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INTRODUCTION: Adult spinal deformity (ASD) treatment for patients with osteoporosis presents a unique challenge for spine surgeons, particularly with ensuring adequate fixation and correction during surgery and due to the risk of treatment failure and complications thereafter. Osteoporosis is characterized by low bone mineral density (BMD) which may increase the risk for fractures. Approximately 12.6% of all adults over 50 years old in the United States are affected by osteoporosis, and the prevalence is predicted to increase with the aging population.1 ASD patients experience substantially higher rates of osteoporosis compared to the general population.2,3 One study discovered an osteoporosis prevalence of nearly 33% in a cohort of ASD patients undergoing long spinal fusion at two academic medical centers, with slightly over one- third of those patients receiving osteoporosis pharmacotherapy prior to surgery.3 Similarly, patients with osteoporosis experience ASD at higher rates than the general population, with one study finding that 9.5% of patients with osteoporosis suffer from ASD symptoms.3 Gupta et al. discovered that obtaining a DEXA scan of the forearm in addition to the hip allowed physicians to detect an additional 17% incidence of osteoporosis in ASD patients, suggesting that osteoporosis may be missed when there is only one DEXA scan available.4In addition to being potentially underdiagnosed and undertreated, ASD patients with osteoporosis experience higher rates of post-surgical complications. Pseudarthrosis, or nonunion after spinal fusion, is a painful and potentially debilitating complication following ASD surgery that ultimately requires additional surgical correction. Proximal junctional kyphosis (PJK), which is defined as proximal junctional sagittal Cobb angle ≥ 10° and at least 10° greater than the preoperative measurement, is another complication of ASD surgery.5 Though this condition may be clinically silent and manifest purely as a radiographic diagnosis, it is often a precursor to proximal junctional failure (PJF), a more severe form of PJK that ultimately increases the risk for intractable pain, neurological deficit, and revision surgery.6 ASD patients with osteoporosis experience significantly higher rates of pseudarthrosis, PJK, PJF, and postoperative fractures, as well as other forms of instrumentation failure requiring additional surgical treatment.7-11 This ultimately increases the pain, emotional burden, and morbidity experienced by patients. There is currently conflicting data regarding the impact of perioperative osteoporosis pharmacotherapy on outcomes in ASD patients. Bisphosphonates are considered first-line treatment for osteoporosis, though alternatives such as teriparatide, denosumab, and calcitonin may be used as well.12 Multiple studies have found that preoperative bisphosphonate treatment did not affect lumbar fusion nonunion rates.13,14 In contrast, a meta-analysis of randomized control trials found that postoperative bisphosphonates had no effect on lumbar fusion rates but did significantly reduce the risk of vertebral compression fracture (VCF) and pedicle screw loosening at 12-month follow-up.15 Prophylactic teriparatide treatment has been associated with improved BMD and lower incidence of PJK type-2 in osteoporosis patients who underwent ASD surgery.16 Evidence for perioperative treatment of teriparatide as a preventative step to increase fusion rates and reduce PJK and PJF is strongest.17 However, the percentage of ASD patients who are actually being treated perioperatively with these medications requires further evaluation, and a comparison of outcomes with osteoporosis and non-osteoporosis counterparts has yet to be explored. The purpose of this study was to evaluate the prevalence and treatment of osteoporosis among patients undergoing long spinal fusion for ASD, as well as compare the impact of osteoporosis treatment on surgical and radiographic outcomes following fusion surgery. Additionally, we sought to examine the differences in radiographic outcomes of osteoporotic patients receiving various pharmacologic regimens such as monotherapy vs combination therapy.
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A fracture liaison service is a systems-level multidisciplinary approach designed to reduce subsequent fracture risk in patients who recently sustained fragility fractures. It is estimated that one in three women and one in five men over the age of 50 years old have osteoporosis. Nonetheless, only 9 to 20% of patients who sustain an initial fragility fracture eventually receive any osteoporosis treatment. With the aim of preventing subsequent fractures, a fracture liaison service (FLS) works through identifying patients presenting with fragility fractures to the hospital and providing them with easier access to osteoporosis care through referrals for bone health and fracture risk assessment and recommendation or initiation of osteoporosis treatment. Currently, there are four major types of FLS models ranging from services that only identify at-risk patients and inform and educate the patient but take no further part in communicating their findings to other stakeholders in patients' care, to services that identify, investigate, and initiate treatment at the other end of the spectrum. In this article, we review the benefits, challenges, and outcomes of FLS in the American healthcare system with further exploration of the roles each member of the multidisciplinary team can play in improving patients' bone health.
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Background The United States Medical Licensing Exam (USMLE) Step 1 was recently changed from a numerically scored grading system to a pass/fail grading system. Until late 2024, there will be no formal studies about the impact that the grading change will have on the match process. To thoroughly assess the impact that this change will have on the overall match process, it is important to look at what the trends in applicants' objective measures have been in the years before the change. We aim to systematically evaluate the rates of change and mean trend of objective metrics found in residency applications in the main residency match. Methods Objective medical student data of matched and unmatched applicants were queried from the National Matching Program's Charting Outcomes in the Match Reports for the 2007 to 2020 application cycles. Data were used to create linear regression analyses and statistical tests were performed to evaluate trends over time. Results For matched applicants, there were statistically significant positive trends for the mean number of contiguous ranks (m=0.33, p<0.01), having another non-doctoral graduate degree (m=0.67, p<0.01), membership to Alpha Omega Alpha (AOA) honor society (m=0.22, p<0.01), mean USMLE Step 1 score (m=1.01, p<0.01), mean USMLE Step 2 score (m=1.68, p<0.01), mean number of research experiences (m=0.12, p<0.01), and mean number of abstracts, presentations, and publications (m=0.34, p<0.01). Additionally, there was a statistically significant negative trend for the percentage who graduated from a top 40 National Institutes of Health-funded medical school (m=-0.41, p<0.01). For unmatched applicants, there were statistically significant positive trends for having another non-doctoral graduate degree (m=0.83, p<0.01), mean USMLE Step 1 score (m=1.26, p<0.01), mean USMLE Step 2 score (m=2.27, p<0.01), mean number of research experiences (m=0.13, p<0.01), and mean number of abstracts, presentations, and publications (m=0.33, p<0.01). Conclusion Our study shows that there have been statistically significant increases in almost all objective measures in the residency application. Recent changes to the abstracts, presentations, and publications on the Step 1 scoring system will force almost all residency programs to overhaul their application process and potentially increase reliance on Step 2, research, and other nonobjective factors. For students early in their medical education, emphasis on Step 2 and research will yield increased chances of matching into residency in the future.
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BACKGROUND: With recent interest in patient-specific dosimetry for radiopharmaceutical therapy (RPT) and selective internal radiation therapy (SIRT), an increasing number of voxel-based algorithms are being evaluated. Monte Carlo (MC) radiation transport, generally considered to be the most accurate among different methods for voxel-level absorbed dose estimation, can be computationally inefficient for routine clinical use. PURPOSE: This work demonstrates a recently implemented grid-based linear Boltzmann transport equation (LBTE) solver for fast and accurate voxel-based dosimetry in RPT and SIRT and benchmarks it against MC. METHODS: A deterministic LBTE solver (Acuros MRT) was implemented within a commercial RPT dosimetry package (Velocity 4.1). The LBTE is directly discretized using an adaptive mesh refined grid and then the coupled photon-electron radiation transport is iteratively solved inside specified volumes to estimate radiation doses from both photons and charged particles in heterogeneous media. To evaluate the performance of the LBTE solver for RPT and SIRT applications, 177Lu SPECT/CT, 90Y PET/CT, and 131I SPECT/CT images of phantoms and patients were used. Multiple lesions (2-1052 mL) and normal organs were delineated for each study. Voxel dosimetry was performed with the LBTE solver, dose voxel kernel (DVK) convolution with density correction, and a validated in-house MC code using the same time-integrated activity and density maps as input to the different dose engines. The resulting dose maps, difference maps, and dose-volume-histogram (DVH) metrics were compared, to assess the voxel-level agreement. Evaluation of mean absorbed dose included comparison with structure-level estimates from OLINDA. RESULTS: In the phantom inserts/compartments, the LBTE solver versus MC and DVK convolution demonstrated good agreement with mean absorbed dose and DVH metrics agreeing to within 5% except for the D90 and D70 metrics of a very low activity concentration insert of 90Y where the agreement was within 15%. In the patient studies (five patients imaged after 177Lu DOTATATE RPT, five after 90Y SIRT, and two after 131I radioimmunotherapy), in general, there was better agreement between the LBTE solver and MC than between LBTE solver and DVK convolution for mean absorbed dose and voxel-level evaluations. Across all patients for all three radionuclides, for soft tissue structures (kidney, liver, lesions), the mean absorbed dose estimates from the LBTE solver were in good agreement with those from MC (median difference < 1%, maximum 9%) and those from DVK (median difference < 5%, maximum 9%). The LBTE and OLINDA estimates for mean absorbed dose in kidneys and liver agreed to within 10%, but differences for lesions were larger with a maximum 14% for 177Lu, 23% for 90Y, and 26% for 131I. For bone regions, the agreement in mean absorbed doses between LBTE and both MC and DVK were similar (median < 11%, max 11%) while for lung the agreement between LBTE and MC (median < 1%, max 8%) was substantially better than between LBTE and DVK (median < 16%, max 33%). Voxel level estimates for soft tissue structures also showed good agreement between the LBTE solver and both MC and DVK with a median difference < 5% (maximum < 13%) for the DVH metrics with all three radionuclides. The largest difference in DVH metrics was for the D90 and D70 metric in lung and bone where the uptake was low. Here, the difference between LBTE and MC had a median value < 14% (maximum 23%) for bone and < 4% (maximum 37%) for lung, while the corresponding differences between LBTE and DVK were < 23% (maximum 31%) and < 67% (maximum 313%), respectively. For a typical patient with a matrix size of 166 × 166 × 129 (voxel size 3 × 3 × 3 mm3), voxel dosimetry using the LBTE solver was as fast as â¼2 min on a desktop computer. CONCLUSION: Having established good agreement between the LBTE solver and MC for RPT and SIRT applications, the LBTE solver is a viable option for voxel dosimetry that can be faster than MC. Further analysis is being performed to encompass the broad range of radionuclides and conditions encountered clinically.