HYDRO-DISSECTION VERSUS CONVENTIONAL SCALPEL DISSECTION OF THE PALMAR HAND IN CADAVERS: A RUBRIC-BASED COMPARISON OF STRUCTURAL INTEGRITY

Abstract

cBackground: The palmar hand contains the palmar aponeurosis, palmar vascular arches, digital neurovascular bundles, flexor tendons and joint capsules within a compact anatomical space. Their successful delineation depends on the dissection technique and the maintenance of tissue integrity during preparation. A rubric is a structured scoring tool that lists predefined criteria, each with clear performance levels, so that a dissection can be assessed against the same standard every time. The author used it to reduce subjective judgement and to give a consistent, reproducible measure of how accurately and clearly structures of the palmar hand were identified with each technique Objective: To compare conventional scalpel dissection with hydro-dissection (HDM) of the palmar hand using a customised anatomical dissection rubric to assess structural integrity. Methods: Thirty-five students each completed one palmar dissection: 17 using conventional scalpel dissection and 18 using HDM. Six anatomical regions—epidermal reflection, palmar aponeurosis, neurovascular structures, vascular arch, musculoskeletal structures and joint capsule—were scored from 1 to 5, producing a total structural integrity score ranging from 6 to 30. Dissection time, desiccation incidents, critical errors and student perception scores were also recorded. Groups were compared using the Mann–Whitney U test, with bootstrap 95% confidence intervals and Holm adjustment for multiple comparisons within the specified outcome families. Results: The total structural integrity score was higher in the HDM group than in the conventional scalpel group (24.61 ± 1.42 versus 19.35 ± 1.58; mean difference 5.26, 95% CI 4.30–6.23; p < 0.001). Five of the six anatomical regions favoured HDM. The largest differences were observed in the vascular arch, joint capsule and musculoskeletal regions. No significant difference was observed for the palmar aponeurosis (difference −0.17, 95% CI −0.64 to 0.34). HDM was associated with fewer desiccation incidents and critical errors and higher student perception scores. However, the mean dissection time was 67.8 minutes longer with HDM (95% CI 62.0–73.4). Conclusion: In this sample, hydro-dissection was associated with higher structural integrity scores, fewer recorded desiccation incidents and critical errors, and more favourable student perceptions than conventional scalpel dissection. These outcomes were accompanied by substantially longer dissection times. The findings are preliminary and require confirmation through larger studies with blinded, multi-rater assessment.