Objective:To explore the clinical effects of early rehabilitation treatment after repair surgery of skin and soft tissue defects accompanied by extensor tendon injury on the back of hand.Methods:This study was a retrospective non-randomized controlled study. From February 2015 to February 2023, 24 patients (15 males and 9 females, aged 12-55 years) with skin and soft tissue defects accompanied by extensor tendon injury on the back of hand, who met the inclusion criteria and were repaired with flap transplantation and tendon grafting or tendon anastomosis, were admitted to the First Affiliated Hospital of Air Force Medical University. According to different intervention time for postoperative rehabilitation treatment of patients, the patients were divided into conventional rehabilitation group and early rehabilitation group, with 12 cases in each group. Patients in early rehabilitation group received rehabilitation treatment immediately after surgery under the rehabilitation guidance of specialized rehabilitation physicians based on the characteristics of different postoperative periods. Patients in conventional rehabilitation group began rehabilitation treatment from the third week after surgery, and their rehabilitation treatment was the same as that of patients in early rehabilitation group from the second week after surgery. The patients in 2 groups were treated in the hospital until the sixth week after surgery. The occurrence of flap vascular crisis and tendon rupture were observed within 6 weeks after surgery. After 6 weeks of surgery, the manual muscle test was used to measure the pinching force between the index finger and thumb, lateral pinching force, three-point pinching force, and grip force of the affected hand; the total action motion method was used to evaluate the finger joint range of motion of the affected hand, and the excellent and good ratio was calculated; the Carroll upper extremity function test was used to score and rate the function of the affected hand.Results:Within 6 weeks after surgery, only 1 patient in conventional rehabilitation group suffered from venous crisis, and the flap survived after the second surgical exploration and anastomosis of blood vessels; there was no occurrence of tendon rupture in patients of 2 groups. After 6 weeks of surgery, there were no statistically significant differences in pinching force between the index finger and thumb, lateral pinching force, three-point pinching force, or grip force of the affected hand between the two groups of patients ( P>0.05); the excellent and good ratio of the finger joint range of motion of the affected hand of patients in early rehabilitation group was 11/12, which was higher than 7/12 in conventional rehabilitation group, but there was no statistically significant difference ( P>0.05); the affected hand function score of patients in early rehabilitation group was 90±6, which was significantly higher than 83±8 in conventional rehabilitation group ( t=2.41, P<0.05); the function rating of the affected hand of patients in early rehabilitation group was obviously better than that in conventional rehabilitation group ( Z=2.04, P<0.05). Conclusions:Early rehabilitation treatment for patients with skin and soft tissue defects accompanied by extensor tendon injury on the back of hand after repair surgery can improve hand function, but it would not increase surgery related complications, which is worthy of clinical promotion and application.

Bedridden patients mostly use the back cushion object,raise the bedside position,and other methods to obtain the semi-decumbent position.However,the existing methods have shortcomings such as insufficient execution,wrong angle estimation,weak consciousness,forgetting,decreased comfort,easy to cause pressure sore and aspiration pneumonia.To solve the shortcomings of the existing eating position placement method,the department of geriatric medicine team of Tongxiang City Hospital of Traditional Chinese Medicine designed a bed-rest pillow for bed patients to eat or other requirements of semi-lying position,and obtained the National Utility Model Patent of China(patent number:ZL 202122859891.4).This device places the pillow on a flat bed,with the back of the pillow next to the head of the bed for support and to prevent sliding.The patient was placed in a retainer slot,head in the first retainer slot,shoulder and back in the second retainer slot,waist and abdomen in the third retainer slot,and hands on the armrests on both sides of the pillow.The use of pillows for bedridden patients is simple and easy to learn,convenient,economical and practical,time-saving and labor-saving,and convenient supervision and inspection,which can reduce complications such as aspiration and pressure ulcers,thereby reducing the economic burden of the patient,improving the quality of life,and improving the satisfaction of patients and their families,and is worthy of clinical promotion and use.

Objective:To investigate the role of 20 MHz high-frequency ultrasound in evaluating scar thickness and morphology.Methods:The clinical data of patients with the initial stage of scar formation after burn trauma (<1 month), hypertrophic scar (1-6 months) and atrophic scar (>6 months) treated by the Department of Burn and Cutaneous Surgery, the First Affiliated Hospital of Air Force Medical University from April 2019 to December 2020, were retrospectively analyzed. All patients were evaluated by 20 MHz high-frequency ultrasound, histopathology and Vancouver scar scale (VSS). Three measurement points were randomly selected at the scar during ultrasonic examination, and the average value was recorded as the ultrasonic thickness measurement value. The scar tissue samples were collected from the site of ultrasonic examination, and HE staining and Masson staining were performed. At the same time, scar thickness was evaluated by two physicians using VSS. The difference of scar thickness assessment result among the 3 method in patients at the initial stage of scar formation, hypertrophic scar and atrophic scar was compared. Meanwhile, the relationship between the characteristics of 20 MHz high-frequency ultrasound and histopathology was compared. The measurement data of normal distribution were expressed as Mean±SD. One-way ANOVA was used for comparison among three groups, and SNK- q test was used for pairwise comparison between groups. Counting data were analyzed by Chi-square test. Results:A total of 224 patients were included, including 91 males and 133 females, aged from 1 to 34 years, with an average age of 25.7 years. There were 79 patients at the initial stage of scar formation, 102 at the hypertrophic stage, and 43 at the atrophic stage. (1) In the initial stage of scar formation, the thickness measured by 20 MHz ultrasound was about (2.01±0.68) mm, the thickness evaluated by VSS was (1.72±0.49) mm, and the thickness measured by pathological section was (2.11±0.45) mm. In the hyperplastic scar stage, the thickness measured by 20 MHz ultrasound was (4.11±0.73) mm, the thickness evaluated by VSS was (3.02±0.47) mm, and the thickness measured by pathological section was (4.27±0.44) mm. In the atrophic scar stage, the thickness measured by 20 MHz ultrasound was (1.74±0.64) mm, the thickness measured by VSS was (1.77±0.61) mm, and the thickness measured by pathological section was (1.71±0.67) mm. For scars in the above three periods, there was no statistical significance between scar thickness measured by 20 MHz high-frequency ultrasound and that measured by pathological sections(all P<0.05). In the initial stage of scar formation and hypertrophic stage, the thickness evaluated by VSS was significantly different from that measured by 20 MHz high-frequency ultrasound and pathology (all P<0.05), respectively. (2) Echo intensity was evaluated by ultrasound. In the initial stage of scar formation, the thickness of the epidermis shown by high-frequency ultrasound was close to that of the normal epidermis and presented a high-intensity echo, but there was a strip of echoless or no echo zone of <1 mm between the high-intensity echo epidermis and dermis, which looked like dermal edema. Pathology showed that there were acanthoid changes in the epidermis of the scar at this stage, rich capillaries and a small amount of collagen fibrous tissue in the dermis. In the hyperplastic scar stage, the scar epidermis still showed strong echo, while the dermis showed uneven echo, the superficial dermis showed obvious isoecho, and the deep dermis showed no echo or hypoecho. Pathology showed that the epidermis was thin and smooth, and keratosis was obvious. Collagen fibers parallel to the epidermis could be seen in the superficial layer of the dermis, with regular arrangement. Collagen fibers were increased and thickened in the deep layer of the dermis, in the shape of nodules and swirls. In the atrophic scar stage, the scar epidermis presented a strong echo, and there was no obvious demarcation between the dermis and subcutaneous tissue, presenting a uniform echo. Pathological findings showed that the epidermis became thinner with a "skin nails" -like structure, the junction between the superficial and deep dermis was not obvious, and the collagen fibers were arranged in parallel or oblique direction, and the surface boundary was unclear. Conclusion:20 MHz high-frequency ultrasound is more accurate than VSS in the assessment of thickness of hypertrophic scar, and can reflect the collagen content and moisture ratio in scar. Compared with pathological examination, it has the advantages of non-invasive and fast, and is an effective means to evaluate scar thickness and morphology.

Objective:To investigate the role of 20 MHz high-frequency ultrasound in evaluating scar thickness and morphology.Methods:The clinical data of patients with the initial stage of scar formation after burn trauma (<1 month), hypertrophic scar (1-6 months) and atrophic scar (>6 months) treated by the Department of Burn and Cutaneous Surgery, the First Affiliated Hospital of Air Force Medical University from April 2019 to December 2020, were retrospectively analyzed. All patients were evaluated by 20 MHz high-frequency ultrasound, histopathology and Vancouver scar scale (VSS). Three measurement points were randomly selected at the scar during ultrasonic examination, and the average value was recorded as the ultrasonic thickness measurement value. The scar tissue samples were collected from the site of ultrasonic examination, and HE staining and Masson staining were performed. At the same time, scar thickness was evaluated by two physicians using VSS. The difference of scar thickness assessment result among the 3 method in patients at the initial stage of scar formation, hypertrophic scar and atrophic scar was compared. Meanwhile, the relationship between the characteristics of 20 MHz high-frequency ultrasound and histopathology was compared. The measurement data of normal distribution were expressed as Mean±SD. One-way ANOVA was used for comparison among three groups, and SNK- q test was used for pairwise comparison between groups. Counting data were analyzed by Chi-square test. Results:A total of 224 patients were included, including 91 males and 133 females, aged from 1 to 34 years, with an average age of 25.7 years. There were 79 patients at the initial stage of scar formation, 102 at the hypertrophic stage, and 43 at the atrophic stage. (1) In the initial stage of scar formation, the thickness measured by 20 MHz ultrasound was about (2.01±0.68) mm, the thickness evaluated by VSS was (1.72±0.49) mm, and the thickness measured by pathological section was (2.11±0.45) mm. In the hyperplastic scar stage, the thickness measured by 20 MHz ultrasound was (4.11±0.73) mm, the thickness evaluated by VSS was (3.02±0.47) mm, and the thickness measured by pathological section was (4.27±0.44) mm. In the atrophic scar stage, the thickness measured by 20 MHz ultrasound was (1.74±0.64) mm, the thickness measured by VSS was (1.77±0.61) mm, and the thickness measured by pathological section was (1.71±0.67) mm. For scars in the above three periods, there was no statistical significance between scar thickness measured by 20 MHz high-frequency ultrasound and that measured by pathological sections(all P<0.05). In the initial stage of scar formation and hypertrophic stage, the thickness evaluated by VSS was significantly different from that measured by 20 MHz high-frequency ultrasound and pathology (all P<0.05), respectively. (2) Echo intensity was evaluated by ultrasound. In the initial stage of scar formation, the thickness of the epidermis shown by high-frequency ultrasound was close to that of the normal epidermis and presented a high-intensity echo, but there was a strip of echoless or no echo zone of <1 mm between the high-intensity echo epidermis and dermis, which looked like dermal edema. Pathology showed that there were acanthoid changes in the epidermis of the scar at this stage, rich capillaries and a small amount of collagen fibrous tissue in the dermis. In the hyperplastic scar stage, the scar epidermis still showed strong echo, while the dermis showed uneven echo, the superficial dermis showed obvious isoecho, and the deep dermis showed no echo or hypoecho. Pathology showed that the epidermis was thin and smooth, and keratosis was obvious. Collagen fibers parallel to the epidermis could be seen in the superficial layer of the dermis, with regular arrangement. Collagen fibers were increased and thickened in the deep layer of the dermis, in the shape of nodules and swirls. In the atrophic scar stage, the scar epidermis presented a strong echo, and there was no obvious demarcation between the dermis and subcutaneous tissue, presenting a uniform echo. Pathological findings showed that the epidermis became thinner with a "skin nails" -like structure, the junction between the superficial and deep dermis was not obvious, and the collagen fibers were arranged in parallel or oblique direction, and the surface boundary was unclear. Conclusion:20 MHz high-frequency ultrasound is more accurate than VSS in the assessment of thickness of hypertrophic scar, and can reflect the collagen content and moisture ratio in scar. Compared with pathological examination, it has the advantages of non-invasive and fast, and is an effective means to evaluate scar thickness and morphology.

Reports a case admitted in the Ward I of Department of Surgery of Zhengzhou Renji Hospital in June 2017. A young child who suffered destructive injury of left forearm, wrist and palm with severed 3rd-5th fingers. Tendon and neurovascular repairs of forearm, wrist and palm were performed with pedicled abdomina flap and the 3rd-5th fingers ectopic replantation in Phase I surgery. In the Phase II surgery, the abdomina flap division was carried out. The replantation of severed fingers after ectopic replantation and the reconstruction of foot defect with free anterolateral thigh flap(ALTF) were carried out in Phase III surgery. In Phase IV surgery, fingers functional reconstruction and foot flap thinning were performed. Four years after surgery, the thumb oppositions to middle, ring and little fingers could be completed, with slightly limitations. The appearance and texture of transferred foot flap were good, and the child could walk and run almost normally.

Objective:To investigate the morphological characteristics of coracoid process in different stages of temporomandibular joint osteoarthrosis (TMJOA), and to provide theoretical data for clinical and anatomic study.Methods:A total of 290 patients who were diagnosed with TMJOA in the Department of Temporomandibular Joint, Kunming Medical University School and Hospital of Stomatology from January 2015 to February 2021 were collected, including 69 males and 221 females, with age of (35.1±13.7) years (16-69 years old), 64 cases of unilateral lesions (64 sides), and 226 cases of bilateral lesions (452 sides). According to the TMJOA X-ray staging standard put forward by Ma Xuchen in 2005, the affected joints were divided into stage Ⅰ (227 sides), stage Ⅱ (38 sides), stage Ⅲ (164 sides) and stage Ⅳ (87 sides). Twenty-six patients without clinical and imaging manifestations of temporomandibular disorders in the Department of Radiology, Kunming Medical University School and Hospital of Stomatology from October 2020 to June 2021 were selected as the control group, including 8 males and 18 females. The age was (34.3±13.9) years (17-60 years). The dicom data of each group were imported into Simplant Pro 11.04 software to measure the height of coracoid process, anteversion angle and the ratio of coracoid vertex to mandibular corner to condylar vertex to mandibular angle. R 3.6.1 was used to analyze the difference of the morphological characteristics of coracoid process between in the affected side of TMJOA and in the both sides of the control group, in the healthy side and the affected side of unilateral patients and in different stages of TMJOA.Results:The height of the coracoid process [(16.26±2.81) mm], the ratio of the coracoid process vertex-mandibular angle point and the condyle vertex-mandibular angle point distance [0.96(0.92,1.01)] on the affected side of TMJOA were significantly higher than those in the control group [(15.31±3.03) mm; 0.95(0.89, 0.99)] ( t=2.18, P=0.033; Z=2.87, P=0.004). There was no significant difference between the ante-version angle and the control group ( t=-1.37, P=0.176). The ratio of the distance between the apex of the coracoid process and the apex of the mandibular angle to the apex of the condyle and the angle of the mandible in the affected side of unilateral patients was significantly greater than that in the healthy side ( t=-3.46, P=0.001). There was no significant difference in coracoid height, coracoid anteversion angle and the healthy side ( t=-1.85, P=0.069; t=-0.06, P=0.955) in different periods. The intra-group analysis showed that there was no significant difference in the height of the coracoid process in different stages ( F=0.37, P=0.774). There was no significant difference in the ante-version angle of the coracoid process: stage Ⅰ, stage Ⅱ, and stage Ⅲ ( P>0.008), but all were significantly smaller than stage Ⅳ ( PⅠ-Ⅳ<0.001, PⅡ-Ⅳ=0.009, PⅢ-Ⅳ<0.001). The ratio of the distance between coracoid apex-mandibular angle and condyle apex-mandibular angle: there was no significant difference in stage Ⅰ, stage Ⅱ, and stage Ⅲ ( P>0.008), and stage Ⅰ and stage Ⅲ were significantly smaller than stage Ⅳ ( P<0.001). Conclusions:The coracoid height and the ratio of the coracoid apex-mandibular angle to the condyle apex-mandibular angle distance on the TMJOA side were significantly greater than those without temporomandibular joint disorders. The bone deposition was mainly concentrated in the upper and posterior part of the condyle. TMJOA had a certain correlation with the height of the coracoid process.

Objective:To study the clinical value of left ventricle Tei index in evaluating hemodynamics after interventional therapy of patent ductus arteriosus (PDA).Methods:From May 2017 to May 2019, 50 children with PDA who underwent interventional therapy (PDA group) and 27 healthy children (healthy control group) in Anhui Provincial Children’s Hospital were selected. The left ventricle Tei index, plasma brain natriuretic peptides (BNP), left ventricular end-diastolic dimension (LVDD), left ventricular ejection fraction (LVEF) were compared between 2 groups.Results:The left ventricle Tei index was not correlated with heart rate and age in 2 groups ( P>0.05). The left ventricle Tei index before operation in PDA group was significantly lower than that in healthy control group: 0.20(0.16, 0.25) vs. 0.27(0.20, 0.30), and there was statistical difference ( P<0.05). In PDA group, the left ventricle Tei index immediately, 3 d, 1 month and 3 months after operation was significantly higher than before operation: 0.38(0.29, 0.47), 0.32(0.26, 0.40), 0.30(0.27, 0.35) and 0.32(0.26, 0.37) vs. 0.20(0.16, 0.25), and there was statistical difference ( P<0.05); the plasma BNP immediately after operation was significantly lower than before operation: 288 (126, 433) ng/L vs. 582 (303, 1 675) ng/L, and there was statistical difference ( P<0.05); the LVDD 3 months after operation was significantly lower than before operation: (3.03 ± 0.54) cm vs. (3.38 ± 0.51) cm, and there was statistical difference ( P<0.05); the LVEF immediately after operation was significantly lower than before operation: (54.24 ± 6.09)% vs. (59.45 ± 5.93)%, the LVEF 1 and 3 months after operation was significantly higher than that immediately after operation: (63.18 ± 4.71)% and (65.46 ± 4.78)% vs. (54.24 ± 6.09)%, and there were statistical differences ( P<0.05). The left ventricle Tei index before operation was negatively correlated with inner diameter of PDA and plasma BNP ( r = -0.362 and -0.388, P = 0.013 and 0.009), and there was no correlation between LVDD and LVEF ( r = -0.192 and -0.283, P = 0.229 and 0.053); the differences of Tei index before operation and immediately after operation (ΔTei) was positively correlated with inner diameter of PDA ( r = 0.325, P = 0.030), and there was no correlation with BNP, LVDD and LVEF ( r = 0.234, 0.283 and -0.039, P = 0.126, 0.076 and 0.798). Conclusions:The left ventricle Tei index can quickly and accurately assess the change of hemodynamics after interventional therapy of PDA.

Objective:To observe the influence of different treatment intervals of pulsed dye laser (PDL) in treating hypertrophic scar after burn, and to explore the optimal treatment interval.Methods:From May 2018 to March 2019, 20 burn patients who met the inclusion criteria and were admitted to the First Affiliated Hospital of Air Force Medical University were included in this prospective randomized controlled study. Patients were divided into 1 week group (4 patients, 2 males and 2 females, aged 27 (4, 67) years, 19 scars), 2 weeks group (5 patients, 2 males and 3 females, aged 9 (3, 55) years, 15 scars), 3 weeks group (5 patients, 4 males and 1 female, aged 26 (19, 45) years, 15 scars), and 4 weeks group (6 patients, 4 males and 2 females, aged 31 (14, 48) years, 13 scars), according to the random number table, and treated with PDL with the treatment intervals of 1 week, 2 weeks, 3 weeks, and 4 weeks, respectively, with total treatment cycle of 3 months. Before the first treatment and three months after the first treatment, the Vancouver Scar Scale (VSS) was conducted and the decreased value of VSS score was calculated; the laser Doppler blood flow meter was used to measure scar blood perfusion and the proportion of change in blood perfusion volume was calculated. Data were statistically analyzed with Kruskal-Wallis test, Wilcoxon rank sum test, Wilcoxon symbolic rank sum test, Bonferroni correction, and Fisher′s exact probability test.Results:The VSS scores of patients in 1 week group, 2 weeks group, 3 weeks group, and 4 weeks group in three months after the first treatment were significantly lower than those before the first treatment ( Z=-3.74, -3.47, -2.69, -3.25, P<0.01). There were no statistically significant differences in the decreased values of VSS scores in three months after the first treatment among the patients in 4 groups ( H=2.35, P>0.05). Three months after the first treatment, the blood perfusion volumes of patients in 2 weeks group and 3 weeks group were significantly lower than those before the first treatment ( Z=-2.95, -2.50, P<0.05 or P<0.01). The proportions of changes in blood perfusion volume of patients in 1 week group, 2 weeks group, 3 weeks group, and 4 weeks group were respectively -0.02 (-1.05, 0.69), -0.29 (-0.75, 0.18), -0.11 (-0.55, 0.23), 0.05 (-0.61, 0.75). There were statistically significant differences among the 4 groups ( H=9.39, P<0.05). The proportions of changes in blood perfusion volume of patients in 2 weeks group was statistically higher than that of 1 week group ( Z=2.76, P<0.01). Conclusions:PDL treatment can reduce the VSS score and blood perfusion volume of scar. One treatment every two weeks or three weeks improve the scar blood perfusion volume more significantly, and can be recommended as the appropriate treatment interval of PDL for hypertrophic scar after burn.

Objective:To explore the clinical effects of expanded flap made by skin and soft tissue expander (hereinafter referred to as expander) in repairing the wounds with exposed titanium mesh after cranioplasty with titanium mesh.Methods:A retrospective observational study was conducted. From April 2015 to October 2019, 13 patients with wounds with exposed titanium mesh after cranioplasty with titanium mesh were admitted to the First Affiliated Hospital of Air Force Medical University, including 10 males and 3 females, aged 18 to 70 years. Exposure of titanium mesh occurred 3 months to 4 years after cranioplasty with titanium mesh. The wound area of exposed titanium mesh ranged from 1.5 cm×0.6 cm to 6.3 cm×6.0 cm. In the first stage, one or two square expanders with rated capacity of 50-200 mL were placed under the normal scalp 1 cm away from the edge of the wound surface of exposed titanium mesh. The water injection time was 2 to 3 months with the total water injection volume being 1.6 to 2.0 times of the rated capacity of expander. In the second stage, the expander was removed and the expanded flap (size ranging from 4.1 cm×1.8 cm to 9.1 cm×7.9 cm) was transferred to repair the wound of exposed titanium mesh. The placement site of the expander, the transfer form of the expanded flap, the postoperative wound healing of the titanium mesh exposed site, and the survival of expanded flap were recorded. The scar of the head incision and the appearance of head were followed up.Results:Among the patients in this group, the expanders of 7 were placed in the temporal region, while the other 6 were placed at the top. The 11 patients were treated with advanced expanded flap, while the other 2 patients were treated with pedicled expanded flap. The head wounds of patients in this group successfully healed with retaining of the titanium mesh. The wound was healed after dressing change in 1 patient with necrosis at the tip of the expanded flap. The expanded flaps of 12 patients survived after transfer. Patients in this group were followed up for 12 months after surgery, the exposed titanium meshes were retained, the incisions healed well with the scars concealed, the hair on the scalp grew well, and the appearance of head was comparatively good.Conclusions:Using expanded flap in the repair of the wounds with exposed titanium mesh after cranioplasty with titanium mesh can effectively cover the wound and retain the titanium mesh, achieving good function and appearance.

Objective:To compare the efficacy and safety of low energy and high energy density pulsed dye laser in treating hypertrophic scars.Methods:From January 2019 to March 2019, forty-five patients with hypertrophic scar were randomly divided into three groups with 15 cases in each group: the control group, low energy density group and high energy density group. There were 26 males and 19 females, aged from 1 to 48 years. Each patient was treated with compressive treatment and drug treatment. The patients in low energy density group were treated with 595 nm pulsed dye laser and the energy density was 4.0-6.5 J/cm 2; the patients in high energy density group were treated with 595 nm pulsed dye laser and the energy density was 6.6-9.0 J/cm 2; the patients in control group were not treated with laser. Patients were treated with pulsed dye laser once every 3-4 weeks until 6 months. Scars were scored by Vancouver scar scale (VSS) before and after treatment. Degree of satisfaction of patients and adverse reactions were also recorded. Date were processed with one-way analysis of variance, χ2 test and t test. Results:(1) VSS scores in both control group and high energy group after treatment were significantly higher than those before treatment. VSS scores in low energy group after treatment were significantly lower than those before treatment ( P<0.05); VSS score in all three groups were significantly different after treatment( P<0.05). (2) Color scores in control and high energy group after treatment were higher than those before treatment in the same group. Color scores in low energy group after treatment were lower than those before treatment( P<0.05). Color scores in these three groups were significantly different( P<0.05). (3) The satisfaction degree of patients in control group was 6.67%(1/15), 13.33%(2/15) in high energy density group and 66.67%(10/15) in low energy density group. The satisfaction degree in low energy density group is significantly higher than that in control group and high energy density group ( P<0.05). (4) The duration of erythema or purpura in low energy density group after treatment was significantly shorter than that in high energy density group( P<0.05). No patient had blister in low energy density group, compared to 10 patients in high energy density group, the cases of adverse reaction in high energy density group was significantly more than that in low energy density group. Conclusions:The low energy density pulsed dye laser in the treatment of hypertrophic scar is better than high energy density pulsed dye laser, and the incidence of adverse reactions is low. Low energy density(4.0~6.5 J/cm 2) pulsed dye laser is the recommended energy parameter for the treatment of hypertrophic scar.