Single-Stage versus Multi-Stage Intramedullary Nailing for Multiple Synchronous Long Bone Impending and Pathologic Fractures in Metastatic Bone Disease and Multiple Myeloma

Purpose: Determine whether perioperative outcomes differ between patients who have undergone single or multi-stage IMN procedures for impending or completed pathologic fractures. Methods: Patients were classified into single-stage single-bone (SSSB), single-stage multiple-bone (SSMB), and multi-stage multiple-bone (MSMB) based on procedure timing and number of bones involved. Outcome variables compared included length of stay (LOS), in-hospital mortality and survival, initiation of rehabilitation and adjuvant therapy, and perioperative complications. Results: There were 272 IMNs placed in 181 patients (100 males, 81 females, 55.2% and 44.8%, respectively) with a mean age of 66.3 ± 12.1 years. MSMB had significantly longer LOS (24.3 ± 14.2 days) and rehabilitation initiation (3.4 ± 2.5 days) compared to SSSB (8.5 ± 7.7 and 1.8 ± 1.6 days) and SSMB (11.5 ± 7.6 and 2.0 ± 1.6 days) subjects, respectively (both; p p = 0.038). MSMB had significantly more (20%) cardiopulmonary complications than SSMB (11.1%) and SSSB (4.5%) (p = 0.027). All groups exhibited comparative survivorship (8.1 ± 8.6, 7.1 ± 7.2, and 11.4 ± 11.8 months) and in-hospital mortality (4.5%, 8.9%, and 4.0%) (all; p > 0.05). Conclusion: In comparison to MSMB, SSMB intramedullary nailing did not result in higher perioperative complication or in-hospital mortality rates in select patients with synchronous long-bone metastases but led to earlier postoperative discharge and initiation of rehabilitation

Molecular theory of solvation for supramolecules and soft matter structures: application to ligand binding, ion channels, and oligomeric polyelectrolyte gelators

We combine the statistical\u2013mechanical 1D/3D-RISM-KH molecular theory of solvation with DFT electronic structure calculations and MD and coarse-grained DPD simulations, and apply them to study association phenomena in synthetic organic soft matter and biomolecular systems. This combined approach from electronic to molecular structure and coarse-graining allows us to address complex processes occurring in solution on very long timescales, such as protein\u2013ligand binding, distributions of electrolyte solution species in ion channels, and oligomeric polyelectrolyte gelation. The statistics of rare events involving supramolecular solute and solvent is accounted for analytically within the 3D-RISM-KH molecular theory of solvation. The hybrid MD/3D-RISM-KH method for molecular dynamics of the biomolecule in the potential of mean force obtained with the molecular theory of solvation has been implemented in the Amber package. The 3D molecular theory of solvation also replaces MM/GB(PB)SA post-processing using empirical treatment of non-polar contributions with MM/3D-RISM-KH evaluation of the solvation thermodynamics. The 3D-RISM-KH theory accurately yields the solvation structure for biomolecular systems as large as the GroEL chaperonin complex, GLIC ion channel, and 3D maps of ligand binding affinity of antiprion compound to mouse PrPC prion protein at once without phenomenological approximations. We apply the DFT/1D-3D-RISM-KH/DPD multiscale approach to investigate the structural and dynamical properties and gelation ability of oligomeric polyelectrolyte gelators, towards understanding of the gelation mechanism.Peer reviewed: YesNRC publication: Ye

Increasing trend toward joint-preserving procedures for hip osteonecrosis in the United States from 2010 to 2019

Abstract Introduction The incidence of osteonecrosis of the femoral head is estimated at about 10 to 20,000 patients annually, and, when left untreated, 80% or more of cases progress to femoral head collapse. A series of joint-preserving procedures have been developed to prevent/delay the need for hip arthroplasty. The aim of this study was to provide a five-year update: (1) evaluating temporal trends of arthroplasty vs. joint-preservation techniques such as core decompression, bone grafting, osteotomies, and arthroscopy; (2) determining proportions of procedures in patients aged less than vs. over 50 years; and (3) quantifying rates of specific operative techniques. Methods A total of 10,334 patients diagnosed with osteonecrosis of the femoral head and having received hip surgery were identified from a nationwide database between 1 January 2010 and 31 December 2019, by using the International Classification of Disease, the Ninth/Tenth revision (ICD-9/10) codes. The percentage of patients managed by each operative procedure was calculated annually. To identify trends, patients were grouped by age under/over 50 years and divided into a joint-preserving and a non-joint-preserving (arthroplasty) group. Chi-squared tests were performed to compare the total number of procedures per year. Results Rates of arthroplasty far exceeded those for joint-preserving procedures. However, from 2015 to 2019, significantly more joint-preserving procedures were performed than in 2010 to 2014 (4.3% vs. 3.0%, P < 0.001). Significantly more joint-preserving procedures were performed in patients aged < 50 years relative to those ≥ 50 years (7.56% vs. 1.86%, P < 0.001). Overall, total hip arthroplasty was the most common procedure (9,814; 94.97%) relative to core decompression (331; 3.20%), hemiarthroplasty/resurfacing (102; 0.99%), bone grafting (48; 0.46%), and osteotomy (5; 0.05%). Conclusion Management of patients who have osteonecrosis of the femoral head continues to be predominantly arthroplasty procedures, specifically, total hip arthroplasty. Our findings suggest a small, but significant trend toward increased joint-preserving procedures, especially in patients under 50 years. In particular, the proportion of patients receiving core decompression has increased significantly from 2015 to 2019 relative to prior years