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78th Annual Meeting of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery

German Society of Oto-Rhino-Laryngology, Head and Neck Surgery

16.05. - 20.05.2007, Munich

Measuring the long incudal process: Precondition for developing a new Clip Piston for stapes surgery

Meeting Abstract

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German Society of Oto-Rhino-Laryngology, Head and Neck Surgery. 78th Annual Meeting of the German Society of Oto-Rhino-Laryngology, Head and Neck Surgery. Munich, 16.-20.05.2007. DŘsseldorf, K÷ln: German Medical Science; 2007. Doc07hno061

The electronic version of this article is the complete one and can be found online at:

Published: August 8, 2007

© 2007 Schimanski et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Introduction: Introduced in 2001, the Titanium Clip-Piston ÓWengen is an innovation: the elastic Clip for the first time safeguards a self-retaining, standardized position at the incus. Crimping, one of the most risky steps with stapes prostheses used before, was eliminated. After three years of use, the limitations of the Clip-Piston ÓWengen were established. When the incudal process was thin, the Clip was too loose. When the incudal process was thick, pushing the Clip-Piston onto the incus was not possible without prior manual distension. Consequently, a new Clip-Piston with a more favourable elasticity and stiffness had to be developed. As a precondition for the development, the cross sections of long incudal processes were taken in the application site of a stapes prosthesis.


A retrospective analysis of 275 surgical reports was done in order to establish the number of cases in which pushing the Clip-Piston ÓWengen was problematic due to the incus diameter.
Intraoperatively, two important incus diameters in 100 patients were taken: vertical axis (lateral-medial) and horizontal axis (anterior-posterior).


Evaluating the 275 operations performed by author 1 showed that in 14.5% of cases, pushing the Clip ÓWengen onto the incudal process was suboptimal, difficult or not possible.
Measuring the two diameters l-m and a-p of the long incudal process in the application site showed a variance of 0.5 to 0.9 mm. In 71 cases there was a vertical-oval cross section, in 13 cases there was a round cross section, and in 6 cases there was a horizontal-oval cross section.

Conclusion: Based on the results, the specifications profile for the design of a new Clip-Piston could be set up.