Total Hip Arthroplasty in Challenging Settings: Acetabular Fractures, Adolescents, Conversions, and Developmental Dysplasia of the Hip.

Background: Total hip arthroplasty (THA) is one of the most common and successful procedures for the treatment of end-stage hip arthritis. However, in certain complex scenarios, THA can present important and unique challenges, specifically following acetabular fractures in adolescent patients, following failed fixation of proximal femoral fractures, and in developmental dysplasia of the hip. As these cases involve distorted anatomy, poor bone quality, retained hardware, and previous surgeries, detailed planning, specialized instrumentation and implants, and novel surgical techniques are required.

Intravenous Injection of Tranexamic Acid in Patients with Pelvic Fractures: A Prospective Randomized Trial.

Purpose: The purpose of the study is to examine the efficacy of intravenous injections of tranexamic acid (TXA) in reducing perioperative blood loss in patients scheduled for open reduction and internal fixation for pelvic fractures (Tile B and C). A study population with greater homogeneity was selected to minimize confounding variables related to fracture and fixation methods that may reflect an accurate result.

Materials And Methods: A prospective randomized controlled trial including 100 patients who received either 15 mg/kg of TXA added to 40 mL saline twice separated by 3 hours interval or a similar volume of normal saline (~50 mL twice in same manner) intravenously.

Does minimally invasive percutaneous transilial internal fixator became an effective option for sacral fractures? A prospective study with novel implantation technique.

Aim: To assess radiological and functional outcomes of transilial internal fixator (TIFI) for treatment of sacral complete transforaminal fractures with a novel implantation technique that decrease wound irritation problems in addition to facilitating easy application of reduction methods beside showing the best entry points, screw trajectories and angles.

Methods: A Prospective case series from 2019 to 2021 was conducted at university hospital including 72 patients with Denis type 2 sacral fractures. The operative and fluoroscopy time, reduction, implantation techniques, postoperative radiological and functional data were collected and evaluated with minimum follow-up of 12 months.

Comparative Serum Analyses Identify Cytokines and Hormones Commonly Dysregulated as Well as Implicated in Promoting Osteolysis in MMP-2-Deficient Mice and Children.

Deficiency of matrix metalloproteinase 2 (MMP-2) causes a complex syndrome characterized by multicentric osteolysis, nodulosis, and arthropathy (MONA) as well as cardiac valve defects, dwarfism and hirsutism. MMP-2 deficient ( ) mice are a model for this rare multisystem pediatric syndrome but their phenotype remains incompletely characterized. Here, we extend the phenotypic characterization of MMP-2 deficiency by comparing the levels of cytokines and chemokines, soluble cytokine receptors, angiogenesis factors, bone development factors, apolipoproteins and hormones in mice and humans.

Role of arthroscopy for the diagnosis and management of post-traumatic hip pain: a prospective study.

The current published literature regarding the role of hip arthroscopy in the diagnosis and management of post-traumatic hip pain is still limited. Therefore, we conducted the present prospective study to determine the value of hip arthroscopy in the diagnosis and management of various causes of hip pain after traumatic conditions. The present study included a prospective cohort of 17 patients with symptomatic post-traumatic hip pain.

A Cell-Free Content Mixing Assay for SNARE-Mediated Multivesicular Body-Vacuole Membrane Fusion.

Endocytosis is a fundamental process underlying diverse eukaryotic physiology. The terminal stage of this process is membrane fusion between the perimeter membrane of a late endosome filled with intraluminal vesicles, or multivesicular body (MVB), and the lysosome membrane to facilitate catabolism of internalized biomaterials or surface polytopic proteins. To comprehensively understand the mechanisms underlying MVB-lysosome membrane fusion, we developed a quantitative, cell-free assay to study this SNARE-mediated event in molecular detail using Saccharomyces cerevisiae and its vacuolar lysosome, or vacuole, as models.

Rab-Effector-Kinase Interplay Modulates Intralumenal Fragment Formation during Vacuole Fusion.

Upon vacuolar lysosome (or vacuole) fusion in S. cerevisiae, a portion of membrane is internalized and catabolized. Formation of this intralumenal fragment (ILF) is important for organelle protein and lipid homeostasis and remodeling.

The Na(K)/H exchanger Nhx1 controls multivesicular body-vacuolar lysosome fusion.

Loss-of-function mutations in human endosomal Na(K)/H exchangers (NHEs) NHE6 and NHE9 are implicated in neurological disorders including Christianson syndrome, autism, and attention deficit and hyperactivity disorder. These mutations disrupt retention of surface receptors within neurons and glial cells by affecting their delivery to lysosomes for degradation. However, the molecular basis of how these endosomal NHEs control endocytic trafficking is unclear.

Distinct features of multivesicular body-lysosome fusion revealed by a new cell-free content-mixing assay.

When marked for degradation, surface receptor and transporter proteins are internalized and delivered to endosomes where they are packaged into intralumenal vesicles (ILVs). Many rounds of ILV formation create multivesicular bodies (MVBs) that fuse with lysosomes exposing ILVs to hydrolases for catabolism. Despite being critical for protein degradation, the molecular underpinnings of MVB-lysosome fusion remain unclear, although machinery underlying other lysosome fusion events is implicated.

Fixation of quadrilateral plate fractures of the acetabulum using the buttress screw: A novel technique.

Introduction: Quadrilateral plate fractures constitute one of the most challenging components of acetabular fractures. The objective of this study is to describe and evaluate the novel technique of buttress screw fixation of the quadrilateral plate component of the acetabular fractures.

Patients & Methods: Forty cases of acetabular fracture with associated quadrilateral plate component were included in the study.

Selective Lysosomal Transporter Degradation by Organelle Membrane Fusion.

Lysosomes rely on their resident transporter proteins to return products of catabolism to the cell for reuse and for cellular signaling, metal storage, and maintaining the lumenal environment. Despite their importance, little is known about the lifetime of these transporters or how they are regulated. Using Saccharomyces cerevisiae as a model, we discovered a new pathway intrinsic to homotypic lysosome membrane fusion that is responsible for their degradation.

How and why intralumenal membrane fragments form during vacuolar lysosome fusion.

Lysosomal membrane fusion mediates the last step of the autophagy and endocytosis pathways and supports organelle remodeling and biogenesis. Because fusogenic proteins and lipids concentrate in a ring at the vertex between apposing organelle membranes, the encircled area of membrane can be severed and internalized within the lumen as a fragment upon lipid bilayer fusion. How or why this intralumenal fragment forms during fusion, however, is not entirely clear.

Anterior cruciate ligament reconstruction; is a tourniquet necessary? A randomized controlled trial.

Purpose: This work aimed at studying the effect of tourniquet use on surgical performance and peri-operative outcomes of anatomic single-bundle ACL reconstruction.

Methods: Eighty-four patients undergoing ACL surgery were randomized into two groups: the tourniquet (A) group and the non-tourniquet (B) group. Post-operative pain, need for analgesics, the volume of blood obtained in the drain, girth diameter changes in the thigh and calf, muscle strength and amount of haemarthrosis were used as outcome measures to compare the two groups.