Which way forward? Comparing radiological outcomes using three different surgical approaches in robotic assisted total hip arthroplasty.

OBJECTIVES: To assess the accuracy and precision of acetabular component placement in robot-assisted surgery total hip arthroplasty (RAS-THA) using three different approaches. METHODS: This study is a secondary analysis from a multicenter, randomized controlled trial comparing the Trex RS Hip 1.0 robot navigation system across different surgical approaches. It involved 145 patients treated at three Chinese medical centers from June 2021 to July 2022. Patients with end-stage joint disease were randomly assigned to either the RAS or control group. Acetabular component positioning was evaluated radiographically, and registration accuracy was measured using Root Mean Square Error (RMSE). RESULTS: The overall RMSE was 0.72 mm (SD = 0.24 mm), indicating consistent accuracy regardless of surgical approach. Significant variations in anteversion were noted across groups (p = 0.001). Lateral RAS-THA showed enhanced precision. The RAS Direct Anterior Approach (DAA) group had the least deviation in the rotation center's horizontal distance (0.89 ± 1.14 mm, p = 0.0014) and minimal leg length discrepancy (2.41 ± 1.17 mm). The RAS DAA approach also produced more consistent results. CONCLUSION: Robotic assistance in THA, especially via the DAA approach, enhances the accuracy and precision of acetabular component positioning. Consistent registration accuracy across various surgical approaches confirms the reliability of these methods for THA. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov identifier is ChiCTR2100044124.

The obesity challenge in joint replacement: a multifaceted analysis of self-reported health status and exercise capacity using NHANES data: a population-based study.

BACKGROUND: Joint replacement is successful for end-stage oeteoarthritis, with obesity linked to elevated risk. But the impact of obesity on self-reported health and exercise capacity among joint replacement patients remains complex and requires investigation. METHODS: This study utilizes data from the National Health and Nutrition Examination Survey (NHANES) to examine the relationship between obesity severity, demographic factors, medical comorbidities, and self-reported health status. The relationship between general health status and BMI was analyzed using multivariable regression, and further illustrated using a restricted cubic spline. Additionally, a bibliometric analysis and systematic review was done to frame the research within the broader context of existing knowledge and demographic specifics. RESULTS: Analysis of NHANES data involving 327 joint replacement patients yielded intriguing insights. The difference in self-reported health between BMI groups did not achieve conventional statistical significance ( P =0.06), and multivariable analysis showed that even severely obese patients did not exhibit significantly elevated risk of poor/fair self-reported health compared to normal weight subjects. Among severely obese individuals (BMI>40), 40.63% still rated their health positively. However, stratified analyses indicated that obesity correlated with negative health reports across sex, age, and education strata. Notably, physical functioning emerged as a robust predictor of self-reported health, with those reporting no walking difficulties having significantly lower odds of poor/fair health (Odds ratio=0.37, P =0.01). CONCLUSION: The study highlights the need for healthcare providers to consider individual physical abilities and comorbidities alongside obesity severity when discussing treatment options with joint replacement patients. It supports tailored interventions and informed shared decision-making. Future research could explore effective weight management strategies for obese individuals undergoing joint replacement.

Parallel Spinal Pathways for Transmitting Reflexive and Affective Dimensions of Nocifensive Behaviors Evoked by Selective Activation of the Mas-Related G Protein-Coupled Receptor D-Positive and Transient Receptor Potential Vanilloid 1-Positive Subsets of Nociceptors.

The high incidence of treatment-resistant pain calls for the urgent preclinical translation of new analgesics. Understanding the behavioral readout of pain in animals is crucial for efficacy evaluation when developing novel analgesics. Mas-related G protein-coupled receptor D-positive (Mrgprd+) and transient receptor potential vanilloid 1-positive (TRPV1+) sensory neurons are two major non-overlapping subpopulations of C-fiber nociceptors. Their activation has been reported to provoke diverse nocifensive behaviors. However, what kind of behavior reliably represents subjectively conscious pain perception needs to be revisited. Here, we generated transgenic mice in which Mrgprd+ or TRPV1+ sensory neurons specifically express channelrhodopsin-2 (ChR2). Under physiological conditions, optogenetic activation of hindpaw Mrgprd+ afferents evoked reflexive behaviors (lifting, etc.), but failed to produce aversion. In contrast, TRPV1+ afferents activation evoked marked reflexive behaviors and affective responses (licking, etc.), as well as robust aversion. Under neuropathic pain conditions induced by spared nerve injury (SNI), affective behaviors and avoidance can be elicited by Mrgprd+ afferents excitation. Mechanistically, spinal cord-lateral parabrachial nucleus (lPBN) projecting neurons in superficial layers (lamina I-II o ) were activated by TRPV1+ nociceptors in naïve conditions or by Mrgprd+ nociceptors after SNI, whereas only deep spinal cord neurons were activated by Mrgprd+ nociceptors in naïve conditions. Moreover, the excitatory inputs from Mrgprd+ afferents to neurons within inner lamina II (II i ) are partially gated under normal conditions. Altogether, we conclude that optogenetic activation of the adult Mrgprd+ nociceptors drives non-pain-like reflexive behaviors via the deep spinal cord pathway under physiological conditions and drives pain-like affective behaviors via superficial spinal cord pathway under pathological conditions. The distinct spinal pathway transmitting different forms of nocifensive behaviors provides different therapeutic targets. Moreover, this study appeals to the rational evaluation of preclinical analgesic efficacy by using comprehensive and suitable behavioral assays, as well as by assessing neural activity in the two distinct pathways.