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Objective:To evaluate the various wire tension belt ventral compression wiring technologiesfor treating several types of femoral greater trochanter fractures in total hip replacement, according to the different types of greater trochanter of femur fractures.Methods:From March 2013 to June 2019, a total of 1 280 cases of primary total hip arthroplasty were completed in our hospital, 21 patients with greater trochanter fractures were identified in total hip replacement. There were 11 males and 10 females with an average age of 65.81±6.45 years (range 42-76 years). All of them were unilateral. There were 11 cases on the left and 10 cases on the right. There were 11 cases of osteoarthritis secondary to hip dysplasia, 4 cases of hip osteoarthritis, 4 cases of aseptic necrosis of femoral head and 2 cases of femoral neck fracture. Different wire tension belt ventral compression wiring technologies were used for each fracture type. Harris hip function score, Parker activity score, and visual analogue scale (VAS) score of hip pain were evaluated during follow-up. X-ray films were taken to evaluate the fracture healing, prosthesis position, loosening and dislocation.Results:Three new fracture types were proposed: A transverse fracture from the greater trochanter tip to the base (4 cases); B oblique fracture from the greater trochanter tip to the base (according to the fracture line direction, type B was further divided into types B1 (4 cases) and B2 (6 cases); and C fracture line from the greater trochanter to subtrochanteric plane (7 cases). Among the 21 patients, one died at an early stage, two were lost during follow-up, and 18 were followed up for an average of 30.7±7.6 months. In 18 patients, the mean operation time was 110.0±20.0 min, and the mean intraoperative blood loss was 356.9±115.7 ml. The patients' Harris score was 35.26±5.52 at the preoperative, 65.7±6.42 at the 3 months after operation, and 87.75±6.21 at the final follow-up. The difference was statistically significant ( F=377.23, P<0.001). The patients' Parker score was 2.17±0.98 at the preoperative, 5.94±1.11 at the 3 months after operation,and 8.01±0.77 at the final follow-up. The difference was statistically significant ( F=170.96, P<0.001). The patients' VAS score was 6.22±1.11 at the preoperative, 2.61±0.92 at the 3 months after operation, and 1.28±0.67 at the final follow-up. The difference was statistically significant ( F=139.71, P<0.001). Deep vein embolism, heterotopic ossification was noted in one and another patient, respectively. The patient with non-union refused reoperation and had a broken steel wire, lower-limb limp, and no notable pain at the 12-month follow-up examination. Radiographs of 17 patients showed good location of the femoral prosthesis and no chronic pain. Conclusion:Different types of greater trochanter fractures in total hip arthroplasty were proposed, using different wire tension belt ventral compression wiring technologies for the various types of femoral greater trochanter fractures during total hip replacement can improve clinical outcomes.
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Objective:To investigate the effectiveness and safety of middle-column preserved pedicle subtraction closing-opening wedge osteotomy for the treatment of stiff kyphosis.Methods:From January 2016 to April 2018, 12 patients with stiff kyphosis in our department were treated with middle-column preserved pedicle subtraction closing-opening wedge osteotomy. The patients' operative time, intraoperative blood loss, postoperative drainage, surgical complications, low back pain and leg pain visual analogue scale (VAS), Oswestry dysfunction index (ODI) score, and SF-36 were recorded.These parameters were compared at preoperative, postoperative, and at the final follow-up. Coronal parameters included lumbar scoliosis Cobb angle, C 7 vertebral body center to humeral vertical line distance (C 7PL-CSVL), whilesagittal parameters includedlumbar Lordosis (LL), sacral slope (SS), pelvic tilt (PT), and sagittalvertical axis (SVA). Results:All of 12 patients successfully completed the operation.The mean operation time was 238.20±65.95 min, the mean intraoperative blood loss was 440.50±133.60 ml.The patients’ODI score was 65.92%±6.96% at the preoperative, and 21.00%±3.19% at the final follow-up. The difference was statistically significant ( t=20.32, P<0.0001).The VAS score of back pain was 6.00±0.95 at preoperative, 2.33±0.89 at 3 months postoperatively, and 1.42±0.51 at the final follow-up. The VAS score of leg pain was 6.91±1.24 at preoperative, 2.50±1.00 at 3 months postoperatively, and1.50±0.52 at the final follow-up. There was significant difference in SF-36 at preoperative and at final follow-up ( P<0.05). The differences in LL, SS, PT and SVA at the preoperative and at final follow-up were statistically significant ( F=17.47, P<0.001; F=5.015, P=0.0125; F=14.66, P<0.001; F=81.11, P<0.001) . There was significant difference in lumbar scoliosis Cobb angle and C 7PL-CSVL at the preoperative and at final follow-up ( F=87.19, P<0.001; F=100.9, P<0.001) . Conclusion:The advantages of this surgical procedure includesimple operation, reducedsurgery time, and shorten intraoperative bleeding, which can effectively relief clinical symptoms, improve the quality of life, correctkyphosis, and maintain the patient's spinal-pelvic balance.
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Objective:To investigate the effect of middle-column preserved pedicle subtraction closing-opening wedge osteotomy for the treatment of old thoracolumbar compression fractures combined with kyphosis deformity.Methods:A retrospective case series study was performed to analyze data of 27 patients with old thoracolumbar compression fractures combined with kyphosis deformity admitted in Taizhou Hospital from January 2010 to January 2017. There were 10 males and 17 females, with age range of 45-75 years (mean, 61.7 years). The injured segments and osteotomy segments included T 11 in 5 patients, T 12 in 10, L 1in 8 and L 2 in 4. Time from initial fracture to surgery was 9-120 months (mean, 23.2 months). According to the American Spinal Injury Association (ASIA) classification, neurological impairment symptoms were detected in 9 patients, including grade C in 1 and grade D in 8. All patients underwent one-level middle-column preserved pedicle subtraction osteotomy. Operation time, blood loss, and perioperative complications were recorded. Before operation, at 3 months after operation and at latest follow-up, kyphosis Cobb angle, sagittal vertical axis (SVA) and height of anterior column (AC) as well as posterior column (PC) were measured. Visual analogue scale (VAS) and Oswestry disability index (ODI) score were used to evaluate the clinical efficacy. American Spinal Injury Association (ASIA) score was used to assess neurological function. Results:All patients were followed up for average 18.1 months (range, 12-34 months). Operation time was (155.2±35.4)minutes (range, 130-250 minutes). Blood loss was (338.1±101.4)ml (range, 150-550 ml). No serious neurological or vascular complications occurred during perioperative period. Kyphosis Cobb angle was (6.0±3.1)° at postoperative 3 months compared to preoperative (46.5±8.5)°( P<0.05), and showed no significant loss at latest follow-up [(7.9±3.8)°] ( P>0.05). SVA was improved significantly from preoperative [42.7(25.5, 78.2)]mm to [5.5(1.2, 7.3)]mm at postoperative 3 months ( P<0.05). AC height was increased by average 16.3 mm at postoperative 3 months compared to the preoperative level ( P<0.05), with no significant change in PC height ( P>0.05). There was no significant difference in SVA, AC height and PC height at postoperative 3 months and latest follow-up ( P>0.05). There were significant differences in VAS [(1.7±0.8)points, (2.3±1.4)points] and ODI (17.3±7.5, 19.4±4.3) at postoperative 3 months and at latest follow-up compared to these before operation [(7.7±1.3)points, 61.4±6.2] ( P<0.05), with no significant differences in VAS and ODI at postoperative 3 months and latest follow-up ( P>0.05). No implant failure was noted during follow-up. The osteotomy surface was fused in all patients at postoperative 6 months. At latest follow-up, ASIA grade was improved from grade C to grade D in 1 patient and from grade D to grade E in 8 patients. Conclusion:Middle-column preserved pedicle subtraction closing-opening wedge osteotomy can effectively correct old thoracolumbar fractures with kyphosis, relieve pain and improve nerve function.
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Objective@#To explore the clinical effect of reduction and reconstruction of the removed bony structure after one-stage posterior resection of high cervical tumors.@*Methods@#From October 2009 to March 2018, 17 patients including 10 males and 7 females of high cervical tumors who underwent one-stage posterior resection with an average age of 57 years (26~84 years) were reviewed. There were 11 shwannomas, 3 meningiomas and 3 concurrent shwannoma and meningioma arising in the same level, respectively. Reduction with (14 cases) or without internal fixation (3 cases) were performed for the removed C1 posterior arch or C2 laminar and spinous process. The clinical effects were compared with Visual analogue score (VAS), Japanese Orthopaedic Association scores (JOA) and American Spinal Injury Association (ASIA) grade. The cervical lordosis and range of motion were measured with the X-ray before the operation and at the last follow-up.@*Results@#There were no vertebral artery injury or massive hemorrhage during the surgeries. The operation time was 184±43 min, blood loss was 203±223 ml, and mean follow-up period was 29.1±28.2 months. No recurrence was found during the follow-up, and the motor and sensory were significant recovered in all patients after surgery. VAS score and JOA score were significantly improved at the last follow-up. ASIA grade was C for 1 case, D for 11 cases and E for 5 cases before surgery. After surgeries, C improved to D, 8 cases of D improved to E and 3 cases of D failed improved to E. Although the cervical lordosis and range of motion was decreased significantly in the last follow-up in X-ray, no patients complained stiffness and discomfort in rotation or flexion and extension of the neck. Cardiac arrest during operation was occurred in 1 case, and heartbeat recovered after stopping the manipulation. CSF leakage was found in 9 cases and no surgical site infection was occurred.@*Conclusion@#Resection of high cervical dumbbell-shape tumors is a demanding surgery with high incidence of complications. The reduction and reconstruction of removed bony structure without fusion could rebuild the stability of high cervical spine and preserve the cervical range of motion as much as possible which improves clinical effect.
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Objective To explore the clinical effect of reduction and reconstruction of the removed bony structure after one?stage posterior resection of high cervical tumors. Methods From October 2009 to March 2018,17 patients including 10 males and 7 females of high cervical tumors who underwent one?stage posterior resection with an average age of 57 years (26~84 years) were reviewed. There were 11 shwannomas, 3 meningiomas and 3 concurrent shwannoma and meningioma arising in the same level, respectively. Reduction with (14 cases) or without internal fixation (3 cases) were performed for the removed C1 posteri?or arch or C2 laminar and spinous process. The clinical effects were compared with Visual analogue score (VAS), Japanese Ortho?paedic Association scores (JOA) and American Spinal Injury Association (ASIA) grade. The cervical lordosis and range of motion were measured with the X?ray before the operation and at the last follow?up. Results There were no vertebral artery injury or massive hemorrhage during the surgeries. The operation time was 184±43 min, blood loss was 203±223 ml, and mean follow?up pe?riod was 29.1±28.2 months. No recurrence was found during the follow?up, and the motor and sensory were significant recovered in all patients after surgery. VAS score and JOA score were significantly improved at the last follow?up. ASIA grade was C for 1 case, D for 11 cases and E for 5 cases before surgery. After surgeries, C improved to D, 8 cases of D improved to E and 3 cases of D failed improved to E. Although the cervical lordosis and range of motion was decreased significantly in the last follow?up in X?ray, no patients complained stiffness and discomfort in rotation or flexion and extension of the neck. Cardiac arrest during operation was occurred in 1 case, and heartbeat recovered after stopping the manipulation. CSF leakage was found in 9 cases and no surgical site infection was occurred. Conclusion Resection of high cervical dumbbell?shape tumors is a demanding surgery with high in?cidence of complications. The reduction and reconstruction of removed bony structure without fusion could rebuild the stability of high cervical spine and preserve the cervical range of motion as much as possible which improves clinical effect.
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OBJECTIVE: To investigate the expression of Toll-like receptor 4 (TLR4)/myeloid differentiation factor (MyD88)/nuclear factor-κB (NF-κB) pathway genes and related inflammatory factors tumor necrosis factor-α (TNF-α), interleukin (IL)-12, IL-6 in patients with secondary spinal cord injury (SSCI) and the correlations with prognosis. METHODS: The clinical data of 105 SSCI patients and 40 healthy subjects were reviewed. According to Frankel's classification of spinal cord injury, the patients were divided into complete injury group and incomplete injury group, and according to the improvement of Japanese Orthopedic Association (JOA) scores, the patients were divided into good prognosis group and poor prognosis group. The expression of TLR4, MyD88, NF-κB in peripheral blood mononuclear cells (PBMC) and serum TNF-α, IL-12, IL-6 levels were compared between SSCI patients and healthy controls, between patients with complete and incomplete injury, between patients with poor and good prognosis. Logistic regression analysis was used to analyze the risk factors leading to poor prognosis of SSCI, and Pearson's correlation analysis was used to analyze the correlation between JOA score and the above indicators. RESULTS The expressions of TLR4, MyD88, NF-κB in PBMC and serum TNF-α, IL-12, IL-6 levels in SSCI patients were significantly higher than those in healthy subjects (all P<0.01), those in complete injury group were higher than those in incomplete injury group, and those in poor prognosis group were higher than those in good prognosis group (all P<0.01). The proportions of patients with Frankel grade A, spinal cord edema or hemorrhage, spinal cord injury length longer than 4 cm in poor prognosis group was significantly higher than those in good prognosis group (all P<0.01). Logistic regression analysis showed that Frankel grade, spinal cord edema or hemorrhage, length of spinal cord injury, relative expressions of TLR4, MyD88, NF-κB in PBMC, serum levels of TNF-α, IL-12 and IL-6 were risk factors for poor prognosis in SSCI patients (P<0.05 or P<0.01). Pearson's correlation analysis showed that JOA improvement rate was negatively correlated with the relative expressions of TLR4, MyD88, NF-κB mRNA in PBMC and serum TNF-α, IL-12, IL-6 levels (P<0.05 or P<0.01). CONCLUSIONS The activation of TLR4/MyD88/NF-κB pathway and the up-regulation of the expression of related inflammatory factors TNF-α, IL-12 and IL-6 are involved in the progression of SSCI, which are closely related to the neuroinflammatory injury, and can be used as reference indexes for evaluating prognosis in SSCI patients.
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Objective To investigate the effectiveness and safety of middle-column preserved pedicle subtraction closingopening wedge osteotomy for the treatment of ankylosing spondylitis (AS)-related thoracolumbar kyphosis.Methods From January 2010 to December 2016,eleven patients (9 males and 2 females) who underwent one-level middle-column preserved pedicle subtraction osteotomy with an average age of 40.8 years (21-68 years) were reviewed.The average thoracolumbar kyphosis angle (TLK) was 50.5°±9.6° and the average lumbar lordosis angle was-2.5°±24.1°.The thoracolumbar kyphosis,sagittal vertical axis (SVA),lumbar lordosis,pelvic tilt,sacral slope,thoracic kyphosis,Scoliosis Research Society (SIRS) 22,Oswestry disability index (ODI) score,the length of anterior column and posterior column at the pre-and post-operation,operation time,perioperative blood loss and complications were recorded.Results The osteotomy sites of 11 cases included 7 in L2,2 in L3 and 2 in T12.Theaverage operation time was 156.8 min (120-220 min).The average blood loss was 604.5 ml (350-900 ml).The average time of followup was 24 months (12-42 months).Complications were encountered in 2 patients.There were 1 casewith transient neurological deficits,another case with incision infection.No serious neurological or vascular complications occurred in all cases.The thoracolumbar kyphosis (TLK),lumbar lordosis,pelvic tilt,sacral slope,thoracic kyphosis,SRS 22 and ODI score were improved significantly.The preoperative TLK cobb was 50.5° (36°-66°),which improved to 5.1 ° (1 °-11°) at the final follow-up with a mean correction rate of 89.9％.Sagittal migrationwas improved from 184.6 mm preoperatively to 79.2 mm atthe final follow-up with an average correctionrate of 49.3％.The differences of the length of posterior column of osteotomy site after operation showed no statistical significance.All patients had solid fusion at osteotomy site and no instrumentational failure and loosening were found over the follow up.Conclusion Middle-column preserved pedicle subtraction closing-openingwedge osteotomy is safe and effective for correction of the thoracolumbar kyphosis deformity occurring in ankylosing spondylitis,resulting in satisfactory out comes with acceptable complications.
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Objective To evaluate the feasibility and efficacy of posterior enlargement of spinal canal for the treatment of multi-segmental cervical diseases without cervical lordosis.Methods From January 2013 to June 2017,a retrospective study was conducted with 21 patients of multi-segmental cervical diseases accompanied cervical lordosis loss,and the complete followup data was obtained.There were 14 males and 7 females,with an average age of 53.9±7.3 years (range,42-65 years).There were 14 multi-segmental cervical spondylotic myelopathy,5 ossification of posterior longitudinal ligament,and 2 congenital cervical stenosis included in this study.The cervical lordotic angle and cervical curvature index were measured preoperatively and 1 year postoperatively.To access the enlargement of spinal canal and spinal cord,the anteroposterior diameter and cross section area of spinal canal or spinal cord were measured on MRI preoperatively and 1 year postoperatively.The Japanese Orthopaedic Association Scores (JOA) was applied to evaluate the neurological function at preoperation and postoperation.Visual Analogue Scales (VAS) was applied to evaluate the pain degree at preoperation and postoperation.Frankel classification was used to assess the severity of spinal cord injury at preoperation and postoperation.Results The follow-up time was 12-26 months,with an average of 16.4 months.The cervical lordosis angle was 3.1°±2.3° preoperatively,and 4.2°±1.6° 1 year postoperatively with a significant difference.The cervical curvature index was 4.4％ ± 1.7 ％ preoperatively and 5.0％ ± 1.5 ％ 1 year postoperatively with no statistically difference.Except for C7T1 level,the preoperative anteroposterior diameter and cross section area of spinal canal at C2.3,C3.4,C4.5,C5.6,and C6.7 level were lower than that at 1 year after operation with a significant difference.Except for C2,3 and C7T1 and level,the preoperative anteroposterior diameter and cross section area of spinal cord at C3,4,C4,5,C5,6,and C6,7 level were significantly lower than that at 1 year after operation.The average JOA score preoperatively was 8.9±1.7.The average JOA score at 3 months postoperatively was 13.1±2.0,which was significantly higher than that preoperatively.At 3 months postoperatively,the average improvement rate was 52.0％,and the superior rate was 52.3 ％.At 1 year postoperatively,the average JOA score was 13.3±2.1,which improved significantly from that preoperatively.The average improvement rate was 54.3 ％,and the superior rate was 61.9％.The VAS score at preoperatively was 3.0±2.4,and which was 2.7± 1.7 at 1 year postoperatively with no significant differences.At pre-operation,the level of Frankel classification was C level in one (4.8％) case,D level in 8 (38.1％) cases and E level in 12 (57.1％) cases.At 1 year postoperatively,the level of Frankel classification was C level in one (4.8％) case,D level in 6 (28.6％) cases and E level in 14 (66.7％) cases,compared with that at preoperatively,there was no statistically significant difference.One patients suffered from neurologic deterioration at 1 year after surgery and recovered after anterior cervical surgery.No other serious complications were occurred.Conclusion For the patients with multi-segmental cervical diseases accompanied cervical lordosis loss,effective spinal decompression by cervical posterior laminoplasty was feasible,and a good clinical efficacy was achieved.
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Objective To investigate the treatment of the complications of puncture lapsus after the percutaneous vertebroplasty (PVP) for osteoporotic fractures.Methods From December 2011 to November 2014,3 female patients with postoperative complications of PVP which were treated for osteoporotic fractures,aged from 71 to 82 years (average,78 years old) were involved.Each of them performed a revision surgery in our hospital.One of them was performed with PVP of the 12th thoracic vertebral due to the osteoporotic thoracic vertebral compression fracture.However,bone cement was leaked into spinal canal after PVP,and the patient suffered from left abdominal constriction and impaired of sensation in left inguinal region.She underwent anterior approach of decompression,cement removal and internal fixation one year after the first operation.The second case was performed with PVP of the 1st lumbar vertebral due to the osteoporotic lumbar vertebral compression fracture.In this case,bone cement was leaked into spinal canal after PVP,and the patient suffered from abdominal and lower extremity pain,paralysis,and hypoesthesia of lower limbs.This patient was treated with posterior approach of decompression,cement removal and internal fixation.The third case was performed with the 12th thoracic vertebral PVP due to the osteoporotic thoracic vertebral compression fracture.Subdural hemorrhage happened after PVP,and the patient suffered from paralysis and sensory loss of the two lower limbs.This patient was treated with posterior approach of laminotomy,hemostasis in the spinal canal and evacuation of hematoma.We performed a follow up from 21 to 29 months (average,24.7 months),to observe the recovery of the patients.Results one case' s abdominal constriction eliminated and the inguinal region pain improved after the revision surgery,and there's no internal fixation loosening with the follow-up of 21 months.The other case's abdominal and lower limb pain relieved,the lower limb muscle strength recovered to grade 4,and the tactile of lower limb recovered to normal after the revision surgery.There' s no internal fixation loosening with the follow-up of 29 months.One case of patients with slightly recovered of lower extremity muscle strength and feeling after surgery,and remained lower limb pain,died two years after the surgery.Conclusion Complications of spinal cord compression after percutaneous vertebroplasty (PVP) for osteoporotic fractures can get good outcomes by using appropriate revision surgeries,although revision surgery is difficult and risky.
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Objective To investigate characteristics of cage migration after transforaminal lumbar interbody fusion (TLIF) and related risk factors.Methods A retrospective study was conducted to review cage migration in 512 patients who had undergone TLIF procedure from January 2010 to June 2011 in 5 spinal research centers.There were 255 males and 257 females,aged from 37 to 77 years (average,54.7 years).All patients were followed up at 3,6,12 months after operation.The clinical outcomes were evaluated using the visual analogue scores (VAS) and Oswestry disability index (ODI).X-rays and 3D CT scans were used to analyze the incidence and related risks factors of cage migration in these patients.Results Cage migration was found in 6 of 512 patients,the total incidence was 1.17％.Significant difference was found between each center.Cages with different shapes had different incidence.The analysis showed that the incidence of migration of rectangular-shaped cage (3.11％,5/161) was significantly higher than that of kidney-shaped cage (0.28％,1/351).The cage in double-segment TLIF (5.75％,5/87) was easier to migrate than that in monosegment TLIF (0.24％,1/425); furthermore,linear type endplate(3.50％,5/143) was remarkably easier to migrate than concave-concave one (0.27％,1/369).Conclusion Difference in operative skills,cage shape,number of fused segments,adjacent endplate shape,and lumbar spondylolisthesis might be risk factors for cage migration after TLIF.
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Objective To investigate the clinical outcomes of sternoclavicular hook plate in treatment of the anterior sternoclavicular joint dislocation. Methods A new device named sternoclavicular hook plate was devised by our team. Between May 2002 and Octorber 2009, 66 patients with sternoclavicular joint anterior dislocation were treated with the new device, among whom there were 47 males and 19 females,aged 21-68 years old (average, 32.6 years old). Twenty-one cases were caused by crush injury, 5 cases by falling and 40 cases by traffic accident. Anterior fracture-dislocation was found in 41 cases. According to the Allman system, there were 35 cases of type Ⅱ and 31 cases of type Ⅲ. Patients were evaluated with serial clinical and radiographic examinations. Rockwood score were used after the operation to assess the curative effect. Results The average operative time was 33 min (range, 20-48 min). The mean blood loss was 60 ml (range, 20-90 ml). There were no vascular or peripheral nerve injuries in the patients. All incisions healed smoothly. The X-ray and CT showed that the reduction of sternoclavicular joint and the location of internal fixation were satisfactory. All the 66 patients were followed up for 12-37 months (average, 17 months). There was no internal fixation failure, redislocation or other complications. The sternoclavicular hook plate was removed 12 months after operation. The mean Rockwood's score was 13.2 (8 to 15). There were excellent in 50cases, good in 15 cases, and fair in 1 case. Conclusion The sternoclavicular hook plate is a new, safe and liable technique for sternoclavicular fracture-dislocation. This new technique is helpful for early functional exercises.
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Objective To study the effects of cryopreservation on the immunogenicity of human umbilical vein endothelial cells(HUVEC).Methods HUVEC were isolated ex vivo and cryopreserved.Lymphocyte stimulation index(SI)was analyzed by MTT in lymphoeyte-endothelial cell co-culture.Both HLA-ABC and HLA-DR antigen expression on fresh or cryopreserved HUVEC,and the effects of IFN-γ treatment on HLA antigen expression in both groups were determined by using flow cytometry.Results No difference in SI was observed between fresh prepared and cryopreserved HUVEC(1.716±0.181 vs 1.686±0.145,P>0.05).The percentage of HLA-ABC expression was(96.6±1.9)%and(96.0±1.4)%in fresh and cryopreserved HUVEC(P>0.05),and the mean intensity for HLA-ABC expression was 84.1±5.7 and 82.4±4.8 in fresh and cryopreserved HUVEC(P>0.05),respectively.However,no HLA-DR expression was observed in both groups.When treated with IFN-γ,HLA-ABC expression was significantly up-regulated,and HLA-DR expression was induced in a dose-dependent manner.No significant difference was found in the HLA-ABC expression between fresh and cryopreserved HUVEC(P>0.05),while the HLA-DR expression in cryopreserved HUVEC was remarkably lower than in fresh HUVEC with the increase of IFN-γ(P<0.01).Conclusion The immunogenicity of HUVEC remains stable by cryopreservation without IFN-γtreatment or treated with low concentration of IFN-γ(≤50 U/ml).However,the HLA-DR expression in HUVEC was remarkably reduced in eryopreserved cells treated with a high concentration of IFN-γ(≥100 U/ml).These data indieated that the effects of cryopreservation on immunogenicity of HUVEC may result from the decreased responses of HLA-DR expression by the stimulation of IFN-γ treatment.