BME Design Team’s innovation aims to improve patient outcomes after peripheral nerve damage

The current method requires that neurosurgeons physically pull the injured nerve from the wound site for assessment using a device about the size of an extra-long pencil with large, insulated metal hooks.

But the lifting of the nerve increases the risk of further injury and can distort the electrode-recorded signal, making it difficult for the surgical team to determine if surgery is necessary. “This approach can have irreversible consequences on the patient outcome,” said Riemann.

To understand how peripheral nerve injury is assessed and the drawbacks of the current process, the Design Team observed the neurosurgical procedure at Johns Hopkins Hospital. They collected data on the procedure, including the timing and sequence of each step, the operating room floor layout, and the instruments used.

The team also received a grant from the Biomedical Engineering Innovation, Design, and Entrepreneurship Alliance (BME IDEA), to travel to Santiago, Chile to visit La Pontificia Universidad Católica de Chile. There the team was able to tap into the technical expertise of faculty and partners at TrainFES, a local startup company focused on neurorehabilitation.

Seeing how the faculty in Chile and TrainFES tackled similar engineering challenges helped the team develop their final solution: an electrode design with an improved nerve securement feature that has a “sandwich” or “chopstick”-like style that makes the procedure less invasive for patients. The device handle also has an index finger-adjusted linear sliding mechanism to open and close the electrode clamp around the nerve. Their solution allows the procedure to be completed by one surgeon as opposed to several, which is the current process.

A major challenge was making an easy-to-use device; especially because — as their clinical mentor Dr. Allan Belzberg advised them — the task of isolating and assessing a peripheral nerve in the surgical field is as challenging as trying to wrap the device around wet spaghetti inside of a purse. Their final design “heavily considers the end user more prominently in all steps of the design process,” said Riemann.

Impacted by this experience, Riemann is now pursuing a MD/PhD at The University of Colorado Anschutz Medical Campus and plans to focus on translational medical device development.

“Design Team experience was pivotal in my understanding of where my ambitions, interests, and aptitudes intersect, leading to the beginning of my MD/PhD training. It has also given me a much deeper appreciation for each of these respective fields, and especially for the importance of interdisciplinary collaboration that can yield the most impactful solutions to real-world needs,” Riemann said.

Additional co-authors from Hopkins BME include seniors Jack Coursen, Xin-Hua (Katie) Liang and Laura Elena Porras; master’s student Bryan Sabogal; graduate student Lily Zhu; alums Christian Guaraca Engr ’23 (MSE), Samantha Weed Engr ’22; and Constanza Miranda, associate teaching professor.

Allan Belzberg, professor of neurological surgery, Matthias Ringkamp, associate professor of neurological surgery, and Gang Wu, assistant professor of neurological surgery, served as authors and clinical mentors that played a critical role in the making the project possible.