Due to matching biomechanical properties and significant biological activity,Mg-based implants present great potential in orthopedic applications.In recent years,the biocompatibility and therapeutic effect of magnesiu...Due to matching biomechanical properties and significant biological activity,Mg-based implants present great potential in orthopedic applications.In recent years,the biocompatibility and therapeutic effect of magnesiumbased implants have been widely investigated in trauma repair.In contrast,the R&D work of Mg-based implants in spinal fusion is still limited.This review firstly introduced the general background for Mg-based implants.Secondly,the mechanical properties and degradation behaviors of Mg and its traditional and novel alloys were reviewed.Then,different surface modification techniques of Mg-based implants were described.Thirdly,this review comprehensively summarized the biological pathways of Mg degradation to promote bone formation in neuro-musculoskeletal circuit,angiogenesis with H-type vessel formation,osteogenesis with osteoblasts activation and chondrocyte ossification as an integrated system.Fourthly,this review followed the translation process of Mg-based implants via updating the preclinical studies in fracture fixation,sports trauma repair and reconstruction,and bone distraction for large bone defect.Furthermore,the pilot clinical studies were involved to demonstrate the reliable clinical safety and satisfactory bioactive effects of Mg-based implants in bone formation.Finally,this review introduced the background of spine fusion surgeryand the challenges of biological matching cage development.At last,this review prospected the translation potential of a hybrid Mg-PEEK spine fusion cage design.展开更多
Laser powder bed fusion(L-PBF)of Mg alloys has provided tremendous opportunities for customized production of aeronautical and medical parts.Layer thickness(LT)is of great significance to the L-PBF process but has not...Laser powder bed fusion(L-PBF)of Mg alloys has provided tremendous opportunities for customized production of aeronautical and medical parts.Layer thickness(LT)is of great significance to the L-PBF process but has not been studied for Mg alloys.In this study,WE43 Mg alloy bulk cubes,porous scaffolds,and thin walls with layer thicknesses of 10,20,30,and 40μm were fabricated.The required laser energy input increased with increasing layer thickness and was different for the bulk cubes and porous scaffolds.Porosity tended to occur at the connection joints in porous scaffolds for LT40 and could be eliminated by reducing the laser energy input.For thin wall parts,a large overhang angle or a small wall thickness resulted in porosity when a large layer thicknesses was used,and the porosity disappeared by reducing the layer thickness or laser energy input.A deeper keyhole penetration was found in all occasions with porosity,explaining the influence of layer thickness,geometrical structure,and laser energy input on the porosity.All the samples achieved a high fusion quality with a relative density of over 99.5%using the optimized laser energy input.The increased layer thickness resulted to more precipitation phases,finer grain sizes and decreased grain texture.With the similar high fusion quality,the tensile strength and elongation of bulk samples were significantly improved from 257 MPa and 1.41%with the 10μm layer to 287 MPa and 15.12%with the 40μm layer,in accordance with the microstructural change.The effect of layer thickness on the compressive properties of porous scaffolds was limited.However,the corrosion rate of bulk samples accelerated with increasing the layer thickness,mainly attributed to the increased number of precipitation phases.展开更多
Laser powder bed fusion(L-PBF)has been employed to additively manufacture WE43 magnesium(Mg)alloy biodegradable implants,but WE43 L-PBF samples exhibit excessively rapid corrosion.In this work,dense WE43 L-PBF samples...Laser powder bed fusion(L-PBF)has been employed to additively manufacture WE43 magnesium(Mg)alloy biodegradable implants,but WE43 L-PBF samples exhibit excessively rapid corrosion.In this work,dense WE43 L-PBF samples were built with the relativity density reaching 99.9%.High temperature oxidation was performed on the L-PBF samples in circulating air via various heating temperatures and holding durations.The oxidation and diffusion at the elevated temperature generated a gradient structure composed of an oxide layer at the surface,a transition layer in the middle and the matrix.The oxide layer consisted of rare earth(RE)oxides,and became dense and thick with increasing the holding duration.The matrix was composed ofα-Mg,RE oxides and Mg_(24)RE_(5) precipitates.The precipitates almost disappeared in the transition layer.Enhanced passivation effect was observed in the samples treated by a suitable high temperature oxidation.The original L-PBF samples lost 40%weight after 3-day immersion in Hank’s solution,and broke into fragments after 7-day immersion.The casted and solution treated samples lost roughly half of the weight after 28-day immersion.The high temperature oxidation samples,which were heated at 525℃ for 8 h,kept the structural integrity,and lost only 6.88%weight after 28-day immersion.The substantially improved corrosion resistance was contributed to the gradient structure at the surface.On one hand,the outmost dense layer of RE oxides isolated the corrosive medium;on the other hand,the transition layer considerably inhibited the corrosion owing to the lack of precipitates.Overall,high temperature oxidation provides an efficient,economic and safe approach to inhibit the corrosion of WE43 L-PBF samples,and has promising prospects for future clinical applications.展开更多
Laminectomy is one of the most common posterior spinal operations. Since the lamina is adjacent to important tissues such as nerves, once damaged, it can cause serious com-plications and even lead to paralysis. In ord...Laminectomy is one of the most common posterior spinal operations. Since the lamina is adjacent to important tissues such as nerves, once damaged, it can cause serious com-plications and even lead to paralysis. In order to prevent the above injuries and com-plications, ultrasonic bone scalpel and surgical robots have been introduced into spinal laminectomy, and many scholars have studied the recognition method of the bone tissue status. Currently, almost all methods to achieve recognition of bone tissue are based on sensor signals collected by high‐precision sensors installed at the end of surgical robots. However, the previous methods could not accurately identify the state of spinal bone tissue. Innovatively, the identification of bone tissue status was regarded as a time series classification task, and the classification algorithm LSTM‐FCN was used to process fusion signals composed of force and cutting depth signals, thus achieving an accurate classi-fication of the lamina bone tissue status. In addition, it was verified that the accuracy of the proposed method could reach 98.85% in identifying the state of porcine spinal laminectomy. And the maximum penetration distance can be controlled within 0.6 mm, which is safe and can be used in practice.展开更多
Laser powder bed fusion(L-PBF)has been used to fabricate biodegradable Mg implants of WE43 alloy,but the degradation is too fast compared with the term bone reconstruction.Previous studies show that high temperature o...Laser powder bed fusion(L-PBF)has been used to fabricate biodegradable Mg implants of WE43 alloy,but the degradation is too fast compared with the term bone reconstruction.Previous studies show that high temperature oxidation(HTO)can successfully inhibit the degradation of WE43 alloy.In this work,the influence of HTO on L-PBF samples of WE43 alloy was investigated regarding tensile,compressive,and abrasive resistance,as well as in vitro cytotoxicity,cell proliferation,hemolysis,and osteogenesis.Compared with the as-built L-PBF samples,HTO increased grain size and grain texture,stabilized and coarsened precipitates,and caused discontinuous static recrystallization in the matrix.The oxide layer at the surface of the HTO samples improved surface roughness,hydrophilia,hardness,and abrasive resis-tance.The tensile strength decreased slightly from 292 to 265 MPa,while the elongation substantially increased from 10.97%to 16.58%after HTO.The in vitro cell viability,cell proliferation,hemolysis,and osteogenic effect were considerably enhanced due to the improvement of surface quality and the initial inhibition of excessive Mg^(2+)releasement.Overall,HTO is of great benefit to the surface performance,ductility,and biocompatibility of WE43 alloy fabricated by L-PBF for biodegradable applications.展开更多
To eliminate unnecessary background information,such as soft tissues in original CT images and the adverse impact of the similarity of adjacent spines on lumbar image segmentation and surgical path planning,a two‐sta...To eliminate unnecessary background information,such as soft tissues in original CT images and the adverse impact of the similarity of adjacent spines on lumbar image segmentation and surgical path planning,a two‐stage approach for localising lumbar segments is proposed.First,based on the multi‐scale feature fusion technology,a non‐linear regression method is used to achieve accurate localisation of the overall spatial region of the lumbar spine,effectively eliminating useless background information,such as soft tissues.In the second stage,we directly realised the precise positioning of each segment in the lumbar spine space region based on the non‐linear regression method,thus effectively eliminating the interference caused by the adjacent spine.The 3D Intersection over Union(3D_IOU)is used as the main evaluation indicator for the positioning accuracy.On an open dataset,3D_IOU values of 0.8339�0.0990 and 0.8559�0.0332 in the first and second stages,respectively is achieved.In addition,the average time required for the proposed method in the two stages is 0.3274 and 0.2105 s respectively.Therefore,the proposed method performs very well in terms of both pre-cision and speed and can effectively improve the accuracy of lumbar image segmentation and the effect of surgical path planning.展开更多
BACKGROUND Scoliosis is a complex three-dimensional deformity of spine and one of the common complications of collagen VI-related myopathy,caused by mutations in collagen type VI alpha 1 chain(COL6A1),COL6A2,and COL6A...BACKGROUND Scoliosis is a complex three-dimensional deformity of spine and one of the common complications of collagen VI-related myopathy,caused by mutations in collagen type VI alpha 1 chain(COL6A1),COL6A2,and COL6A3 genes.The typical clinical presentations of collagen VI-related myopathy include weakness,hypotonia,laxity of distal joints,contractures of proximal joints,and skeletal deformities.CASE SUMMARY A 28-year-old female presented with scoliosis for 28 years without weakness,hypotonia,laxity of distal joints,and contracture of proximal joints.Computed tomography and magnetic resonance imaging revealed hemivertebra,butterfly vertebra,and the missing vertebral space.Patients underwent orthopedic surgery and paravertebral muscle biopsy.The Cobb angle dropped from 103.4°to 52.9°.However,the muscle biopsy showed neurogenic muscular atrophy with myogenic lesions,suggesting congenital muscular dystrophy.Gene analysis indicated that mutations in COL6A1(c.1612-10G>A)and COL6A2(c.115+10G>T,c.2749G>A).Immunohistochemistry staining for collagen VI displayed shallow and discontinuous.Eventually,the patient was diagnosed as collagen VI-related myopathy.CONCLUSION This newly found subtype of collagen VI-related myopathy has no typical manifestations;however,it is characterized by severe scoliosis and congenital vertebral deformity.展开更多
Reconstruction of subarticular bone defects is an intractable challenge in orthopedics.The simultaneous repair of cancellous defects,fractures,and cartilage damage is an ideal surgical outcome.3D printed porous anatom...Reconstruction of subarticular bone defects is an intractable challenge in orthopedics.The simultaneous repair of cancellous defects,fractures,and cartilage damage is an ideal surgical outcome.3D printed porous anatomical WE43(magnesium with 4 wt%yttrium and 3 wt%rare earths)scaffolds have many advantages for repairing such bone defects,including good biocompatibility,appropriate mechanical strength,customizable shape and structure,and biodegradability.In a previous investigation,we successfully enhanced the corrosion resistance of WE43 samples via high temperature oxidation(HTO).In the present study,we explored the feasibility and effectiveness of HTO-treated 3D printed porous anatomical WE43 scaffolds for repairing the cancellous bone defects accompanied by split fractures via in vitro and in vivo experiments.After HTO treatment,a dense oxidation layer mainly composed of Y2O3 and Nd2O3 formed on the surface of scaffolds.In addition,the majority of the grains were equiaxed,with an average grain size of 7.4μm.Cell and rabbit experiments confirmed the non-cytotoxicity and biocompatibility of the HTO-treated WE43 scaffolds.After the implantation of scaffolds inside bone defects,their porous structures could be maintained for more than 12 weeks without penetration and for more than 6 weeks with penetration.During the postoperative follow-up period for up to 48 weeks,radiographic examinations and histological analysis revealed that abundant bone gradually regenerated along with scaffold degradation,and stable osseointegration formed between new bone and scaffold residues.MRI images further demonstrated no evidence of any obvious damage to the cartilage,ligaments,or menisci,confirming the absence of traumatic osteoarthritis.Moreover,finite element analysis and biomechanical tests further verified that the scaffolds was conducive to a uniform mechanical distribution.In conclusion,applying the HTO-treated 3D printed porous anatomical WE43 scaffolds exhibited favorable repairing effects for subarticular cancellous bone defects,possessing great potential for clinical application.展开更多
Background Icafiine is a flavonoid isolated from a traditional Chinese medicine Epimedium pubescens and is the main active compound of it. Recently, Epimedium pubescens was found to have a therapeutic effect on osteop...Background Icafiine is a flavonoid isolated from a traditional Chinese medicine Epimedium pubescens and is the main active compound of it. Recently, Epimedium pubescens was found to have a therapeutic effect on osteoporosis. But the mechanism is unclear. The aim of the study was to research the effect of Icariine on the proliferation and differentiation of human osteoblasts. Methods Human osteoblasts were obtained by inducing human marrow mesenchymal stem cells （hMSCs） directionally and were cultured in the presence of vadous concentrations of Icariine. 3-（4,5-dimethylthiazol-2-yl）-2,5- diphenyltetrazolium bromide （MTT） test was used to observe the effect of Icariine on cell proliferation. The activity of alkaline phosphatase （ALP） and the amount of calcified nodules were assayed to observe the effect on cell differentiation. The expression of bone morphogenetic protein 2 （BMP-2） mRNA was detected by reverse transcriptase-polymerase chain reaction （RT-PCR）. Results Icadine （20 μg/ml） increased significantly the proliferation of human osteoblasts. And, IcarUne （10 μg/ml and 20 μg/ml） increased the activity of ALP and the amount of calcified nodules of human osteoblasts significantly （P〈0.05）. BMP-2 mRNA synthesis was elevated significantly in response to Icariine （20 μg/ml）. Conclusions Icadine has a direct stimulatory effect on the proliferation and differentiation of cultured human osteoblast cells in vitro, which may be mediated by increasing production of BMP-2 in osteoblasts.展开更多
Background There has been an increasing recognition of the importance of sagittal spinopelvic alignment in patients with scoliosis as it relates to clinical outcomes. However, the changes seen in sagittal spinopelvic ...Background There has been an increasing recognition of the importance of sagittal spinopelvic alignment in patients with scoliosis as it relates to clinical outcomes. However, the changes seen in sagittal spinopelvic alignment in adult idiopathic scoliosis patients is poorly defined. This study was conducted to evaluate the sagittal alignment of pelvis and spine in adult idiopathic scoliosis patients.Methods The sagittal parameters of the spine and pelvis were analyzed in lateral standing radiographs of 124 patients （mean age 47.4 years） with adult idiopathic scoliosis, including thoracic kyphosis （TK）, thoracolumbar junction kyphosis （TLJ）, lumbar lordosis （LL）, pelvic incidence （PI）, sacrum slope （SS）, pelvic tilt （PT） and C7 plumb line （C7PL）. The patients were divided into three groups according to the age： 20-40 years, 41-64 years, and ≥65 years. The parameters were compared with those in normal adults and adolescent idiopathic scoliosis （AIS） patients. The relationship between all parameters as well as age and sagittal parameters were analyzed.Results The PI in patients with adult idiopathic scoliosis was 58.1°±13.0°, which was significantly higher than that in normal adults. The PT （19.9°±10.6°） was also higher than that in both normal adults and AIS patients, while the SS （38.1°±12.0°） was similar or smaller. As age increased, C7PL, PT and TJL increased while LL decreased. There was no relationship between age and both PI and TK. PT had the strongest statistical association with the C7PL.Conclusions PI is higher in adult idiopathic scoliosis than normal subjects. The PT is the most relevant pelvic parameter to the global sagittal alignment of the spine. Age significantly influences sagittal parameters of the spine and pelvis except the PI and TK.展开更多
Background:Finding an optimal treatment strategy for adolescent idiopathic scoliosis(AIS)patients remains challenging because of its intrinsic complexity.For mild to moderate scoliosis patients with lower skeletal gro...Background:Finding an optimal treatment strategy for adolescent idiopathic scoliosis(AIS)patients remains challenging because of its intrinsic complexity.For mild to moderate scoliosis patients with lower skeletal growth potential(Risser 3-5),most clinicians agree with observation treatment;however,the curve progression that occurs during puberty,the adolescent period,and even in adulthood,remains a challenging issue for clinicians.The aim of the study is to investigate the efficacy of Schroth exercise in AIS patients with lower skeletal growth potential(Risser 3-5)and moderate scoliosis(Cobb angle 20°-40°).Methods:From 2015 to 2017,data of 64 patients diagnosed with AIS in Peking University Third Hospital were reviewed.Forty-three patients underwent Schroth exercise were classified as Schroth group,and 21 patients underwent observation were classified as observation group.Outcomes were measured by health-related quality of life(HRQOL)and radiographic parameters.HRQOL was assessed using the visual analog scale(VAS)scores for back,Scoliosis Research Society-22(SRS-22)patient questionnaire.Radiographic spinopelvic parameters were obtained from anteroposterior and lateral X-rays.The pre-treatment and post-treatment HRQOL and radiographic parameters were tested to validate Schroth exercise efficacy.The inter-rater reliability of the radiographic parameters was tested using the interclass correlation coefficient(ICC).The pairedt test was used to examine HRQOL and radiographic parameters.Clinical relevance between C2-C7 sagittal vertical axis(SVA)and thoracic kyphosis was analyzed using Spearman correlation.Results:In Schroth group,VAS back score,SRS-22 pain,and SRS-22 self-image domain were significantly improved from pre-treatment 3.0±0.8,3.6±0.5,and 3.5±0.7 to post-treatment 1.6±0.6(t=5.578,P=0.013),4.0±0.3(t=-3.918,P=0.001),and 3.7±0.4(t=-6.468,P<0.001),respectively.No significant improvements of SRS-22 function domain(t=-2.825,P=0.088)and mental health domain(t=-3.174,P=0.061)were observed.The mean Cobb angle decreased from 28.9±5.5°to 26.3±5.2°at the final follow-up,despite no statistical significance was observed(t=1.853,P=0.102).The mean C2-C7 SVA value decreased from 21.7±8.4 mm to 17.0±8.0 mm(t=-1.224P=0.049)and mean T1 tilt decreased from 4.9±4.2°to 3.5±3.1°(t=2.913,P=0.011).No significant improvement of radiographic parameters and HRQOL were observed in observation group.Conclusions:For AIS patients with a Risser 3-5 and a Cobb angle 20°-40°,Schroth exercises improved HRQOL and halted curve progression during the follow-up period.Both cervical spine alignment and shoulder balance were also significantly improved after Schroth exercises.We recommend Schroth exercises for patients with AIS.展开更多
Background： Total knee arthroplasty （TKA） is the most frequently performed procedure in treating advanced knee osteoarthritis. Excessive perioperative blood loss can sometimes lead to postoperative anemia. Tranexam...Background： Total knee arthroplasty （TKA） is the most frequently performed procedure in treating advanced knee osteoarthritis. Excessive perioperative blood loss can sometimes lead to postoperative anemia. Tranexamic acid （TXA） is a potent fibrinolysis inhibitor which has been extensively used at the surgical incision and closure to lower overall blood loss in adult reconstruction surgery. Our previous study suggested that about two-thirds of the total blood loss （TBL） came from hidden blood loss （HBL） on postoperative days 1 and 2. The role of reducing HBL with TXA administration in postoperative TKA patients is unknown. The current study was designed to evaluate the efficiency and safety of supplemental intravenous （IV） TXA in further redticing HBL after primary TKA. Methods： A prospective pilot study was conducted at a single institution on 43 consecutive patients who underwent unilateral TKA from September 2014 to February 2015. All patients were given 1 g of IV TXA 10-15 rain before operation and another 1 g of IV TXA at the time of wound closure on the day of surgery. On postoperative days 1 and 2, the supplemental group （n = 21） was given additional 1 g of TXA intravenously twice a day, whereas the control group （n = 22） received an equal volume of saline. Drain output, hemoglobin （Hb）, and hematocrit （HCT） were recorded preoperatively and 5 consecutive days postoperatively in both groups. HBL was calculated with the Gross formula. Pre- and post-operative lower extremity Doppler venous ultrasound was performed in all patients to detect deep vein thrombosis （DVT）. The indexes were compared using the Mann-Whitney test, whereas the results of Hb and HCT were analyzed by repeated-measures analysis of variance. The difference was considered statistically significant ifP 〈 0.05. Results： The demographics and surgical characteristics of the two groups were comparable. Supplemental group had higher Hb level on postoperative days 1-5 compared to the control; however, the difference was not significant （F = 2.732, P = 0.106）. The HCT of the supplemental group was significantly higher than that of the control group on postoperative day 5 （F= 5.254, P = 0.027）. No significant difference was found in drainage volume and TBL, but the HBL was reduced in the supplemental group （supplemental 133.1 [71.8,287.3] ml and control 296.0 [ 185.3, 421.4] ml, Z = 2.478, P = 0.013. median [interquartile range]）. There was one DVT in the control group and none in the supplemental group. All patients were tbllowed at 1 year after surgery, and no further complications were reported. Conclusion： Based on the current study, additional doses of IV TXA could potentially further reduce HBL alter primary TKA without increasing the risk of venous thromboembolism.展开更多
Background This study investigated the relationship between the height of osteotomy and the correction of the kyphotic angle during posterior closing wedge osteotmy with instrumentation and the spinal osteotomy with c...Background This study investigated the relationship between the height of osteotomy and the correction of the kyphotic angle during posterior closing wedge osteotmy with instrumentation and the spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach in thoracolumbar kyphosis, and using this relationship as the basis of the preoperative design. Methods From April 1996 to June 2007, 30 thoracolumbar kyphosis patients with complete medical records and clear X-ray photograms have undergone operation. Of these 30 cases, 16 cases underwent posterior closing wedge osteotmy with instrumentation while the height of the osteotomy and the correction of the angle have been measured; 14 cases underwent spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach while the height of the osteotomy, the height and the place of the cage and the correction of the angle were also measured. A simple geometrical model was simulated to calculate the relationship between the height of the oeteotomy and the correction of the angle and these results are finally compared with the data coming from the actual measuring by the Wilcoxon statistic method. Results The distribution of data from the 16 cases by posterior closing wedge osteotomy with instrumentation was as such： 9 male and 7 female, the mean age was 49.2 years （range 38--70）, the kyphosis improved from an average of 30° （range 15°--45°） preoperatively to 4° （range -26°--30°） postoperatively, the kyphosis was corrected on average 2.5-0 per 1 mm in the height of the osteotomy. The results from the simple geometrical model were that the mean of the correction of the angle per 1 mm was 2.2°. As a result, there was no significant difference （P 〉0.05） when comparing the measurement collected with the result simulated from the geometric model. The distribution of data from the 14 cases by spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach was as such： 5 male and 9 female, the mean age was 35.3 years old （range 15--57）, the kyphosis improved from an average of 64°- （range 34°--95°） preoperatively to 8.70 （range -10°--22°） postoperatively. The kyphosis was corrected on average of 6.2°- per 1 mm in the height of the psteotomy. The results from the simple geometrical model is that the mean of the correction of the angle per 1 mm was 6.6°. There was also no significant difference （P 〉0.05） when comparing the measurement collected with the result simulated from the geometric model. Conclusions The therapeutic effect is significant for both posterior closing wedge osteotomy with instrumentation and spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach. The posterior closing wedge osteotomy with instrumentation is an easier approach with the mean angle of the correction per 1 mm of 2.5°- and the maximum angle of correction of 45°. The spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach is more efficient with the mean angle of correction per I mm of 6.2°. It should be reserved for the severe cases of thoracolumbar kyphosis. We can also use the formula to held us constructing Preoperative desiqn.展开更多
Background Chordomas of the upper cervical spine are rare and present unique surgical challenge.This study aimed to describe the clinical characteristics and surgical management of patients with chordomas of the upper...Background Chordomas of the upper cervical spine are rare and present unique surgical challenge.This study aimed to describe the clinical characteristics and surgical management of patients with chordomas of the upper cervical spine.Methods Twenty-one patients with chordomas of the upper cervical spine who were treated in Peking University Third Hospital from January 1999 to October 2012 were retrospectively analyzed.Survival was calculated by the Kaplan-Meier method and was compared between groups using the log-rank test.Results The postoperative diagnosis was classical chordoma in 20 cases and chondroid chordoma in one case.The mean operative time was 9.5 hours （range 6-17 hours）,and the mean blood loss was 2 812 ml （range 700-4 800 ml）.There were two postoperative deaths.Unilateral vertebral artery ligation was performed in six patients,cervical nerve roots were cut in six patients,and the external branch of the superior laryngeal nerve was repaired after being cut in one case.Two patients developed postoperative velopharyngeal incompetence,and loosening of the occipitocervical screws was observed in one patient.The recurrence rate was 66.7% （10/15） after a mean follow-up period of 46.8 months （range 14-150 months）.The 5-and 10-year overall survival rates were （39.8±13.1）% and （31.9±12.7）%,respectively.There was a significant difference in survival rate between patients who underwent surgery and those who did not.Conclusion In spite of the high rates of recurrence and complications after surgical treatment of chordomas of the upper cervical spine,intralesional resection combined with adjuvant radiotherapy remains the optimal treatment to prolong survival.展开更多
Background Accurate knowledge of the spinal structural functions is critical to understand the biomechanical factors that affect spinal pathology. Many studies have investigated the human vertebral motion both in vitr...Background Accurate knowledge of the spinal structural functions is critical to understand the biomechanical factors that affect spinal pathology. Many studies have investigated the human vertebral motion both in vitro and in vivo. However, determination of in vivo motion of the vertebrae under physiologic loading conditions remains a challenge in biomedical engineering because of the limitations of current technology and the complicated anatomy of the spine. Methods For in vitro validation, a human lumbar specimen was imbedded with steel beads and moved to a known distance by an universal testing machine （UTM）.展开更多
Background： Giant cell tumors （GCTs） are benign, locally aggressive tumors. We exalnined the rate of local rectirrence of spinal GCTs and sought to identify recurrence factors in patients who underwent surgery. Met...Background： Giant cell tumors （GCTs） are benign, locally aggressive tumors. We exalnined the rate of local rectirrence of spinal GCTs and sought to identify recurrence factors in patients who underwent surgery. Methods： Between 1995 and 2014, 94 mobile spine GCT patients were treated at our hospital, comprising 43 male and 51 female patients with an average age of 33.4 years. Piecemeal intralesional spondylectomy and total en bloc spondylectomy （TES） were performed. Radiotherapy was suggested for recurrent or residual GCT cases. Since denosumab was not available before 2014 in our country, only interferon and/or zoledronic acid was suggested. Results： Of the 94 patients, four underwent conservative treatment and 90 underwent operations. Seventy-five patients （79.8%） were followed tip for a minimum of 24 months or until death. The median follow-up duration was 75.3 months. The overall recurrence rate was 37.3%. Ten patients （13.3%） died before the last follow-up （rnedian： 18.5 months）. Two patients （2.6%） developed osteogenic sarcoma. The local recurrence rate was 80.0% （24/30） in patients who underwent intralesional curettage, 8.8% （3/34） in patients who underwent extracapsular piecemeal spondylectomy,and 0 （0/9） in patients who underwent TES. The risk factors for local recurrence were lesions located in the cervical spine （P = 0.049）, intralesional curettage （P 〈 0.001 ）, repeated surgeries （P 0.014）, and malignancy （P 〈 0.001 ）. Malignant transformation was a significant risk factor for death （P 〈 0.001 ）. Conclusions： Cervical spinal tumors, curettage, and nonintact tumors were risk l;actors for local recurrence. Intralesional curettage and malignancy were the most important significant factors for local rectirrence and death, respectively.展开更多
Background This retrospective study aimed to investigate the difference of the intra-dural reserving space for spinal cord in magnetic resonance imaging （MRI） between patients with and without developmental cervical...Background This retrospective study aimed to investigate the difference of the intra-dural reserving space for spinal cord in magnetic resonance imaging （MRI） between patients with and without developmental cervical stenosis and its clinical significance.Methods A total of 264 patients with cervical spondylotic myelopathy who had decompression surgeries were recruited.The average follow-up was 29 months.Based on their lateral radiographs,they were divided into stenosis group and non-stenosis group.On the magnetic resonance images,the ratio of the sagittal diameter of the dural sac to that of the vertebral body was measured and calculated as MRI Pavlov ratio at the mid-vertebral level on T2-weighted sagittal images from C3 to C7.The ratio of the transverse area of the spinal cord to that of the dural sac was measured and calculated as occupation ratio on T2-weighted axial images at the same levels.The MRI Pavlov ratio and occupation ratio were compared between the two groups.The stenosis group was further divided into space-reserving and non-space-reserving subgroups based on the occupation ratios; then clinical parameters were compared between the two subgroups to determine the clinical significance of the reserving space.Results The MRI Pavlov ratio of the stenosis group was significantly smaller than that of the non-stenosis group at C3-C7 （P ＜0.01）,while the occupation ratio was significantly larger only at C7 （P ＜0.05）.For the space-reserving subgroup,the postoperative recovery rate was lower （P ＜0.05）.The postoperative recovery rate was （23±6）％ in anterior approach,larger than （-23±15）％ in posterior approach （P ＜0.05）.Conclusions Developmental cervical stenosis is associated with a smaller sagittal diameter of the dural sac,but does not lead to a significant decrease in intra-dural space available for the cord.For patients with normal intra-dural space,the recovery after anterior decompression surgery was better than posterior approach.展开更多
Background The treatment strategies for multilevel thoracic ossification of the posterior longitudinal ligaments （T-OPLL） were rarely reported. The aim of this study was to investigate the clinical outcomes and comp...Background The treatment strategies for multilevel thoracic ossification of the posterior longitudinal ligaments （T-OPLL） were rarely reported. The aim of this study was to investigate the clinical outcomes and complications of circumferential decompression for multilevel T-OPLL and compare two different methods in the management of the OPLL （resection or floating）. Methods Data of sequentially treated patients who received surgical treatment for thoracic spinal stenosis caused by multilevel T-OPLL from January 2005 to February 2012 were retrospectively reviewed. Based on the surgical approaches applied, the patients were divided into two groups. Group A consisted the patients who received posterior decompression and group B consisted the patients who received circumferential decompression via the posterior approach. Group B was further divided into two subgroups： subgroup 1 （the resection group） where the OPLL was completely resected and subgroup 2 （the floating group） where the OPLL was floated. Results A total of 49 patients were included in the study. Fourteen patients with single posterior decompression were included in group A and 35 patients who received circumferential decompression were included in group B. In group B, 29 patients had complete resection of the ossified posterior longitudinal ligaments, while the other six underwent a flotation procedure. The follow-up data were available in 39 patients. Mean JOA scores improved from 5.4 ± 1.8 to 7.5 ± 2.8 in group A and from 3.7 ± 1.8 to 7.9 ± 2.4 in group B. The main complications included cerebrospinal fluid （CSF） leakage and postoperative neurelogic deterioration （ND）. Twenty-three of the 25 cases with postoperative CSF leakage achieved a complete recovery at the last follow-up and 12 of the 15 cases with ND achieved some neurological improvement at the last follow-up. Conclusions Circumferential decompression via the posterior approach is an effective surgical method for thoracic spinal stenosis caused by multilevel OPLL of the thoracic spine. Patients who receive complete resection of the ossified posterior longitudinal ligaments may have better recovery rate than the ＂floating＂ group.展开更多
Diffuse-type tenosynovial giant cell tumor （D-TGCT） belongs to a group of lesions believed to arise from tendon sheaths,bursae,or the synovium of diarthrodial joints.The etiology of D-TGCT is unknown.Because it shar...Diffuse-type tenosynovial giant cell tumor （D-TGCT） belongs to a group of lesions believed to arise from tendon sheaths,bursae,or the synovium of diarthrodial joints.The etiology of D-TGCT is unknown.Because it shares histological characteristics with pigmented villonodular synovitis,however,D-TGCT is also termed extra-articular pigmented villonodular synovitis.D-TGCT,which occurs mainly in middle-aged women （20-50 years of age1）,usually involves large load-bearing joints （e.g.,knee,ankle,and hip）.Clinical case reports of D-TGCT involving the spine are rare.2 We retrospectively analyzed a series of three patients diagnosed with cervical D-TGCT in our department over a 10-year period.展开更多
Background Differentiated thyroid cancer （DTC） is a common primary cancer for spinal metastases （SM）.The treatments for DTC spinal metastases （SM） have evolved from simple surgery and radiotherapy to a multidisc...Background Differentiated thyroid cancer （DTC） is a common primary cancer for spinal metastases （SM）.The treatments for DTC spinal metastases （SM） have evolved from simple surgery and radiotherapy to a multidisciplinary comprehensive therapeutic strategy of combined spinal surgery,general surgery,radiotherapy,nuclear medicine and endocrinology.The purpose of this study was to discuss the efficacy and prognosis associated with different surgical treatments of SM patients with DTC.Methods A total of 21 consecutive patients with SM of DTC that were treated between 1999 and 2013 were studied.Biopsy was routinely performed to achieve the pathological diagnosis before treatment.Three patients underwent total spondylectomy intralesionally or piecemeally,and 18 had curettage.Postoperative recurrence and survival times were analyzed by the Kaplan-Meier methods.Results Nineteen patients （90％） had an average of 42.7 months （range,7-170 months） follow-up.The median visual analogue scale for pain reduced from 5 points to 1 point （P ＜0.01）,and the median Karnofsky performance score increased from 70 to 90 points after surgery （P ＜0.01）.Seventeen patients with neurological deficits attained improvements after surgeries,of at least one level according to the Frankel classification （P ＜0.01）.Eight patients with curettage had recurrence.Four patients died of DTC,12 patients lived with disease,and three patients were disease-free.No significant effects on postoperative recurrence or survival were observed between surgery combined with conservative treatment,total spondylectomy,the number of bone metastases and visceral metastasis.Conclusions DTC-SM have a relatively favorable prognosis,and curettage and stabilization can effectively relieve the pain and improve the quality of life and neurological status of the patients.For patients with Tomita scores of ＜3,total spondylectomy may have better clinical outcomes.Comprehensive therapeutic strategies including surgery,radioiodine,external beam radiation therapy and embolization should be considered for most patients.展开更多
基金supported by Beijing Municipal Science and Technology Project(Z201100005520073)Key Clinical projects of Peking University Third hospital(BYSY2022064)+1 种基金China Postdoctoral Science Foundation(M2023740146)National Natural Science Foundation of China(82302731).
文摘Due to matching biomechanical properties and significant biological activity,Mg-based implants present great potential in orthopedic applications.In recent years,the biocompatibility and therapeutic effect of magnesiumbased implants have been widely investigated in trauma repair.In contrast,the R&D work of Mg-based implants in spinal fusion is still limited.This review firstly introduced the general background for Mg-based implants.Secondly,the mechanical properties and degradation behaviors of Mg and its traditional and novel alloys were reviewed.Then,different surface modification techniques of Mg-based implants were described.Thirdly,this review comprehensively summarized the biological pathways of Mg degradation to promote bone formation in neuro-musculoskeletal circuit,angiogenesis with H-type vessel formation,osteogenesis with osteoblasts activation and chondrocyte ossification as an integrated system.Fourthly,this review followed the translation process of Mg-based implants via updating the preclinical studies in fracture fixation,sports trauma repair and reconstruction,and bone distraction for large bone defect.Furthermore,the pilot clinical studies were involved to demonstrate the reliable clinical safety and satisfactory bioactive effects of Mg-based implants in bone formation.Finally,this review introduced the background of spine fusion surgeryand the challenges of biological matching cage development.At last,this review prospected the translation potential of a hybrid Mg-PEEK spine fusion cage design.
基金funded by the National Key Research and Development Program of China(2018YFE0104200)National Natural Science Foundation of China(51875310,52175274,82172065)Tsinghua Precision Medicine Foundation.
文摘Laser powder bed fusion(L-PBF)of Mg alloys has provided tremendous opportunities for customized production of aeronautical and medical parts.Layer thickness(LT)is of great significance to the L-PBF process but has not been studied for Mg alloys.In this study,WE43 Mg alloy bulk cubes,porous scaffolds,and thin walls with layer thicknesses of 10,20,30,and 40μm were fabricated.The required laser energy input increased with increasing layer thickness and was different for the bulk cubes and porous scaffolds.Porosity tended to occur at the connection joints in porous scaffolds for LT40 and could be eliminated by reducing the laser energy input.For thin wall parts,a large overhang angle or a small wall thickness resulted in porosity when a large layer thicknesses was used,and the porosity disappeared by reducing the layer thickness or laser energy input.A deeper keyhole penetration was found in all occasions with porosity,explaining the influence of layer thickness,geometrical structure,and laser energy input on the porosity.All the samples achieved a high fusion quality with a relative density of over 99.5%using the optimized laser energy input.The increased layer thickness resulted to more precipitation phases,finer grain sizes and decreased grain texture.With the similar high fusion quality,the tensile strength and elongation of bulk samples were significantly improved from 257 MPa and 1.41%with the 10μm layer to 287 MPa and 15.12%with the 40μm layer,in accordance with the microstructural change.The effect of layer thickness on the compressive properties of porous scaffolds was limited.However,the corrosion rate of bulk samples accelerated with increasing the layer thickness,mainly attributed to the increased number of precipitation phases.
基金funded by the National Key Research and Development Program of China (2018YFE0104200)National Natural Science Foundation of China (51875310, 52175274, 82172065)Tsinghua Precision Medicine Foundation
文摘Laser powder bed fusion(L-PBF)has been employed to additively manufacture WE43 magnesium(Mg)alloy biodegradable implants,but WE43 L-PBF samples exhibit excessively rapid corrosion.In this work,dense WE43 L-PBF samples were built with the relativity density reaching 99.9%.High temperature oxidation was performed on the L-PBF samples in circulating air via various heating temperatures and holding durations.The oxidation and diffusion at the elevated temperature generated a gradient structure composed of an oxide layer at the surface,a transition layer in the middle and the matrix.The oxide layer consisted of rare earth(RE)oxides,and became dense and thick with increasing the holding duration.The matrix was composed ofα-Mg,RE oxides and Mg_(24)RE_(5) precipitates.The precipitates almost disappeared in the transition layer.Enhanced passivation effect was observed in the samples treated by a suitable high temperature oxidation.The original L-PBF samples lost 40%weight after 3-day immersion in Hank’s solution,and broke into fragments after 7-day immersion.The casted and solution treated samples lost roughly half of the weight after 28-day immersion.The high temperature oxidation samples,which were heated at 525℃ for 8 h,kept the structural integrity,and lost only 6.88%weight after 28-day immersion.The substantially improved corrosion resistance was contributed to the gradient structure at the surface.On one hand,the outmost dense layer of RE oxides isolated the corrosive medium;on the other hand,the transition layer considerably inhibited the corrosion owing to the lack of precipitates.Overall,high temperature oxidation provides an efficient,economic and safe approach to inhibit the corrosion of WE43 L-PBF samples,and has promising prospects for future clinical applications.
基金National Key Research and Development Program of China,Grant/Award Number:2022YFB4700700Beijing‐tianjin‐hebei,Grant/Award Number:J230020。
文摘Laminectomy is one of the most common posterior spinal operations. Since the lamina is adjacent to important tissues such as nerves, once damaged, it can cause serious com-plications and even lead to paralysis. In order to prevent the above injuries and com-plications, ultrasonic bone scalpel and surgical robots have been introduced into spinal laminectomy, and many scholars have studied the recognition method of the bone tissue status. Currently, almost all methods to achieve recognition of bone tissue are based on sensor signals collected by high‐precision sensors installed at the end of surgical robots. However, the previous methods could not accurately identify the state of spinal bone tissue. Innovatively, the identification of bone tissue status was regarded as a time series classification task, and the classification algorithm LSTM‐FCN was used to process fusion signals composed of force and cutting depth signals, thus achieving an accurate classi-fication of the lamina bone tissue status. In addition, it was verified that the accuracy of the proposed method could reach 98.85% in identifying the state of porcine spinal laminectomy. And the maximum penetration distance can be controlled within 0.6 mm, which is safe and can be used in practice.
基金National Key Research and Development Program of China(No.2018YFE0104200)National Natural Science Foundation of China(Nos.52175274,82172065,51875310)Tsinghua Precision Medicine Foundation and Tsinghua-Toyota Joint Research Fund.
文摘Laser powder bed fusion(L-PBF)has been used to fabricate biodegradable Mg implants of WE43 alloy,but the degradation is too fast compared with the term bone reconstruction.Previous studies show that high temperature oxidation(HTO)can successfully inhibit the degradation of WE43 alloy.In this work,the influence of HTO on L-PBF samples of WE43 alloy was investigated regarding tensile,compressive,and abrasive resistance,as well as in vitro cytotoxicity,cell proliferation,hemolysis,and osteogenesis.Compared with the as-built L-PBF samples,HTO increased grain size and grain texture,stabilized and coarsened precipitates,and caused discontinuous static recrystallization in the matrix.The oxide layer at the surface of the HTO samples improved surface roughness,hydrophilia,hardness,and abrasive resis-tance.The tensile strength decreased slightly from 292 to 265 MPa,while the elongation substantially increased from 10.97%to 16.58%after HTO.The in vitro cell viability,cell proliferation,hemolysis,and osteogenic effect were considerably enhanced due to the improvement of surface quality and the initial inhibition of excessive Mg^(2+)releasement.Overall,HTO is of great benefit to the surface performance,ductility,and biocompatibility of WE43 alloy fabricated by L-PBF for biodegradable applications.
基金Original Innovation Joint Fund:L202010 and the National Key Research and Development Program of China:2018YFB1307604National Key Research and Development Program of China,Grant/Award Numbers:2018YFB1307604。
文摘To eliminate unnecessary background information,such as soft tissues in original CT images and the adverse impact of the similarity of adjacent spines on lumbar image segmentation and surgical path planning,a two‐stage approach for localising lumbar segments is proposed.First,based on the multi‐scale feature fusion technology,a non‐linear regression method is used to achieve accurate localisation of the overall spatial region of the lumbar spine,effectively eliminating useless background information,such as soft tissues.In the second stage,we directly realised the precise positioning of each segment in the lumbar spine space region based on the non‐linear regression method,thus effectively eliminating the interference caused by the adjacent spine.The 3D Intersection over Union(3D_IOU)is used as the main evaluation indicator for the positioning accuracy.On an open dataset,3D_IOU values of 0.8339�0.0990 and 0.8559�0.0332 in the first and second stages,respectively is achieved.In addition,the average time required for the proposed method in the two stages is 0.3274 and 0.2105 s respectively.Therefore,the proposed method performs very well in terms of both pre-cision and speed and can effectively improve the accuracy of lumbar image segmentation and the effect of surgical path planning.
文摘BACKGROUND Scoliosis is a complex three-dimensional deformity of spine and one of the common complications of collagen VI-related myopathy,caused by mutations in collagen type VI alpha 1 chain(COL6A1),COL6A2,and COL6A3 genes.The typical clinical presentations of collagen VI-related myopathy include weakness,hypotonia,laxity of distal joints,contractures of proximal joints,and skeletal deformities.CASE SUMMARY A 28-year-old female presented with scoliosis for 28 years without weakness,hypotonia,laxity of distal joints,and contracture of proximal joints.Computed tomography and magnetic resonance imaging revealed hemivertebra,butterfly vertebra,and the missing vertebral space.Patients underwent orthopedic surgery and paravertebral muscle biopsy.The Cobb angle dropped from 103.4°to 52.9°.However,the muscle biopsy showed neurogenic muscular atrophy with myogenic lesions,suggesting congenital muscular dystrophy.Gene analysis indicated that mutations in COL6A1(c.1612-10G>A)and COL6A2(c.115+10G>T,c.2749G>A).Immunohistochemistry staining for collagen VI displayed shallow and discontinuous.Eventually,the patient was diagnosed as collagen VI-related myopathy.CONCLUSION This newly found subtype of collagen VI-related myopathy has no typical manifestations;however,it is characterized by severe scoliosis and congenital vertebral deformity.
基金funded by the National Key Research and Development Program of China(No.2018YFE0104200)National Natural Science Foundation of China(51875310,52175274,82172065)Peking University Medicine Sailing Program for Young Scholars’Scientific&Technological Innovation(BMU2023YFJHPY015).
文摘Reconstruction of subarticular bone defects is an intractable challenge in orthopedics.The simultaneous repair of cancellous defects,fractures,and cartilage damage is an ideal surgical outcome.3D printed porous anatomical WE43(magnesium with 4 wt%yttrium and 3 wt%rare earths)scaffolds have many advantages for repairing such bone defects,including good biocompatibility,appropriate mechanical strength,customizable shape and structure,and biodegradability.In a previous investigation,we successfully enhanced the corrosion resistance of WE43 samples via high temperature oxidation(HTO).In the present study,we explored the feasibility and effectiveness of HTO-treated 3D printed porous anatomical WE43 scaffolds for repairing the cancellous bone defects accompanied by split fractures via in vitro and in vivo experiments.After HTO treatment,a dense oxidation layer mainly composed of Y2O3 and Nd2O3 formed on the surface of scaffolds.In addition,the majority of the grains were equiaxed,with an average grain size of 7.4μm.Cell and rabbit experiments confirmed the non-cytotoxicity and biocompatibility of the HTO-treated WE43 scaffolds.After the implantation of scaffolds inside bone defects,their porous structures could be maintained for more than 12 weeks without penetration and for more than 6 weeks with penetration.During the postoperative follow-up period for up to 48 weeks,radiographic examinations and histological analysis revealed that abundant bone gradually regenerated along with scaffold degradation,and stable osseointegration formed between new bone and scaffold residues.MRI images further demonstrated no evidence of any obvious damage to the cartilage,ligaments,or menisci,confirming the absence of traumatic osteoarthritis.Moreover,finite element analysis and biomechanical tests further verified that the scaffolds was conducive to a uniform mechanical distribution.In conclusion,applying the HTO-treated 3D printed porous anatomical WE43 scaffolds exhibited favorable repairing effects for subarticular cancellous bone defects,possessing great potential for clinical application.
文摘Background Icafiine is a flavonoid isolated from a traditional Chinese medicine Epimedium pubescens and is the main active compound of it. Recently, Epimedium pubescens was found to have a therapeutic effect on osteoporosis. But the mechanism is unclear. The aim of the study was to research the effect of Icariine on the proliferation and differentiation of human osteoblasts. Methods Human osteoblasts were obtained by inducing human marrow mesenchymal stem cells （hMSCs） directionally and were cultured in the presence of vadous concentrations of Icariine. 3-（4,5-dimethylthiazol-2-yl）-2,5- diphenyltetrazolium bromide （MTT） test was used to observe the effect of Icariine on cell proliferation. The activity of alkaline phosphatase （ALP） and the amount of calcified nodules were assayed to observe the effect on cell differentiation. The expression of bone morphogenetic protein 2 （BMP-2） mRNA was detected by reverse transcriptase-polymerase chain reaction （RT-PCR）. Results Icadine （20 μg/ml） increased significantly the proliferation of human osteoblasts. And, IcarUne （10 μg/ml and 20 μg/ml） increased the activity of ALP and the amount of calcified nodules of human osteoblasts significantly （P〈0.05）. BMP-2 mRNA synthesis was elevated significantly in response to Icariine （20 μg/ml）. Conclusions Icadine has a direct stimulatory effect on the proliferation and differentiation of cultured human osteoblast cells in vitro, which may be mediated by increasing production of BMP-2 in osteoblasts.
文摘Background There has been an increasing recognition of the importance of sagittal spinopelvic alignment in patients with scoliosis as it relates to clinical outcomes. However, the changes seen in sagittal spinopelvic alignment in adult idiopathic scoliosis patients is poorly defined. This study was conducted to evaluate the sagittal alignment of pelvis and spine in adult idiopathic scoliosis patients.Methods The sagittal parameters of the spine and pelvis were analyzed in lateral standing radiographs of 124 patients （mean age 47.4 years） with adult idiopathic scoliosis, including thoracic kyphosis （TK）, thoracolumbar junction kyphosis （TLJ）, lumbar lordosis （LL）, pelvic incidence （PI）, sacrum slope （SS）, pelvic tilt （PT） and C7 plumb line （C7PL）. The patients were divided into three groups according to the age： 20-40 years, 41-64 years, and ≥65 years. The parameters were compared with those in normal adults and adolescent idiopathic scoliosis （AIS） patients. The relationship between all parameters as well as age and sagittal parameters were analyzed.Results The PI in patients with adult idiopathic scoliosis was 58.1°±13.0°, which was significantly higher than that in normal adults. The PT （19.9°±10.6°） was also higher than that in both normal adults and AIS patients, while the SS （38.1°±12.0°） was similar or smaller. As age increased, C7PL, PT and TJL increased while LL decreased. There was no relationship between age and both PI and TK. PT had the strongest statistical association with the C7PL.Conclusions PI is higher in adult idiopathic scoliosis than normal subjects. The PT is the most relevant pelvic parameter to the global sagittal alignment of the spine. Age significantly influences sagittal parameters of the spine and pelvis except the PI and TK.
基金supported by a grant from the Major Programs of Peking University Third Hospital(No.Y77491-06)。
文摘Background:Finding an optimal treatment strategy for adolescent idiopathic scoliosis(AIS)patients remains challenging because of its intrinsic complexity.For mild to moderate scoliosis patients with lower skeletal growth potential(Risser 3-5),most clinicians agree with observation treatment;however,the curve progression that occurs during puberty,the adolescent period,and even in adulthood,remains a challenging issue for clinicians.The aim of the study is to investigate the efficacy of Schroth exercise in AIS patients with lower skeletal growth potential(Risser 3-5)and moderate scoliosis(Cobb angle 20°-40°).Methods:From 2015 to 2017,data of 64 patients diagnosed with AIS in Peking University Third Hospital were reviewed.Forty-three patients underwent Schroth exercise were classified as Schroth group,and 21 patients underwent observation were classified as observation group.Outcomes were measured by health-related quality of life(HRQOL)and radiographic parameters.HRQOL was assessed using the visual analog scale(VAS)scores for back,Scoliosis Research Society-22(SRS-22)patient questionnaire.Radiographic spinopelvic parameters were obtained from anteroposterior and lateral X-rays.The pre-treatment and post-treatment HRQOL and radiographic parameters were tested to validate Schroth exercise efficacy.The inter-rater reliability of the radiographic parameters was tested using the interclass correlation coefficient(ICC).The pairedt test was used to examine HRQOL and radiographic parameters.Clinical relevance between C2-C7 sagittal vertical axis(SVA)and thoracic kyphosis was analyzed using Spearman correlation.Results:In Schroth group,VAS back score,SRS-22 pain,and SRS-22 self-image domain were significantly improved from pre-treatment 3.0±0.8,3.6±0.5,and 3.5±0.7 to post-treatment 1.6±0.6(t=5.578,P=0.013),4.0±0.3(t=-3.918,P=0.001),and 3.7±0.4(t=-6.468,P<0.001),respectively.No significant improvements of SRS-22 function domain(t=-2.825,P=0.088)and mental health domain(t=-3.174,P=0.061)were observed.The mean Cobb angle decreased from 28.9±5.5°to 26.3±5.2°at the final follow-up,despite no statistical significance was observed(t=1.853,P=0.102).The mean C2-C7 SVA value decreased from 21.7±8.4 mm to 17.0±8.0 mm(t=-1.224P=0.049)and mean T1 tilt decreased from 4.9±4.2°to 3.5±3.1°(t=2.913,P=0.011).No significant improvement of radiographic parameters and HRQOL were observed in observation group.Conclusions:For AIS patients with a Risser 3-5 and a Cobb angle 20°-40°,Schroth exercises improved HRQOL and halted curve progression during the follow-up period.Both cervical spine alignment and shoulder balance were also significantly improved after Schroth exercises.We recommend Schroth exercises for patients with AIS.
文摘Background： Total knee arthroplasty （TKA） is the most frequently performed procedure in treating advanced knee osteoarthritis. Excessive perioperative blood loss can sometimes lead to postoperative anemia. Tranexamic acid （TXA） is a potent fibrinolysis inhibitor which has been extensively used at the surgical incision and closure to lower overall blood loss in adult reconstruction surgery. Our previous study suggested that about two-thirds of the total blood loss （TBL） came from hidden blood loss （HBL） on postoperative days 1 and 2. The role of reducing HBL with TXA administration in postoperative TKA patients is unknown. The current study was designed to evaluate the efficiency and safety of supplemental intravenous （IV） TXA in further redticing HBL after primary TKA. Methods： A prospective pilot study was conducted at a single institution on 43 consecutive patients who underwent unilateral TKA from September 2014 to February 2015. All patients were given 1 g of IV TXA 10-15 rain before operation and another 1 g of IV TXA at the time of wound closure on the day of surgery. On postoperative days 1 and 2, the supplemental group （n = 21） was given additional 1 g of TXA intravenously twice a day, whereas the control group （n = 22） received an equal volume of saline. Drain output, hemoglobin （Hb）, and hematocrit （HCT） were recorded preoperatively and 5 consecutive days postoperatively in both groups. HBL was calculated with the Gross formula. Pre- and post-operative lower extremity Doppler venous ultrasound was performed in all patients to detect deep vein thrombosis （DVT）. The indexes were compared using the Mann-Whitney test, whereas the results of Hb and HCT were analyzed by repeated-measures analysis of variance. The difference was considered statistically significant ifP 〈 0.05. Results： The demographics and surgical characteristics of the two groups were comparable. Supplemental group had higher Hb level on postoperative days 1-5 compared to the control; however, the difference was not significant （F = 2.732, P = 0.106）. The HCT of the supplemental group was significantly higher than that of the control group on postoperative day 5 （F= 5.254, P = 0.027）. No significant difference was found in drainage volume and TBL, but the HBL was reduced in the supplemental group （supplemental 133.1 [71.8,287.3] ml and control 296.0 [ 185.3, 421.4] ml, Z = 2.478, P = 0.013. median [interquartile range]）. There was one DVT in the control group and none in the supplemental group. All patients were tbllowed at 1 year after surgery, and no further complications were reported. Conclusion： Based on the current study, additional doses of IV TXA could potentially further reduce HBL alter primary TKA without increasing the risk of venous thromboembolism.
文摘Background This study investigated the relationship between the height of osteotomy and the correction of the kyphotic angle during posterior closing wedge osteotmy with instrumentation and the spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach in thoracolumbar kyphosis, and using this relationship as the basis of the preoperative design. Methods From April 1996 to June 2007, 30 thoracolumbar kyphosis patients with complete medical records and clear X-ray photograms have undergone operation. Of these 30 cases, 16 cases underwent posterior closing wedge osteotmy with instrumentation while the height of the osteotomy and the correction of the angle have been measured; 14 cases underwent spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach while the height of the osteotomy, the height and the place of the cage and the correction of the angle were also measured. A simple geometrical model was simulated to calculate the relationship between the height of the oeteotomy and the correction of the angle and these results are finally compared with the data coming from the actual measuring by the Wilcoxon statistic method. Results The distribution of data from the 16 cases by posterior closing wedge osteotomy with instrumentation was as such： 9 male and 7 female, the mean age was 49.2 years （range 38--70）, the kyphosis improved from an average of 30° （range 15°--45°） preoperatively to 4° （range -26°--30°） postoperatively, the kyphosis was corrected on average 2.5-0 per 1 mm in the height of the osteotomy. The results from the simple geometrical model were that the mean of the correction of the angle per 1 mm was 2.2°. As a result, there was no significant difference （P 〉0.05） when comparing the measurement collected with the result simulated from the geometric model. The distribution of data from the 14 cases by spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach was as such： 5 male and 9 female, the mean age was 35.3 years old （range 15--57）, the kyphosis improved from an average of 64°- （range 34°--95°） preoperatively to 8.70 （range -10°--22°） postoperatively. The kyphosis was corrected on average of 6.2°- per 1 mm in the height of the psteotomy. The results from the simple geometrical model is that the mean of the correction of the angle per 1 mm was 6.6°. There was also no significant difference （P 〉0.05） when comparing the measurement collected with the result simulated from the geometric model. Conclusions The therapeutic effect is significant for both posterior closing wedge osteotomy with instrumentation and spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach. The posterior closing wedge osteotomy with instrumentation is an easier approach with the mean angle of the correction per 1 mm of 2.5°- and the maximum angle of correction of 45°. The spinal osteotomy with cage inserting into the intervertebral gap and closing posteriorly by a single posterior approach is more efficient with the mean angle of correction per I mm of 6.2°. It should be reserved for the severe cases of thoracolumbar kyphosis. We can also use the formula to held us constructing Preoperative desiqn.
文摘Background Chordomas of the upper cervical spine are rare and present unique surgical challenge.This study aimed to describe the clinical characteristics and surgical management of patients with chordomas of the upper cervical spine.Methods Twenty-one patients with chordomas of the upper cervical spine who were treated in Peking University Third Hospital from January 1999 to October 2012 were retrospectively analyzed.Survival was calculated by the Kaplan-Meier method and was compared between groups using the log-rank test.Results The postoperative diagnosis was classical chordoma in 20 cases and chondroid chordoma in one case.The mean operative time was 9.5 hours （range 6-17 hours）,and the mean blood loss was 2 812 ml （range 700-4 800 ml）.There were two postoperative deaths.Unilateral vertebral artery ligation was performed in six patients,cervical nerve roots were cut in six patients,and the external branch of the superior laryngeal nerve was repaired after being cut in one case.Two patients developed postoperative velopharyngeal incompetence,and loosening of the occipitocervical screws was observed in one patient.The recurrence rate was 66.7% （10/15） after a mean follow-up period of 46.8 months （range 14-150 months）.The 5-and 10-year overall survival rates were （39.8±13.1）% and （31.9±12.7）%,respectively.There was a significant difference in survival rate between patients who underwent surgery and those who did not.Conclusion In spite of the high rates of recurrence and complications after surgical treatment of chordomas of the upper cervical spine,intralesional resection combined with adjuvant radiotherapy remains the optimal treatment to prolong survival.
文摘Background Accurate knowledge of the spinal structural functions is critical to understand the biomechanical factors that affect spinal pathology. Many studies have investigated the human vertebral motion both in vitro and in vivo. However, determination of in vivo motion of the vertebrae under physiologic loading conditions remains a challenge in biomedical engineering because of the limitations of current technology and the complicated anatomy of the spine. Methods For in vitro validation, a human lumbar specimen was imbedded with steel beads and moved to a known distance by an universal testing machine （UTM）.
文摘Background： Giant cell tumors （GCTs） are benign, locally aggressive tumors. We exalnined the rate of local rectirrence of spinal GCTs and sought to identify recurrence factors in patients who underwent surgery. Methods： Between 1995 and 2014, 94 mobile spine GCT patients were treated at our hospital, comprising 43 male and 51 female patients with an average age of 33.4 years. Piecemeal intralesional spondylectomy and total en bloc spondylectomy （TES） were performed. Radiotherapy was suggested for recurrent or residual GCT cases. Since denosumab was not available before 2014 in our country, only interferon and/or zoledronic acid was suggested. Results： Of the 94 patients, four underwent conservative treatment and 90 underwent operations. Seventy-five patients （79.8%） were followed tip for a minimum of 24 months or until death. The median follow-up duration was 75.3 months. The overall recurrence rate was 37.3%. Ten patients （13.3%） died before the last follow-up （rnedian： 18.5 months）. Two patients （2.6%） developed osteogenic sarcoma. The local recurrence rate was 80.0% （24/30） in patients who underwent intralesional curettage, 8.8% （3/34） in patients who underwent extracapsular piecemeal spondylectomy,and 0 （0/9） in patients who underwent TES. The risk factors for local recurrence were lesions located in the cervical spine （P = 0.049）, intralesional curettage （P 〈 0.001 ）, repeated surgeries （P 0.014）, and malignancy （P 〈 0.001 ）. Malignant transformation was a significant risk factor for death （P 〈 0.001 ）. Conclusions： Cervical spinal tumors, curettage, and nonintact tumors were risk l;actors for local recurrence. Intralesional curettage and malignancy were the most important significant factors for local rectirrence and death, respectively.
文摘Background This retrospective study aimed to investigate the difference of the intra-dural reserving space for spinal cord in magnetic resonance imaging （MRI） between patients with and without developmental cervical stenosis and its clinical significance.Methods A total of 264 patients with cervical spondylotic myelopathy who had decompression surgeries were recruited.The average follow-up was 29 months.Based on their lateral radiographs,they were divided into stenosis group and non-stenosis group.On the magnetic resonance images,the ratio of the sagittal diameter of the dural sac to that of the vertebral body was measured and calculated as MRI Pavlov ratio at the mid-vertebral level on T2-weighted sagittal images from C3 to C7.The ratio of the transverse area of the spinal cord to that of the dural sac was measured and calculated as occupation ratio on T2-weighted axial images at the same levels.The MRI Pavlov ratio and occupation ratio were compared between the two groups.The stenosis group was further divided into space-reserving and non-space-reserving subgroups based on the occupation ratios; then clinical parameters were compared between the two subgroups to determine the clinical significance of the reserving space.Results The MRI Pavlov ratio of the stenosis group was significantly smaller than that of the non-stenosis group at C3-C7 （P ＜0.01）,while the occupation ratio was significantly larger only at C7 （P ＜0.05）.For the space-reserving subgroup,the postoperative recovery rate was lower （P ＜0.05）.The postoperative recovery rate was （23±6）％ in anterior approach,larger than （-23±15）％ in posterior approach （P ＜0.05）.Conclusions Developmental cervical stenosis is associated with a smaller sagittal diameter of the dural sac,but does not lead to a significant decrease in intra-dural space available for the cord.For patients with normal intra-dural space,the recovery after anterior decompression surgery was better than posterior approach.
基金This research was supported by grants from the National Natural Science Foundation of China （No. 81472041） and the Beijing Municipal Science and Technology Commission （No. Z141107002514011）.
文摘Background The treatment strategies for multilevel thoracic ossification of the posterior longitudinal ligaments （T-OPLL） were rarely reported. The aim of this study was to investigate the clinical outcomes and complications of circumferential decompression for multilevel T-OPLL and compare two different methods in the management of the OPLL （resection or floating）. Methods Data of sequentially treated patients who received surgical treatment for thoracic spinal stenosis caused by multilevel T-OPLL from January 2005 to February 2012 were retrospectively reviewed. Based on the surgical approaches applied, the patients were divided into two groups. Group A consisted the patients who received posterior decompression and group B consisted the patients who received circumferential decompression via the posterior approach. Group B was further divided into two subgroups： subgroup 1 （the resection group） where the OPLL was completely resected and subgroup 2 （the floating group） where the OPLL was floated. Results A total of 49 patients were included in the study. Fourteen patients with single posterior decompression were included in group A and 35 patients who received circumferential decompression were included in group B. In group B, 29 patients had complete resection of the ossified posterior longitudinal ligaments, while the other six underwent a flotation procedure. The follow-up data were available in 39 patients. Mean JOA scores improved from 5.4 ± 1.8 to 7.5 ± 2.8 in group A and from 3.7 ± 1.8 to 7.9 ± 2.4 in group B. The main complications included cerebrospinal fluid （CSF） leakage and postoperative neurelogic deterioration （ND）. Twenty-three of the 25 cases with postoperative CSF leakage achieved a complete recovery at the last follow-up and 12 of the 15 cases with ND achieved some neurological improvement at the last follow-up. Conclusions Circumferential decompression via the posterior approach is an effective surgical method for thoracic spinal stenosis caused by multilevel OPLL of the thoracic spine. Patients who receive complete resection of the ossified posterior longitudinal ligaments may have better recovery rate than the ＂floating＂ group.
文摘Diffuse-type tenosynovial giant cell tumor （D-TGCT） belongs to a group of lesions believed to arise from tendon sheaths,bursae,or the synovium of diarthrodial joints.The etiology of D-TGCT is unknown.Because it shares histological characteristics with pigmented villonodular synovitis,however,D-TGCT is also termed extra-articular pigmented villonodular synovitis.D-TGCT,which occurs mainly in middle-aged women （20-50 years of age1）,usually involves large load-bearing joints （e.g.,knee,ankle,and hip）.Clinical case reports of D-TGCT involving the spine are rare.2 We retrospectively analyzed a series of three patients diagnosed with cervical D-TGCT in our department over a 10-year period.
文摘Background Differentiated thyroid cancer （DTC） is a common primary cancer for spinal metastases （SM）.The treatments for DTC spinal metastases （SM） have evolved from simple surgery and radiotherapy to a multidisciplinary comprehensive therapeutic strategy of combined spinal surgery,general surgery,radiotherapy,nuclear medicine and endocrinology.The purpose of this study was to discuss the efficacy and prognosis associated with different surgical treatments of SM patients with DTC.Methods A total of 21 consecutive patients with SM of DTC that were treated between 1999 and 2013 were studied.Biopsy was routinely performed to achieve the pathological diagnosis before treatment.Three patients underwent total spondylectomy intralesionally or piecemeally,and 18 had curettage.Postoperative recurrence and survival times were analyzed by the Kaplan-Meier methods.Results Nineteen patients （90％） had an average of 42.7 months （range,7-170 months） follow-up.The median visual analogue scale for pain reduced from 5 points to 1 point （P ＜0.01）,and the median Karnofsky performance score increased from 70 to 90 points after surgery （P ＜0.01）.Seventeen patients with neurological deficits attained improvements after surgeries,of at least one level according to the Frankel classification （P ＜0.01）.Eight patients with curettage had recurrence.Four patients died of DTC,12 patients lived with disease,and three patients were disease-free.No significant effects on postoperative recurrence or survival were observed between surgery combined with conservative treatment,total spondylectomy,the number of bone metastases and visceral metastasis.Conclusions DTC-SM have a relatively favorable prognosis,and curettage and stabilization can effectively relieve the pain and improve the quality of life and neurological status of the patients.For patients with Tomita scores of ＜3,total spondylectomy may have better clinical outcomes.Comprehensive therapeutic strategies including surgery,radioiodine,external beam radiation therapy and embolization should be considered for most patients.
