Citations

Abstract A posterior tibial slope (PTS) greater than 12° is an established risk factor for anterior cruciate ligament graft reconstruction failure. Reducing PTS is thus considered protective to the anterior cruciate ligament graft, and it can be achieved through an anterior closing‐wedge osteotomy. Prior to the procedure, PTS should be accurately measured to determine the amount of correction that is needed. Radiographic films remain the gold standard for measuring PTS. The purpose of this presentation is to show validated and reproducible step‐by‐step techniques for measuring PTS and anterior tibial translation for anterior closing‐wedge osteotomy using monopedal full‐length weight‐bearing tibia standing radiographs.

OBJECTIVES: Pneumocystis jirovecii pneumonia (PCP) can cause severe hypoxemic respiratory failure in immunocompromised patients. Contemporary outcomes of venovenous extracorporeal membrane oxygenation (VV ECMO) support for PCP are poorly characterized, and existing reports are limited to small case series. DESIGN: Retrospective cohort study. SETTING: International registry study using the Extracorporeal Life Support Organization (ELSO) registry. PATIENTS/SUBJECTS: Adults with PCP-associated hypoxemic respiratory failure supported with VV ECMO between 2011 and 2024. INTERVENTIONS: VV ECMO. MEASUREMENTS AND MAIN RESULTS: A total of 209 patients with PCP-associated respiratory failure supported with VV ECMO were identified. The overall in-hospital mortality was 60.8%. Survivors were younger than nonsurvivors (median age 41.9 vs. 46.8 yr; p = 0.047). Duration of mechanical ventilation before VV ECMO was longer among nonsurvivors (median 4.7 vs. 1.6 d; p = 0.019). The proportion of patients with HIV infection was similar among survivors and nonsurvivors (19.5% vs. 22.1%; p = 0.73). Pre-ECMO vasopressor use, prone positioning, and renal replacement therapy were common and did not differ between groups. Clinical course was characterized by prolonged VV ECMO support (median 18.6 d) and frequent complications, including pneumothorax (21.1%), renal replacement therapy during VV ECMO (31.6%), intracranial hemorrhage or stroke (7.7%), and major pulmonary or gastrointestinal hemorrhage (16.8%). PCP accounted for a small proportion of VV ECMO runs reported to the ELSO registry throughout the study period at 0.36% of reported cases. No significant temporal trend in mortality was observed. CONCLUSIONS: PCP-associated respiratory failure supported with VV ECMO is associated with substantial mortality and prolonged VV ECMO support. These findings provide contemporary benchmarks that may inform VV ECMO candidacy discussions and expectations in this challenging patient population.

Abstract The intestinal epithelium harbors a large population of microbiota-dependent CD8αβ + T cells whose antigen specificity and regulation are ill-defined. By identifying MHCIa-restricted TCRs and generating tetramers against the gut commensal Segmented Filamentous Bacteria, we demonstrate that a single commensal species drives a clonally expanded, antigen-specific CD8αβ + T cell within the intraepithelial lymphocyte compartment. Mechanistically, the intestinal epithelium coordinates coincident signals governing this population: peptide:MHC-dependent TCR engagement drives pIEL accumulation, while αvβ6-mediated TGFβ activation restraints effector cell differentiation. Perturbation of epithelial cell-mediated TGFβ activation diverts commensal-specific CD8 + T cells toward inflammatory differentiation states transcriptionally convergent with those observed in ulcerative colitis. The intestinal epithelium thus functions as a dual-signal organizer of commensal-specific CD8 + T cell responses, coupling differentiation to restraint through spatially coincident molecular cues.

Abstract Background Postoperative spinal implant infections (PSIIs) are a serious complication of instrumented spinal fusion. Although debridement with implant retention is standard for early infection, the optimal duration of antimicrobial therapy remains uncertain. Methods We conducted a multicenter retrospective cohort study across 10 US academic centers, including adults with early PSII (≤90 days after fusion surgery) from 2017 to 2021. We excluded patients who experienced treatment failure within 6 weeks of debridement. The primary outcome was treatment failure. Antibiotic therapy effect was analyzed as a time-varying exposure using adjusted Cox proportional hazards models. Secondary analyses included 12-week landmark and clone-censor-weighted models to compare durations ≤ 12 weeks versus >12 weeks. Results A total of 116 patients out of 499 (23.2%) experienced treatment failure during a median follow-up of 3.2 years. Among patients who remain failure-free 6 weeks from debridement, being on antibiotics was not associated with treatment failure (adjusted hazard ratio [aHR] 0.71; 95% CI .48–1.07; P = .10). In a 12-week landmark analysis limited to 359 patients who were not on indefinite suppressive antibiotic therapy, treatment durations > 12 weeks did not significantly reduce the risk of failure (aHR 1.01; 95% CI .62–1.64; P = .99). Results were consistent in the clone-censor-weight sensitivity analysis (aHR 0.85; 95% CI .62–1.16; P = .30). Conclusions Prolonged antibiotic therapy was not associated with improved outcomes in early PSII managed with debridement and implant retention. These results support shorter, individualized antibiotic courses in patients with adequate surgical source control.

Abstract Background Osteoarthritis is a leading cause of disability worldwide, and cell‐based treatments including adipose‐derived and bone marrow aspirate have been sought by the lay and medical community as treatment options. Objective To perform a scoping review of published literature on cell‐based injections allowed by the U.S. Food and Drug Administration for the treatment of osteoarthritis to synthesize existing evidence and identify research gaps for future evaluation. Methods A comprehensive search of five databases was executed from inception through January 2, 2025. Studies that met the inclusion criteria were original research studies written in English on Food and Drug Administration‐allowed cell‐based treatments in adults with osteoarthritis of any joint. Results The database search yielded 4257 unique records. After screening, 84 studies met the inclusion criteria, encompassing 9996 patients and a total of 10,508 procedures. The primary research study designs were cohort studies ( n = 62), focused on treatment of knee osteoarthritis ( n = 63), and described bone marrow aspirate ( n = 42) and adipose‐derived ( n = 42) treatments. Postprocedure monitoring ranged from 6 weeks to 5 years, with most studies ≤1 year ( n = 59). Patient‐reported outcomes were reported in 83 of 84 studies; few provided imaging outcomes including magnetic resonance imaging ( n = 9) or radiographs ( n = 2). Conclusion This review identified limited randomized controlled trials, limited studies outside the knee, limited description of cell‐based treatments, and treatment protocols, along with inconsistent patient‐reported outcomes limited to 1 year in most studies. We propose establishing reporting guidelines in research on cell‐based therapies.

Abstract Purpose: Circulating tumor fraction estimate (ctFE) is a machine learning–derived composite metric of circulating tumor DNA (ctDNA) burden. We hypothesized that pre-treatment and early on-treatment ctFE could robustly risk-stratify patients with locally advanced (LA) and oligometastatic non–small cell lung cancer (NSCLC) treated with radiotherapy (RT). Experimental Design: In a prospective phase II clinical trial (NCT03916419), 26 patients with unresectable stage IIB to IIIC NSCLC received magnetic resonance (MR)-guided hypofractionated chemoradiotherapy (chemoRT) followed by immunotherapy. Plasma ctDNA was profiled at baseline and mid-treatment (days 10–14) to derive ctFE and maximum variant allele frequency (Max VAF). A burden-based ctFE threshold derived from baseline samples was applied unchanged to mid-treatment samples and validated in two external cohorts: LA NSCLC treated with chemoRT (LA-RW; n = 94) and oligometastatic NSCLC treated with RT (OM-RW; n = 309). Results: Pre- and mid-treatment ctFE burden strongly stratified overall survival (OS) and progression-free survival (PFS), outperforming Max VAF and ctFE detectability. The baseline ctFE was prognostic for OS (HR 5.93, P = 0.005) and PFS (HR 11.08, P < 0.001) and remained significant at mid-treatment (OS: HR 7.08; PFS: HR 12.06; both P < 0.001). Early ctFE dynamics defined three molecular response groups with OS separation (median OS 60.8 vs. 13.0 vs. 2.9 months; P < 0.001). ctFE remained associated with survival in both validation cohorts. Conclusions: Early ctFE derived from a clinically available, tumor-naïve ctDNA assay enables noninvasive risk stratification in LA and oligometastatic NSCLC treated with RT, supporting its use as a practical biomarker for precision treatment adaptation.

Abstract Tunnel convergence in multiligament knee surgery remains a technical challenge. Anterior cruciate ligament (ACL) femoral sockets/tunnels and lateral collateral ligament (LCL) femoral sockets/tunnels during anatomic posterolateral corner (PLC) reconstructions are particularly vulnerable to convergence. This is secondary to the limited amount of bony real estate available on the lateral distal femur. Previous studies have attempted to define a specific angle to direct the LCL tunnel away from the ACL tunnel. However, inconsistency with ACL femoral socket creation and variability in bony architecture can make this strategy unreliable. This surgical technique describes how to minimize the risk of ACL and LCL tunnel convergence during ACL and PLC reconstructions.

Hip arthroscopy is an increasingly common procedure to treat intra‐articular conditions such as labral tears and femoroacetabular impingement. With the increase in frequency of such procedures, so too are revision arthroscopic hip procedures. Capsular repair in the setting of revision hip arthroscopy can be challenging due to the presence of adhesions and scar tissue formation that obscure tissue planes, suboptimal quality of residual capsular tissue, and the presence of capsular tissue defects. This technical note aims to describe the key surgical principles and considerations of revision hip capsular closure.

Abstract Background Presacral tumours are rare and heterogeneous lesions arising within a complex anatomical space, resulting in variability in diagnosis and management. Increasing incidental detection and evolving surgical and oncological strategies have highlighted the need for contemporary guidance. The aim of this study was to establish an international expert consensus on the optimal diagnosis and management of presacral tumours. Methods An international panel of colorectal surgeons from high-volume units was convened. Evidence- and practice-based statements were developed after domain-based literature reviews and refined through five online and two in-person meetings. Consensus was achieved using a modified Delphi process with anonymous voting. Results In total, 16 colorectal surgeons participated in the study. Ten domains were identified resulting in the development of 22 statements based on expert opinion and retrospective studies. After two rounds, unanimous (100%) agreement was achieved for all statements. High-resolution MRI with structured synoptic reporting is endorsed as central to risk stratification. Selective image-guided transperineal or parasacral biopsy is recommended for high-risk lesions where histology would alter management. Complete surgical resection is defined as the operative goal, with approach tailored to tumour biology and anatomy; minimally invasive surgery is considered appropriate in selected cases. Non-operative surveillance is supported for carefully selected asymptomatic, low-risk cystic lesions. Postoperative surveillance is recommended in a risk-adapted manner according to histopathology and margin status. Conclusion This international consensus provides a pragmatic, risk-stratified framework for the multidisciplinary diagnosis and management of presacral tumours. These recommendations aim to reduce practice variation, support decision-making in specialized centres, and inform future prospective collaborative research.