Predictors of Reoperation and Survival Experience (Minimum One-Year) for Primary Versus Conversion Total Hip Arthroplasty in Young Patients.

BACKGROUND: Total hip arthroplasty (THA), including primary and conversion procedures, is commonly used for many types of joint disease in patients under 65 years old, though few studies have evaluated THA outcomes in young patients (≤ 40 years old). This study examined a large cohort of patients who underwent THA at a young (≤ 40) age to identify predictors of reoperation and compare survivorship between primary and conversion THAs. METHODS: A retrospective study was conducted on 497 patients who underwent 612 primary and conversion THAs at 40 years old or younger between 1990 and 2020. Medical records were reviewed to collect patient and surgical data. A multivariable logistic regression model identified independent predictors of reoperation, and Kaplan-Meier analysis with log-rank tests was used to compare survival curves by THA type. RESULTS: The median age at surgery (interquartile range) was 31.4 years old (25.4 to 36.3). The median follow-up time was 6.6 years (range, 3.8 to 10.5). Conversion THAs had an increased rate of both revisions (12.3 versus 5.6%, P = 0.02) and non-revision reoperations (8.9 versus 3.2%, P = 0.03) compared to primary THAs. A ceramic-on-ceramic articulation (odds ratio [OR]: 5.17; P = 0.03) and a higher estimated blood loss (OR: 1.0007; P = 0.03) were independent predictors of reoperation for primary and conversion THA, respectively. Conversion THAs had a lower 15-year survival (77.8 versus 90.8%, P = 0.009) compared to primary THAs, with no difference in survival between patients ≤ 30 years old and patients 31 to 40 years old for both primary and conversion THAs. CONCLUSIONS: Patients ≤ 40 years old who underwent primary and conversion THAs demonstrated an impressive 15-year survival comparable to that of older populations (74 to 93%), while conversion procedures had a higher reoperation rate. Though primary THA may be more ideal, there are promising outcomes for patients who need THA at a younger age than typically implemented, especially for those who are very young (≤ 30 years old).

Occipital condyle fracture in the pediatric population: A management algorithm and systematic review.

Purpose: This study aims to develop an accessible stepwise management algorithm for pediatric presentations of occipital condyle fractures (OCFs) based on a systematic review of the published literature regarding diagnostic evaluation, treatment, and outcomes. Methods: A systematic review of the literature was conducted on PubMed to locate English language studies reporting on the management of pediatric OCFs. Data extraction of clinical presentation, management strategies, imaging, and treatment outcome was performed. Results: A total of 15 studies reporting on 38 patients aged 18 years and younger presenting with OCFs were identified. Loss of consciousness (LOC), depressed level of consciousness, neck pain, decreased neck range of motion (ROM), and cranial nerve injury were the most common presenting symptoms. Diagnostic imaging included radiographs, computed tomography (CT) scans, magnetic resonance imaging (MRI), and functional radiographs to assess cervical stability. Treatment options varied and included soft collar, hard collar, and halo vest. All studies resulted in a complete healing of the OCF, with resolution of associated pain. Conclusion: The proposed treatment algorithm suggests a framework for the management of pediatric OCFs based on the available evidence (levels of evidence: 3, 4). This review of the literature indicated that a stepwise approach should be utilized in the management of isolated pediatric OCFs.

Predictors of reoperation and survival experience for primary total knee arthroplasty in young patients with degenerative and inflammatory arthritis.

INTRODUCTION: While total knee arthroplasty (TKA) is typically implemented in patients > 65 years old, young patients may need to undergo TKA for pain relief and functional improvement. Current data are limited by older cohorts and short-term survival rates. This study aimed to examine a large sample size of patients with degenerative and inflammatory conditions who underwent primary TKA at a young (≤ 40) age to identify predictors of reoperation, as well 15-year survivorship. MATERIALS AND METHODS: A retrospective study was performed on 77 patients (92 surgeries) who underwent primary TKA at ≤ 40 years old, between January 1990 and January 2020. Patient charts were reviewed and a multivariable logistic regression model identified independent predictors of reoperation. Kaplan-Meier analysis was employed to build survival curves and log-rank tests analyzed survival between groups. RESULTS: Of the 77 patients, the median age at the time of surgery was 35.7 years (IQR: 31.2-38.7) and median follow-up time was 6.88 years. Twenty-one (22.8%) primary TKAs underwent 24 reoperations, most commonly due to stiffness (n = 9, 32.1%) and infection (n = 13, 46.4%) more significantly in the OA group (p = 0.049). There were no independent predictors of reoperation in multivariable analysis, and 15-year revision-free survivorship after TKA did not differ by indication (77.3% for OA/PTOA vs. 96.7% for autoimmune, p = 0.09) or between ≤ 30 and 31-40 year age groups (94.7% vs. 83.6%, p = 0.55). CONCLUSIONS: In this cohort of patients ≤ 40 years old, revision-free survival was comparable to that reported in the literature for older TKA patients with osteoarthritis/autoimmune conditions (81-94% at 15-years). Though nearly a quarter of TKAs required reoperation and causes of secondary surgery differed between degenerative and inflammatory arthritis patients, there were no significant predictors of increased reoperation rate. Very young patients ≤ 30 years old did not have an increased risk of revision compared to those aged 31-40 years.

Association of Pharmacologic Treatment of Depression/Anxiety With Initial Patient-Reported Outcome Measures in Patients With Hip and Knee Osteoarthritis.

INTRODUCTION: Depression and anxiety are common comorbidities that may exacerbate osteoarthritis (OA)-related pain. We aim to evaluate the effect of pharmacologic treatment of depression/anxiety on hip and knee patient-reported outcome measures (PROMs). METHODS: A multi-institutional PROMs database was queried for patients with depression or anxiety and hip or knee OA who completed a PROMs questionnaire at an initial orthopaedic visit between January 2015 and March 2023. Data on demographics, comorbidities, and duration of pharmacologic treatment of depression/anxiety were obtained. Patients were stratified into three cohorts based on treatment duration. PROMs were compared across cohorts. RESULTS: Two thousand nine hundred sixty patients who completed PROMs at their initial orthopaedic visit had both OA and depression/anxiety. One hundred thirty-four (4.5%) received pharmacologic treatment of depression/anxiety for < 1 year, versus 196 (6.6%) for more than 1 year. In unadjusted analyses, patients with pharmacologic treatment had significantly lower Patient-Reported Outcomes Measurement Information System (PROMIS)-Physical (39.8 [IQR 34.9, 44.9] vs 42.3 [37.4, 47.7], P < 0.001) and PROMIS-Mental (43.5 [36.3, 50.8] vs 48.3 [41.1, 53.3], P < 0.001) scores than those without treatment. After adjusting for demographics and comorbidities, only differences in PROMIS-Mental scores remained statistically significant, with pharmacologic treatment associated with lower scores (ß = -2.26, 95% CI, [-3.29, -1.24], P < 0.001). On secondary analysis including duration of pharmacologic treatment, < 1 year of treatment was associated with significantly lower PROMIS-Mental scores than those not treated (ß = -4.20, 95% CI [-5.77, -2.62], P < 0.001) while scores of patients with more than 1 year of treatment did not differ significantly from those without treatment. CONCLUSION: :Our results indicate that pharmacologic treatment of depression/anxiety is associated with improved psychological health but not with improved physical symptoms related to OA. We observed a nonsignificant trend that patients with depression/anxiety who warrant pharmacologic treatment tend to have worse physical symptoms than those who do not; however, unadjusted analyses suggest this is a complex relationship beyond the isolated effect of pharmacologic treatment.

What Is the Most Effective Treatment for Periprosthetic Joint Infection After Total Joint Arthroplasty in Patients with Rheumatoid Arthritis?: A Systematic Review.

BACKGROUND: Rheumatoid arthritis (RA) is a risk factor for periprosthetic joint infection (PJI) after total joint arthroplasty (TJA). The purpose of this study was to perform a systematic review comparing the failure rates of debridement, antibiotics, and implant retention (DAIR), one-stage exchange arthroplasty/revision (OSR), and 2-stage exchange arthroplasty/revision (TSR) for RA patients with PJI and identify risk factors in the RA population associated with increased treatment failure rate. METHODS: PubMed, Ovid MEDLINE, and Ovid Embase databases were screened with the terms "rheumatoid arthritis," "total joint arthroplasty," "prosthetic joint infection," and "treatment for PJI" on August 29, 2021. Four hundred ninety-one studies were screened, of which 86 were evaluated. The primary outcome evaluated was failure of surgical treatment for PJI. RESULTS: Ten retrospective cohort studies were included after full-text screening, yielding 401 patients with RA. Additional demographic and PJI management data were obtained for 149 patients. Patients with RA who underwent TSR demonstrated a lower failure rate (26.8%) than both DAIR (60.1%) and OSR (39.2%) (χ2 = 37.463, p < 0.00001). Patients with RA who underwent DAIR had a 2.27 (95% CI, 1.66-3.10) times higher risk of experiencing treatment failure than those who underwent TSR. Among risk factors, there was a significant difference in the C-reactive protein of patients who did vs. did not experience treatment failure (p = 0.02). CONCLUSION: TSR has a higher rate of success in the management of PJI patients with RA compared with DAIR and OSR. The complete removal of the infected prosthesis and delayed reimplantation may lower the treatment failure rate. LEVEL OF EVIDENCE: Level III. See Instructions for Authors for a complete description of levels of evidence.

Association Between Posterior Tibial Slope and ACL Injury in Pediatric Patients: A Systematic Review and Meta-analysis.

BACKGROUND: The posterior tibial slope (PTS) has been proposed to be a radiographic risk factor for anterior cruciate ligament (ACL) injury in adults. However, this has not been well established in pediatric patients. PURPOSE: This systematic review and meta-analysis was performed to investigate any association between PTS and ACL tears in the pediatric population. STUDY DESIGN: Systematic review and meta-analysis; Level of evidence, 4. METHODS: A systematic review was performed to identify studies that examined the relationship between PTS, medial tibial slope (MTS), and lateral tibial slope (LTS) and ACL tears in children and adolescents aged ≤18 years. Full-text observational studies comparing PTS, MTS, and/or LTS values between pediatric (≤18 years of age) patients with and without ACL injury were included in this analysis. Review articles and case series were excluded. The authors calculated the mean difference (MD) via a restricted maximum-likelihood estimator for tau square and a Hartung-Knapp adjustment for random-effects model. RESULTS: A total of 348 articles were identified in the initial database search, yielding 10 for final inclusion and analysis. There was no statistically significant association between PTS (MD, 1.13°; 95% CI, -0.55° to 2.80°; P = .10), MTS (MD, 0.36°; 95% CI, -0.37° to 1.10°; P = .27), or LTS (MD, 1.41°; 95% CI, -0.20° to 3.02°; P = .075) and risk for ACL injury in this population. CONCLUSION: The current study found that unlike what has been shown in adult populations, increased PTS may not be a significant risk factor for ACL tears in pediatric and adolescent patents. LTS was the only measured parameter that neared statistical significance, perhaps suggesting a potential role for this measurement in determining ACL risk if further research is done in this population.

Utility of postoperative laboratory testing after posterior spinal fusion for adolescent idiopathic scoliosis.

PURPOSE: With advancements to blood management strategies, risk of perioperative transfusion following surgical treatment of adolescent idiopathic scoliosis (AIS) has diminished. We hypothesize that routine laboratory testing on postoperative-day 1 (POD1) and beyond is unnecessary. The purpose of this study is to determine necessity of POD1 labs, particularly hematocrit and hemoglobin levels, following surgical management of AIS. METHODS: We performed a retrospective cohort study of consecutive AIS patients aged 11-19 who underwent posterior spinal fusion (PSF) at a single institution. Univariable logistic regression was utilized to determine factors associated with hematocrit ≤ 22% on POD1 or a postoperative transfusion. Firth's penalized logistic regression was used for any separation in data. Youden's index was utilized to determine the optimal point on the ROC curve that maximizes both sensitivity and specificity. RESULTS: 527 patients qualified for this study. Among the eight total patients with POD1 hematocrit ≤ 22, none underwent transfusion. These patients had lower last intraoperative hematocrit levels compared to patients with POD1 hematocrit > 22% (24.1% vs 31.5%, p < 0.001), and these groups showed no difference in preoperative hematocrit levels (38.2% vs 39.8%, p = 0.11). Four patients underwent postoperative transfusion. Both preoperative hematocrit levels (34.0% vs 39.9%, p = 0.001) and last intraoperative hematocrit levels (25.1% vs 31.4%, p = 0.002) were lower compared to patients without transfusion. Intraoperative hematocrit < 26.2%, operative time of more than 35.8 min per level fused, or cell salvage > 241 cc were significant risk factors for postoperative transfusion. CONCLUSION: Transfusion after PSF for AIS is exceedingly rare. POD1 labs should be considered when last intraoperative hematocrit < 26%, operative time per level fused > 35 min, or cell salvage amount > 241 cc. Otherwise, unless symptomatic, patients do not benefit from postoperative laboratory screening.

Efficiency and perceived safety of foot and ankle procedures performed on the preoperative stretcher versus operating room table.

BACKGROUND: Foot and ankle surgeons often perform minor surgeries on the preoperative stretcher instead of the operating room table. We examined whether stretcher-based and operating room table-based procedures differed with respect to operating room efficiency and staff perceptions. METHODS: We retrospectively reviewed medical records of patients undergoing minor foot and ankle surgery at an ambulatory surgery centre. We collected 'time to start', the duration between patient arrival in the operating room and incision time, and 'time to exit', the duration between procedure end time and patient exit from the operating room. Staff were surveyed regarding their perceptions of stretcher-based and operating room table-based procedures. RESULTS: 'Time to start' was significantly shorter for stretcher-based procedures, but 'time to exit' was not. Seventeen (81%) staff members thought stretcher-based procedures increased operating room efficiency. Thirteen (62%) thought stretcher-based procedures bettered staff safety. Nineteen (91%) thought stretcher-based procedures were equivalent to or better than operating room table-based procedures for patient safety. Most (67%) would recommend stretcher-based procedures. CONCLUSION: We found small but significant time savings associated with stretcher-based procedures. Without adapting surgical scheduling practices, the impact of stretcher-based procedures on overall operating room efficiency is questionable. Nevertheless, the majority of OR staff think stretcher-based procedures increase OR efficiency and are safer for staff. LEVEL OF EVIDENCE: Level IV, Retrospective case series.

Spinal osteoid osteoma in the pediatric population: A management algorithm and systematic review.

Purpose: The purpose of this study is to develop an accessible step-wise management algorithm for the management of pediatric spinal osteoid osteomas (OOs) based on a systematic review of the published literature regarding the diagnostic evaluation, treatment, and outcomes following surgical resection. Methods: A systematic review of the literature was conducted on PubMed to locate English language studies reporting on the management of pediatric spinal OOs. Data extraction of clinical presentation, management strategies and imaging, and treatment outcomes were performed. Results: Ten studies reporting on 85 patients under the age of 18 years presenting with OOs were identified. Back pain was the most common presenting symptom, and scoliosis was described in 8 out of 10 studies, and radicular pain in 7 out of 10 studies. Diagnostic, intraoperative, and postoperative assessment included radiographs, computed tomography (CT) scans, magnetic resonance imaging (MRI), bone scans, and frozen section. Treatment options varied, including conservative management, open surgical resection with or without intraoperative imaging, and percutaneous image-guided treatment. All included studies described partial or complete resolution of pain in the immediate postoperative period. Conclusions: The proposed algorithm provides a suggested framework for management of pediatric spinal OOs based on the available evidence (levels of evidence: 3, 4). This review of the literature indicated that a step-wise approach should be utilized in the management of pediatric spinal OOs.

A pilot investigation of muscle integrity in patients with ADSSL1 myopathy using electrical impedance myography.

INTRODUCTION/AIMS: ADSSL1 myopathy (OMIM 617030) is a recently discovered, congenital myopathic disease caused by a pathogenic variant in ADSSL1. ADSSL1 is an enzyme involved in the purine nucleotide process and facilitates the conversion of inosine monophosphate to adenosine monophosphate within myocytes. Electrical impedance myography (EIM) is a portable, non-invasive, and cost-effective method for characterizing muscle integrity. Three ADSSL1 patients are presented in whom characterization of muscle integrity using EIM was performed. METHODS: A 15-y-old male, 20-y-old female, and 63-y-old male each with a pathogenic variant in ADSSL1 [c.901G > A] as well as three, age-gender matched healthy controls (HCs) were enrolled. Study participants were phenotyped using a virtual EIM procedure. RESULTS: ADSSL1 myopathy patients presented with variable onset of physical disability, disease progression, and severity of muscle weakness. Across multiple proximal and distal muscles groups and relative to HCs, ADSSL1 myopathy patients demonstrated lower phase and reactance values, while resistance was higher, which together indicated diseased muscle. DISCUSSION: EIM can provide a novel, non-invasive and objective biomarker to evaluate muscle integrity in patients with ADSSL1 myopathy. Combining EIM with musculoskeletal imaging and histologic assessments in follow-up studies may further inform on the pathophysiology of ADSSL1 myopathy.

Trends in non-operative management of low-energy pelvic fracture: An analysis of the Nationwide Inpatient Sample.

Introduction: Non-operative management is common for low-impact pelvic fractures. In this study, we characterize the epidemiology of those treated nonoperatively following low-energy pelvic fracture, while identifying recent management trends. Methodology: Data from the Nationwide Inpatient Sample (NIS) database from 2011 to 2018 were analyzed. We identified adult patients diagnosed with pelvic fracture based on International Classification of Diseases (ICD) codes, excluding fractures of the acetabulum, femur, polytrauma, and open fractures to isolate cases caused by low-impact mechanisms. Codes indicating operative management were excluded. Demographic information and outcomes (length of stay, in-hospital mortality, hospital discharge status) were collected. Sub-analyses were performed to identify trends. Findings: 123,936 eligible patients were identified. The average age was 68.7 years. 70% were female, showing a decline from 75% to 66% over the study period. Pubic bone involvement was observed in 59% of fractures. The mean Charlson Comorbidity Index (CCI) was 3.83, corresponding to a 10-year survival rate of 58.5%, which remained relatively stable throughout the study period. 62.4% of patients received treatment at urban teaching hospitals. Average length of hospital stay was 6.3 days. Discharge to a skilled nursing facility (SNF) was the most common outcome, ranging from 62.1% to 65.0% during the study period, while 20.0% of patients were discharged home (18.4%-21.1%). Mean in-hospital mortality was 3.28%, showing no significant change, with higher rates among male patients (5.1%) and patients of Asian descent (3.8%). Conclusion: The majority of patients receiving nonoperative treatment for low-energy pelvic fractures were females in their mid-60s with moderate comorbidity. The study reveals a relatively high in-hospital mortality rate of 3.28%, particularly among male patients and those of Asian descent, indicating the need for increased surveillance for further injury in these groups. Most patients were discharged to a SNF, highlighting the necessity for extended rehabilitation in this population. This persistent trend is noteworthy considering the growing emphasis on the cost of inpatient admissions and advancements in outpatient management of orthopedic injuries.

Operative and Nonoperative Treatment of Humeral Shaft Fractures: A Cost-Effectiveness Analysis.

BACKGROUND: Decision-making with regard to the treatment of humeral shaft fractures remains under debate. The cost-effectiveness of these treatment options has yet to be established. This study aims to compare the cost-effectiveness of operative treatment with that of nonoperative treatment of humeral shaft fractures. METHODS: We developed a decision tree for treatment options. Surgical costs included the ambulatory surgical fee, physician fee, anesthesia fee, and, in the sensitivity analysis, lost wages during recovery. We used the Current Procedural Terminology codes from the American Board of Orthopaedic Surgery to determine physician fees via the U.S. Centers for Medicare & Medicaid Services database. The anesthesia fee was obtained from the national conversion factor and mean operative time for included procedures. We obtained data on mean wages from the U.S. Bureau of Labor and data on weeks missed from a similar study. We reported functional data via the Disabilities of the Arm, Shoulder and Hand (DASH) scores obtained from existing literature. We used rollback analysis and Monte Carlo simulation to determine the cost-effectiveness of each treatment option, presented in dollars per meaningful change in DASH score, utilizing a $50,000 willingness-to-pay (WTP) threshold. RESULTS: The cost per meaningful change in DASH score for operative treatment was $18,857.97 at the 6-month follow-up and $25,756.36 at the 1-year follow-up, by Monte Carlo simulation. Wage loss-inclusive models revealed values that fall even farther below the WTP threshold, making operative management the more cost-effective treatment option compared with nonoperative treatment in both settings. With an upward variation of the nonoperative union rate to 84.17% in the wage-exclusive model and 89.43% in the wage-inclusive model, nonoperative treatment instead became more cost-effective. CONCLUSIONS: Operative management was cost-effective at both 6 months and 1 year, compared with nonoperative treatment, in both models. Operative treatment was found to be even more cost-effective with loss of wages considered, suggesting that an earlier return to baseline function and, thus, return to work are important considerations in making operative treatment the more cost-effective option. LEVEL OF EVIDENCE: Economic and Decision Analysis Level III . See Instructions for Authors for a complete description of levels of evidence.

Diminished muscle integrity in patients with fibrodysplasia ossificans progressiva assessed with at-home electrical impedance myography.

Fibrodysplasia ossificans progressiva (FOP) is an ultra-rare disorder involving skeletal dysplasia and heterotopic ossification (HO) of muscle and connective tissue. We aimed to define a novel biomarker in FOP that enables reliable assessment of musculoskeletal tissue integrity. Considering logistical difficulties that FOP patients often face, our goal was to identify an at-home biomarker technique. Electrical impedance myography (EIM) is a non-invasive, portable method that can inform on muscle health. 15 FOP patients (age 10-52) and 13 healthy controls were assessed. Using EIM, multiple muscle groups were characterized per participant in a 45-min period. The Cumulative Analogue Joint Involvement Scale (CAJIS) was implemented to determine mobility burden severity. We additionally evaluated physical activity levels via a Patient-Reported Outcomes Measurement Information System (PROMIS)-based questionnaire. Relative to controls, FOP patients demonstrated significantly lower regional and whole-body phase values at 50 kHz and 100 kHz, indicating more diseased muscle tissue. Lower whole-body phase and reactance values, and higher resistance values, were associated with greater FOP burden (CAJIS score range: 4-30) and lower physical activity levels at 50 kHz and 100 kHz. This study points to the potential utility of EIM as a clinical biomarker tool capable of characterizing muscle integrity in FOP.

Cost-Effectiveness of Arthroscopic Partial Meniscectomy and Physical Therapy for Degenerative Meniscal Tear.

OBJECTIVE: We examined the cost-effectiveness of treatment strategies for concomitant meniscal tear and knee osteoarthritis (OA) involving arthroscopic partial meniscectomy surgery and physical therapy (PT). METHODS: We used the Osteoarthritis Policy Model, a validated Monte Carlo microsimulation, to compare three strategies, 1) PT-only, 2) immediate surgery, and 3) PT + optional surgery, for participants whose pain persists following initial PT. We modeled a cohort with baseline meniscal tear, OA, and demographics from the Meniscal Tear in Osteoarthritis Research (MeTeOR) trial of arthroscopic partial meniscectomy versus PT. We estimated risks and costs of arthroscopic partial meniscectomy complications and accounted for heightened OA progression post surgery using published data. We estimated surgery use rates and treatment efficacies using MeTeOR data. We considered a 5-year time horizon, discounted costs, and quality-adjusted life-years (QALYs) 3% per year and conducted sensitivity analyses. We report incremental cost-effectiveness ratios. RESULTS: Relative to PT-only, PT + optional surgery added 0.0651 QALY and $2,010 over 5 years (incremental cost-effectiveness ratio = $30,900 per QALY). Relative to PT + optional surgery, immediate surgery added 0.0065 QALY and $3080 (incremental cost-effectiveness ratio = $473,800 per QALY). Incremental cost-effectiveness ratios were sensitive to optional surgery efficacy in the PT + optional surgery strategy. In the probabilistic sensitivity analysis, PT + optional surgery was cost-effective in 51% of simulations at willingness-to-pay thresholds of both $50,000 per QALY and $100,000 per QALY. CONCLUSION: First-line arthroscopic partial meniscectomy has a prohibitively high incremental cost-effectiveness ratio. Under base case assumptions, second-line arthroscopic partial meniscectomy offered to participants with persistent pain following initial PT is cost-effective at willingness-to-pay thresholds between $31,000 and $473,000 per QALY. Our analyses suggest that arthroscopic partial meniscectomy can be a high-value treatment option for patients with meniscal tear and OA when performed following an initial PT course and should remain a covered treatment option.

MRI-based assessment of proximal femur strength compared to mechanical testing.

Half of the women who sustain a hip fracture would not qualify for osteoporosis treatment based on current DXA-estimated bone mineral density criteria. Therefore, a better approach is needed to determine if an individual is at risk of hip fracture from a fall. The objective of this study was to determine the association between radiation-free MRI-derived bone strength and strain simulations compared to results from direct mechanical testing of cadaveric femora. Imaging was conducted on a 3-Tesla MRI scanner using two sequences: one balanced steady-state free precession sequence with 300 µm isotropic voxel size and one spoiled gradient echo with anisotropic voxel size of 234 × 234 × 1500 µm. Femora were dissected free of soft-tissue and 4350-ohm strain-gauges were securely applied to surfaces at the femoral shaft, inferior neck, greater trochanter, and superior neck. Cadavers were mechanically tested with a hydraulic universal test frame to simulate loading in a sideways fall orientation. Sideways fall forces were simulated on MRI-based finite element meshes and bone stiffness, failure force, and force for plastic deformation were computed. Simulated bone strength metrics from the 300 µm isotropic sequence showed strong agreement with experimentally obtained values of bone strength, with stiffness (r = 0.88, p = 0.0002), plastic deformation point (r = 0.89, p < 0.0001), and failure force (r = 0.92, p < 0.0001). The anisotropic sequence showed similar trends for stiffness, plastic deformation point, and failure force (r = 0.68, 0.70, 0.84; p = 0.02, 0.01, 0.0006, respectively). Surface strain-gauge measurements showed moderate to strong agreement with simulated magnitude strain values at the greater trochanter, superior neck, and inferior neck (r = -0.97, -0.86, 0.80; p ≤0.0001, 0.003, 0.03, respectively). The findings from this study support the use of MRI-based FE analysis of the hip to reliably predict the mechanical competence of the human femur in clinical settings.

The Effect of Inflammation on Bone.

Bone remodeling is the continual process to renew the adult skeleton through the sequential action of osteoblasts and osteoclasts. Nuclear factor RANK, an osteoclast receptor, and its ligand RANKL, expressed on the surface of osteoblasts, result in coordinated control of bone remodeling. Inflammation, a feature of illness and injury, plays a distinct role in skewing this process toward resorption. It does so via the interaction of inflammatory mediators and their related peptides with osteoblasts and osteoclasts, as well as other immune cells, to alter the expression of RANK and RANKL. Such chemical mediators include TNFα, glucocorticoids, histamine, bradykinin, PGE2, systemic RANKL from immune cells, and interleukins 1 and 6. Conditions, such as periodontal disease and alveolar bone erosion, aseptic prosthetic loosening, rheumatoid arthritis, and some sports related injuries are characterized by the result of this process. A thorough understanding of bone response to injury and disease, and ability to detect such biomarkers, as well as imaging to identify early structural and mechanical property changes in bone architecture, is important in improving management and outcomes of bone related pathology. While gut health and vitamin and mineral availability appear vitally important, nutraceuticals also have an impact on bone health. To date most pharmaceutical intervention targets inflammatory cytokines, although strategies to favorably alter inflammation induced bone pathology are currently limited. Further research is required in this field to advance early detection and treatments.

Curing Hepatitis C in Liver Transplant Recipients Is Associated with Changes in Immunosuppressant Use.

BACKGROUND AND AIMS: All-oral interferon-free antivirals are highly effective in treating recurrent hepatitis C (HCV) infection in liver transplant (LT) recipients. The aim of the study was to assess immunosuppression needs after achieving a sustained viral response (SVR). METHODS: We compared immunosuppression needs before and after achieving a SVR in adult LT recipients treated for recurrent HCV infection with all-oral direct acting agents. RESULTS: We identified 52 liver LT treated recipients who achieved a SVR. The median (25th and 75th percentile interquartile range [IQR]) age was 62 years (57.75, 65). Most recipients received tacrolimus (TAC) for their immunosuppressant regimen. After achieving SVR, there was no statistically significant difference in daily dose of TAC unadjusted per weight (p > 0.05). However, there was a statistically significant decrease in daily dose of TAC adjusted per weight, serum levels of TAC, and the product of glomerular filtration rate and TAC. No statistically significant differences in cyclosporine unadjusted/adjusted per weight daily dose or serum levels were noted. CONCLUSIONS: Immunosuppression needs were increased for those patients treated with TAC but not cyclosporine. LT recipients prescribed TAC require close monitoring after treatment completion to avoid potential risk of acute rejection.