Comparing Clinical Outcomes and Knee Stability in Remnant- Preserving ACL Reconstruction Versus Standard ACL Reconstruction: A Systematic Review and Meta-analysis.

BACKGROUND: Anterior cruciate ligament reconstruction (ACLR) is one of the most frequently performed procedures in sports medicine, and undesirable outcomes still may range from 3-18%. One technique that has been explored to improve outcomes is preservation of the ACL remnant tibial stump, as opposed to stump debridement, at the time of reconstruction. PURPOSE: To review current high-level evidence and compare remnant-preserving anterior cruciate ligament reconstruction (ACLR) versus standard ACLR in terms of clinical outcomes and measures of knee stability. HYPOTHESIS: ACLR with remnant preservation would result in improved clinical outcomes and knee stability measures. STUDY DESIGN: Systematic review; Level of evidence, 2. METHODS: A systematic review of randomized controlled trials (RCTs) and cohort studies comparing remnant-preserving ACLR with standard ACLR with a minimum level of evidence of 2 was performed. Extracted data were summarized as general information, surgical characteristics, postoperative clinical outcomes, knee stability, graft evaluation, tunnel assessment, and postoperative complications. When feasible, a meta-analysis was performed. RESULTS: Seven RCTs and 5 cohort studies met the inclusion criteria. In total, 518 patients underwent remnant-preserving ACLR and 604 patients underwent standard ACLR. Ten studies performed the reconstruction with hamstring tendon (HT) autografts, 1 study with HT and bone-patellar tendon-bone autografts, and 1 study with HT and tibialis anterior allografts. On meta-analysis, remnant-preserving ACLR provided comparable outcomes with respect to International Knee Documentation Committee grades or Tegner scores. Even though there was a significant improvement in Lysholm scores (mean difference, -1.9; 95% CI, -2.89 to -0.91; P = .0002) with the remnant-preserving technique, this did not exceed previously reported minimal clinically important difference values. Remnant-preserving ACLR demonstrated superior knee stability in terms of patients achieving negative pivot shift when compared with the control group (88.89% vs 79.92%; P = .006). Although there was a significant improvement in the side-to-side difference in anterior tibial translation favoring remnant preservation (P = .004), the mean difference was 0.51 mm. CONCLUSION: Remnant-preserving ACLR, primarily with HT autografts, results in comparable clinical outcome scores and significantly improved knee stability relative to standard ACLR without remnant preservation without increasing the complication rate. Further studies will help clarify if remnant-preserving ACLR also has benefits in terms of enhancing graft integration and maturation, improving proprioception, limiting tunnel enlargement, and reducing complications.

Beta-lactam-resistant Staphylococcus aureus in spinal osteomyelitis and spondylodiscitis: current landscape in antibiotic resistance, treatment, and complications.

OBJECTIVE: Spinal osteomyelitis and spondylodiscitis (SD) are infections of the vertebral body and disc, respectively, with more than 50% associated with Staphylococcus aureus. Methicillin-resistant S. aureus (MRSA) has become a pathogen of interest in cases of SD due to increasing prevalence. The purpose of this investigation was to characterize the current epidemiological and microbiological landscape in SD cases, in addition to medical and surgical challenges in treating these infections. METHODS: The PearlDiver Mariner database was queried for ICD-10 codes to identify cases of SD from 2015 to 2021. The initial cohort was stratified by offending pathogens, including methicillin-sensitive S. aureus (MSSA) and MRSA. Primary outcome measures included epidemiological trends, demographics, and rates of surgical management. Secondary outcomes included length of hospital stay, rate of reoperation, and complications associated with surgical cases. Multivariable logistic regression was used to control for age, gender, region, and Charlson Comorbidity Index (CCI). RESULTS: Nine thousand nine hundred eighty-three patients met the inclusion criteria and were retained for this study. Approximately half (45.5%) of SD cases resulting from S. aureus infections each year were resistant to beta-lactam antibiotics. The proportion of cases that were managed surgically was 31.02%. Among the cases that involved surgical intervention, 21.83% underwent revision operations within 30 days of the original procedure and 37.29% of cases returned to the operating room within 1 year. Substance abuse, specifically alcohol, tobacco, and drug use, were strong predictors for surgical intervention in cases of SD (all p < 0.001), in addition to obesity (p = 0.002), liver disease (p < 0.001), and valvular disease (p = 0.025). After adjusting for age, gender, region, and CCI, cases of MRSA were more likely to undergo surgical management (OR 1.19, p = 0.003). MRSA SD also exhibited higher rates of reoperation within 6 months (OR 1.29, p = 0.001) and 1 year (OR 1.36, p < 0.001). Surgical cases resulting from MRSA infections also exhibited higher morbidity and significant rates of transfusion (OR 1.47, p = 0.030), acute kidney injury (OR 1.35, p = 0.001), pulmonary embolism (OR 1.44, p = 0.030), pneumonia (OR 1.49, p = 0.002), and urinary tract infection (OR 1.45, p = 0.002) compared with MSSA SD infections. CONCLUSIONS: More than 45% of cases of S. aureus SD in the US are resistant to beta-lactam antibiotics, presenting obstacles in treatment. Cases of MRSA SD are more likely to be managed surgically and have higher rates of complications and reoperations. Early detection and prompt operative management are imperative to reduce the risk of complications.

Hospitalization in maintenance peritoneal dialysis: a review.

Although hemodialysis continues to be the dominant form of dialysis in the United States, peritoneal dialysis rates continue to rise both nationally and worldwide. Peritoneal dialysis offers patients increased flexibility due to the ability to dialyze at home, leading to potential quality of life benefits for patients. However, questions exist regarding clinical outcomes in patients on peritoneal dialysis and the literature has not recently been reviewed. This review examines hospitalizations within patients utilizing peritoneal dialysis, including comparison to other dialysis modalities. Much heterogeneity exists within the literature, often explained by patient population. Recent data show all-cause, cardiovascular, and infection-related hospitalizations to be high in patients on peritoneal dialysis, although data variation limits conclusions in comparison to other modalities. This review found there is insufficient evidence to suggest admission rates are different in peritoneal dialysis than in-center hemodialysis. While the rate is similar to infectious causes, most studies report cardiovascular complications to be the leading cause of hospitalization. Some evidence suggests that cardiovascular hospitalizations occur at a higher rate in peritoneal dialysis, but further studies are required. The infection-related hospitalization rate appears to be higher in peritoneal dialysis due to rates of peritonitis, but rates of life-threatening bacteremia are lower. Differences in reporting of hospital days vs. length of stay challenge the interpretability of length of stay data between modalities, but patients on PD may spend more days per year in the hospital. In summary, hospitalization is highly prevalent in patients on peritoneal dialysis and few definitive conclusions can be drawn in comparison to other dialysis modalities. In eligible patient populations who desire increased flexibility, peritoneal dialysis is a reasonable modality choice.

Mutant IDH Inhibits IFNγ-TET2 Signaling to Promote Immunoevasion and Tumor Maintenance in Cholangiocarcinoma.

Isocitrate dehydrogenase 1 mutations (mIDH1) are common in cholangiocarcinoma. (R)-2-hydroxyglutarate generated by the mIDH1 enzyme inhibits multiple α-ketoglutarate-dependent enzymes, altering epigenetics and metabolism. Here, by developing mIDH1-driven genetically engineered mouse models, we show that mIDH1 supports cholangiocarcinoma tumor maintenance through an immunoevasion program centered on dual (R)-2-hydroxyglutarate-mediated mechanisms: suppression of CD8+ T-cell activity and tumor cell-autonomous inactivation of TET2 DNA demethylase. Pharmacologic mIDH1 inhibition stimulates CD8+ T-cell recruitment and interferon γ (IFNγ) expression and promotes TET2-dependent induction of IFNγ response genes in tumor cells. CD8+ T-cell depletion or tumor cell-specific ablation of TET2 or IFNγ receptor 1 causes treatment resistance. Whereas immune-checkpoint activation limits mIDH1 inhibitor efficacy, CTLA4 blockade overcomes immunosuppression, providing therapeutic synergy. The findings in this mouse model of cholangiocarcinoma demonstrate that immune function and the IFNγ-TET2 axis are essential for response to mIDH1 inhibition and suggest a novel strategy for potentiating efficacy. SIGNIFICANCE: Mutant IDH1 inhibition stimulates cytotoxic T-cell function and derepression of the DNA demethylating enzyme TET2, which is required for tumor cells to respond to IFNγ. The discovery of mechanisms of treatment efficacy and the identification of synergy by combined CTLA4 blockade provide the foundation for new therapeutic strategies. See related commentary by Zhu and Kwong, p. 604. This article is highlighted in the In This Issue feature, p. 587.