Objective:To explore the effect of self-made static progressive braces in the stepwise treatment of hand flexion dysfunction caused by scar contracture after burn injury.Methods:This study was a retrospective observational study. From January 2022 to March 2024, the First Affiliated Hospital of Air Force Medical University admitted twenty-nine patients who met the inclusion criteria and used the self-made static progressive braces for stepwise treatment of hand flexion dysfunction caused by scar contracture, including 23 males and 6 females, aged 16 to 55 years. The depth of burn on the back of the hand was deep partial-thickness to full-thickness. The self-made static progressive brace referred to the self-made static progressive joint distractor and the self-made static progressive hand flexion distractor. The stepwise treatment was adopted. In the first stage, in-hospital treatment for 2 to 4 weeks was selected. The treatment contents included conventional rehabilitation training and training on the application of the self-made joint distractors. When the active flexion range of motion of the metacarpophalangeal joint was ≥60°, the second stage of treatment was carried out, that is, two weeks of home remote rehabilitation treatment. The treatment contents included individualized exercise training such as training with self-made static progressive joint distractors and training with self-made static progressive hand flexion distractors. Adverse events such as blister, brace compression, and tissue strain during the stepwise treatment were recorded. After the end of the stepwise treatment, the active flexion of the affected hand was observed. During follow-up, the total active range of motion of the affected hand was measured, and the extensibility of the scar and skin and soft tissue on the back of the affected hand and the patient's satisfaction with the therapeutic effect were evaluated. At the last follow-up, the function of the affected hand was evaluated according to the trial standards for evaluation of partial function of upper extremity by the Hand Surgery Society of Chinese Medical Association.Results:During the stepwise treatment, a small amount of blisters developed on the skin at the wrist joint in 2 patients, which was cured after symptomatic treatment; the other patients had no adverse events such as brace compression and tissue strain. After the end of the stepwise treatment, the active flexion function of the hand was better, and the fist could be basically clenched. After 1-3 months of follow-up, the total active range of motion of the affected hand was 200-245°; the scar on the back of the hand was soft and light-colored, and the skin and soft tissue was malleable. Twenty-two patients were very satisfied with the curative effect, 6 patients were satisfied, and 1 patient was dissatisfied. At the last follow-up, there were 20 cases with excellent hand function and 9 cases with good hand function.Conclusions:The stepwise treatment of hand flexion dysfunction caused by scar contracture after burn injury with self-made static progressive braces has a good effect and few complications. Moreover, the two self-made static progressive distractors are convenient in material acquisition, simple to make, cost-effective, and highly practical, which is worthy of clinical promotion.

Objective:To explore the effect of self-made static progressive braces in the stepwise treatment of hand flexion dysfunction caused by scar contracture after burn injury.Methods:This study was a retrospective observational study. From January 2022 to March 2024, the First Affiliated Hospital of Air Force Medical University admitted twenty-nine patients who met the inclusion criteria and used the self-made static progressive braces for stepwise treatment of hand flexion dysfunction caused by scar contracture, including 23 males and 6 females, aged 16 to 55 years. The depth of burn on the back of the hand was deep partial-thickness to full-thickness. The self-made static progressive brace referred to the self-made static progressive joint distractor and the self-made static progressive hand flexion distractor. The stepwise treatment was adopted. In the first stage, in-hospital treatment for 2 to 4 weeks was selected. The treatment contents included conventional rehabilitation training and training on the application of the self-made joint distractors. When the active flexion range of motion of the metacarpophalangeal joint was ≥60°, the second stage of treatment was carried out, that is, two weeks of home remote rehabilitation treatment. The treatment contents included individualized exercise training such as training with self-made static progressive joint distractors and training with self-made static progressive hand flexion distractors. Adverse events such as blister, brace compression, and tissue strain during the stepwise treatment were recorded. After the end of the stepwise treatment, the active flexion of the affected hand was observed. During follow-up, the total active range of motion of the affected hand was measured, and the extensibility of the scar and skin and soft tissue on the back of the affected hand and the patient's satisfaction with the therapeutic effect were evaluated. At the last follow-up, the function of the affected hand was evaluated according to the trial standards for evaluation of partial function of upper extremity by the Hand Surgery Society of Chinese Medical Association.Results:During the stepwise treatment, a small amount of blisters developed on the skin at the wrist joint in 2 patients, which was cured after symptomatic treatment; the other patients had no adverse events such as brace compression and tissue strain. After the end of the stepwise treatment, the active flexion function of the hand was better, and the fist could be basically clenched. After 1-3 months of follow-up, the total active range of motion of the affected hand was 200-245°; the scar on the back of the hand was soft and light-colored, and the skin and soft tissue was malleable. Twenty-two patients were very satisfied with the curative effect, 6 patients were satisfied, and 1 patient was dissatisfied. At the last follow-up, there were 20 cases with excellent hand function and 9 cases with good hand function.Conclusions:The stepwise treatment of hand flexion dysfunction caused by scar contracture after burn injury with self-made static progressive braces has a good effect and few complications. Moreover, the two self-made static progressive distractors are convenient in material acquisition, simple to make, cost-effective, and highly practical, which is worthy of clinical promotion.

Purpose: This study explored the association of the elasticity modulus and shear wave velocity (SWV) of the tibialis anterior muscle, as measured by two-dimensional shear wave elastography (2D-SWE), with the intracompartmental pressure (ICP) determined using the Whitesides method in a New Zealand rabbit model of acute compartment syndrome (ACS). Additionally, it evaluated the viability of 2D-SWE as a noninvasive, quantitative tool for the early detection of ACS. Methods: An ACS model was established through direct external compression by applying pressure bandaging to the lower legs of 15 New Zealand rabbits using neonatal blood pressure cuffs. Another five animals represented a non-modeled control group. To measure the elasticity modulus and SWV of the tibialis anterior muscles, 2D-SWE was employed. Blood oxygen saturation, serum creatine kinase (CK), and myoglobin levels were monitored. Subsequently, the anterior tibial compartment was dissected, and the tibialis anterior was removed for hematoxylin and eosin staining to assess muscle injury. Results: The elasticity modulus and SWV of the tibialis anterior muscle increased with compression duration, as did serum CK and myoglobin levels. ICP was strongly positively correlated with these parameters, particularly mean velocity (r=0.942, P<0.001) and CK (r=0.942, P<0.001). Blood oxygen saturation was negatively correlated with ICP (r=-0.887, P<0.001). Histological analysis indicated progressive muscle cell swelling over time, with damage transitioning from reversible to irreversible and culminating in necrosis. Conclusion In a rabbit ACS model, ICP was strongly positively correlated with muscle elasticity modulus/SWV. Consequently, 2D-SWE may represent a novel tool for assessing early-phase ACS.

Purpose: This study explored the association of the elasticity modulus and shear wave velocity (SWV) of the tibialis anterior muscle, as measured by two-dimensional shear wave elastography (2D-SWE), with the intracompartmental pressure (ICP) determined using the Whitesides method in a New Zealand rabbit model of acute compartment syndrome (ACS). Additionally, it evaluated the viability of 2D-SWE as a noninvasive, quantitative tool for the early detection of ACS. Methods: An ACS model was established through direct external compression by applying pressure bandaging to the lower legs of 15 New Zealand rabbits using neonatal blood pressure cuffs. Another five animals represented a non-modeled control group. To measure the elasticity modulus and SWV of the tibialis anterior muscles, 2D-SWE was employed. Blood oxygen saturation, serum creatine kinase (CK), and myoglobin levels were monitored. Subsequently, the anterior tibial compartment was dissected, and the tibialis anterior was removed for hematoxylin and eosin staining to assess muscle injury. Results: The elasticity modulus and SWV of the tibialis anterior muscle increased with compression duration, as did serum CK and myoglobin levels. ICP was strongly positively correlated with these parameters, particularly mean velocity (r=0.942, P<0.001) and CK (r=0.942, P<0.001). Blood oxygen saturation was negatively correlated with ICP (r=-0.887, P<0.001). Histological analysis indicated progressive muscle cell swelling over time, with damage transitioning from reversible to irreversible and culminating in necrosis. Conclusion In a rabbit ACS model, ICP was strongly positively correlated with muscle elasticity modulus/SWV. Consequently, 2D-SWE may represent a novel tool for assessing early-phase ACS.

Purpose: This study explored the association of the elasticity modulus and shear wave velocity (SWV) of the tibialis anterior muscle, as measured by two-dimensional shear wave elastography (2D-SWE), with the intracompartmental pressure (ICP) determined using the Whitesides method in a New Zealand rabbit model of acute compartment syndrome (ACS). Additionally, it evaluated the viability of 2D-SWE as a noninvasive, quantitative tool for the early detection of ACS. Methods: An ACS model was established through direct external compression by applying pressure bandaging to the lower legs of 15 New Zealand rabbits using neonatal blood pressure cuffs. Another five animals represented a non-modeled control group. To measure the elasticity modulus and SWV of the tibialis anterior muscles, 2D-SWE was employed. Blood oxygen saturation, serum creatine kinase (CK), and myoglobin levels were monitored. Subsequently, the anterior tibial compartment was dissected, and the tibialis anterior was removed for hematoxylin and eosin staining to assess muscle injury. Results: The elasticity modulus and SWV of the tibialis anterior muscle increased with compression duration, as did serum CK and myoglobin levels. ICP was strongly positively correlated with these parameters, particularly mean velocity (r=0.942, P<0.001) and CK (r=0.942, P<0.001). Blood oxygen saturation was negatively correlated with ICP (r=-0.887, P<0.001). Histological analysis indicated progressive muscle cell swelling over time, with damage transitioning from reversible to irreversible and culminating in necrosis. Conclusion In a rabbit ACS model, ICP was strongly positively correlated with muscle elasticity modulus/SWV. Consequently, 2D-SWE may represent a novel tool for assessing early-phase ACS.

Purpose: This study explored the association of the elasticity modulus and shear wave velocity (SWV) of the tibialis anterior muscle, as measured by two-dimensional shear wave elastography (2D-SWE), with the intracompartmental pressure (ICP) determined using the Whitesides method in a New Zealand rabbit model of acute compartment syndrome (ACS). Additionally, it evaluated the viability of 2D-SWE as a noninvasive, quantitative tool for the early detection of ACS. Methods: An ACS model was established through direct external compression by applying pressure bandaging to the lower legs of 15 New Zealand rabbits using neonatal blood pressure cuffs. Another five animals represented a non-modeled control group. To measure the elasticity modulus and SWV of the tibialis anterior muscles, 2D-SWE was employed. Blood oxygen saturation, serum creatine kinase (CK), and myoglobin levels were monitored. Subsequently, the anterior tibial compartment was dissected, and the tibialis anterior was removed for hematoxylin and eosin staining to assess muscle injury. Results: The elasticity modulus and SWV of the tibialis anterior muscle increased with compression duration, as did serum CK and myoglobin levels. ICP was strongly positively correlated with these parameters, particularly mean velocity (r=0.942, P<0.001) and CK (r=0.942, P<0.001). Blood oxygen saturation was negatively correlated with ICP (r=-0.887, P<0.001). Histological analysis indicated progressive muscle cell swelling over time, with damage transitioning from reversible to irreversible and culminating in necrosis. Conclusion In a rabbit ACS model, ICP was strongly positively correlated with muscle elasticity modulus/SWV. Consequently, 2D-SWE may represent a novel tool for assessing early-phase ACS.

Objective To investigate the therapeutic effect of pectoralis major muscle flap combined with negative pressure lavage in one-stage repair of refractory wounds after thoracotomy.Methods From January 2020 to January 2023,21 patients with refractory wounds after thoracotomy were retrospectively selected from the First Affiliated Hospital of Air Force Military Medical University,including 16 males and 5 females,aged 35 to 75 years old,with an average age of(62.2±11.3)years old.The wound area was 6cm×3cm to 25cm×5cm.The infected sternum was removed.According to the location and size of the residual cavity,the pectoralis major muscle of the corresponding segment on both sides of the free wound was sutured and filled.The irrigation tube was reserved below the muscle flap.After the muscle flap covered the residual cavity,the skin around the wound was sutured without tension,and the negative pressure suction of-30 to-20 kPa was given.From the first day after operation,physiological saline was used for lavage,2000ml per day.The character,color and amount of lavage fluid and the systemic symptoms of patients were observed.After the lavage fluid was clear,the tube and the negative pressure device were removed.The wound was changed once every other day,and the stitches were removed 2 weeks after operation.Results Nineteen patients achieved primary healing within 14 days after operation.Two patients had scattered wounds of about 1 cm×1 cm in size,and continued dressing change.All patients healed one month after operation.The patients were followed up for half a year to 2 years.The patient's chest shape was beautiful.There was no effect on the activity of the forebody and upper limbs,and there was no significant change in the muscle strength of the upper limbs.Conclusion For the refractory wounds after thoracotomy,after removing the infected sternum,using the pectoralis major muscle flap combined with negative pressure lavage to close the wound in one stage can reduce the risk of wound infection and death,shorten the hospital stay of patients,and the operation is simple and the trauma to patients is less.

Purpose: This study explored the association of the elasticity modulus and shear wave velocity (SWV) of the tibialis anterior muscle, as measured by two-dimensional shear wave elastography (2D-SWE), with the intracompartmental pressure (ICP) determined using the Whitesides method in a New Zealand rabbit model of acute compartment syndrome (ACS). Additionally, it evaluated the viability of 2D-SWE as a noninvasive, quantitative tool for the early detection of ACS. Methods: An ACS model was established through direct external compression by applying pressure bandaging to the lower legs of 15 New Zealand rabbits using neonatal blood pressure cuffs. Another five animals represented a non-modeled control group. To measure the elasticity modulus and SWV of the tibialis anterior muscles, 2D-SWE was employed. Blood oxygen saturation, serum creatine kinase (CK), and myoglobin levels were monitored. Subsequently, the anterior tibial compartment was dissected, and the tibialis anterior was removed for hematoxylin and eosin staining to assess muscle injury. Results: The elasticity modulus and SWV of the tibialis anterior muscle increased with compression duration, as did serum CK and myoglobin levels. ICP was strongly positively correlated with these parameters, particularly mean velocity (r=0.942, P<0.001) and CK (r=0.942, P<0.001). Blood oxygen saturation was negatively correlated with ICP (r=-0.887, P<0.001). Histological analysis indicated progressive muscle cell swelling over time, with damage transitioning from reversible to irreversible and culminating in necrosis. Conclusion In a rabbit ACS model, ICP was strongly positively correlated with muscle elasticity modulus/SWV. Consequently, 2D-SWE may represent a novel tool for assessing early-phase ACS.

Objective:To investigate the perioperative management of wounds associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy, and to evaluate its clinical effects.Methods:This study was a retrospective observational study. From January 2017 to December 2022, 36 patients with wounds associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy who were conformed to the inclusion criteria were admitted to the Burn Center of PLA of the First Affiliated Hospital of Air Force Medical University, including 23 males and 13 females, aged 25 to 81 years. Preparation for surgery was made. For patients with suspected retrosternal mediastinal abscess cavity, all cancellous bone of the unhealed sternum was bitten off to fully expose the retrosternal mediastinum, remove the source of infection and granulation tissue, and to fill the sternum defect with flipped unilateral pectoralis major muscle. For patients who had no retrosternal mediastinal infection but had fresh granulation tissue in unhealed sternal wounds, the necrotic tissue and a small amount of necrotic sternum were palliatively removed, and bilateral pectoralis major muscles were advanced and abutted to cover the sternal defect. After the skin in the donor area was closed by tension-relieving suture, continuous vacuum sealing drainage was performed, and continuous even infusion and lavage were added 24 hours later. The thorax was fixed with an armor-like chest strap, the patients were guided to breathe abdominally, with both upper limbs fixed to the lateral chest wall using a surgical restraint strap. The bacterial culture results of wound exudation specimens on admission were recorded. The wound condition observed during operation, debridement method, muscle flap covering method, intraoperative bleeding volume, days of postoperative infusion and lavage, lavage solution volume and changes on each day, and postoperative complications and wound healing time were recorded. After discharge, the wound healing quality, thorax shape, and mobility functions of thorax and both upper limbs were evaluated during follow-up. The stability and closure of sternum were observed by computed tomography (CT) reexamination.Results:On admission, among 36 patients, 33 cases were positive and 3 cases were negative in bacterial culture results of wound exudation specimens. Intraoperative observation showed that 26 patients had no retrosternal mediastinal infection but had fresh granulation tissue in unhealed sternal wounds, palliative debridement was performed and bilateral pectoralis major muscles were advanced and abutted to cover the defect. In 10 patients with suspected retrosternal mediastinal abscess cavity, the local sternum was completely removed by bite and the defect was covered using flipped unilateral pectoralis major muscle. During the operation, one patient experienced an innominate vein rupture and bleeding of approximately 3 000 mL during mediastinal exploration, and the remaining patients experienced bleeding of 100-1 000 mL. Postoperative infusion and lavage were performed for 4-7 days, with a lavage solution volume of 3 500-4 500 mL/d. The lavage solution gradually changed from dark red to light red and finally clear. Except for 1 patient who had suture rupture caused by lifting the patient under the armpit during nursing on the 3 rd day after surgery, the wounds of the other patients healed smoothly after surgery, and the wound healing time of all patients was 7-21 days. Follow-up for 3 to 9 months after discharge showed that the patient who had suture rupture caused by armpit lifting died due to multiple organ failure. In 1 patient, the armor-like chest strap was removed 2 weeks after surgery, and the shoulder joint movement was not restricted, resulting in local rupture of the suture, which healed after dressing change. The wounds of the remaining patients healed well, and they resumed their daily life. The local skin of patient's pectoralis major muscle defect was slightly sunken and lower than that of the contralateral thorax in the patients undergoing treatment of pectoralis major muscle inversion, while no obvious thoracic deformity was observed in patients undergoing treatment with pectoralis major muscle propulsion and abutment. The chest and upper limb movement in all patients were slightly limited or normal. CT reexamination results of 10 patients showed that the sternum was stable, the local sternum was closed or covered completely with no lacuna or defects. Conclusions:Once the wound associated with secondary sternal osteomyelitis and/or mediastinitis after sternotomy is formed, individualized and precise debridement should be performed as soon as possible, different transfer ways of pectoralis major muscle flap should be chosen to cover the defect, and postoperative continuous infusion and lavage together with strict thorax and shoulder joint restraint and immobilization should be performed. This treatment strategy can ensure good wound healing without affecting the shape and function of the donor area.

Objective:To investigate the influences and mechanism of extracellular vesicles from dermal papilla cells (DPC-EVs) of mice on human hypertrophic scar fibroblasts (HSFs).Methods:The study was an experimental research. The primary dermal papilla cells (DPCs) of whiskers were extracted from 10 6-week-old male C57BL/6J mice and identified successfully. The DPC-EVs were extracted from the 3 rd to 5 th passage DPCs by ultracentrifugation, and the morphology was observed through transmission electron microscope and the particle diameter was detected by nanoparticle tracking analyzer ( n=3) at 24 h after culture. The 3 rd passage of HSFs were divided into DPC-EV group and phosphate buffer solution (PBS) group, which were cultured with DPC-EVs and PBS, respectively. The cell scratch test was performed and cell migration rate at 24 h after scratching was calculated ( n=5). The cell proliferation levels at 0 (after 12 h of starvation treatment and before adding DPC-EVs or PBS), 24, 48, 72, and 96 h after culture were detected by using cell counting kit 8 ( n=4). The protein expressions of α-smooth muscle actin (α-SMA) and collagen typeⅠ (ColⅠ) in cells at 24 h after culture were detected by immunofluorescence method and Western blotting, and the protein expression of Krüppel-like factor 4 (KLF4) in cells at 24 h after culture was detected by Western blotting. After the 3 rd passage of HSFs were cultured with DPC-EVs for 24 h, the cells were divided into blank control group, KLF4 knockdown group, and KLF4 overexpression group according to the random number table. The cells in blank control group were only routinely cultured for 48 h. The cells in KLF4 knockdown group and KLF4 overexpression group were incubated with KLF4 knockdown virus for 24 h, then the cells in KLF4 knockdown group were routinely cultured for 24 h while the cells in KLF4 overexpression group were incubated with KLF4 overexpression virus for 24 h. The protein expressions of KLF4, α-SMA, and ColⅠ in cells were detected by Western blotting at 48 h after culture. Results:At 24 h after culture, the extracted DPC-EVs showed vesicular structure with an average particle diameter of 108.8 nm. At 24 h after scratching, the migration rate of HSFs in PBS group was (54±10)%, which was significantly higher than (29±8)% in DPC-EV group ( t=4.37, P<0.05). At 48, 72, and 96 h after culture, the proliferation levels of HSFs in DPC-EV group were significantly lower than those in PBS group (with t values of 4.06, 5.76, and 6.41, respectively, P<0.05). At 24 h after culture, the protein expressions of α-SMA and ColⅠ of HSFs in DPC-EV group were significantly lower than those in PBS group, while the protein expression of KLF4 was significantly higher than that in PBS group. At 48 h after culture, compared with those in blank control group, the protein expression of KLF4 of HSFs in KLF4 knockdown group was down-regulated, while the protein expressions of α-SMA and ColⅠ were both up-regulated; compared with those in KLF4 knockdown group, the protein expression of KLF4 of HSFs in KLF4 overexpression group was up-regulated, while the protein expressions of ColⅠ and α-SMA were down-regulated. Conclusions:The DPC-EVs of mice can inhibit the proliferation and migration of human HSFs and significantly inhibit the expressions of fibrosis markers α-SMA and ColⅠ in human HSFs by activating KLF4.