The Hip Center Rule Can be Used to Decide if Measured Pelvic Incidence is Accurate

STUDY DESIGN: Simulation study. OBJECTIVE: Pelvic incidence (PI) should be considered during surgical planning. The ideal patient position with both hip centers perfectly aligned for a lateral radiograph is rarely obtained. It has been suggested that a radiograph with axial and coronal rotation up to 20° is acceptable to obtain a measured PI within 6 degrees of the actual PI. We seek to: (1) evaluate the effect of variations in PI and patient malpositioning on measured vs true PI, and (2) determine whether the presence of one hip center within the bony acetabular rim of the contralateral hip can serve as a simple clinical decision rule on the accuracy of measured PI. METHODS: Published anthropometric three-dimensional pelvic landmark coordinates were used in this study. Radiographic projections were generated using linear algebra for combinations of axial and coronal rotation from -20° to +20°. True and measured PIs were compared. RESULTS: Rotation to 20° cannot be uniformly accepted as decision rule. Pelvises with higher PIs are more sensitive to malpositioning with greater PI deviation with smaller amounts of rotation. Diagnostic performance of the hip center rule demonstrated a sensitivity of 25.58% and a specificity of 100.00%. CONCLUSIONS: Rather than assessing the quality of radiographs for PI measurement by magnitude of malpositioning, we recommend clinicians use the hip center rule. As long as at least one hip center is contained within the bony acetabular rim of the contralateral hip, there is high confidence that measured PI will be within 6° of true PI

Insulin-Like Growth Factor-1 Receptor Signaling Increases the Invasive Potential of Human Epidermal Growth Factor Receptor 2-Overexpressing Breast Cancer Cells via Src-Focal Adhesion Kinase and Forkhead Box Protein M1 s

ABSTRACT Resistance to the human epidermal growth factor receptor (HER2)-targeted antibody trastuzumab is a major clinical concern in the treatment of HER2-positive metastatic breast cancer. Increased expression or signaling from the insulin-like growth factor-1 receptor (IGF-1R) has been reported to be associated with trastuzumab resistance. However, the specific molecular and biologic mechanisms through which IGF-1R promotes resistance or disease progression remain poorly defined. In this study, we found that the major biologic effect promoted by IGF-1R was invasion, which was mediated by both Src-focal adhesion kinase (FAK) signaling and Forkhead box protein M1 (FoxM1). Cotargeting IGF-1R and HER2 using either IGF-1R antibodies or IGF-1R short hairpin RNA in combination with trastuzumab resulted in significant but modest growth inhibition. Reduced invasion was the most significant biologic effect achieved by cotargeting IGF-1R and HER2 in trastuzumab-resistant cells. Constitutively active Src blocked the anti-invasive effect of IGF-1R/HER2 cotargeted therapy. Furthermore, knockdown of FoxM1 blocked IGF-1-mediated invasion, and dual targeting of IGF-1R and HER2 reduced expression of FoxM1. Reexpression of FoxM1 restored the invasive potential of IGF-1R knockdown cells treated with trastuzumab. Overall, our results strongly indicate that therapeutic combinations that cotarget IGF-1R and HER2 may reduce the invasive potential of cancer cells that are resistant to trastuzumab through mechanisms that depend in part on Src and FoxM1

Influencing Gender Specific Perceptions of the Factors Affecting Women’s Career Advancement Opportunities in the United States

This research investigates the sociological, psychological, and physiological factors known to affect women’s career advancement opportunities. It examines how awareness and knowledge shared through the #MeToo (hashtag Me Too) movement influenced gender specific perceptions about the factors affecting women’s workplace opportunities. Finally, it recommends measures to alter the divergent gender perceptions that remain an obstacle to gender equality in the workplace. This study was conducted because gender inequalities continue in the U.S. workplace in 2018. Currently women fail to advance in careers at the same rate as men, and they are paid 21% less for similar work with equal skills and experience. Women comprise approximately 51% of the U.S. population and 47% of the workforce, so equality would dictate a one-to-one male to female ratio throughout all levels of government and private industry. The current male to female ratio in the U.S. Congress is four-to-one. The male to female executive ratio in Fortune 500 companies is three-to-one, and in the U.S. Government it is two-to-one. The researcher conducted a mixed method experimental study by comparing pre- and post-treatment interview and survey data to determine how much awareness and knowledge shared through the #MeToo mass media event impacted gender specific perceptions of women’s equality struggles in the workplace. The qualitative interview analysis indicated a moderate shift from divergent gender perceptions in Study 1 to convergent viewpoints in Study 2 following the #MeToo media events. The quantitative analysis of pre- and post-treatment survey studies supported the qualitative findings and showed a 43% reduction in the gender perception gap in the post-event assessment. With outcomes from three independent qualitative and quantitative investigations aligning, the researcher concluded the overall statistical results demonstrate a strong impact on men’s and women’s perceptions and a largely reduced gender perception gap following the #MeToo media events. Because it is unknown if those changes are permanent, the researcher believes future research could focus on awareness, education, and accountability initiatives to more adequately address gender equality problems in the workplace and bring about lasting change

Calculating Ex-ante Utilities From the modified Japanese Orthopedic Association Score: A Prerequisite for Quantifying the Value of Care for Cervical Myelopathy

STUDY DESIGN: General population utility valuation study. OBJECTIVE: The aim of this study was to develop a technique for calculating utilities from the modified Japanese Orthopedic Association (mJOA) Score. SUMMARY OF BACKGROUND DATA: The ability to calculate quality-adjusted life-years (QALYs) for degenerative cervical myelopathy (DCM) would enhance treatment decision making and facilitate economic analysis. QALYs are calculated using utilities. METHODS: We recruited a sample of 760 adults from a market research panel. Using an online discrete choice experiment, participants rated eight choice sets based on mJOA health states. A multiattribute utility function was estimated using a mixed multinomial-logit regression model. The sample was partitioned into a training set used for model fitting and validation set used for model evaluation. RESULTS: The regression model demonstrated good predictive performance on the validation set with an area under the curve of 0.81 (95% confidence interval: 0.80-0.82)). The regression model was used to develop a utility scoring rubric for the mJOA. Regression results revealed that participants did not regard all mJOA domains as equally important. The rank order of importance was (in decreasing order): lower extremity motor function, upper extremity motor function, sphincter dysfunction, upper extremity sensation. CONCLUSION: This study provides a simple technique for converting the mJOA score to utilities and quantify the importance of mJOA domains. The ability to evaluate QALYs for DCM will facilitate economic analysis and patient counseling. Clinicians should heed these findings and offer treatments that maximize function in the attributes viewed most important by patients.Level of Evidence: 3

Ultrasound findings in asymptomatic patients with modular metal on metal total hip arthroplasty.

OBJECTIVE: The use of metal-on-metal and modular total hip arthroplasty is associated with potentially serious local and systemic complications. The primary aim of this study was to identify the prevalence of a pseudotumor in asymptomatic patients with a particular metal-on-metal hip prosthesis after a minimum follow-up of 5 years using ultrasound evaluation. A secondary purpose was to identify associations between the presence of pseudotumor and serum metal ion levels following implantation. METHODS: We prospectively evaluated data collected from 36 asymptomatic patients who underwent implantation of a Profemur Z metal-on-metal total hip arthroplasty from January 2004 to January 2010. Serum metal ion levels were collected in 2012 and 2015. Hip ultrasounds were performed in 2015. RESULTS: Pseudotumors were found in 7/36 patients (19.4%). The average pseudotumor size measured 38.2 cm3 (range 7.35 cm3-130.81 cm3). Elevated metal ion levels were found in all patients at all time points. No statistical correlation was found between the presence of pseudotumor and patient age, age of the implant, component design, and any of the serum metal ion levels or ratios. CONCLUSIONS: One in every five asymptomatic patients with metal-on-metal implants was found to have a periarticular pseudotumor. There was no dose-dependent relationship found between elevated serum metal ion levels and the development of a pseudotumor. Our findings suggest that in patients with known elevated metal ion levels, continued monitoring of ion levels may not be a reliable predictor of pseudotumor formation, and ultrasound surveillance can and should be routinely used to document the presence and progression of pseudotumor

Calculating ex-ante Utilities From the Neck Disability Index Score: Quantifying the Value of Care For Cervical Spine Pathology

STUDY DESIGN: General population utility valuation study. OBJECTIVE: To develop a technique for calculating utilities from the Neck Disability Index (NDI) score. METHODS: We recruited a sample of 1200 adults from a market research panel. Using an online discrete choice experiment (DCE), participants rated 10 choice sets based on NDI health states. A multi-attribute utility function was estimated using a mixed multinomial-logit regression model (MIXL). The sample was partitioned into a training set used for model fitting and validation set used for model evaluation. RESULTS: The regression model demonstrated good predictive performance on the validation set with an AUC of .77 (95% CI: .76-.78). The regression model was used to develop a utility scoring rubric for the NDI. Regression results also revealed that participants did not regard all NDI items as equally important. The rank order of importance was (in decreasing order): pain intensity = work; personal care = headache; concentration = sleeping; driving; recreation; lifting; and lastly reading. CONCLUSIONS: This study provides a simple technique for converting the NDI score to utilities and quantify the relative importance of individual NDI items. The ability to evaluate quality-adjusted life-years using these utilities for cervical spine pain and disability could facilitate economic analysis and aid in allocation of healthcare resources

Rates and risk factors associated with 30- and 90-day readmissions and reoperations after spinal fusions for adult lumbar degenerative pathology and spinal deformity

PURPOSE: Analyze state databases to determine variables associated with of short-term readmissions and reoperations following thoracolumbar spine fusions for degenerative pathology and spinal deformity. METHODS: Retrospective study of State Inpatient Database (2005-13, CA, NE, NY, FL, NC, UT). INCLUSION CRITERIA: age \u3e 45 years, diagnosis of degenerative spinal deformity, ≥ 3 level posterolateral lumbar spine fusion. EXCLUSION CRITERIA: revision surgery, cervical fusions, trauma, and cancer. Univariate and step-wise multivariate logistic regression analyses were performed to identify independent variables associated with of 30- and 90-day readmissions and reoperations. RESULTS: 12,641 patients were included. All-cause 30- and 90-day readmission rates were 14.6% and 21.1%, respectively. 90-day readmissions were associated with: age \u3e 80 (OR: 1.42), 8 + level fusions (OR: 1.19), hospital length of stay (LOS) \u3e 7 days (OR: 1.43), obesity (OR: 1.29), morbid obesity (OR: 1.66), academic hospital (OR: 1.13), cancer history (OR:1.21), drug abuse (OR: 1.31), increased Charlson Comorbidity index (OR: 1.12), and depression (OR: 1.20). Private insurance (OR: 0.64) and lumbar-only fusions (OR: 0.87) were not associated with 90-day readmissions. All-cause 30- and 90-day reoperation rates were 1.8% and 4.2%, respectively. Variables associated with 90-day reoperations were 8 + level fusions (OR: 1.28), LOS \u3e 7 days (OR: 1.43), drug abuse (OR: 1.68), osteoporosis (OR: 1.26), and depression (OR: 1.23). Circumferential fusion (OR: 0.58) and lumbar-only fusions (OR: 0.68) were not associated with 90-day reoperations. CONCLUSIONS: 30- and 90-day readmission and reoperation rates in thoracolumbar fusions for adult degenerative pathology and spinal deformity may have been underreported in previously published smaller studies. Identification of modifiable risk factors is important for improving quality of care through preoperative optimization

Origins of eponymous instruments in spine surgery.

Every day, spine surgeons call for instruments named after surgical pioneers. Few know the designers or the histories behind their instruments. In this paper the authors provide a historical perspective on the Penfield dissector, Leksell rongeur, Hibbs retractor, Woodson elevator, Kerrison rongeur, McCulloch retractor, Caspar pin retractor system, and Cloward handheld retractor, and a biographical review of their inventors. Historical data were obtained by searching the HathiTrust Digital Library, PubMed, Google Scholar, Google Books, and Google, and personal communications with relatives, colleagues, and foundations of the surgeon-designers. The authors found that the Penfield dissectors filled a need for delicate tools for manipulating the brain and that the Leksell rongeur increased surgical efficiency during war-related laminectomies. Hibbs\u27 retractor facilitated his spine fusion technique. Woodson was both a dentist and a physician whose instrument was adopted by spine surgeons. Kerrison rongeurs were developed in otology to decompress bone near the facial nerve. The McCulloch, Caspar, and Cloward retractors helped improve exposure during the emergence of new techniques, i.e., microdiscectomy and anterior cervical discectomy and fusion. The histories behind these eponymous instruments remind us that innovation sometimes begins in other specialties and demonstrate the role of innovation in improving patient care