P-063 Comparison of isokinetic dynamometer and strain gauge as measurement methods of abdominal wall strength in patients with abdominal hernia

Abstract

Abstract Aim The goal was to analyse trunk flexion strength in patients undergoing incisional hernia surgery, obtaining the data using both isokinetic dynamometer (gold standard for the measurement of the abdominal wall strenght) and strain gauge. Methods Observational cohort study, including patients with incisional hernia (July-December 2022). Collected data were demographic characteristics, clinical characteristics related with the hernia, and measures of the abdominal wall strength using an isokinetic dynamometer and a strain gauge. Comparative analysis was performed using Pearson correlation test adjusted for body composition parameters. Results 53 patients were enrolled (56,6% female) with a mean age of 57,42 age (SD 10,49). Mean BMI was 30,42 (SD 5,15), and mean maximum diameter of hernia defect was 6,75cm (SD 2,16). Bending force moment measurement was 80,23 N/m (SD 38,17). Results obtained with the strain gauge were: force peak with hip and knee flexion at 90° 171,1 N (SD 52,98), rate of force development (RFD) 523,29 N/s (SD 410,04). Adding 45° trunk rotation, peak force was 158,4 N (SD 42,76) and RFD 376,72 N/s (SD 288,74). Significant Pearson correlation indexes were found exceeding r= 0,641 for peak force and r= 0,305 for RFD (both at 90°), and r= 0,6 for peak force and r= 0,315 for RFD (both at 45°) when compared to isokinetic moment values. Conclusions In our group of study, we found a correlation between data obtained using isokinetic dynamometer and strain gauge. Further studies should analyze these associations controlling for other variables such as gender, age or hernia defect size.