OBJECTIVE: To evaluate the application of skin and soft tissue expansion in the treatment of deformity due to extensive severe burn injury and repair of severe deep electrical burned scalp and skull with fresh wound. METHODS: From 1988, 83 cases of application of skin and soft tissue expansion were reported. In those patients with deformity due to severe burn of large area and with whole nasal defect, soft tissue expander was used under the forehead skin graft and venter frontalis, followed by reconstruction of nose with the expanded vascularized skin flap and carved cartilago costalis as nasal frame. In patients of severe deep electrical burned scalp and skull with fresh wound, skin and soft tissue expansion were used to repair the wound simultaneously with scalp burn alopecia, anesthetics and antibiotics injected into the extracapsular space of the expander in case of pain and infection. RESULTS: All of the cases were successfully treated with little pain and minimized infection. CONCLUSION: Skin and soft tissue expansion in a safe and reliable measure in the treatment of deformity due to extensive severe burn injury and repair of severe deep electrical burned scalp and skull with fresh wound.
Aiming at the problem of the influence of preloading force on its mechanical response in soft tissue compression experiments, an elimination method of preloading force based on linear loading region is proposed. Unconfined compression experiments under a variety of different preloading forces are performed. The influence of the preloading force on the parameters of constitutive model is analyzed. In the preload phase, the mechanical response of the soft tissue is taken as a linear model. The preloading force is eliminated by taking the preloading phase into account throughout the response process. According to five different preloading forces of the unconfined compression experiments, the elimination method is validated with two different constitutive models of soft tissue, and the error between the models obtained by the preloading force elimination method and the traditional method with the experimental results is compared. The results show that the error obtained by preloading force elimination method is significantly smaller than the traditional method. The preloading force elimination method can eliminate the influence of preloading force on mechanical response to a certain extent, and constitutive model parameters which are closer to the true properties of soft tissue can be obtained.
Small intestinal submucosa (SIS) is a natural decellularized extracellular matrix material. Due to its excellent biocompatibility, unique biomechanical properties and biological activity, it has been widely used as a scaffold in regenerative medicine. This article reviews the recent progress in the characterization and medical application of SIS respectively. The specific biological properties of the SIS, as well as its interaction with cells, are highlighted. Some of the SIS products and clinical cases are also reviewed and discussed.
ObjectiveTo explore the possibility of constructing tissue engineered adipose by adipose tissue derived extracellular vesicles (hAT-EV) combined with decellularized adipose tissue (DAT) scaffolds, and to provide a new therapy for soft tissue defects.MethodsThe adipose tissue voluntarily donated by the liposuction patient was divided into two parts, one of them was decellularized and observed by HE and Masson staining and scanning electron microscope (SEM). Immunohistochemical staining and Western blot detection for collagen type Ⅰ and Ⅳ and laminin were also employed. Another one was incubated with exosome-removed complete medium for 48 hours, then centrifuged to collect the medium and to obtain hAT-EV via ultracentrifugation. The morphology of hAT-EV was observed by transmission electron microscopy; the nanoparticle tracking analyzer (NanoSight) was used to analyze the size distribution; Western blot was used to analyse membrane surface protein of hAT-EV. Adipose derived stem cells (ADSCs) were co-cultured with PKH26 fluorescently labeled hAT-EV, confocal fluorescence microscopy was used to observe the uptake of hAT-EV by ADSCs. Oil red O staining was used to evaluate adipogenic differentiation after hAT-EV and ADSCs co-cultured for 15 days. The DAT was scissored and then injected into the bilateral backs of 8 C57 mice (6-week-old). In experimental group, 0.2 mL hAT-EV was injected weekly, and 0.2 mL PBS was injected weekly in control group. After 12 weeks, the mice were sacrificed, and the new fat organisms on both sides were weighed. The amount of new fat was evaluated by HE and peri-lipoprotein immunofluorescence staining to evaluate the ability of hAT-EV to induce adipogenesis in vivo.ResultsAfter acellularization of adipose tissue, HE and Masson staining showed that DAT was mainly composed of loosely arranged collagen with no nucleus; SEM showed that no cells and cell fragments were found in DAT, and thick fibrous collagen bundles could be seen; immunohistochemical staining and Western blot detection showed that collagen type Ⅰ and Ⅳ and laminin were retained in DAT. It was found that hAT-EV exhibited a spherical shape of double-layer envelope, with high expressions of CD63, apoptosis-inducible factor 6 interacting protein antibody, tumor susceptibility gene 101, and the particle size of 97.9% hAT-EV ranged from 32.67 nmto 220.20 nm with a peak at 91.28 nm. Confocal fluorescence microscopy and oil red O staining showed that hAT-EV was absorbed by ADSCs and induced adipogenic differentiation. In vivo experiments showed that the wet weight of fat new organisms in the experimental group was significantly higher than that in the control group (t=2.278, P=0.048). HE staining showed that the structure of lipid droplets in the experimental group was more than that in the control group, and the collagen content in the control group was higher than that in the experimental group. The proportion of new fat in the experimental group was significantly higher than that in the control group ( t=4.648, P=0.017).ConclusionDAT carrying hAT-EV can be used as a new method to induce adipose tissue regeneration and has a potential application prospect in the repair of soft tissue defects.
Objective To evaluate short-term effectiveness of staged management for complex tibial plateau fracture with severe soft tissue injury. Methods A clinical data of 12 patients with complex tibial plateau fractures and severe soft tissue injuries between July 2017 and March 2021 and met the selection criteria was retrospectively analyzed. There were 7 males and 5 females with an average age of 43.1 years (range, 33-58 years). All patients were traffic accident injuries and admitted to hospital within 24 hours after injury. The tibial plateau fractures were closed fractures. According to the Schatzker classification standard, the fractures were rated as type Ⅳ in 3 cases, type Ⅴ in 4 cases, and type Ⅵ in 5 cases. According to the Tscherne classification standard, the soft tissue injuries were rated as grade Ⅱ in 4 cases and grade Ⅲ in 8 cases. The treatment of all patients was divided into 3 stages. In the first stage, emergency trans-articular fracture fixation with external fixator was performed; in the second stage, the fracture reduction and internal fixation were performed and bone cement was implanted to fill the bone defect; in the third stage, the bone cement was removed and the bone graft was performed to repair defect. All patients performed joint function exercise after operation as early as possible. Results There was no neurological symptom after all staged managements, the incisions healed by first intention, and no complications such as incision infection or necrosis occurred. All patients were followed up 6-32 months (mean, 16.9 months). The fractures were all anatomical reduction confirmed by the X-ray films after operation. During follow-up, there was no obvious loss of reduction, loosening and rupture of internal fixator, or collapse of the articular surface. All fractures healed after 14-20 weeks (mean, 17.6 weeks). The posterior slope angle of the tibial plateau was (9.7±2.3)° and the varus angle was (3.9±1.9)° immediately after bone grafting, and were (8.5±2.9)° and (4.3±1.9)° respectively at 6 months after operation. There was no significant difference between the two time points (t=0.658, P=0.514; t=?1.167, P=0.103). At last follow-up, the Hospital for Special Surgery (HSS) score was 85-96 (mean, 91.2), and the range of motion of knee was 110°-135° (mean, 120.9°). Conclusion The staged management for complex tibial plateau fracture with severe soft tissue injury can obtain good short-term effectiveness, but the long-term effectiveness needs to be further followed up.
ObjectiveTo investigate the effectiveness of soft tissue balance technique by flexor pollicis longus (FPL) tendon transfer for Wassel Ⅳ-D thumb duplication in children. Methods A clinical data of 14 children with Wassel Ⅳ-D thumb duplication met the selection criteria between January 2017 and January 2021 was retrospectively analyzed. There were 5 boys and 9 girls with an average age of 21.6 months (range, 18-35 months). Ten cases were left hand deformity and 4 cases were right hand deformity. During operation, the radial thumb was excised, and the FPL tendon of the radial thumb was used to reconstruct the soft tissue balance of the ulnar thumb. Postoperative evaluation included the range of motion (ROM) of passive flexion and extension of the interphalangeal joint (IP) and metacarpophalangeal joint (MCP), the alignments of the IP and MCP, the percentage of the width of the nail plate and the circumference of the thumb at the level of the IP to contralateral thumb. Results All operations were completed successfully, and all incisions healed by first intention. The children were followed up 12-36 months (mean, 21.7 months). At last follow-up, the ROM of passive flexion and the deviation of the IP, and the deviation of the MCP significantly improved when compared with those before operation (P<0.05); the ROM of passive extension of the IP and the ROM of passive flexion of the MCP did not significantly improve when compared with those before operation (P>0.05). The ROMs of passive extension of the MCP were 0° before and after operation. The width of the nail plate was 76.6%±4.1% of the unaffected side, and the circumference of the thumb at the level of the IP was 92.0%±9.1% of the unaffected side. ConclusionThe soft tissue balance technique by FPL tendon trasfer can effectively correct the alignment of the Wassel Ⅳ-D thumb duplication in children, and maintain the correction effect effectively, but further follow-up and comprehensive evaluation are needed to investigate the long-term effectiveness.
Objective To explore an improved method of reconstructing the scalp soft tissue defect with the expanded skin soft tissue and treating and preventing the related complication. Methods From October 2002 toJune 2005, 32 patients (20 males and 12 females, aged 5-48 years) underwent reconstruction of the scalp soft tissue defects with the expanded scalp soft tissue in thetwo-stage operation. In the first stage, a tissue expander (cylindrical form, 50-250 ml) was inplanted into the skin to achieve a skin soft tissue expansion. After a sufficient skin expansion (8 cm×5 cm to 25 cm×23 cm) was made by the routine water affusion for 6-16 weeks, a properly-designed skin flap was taken and transferred to reconstruct the scalp soft tissue defect in the second-stage of the operation. All the scalp defects were left after the resections of the scalp lesions, which ranged in size from 7 cm×5 cm to 20 cm×20 cm.Results After operation, all the 32 patients had their scalp defects repaired and reconstructed well.The expanded skin flaps of all the 32 patients survived except 1 patient who had a necrosis of the distal epidermis of the flap, which healed after the dressings of the wound. The hair grew well and the scars were hidden with a satisfactory appearance. Four patients developed complications (necrosis of the distal flapin 1 patient, hematoma in 1, expander exposure in 1, and wound rupture in 1).Conclusion Reconstruction of the scalp soft tissue defect with the skin soft tissue expansion is an ideal method.
Objective
To explore the effectiveness of modified anterolateral thigh perforator flap pedicled by cross-bridge microvascular anastomosis in treatment of soft tissue defects in the middle and lower segments of the leg.
Methods
Between March 2011 and June 2015, 15 cases with skin and soft tissue defects in the middle and lower segments of the legs were treated. There were 9 males and 6 females, aged 22-48 years (mean, 32.6 years). Of whom, 8 patients caused by traffic accidents, 5 by machine twist, and 2 by crash injury of heavy object. The mean interval from injury to admission was 82.6 hours (range, 2 hours to 1 week). The area of defect ranged from 13 cm×9 cm to 23 cm×16 cm. After primary debridement and vaccum sealing drainage treatment, the defects were repaired with modified anterolateral thigh perforator flap pedicled by cross-bridge microvascular anastomosis. The size of flap ranged from 15 cm×10 cm to 25 cm×15 cm. The donor sites were sutured directly or repaired with the skin grafts. The pedicle division was done at 4 weeks after operation.
Results
After operation, venous crisis occurred in 1 case and distal skin necrosis in 2 cases which was healed by dressing change. The other tissue flaps survived successfully and wounds healed by first intention. All skin grafts at donor site survived after operation, and primary healing of wound was obtained. All patients were followed up 6-24 months (mean, 13 months). All flaps were characterized by soft texture, satisfactory appearance, and restoring the protective sensation. Moreover, the two-point discrimination ranged from 15 to 28 mm (mean, 19.5 mm) at 6 months after operation. The function of both lower extremities were normal without obvious contracture of scar at donor site.
Conclusion
Modified free anterolateral thigh perforator flap, with little damage in donor site, a reliable blood supply by making a cross-bridge microvascular anastomosis with pretibial or posterior tibial blood vessel on normal leg, is a reliable alternative method for repairing soft tissue defects with the main vessels of serious injury in the middle and lower segments of the leg.
The mechanical behavior modeling of human soft biological tissues is a key issue for a large number of medical applications, such as surgery simulation, surgery planning, diagnosis, etc. To develop a biomechanical model of human soft tissues under large deformation for surgery simulation, the adaptive quasi-linear viscoelastic (AQLV) model was proposed and applied in human forearm soft tissues by indentation tests. An incremental ramp-and-hold test was carried out to calibrate the model parameters. To verify the predictive ability of the AQLV model, the incremental ramp-and-hold test, a single large amplitude ramp-and-hold test and a sinusoidal cyclic test at large strain amplitude were adopted in this study. Results showed that the AQLV model could predict the test results under the three kinds of load conditions. It is concluded that the AQLV model is feasible to describe the nonlinear viscoelastic properties of in vivo soft tissues under large deformation. It is promising that this model can be selected as one of the soft tissues models in the software design for surgery simulation or diagnosis.
ObjectiveTo investigate the effectiveness of relay flap on repairing skin and soft tissue defect of auricle and donor site. MethodsBetween May 2014 and January 2016, 10 patients with auricular tumor were repaired by relay flap. There were 4 males and 6 females with an average age of 35 years (range, 21-69 years). There were basal cell carcinoma in 2 cases, pigmented nevus in 3 cases, papilloma in 4 cases, and Bowen’s disease in 1 case. The size of the residual wound after tumor resection ranged from 1.1 cm×1.0 cm to 2.3 cm×1.7 cm. The superficial temporal artery posterior auricular perforator flap was used to repair the auricle defect wound. The size of flap ranged from 1.5 cm×1.4 cm to 2.8 cm×2.0 cm. The first donor site was repaired with the posterior auricular artery perforator propulsive flap. The size of flap ranged from 4.0 cm×2.0 cm to 7.5 cm×3.0 cm. The wound of the second donor site was sutured directly at the first stage. ResultsAll the flaps survived. The donor and recipient sites healed by first intention. The patients were followed up 10-28 months, with an average of 14.2 months. The appearance of reconstructed auricle was satisfactory, and the tumor had no recurrence. The appearance, color, texture, and thickness of the flaps were basically consistent with the recipient site, without obvious scar, traction deformity, or obvious abnormal sensation. ConclusionThe relay flap has advantages of reliable blood supply, the simple operation method, the concealed donor site, which is a good choice to repair the skin and soft tissue defect of auricle and donor site.
