Objective Analysis of Image Distortion in Traditional versus Needle Arthroscopy

Introduction: Significant technological advancement has occurred in the field of needle arthroscopy in recent years. It was hypothesized that images collected via two needle arthroscopy (NA) systems would be more distorted than images collected using a traditional 2.4 mm arthroscopy (TA) system.

Materials and Methods: One TA and 2 NAs produced images of evenly spaced dots at 0° and 30° viewing angles. Deformity ratios and magnification percentages were calculated for each image and only compared if deemed significant via two-sample t-tests for populations with unequal variances.

Results: At a 0° viewing angle, NA-1 produced less magnification distortion and less deformity than TA. At a 30° viewing angle NA-1 produced more magnification distortion than TA; TA produced more deformity in the central field of view and less in the shallow and deep fields. Analysis of magnification distortion revealed no significant difference between NA-2 and TA at a 0° viewing angle, but TA produced less deformity distortion than NA-2. In the shallow field of view of images captured at a 30° viewing angle NA-2 produced more magnification distortion than TA and there was minimal difference between measurements of deformity in images from NA-2 and TA but NA-2 yielded less deformity.

Discussion/Conclusion: Magnification percentage and deformity ratios are emblematic of distortion in the size or the shape of an object in the arthroscopic field of view, respectively. High distortion systems should be avoided. The results of this study did not definitively confirm that needle arthroscopes produce more distorted images than traditional arthroscopes.

Acknowledgments: There was no proprietary interest or funding provided for this project.

Publication History

Article published online:
11 September 2023