Factors affecting width of the canine femorotibial joint space in nonweight-bearing radiographs

Caudocranial stifle radiographs with variations in positioning were made in two greyhound cadavers. Radiographs were repeated after each of three interventions: cranial cruciate desmotomy; release of the caudal horn of the medial meniscus; complete medial meniscectomy. The joint space on medial and lateral aspects of the joint was measured by a observer who was unaware of positioning or intervention. One dog had significantly wider joint space than the other (1.0 vs. 1.5mm). The lateral aspect of the joint space was wider than the medial aspect (1.7 vs. 0.7mm). Medial rotation of the stifle resulted in an increase of 0.4mm in width of the lateral joint space, whereas lateral rotation of the stifle reduced the lateral joint space by an average of 0.4mm. Decentering the X-ray beam had no significant effect on joint space width. Tension increased the width of the medial joint space by an average of 1.2mm and the lateral aspect by an average of 1.3mm. Cranial cruciate desmotomy resulted in an average 0.3mm increase in width of the joint space, and medial meniscectomy with an average 0.2mm reduction of the joint space. Although the femorotibial joint space was affected by iatrogenic stifle injuries and by medial or lateral rotation, these changes were less than the differences between the two dogs. Hence it seems unlikely that the small changes in joint space width associated with cruciate ligament desmotomy and medial meniscectomy will be detectable in clinical practice

SEM/EDS and optical microscopy analysis of microplastics

Microplastics are threatening materials directly produced by anthropogenic activities or resulting products of macroplastic degradation. Extended scientific research is being carried out on micro-/nanoplastics due to their relentless and increasing presence in the marine ecosystem with unpredicted ecological consequences. Thus, assessment of origin, life cycle, chemical nature, or composition of such polymer-based materials is essential and extremely valuable. The application of optical and electron (SEM/EDS) microscopy on the analysis and characterization of micro-/nanoplastics in aquatic environment is described in this chapter. It focuses on the benefits of using optical and electron imaging techniques for the detection and characterization of microplastics. Currently, these advanced imaging and analytical techniques have been essential in the categorization of such pollutants and other toxic substances that may be adsorbed at their surface. The emerging importance of SEM/EDS in the identification of microplastic-associated pollutants such as toxic metals is addressed. Suggestions for appropriate sample preparation and observation of these micromaterials under a microscope are briefly discussed. This chapter also highlights the importance of combining optical microscopy with spectroscopic techniques such as infrared and Raman scattering since it further enables precise chemical identification and analysis of microplastics. Ultimately, the collective use of SEM/EDS and optical microscopy associated with the spectroscopic analytical tools results in the most powerful strategy for accurate microplastic analysis.publishe