nuates AngⅡ-induced muscle atrophy by activation of PPARγ and suppression of miR-29b. Thumb carpometacarpal joint (TCMJ) osteoarthritis is the fourth leading cause of referral to elective hand surgery. None of the available techniques has proved superior over the others. Some techniques carry unacceptable risks for younger patients, such as loss of strength and shortening of the thumb column after total trapeziectomy, or wear and loosening after total arthroplasty. Our objective was to assess outcomes after partial arthroscopic trapeziectomy (PAT) combined with suspensionplasty using the abductor pollicis longus (APL) tendon in patients younger than 60years of age. PAT combined with suspensionplasty using the APL tendon in patients younger than 60years would restore strength in the medium-term without further surgery. We retrospectively included consecutive patients operated between 2007 and 2017, in a single centre, and aged less than 60years. All patients had isolated TCMJ osteoarthritis stage 1 to 3 according to Eaton and Glickel classification that remained symptomatic despite optimaury to the sensory branch of the radial nerve. A single patient required further surgery for persistent pain. Patients younger than 60years who are treated with this minimally invasive technique are likely to experience sustained improvements in both strength and pain intensity. Total trapeziectomy and pyrocarbon implant has also been evaluated in younger patients, who experienced pain relief and strength gains but had lower levels of satisfaction and developed complications inherent in the implants. Dibutyryl-cAMP The short time off work and low morbidity make our technique a procedure of choice in younger patients. To build on this study, a comparison of PAT and arthroplasty would be of interest. IV.IV. Peri-prosthetic hip fractures (PPHFs) are serious complications whose treatment is generally difficult due to their predominance in elderly patients with bone frailty and other comorbidities. The Vancouver classification is the most widely used and is helpful for assisting treatment decisions. However, its value for predicting morbidity and mortality has not been assessed. The objective of this retrospective study was to assess post-operative morbidity and mortality according to the fracture type in the Vancouver classification. Post-operative morbidity and mortality vary across fracture types in the Vancouver classification. A single-centre retrospective study was conducted from 1st January 2010 to 31st December 2015. All patients who had surgery for a PPHF were included. There were 88 patients, including 66 (75%) females, and mean age was 82 years. The patients were re-evaluated at least 3 years after surgery. The distribution of the fracture types was as follows Vancouver (V) A, n=7; VB, n=63 (VB1, n, and Lawton) and functional scores (MAP and HHS) decreased post-operatively in proportion to the severity of the fracture (very small losses for VA and greatest losses for VB3) (p<0.05). The short- and medium-term mortality rates in our cohort of patients with PPHFs were high and chiefly dependent on the severity of the fractures. The self-sufficiency and functional scores were better in the group with VA fractures than in the groups with VB1, VB2, VB3, and VC fractures. In any case, early weight-bearing is without doubt a key factor in limiting the impact of PPHFs on the functional outcome and on mortality. IV, retrospective study.IV, retrospective study. There is no consensus on the best salvage option after a failed trapeziometacarpal prothesis. Conserving the trapezium and inserting a pyrocarbon hemiarthroplasty implant will prevent thumb shortening and preserve the thumb's motion. The aim of this study was to evaluate the clinical and radiological outcomes in the medium term of trapeziometacarpal prothesis revisions done using the CMI pyrocarbon implant. This was a retrospective study of 28 patients with a mean age of 63.5 years. The mean time to revision was 6.1 years after the initial arthroplasty. The dominant side was operated in 70% of patients. The surgery consisted of removing the existing prosthesis, reconstructing the trapezium with a bone graft, and inserting the CMI pyrocarbon implant. The review consisted of a functional assessment (visual analog scale for pain, QuickDASH score, patient satisfaction), physical assessment (Kapandji, grip strength, key pinch strength, tip pinch strength) and radiological assessment (complications, radiolucenthe trapezium and inserting this hemiarthroplasty implant preserves the thumb's projection, length, and stability. The functional improvement experienced by patients makes this a relevant treatment option. IV; retrospective study without control group.IV; retrospective study without control group. The American College of Obstetricians and Gynecologists recommends universal screening for tobacco, alcohol, and drug use as a part of routine prenatal care. However, little is known about the prevalence of prenatal substance use screening or factors that may contribute to differential rates of screening during prenatal care. This study aimed to describe the prevalence of prenatal substance use screening by substance, year, state, and state-level prenatal substance use policies and to examine individual-level factors associated with receipt of screening. We analyzed 2016 to 2018 data from 103,608 women participating in the Pregnancy Risk Assessment Monitoring System, a population-based survey among women with recent live births. The Pregnancy Risk Assessment Monitoring System survey sampling weights were applied to all analyses. We described the percentage of individuals asked by a healthcare worker about substance use during a prenatal care appointment by substance, year, and state. Using chi-squared tof selective screening approaches on outcomes and the roles that policies, systems, and provider biases play in perpetuating these approaches is needed to advance guideline implementation efforts in prenatal care settings.Our study finds that despite recommendations for universal prenatal substance use screening, there are differences in who is actually asked about substance use during prenatal care appointments. This may be influenced by state-level prenatal substance use policies and selective screening approaches in which certain individuals are more likely to be asked about substance use during their prenatal care appointment. A better understanding of the repercussions of selective screening approaches on outcomes and the roles that policies, systems, and provider biases play in perpetuating these approaches is needed to advance guideline implementation efforts in prenatal care settings.