Incidental Findings of Appendiceal Diverticulitis Presenting as Acute Appendicitis.

Diverticulosis of the appendix (DA) is a rare pathological finding that clinically imitates acute appendicitis and is most commonly found in adult males with chronic abdominal pain. It has a higher rate of perforation compared to acute appendicitis (84% vs 12%, P<0.01), and is consequently associated with a higher rate of mortality. Appendiceal diverticulitis has been found to have a significant association with incidental appendiceal neoplasms, therefore elective prophylactic appendectomy is recommended to prevent the risk of complications and to rule out the possibility of a coexisting neoplasm. Meticulous gross examination in addition to thorough histological examination of the entire appendectomy specimen by pathologists is essential in order to identify diverticula. We present two female patients with signs and symptoms consistent with acute appendicitis, they were found to have appendiceal diverticulitis on pathologic evaluation.

Intraoperative and biomechanical studies of human vastus lateralis and vastus medialis sarcomere length operating range.

The vast majority of musculoskeletal models are not validated against primary experimental data. Conversely, most human experimental measurements are not explained theoretically using models to provide a mechanistic understanding of experimental results. Here we present a study with both primary human data and primary modeling data. Intraoperative sarcomere length was measured on the human vastus lateralis (VL) and vastus medialis (VM) muscles (n = 8) by laser diffraction. These data were compared to a biomechanical model based on muscle architecture and moment arms obtained independently from cadaveric specimens (n = 9). Measured VL sarcomere length ranged from about 3.2 µm with the knee flexed to 45° to 3.8 µm with the knee flexed to 90°. These values were remarkably close to theoretical predictions. Measured VM sarcomere length ranged from 3.6 µm with the knee flexed to 45° to 4.1 µm with the knee flexed to 90°. These values were dramatically longer than theoretical predictions. Our measured sarcomere length values suggest that human vasti may have differing functions with regard to knee extension and patellar stabilization. This report underscores the importance of validating experimental data to theoretical models and vice versa.