Establishing minimal clinically important differences and patient acceptable symptom state thresholds following birmingham hip resurfacing.

INTRODUCTION: Birmingham Hip Resurfacing (BHR) has emerged as a compelling and innovative alternative to total hip arthroplasty (THA), especially among young, active patients. However, the Minimal Clinically Important Difference (MCID) and the Patient Acceptable Symptom State (PASS) thresholds have not yet been determined for patients undergoing BHR. Therefore, the current study aimed to (1) determine the MCID and PASS thresholds for both the Hip disability and Osteoarthritis Outcome Score (HOOS)-Pain and HOOS physical function shortform (PS), for patients who underwent BHR; and (2) identify factors influencing the achievement of MCID and PASS for HOOS-Pain and HOOS-PS. METHODS: Prospectively collected data from patients undergoing BHR was analyzed. Patients with osteoarthritis and completed preoperative and 1-year postoperative PROMs were included. Distribution-based and anchored-based approaches were used to estimate MCID and PASS, respectively. The optimal cut-off point for PASS thresholds was calculated using the Youden index. RESULTS: MCID for HOOS-Pain and PS were calculated to be 9.2 and 9.3, respectively. The PASS threshold for HOOS-Pain and PS were ≥ 77.7 and ≥ 87.3, respectively. The current study identified several factors affecting postoperative achievement of thresholds. Baseline Mental Component Summary (MCS) scores were a predictor for achieving MCID for postoperative HOOS-Pain, achieving MCID for postoperative HOOS-PS, achieving PASS for postoperative HOOS-Pain, and achieving PASS for postoperative HOOS-PS. Furthermore, baseline HOOS-Pain was a significant predictor for achieving MCID for postoperative HOOS-PS, achieving PASS for postoperative HOOS-Pain, and achieving PASS for postoperative HOOS-PS. CONCLUSIONS: MCID and PASS thresholds were established for HOOS-Pain and PS domains following BHR with most patients achieving these clinically meaningful benchmarks. Additionally, several factors affecting achievement of MCID and PASS were identified, including modifiable risk factors that may allow clinicians to implement optimization strategies and further improve outcomes.

The complement system as a target in cancer immunotherapy.

Malignant cells are part of a complex network within the tumor microenvironment, where their interaction with host cells and soluble mediators, including complement components, is pivotal. The complement system, known for its role in immune defense and homeostasis, exhibits a dual effect on cancer progression. This dichotomy arises from its antitumoral opsonophagocytosis and cytotoxicity versus its protumoral chronic inflammation mediated by the C5a/C5aR1 axis, influencing antitumor T-cell responses. Recent studies have revealed distinct co-expression patterns of complement genes in various cancer types, correlating with prognosis. Notably, some cancers exhibit co-regulated overexpression of complement genes associated with poor prognosis, while others show favorable outcomes. However, significant intra-patient heterogeneity further complicates this classification. Moreover, the involvement of locally produced and intracellular complement proteins adds complexity to the tumor microenvironment dynamics. This review highlights the unique interplay of complement components within different cancers and patient cohorts, showing that "one size does not fit all", for complement in cancer. It summarizes the clinical trials for complement targeting in cancer, emphasizing the need for tailored therapeutic approaches. By elucidating the mechanistic basis of complement's context-dependent role, this review aims to facilitate the development of personalized cancer therapies, ultimately improving patient care and outcomes.

Surgical Management of Chronic Morel-Lavallée Lesion with Minimal Cosmetic Scarring: A Case Report.

Introduction: Morel-Lavallée lesion (MLL) is a closed degloving injury that occurs after traumatic damage to soft tissue, leading to the formation of an encapsulated serosanguinous collection of fluid. Although some MLLs resolve spontaneously, chronic MLLs present with a significant risk of infection and may impede patients' quality of life. Chronic lesions require surgical intervention to evacuate and debride the hematoma, often resulting in severe cosmetic damage postoperatively. Case Report: We documented a large 19.4 cm × 4.2 cm × 15.10 cm MLL on the right lateral hip that presented a significant impediment to the patient's daily functions. After the failure of conservative management, the patient was treated surgically through a minimal incision debridement procedure, utilizing a wound drain and vacuum-assisted compressional dressing upon closure. Excellent 1-year post-operative outcomes were achieved with no recurrence of the lesion and limited cosmetic evidence of the MLL. Conclusion: This case highlights the value of a limited incisional debridement procedure for the management of a chronic Morel-Lavellée lesion. When using this technique, surgeons can effectively treat these lesions with promising short-term outcomes and minimal wound scarring.

Identifying Critical Evidence Gaps in Wound Closure and Incision Management After Total Knee Arthroplasty: Delphi Panel Insights.

INTRODUCTION: In orthopaedic surgery, particularly total knee arthroplasty (TKA), the management of surgical wounds is critical for optimal wound healing and successful patient outcomes. Despite advances in surgical techniques, challenges persist in effectively managing surgical wounds to prevent complications and infections. This study aimed to identify and address the critical evidence gaps in wound management in TKA, including preoperative optimization, intraoperative options, and for the avoidance of postoperative complications. These are important issues surrounding wound management, which is essential for improving patient recovery and the overall success of the surgery. METHODS: Utilizing the Delphi method, this study brought together 20 experienced orthopaedic surgeons from Europe and North America. Conducted from April to September 2023, the process involved three stages: an initial electronic survey, a virtual meeting, and a concluding electronic survey. The panel reviewed and reached a consensus on 26 specific statements about wound management in TKA based on a comprehensive literature review. During these three stages and after further panel review, an alternative goal of the Delphi panel was to also identify critical evidence gaps in the current understanding of wound management practices for TKA. RESULTS: While the panel reached consensus on various wound management practices, they highlighted several major evidence gaps. Also, there was general consensus on issues such as wound closure methods including the use of mesh-adhesive dressings, skin glue, staples, sutures (including barbed sutures),and negative-pressure wound therapy (NPWT). However, it was deemed necessary that further evidence needs to be generated to address the cost-effectiveness of each and develop best practices for promoting patient outcomes. The identification of these gaps points to areas requiring more in-depth research and improvements to enhance wound care in TKA. DISCUSSION: The identification of these major evidence gaps underscores the need for targeted research in wound management surrounding TKA. Addressing these evidence gaps is crucial for the future development of more effective, efficient, and patient-friendly wound care strategies. Future research should prioritize these areas, focusing on comparative effectiveness studies and further developing clear guidelines for the use of emerging technologies. Bridging these gaps has the potential to improve patient outcomes, reduce complications, and elevate the overall success rate of TKA surgeries.

Retrieval Analysis of Titanium Nitride Coatings for Orthopaedic Implants.

BACKGROUND: The first generation of titanium nitride (TiN) coatings for orthopaedic implants was clinically introduced in the 1990s because of their promising biocompatibility, wear resistance, and corrosion resistance. This study evaluated the in vivo performance of early TiN-coated knee and hip implants, focusing on the bearing surfaces and mechanisms of in vivo damage. METHODS: There were 13 TiN-coated implants (5 knee and 8 hip) retrieved from 8 patients as part of a multi-institutional implant retrieval program. The average implantation time was 4.25 years for knees and 17.5 years for hips. Implant revisions occurred for various reasons, including polyethylene wear, loosening, pain, infection, and instability. Components were examined using a semiquantitative scoring method, and surface roughness measurements were performed using white-light interferometry. Surface morphology, chemistry, and particle characterization were also assessed by scanning electron microscopy. RESULTS: For hips, mild corrosion was found on femoral head tapers, along with severe scratching on certain femoral heads. Knee implants exhibited low burnishing and scratching for both mechanisms. Roughness measurements (Sa) were 37.3 nm (interquartile range = 22.0 to 62.4) for hips and 85.3 nm (interquartile range = 66.3 to 110) for knees. The observed scratch depth in both hip and knee implants due to third-body particles ranged from 0.3 to 1.3 µm. The coating coverage remained intact in the majority of the implants, with 2 cases of small, localized cohesive chipping and substrate exposure. CONCLUSIONS: The results of this study confirm the potential in vivo durability of early TiN coatings and will be useful in benchmarking wear tests for modern TiN-coated orthopaedic implants.

Anti-HMGCR (Hydroxy-3-Methylglutaryl-CoA Reductase) Myopathy: A Rare Cause of Proximal Muscle Weakness.

Idiopathic inflammatory myopathy (IIM) represents a rare group of autoimmune conditions resulting in muscle weakness and includes polymyositis, dermatomyositis, immune-mediated necrotizing myopathy (IMNM), overlap myositis, and inclusion body myositis. Anti-3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR) antibody IMNM represents a rare but increasingly recognized subtype of IIM. Here we report a case of a 65-year-old woman on rosuvastatin who presented with two months of progressive proximal muscle weakness, significant truncal weakness, and elevated creatine kinase concerning for rhabdomyolysis and inflammatory myopathy. The patient was eventually diagnosed on day 8 of her hospital stay with anti-HMGCR antibody IMNM after delayed testing for this specific myopathy. Increased awareness of this IIM subtype, as well as its risk factors and presenting features, might improve rapidity of testing and shorten hospital stays if the diagnosis is considered in the emergency department or early in the hospital course.

Oxidation and Damage Mechanisms of Second-Generation Highly Cross-Linked Polyethylene Tibial Inserts.

BACKGROUND: After clinical introduction in 2005, sequentially annealed, highly cross-linked polyethylene (SA HXLPE) was studied for retrievals with short implantation times; however, long-term follow-ups are lacking. The objective of this study was to examine and compare the revision reasons, damage mechanisms, and oxidation indices of SA HXLPE and conventional gamma inert-sterilized (Gamma Inert) ultra-high-molecular-weight polyethylene tibial inserts implanted for >5 years. METHODS: There were 74 total knee arthroplasty tibial inserts (46 SA HXLPEs, 28 Gamma Inerts) implanted for >5 years (mean 7 ± 2 years) retrieved as part of a multicenter retrieval program. Cruciate-retaining implants comprised 44% of the SA HXLPEs and 14% of the Gamma Inerts. Patient factors and revision reasons were collected from revision operating notes. A semiquantitative scoring method was used to assess surface damage mechanisms. Oxidation was measured using Fourier transform infrared microscopy according to American Society for Testing and Materials 2102. Differences between cohorts were assessed with Mann-Whitney U-tests. RESULTS: Loosening (Gamma Inert: 17 of 28, SA HXLPE: 15 of 46) and instability (Gamma Inert: 6 of 28, SA HXLPE: 15 of 46) were the most common revision reasons for both cohorts. The most prevalent surface damage mechanisms were burnishing, pitting, and scratching, with burnishing of the condyles being higher in Gamma Inert components (P = .022). Mean oxidation was higher in the SA HXLPE inserts at the articulating surface (P = .002) and anterior-posterior faces (P = .023). No difference was observed at the backside surface (P = .060). CONCLUSIONS: Revision reasons and surface damage mechanisms were comparable in the Gamma Inert and SA cohorts. Further studies are needed to continue to assess the in vivo damage and clinical relevance, if any, of oxidation in SA HXLPE over longer implantation times, particularly for implants implanted for more than 10 years.

Conversion Birmingham Hip Resurfacing in Managing Post-traumatic Arthritis With Retained Femoral Hardware: A Case Report.

CASE: A 70-year-old man with a year-long history of arthritic pain in his left hip presented to our clinic. He had a left intertrochanteric hip fracture 6 years ago, fixed with an open reduction internal fixation with a cephalomedullary nail. He underwent a conversion Birmingham Hip Resurfacing (BHR) with removal of the proximal helicoidal blade and retention of the intramedullary nail. At 7-year follow-up, the patient reported satisfactory clinical outcomes and excellent radiographic fixation. CONCLUSION: This case highlights using conversion BHR in patients with post-traumatic arthritis with retained femoral hardware as an alternative to conventional total hip arthroplasty.

Probing Glycerolipid Metabolism using a Caged Clickable Glycerol-3-Phosphate Probe.

In this study, we present the probe SATE-G3P-N3 as a novel tool for metabolic labeling of glycerolipids (GLs) to investigate lipid metabolism in yeast cells. By introducing a clickable azide handle onto the glycerol backbone, this probe enables general labeling of glycerolipids. Additionally, this probe contains a caged phosphate moiety at the glycerol sn-3 position to not only facilitate probe uptake by masking negative charge but also to bypass the phosphorylation step crucial for initiating phospholipid synthesis, thereby enhancing phospholipid labeling. The metabolic labeling activity of the probe was thoroughly assessed through cellular fluorescence microscopy, mass spectrometry (MS), and thin-layer chromatography (TLC) experiments. Fluorescence microscopy analysis demonstrated successful incorporation of the probe into yeast cells, with labeling predominantly localized at the plasma membrane. LCMS analysis confirmed metabolic labeling of various phospholipid species (PC, PS, PA, PI, and PG) and neutral lipids (MAG, DAG, and TAG), and GL labeling was corroborated by TLC. These results showcased the potential of the SATE-G3P-N3 probe in studying GL metabolism, offering a versatile and valuable approach to explore the intricate dynamics of lipids in yeast cells.

Predictive Modeling of Medical- and Orthopaedic-Related 90-Day Readmissions Following Primary Total Hip Arthroplasty.

BACKGROUND: The rate of unplanned hospital readmissions following total hip arthroplasty (THA) varies from 3 to 10%, representing a major economic burden. However, it is unknown if specific factors are associated with different types of complications (ie, medical or orthopaedic-related) that lead to readmissions. Therefore, this study aimed to: (1) determine the overall, medical-related, and orthopaedic-related 90-day readmission rate; and (2) develop a predictive model for risk factors affecting overall, medical-related, and orthopaedic-related 90-day readmissions following THA. METHODS: A prospective cohort of primary unilateral THAs performed at a large tertiary academic center in the United States from 2016 to 2020 was included (n = 8,893 patients) using a validated institutional data collection system. Orthopaedic-related readmissions were specific complications affecting the prosthesis, joint, and surgical wound. Medical readmissions were due to any other cause requiring medical management. Multivariable logistic regression models were used to investigate associations between prespecified risk factors and 90-day readmissions, as well as medical and orthopaedic-related readmissions independently. RESULTS: Overall, the rate of 90-day readmissions was 5.6%. Medical readmissions (4.2%) were found to be more prevalent than orthopaedic-related readmissions (1.4%). The area under the curve for the 90-day readmission model was 0.71 (95% confidence interval: 0.69 to 0.74). Factors significantly associated with medical-related readmissions were advanced age, Black race, education, Charlson Comorbidity Index, surgical approach, opioid overdose risk score, and nonhome discharge. In contrast, risk factors linked to orthopaedic-related readmissions encompassed body mass index, patient-reported outcome measure phenotype, nonosteoarthritis indication, opioid overdose risk, and nonhome discharge. CONCLUSIONS: Of the overall 90-day readmissions following primary THA, 75% were due to medical-related complications. Our successful predictive model for complication-specific 90-day readmissions highlights how different risk factors may disproportionately influence medical versus orthopaedic-related readmissions, suggesting that patient-specific, tailored preventive measures could reduce postoperative readmissions in the current value-based health care setting.

Recognizing the Sex Disparity in Surgeons Performing Total Knee Arthroplasty.

BACKGROUND: There is an unambiguous sex disparity in the field of orthopaedic surgery, with women making up only 7.4% of practicing orthopaedic surgeons in 2022. This study seeks to evaluate the sex distribution among orthopaedic surgeons engaged in primary total knee arthroplasty (TKA) between 2013 and 2020, as well as the procedural volume attributed to each provider. METHODS: We retrospectively queried the Medicare dataset to quantify all physicians reporting orthopaedic surgery as their specialty and performing primary TKA from 2013 to 2020. Healthcare Common Procedure Coding System codes for primary TKA procedures were used to extract associated utilization and billing provider information. Trend analyses were performed with 2-sided correlated Mann-Kendall tests to evaluate trends in the number of surgeons by sex and the women-to-men surgeon ratio. RESULTS: During the study period, 6,198 to 7,189 surgeons billed for primary TKA. Of this number, an average of 2% were women. The mean number of procedures billed for by men was 39.02/y (standard deviation: 34.54), and by women was 28.76/y (standard deviation: 20.62) (P < .001). There was no significant trend in the number of men or women surgeons who billed for primary TKA during the study period. Trend analysis of the women-to-men ratio demonstrated an increasing trend of statistical significance (P = .0187). CONCLUSIONS: There was a significant upward trend in the women-to-men ratio of surgeons who billed for primary TKA. However, there remains a colossal gender gap, as women only made up 2.4% of surgeons who billed for the procedure. The current study raises awareness of the notable discrepancy in the average number of TKAs performed by women as compared to men. The orthopaedic community should aim to determine ways to increase the number of women arthroplasty surgeons along with the opportunities that women have to perform TKAs.

How-To Create an Orthopaedic Systematic Review: A Step-by-step Guide Part II: Study Execution.

Systematic reviews are the apex of the evidence-based pyramid, representing the strongest form of evidence synthesizing results from multiple primary studies. In particular, a quantitative systematic review, or meta-analysis, pools results from multiple studies to help answer a respective research question. The aim of this review is to serve as a guide on how to: (1) design, (2) execute, and (3) publish an orthopaedic arthroplasty systematic review. In Part II, we focus on methods to assess data quality through the Cochrane Risk of Bias, Methodological Index for Nonrandomized Studies criteria, or Newcastle-Ottawa scale; enumerate various methods for appropriate data interpretation and analysis; and summarize how to convert respective findings to a publishable manuscript (providing a previously published example). Use of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines is recommended and standard in all scientific literature, including that of orthopedic surgery. Pooled analyses with forest plots and associated odds ratios and 95% confidence intervals are common ways to present data. When converting to a manuscript, it is important to consider and discuss the inherent limitations of systematic reviews, including their inclusion and/or exclusion criteria and overall quality, which can be limited based on the quality of individual studies (eg, publication bias, heterogeneity, search/selection bias). We hope our papers will serve as starting points for those interested in performing an orthopaedic arthroplasty systematic review.

Trends in Gender Diversity Among Total Hip Arthroplasty Surgeons.

INTRODUCTION: A pronounced gender imbalance is evident among orthopaedic surgeons. In the field of arthroplasty, there exists a dearth of comprehensive data regarding gender representation. This study aimed to analyze the gender diversity, or lack thereof, within the field of total hip arthroplasty (THA). In addition, this study used literature review to identify possible reasons for the gender disparity among THA surgeons and identify the best next steps to promote gender equity within orthopaedics. METHODS: A retrospective analysis was conducted using the Medicare Provider Utilization and Payment Data: Physician and Other Practitioners data set to quantify orthopaedic surgeons who performed primary THA procedures from 2013 to 2020. To assess trends in the number of hip surgeons by sex and the evolving female-to-male ratio, two-sided correlated Mann-Kendall tests were conducted. RESULTS: Overall, 3,853 to 4,550 surgeons billed for primary THA annually. Of this number, an average of 1.7% was female. The mean number of services billed for by male surgeons was 31.62 ± 24.78 per year and by female surgeons was 26.43 ± 19.49 per year. Trend analysis of female-to-male ratio demonstrated an increasing trend of statistical significance (P = 0.009). The average number of procedures by female surgeons annually remained stable throughout the study, whereas there was a steady increase in that for male surgeons. CONCLUSION: Results showed a notable and sustained upward trajectory from 2013 to 2020 in the number of female surgeons billing for THA along with the female-to-male ratio. However, female surgeons constitute a mere 2% of surgeons engaging in primary THA billing. Furthermore, the annual average number of THAs conducted by female surgeons exhibited constancy, whereas there was a gradual increase in the median number of annual procedures performed by their male counterparts. Future studies should aim to identify and resolve specific barriers prohibiting female medical students from pursuing and obtaining a career as an orthopaedic THA surgeon. STUDY DESCRIPTION: Retrospective analysis using the Medicare Provider Utilization and Payment Data: Physician and Other Practitioners data set.

Genome-wide CRISPR screens identify novel regulators of wild-type and mutant p53 stability.

Tumor suppressor p53 (TP53) is frequently mutated in cancer, often resulting not only in loss of its tumor-suppressive function but also acquisition of dominant-negative and even oncogenic gain-of-function traits. While wild-type p53 levels are tightly regulated, mutants are typically stabilized in tumors, which is crucial for their oncogenic properties. Here, we systematically profiled the factors that regulate protein stability of wild-type and mutant p53 using marker-based genome-wide CRISPR screens. Most regulators of wild-type p53 also regulate p53 mutants, except for p53 R337H regulators, which are largely private to this mutant. Mechanistically, FBXO42 emerged as a positive regulator for a subset of p53 mutants, working with CCDC6 to control USP28-mediated mutant p53 stabilization. Additionally, C16orf72/HAPSTR1 negatively regulates both wild-type p53 and all tested mutants. C16orf72/HAPSTR1 is commonly amplified in breast cancer, and its overexpression reduces p53 levels in mouse mammary epithelium leading to accelerated breast cancer. This study offers a network perspective on p53 stability regulation, potentially guiding strategies to reinforce wild-type p53 or target mutant p53 in cancer.

Short-term Comparison of Survivorship and Functional Outcomes for Metaphyseal Cones with Short and Long Stems in Revision Total Knee Arthroplasty.

Printed porous titanium metaphyseal cones have become a mainstay for managing bone loss in revision total knee arthroplasty (rTKA). A short or long stem is routinely used when implanting a cone to augment fixation and offload stresses. This retrospective analysis compared the short-term survivorships and functional outcomes for use of a short or long stem with a metaphyseal cone.A total of 179 cases using metaphyseal cones and stems with median follow-up of 1.95 years (interquartile range, 1.00-2.14) were compared based on stem type. There were 55 cases with long stem(s) and 124 cases with short stem(s). Cases with both long and short stems were excluded. Demographics, Kaplan-Meier survivorships, and preoperative and 1-year postoperative patient-reported outcome measures (PROMs; 2011 Knee Society Score [KSS] objective knee score, function, and satisfaction scores; EuroQol five-dimension scale; and Short Form Survey Physical Component Summary and Mental Component Summary scores) were compared using t-tests with a significance level of α = 0.05. There were no significant differences in body mass index (mean ± standard deviation) or sex (men [%]) between the short and long stem cohorts (32.3 ± 5.3, 36.3% and 31.5 ± 5.5, 38.2%, respectively; p > 0.05). Patients who had short stems were younger (65.9 ± 8.8 vs. 69.0 ± 9.4, p = 0.0323).Revision-free survivorship for the femoral or tibial component was 100% for long stems and 98.2% for short stems at 1 and 2 years, respectively (log-rank p = 0.6330). The two revisions in the short group were for infection, thus the survivorship for aseptic loosening was 100% at 2 years for both cohorts. There were no significant differences in preoperative or postoperative PROMs.This study demonstrated that highly porous printed metaphyseal cones provided rTKA with excellent early survivorship and similar PROMs whether a short or long stem was used. Additional studies will be needed to discern longer term differences.

Safety Profile of Seven-Day Intra-articular Antibiotic Irrigation for the Treatment of Chronic Periprosthetic Joint Infection: A Prospective Randomized Phase II Comparative Study.

BACKGROUND: Systemic intravenous antimicrobials yield poor outcomes during treatment of periprosthetic joint infection due to the inability to obtain minimum biofilm eradication concentrations. This study evaluated the safety of a novel method of optimized local delivery of intra-articular antibiotics (IAAs). METHODS: This was a Phase II, multicenter, prospective randomized trial evaluating safety of a rapid (seven-day) two-stage exchange arthroplasty with IAA irrigation compared to standard two-stage exchange. The Experimental Group received irrigation using 80 mg tobramycin daily with a 2-hour soak, followed by hourly irrigation using 125 mg vancomycin with a 30-minute soak via an intramedullary irrigation device. The Control Group received an antibiotic-loaded cement spacer with vancomycin (average 8.4 g) and tobramycin (average 7.1 g, total 16 g antibiotics). Both groups received 12 weeks of systemic antibiotics following Stage 2. Safety measures included adverse events, peak vancomycin/tobramycin serum concentrations (Experimental Group), blood transfusion, and mortality. There were thirty-seven patients randomized to the Experimental Group and 39 to control. There was no difference in baseline demographics or comorbidities. RESULTS: There were no antibiotic medication-related adverse events and 2 serious adverse events related to antibiotic instillation. Of 188 vancomycin peak measurements, 69% had detectable serum level concentrations, with all concentrations well below the maximum acceptable trough threshold of 20 µg/mL. Of the 103 tobramycin peak measurements, 45% had detectable levels, with all below the maximum acceptable peak threshold of 18 to 24 µg/mL. There was no difference in blood transfused per subject (Experimental: 655 mL versus Control: 792 mL; P = .4188). There were two (2) deaths in the Experimental Group and four (4) in the control. CONCLUSIONS: The use of IAA is safe with minimal systemic antibiotic exposure. There was no difference in the rates or severity of serious adverse events between groups. Further research is being conducted to examine treatment efficacy.

[McArdle's disease revealed by acute low back pain]. / Une maladie de McArdle révélée par une lombalgie aiguë.

INTRODUCTION: McArdle disease, or glycogen storage disease type V (GSD 5), is a rare metabolic myopathy linked to an autosomal recessive myophosphorylase deficiency. CASE REPORT: We report the case of a 17-year-old male patient who was referred to the emergency department for the management of acute inflammatory low back pain, without traumatic context, associated with an increase of CK at 66,336 UI/L (N<192UI/L) and a CRP at 202mg/L. The immunological assessment was negative and the spinal MRI showed images in favor of necrotizing fasciitis affecting the erector spinae muscles, among others. Faced with the description of difficulties in practicing physical activities since childhood and a non-ischaemic forearm exercise test showing no elevation in lactacidemia, genetic tests were carried out, finding two heterozygous variants in the PYGM gene: c.1963G>A (p.Glu655Lys) class 5 and c.2178-1G>A class 4, confirming the diagnosis of McArdle disease. DISCUSSION: GSD 5 is a disease characterized essentially by muscular fatigability during exercise. The case reported here is original in the clinical circumstances leading to the diagnosis, i.e., inaugural acute low back pain with rhabdomyolysis. This symptomatology had already been described before, but in a patient whose diagnosis was already known. Spinal MRI showed non-specific muscle inflammation and necrosis. Muscle biopsy only found necrosis but no pathological elements typical of the diagnosis. If the symptoms are suggestive, it may be preferable to directly perform a non-ischaemic forearm exercise test, in order to go directly to molecular genetic analysis. There is no specific curative treatment of GSD 5. However, some measures can be implemented to limit the symptoms, such as learning physical exercises, limiting intense efforts and adopting dietary recommendations.

"I felt so powerful to have this love in me": A grounded theory analysis of the experiences of people living with and recovering from eating disorders while in diverse romantic relationships.

Romantic partners have the potential to influence attitudes and behaviors related to body image and disordered eating. However, the role that romantic relationships can play in eating disorder (ED) recovery has not been comprehensively investigated. The present study aimed to explore the ways that people living with and recovering from EDs experience their romantic relationships, with the specific objective of developing a novel theoretical framework, grounded in the experiences of people in diverse romantic relationships, to guide future research on the topic. Semi-structured individual interviews were conducted with 66 people (45 cisgender women, 11 cisgender men, 9 nonbinary people, and 1 transgender man) living with and recovering from EDs while in romantic relationships. Our grounded theory analysis yielded a theoretical model of ED management in romantic relationships, revealing that Individual and Relationship Characteristics intersected with Relationship-Related Stressors and were navigated using Eating Disorder and Relationship Management Strategies. Combined with Partner Support and Tensions, these management strategies were related to Relationship and Mental Health Outcomes, which affected and were affected by Future Concerns. Future researchers should continue to build on, expand, and modify this model and further explore the role of romantic relationships in the experience of people living with EDs.

Stepping Up Recovery: Integrating Patient-reported Outcome Measures and Wearable Technology for Rehabilitation Following Knee Arthroplasty.

Improvement after knee arthroplasty (KA) is often measured using patient-reported outcome measures (PROMs). However, PROMs are limited due to their subjectivity. Therefore, wearable technology is becoming commonly utilized to objectively assess physical activity and function. We assessed the correlation between PROMs and step/stair flight counts in total (TKA) and partial knee arthroplasty (PKA) patients.Analysis of a multicenter, prospective, longitudinal cohort study investigating the collection of average daily step and stair flight counts, was performed. Subjects (N = 1,844 TKA patients and N = 489 PKA patients) completed the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) and provided numerical rating scale pain scores pre- and postoperatively. Only patients who reported living in a multilevel home environment (N = 896 TKA patients and N = 258 PKA patients) were included in analysis of stair flight counts. Pearson correlation coefficients were calculated to determine correlations between variables.Among TKA patients, pain scores demonstrated a negative correlation to mean step counts at preoperative (r = -0.14, p < 0.0001) and 1-month follow-up (r = -0.14, p < 0.0001). Similar negative correlations were true for pain and stair flight counts at preoperative (r = -0.16, p < 0.0001) and 1-month follow-up (r = -0.11, p = 0.006). KOOS JR scores demonstrated weak positive correlations with mean step counts at preoperative (r = 0.19, p < 0.0001) and 1-month postoperative (r = 0.17, p < 0.0001). Similar positive correlations were true for KOOS JR scores and stair flight counts preoperatively (r = 0.13, p = 0.0002) and at 1-month postoperatively (r = 0.10, p = 0.0048). For PKA patients, correlations between pain and KOOS JR with step/stair counts demonstrated similar directionality.Given the correlation between wearable-generated data and PROMs, wearable technology may be beneficial in evaluating patient outcomes following KA. By combining subjective feedback with the objective data, health care providers can gain a holistic view of patients' progress and tailor treatment plans accordingly.

24-Year-Old Patient with Klippel-Trenaunay Syndrome Underwent Cementless Robotic Cruciate-Retaining TKA: A Case Report.

CASE: A 24-year-old man with Klippel-Trenaunay syndrome (KTS) presented with severe knee osteoarthritis unresponsive to conservative measures. Owing to end-stage, debilitating arthritic symptoms, surgery was pursued. Careful preoperative, multidisciplinary planning/treatment included magnetic resonance imaging to characterize the venous malformations throughout the right lower extremity, preoperative sclerotherapy, sirolimus, and robotic-assisted cementless total knee arthroplasty (TKA). CONCLUSION: Cementless robotic-assisted TKA with selective patellar resurfacing can be a viable option for young KTS patients with severe osteoarthritis when a meticulous multidisciplinary approach, including sclerotherapy and advanced imaging, is undertaken to analyze vascular abnormalities, minimize surgical risks, preserve bone stock, and optimize outcomes.