Morphological and Functional Impact of Different Techniques on Limb Dissection: An Experimental Study in a Rat Model

Abstract

Background: Comparative studies on the effect of different tissue dissection techniques concerning adhesion, scar formation and functional impact on nerve and muscles are scarce, especially in orthopedic traumatic conditions.
Objectives: In the present experimental study, we aimed to investigate the impact of the choice of dissection technique on the peripheral nerve and surrounding tissues in a rat model of lower limb injury.
Materials and Methods: Forty adult female Wistar rats were divided into five groups (n = 8): In group 1, surgical blade was used to simulate sharp dissection; in group 2, a standard surgical forceps was used to simulate dissection with muscle contusion; In group 3, a small piece of compressed steel wool was used to simulate abrading during dissection; In group 4, extracorporeally minced muscles were used to simulate aggressive dissection; In group 5, a bipolar electrocoagulation instrument was used to simulate electrocautery dissection. During 3 weeks, the five groups were evaluated with functional assessment by toe out angle (TOA), morphological assessments by Petersen gross anatomical scale and histological assessment by scar formation index.
Results: The mean TOA was higher significantly in group 5 (P < 0.001). The largest mass of gross scar and the highest nerve adherence (grade 3) was detected in group 4 (P = 0.002). Scar index in all experimental groups was significantly higher than normal (P < 0.001). Group 4 showed the highest scar index (P = 0.000) and group 1 showed the lowest scar index.
Conclusions: Deep dissection with sharp cutting tools, results in low scar formation, tissue adhesion and subsequent indirect nerve injury. Electrocoagulation dissection may have side effects on adjacent nerves. Aggressive dissection, abrading during dissection and contusion should be avoided.