ObjectiveTo investigate the effectiveness of distraction therapy assisted by arthroscope in the treatment of ankle traumatic osteoarthritis. MethodsBetween October 2013 and October 2014, 13 patients with ankle traumatic osteoarthritis were treated, including 8 males and 5 females with an age range of 44-63 years (mean, 55.2 years). The left ankle and the right ankle were involved in 4 and 9 cases respectively. The disease duration was 1.5-10.0 years (median, 5 years). The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hind foot scale score was 51.00±7.09; the short-form 36 health survey scale (SF-36) score was 40.82±4.62. According to Scranton grade system, 9 cases were rated as grade II and 4 cases as grade III. First, ankle hyperplasia osteophytes was removed under arthroscope, then Ilizarov apparatus was used to maintain distraction of 5-10 mm ankle space for 3 months. ResultsOne case had postoperative pin tract infection after removing the external fixation, and infection was controlled by dressing treatment; no related complications occurred in the other patients. All patients got follow-up of 12-18 months (mean, 14.7 months). Patients achieved disappearance of ankle swelling, pain relief, and were able to walk after rehabilitation. The ankle activity was obviously improved. At last follow-up, AOFAS ankel-hind foot scale score and SF-36 score were significantly increased to 85.23±6.41 and 56.29±6.20 respectively (t=20.756, P=0.025; t=11.647, P=0.018). According to AOFAS scores, the results were excellent in 4 cases, good in 8 cases, and fair in 1 case; the excellent and good rate was 92.3%. Postoperative X-ray film showed normal ankle position and alignment, osteophytes at the edges of the tibia and talus, articular surface sclerosis, normal joint space, and no joint swelling. ConclusionDistraction therapy assisted by arthroscope is an effective method for treating ankle traumatic osteoarthritis.
ObjectiveTo summarize the effectiveness of delayed skin-stretching device in treatment of skin and soft tissue defects.MethodsBetween December 2014 and December 2016, 10 cases of skin and soft tissue defects were treated with delayed skin-stretching device. There were 6 males and 4 females with an average age of 53 years (range, 42-64 years). The skin and soft tissue defects were caused by acute trauma in 6 cases. The incision could not be closed directly after making incisions because of osseous fascia syndrome in 3 cases. The skin soft tissue defect caused after huge carbuncle incision and drainage in 1 case. The defect located at thigh in 4 cases, lower leg in 3 cases, upper arm in 2 cases, back in 1 case. The defect area ranged from 10 cm×4 cm to 22 cm×12 cm. Pinch test was performed on the wound margin, which confirmed that the wound could not be closed directly.ResultsTension blisters were found in 3 cases during traction, and no complications such as impaired blood circulation or skin necrosis occurred in all cases. Skin defects closed directly after continuously stretching for 7-18 days. No skin graft or free flap repair was performed in all patients. The wound healed well after operation. All the 10 patients were followed up 5-8 months (mean, 6.5 months). There was no necrosis around the wound margin and the scar was linear. The sensation and function were not affected.ConclusionDelayed skin-stretching device is an effective method to treat skin and soft tissue defects, which has the advantages of simple operation, lower risk of operation, less complications, and reliable effectiveness.
Idiopathic pulmonary fibrosis (IPF) is a progressive scar-forming disease with a high mortality rate that has received widespread attention. Epithelial mesenchymal transition (EMT) is an important part of the pulmonary fibrosis process, and changes in the biomechanical properties of lung tissue have an important impact on it. In this paper, we summarize the changes in the biomechanical microenvironment of lung tissue in IPF-EMT in recent years, and provide a systematic review on the effects of alterations in the mechanical microenvironment in pulmonary fibrosis on the process of EMT, the effects of mechanical factors on the behavior of alveolar epithelial cells in EMT and the biomechanical signaling in EMT, in order to provide new references for the research on the prevention and treatment of IPF.
Objective To investigate the technique of reduction by posterior approach for severe spondylolisthesis, and to discuss the method to prevent nerve stretch injury. Methods Between July 2007 and April 2011, 17 patients with severe spondylolisthesis underwent reduction, fixation, and fusion by posterior approach. There were 2 males and 15 females with a median age of 15 years (range, 8-67 years) and a median disease duration of 18 months (range, 5 months-16 years and 4 months). The level of spondylolisthesis was at L4 in 1 case and L5 in 16 cases; the spondylolisthesis was at degree III in 12 cases and degree IV in 5 cases according to Meyerding classification. There were 16 cases of developmental spondylolisthesis (high- dysplastic and low-dysplasia spondylolisthesis in 9 and 7 cases, respectively) and 1 case of traumatic spondylolisthesis; 16 cases of developmental spondylolisthesis at L5 level included 6 cases of type 4, 9 case of type 5, and 1 case of type 6 according to Spinal Deformity Study Group (SDSG) classification. All cases underwent posterior spinal decompression, Schanz screw fixation for the slipped vertebrae, the intervertebral and posterolateral fusion and reduction of the slipped vertebrae, and correction of the lumbosacral kyphosis. The reductive degree of slipped vertebrae was modulated according to the strain of exiting spinal root. The slip degree should be reduced within Meyerding degree II. The anteroposterior and lateral radiographs of whole spine were taken in a standardized standing position to observe the correction of displacement severity and lumbosacral angle. The nerve function and pain score of lower extremity were evaluated by neurological Frankel grade and visual analogue scale (VAS). Bony fusion was assessed by followed-up CT three-dimentional reconstruction. Results Exiting nerve root paralysis occurred in 1 case after operation, and released at 4 weeks after operation; no aggravation of nerve damage was observed in the other patients. The incisions primarily healed. All the patients were followed up 12-48 months (mean, 25 months). The slip percentage, the lumbosacral angle, and VAS score of lower extremity were improved from 72% ± 10%, (18.2 ± 3.5)°, and 7.0 ± 1.5 at preoperation to 12% ± 6%, ( — 7.3 ± 2.9)°, and 1.5 ± 1.3 at 12 months after operation respectively, all showing significant differences (P lt; 0.05). Osteosynthesis was seen at the bone grafting area by CT three-dimentional reconstruction at 12 months after operation. No breakage of screw and rod or reduction loss occurred. Conclusion It can obtain satisfactory clinical result to use spinal canal decompression by posterior approach, the Schanz screw fixation of the slipped vertebrae, the intervertebral and posterolateral fusion for severe spondylolisthesis. The risk of nerve stretch injury can be prevented by choosing the lowest height of intervertebral cage, modulating the reductive degree of slipped vertebrae according to the strain of exiting spinal root, and correcting lumbosacral kyphosis.
Objective To investigate the effects of different mechanical stretch conditions on the differentiation of rat tendon stem cells (TSCs), to find the best uniaxial cyclic stretching for TSCs tenogenic differentiation, osteogenic differentiation, and adipogenic differentiation. Methods TSCs were isolated from the Achilles tendons of 8-week-old male Sprague Dawley rats by enzymatic digestion method and cultured. The TSCs at passage 3 were randomly divided into 5 groups: group A (stretch strength of 4% and frequency of 1 Hz), group B (stretch strength of 4% and frequency of 2 Hz), group C (stretch strength of 8% and frequency of 1 Hz), group D (stretch strength of 8% and frequency of 2 Hz), and group E (static culture). At 12, 24, and 48 hours after mechanical stretch, the mRNA expressions of the tenogenic differentiation related genes [Scleraxis (SCX) and Tenascin C (TNC)], the osteogenic differentiation related genes [runt related transcription factor 2 (RUNX2) and distal-less homeobox 5 (DLX5)], and the adipogenic differentiation related genes [CCAAT-enhancer-binding protein-α (CEBPα) and lipoprteinlipase (LPL)] were detected by real-time fluorescent quantitative PCR and the protein expressions of TNC, CEBPα, and RUNX2 were detected by Western blot. Results The mRNA expressions of SCX and TNC in group B were significantly higher than those in groups A, C, D, and E at 24 hours after mechanical stretch (P<0.05). The mRNA expressions of CEBPα and LPL in group D were significantly higher than those in groups A, B, C, and E at 48 hours after mechanical stretch (P<0.05). The mRNA expressions of RUNX2 and DLX5 in group C were significantly higher than those in groups A, B, D, and E at 24 hours after mechanical stretch (P<0.05). Western blot detection showed that higher protein expression of TNC in group B than group E at each time point after mechanical stretch (P<0.05), and the protein expression of CEBPα was significantly inhibited when compared with group E at 24 hours after mechanical stretch (P<0.05). At 24 hours after mechanical stretch, the protein expression of RUNX2 in group C was significantly higher than that in group E (P<0.05); and the protein expression of TNC was significantly lower than that in group E at 24 and 48 hours after mechanical stretch (P<0.05). At 48 hours after mechanical stretch, the protein expression of CEBPα was significantly increased and the protein expression of TNC was significantly decreased in group D when compared with group E (P<0.05), but no significant difference was found in the protein expression of RUNX2 between groups D and E (P>0.05). Conclusion The mechanical strain could promote differentiation of TSCs, and different parameter of stretch will lead to different differentiation. The best stretch condition for tenogenic differentiation is 4% strength and 2 Hz frequency for 24 hours; the best stretch condition for osteogenic differentiation is 8% strength and 1 Hz frequency for 24 hours; and the best stretch condition for adipogenic differentiation is 8% strength and 2 Hz frequency for 48 hours.
Objective To investigate whether mechanical stretch stimulation affects the expression of the immediate early gene c-fos mRNA in rat Achilles-derived tendon stem cells (TSCs)in vitro. Methods TSCs were isolated from the Achilles tendons of 8 weeks old male Sprague Dawley rats by enzymatic digestion method and cultured for 3 passages. The TSCs were stimulated by a uniaxial cyclic stretching loading system under the condition of 1 Hz, respectively with 4% or 8% stretch intensity for 0, 5, 15, 30, 60, and 120 minutes. At each time point, TSCs were collected to detect c-fos mRNA expressions and to find the best time-point Tmax by real-time fluorescence quantitative PCR. Then, TSCs were simulated with 2%, 4%, 6%, 8%, or 12% stretch intensity for Tmax to observe the relative expressions of c-fos mRNA under different stretch intensities. Next, TSCs were stretched for 0, 5, or 15 minutes respectively and followed by incubation at relax status up to Tmax to observe the changes of c-fos mRNA expressions after short period stimulation. Finally, TSCs were stimulated with 4% or 8% stretch intensity respectively for 0, Tmax, or 120 minutes to detect the expressions of the tenogenic differentiation related genes [collagen type I, tenomodulin (TNMD)], the osteogenic differentiation related genes [runt related transcription factor 2 (Runx2), distal-less homeobox 5 (Dlx5)], and the adipogenic differentiation related gene [fatty acid binding protein 4 (FABP4)]. Results Under 4% or 8% stretch intensity, the relative expressions of c-fos mRNA significantly increased at 15 minutes (P<0.05), reached the maximum at 30 minutes (P<0.05), and returned to baseline at 60 minutes (P>0.05) when compared with expression at 0 minute. Therefore, Tmax was 30 minutes. The stretch intensity of 2% was enough to cause the expression of c-fos mRNA at 30 minutes, and the expression was significantly higher under the stretch intensity of 6%, 8%, and 12% than 2% and 4% (P<0.05). Even for a short period stimulation of 5 minutes, c-fos mRNA expression could still significantly increase at 30 minutes (P<0.05). The relative expressions of differentiation related genes at 30 and 120 minutes showed no significant difference when compared with the expression at 0 minute under 4% stretch intensity (P>0.05); but the relative expression of Runx2 gene significantly increased at 30 minutes, and the relative expressions of collagen type I, TNMD, Dlx5, and Runx2 increased at 120 minutes under 8% stretch intensity (P<0.05). Conclusion Mechanical stretch stimulation can affect the relative expression of the immediate early gene c-fos mRNA of rat Achilles-derived tendon stem cellsin vitro, and there is time- and intensity-dependence. It is suggested that the mechanical stimulation with different time or intensity may affect the differentiation of TSCs at early stage. This study is meaningful for the further study on TSCs intracellular mechanical signal transfer mechanism.
Objective To study the effect of mechanical stretch on the microenvironment of BEAS-2B on macrophage polarization and the role of polarized macrophages in the epithelial-mesenchymal transition (EMT) of BEAS-2B. Methods Using enzyme linked immunosorbent assay to detect the changes in the levels of cytokines such as interferon-γ, granulocyte-macrophage colony stimulating factor, tumor necrosis factor-α, interleukin (IL)-4, IL-6, IL-10 in the supernatant of lung epithelial cells cultured statically and mechanically stretched. The M0 macrophages (derived from THP-1) were stimulated by stretch/static conditioned medium of BEAS-2B. The surface markers of M1 (CD197) /M2 (CD206) macrophages were detected by flow cytometer. Stretch/static conditioned medium were used to stimulate the co-culture system of macrophages and BEAS-2B in the presence or absence of platelet-derived growth factor receptor inhibitor (PDGFRi), then the protein expression level of EMT makers was examined by Western blot. Results Exposure of BEAS-2B to mechanical stretch resulted in significantly higher production of the pro-M1/M2 polarized factor. The EMT of the co-culture system of M0 and BEAS-2B could be induced by stretch conditioned medium, epithelial marker cytokeratin (CK)-8 and E-cadherin were decreased, while mesenchymal marker α-smooth muscle actin, N-cadherin and vimentin were increased in stretch conditioned medium group. The expression of platelet-derived growth factor (PDGF) was significantly higher in stretch conditioned medium group. The PDGFRi can block the EMT in stretch conditioned medium group. Conclusions The lung epithelial cell supernatant induced by mechanical stretch can promote the polarization of macrophages to M1 and M2. Polarized macrophages promote EMT in human lung epithelial cells via PDGF, and blocking PDGF might attenuate the VILI-associated lung fibrosis.
ObjectiveTo investigate the effectiveness of channel screw combined with skin-stretching technique in treatment of pelvic fracture with severe Morel-Lavallée lesion.MethodsBetween January 2017 and May 2020, 11 patients with pelvic fractures complicated with severe Morel-Lavallée lesions were treated with channel screw combined with skin-stretching technique. There were 8 males and 3 females, with an average age of 39.2 years (range, 28-58 years). Causes of injury included traffic accident in 9 cases and falling from hight in 2 cases. The time from injury to hospital admission ranged from 1 to 6 days (mean, 3.7 days). According to the Tile classification, the pelvic fractures were rated as type C1 in 7 cases, type C2 in 3 cases, and type C3 in 1 case. The sites of Morel-Lavallée lesions were buttocks in 8 cases, hips in 2 cases, and thigh in 1 case. There was 1 case of rectal injury, 1 case of splenic rupture, 3 cases of craniocerebral injury, 2 cases of chest injury, 4 cases of spinal fracture, and 6 cases of sacral nerve injury. X-ray films were performed to observe reduction and healing of fracture. The quality of fracture reduction was evaluated by Matta standard at 1 week after operation. Wound healing and complications were observed. Majeed scoring was used to evaluate hip function and Gibbons sacral nerve injury grading was used to evaluate neurological function recovery.ResultsThe patients underwent 4-7 operations, with an average of 5.8 operations. The time of first operation (pelvic fracture fixation, debridement, and skin distractor installation) was 115-275 minutes, with an average of 186.5 minutes. The amount of intraoperative blood loss was 30-80 mL, with an average of 45.5 mL. All patients were followed up 6-12 months, with an average of 8.3 months. The quality of fracture reduction according to the Matta standard was excellent in 7 cases, good in 2 cases, and fair in 2 cases, with an excellent and good rate of 81.8%. All fractures healed at 3-6 months after operation, with an average of 4.5 months. At last follow-up, the hip functions were excellent in 7 cases and good in 4 cases according to Majeed scoring, with an excellent and good rate of 100%. Among the 6 patients complicated with sacral nerve injury, the Gibbons sacral nerve injury grading reached gradeⅠ for 4 cases, gradeⅡ for 1 case, and grade Ⅲ for 1 case. The wounds of 9 cases were sutured directly after skin-stretching treatment for 25-32 days, with an average of 28 days. The dermal edge necrosis occurred in 1 case, and the defect was repaired by free skin grafting. The skin superficial dry necrosis of the wound occurred in 1 case, and healed by dressing change.ConclusionIn the treatment of pelvic fracture complicated with severe Morel-Lavallée lesion, the channel screw and skin-stretching technique showed their own advantages, which can obtain early fracture fixation and good wound healing.
Objective To observe the effectiveness of disposable skin stretch closure in the treatment of wounds with skin and soft tissue defects that were difficult to close. Methods The clinical data of 13 patients with skin and soft tissue defects that were difficult to close treated with disposable skin stretch closure and met the selection criteria between July 2021 and February 2022 were retrospectively reviewed. There were 9 males and 4 females, the age ranged from 15 to 71 years with a mean of 39.8 years. The causes of injury included falling injury in 5 patients, traffic accident injury in 5 patients, and falling from height injury in 3 patients. The causes of skin soft tissue defects included open fractures in 4 patients, wound infection in 4 patients, osteomyelitis in 3 patients, degloving injury in 1 patient, and necrosis of skin graft in 1 patient. The injury was located at calf in 8 patients, calcaneus in 3 patients, pelvis in 1 patient, and plantar in 1 patient. The skin and soft tissue defects ranged from 5.0 cm×2.0 cm to 10.5 cm×6.5 cm. Wound conditions (wound closure and wound healing) and the presence or absence of complications were recorded. Results All 13 patients were followed up 32-225 days with a median of 164 days. The wound closure time ranged from 5 to 14 days, with a mean of 8.8 days. The wound closure speed ranged from 0.7 to 13.7 cm2/day, with a mean of 3.6 cm2/day. All wounds healed at grade A, and no complication such as skin edge injury, wound necrosis, infection, dehiscence, and edema occurred. No patient complained of pain or discomfort, and no obvious scarring was found during follow-up. The wound healing time ranged from 17 to 28 days, with a mean of 21.7 days. One of them was transferred to other department due to lung cancer condition changes after using disposable skin stretch closure, and the wound had directly healed without suturing at 17 days after operation. Conclusion The effectiveness of disposable skin stretch closure in the treatment of wounds with skin and soft tissue defects that were difficult to close was exact, with short wound closure time, few complications, and easy operation.
ObjectiveTo discuss the efficacy of skin stretcher applied for repair of postoperative skin and soft tissue defects in tibial fractures.MethodsBetween April 2016 and March 2017, 15 cases with skin and soft tissue defects after tibial fractures fixation were treated with the skin stretcher. There were 11 males and 4 females with an age of 24-59 years (mean, 37.5 years). The causes of injury included traffic accident in 7 cases, bruise in 3 cases, falling from height in 3 cases, and falling in 2 cases; without nerve and vascular injury in all patients. These cases were followed up 1-3 months after their first surgery, consisting of 3 closed fractures treated with open reduction and plate and screw fixation, 12 open fractures treated with external fixation after debridement. The area of skin defects ranged from 14 cm×5 cm to 20 cm×7 cm, all of which were stripped or spindle shaped skin defects. First, the skin was penetrated by two Kirschner wires which were locked by skin stretchers on both sides of the skin defect longitudinally. Then, the tension of skin stretchers was timely adjusted according to the skin flap blood supply and muscle compression. Finally, Kirschner wires and skin stretchers were removed when the edge of skin contacted and been sutured.ResultsAll skin and soft tissue defects were covered after stretching for 6-13 days. The interrupted sutured wounds healed at 12 days. Clinical scores of wound healing decreased from 3.40±0.51 at immediate postoperatively to 1.27±0.46 at 12 days postoperatively, showing significant difference (t=12.911, P=0.000). All the patients were followed up 4-12 months (mean, 6.5 months). After stretching, the skin color, elasticity, and pain and touch feeling were similar with the normal skin, and the hair growth was normal. After operation, 1 case of nail tract infection and 2 cases of calf discomfort occurred, and all were relieved after treatment.ConclusionIt is an effective method for repairing postoperative skin and soft tissue defects in tibial fractures with the application of skin stretchers.