Annals of Biomedical Engineering

, Volume 46, Issue 5, pp 726–735 | Cite as

UROKIN: A Software to Enhance Our Understanding of Urogenital Motion

  • Catriona S. Czyrnyj
  • Michel R. Labrosse
  • Ryan B. Graham
  • Linda McLean


Transperineal ultrasound (TPUS) allows for objective quantification of mid-sagittal urogenital mechanics, yet current practice omits dynamic motion information in favor of analyzing only a rest and a peak motion frame. This work details the development of UROKIN, a semi-automated software which calculates kinematic curves of urogenital landmark motion. A proof of concept analysis, performed using UROKIN on TPUS video recorded from 20 women with and 10 women without stress urinary incontinence (SUI) performing maximum voluntary contraction of the pelvic floor muscles. The anorectal angle and bladder neck were tracked while the motion of the pubic symphysis was used to compensate for the error incurred by TPUS probe motion during imaging. Kinematic curves of landmark motion were generated for each video and curves were smoothed, time normalized, and averaged within groups. Kinematic data yielded by the UROKIN software showed statistically significant differences between women with and without SUI in terms of magnitude and timing characteristics of the kinematic curves depicting landmark motion. Results provide insight into the ways in which UROKIN may be useful to study differences in pelvic floor muscle contraction mechanics between women with and without SUI and other pelvic floor disorders. The UROKIN software improves on methods described in the literature and provides unique capacity to further our understanding of urogenital biomechanics.


Stress urinary incontinence Pelvic floor muscles Maximum voluntary contraction Urogenital kinematics 



The authors would like to acknowledge Kevin Varette, P.T. for his contributions to the data acquisition. This work was supported by the Canadian Institutes of Health Research (CIHR-IRSC 0076433) and the Natural Sciences and Engineering Research Council of Canada (NSERC 05256).


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Copyright information

© Biomedical Engineering Society 2018

Authors and Affiliations

  1. 1.Department of Mechanical EngineeringUniversity of OttawaOttawaCanada
  2. 2.Department of Mechanical EngineeringUniversity of OttawaOttawaCanada
  3. 3.School of Human KineticsUniversity of OttawaOttawaCanada
  4. 4.School of Rehabilitation SciencesUniversity of OttawaOttawaCanada

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