Metabolic phenotypes reflect patient sex and injury status: A cross-sectional analysis of human synovial fluid.

OBJECTIVE: Osteoarthritis is a heterogeneous disease. The objective was to compare differences in underlying cellular mechanisms and endogenous repair pathways between synovial fluid (SF) from male and female participants with different injuries to improve the current understanding of the pathophysiology of downstream post-traumatic osteoarthritis (PTOA). DESIGN: SF from n = 33 knee arthroscopy patients between 18 and 70 years with no prior knee injuries was obtained pre-procedure and injury pathology assigned post-procedure. SF was extracted and analyzed via liquid chromatography-mass spectrometry metabolomic profiling to examine differences in metabolism between injury pathologies (ligament, meniscal, and combined ligament and meniscal) and patient sex. Samples were pooled and underwent secondary fragmentation to identify metabolites. RESULTS: Different knee injuries uniquely altered SF metabolites and downstream pathways including amino acid, lipid, and inflammatory-associated metabolic pathways. Notably, sexual dimorphic metabolic phenotypes were examined between males and females and within injury pathology. Cervonyl carnitine and other identified metabolites differed in concentrations between sexes. CONCLUSIONS: These results suggest that different injuries and patient sex are associated with distinct metabolic phenotypes. Considering these phenotypic associations, a greater understanding of metabolic mechanisms associated with specific injuries, sex, and PTOA development may yield data regarding how endogenous repair pathways differ between male and female injury types. Ongoing metabolomic analysis of SF in injured male and female patients can be performed to monitor PTOA development and progression.

Metabolomic Phenotypes Reflect Patient Sex and Injury Status: A Cross-Sectional Analysis of Human Synovial Fluid.

Background: Post-traumatic osteoarthritis (PTOA) is caused by knee injuries like anterior cruciate ligament (ACL) injuries. Often, ACL injuries are accompanied by damage to other tissues and structures within the knee including the meniscus. Both are known to cause PTOA but underlying cellular mechanisms driving disease remain unknown. Aside from injury, patient sex is a prevalent risk factor associated with PTOA. Hypothesis: Metabolic phenotypes of synovial fluid that differ by knee injury pathology and participant sex will be distinct from each other. Study Design: A cross-sectional study. Methods: Synovial fluid from n=33 knee arthroscopy patients between 18 and 70 years with no prior knee injuries was obtained pre-procedure and injury pathology assigned post-procedure. Synovial fluid was extracted and analyzed via liquid chromatography mass spectrometry metabolomic profiling to examine differences in metabolism between injury pathologies and participant sex. Additionally, samples were pooled and underwent fragmentation to identify metabolites. Results: Metabolite profiles revealed that injury pathology phenotypes were distinct from each other where differences in endogenous repair pathways that are triggered post-injury were detected. Specifically, acute differences in metabolism mapped to amino acid metabolism, lipid-related oxidative metabolism, and inflammatory-associated pathways. Lastly, sexual dimorphic metabolic phenotypes were examined between male and female participants, and within injury pathology. Specifically, Cervonyl Carnitine and other identified metabolites differed in concentration between sexes. Conclusions: The results of this study suggest that different injuries (e.g., ligament vs. meniscus), as well as sex are associated with distinct metabolic phenotypes. Considering these phenotypic associations, a greater understanding of metabolic mechanisms associated with specific injuries and PTOA development may yield data regarding how endogenous repair pathways differ between injury types. Furthermore, ongoing metabolomic analysis of synovial fluid in injured male and female patients can be performed to monitor PTOA development and progression. Clinical Relevance: Extension of this work may potentially lead to the identification of biomarkers as well as drug targets that slow, stop, or reverse PTOA progression based on injury type and patient sex.

Benefits of Implementing an Enhanced Recovery After Surgery Protocol in Ambulatory Surgery.

Background: Enhanced recovery after surgery (ERAS) protocols in orthopaedic surgery have garnered significant focus due to their ability to control pain adequately in the immediate postoperative window, allowing for earlier mobilization, shorter hospital stays, and fewer complications. Virginia Commonwealth University created a multimodal pain management approach in which patients receive a preoperative femoral nerve block followed by periarticular intraoperative local injection anesthesia consisting of bupivacaine, ketamine, and ketorolac. Hypothesis: We hypothesized that implementation of the ERAS protocol will decrease postoperative pain scores, decrease recovery time in the postanesthesia care unit (PACU), and decrease opioid use in anterior cruciate ligament (ACL) reconstruction. Study Design: Cohort study; Level of evidence, 3. Methods: Two patient cohorts were involved: before ERAS implementation (pre-ERAS) and after (post-ERAS). Patients with ACL reconstruction only and patients with ACL reconstruction with meniscal repair were analyzed separately. Post-ERAS patients received an intraoperative periarticular injection of bupivacaine, ketamine, and ketorolac and a postoperative multimodal pain regimen. Outcomes included time spent in the PACU, short-term and long-term opioid consumption, and pain score at discharge from the PACU. Results: Compared with pre-ERAS patients, post-ERAS patients had decreased pain (2.1 vs 0.84 out of 10, respectively), spent less time in the PACU (79.4 vs 62.8 minutes, respectively), and had less opioid consumption in the immediate postoperative period (4.55 vs 2.26 total morphine milligram equivalents [MMEs], respectively) (P < .001 for all). After ERAS implementation, long-term MME use decreased from 410 to 321 between 0 and 2 weeks postoperatively, 92.6 to 1.69 between 2 and 6 weeks, and 494.5 to 323 between 0 and 6 weeks (P < .001 for all). All domains showed significant improvements for both the ACL and the ACL plus meniscal repair cohorts, with the exception of pain at discharge in the ACL plus meniscal repair group. Conclusion: The study findings suggest that an enhanced recovery pathways protocol that includes a standardized intraoperative periarticular bupivacaine, ketamine, and ketorolac injection improves pain scores in the immediate postoperative window, decreases opioid consumption, and reduces recovery time in the PACU for patients undergoing ACL reconstruction.

Prosthetic Joint Infection due to Histoplasma capsulatum in a Patient from Trinidad: Workup, Pathology, and Treatment.

Histoplasma capsulatum is a rarely reported cause of prosthetic joint infections. This current case report is of a patient from Trinidad, with a history of a right total knee replacement (TKR), who underwent a successful two-stage revision due to a Histoplasmosis capsulatum periprosthetic joint infection (PJI). This case report offers a unique treatment plan to successfully treat Histoplasmosis capsulatum periprosthetic joint infections and emphasizes the importance of obtaining an accurate travel history.

Conversion of Total Shoulder Arthroplasty to Reverse Total Shoulder Arthroplasty: Time to Conversion and Indications at a Tertiary Care Center.

Anatomic total shoulder arthroplasty (aTSA) and reverse shoulder arthroplasty (RSA) are increasingly common, with volume projected to increase over 90% by the year 2025. Therefore, it is critical to understand the expected longevity of aTSA using modern implants and techniques, rates of conversion to RSA, and most common indications for conversion if surgeons are to properly diagnose and treat patients. A retrospective review was conducted of 800 patients who had undergone aTSA, RSA, or hemiarthroplasty (HA) between 2015 and 2019 at a tertiary-care academic medical center. All patients who had undergone primary aTSA were included. Patients who had undergone primary HA, primary RSA, or had had primary surgery at an outside hospital were excluded. Primary outcomes were indications for and time to conversion from aTSA to RSA. Secondary outcomes were indications for primary aTSA and preliminary survivorship data of modern implants. Between 2015 and 2019, 235 patients underwent primary aTSA, with a mean time to follow-up of 3.43 years (0.07-5.24 years). Mean time to conversion from aTSA to RSA was 15.6 months, with a 2.13% conversion rate (5 patients). Eighty percent of the conversions (4 patients) were due to rotator cuff tear. We found that 2.13% of primary aTSA patients at our institution were converted to RSA at a mean of 15.6 months after the primary procedure. Rotator cuff tears were the indication for 80% of these. Since conversions occurred relatively soon after primary surgery, the authors recommend use of MRI without contrast prior to surgery to possibly reduce the risk of such failures. This study was a Level 3 retrospective database review.