RESUMO
Background: The specific aim of this study was to evaluate the mechanical properties of cement prepared with the advanced one-step mixing system and whether the addition of vacuum conditions yielded an appreciable improvement in the biomechanical strength or overall quality of bone cement. Methods: The advanced one-step mixing system was used. Twelve specimens were prepared by mixing under vacuum conditions and 12 specimens were prepared by mixing without a vacuum. Radiographs of cement specimens were analyzed to determine the porosity of the test region. Tensile testing of the specimens was performed with a loading rate of 2.54mm/min at room temperature. The ultimate tensile strength (UTS) and the tensile elastic modulus (E) were determined for each sample. Results: The UTS of the bone cement samples mixed under vacuum conditions were not significantly different than those mixed without vacuum (vacuum: 39±6MPa; non-vacuum: 35±6MPa; p=0.637). The E of samples mixed under vacuum conditions was significantly higher than the bone cement mixed without vacuum (vacuum: 2.78±0.06GPa; non-vacuum: 2.63±0.15GPa; p=0.019). Radiographic images showed samples mixed under vacuum conditions contained fewer defects than the samples mixed without vacuum (vacuum: 3.5%±3.3% (range: 0.0%-9.0%); non-vacuum: 6.9%±1.0% (range: 4.6%-8.2%)). Conclusion: Mixing bone cement with the advanced one-step mixing system under vacuum conditions does not produce an appreciable difference in the UTS of the bone cement in a bench biomechanical testing model compared to the bone cement mixed without vacuum. It does, however, create a less porous cement mixture with a higher E compared to cement mixed without vacuum. Level of Evidence: V.
Assuntos
Cimentos Ósseos , Teste de Materiais , Resistência à Tração , Vácuo , Polimetil Metacrilato/química , Humanos , Módulo de Elasticidade , Fenômenos Biomecânicos , PorosidadeRESUMO
Introduction: The specific aim of this retrospective study was to determine whether bone quality has any effect on the complication rates or overall survivorship between helical blades and lag screws in cephalomedullary nails used for intertrochanteric hip fractures. Methods: The authors reviewed clinical charts and radiographic studies of patients between January 2012 and August 2019. We reviewed radiographic images (pre-, intra-, and post-operative) to evaluate fracture fixation type, fracture reduction grade, and post-operative complications. We collected dual energy x-ray absorptiometry scan results (T-score) and serum alkaline phosphatase (ALP) isoenzyme activity values to evaluate patient bone quality. Results: We included 303 cases (helical: 197, screw: 106) in the study. Complications were found in 31 (16%) helical blade cases and 23 (22%) lag screw cases. No statistically significant difference was detected when comparing complication rates with patient bone quality between the two groups. These two groups had similar one-year implant survivorship with respect to T-score, the low ALP level group, and normal ALP level group. The helical blade had higher implant survivorship compared to lag screw in five-year survival rate with respect to osteoporotic group, high ALP level group, and normal ALP level group (osteoporotic: 77% vs 69%, high ALP: 73% vs 67%, normal ALP: 70% vs 64%). Conclusions: Similar complication rates were observed between helical blade and lag screw constructs in cephalomedullary femoral nails when accounting for patient bone quality. However, the helical blade design had a higher five-year survival rate.
RESUMO
BACKGROUND: The opioid epidemic in the United States continues to be problematic as morbidity and mortality rates increase yearly. Orthopaedic surgeons are the third highest prescribing group among physicians. Studies show that orthopaedic surgeons tend to overprescribe opioids, but published data on patient opioid utilization, pain management satisfaction, and national clinical practice guidelines on opioid prescribing are scarce or lacking. Furthermore, little information is available on influences on physician prescribing behavior and whether changes in prescribing habits are lasting. METHODS: Using recently published opioid utilization and prescribing guidelines for hand surgery, we created an opioid prescribing quality improvement program with the aim of reducing postoperative opioid prescribing without negatively impacting patient pain satisfaction. The main aspect of the program was the implementation and modification of an opioid prescribing order set, but the program also included surgeon education-executed in 2 intervention steps-about how their prescribing behavior compared with that of their peers. Three phases of data representing 3 months each were collected prior to, between, and after the interventions. RESULTS: Two thousand and sixty-seven hand surgery cases were reviewed (629 in Phase 1, 655 in Phase 2, and 783 in Phase 3). The average number of morphine milligram equivalents (MMEs) was reduced from 142.0 in Phase 1 to 69.9 in Phase 2 (51% reduction) to 61.3 in Phase 3 (57% reduction compared with Phase 1). Significant reductions in MMEs occurred across the procedural categories as well as the hand surgeons. Patient pain satisfaction was similar before and after implementation of the first intervention (p = 0.96). CONCLUSIONS: Quality improvement methods were effective in altering prescribing behavior by physicians in the long term, and our approach may be effective if applied more widely. Similar studies on quality improvement methods and prescribing behavior, patient opioid utilization, and patient satisfaction with pain management are needed in other orthopaedic subspecialties. CLINICAL RELEVANCE: Evidence-based guidelines, a quality improvement process, and unblinded information on prescribing behavior compared with that of peers may result in long-lasting reductions in surgeons' opioid prescribing practices.