Simulator/Soft Tissue - UGHE

UGHE Low-Cost Soft-Tissue Simulation Module

This page describes the development, construction, and educational outcomes of three low-cost soft-tissue procedure simulators for medical students in Rwanda. The models were created by the University of Global Health Equity (Butaro, Rwanda) in collaboration with the Program in Global Surgery and Social Change (Harvard Medical School) and Brigham and Women’s Hospital. Adapted from: Wittenberg RE, Bryce-Alberti M, et al. *BMC Medical Education* (2025) 25:1271.

Welcome to the Low-Cost Soft-Tissue Procedures Simulation Module. This module presents instructions and evidence from a study evaluating locally sourced, low-cost simulators designed to teach abscess drainage, subcutaneous nodule excision, and wound debridement to medical students in Rwanda.

Skin and soft-tissue conditions contribute substantially to surgical morbidity and mortality in low- and middle-income countries. In Rwanda, mortality from necrotizing soft-tissue infection exceeds 25%, and most cases require operative debridement. Despite this burden, undergraduate students rarely gain early exposure to these procedures in clinical settings.

Simulation-based training (SBT) enables students to practice key surgical skills safely and repeatedly using context-appropriate models. The University of Global Health Equity (UGHE), together with partners at Harvard Medical School’s Program in Global Surgery and Social Change (PGSSC) and Brigham and Women’s Hospital, designed this curriculum to address that gap.

Learners completing this module will be able to:

1. Explain the classification and management of common soft-tissue lesions, including incision and drainage principles, wound healing factors, and antibiotic use.
2. Describe the use of ultrasound in soft-tissue management, orient the probe, adjust depth, and identify basic subcutaneous structures.
3. Perform abscess incision and drainage—removing purulence and the abscess sac—with and without ultrasound guidance.
4. Excise a small, solid subcutaneous nodule with targeted incision and layered closure.
5. Debride a superficial wound to clean viable tissue and apply appropriate dressings.

• Incision and drainage technique
• Purulence evacuation and cavity exploration
• Tissue handling and blunt dissection
• Nodule excision and layered closure
• Wound debridement and dressing application
• Basic ultrasound guidance skills

• 30-minute introductory lecture on lesion evaluation, wound classification, and ultrasound.
• 3 hands-on stations (abscess drainage, nodule excision, wound debridement) with 4–8 students per group.
• “See one, do one, teach one” model following Miller’s Pyramid and Kirkpatrick Levels 1–2 of evaluation.
• 62 third-year medical students participated over three course iterations (2023–2024).

All materials were locally sourced in Rwanda and cost under $1.20 USD per model, requiring ≤ 5 minutes of active build time.

• 1 USD ≈ 1294 RWF (October 2023). Surgical instruments reused from clinical supply.*

1. Prepare the base: Cut a 10 × 10 cm sponge to represent subcutaneous tissue.
2. Abscess model: Fill a glove fingertip with lotion, tie it, and place between the sponge and gelatin layer. Cover with felt and tape (“skin”).
3. Nodule model: Replace the glove fingertip with a kidney bean to simulate a solid lesion.
4. Wound model: Slice a large sponge, insert vinyl scraps as debris, coat with red liquid latex to mimic bleeding tissue.
5. Mount: Fix each model on a cardboard or plastic tray base.
6. (Optional) Test the abscess model with a handheld ultrasound—purulent cavity is detectable under the surface.

• Participants: 62 third-year medical students
• Knowledge gain: 4.2 → 4.7 / 5 average (p = 0.01)
• Confidence gain: +1.7 (nodule), +1.4 (abscess), +1.7 (debridement), all p < 0.001
• Post-session confidence: ≥ 3.9 / 5 across all skills
• Realism ratings: 85–90% “somewhat” or “very representative”
• Average total material cost:** $3.43 USD for three models

Students described the sessions as *“fun and educative”* and appreciated the ultrasound component. The course improved procedural confidence for tasks rarely encountered in early clerkships.

• Refrigeration required for gelatin layers (limits transportability).
• Single-use models (cannot be reused after cutting or drainage).
• Ultrasound artifacts due to air in sponge layers reduce fidelity.
• Future goals: develop reusable, non-refrigerated materials and assess long-term clinical transfer (Kirkpatrick Level 4).

• Wittenberg RE, Bryce-Alberti M, Shimelash NZ, Masimbi O, Kratky LE, Thompson AA, et al. *Low-cost simulation models for soft-tissue procedures for medical student education in Rwanda.* BMC Medical Education. 2025; 25:1271. DOI

Developed by teams at the University of Global Health Equity, Program in Global Surgery and Social Change, and Brigham and Women’s Hospital. With gratitude to the UGHE Simulation & Skills Center and the participating Rwandan medical students.