Abstract The Fracture Nonunion Symposium presented at the 2024 Orthopaedic Trauma Association Basic Science Focus Forum featured invited speakers who discussed current perspectives on this topic. Clinical approaches, diagnostic advancements, basic science perspectives, and novel treatment strategies were discussed. This symposium was curated to highlight this common and challenging clinical problem faced by orthopaedic and musculoskeletal practitioners from around the globe.
Primary Lateral Sclerosis Natural History Study:
Primary Lateral Sclerosis Functional Rating Scale
and Other Outcomes Assessment
Objective The primary lateral sclerosis ( PLS ) consensus diagnostic criteria and functional rating scale ( PLSFRS ) were recently established to facilitate and optimize future PLS clinical trials. We examined the trajectory of the PLSFRS and other functional outcome measures and biomarkers in the PLS Natural History Study ( PLS NHS ) to understand their performance in this prospective cohort. Methods The PLS NHS is a prospective, longitudinal, multicenter study of people living with PLS in different diagnostic categories: early (disease duration <2 years); probable (2–4 years); and definite PLS (4–15 years). PLSFRS scores and other functional outcome measures were collected at baseline, 3‐, 6‐, 9‐, and 12‐month follow‐up visits. Baseline characteristics were compared between the groups. The slopes of the PLSFRS and other functional outcome measures over 12 months were examined in the overall cohort and subgroups using linear mixed‐effect models. The associations between baseline characteristics and the rate of PLSFRS decline were analyzed with linear regression models. Results A total of 76 participants were included: early (n = 6); probable (n = 26); and definite (n = 44) PLS . Baseline PLSFRS total scores were highest in the early PLS group, followed by the probable and definite PLS groups. In the overall cohort, the PLSFRS total score declined by 0.33 points/month (95% confidence interval [0.27–0.39], adjusted p < 0.05). The rate of decline was steepest in the early PLS group, followed by the probable and definite PLS groups. Baseline neurofilament light chain level was associated with the rate of PLSFRS decline over 1 year ( p = 0.001). Interpretation In PLS, the rate of functional decline, as measured by the PLSFRS total score, is faster during the early phase of the disease. Neurofilament light might serve as a prognostic biomarker in PLS. ANN NEUROL 2026;99:418–428
Poster 149: Traumatic Lateral Femoral Condyle Lesions associated with Patellofemoral Instability Demonstrate Excellent Outcomes With Non-Operative Management and Patellar Stabilization with Meniscal Coverage at 8-Years Follow-Up
Objectives: Traumatic lateral patellar dislocation is frequently associated with cartilage lesions, particularly of the patella and lateral femoral condyle (LFC). Multiple treatment options to address these chondral lesions including debridement, microfracture, cartilage restoration with allo- or autograft, and osteotomies can be utilized at the index patellar stabilization surgery, or in a staged fashion. However, these additional procedures are not without increased morbidity and long-term benefit has not been well elucidated. In patients with traumatic chondral lesions associated with patellofemoral instability (PFI), meniscal coverage of the lesion and intervention to eliminate further patellar instability may be all that is required for a successful outcome. Thus rendering the increased time, morbidity, and cost of chondral procedures unjustified in this setting. The purpose of this study was to assess outcomes of patients with LFC chondral lesions after traumatic patellar dislocations and whether meniscus coverage of the lesion on magnetic resonance imaging (MRI) has an impact on patient outcomes. Methods: A retrospective chart review was performed to compare outcomes for patients with LFC lesions following acute patellar dislocation treated surgically at a single institution. MRI, operative reports, and intraoperative imaging were reviewed to assess for LFC lesions. Size of the LFC lesion and evaluation of meniscus coverage was measured in the coronal plane on T2 MRI sequences (Figure 1). Patient charts were reviewed to follow postoperative rehabilitation and clinical course. Patient reported outcome measures (PROMs) were obtained using the International Knee Documentation Committee (IKDC) score, Lysholm Knee score, Visual Analog Scale (VAS), and Tegner Activity score. Results: A total of 228 patients underwent surgical stabilization for patellar instability from 2001 to 2022, 81 of which had an LFC lesion identified on MRI and confirmed intraoperatively. Seven of these patients underwent a concomitant cartilage restoration procedure (3 internal fixation of osteochondral fragment, 2 microfracture, 1 osteochondral allograft, and 1 MACI) and they were excluded from the study leaving 74 patients. In assessing meniscus coverage of the chondral lesion, 10 of these lesions had no meniscus coverage, 8 had 1-50% coverage, and 56 had 51-100% coverage. The average size of the chondral lesion was 7.1 ± 2.9 mm and the majority were in the anterior one-third of the LFC. Average follow up from the index surgery was 7.6 years (range, 2.2-15.2 years). During this time frame, 12 patients had subsequent knee surgeries, none of which were to address the LFC lesion (Table 2). Postoperatively, nearly all patients reported improvement in their pain with an average VAS pain decrease of 3.7 points. There were no significant differences in PROMs in patients with meniscus coverage versus those without (Table 2). At the time of final follow-up, four patients had radiographic evidence of knee osteoarthritis (OA) within the lateral compartment, and one underwent a total knee arthroplasty (TKA). The patient that underwent a TKA had no meniscal coverage of their chondral lesion at the time of their index procedure. Conclusions: Cartilage lesions secondary to traumatic lateral patellar dislocation are common; however, appropriate management of these lesions remains unclear. The present findings suggest that not surgically addressing chondral lesions in patients with overlying meniscus coverage can allow for high functional outcomes and minimal pain after patellar stabilization procedures. Although only four patients progressed to radiographic evidence of OA, long term data will be valuable to understand whether overlying meniscus coverage is also protective against the development of OA and progression to TKA.
Consensus practice guidelines on sacroiliac joint complex pain from a multispecialty, international working group
Abstract Background The past two decades have witnessed tremendous growth in the appreciation and treatment of sacroiliac joint (SIJ) complex pain, including anatomical dissections that shed light on innervation, an appreciation for the contribution of extra-articular components to SIJ complex pain, the advent of radiofrequency ablation (RFA) and a host of minimally invasive surgical techniques. Yet, there is no standardization on diagnosis and treatment paradigms. Methods In February 2023, the Boards of Directors for the American Academy of Pain Medicine (AAPM) and American Society of Regional Anesthesia & Pain Medicine (ASRA-PM) approved the development of multispecialty guidelines on SIJ complex pain. Thirty partner organizations with clinical and scientific interests in SIJ complex pain were identified, and formal letters of request-for-participation were sent to each, along with a request for nominees to serve on the committee. Twenty five organizations agreed to participate in addition to the Departments of Defense and Veterans Affairs. A steering committee developed 21 questions, which spanned criteria for diagnosis, non-interventional and interventional treatments including surgery, technical parameters on how to optimize results, and what constitutes positive outcomes. Questions were methodically assigned to specialized modules comprising 4-5 members with complementary expertise, who collaborated with the Subcommittee Lead and one of three Committee Chairs to develop preliminary drafts. Following thorough revisions, these drafts were subsequently submitted to the full committee for comprehensive review. A modified Delphi method was used in which the answers to questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was achieved. During a committee meeting before commencement, it was agreed that recommendations would be noted when there was >50% agreement among committee members, but that a formal recommendation would require ≥75% consensus. Results Twenty-one organizations formally endorsed the guidelines. The American Society of Anesthesiologists, and American Academy of Physical Medicine & Rehabilitation, and the North American Spine Society affirmed the benefit of the guidelines but did not officially endorse them. The American Academy of Neurology declined to affirm the benefit of the guidelines citing “lack of relevance to their membership.” Per policies, while the Departments of Defense and Veterans Affairs did not formally review the guidelines for endorsement, their representatives approved them. In addition to being endorsed or the benefit affirmed by all voting organizations, complete consensus from committee members was obtained on all 21 questions. On 2 recommendations, there were dissensions from 3 societies who thought that selecting patients for sacral lateral branch RFA and minimally invasive fusion should be based on ≥75% relief from 2 blocks instead of at least 50% relief from a single block before RFA, and greater than 50% pain relief with documented functional improvement after a single block before fusion. One additional society (Latin American Society of Regional Anesthesia) abstained on the statement that the evidence is stronger for extra-articular than intra-articular injections. The committee found that a battery of physical exam tests has reasonable sensitivity, but lower specificity, for identifying intra-articular but not extra-articular pathology, with negative tests having greater predictive value than positive ones. Intra-articular injections have diagnostic validity for SIJ intra-articular, but not extra-articular pain. There is unclear or negative evidence for imaging. The prevalence rates of intra-articular and extra-articular pathology are comparable, with both intra- and extra-articular steroid injections providing at least 4 weeks of relief in well-selected patients. However, the evidence is slightly stronger for extra-articular corticosteroid injections to provide short-term relief. The evidence base for non-interventional therapies is indirect, extrapolated mostly from low back pain studies. There is weak evidence supporting dextrose-based prolotherapy and platelet-rich plasma to provide at least 3 months of pain relief. There is strong evidence for sacral lateral branch RFA to provide relief for at least 6 months in individuals with extra-articular pathology, with face validity and indirect evidence from randomized trials supporting sacral lateral branch blocks as a prognostic tool. There is stronger evidence for larger lesions or more aggressive lesioning strategies than for less stringent techniques. There is weak evidence to support non-steroidal anti-inflammatory drugs to prevent neuritis after RFA, and in most cases anticoagulation does not require cessation in the periprocedural perioid. With an aggressive lesioning strategy, sensory stimulation provides minimal therapeutic benefit, with weak, extrapolated evidence that motor stimulation can provide safety benefit. The cutoff to designate diagnostic or prognostic blocks as positive is most commonly set at 50%, with higher values not shown to improve outcomes for more definitive procedures; for therapeutic treatment outcomes, the evidence supports a lower threshold of ≥30% pain relief or meaningful benefit on non-pain outcomes (eg, opioid cessation) for designation of a positive response. For carefully selected patients with intra-articular SIJ complex pain based on controlled blocks who have failed conservative therapies, there is weak or very weak evidence that minimally invasive SIJ fusion can provide benefit for at least one year. Conclusions SIJ complex pain remains an underappreciated source of chronic low back pain, affecting between 15% and 30% of patients with axial pain predominantly below L5. Answers to many questions were limited by low-quality evidence, indicating the need for better research. SIJ complex pain is a multifarious condition (ie, pain can be from different portions of both the intra- and extra-articular components of the joint) for which an interdisciplinary, multimodal treatment plan can optimize treatment outcomes.
Evolution of Potentially Actionable Genomic Alterations in Advanced Prostate Cancer: A Real-World Analysis of Serial Circulating Tumor DNA Testing
Background: Longitudinal genomic profiling through serial circulating tumor DNA (ctDNA) testing offers a noninvasive method to monitor clonal evolution in advanced prostate cancer. This study evaluated the frequency and nature of newly emergent and potentially actionable genomic alterations detected through serial testing in a real-world setting. Methods: We conducted a retrospective analysis of advanced prostate cancer patients who underwent multiple Guardant360 ctDNA tests between October 2020 and March 2023. The study focused on identifying new genomic alterations absent in the initial test, with particular attention to alterations relevant for on-label therapies, therapies approved in other oncologic indications (i.e., off-label), or a clinical trial. Results: Among 479 patients with at least two ctDNA tests, the median interval between the first and second evaluable tests was 207 days. New and potentially actionable alterations emerged in 57.8% of patients, including potential targets for on-label therapies (16.7%), off-label therapies (16.5%), and clinical trials (55.7%). Tumor mutational burden (TMB) increased from “low” to “high” in 11% of patients, although none had microsatellite instability or mismatch repair deficiency. In a Mayo Clinic subset, ten patients received olaparib based on treatment-emergent alterations, but none achieved a prostate-specific antigen (PSA) response. Two patients who transitioned from low to high TMB received pembrolizumab, both with progressive disease as best response. Conclusions: In a large real-world cohort, serial ctDNA testing frequently identified new alterations that were not detected at baseline and are potentially actionable therapeutic targets, highlighting the value of serial genomic profiling for capturing clonal dynamics. Additional research is needed to better establish a framework for retesting and to clarify how these results should influence subsequent treatment decisions.
Neurodevelopment and neural environment inform Alzheimer's disease age at onset and phenotype
Abstract INTRODUCTION Risk factors associated with sporadic non‐amnestic and early‐onset Alzheimer's disease (AD) remain underexamined. METHODS We investigated a large, clinically heterogeneous, AD cohort for frequencies of established risk factors (hypertension, hypercholesterolemia, diabetes mellitus) alongside novel factors (non–right‐handedness, learning disability, seizures, autoimmune disease). RESULTS Early‐onset AD possessed lower frequencies of established risk factors (hypertension, hypercholesterolemia, diabetes mellitus, all p < 0.001) and higher frequencies of novel factors (non–right‐handedness, learning disability, active seizure, all p < 0.001; remote seizure, p = 0.002; and autoimmune disease, p = 0.007). An age at onset < 70 maximally distinguished novel from typical factors. Principal component analysis loaded novel factors into two components, non–right‐handedness and learning disability versus seizure and autoimmune disease, which combined, resulted in an exponential decrease in age at onset from one factor alone. DISCUSSION Identifying novel factors enriched in early‐onset and non‐amnestic AD introduces new theories of AD susceptibility and phenotypic heterogeneity, with significant implications for disease prediction and treatment. Highlights We identified a suite of novel factors overrepresented in early‐onset and non‐amnestic AD. These factors can be broadly conceptualized as neurodevelopmental (non–right‐handedness and learning disability) and neural environmental (seizure and autoimmunity). The combination of these factors produced exponential decreases in AD age at onset, compared to each alone, supporting a new theoretical framework for understanding AD risk with implications for disease prediction, prevention, and therapeutic intervention.
A Neurosurgeon's Guide to Mobile Health Application Development With a Case Study for Cervical Myelopathy
The integration of mobile health (mHealth) technologies is transforming neurosurgery. Despite its potential, many uses remain unrealized due to the unique challenges and complexity of developing mHealth technology. While neurosurgeons bring invaluable clinical expertise and an understanding of patient needs, the technical intricacies of application development often require collaboration with developers and computer scientists, a process that can feel unfamiliar and difficult to navigate. The aim of this article was to demystify mHealth development by providing a guide for neurosurgeons seeking to develop disease-specific mHealth applications. We outline this process using the development of SynapTrack, an mHealth tool designed to provide objective assessments of degenerative cervical myelopathy, a chronic condition caused by symptomatic compression of the cervical spinal cord. This article offers neurosurgeons concrete guidance on navigating key considerations such as design decisions, algorithm integration, database architecture, and data security. By grounding these insights with SynapTrack, this guide offers a transparent view into the development process and provides a practical framework that can be adapted to the development of other mHealth tools. The aim of this work was to foster interdisciplinary collaboration and enable neurosurgeons to develop mHealth applications tailored to the specific needs of their specialty.
Sulcal morphology in former American football players
Abstract Repetitive head impacts are associated with structural brain changes and an increased risk for chronic traumatic encephalopathy, a progressive neurodegenerative disease that can only be diagnosed after death. Chronic traumatic encephalopathy is defined by the abnormal accumulation of phosphorylated tau protein, particularly at the depths of the superior frontal sulci, suggesting that sulcal morphology may serve as a relevant structural biomarker. Contact sport athletes, such as former football players, are at elevated risk due to their prolonged exposure to repetitive head impacts. Cortical atrophy linked to underlying tau accumulation may result in shallower and wider sulci, potentially making sulcal morphology an imaging marker for identifying individuals at risk for this disease. This study investigated sulcal morphological differences in former football players and examined associations with age, football-related exposure, clinical diagnosis of traumatic encephalopathy syndrome, levels of certainty for chronic traumatic encephalopathy pathology, neuropsychological performance, and positron emission tomography imaging using flortaucipir. We analysed structural magnetic resonance imaging data from 169 male former football players (mean age 57.2 (8.2) years, range 45–74) and 54 age-matched, unexposed asymptomatic male controls (mean age 59.4 (8.5) years, range 45–74). Sulcal depth and width were quantified using the CalcSulc, focusing on two regions in each hemisphere commonly affected by chronic traumatic encephalopathy pathology: the superior frontal and occipitotemporal sulci. Generalized least squares models were used to assess group differences and interactions with age and football exposure variables, including age of first exposure, total years played, and cumulative head impact exposure. An analysis of covariance evaluated relationships between sulcal morphology, clinical measures, and flortaucipir uptake, adjusting for age, race, body mass index, education, imaging site, apolipoprotein E4 status, and total intracranial volume. Former football players demonstrated significantly shallower sulcal depth in the left superior frontal sulcus compared to unexposed controls. Earlier age of first exposure and longer football careers were associated with greater widening of the left occipitotemporal sulcus. Higher cumulative head impact exposure was linked to reduced sulcal depth in the left superior frontal region. However, sulcal morphology was not associated with clinical diagnosis, levels of certainty, neuropsychological test performance, or flortaucipir imaging. These findings suggest that sulcal morphology may reflect cumulative exposure to repetitive head impacts, particularly in brain regions vulnerable to chronic traumatic encephalopathy pathology. Future ante- and post-mortem validation studies are needed to determine whether sulcal morphology can serve as a reliable in vivo biomarker of risk.
Characteristics of Transfusion and Association With Oncologic Outcomes in Hepatoblastoma Resection
ABSTRACT Introduction Children with hepatoblastoma (HB) and other solid tumors frequently undergo intraoperative blood transfusion (IBT) with unknown impact on oncologic outcomes and scant data to guide transfusion in this population. This study tested the hypothesis that IBT is associated with poorer survival in children with HB. Methods A multicenter retrospective observational study of patients aged <18 years with HB who underwent primary tumor resection, including liver transplantation, from 2010 to 2019 was performed at 19 institutions. The association of IBT with risk of recurrence and death were determined using propensity score reweighted (PSR) Cox proportional hazards regression analyses. Results There were 338 patients identified who met inclusion criteria and had sufficient data for inclusion. Of those, 257 (76%) received IBT, including 253 (98%) who received packed red blood cells (pRBC), 84 (33%) who received plasma, and 28 (11%) who received platelets. IBT was associated with higher pretreatment extent of disease ( p < 0.001), presence of annotation factors (+VPEFR: 50%, n = 129 vs. 37%, n = 30, p = 0.035), and complex resections (extended, meso‐, or total hepatectomy: 54%, n = 139 vs. 27%, n = 22, p < 0.001); these differences were mitigated after applying propensity score weighting. Patients who received IBT had greater postoperative hemoglobin (g/dL) (median 10 (I8–11) vs. 9 (8–10), p = 0.013) and required more postoperative plasma and platelet transfusions ( p < 0.05). Median follow‐up was 4.4 (2.0–8.3) years. Compared with non‐IBT patients, those with IBT had higher incidence of death (PSR HR 2.35, 95% CI 1.10–5.02). Recurrence did not significantly differ across groups (PSR HR = 0.82, 95% CI 0.45–1.48). Conclusion IBT was associated with greater hazard of death. Postoperative hemoglobin levels suggested that unnecessary transfusions occurred and a pRBC‐focused approach to IBT led to coagulopathy. Development of optimal transfusion strategies for HB are needed to minimize unnecessary transfusions.
Caregiver experiences after the death of a person with dementia with Lewy bodies: A mixed-methods analysis
Background Dementia with Lewy bodies (DLB) is a common degenerative dementia, but no studies investigate bereaved caregiver experiences. Objective To investigate the experiences of caregivers three months after the death of persons with DLB using a mixed-methods approach. Methods Dyads of individuals with moderate-advanced DLB and their primary informal caregivers were followed prospectively every 6 months until the person with DLB died. Caregivers completed a study visit with questionnaires and a semi-structured interview ∼3 months later. Spearman correlation coefficients and Wilcoxon rank-sum tests evaluated the relationships of post-death measures with pre-death patient and caregiver variables. Thematic analysis was used to analyze the interviews. Results Seventy-three caregivers completed visits (mean 3.5 months post-death). Most of the caregivers were women (82.2%) and spouses (76.7%) or adult children (17.8%). Over 40% had scores indicating risk for clinical depression. Post-death caregiver experiences (depression, quality of life, grief, resilience) correlated with pre-death caregiver experiences. Post-death experiences did not associate with patient characteristics, disease-related symptoms, or healthcare services used in the last 6 months of life. Trajectories for caregiver measures from pre- to post-death visits varied widely. Interview themes included grief and sadness, anger, guilt and regret, relief, appreciation/gratitude, and adjusting to a new normal. Conclusions The finding that pre-death caregiving experiences have the strongest association with post-death experiences emphasizes the critical importance of accessible and evidence-based caregiver support before and after the death of a person with DLB. Research is needed to develop interventions for current and bereaved caregivers of individuals with DLB. Trial registration information NCT04829656 (submitted 2021-03-22).