Citations

Background: Osteochondral allograft (OCA) transplantation is an important surgical technique for full-thickness chondral defects in the knee. For patients undergoing this procedure, topography matching between the donor and recipient sites is essential to limit premature wear of the OCA. Currently, there is no standardized process of donor and recipient graft matching. Purpose: To evaluate a novel topography matching technique for distal femoral condyle OCA transplantation using 3-dimensional (3D) laser scanning to create 3D-printed patient-specific instrumentation in a human cadaveric model. Study Design: Descriptive laboratory study. Methods: Human cadaveric distal femoral condyles (n = 12) underwent 3D laser scanning. An 18-mm circular osteochondral recipient defect was virtually created on the medial femoral condyle (MFC), and the position and orientation of the best topography-matched osteochondral graft from a paired donor lateral femoral condyle (LFC) were determined using an in silico analysis algorithm minimizing articular step-off distances between the edges of the graft and recipient defect. Distances between the entire surface of the OCA graft and the underneath surface of the MFC were evaluated as surface mismatch. Donor (LFC) and recipient (MFC) 3D-printed patient-specific guides were created based on 3D reconstructions of the scanned condyles. Through use of the guides, OCAs were harvested from the LFC and transplanted to the reamed recipient defect site (MFC). The post-OCA recipient condyles were laser scanned. The 360° articular step-off and cartilage topography mismatch were measured. Results: The mean cartilage step-off and graft surface mismatch for the in silico OCA transplant were 0.073 ± 0.029 mm (range, 0.005-0.113 mm) and 0.166 ± 0.039 mm (range, 0.120-0.243 mm), respectively. Comparatively, the cadaveric specimens postimplant had significantly larger step-off differences (0.173 ± 0.085 mm; range, 0.082-0.399 mm; P = .001) but equivalent graft surface topography matching (0.181 ± 0.080 mm; range, 0.087-0.396 mm; P = .678). All 12 OCA transplants had mean circumferential step-off differences less than a clinically significant cutoff of 0.5 mm. Conclusion: These findings suggest that the use of 3D-printed patient-specific guides for OCA transplantation has the ability to reliably optimize cartilage topography matching for LFC to MFC transplantation. This study demonstrated substantially lower step-off values compared with previous orthopaedic literature when also evaluating LFC to MFC transplantation. Using this novel technique in a model performing MFC to MFC transplantation has the potential to yield further enhanced results due to improved radii of curvature matching. Clinical Relevance: Topography-matched graft implantation for focal chondral defects of the knee in patients improves surface matching and has the potential to improve long-term outcomes. Efficient selection of the allograft also allows improved availability of the limited allograft sources.

Abstract Background Cardiac sarcoidosis (CS) is a granulomatous disease that can manifest as conduction defects, ventricular arrhythmias, and heart failure. The diagnosis of CS is inherently difficult due to variable presentations; as such, endomyocardial biopsy is often required but lacks sensitivity due to patchy myocardial involvement. Moreover, the diagnostic criteria of CS and arrhythmogenic cardiomyopathy overlap, particularly in right-side dominant or biventricular presentations, which further complicates an already challenging differential diagnosis. Case summary A 53-year-old man with no prior chronic medical conditions presented with ventricular tachycardia (VT) and heart failure with reduced ejection fraction. He was found to have biventricular cardiomyopathy and late gadolinium enhancement on cardiac magnetic resonance imaging, resulting in an initial diagnosis of arrhythmogenic cardiomyopathy. Implantable cardioverter-defibrillator was placed, but he was readmitted for recurrent VT 2 months later. Despite an aggressive VT therapy (combination of antiarrhythmic drugs, epicardial and endocardial ablation, and stellate ganglion block), he continued with refractory VT and developed cardiogenic shock. Extra-corporeal membrane oxygenation was initiated as a bridge to heart transplantation. Pathology of the explanted heart revealed the underlying disease to be CS. Discussion Cardiac sarcoidosis can mimic arrhythmogenic biventricular cardiomyopathy and may be difficult to distinguish by the proposed diagnostic criteria. High clinical suspicion and thorough investigation are necessary for an earlier diagnosis and initiation of treatment.

Abstract Background Fabry’s disease, an X-linked lysosomal storage disorder, shares cardiac manifestations with hypertrophic cardiomyopathy (HCM). We underscore the importance of considering Fabry’s disease as a differential diagnosis in HCM patients, highlighting genetic testing’s role in cardiomyopathy evaluation. Case summary Three male patients with left ventricular hypertrophy were initially diagnosed with HCM but were later found to have Fabry’s disease through genetic testing. Atypical features such as renal dysfunction and conduction abnormalities raised suspicion. Genetic testing confirmed diagnosis, guiding tailored management. Discussion Fabry’s disease poses diagnostic challenges due to its resemblance to HCM. Genetic testing enables precise diagnosis and personalized management, especially in cases with atypical presentations. Early recognition and intervention, facilitated by genetic testing, can improve patient outcomes in Fabry’s disease.

AbstractObjectiveThe first international consensus criteria for optic neuritis (ICON) were published in 2022. We applied these criteria to a prospective, global observational study of acute optic neuritis (ON).MethodsWe included 160 patients with a first‐ever acute ON suggestive of a demyelinating CNS disease from the Acute Optic Neuritis Network (ACON). We applied the 2022 ICON to all participants and subsequently adjusted the ICON by replacing a missing relative afferent pupillary defect (RAPD) or dyschromatopsia if magnetic resonance imaging pathology of the optical nerve plus optical coherence tomography abnormalities or certain biomarkers are present.ResultsAccording to the 2022 ICON, 80 (50%) patients were classified as definite ON, 12 (7%) patients were classified as possible ON, and 68 (43%) as not ON (NON). The main reasons for classification as NON were absent RAPD (52 patients, 76%) or dyschromatopsia (49 patients, 72%). Distribution of underlying ON etiologies was as follows: 78 (49%) patients had a single isolated ON, 41 (26%) patients were diagnosed with multiple sclerosis, 25 (16%) patients with myelin oligodendrocyte glycoprotein antibody‐associated disease, and 15 (9%) with neuromyelitis optica spectrum disorder. The application of the adjusted ON criteria yielded a higher proportion of patients classified as ON (126 patients, 79%).InterpretationAccording to the 2022 ICON, almost half of the included patients in ACON did not fulfill the requirements for classification of definite or possible ON, particularly due to missing RAPD and dyschromatopsia. Thorough RAPD examination and formal color vision testing are critical to the application of the 2022 ICON.

AbstractBackgroundThermal ablation has recently become a key therapy for the treatment of colorectal liver metastasis (CLM). However, the role of ablation in combination with resection has not yet been firmly established. We hypothesize that in patients with CLM, those who undergo liver resection with ablation (RA) have similar outcomes compared with those who undergo liver resection only.MethodsWe reviewed a multicenter international database of 906 surgical procedures for CLM from 5 high volume hepatobiliary surgical units. Patients undergoing RA (n = 63) were matched based on the number of lesions and tumor size using a 1:1 balanced propensity score analysis with those having resection only (n = 63). Our primary outcomes were overall survival (OS) and disease‐free survival (DFS).ResultsThe mean age of our cohort was 58 ± 11 years, with 43% females. With a median follow‐up of 70.8 months, patients in the resection and RA group had a median OS of 45.1 and 54.8 months (p = 0.71), respectively. The median DFS was 22.7 and 14.2 months (p = 0.045), respectively. Using a multivariate Cox proportional hazards regression model, the treatment approach was not associated with OS (p = 0.94) or DFS (p = 0.059). A higher number of lesions is independently associated with worse DFS (hazard ratio: 1.12, p < 0.01). When there was disease recurrence, the region of recurrence was similar between the RA versus resection only groups (p = 0.27), but there was a shorter time to recurrence in the RA group (p = 0.002).ConclusionFor CLM, the treatment approach was not significantly associated with OS or DFS, while tumor biology likely played an important role. Prospective research on the quality and effectiveness of thermal ablation combined with hepatic resection is warranted.

CMV-specific T cells, NK cells, and neutralizing antibodies (nAbs) were assessed in a randomized trial of CMV prevention with preemptive antiviral therapy (PET) versus prophylactic antiviral therapy (PRO) in donor-seropositive/recipient-seronegative (D + R – ) liver transplant recipients (LTxR) at 100 days (end of intervention) and at 6 and 12 months after transplant. The PET group had significantly increased numbers of circulating polyfunctional T cells, NK cells, and nAbs compared with the PRO group at day 100, and several CMV immune parameters remained significantly higher by 12 months after transplant. Among PET recipients, preceding CMV viremia (vs. no preceding viremia) was associated with significantly higher levels of most CMV immune parameters at day 100. Higher numbers of CMV-specific polyfunctional T cells and NKG2C + NK cells at day 100 were associated with a decreased incidence of CMV disease in multivariable Cox regression. The strongest associations with protection against CMV disease were with increased numbers of CMV-specific polyfunctional CD4 + T cells, CD3 neg CD56 dim CD57 neg NKG2C pos cells, and CD3 neg CD56 dim CD57 pos NKG2C pos NK cells. Our results suggest that PET is superior to PRO for CMV disease prevention by allowing low-level CMV replication and associated antigen exposure that is promptly controlled by antiviral therapy and facilitates enhanced CMV protective immunity in D + R – LTxR.

AbstractThis case describes a pediatric patient with a history of ichthyosis vulgaris and global anhidrosis who was diagnosed with erythema ab igne (EAI), a rare dermatosis resulting from chronic heat exposure. After developing progressive, reticulated brown patches on his extremities and abdomen, extensive diagnostic investigations were conducted to rule out autoimmune, vascular, and genetic etiologies. Bloodwork was unrevealing and biopsies showed histologic features closely resembling keratosis lichenoides chronica. Ultimately, after discovering the patient had prolonged exposure to a space heater, the diagnosis of EAI was made. This case underscores the diagnostic challenges in pediatric EAI cases and emphasizes the importance of careful history taking as part of a comprehensive evaluation.

Abstract Osteoporosis and other metabolic bone diseases are prevalent in the aging population. While bone has the capacity to regenerate throughout life, bone formation rates decline with age and contribute to reduced bone density and strength. Identifying mechanisms and pathways that increase bone accrual in adults could prevent fractures and accelerate healing. G protein-gated inwardly rectifying K+ (GIRK) channels are key effectors of G protein-coupled receptor signaling. Girk3 was recently shown to regulate endochondral ossification. Here, we demonstrate that deletion of Girk3 increases bone mass after 18 weeks of age. Male 24-week-old Girk3-/- mice have greater trabecular bone mineral density and bone volume fraction than wildtype (WT) mice. Osteoblast activity is moderately increased in 24-week-old Girk3-/- mice compared to WT mice. In vitro, Girk3-/- bone marrow stromal cells (BMSCs) are more proliferative than WT BMSCs. Calvarial osteoblasts and BMSCs from Girk3-/- mice are also more osteogenic than WT cells, with altered expression of genes that regulate the wingless-related integration site (Wnt) family. Wnt inhibition via Dickkopf-1 (Dkk1) or β-catenin inhibition via XAV939 prevents enhanced mineralization, but not proliferation, in Girk3-/- BMSCs and slows these processes in WT cells. Finally, selective ablation of Girk3 from cells expressing Cre recombinase from the 2.3 kb-Col1a1 promoter, including osteoblasts and osteocytes, is sufficient to increase bone mass and bone strength in male mice at 24 weeks of age. Taken together, these data demonstrate that Girk3 regulates progenitor cell proliferation, osteoblast differentiation, and bone mass accrual in adult male mice.

ABSTRACT Chronic nonbacterial osteomyelitis (CNO) is an uncommon autoinflammatory disorder. Significant effort has recently been spent to better define and treat this disorder including development of consensus treatment protocols, validate disease activity tools, and refining classification criteria. However, the underlying immunopathogenesis of the disease remains elusive. In this report, we describe the simultaneous onset of CNO in siblings. A pathogenic gene mutation was not identified, and these sisters lacked a similar biomarker profile. This report highlights that if a genetic predisposition for CNO exists, it may be related to complex polygenic or multifactorial mechanisms of disease evolution.