Minimum Incision Size Required for Implantation: A Comparison of Medtronic InterStim X™ and Axonics F15® Pulse Generator Dimensions

² Department of Obstetrics and Gynecology and East Valley Obstetrics and Gynecology Residency Program, School of Medicine, Creighton University, Phoenix, Arizona, United States of America

³ Arizona College of Osteopathic Medicine, Midwestern University, Glendale, Arizona, United States of America

⁴ Marchand Institute for Minimally Invasive Surgery, Mesa, Arizona, United States of America

STI 2026, 46(1), 11–15; https://doi.org/10.36922/sti.0240

Received: 7 August 2025 | Revised: 16 November 2025 | Accepted: 18 November 2025 | Published online: 15 January 2026

© 2026 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )

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Abstract

Background: Sacral neuromodulation (SNM) is a guideline-recommended therapy for a variety of bladder and bowel dysfunctions. This study compares the physical dimensions of two SNM implantable pulse generators—Medtronic's InterStim X and Axonics's F15—and examines the potential clinical implications.

Methods: We extracted height, length, thickness, and weight data from manufacturer specifications and interpreted these in the context of the SNM surgical technique.

Results: Our analysis showed that the devices are similar in overall size (InterStim X: 44 × 51 × 8 mm, 22 g, ~12.5 cc; Axonics F15: 39 × 53 × 6.7 mm, 24.5 g, ~10 cc). Despite these similarities, other metrics can affect the minimum incision size required for implantation.

Conclusion: Overall, the two devices have comparable dimensions; however, InterStim X requires a smaller incision size for implantation than the Axonics F15.

Keywords

Axonics F15

Device dimensions

Implantable pulse generator

InterStim X

Minimum incision size required for implantation

Sacral neuromodulation

Surgical technique

References

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Surgical Technology International, Electronic ISSN: 1090-3941 Published by AccScience Publishing