Measuring Resident Experience Level in an in-vitro Organic Tendon Repair Model

Abstract

Aim: Tendon injuries remain challenging to treat, and successful outcomes depend on surgical precision and experience. Simulation-based models are widely used to develop these skills. This study aimed to evaluate the effect of surgical experience on tendon repair quality using an in vitro chicken tendon model, focusing on tensile strength and repair time.
Material and Methods: The third deep flexors of 60 adult chicken feet were used in this study. Residents were divided into three groups by experience level as novice (Group A), intermediate (Group B), and experienced (Group C), with two residents per group. Each repaired approximately 10 chicken deep flexor tendons using a standardized technique. Repairs exceeding a 5-mm suture boundary or showing excessive bulk were excluded and repeated. Repair duration and ultimate tensile force (N) were recorded. Groups were compared to evaluate the effect of residents’ experience on operative time and tendon repair strength.
Results: Experienced residents achieved significantly higher tensile strength (34.55±6.51 N) compared to intermediate (24.65±6.53 N) and novice (14.91±4.50 N) groups (p<0.001). Pairwise comparisons revealed significant differences for all groups. Repair time showed a non-significant trend toward shorter duration with 324.75±80.42 s in the experienced group compared to the 385.50±108.41 s in Group A, 370.75±69.38 s in Group B (p=0.082).
Conclusion: Surgical experience was associated with significantly higher tendon repair strength, and repair time also showed a trend favoring experienced residents. The chicken tendon model provides a low-cost, accessible tool for objective training and assessment.

Keywords

• Injuries
• tendon
• gallus gallus domesticus
• residency
• medical
• medical education

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