dGEMRIC and CECT Comparison of Cationic and Anionic Contrast Agents in Cadaveric Human Metacarpal Cartilage.

Magnetic resonance imaging (MRI) and computed tomography (CT) are widely used to image cartilage and their diagnostic capability is enhanced in the presence of contrast agents. The aim of the study is to directly compare the performance between commercial anionic MRI (Gd(DTPA), Gd2-) and CT (Ioxaglate, Iox1-) contrast agents with novel cationic MRI (Gd(DTPA)Lys2 , Gd4+) and CT (CA4+) contrast agents for assessment of cartilage mechanical and biochemical properties using the ex vivo human osteoarthritis metacarpal cartilage model. First, indentation testing was conducted to obtain the compressive modulus of the human fifth metacarpals. The samples were then immersed in the anionic and cationic contrast agents prior to delayed gadolinium-enhanced MRI of cartilage and CT scanning, respectively. The cartilage glycosaminoglycan (GAG) content and distribution were determined using the 1,9-dimethylmethylene blue assay and Safranin-O histology. Cationic agents significantly accumulate in cartilage compared with anionic agents. Significant positive correlations (p < 0.05) exist between imaging results of cationic agents and GAG content (Gd4+: R2 = 0.43; CA4+: R2 = 0.67) and indentation equilibrium modulus (Gd4+: R2 = 0.48; CA4+: R2 = 0.77). Significant negative correlations are observed between anionic MRI relaxation times, but not contrast-enhanced computed tomography attenuation and cartilage GAG content (Gd2-: R2 = 0.56, p < 0.05; Iox1-: R2 = 0.31, p > 0.05) and indentation equilibrium modulus (Gd2-: R2 = 0.38, p < 0.05; Iox1-: R2 = 0.17, p > 0.05). MRI or CT with cationic contrast agents provides greater sensitivity than their anionic analogs at assessing the biochemical and biomechanical properties of ex vivo human metacarpal cartilage. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:719-725, 2020.

The Relationship between Preoperative Expectations and the Short-Term Postoperative Satisfaction and Functional Outcome in Lumbar Spine Surgery: A Systematic Review.

Study Design Systematic review. Objective To examine the relationship between the patient's preoperative expectations and short-term postoperative satisfaction and functional outcome in lumbar spine surgery. Methods The Medline, Embase, and Cochrane databases were queried using a predefined search algorithm to identify all lumbar spine studies analyzing the influence of preoperative expectations on postoperative satisfaction and functional outcome. Two independent reviewers and a third independent mediator reviewed the literature and performed study screening, selection, methodological assessment, and data extraction using an objective protocol. Results Of 444 studies identified, 13 met the inclusion criteria. Methodological quality scores ranged from 59 to 100% with the greatest variability in defining patient characteristics and the methods of assessing patient expectations. Patient expectations were assessed in 22 areas, most frequently back and leg pain expectations and general expectations. Functional outcome was assessed by 13 tools; the most common were the visual analog scale, Oswestry Disability Index (ODI), and Short Form Health Survey (SF-36). Positive expectations for symptomatology, activity, general health, and recovery correlated with satisfaction. General expectations correlated with higher SF-36 Physical Subcomponent scores, better global function, and lower ODI outcome. Conclusions on the influence of the expectations for pain were limited due to the study heterogeneity, but the evidence suggests a positive correlation between the expectation and outcome for back and leg pain. Conclusions Positive expectations correlated significantly with short-term postoperative satisfaction and functional outcome, including higher SF-36 scores, earlier return to work, and decreased ODI scores. Future expectation-based investigations will benefit from implementation of the standardized methods of expectation, satisfaction, and outcome analysis discussed herein.