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Objective To evaluate the biomechanical properties of 3D printed individualized titanium alloy pelvic prosthesis in static and gait states by the method of finite element analysis. Methods Three patients with different types of pelvic tumors were treated by hemi-pelvic arthroplasty with resection of hemi-pelvis. CT and MRI were performed before the surgery, and the corresponding individualized titanium alloy pelvic prostheses were designed. The pelvic models were reconstructed with 3D reconstruction technique, and then assembled with the individualized pelvic prostheses. The human skeletal muscle model was established by AnyBody software to perform gait dynamics analysis. The stress distribution and stress concentration areas of 3 reconstructed pelvic models in static and gait states were obtained by ABAQUS. Results Under both static and gait conditions, the maximum stress of the 3 pelvic prostheses was smaller than the yield strength of the titanium alloy. The pelvic ring of the reconstructed pelvis could meet the rule of stress conduction. The patients’ daily life returned to normal condition after the surgery. Conclusions The effect of 3D prosthetic titanium prosthesis on recovery of pelvic ring is satisfactory, and its effectiveness and stability can meet the requirement of human biomechanics. The analytic results can provide references for clinicians and prosthesis designers.
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Objective To evaluate the biomechanical properties of 3 D printed individualized titanium alloy pelvicprosthesis in static and gait states by the method of finite element analysis.Methods Three patients with different types of pelvic tumors were treated by hemi-pelvic arthroplasty with resection of hemi-pelvis.CT and MRI were performed before the surgery,and the corresponding individualized titanium alloy pelvic prostheses were designed.The pelvic models were reconstructed with 3D reconstruction technique,and then assembled with the individualized pelvic prostheses.The human skeletal muscle model was established by AnyBody software to perform gait dynamics analysis.The stress distribution and stress concentration areas of 3 reconstructed pelvic models in static and gait states were obtained by ABAQUS.Results Under both static and gait conditions,the maximum stress of the 3 pelvic prostheses was smaller than the yield strength of the titanium alloy.The pelvic ring of the reconstructed pelvis could meet the rule of stress conduction.The patients' daily life returned to normal condition after the surgery.Conclusions The effect of 3D prosthetic titanium prosthesis on recovery of pelvic ring is satisfactory,and its effectiveness and stability can meet the requirement of human biomechanics.The analytic results can provide references for clinicians and prosthesis designers.
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<p><b>BACKGROUND</b>Mortality rates for patients with gas gangrene from trauma or surgery are as high as 25%, but they increase to 50%-80% for patients injured in natural hazards. Early diagnosis and treatment are essential for these patients.</p><p><b>METHODS</b>We retrospectively analyzed the clinical characteristics and therapeutic results of 19 patients with gas gangrene of the limbs, who were injured in the May 2008 earthquake in the Wenchuan district of China's Sichuan province and treated in our hospital, to seek how to best diagnose and treat earthquake-induced gas gangrene.</p><p><b>RESULTS</b>Of 226 patients with limbs open injuries sustained during the earthquake, 53 patients underwent smear analysis of wound exudates and gas gangrene was diagnosed in 19 patients. The average elapsed time from injury to arrival at the hospital was 72 hours, from injury to definitive diagnosis was 4.3 days, and from diagnosis to conversion of negative findings on wound smear analysis to positive findings was 12.7 days. Anaerobic cultures were also obtained before wound closure. The average elapsed time from completion of surgery to recovery of normal vital signs was 6.3 days. Of the 19 patients, 16 were treated with open amputation, two with closed amputation, and 1 with successful limb salvage; 18 patients were successfully treated and one died.</p><p><b>CONCLUSIONS</b>In earthquakes, rapid, accurate screening and isolation are essential to successful treatment of gas gangrene and helpful in preventing nosocomial diffusion. Early and thorough debridement, open amputation, and active supportive treatment can produce satisfactory therapeutic results.</p>
Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , Child , Female , Humans , Male , Middle Aged , Young Adult , Earthquakes , Extremities , Pathology , General Surgery , Gas Gangrene , Diagnosis , General Surgery , Retrospective StudiesABSTRACT
<p><b>OBJECTIVE</b>To determine the operation procedure of total hip arthroplasty (THA) for Crowe type-IV developmental dysplasia of hip and its relationship with nerve injury.</p><p><b>METHODS</b>A consecutive series of 39 THAs was performed for Crowe type-IV developmental dysplasia of hip in 35 patients (all female). The mean age of the patients at the time of surgery was 46 years (range 36 - 56 years). Thirty-five hips in 31 patients were followed up. The average follow-up period of the whole series was 4 years (range 1 - 8 years). All procedures were carried out through a lateral-posterior approach. In 33 of 35 hips, the cup was inserted in the "true" acetabulum. All the prostheses used were cementless, except for 5 cemented femoral stems in 5 patients. Each patient was evaluated clinically and by radiographs before the operation and during the follow-up period, according to the Harris hip score (HHS).</p><p><b>RESULTS</b>None of the cups and stems were revised for aseptic loosening, dislocation or infection during the follow-up period. The mean preoperative HHS was 43 compared with the postoperative HHS of 87. The mean amount of postoperative leg lengthening was 5 cm (range 4 - 6 cm).</p><p><b>CONCLUSIONS</b>The reconstruction of the hip at the level of the "true" acetabulum through a lateral-posterior approach is a safe and effective procedure of THA for Crowe type-IV developmental dysplasia of hip in adults. Acute leg lengthening of less than 6 cm could not cause nerve injury.</p>
Subject(s)
Adult , Female , Humans , Middle Aged , Arthroplasty, Replacement, Hip , Methods , Follow-Up Studies , Hip Dislocation, Congenital , General Surgery , Treatment OutcomeABSTRACT
Objective To observe the effects of the Ossatron high-energy shock waves on bone nonunion and delayed union.Methods Between October 2004 and October 2005,18 patients with nonunion and four patients with delayed union were treated with high-energy extracorporeal shock wave therapy(Ossatron,HMT Co., Swiss).Facture lines were located with C-arm X-ray before treatment.Parameters of shock waves were decided according to fracture sites.Patients with unstable fixation received plaster or bracing for 6 to 8 weeks after treatment. After therapy,follow-up radiography was performed at 6 and 12 weeks and monthly afterwards until the fracture united. Results The mean follow-up was 6.7 months(range,3 to 12 months).There were no complications except local petechial hemorrhage and local swelling in 10 patients.Thirteen patients(59.1%)got bony union,including 12 patients(66.7% )with stable internal fixation,and the average healing time was 4.3 months(range,6 weeks to 6 months).Nine fractures(40.9%)still suffered nonunion.Conclusion High-energy shock waves are a good alternative therapy for nonunion and delayed union,with obvious advantages of being non-invasive and safe.
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Objective To investigate the ostengenie potential of adipose-derived stem cells(AD- SCs)when exposed to adenovirns containing hBMP-2 cDNA(Adv-hBMP-2)and offer a choice of cell source for gene therapy and tissue engineering.Methods Human adipose tissues were obtained from patients who received orthopaedic surgery or liposuction.ADSCs were obtained by digesting the adipose tissues.Firstly,flowcytometric analysis was performed for the confirmation of mesenchymal stem cell ori- gin and the surface markers including CD34,CD44,CD68,CD71,CD90,and CD105.The ADSCs were transfected by Adv-hBMP-2 and the effects were tested in vitro,lmmunoprecipitation and Western blotting and ELISA were performed for confirming BMP gone transduction and its stable expression.The transform of ADSCs was assessed by extracellular ALP staining,intracellular ALP spectrophotometry,von Kossa staining and RT-PCR.In the in vivo experiment ADSC-Adv-hBMP-2 cells were injected into the hind limb of nude mice and analyzed radiographically and histologically.Results ADSCs were successfully isolated from human adipose tissues.The isolated ADSCs expressed CD44,CD71,CD90 and CD105 and CD34 and CD68 were absent.The result confirmed the mesenchymal stem cell origin of the cells.West- ern blotting and ELISA confirmed successful and persistent hBMP-2 production by ADSC-Adv-hBMP-2 cells.Extracellular ALP staining,intracellular ALP spectrophotometry,yon Kossa staining and RT-PCR revealed that ADSCs treated with Adv-hBMP-2 had a tendency of transfering into osteoblast.X-ray and H&E sections from hind limb of nude mice injected with ADSC-Adv-hBMP-2 cells confirmed bone forma- tion at 2 weeks.Conclusions Liposuction aspirates contain abundant ADSCs that can be transduced with hBMP-2 gene,and the tranduced ADSCs differentiate into the osteoblast.ADSCs may be an ideal source of mesenchyme-lineage stem cells for gone therapy and tissue engineering.