Bacterial Load Studies: Traditional vs. ActivArmor casts

In this post, we are going to discuss the bacterial adherence to the different types of casting materials. The following excerpt was taken from the American Association for Hand Surgery “Bacterial Adherence to Casting Materials”[1]

INTRODUCTION: This study aims to evaluate the bacterial adherence and ease of decontamination of commonly used casting materials including Plaster, Fiberglass, Plastic (3D printed), and Waterproof liner. We hypothesize that there will be a significant decrease in bacterial counts remaining on the material after washed with soap solutions compared to a saline control, especially in non-porous waterproof material.

MATERIALS & METHODS: The minimal inhibitory concentration of two phosphate-free soaps that achieved total bacterial kill off was determined. The anti-bacterial ingredient in detergent #1 and #2 was triclosan 0.10% and lactic acid, respectively. After inoculation with Staphylococcus aureus, scanning electron micrographs were performed. Using one of two soaps or saline (PBS), the materials were washed. Each material was run in 18 replicates: 6 with PBS, 6 with detergent #1, and 6 with detergent #2. Materials were then washed with PBS and sonicated to remove the remaining bacteria on the materials’ surface and cultured. Colony forming unit (CFU) counts were recorded. The washing protocol was repeated for a total of 3 trials.

RESULTS: Washing with either soap significantly decreased the remaining CFU for all materials studied. The mean remaining CFU of Plaster, Plastic, and Fiberglass after washings with either soap was compared to one another. Plaster material partially decompensated in the washing process. The mean remaining CFU of Plastic showed to be significantly less than that of Plaster and Fiberglass when washed with detergent #1. No statistical significance was observed between remaining CFU of the materials washed with detergent #2.

CONCLUSION: The current study demonstrates that soap solutions compared to a saline control are significantly more effective at decreasing the bacterial load on cast material surfaces that are waterproof (Plastic and Fiberglass). 3D printed plastic cast material when washed with detergent #1 is superior in decontamination of bacteria to other materials observed. While no objective data exists to guide the choice of casting material, the current study suggests that this decision in addition to washing casts may play a role in decreasing wound infection in a clinical setting.

[1] Joseph E Massaglia, D.O.1, Cory Lebowitz, D.O.1, Keith Fitzgerald, B.S.2, Noreen Hickok, Ph.D. 2, Pedro K Beredjiklian, MD3 and Michael Rivlin, M.D.4, (1)Rowan School of Osteopathic Medicine, Stratford, NJ, (2)Thomas Jefferson University, Philadelphia, PA, (3)Rothman Orthopaedic Institute, Philadelphia, PA, (4)Rothman Institute, Philadelphia, PA

How 3D Printed Casts Reduce Bacterial Loads

Per the aforementioned study, 3D printed casts had a decontamination that far exceeded the other materials that are used in casting. The bacterial colonization that resulted from the patients who wore traditional casts was much higher because the casts are not sanitizable and trap moisture and bacteria. Whereas the patients who wore the ActivArmor cast showered and sanitized around and underneath their casts which reduces the chances of skin maceration or trapped bacteria.  

In addition to providing a cast that is washable, sanitizable and sterilizable, ActivArmor’s custom 3D printed casts are made from ABS plastic. Unlike many of the materials used for traditional casting, like cotton or lycra, ABS plastic is non-reactive to the skin.

Real-World Application

Improving cast hygiene through the use of ActivArmor’s materials and design is a game changer for professionals providing medical care and in the food handling industry. With the bacterial loads that colonize from traditional casts, professionals could become a public hazard due to increased chances for viral transmission. However, since ActivArmor’s casts are sanitizable, professionals who wear 3D printed casts can continue performing their daily duties at work and at home without health transmission concerns. 

If you’d like to provide your patients with ActivArmor’s sanitizable casts click the button below to learn more.