ABSTRACT
OBJECTIVE:Cement-augmentation pedicle screws have been widely used in spinal internal fixation surgery combined with osteoporosis in recent years,which can significantly improve the fixation strength,but compared with conventional methods,whether it has more advantages is still inconclusive of evidence-based medicine.To systematically evaluate the efficacy and safety of cement-augmented pedicle screw in the treatment of thoracolumbar degenerative diseases with osteoporosis. METHODS:Clinical controlled trials concerning the cement-augmented pedicle screw and the traditional pedicle screw placement for thoracolumbar degenerative diseases with osteoporosis were retrieved from the electronic databases such as CNKI,CBM,WanFang,VIP,PubMed,Cochrane Library,Web of Science and Embase.According to the unified criteria,we performed literature screening and quality evaluation.The meta-analysis was performed using RevMan 5.4 software. RESULTS:(1)Totally 20 articles were selected eventually,involving 2 randomized controlled studies and 18 retrospective cohort studies,totally 1 566 patients.Among them,789 cases were in the cement-augmented screw group and 777 cases in the conventional screw group.(2)Meta-analysis results showed that Japanese Orthopaedic Association score,intervertebral space height and fusion rate were higher in the cement-augmented screw group than those in the conventional screw group(MD=1.60,95%CI:1.14,2.07,P<0.000 01;MD=1.26,95%CI:0.62,1.90,P=0.000 1;OR=11.24,95%CI:2.86,44.14,P=0.000 5).Operation time was longer in the cement-augmented screw group than that in the conventional screw group(SMD=0.82,95%CI:0.42,1.23,P<0.000 1).Postoperative visual analog scale score,Oswestry dysfunction index score and incidence of screw loosening were lower in the cement-augmented screw group than those in the conventional screw group(MD=-0.50,95%CI:-0.78,-0.21,P=0.000 7;SMD=-0.49,95%CI:-0.88,-0.10,P=0.01;OR=0.08,95%CI:0.05,0.12,P<0.000 01).Hospitalization time,intraoperative blood loss,and postoperative drainage volume were not significantly different between the two groups(P>0.05). CONCLUSION:Compared with conventional pedicle screw placement,cement-augmented pedicle screw is more effective in the treatment of osteoporotic thoracolumbar degenerative disease by improving fusion rate and interbody height,reducing the incidence of screw loosening,and elevating long-term efficacy.
ABSTRACT
BACKGROUND: Osteoporosis and fracture type are two important reasons for the failure of internal fixation of proximal femoral nail antirotation. Type AO31-A3.3 intertrochanteric fracture, because of its involvement in the lateral wall, greatly increased the instability of the fracture. In addition, the elderly are mostly osteoporosis patients, so failure and postoperative complications of internal fixation of proximal femoral nail antirotation in the elderly with type AO31-A3.3 intertrochanteric fracture are higher. OBJECTIVE: To explore the difference of biomechanics between bone cement augmented and common proximal femoral nail antirotation in the treatment of type AO31-A3.3 intertrochanteric fracture. METHODS: CT data of one 75-year-old volunteer with intertrochanteric fracture were selected to import into Mimics 19.0 and Geomagic studio 2017 software to extract and optimize the three-dimensional model of the right femur. SolidWorks 2017 software was used to draw the internal fixation model and assemble it with the femur model according to the standard operation technology. The model was imported into Hypermesh 14.0 software to cut the bone to obtain the type AO31-A3.3 model with common proximal femoral nail antirotation. The cancellous bone around the proximal end of the screw blade was redefined as bone cement, which is the model of bone cement augmented proximal femoral nail antirotation. The material property parameters, boundary conditions and applied loads were set up and stored as K files respectively and imported into LS-DYNA software for solution. RESULTS AND CONCLUSION: (1) Compared with the common proximal femoral nail antirotation, the treatment of the elderly type AO31-A3.3 intertrochanteric fracture with the bone cement augmented proximal femoral nail antirotation has the advantages of lighter cutting degree of the screw blade, smaller varus, rotation angle and displacement of the femoral head and neck bone block, and better biomechanical effect. (2) The complete lateral wall can effectively support the femoral head and neck bone block and resist the skull and neck bone block as the lateral action point of three-point support. The pronation and rotation tendency can effectively prevent the head and neck screws from withdrawing. (3) The strong anchoring force of bone cement can stabilize the screw blade, enhance the internal action point of three-point support, and conduct and disperse the pressure.
ABSTRACT
PURPOSE: The aim of this study was to evaluate and report the new method with a cement augmented screw fixation again to treat the failed intertrochanteric fracture in elderly which were treated with ordinary compression hip screw initially. MATERIALS AND METHODS: From Mar. 1988 to May 2007, 10 patients (mean age 69 years) with the failed intertrochanteric fracture which were treated with initial hip screw, were treated with a cement augmented compression hip screw again. The mean follow-up after surgery was over 18 months. The cause of failure, the period upto the reoperation, the neck-shaft angle after the reoperation, the position of lag screw in the femoral head, and the degree of union at last follow-up were analyzed. The change in the functional hip capacity were evaluated by the classification of Clawson. RESULTS: Causes of failure were superior cutting-out in 6 cases, cortical anchorage failure in 3, and nonunion in one case. The period upto the reoperation was average 7.8 months. Valgus reduction of average 5.7degrees was achieved, and the positions of lag screw were postero-inferior in 6 cases, center in 3, infero-center in one case. We obtained complete union in 9 cases. The functional outcome showed moderate in 6 cases, good in 3 and poor degree in one case. CONCLUSION: Cement augmented compression hip screw treatment will possibly reduce cutting-out of screw and bring more stability in fixation for intertrochanteric fractures in old osteoporotic patients, as well, even in failed cases treated with initial compression hip screw, but proper selection of patients is important.