight years after the operation, all the patients were followed up for the functions of the affected limbs, among which the functions of the upper limbs were evaluated according to the trial standard for the evaluation of the functions of the upper limbs of the Hand Surgery Society of the Chinese Medical Association. The joint mobility, walking, and squatting function of lower extremity were examined after operation. Recurrence of contractures in all the affected limbs and reoperation were recorded. Results:The grafts survived after operation in 22 patients. Two patients had necrosis in small full-thickness skin area, of which one was healed by skin grafting after debridement, and the other one was healed after dressing changes. The deformity of scar contracture at each repaired joint was completely or partially corrected. During a follow-up for 6 to 96 months, the upper limb functions of 15 patients were rated excellent in 12 patients and good in 3 patients. Among the 9 patients of lower limb scar contractures, except for one 3-year-old child who experienced recurrence of medial knee scar contracture and underwent surgical release and skin grafting 5 years later, the remaining 8 patients basically recovered normal joint functions with pretty good outcomes.Conclusions:For continuous scar contracture deformity of multiple joints of the same limb, simultaneous surgical release and skin grafting can reduce operation frequency and obtain better outcomes of surgical operation.

Objective:To establish an artificial intelligence burn depth recognition model based on convolutional neural network, and to test its effectiveness.Methods:In this evaluation study on diagnostic test, 484 wound photos of 221 burn patients in Xiangya Hospital of Central South University (hereinafter referred to as the author′s unit) from January 2010 to December 2019 taken within 48 hours after injury which met the inclusion criteria were collected and numbered randomly. The target wounds were delineated by image viewing software, and the burn depth was judged by 3 attending doctors with more than 5-year professional experience in Department of Burns and Plastic Surgery of the author′s unit. After marking the superficial partial-thickness burn, deep partial-thickness burn, or full-thickness burn in different colors, the burn wounds were cut according to 224×224 pixels to obtain 5 637 complete wound images. The image data generator was used to expand images of each burn depth to 10 000 images, after which, images of each burn depth were divided into training set, verification set, and test set according to the ratio of 7.0∶1.5∶1.5. Under Keras 2.2.4 Python 2.8.0 version, the residual network ResNet-50 of convolutional neural network was used to establish the artificial intelligence burn depth recognition model. The training set was input for training, and the verification set was used to adjust and optimize the model. The judging accuracy rate of various burn depths by the established model was tested by the test set, and precision, recall, and F1_score were calculated. The test results were visualized to generate two-dimensional tSNE cloud chart through the dimensionality reduction tool tSNE, and the distribution of various burn depths was observed. According to the sensitivity and specificity of the model for the recognition of 3 kinds of burn depths, the corresponding receiver operator characteristics (ROC) curve was drawn, and the area under the ROC curve was calculated.Results:(1) After the testing of the test set, the precisions of the artificial intelligence burn depth recognition model for the recognition of superficial partial-thickness burn, deep partial-thickness burn, or full-thickness burn were 84% (1 095/1 301), 81% (1 215/1 499) and 82% (1 395/1 700) respectively, the recall were 73% (1 095/1 500), 81% (1 215/1 500) and 93% (1 395/1 500) respectively, and the F1_scores were 0.78, 0.81, and 0.87 respectively. (2) tSNE cloud chart showed that there was small overlapping among different burn depths in the test results for the test set of artificial intelligence burn depth recognition model, among which the overlapping between superficial partial-thickness burn and deep partial-thickness burn and that between deep partial-thickness burn and full-thickness burn were relatively more, while the overlapping between superficial partial-thickness burn and full-thickness burn was relatively less. (3) The area under the ROC curve for 3 kinds of burn depths recognized by the artificial intelligence burn depth recognition model was ≥0.94.Conclusions:The artificial intelligence burn depth recognition model established by ResNet-50 network can rather accurately identify the burn depth in the early wound photos of burn patients, especially superficial partial-thickness burn and full-thickness burn. It is expected to be used clinically to assist the diagnosis of burn depth and improve the diagnostic accuracy.