Validity of a pump-perfused chicken thigh model for microsurgical training.

BACKGROUND

Microsurgical training has traditionally relied on live animal models. While these offer high anatomical and functional fidelity, their use raises increasing ethical, logistical, and economic concerns and alternatives are needed.

METHODS

We conducted a prospective observational study to assess the subjective and objective validity of a pump-perfused chicken thigh model for microsurgical training. Forty-five residents and surgeons were categorized by microsurgical experience. Thirteen participants underwent motion analysis and blinded video-based scoring. All participants performed arterial end-to-end anastomoses. Face and content validity were evaluated by experienced participants using Likert-scale questionnaires, while construct validity was assessed by comparing operative performance, Stanford Microsurgery and Resident Training scoring (SMaRT) and motion parameters across experience levels.

RESULTS

Face and content validity scores were high, with median values of 7.9 (IQR 7.3-8.3) and 8.8 (IQR 6.4-9.0), respectively. Construct validity was demonstrated by significant improvements with experience, including faster operative times (p = 3.05×10-6, ε∼0.59), higher success rates and fewer leaks (p = 1.41×10-5, V(Cramer)∼0.56). Experts displayed smoother, more stable hand movements (lower jerk, tremor, and rotational instability); SMaRT scores effectively distinguished experts from non-experts (p = 0.0014 (r = 1)), and correlated moderately with motion metrics, suggesting complementary roles of expert video assessment and motion analysis in evaluating microsurgical performance. Qualitative differences in motion profiles and gesture structure were apparent between novice and expert participants.

CONCLUSION

The perfused chicken thigh model is a realistic and ethical alternative for microsurgical training with robust face, content and construct validities. Motion analysis might provide an objective complement to expert video-based assessment, suggesting its interest in structured training programs.