Acta Scientific Orthopaedics (ISSN: 2581-8635)

Research Article Volume 5 Issue 6

Understanding Proximal Ulna Anatomy on Fluoroscopic Images

Sean M Mitchell1*, Anna Y Babushkina2, Andrew S Chung3 and Scott G Edwards4

1Department of Orthopedic Surgery, The Ohio State University Wexner Medical Center, Columbus, OH, USA
2Mendelson Kornblum Orthopedics, Warren, Michigan, USA
3Department of Orthopedic Surgery, Mayo Clinic, Scottsdale, Arizona, USA
4The CORE Institute, Phoenix, Arizona, USA

*Corresponding Author: Sean M Mitchell, Department of Orthopedic Surgery, The Ohio State University Wexner Medical Center, Columbus, OH, USA.

Received: March 18, 2022; Published: May 09, 2022


Purpose: The three-dimensional anatomy of the proximal ulna can be difficult to interpret with standard intraoperative fluoroscopy. Without appropriate visualization, surgeons risk placing implants in suboptimal locations during fracture fixation of the proximal ulna. The purpose of this study was to delineate the borders of proximal ulnar anatomy, specifically, the trochlear ridge and the medial and lateral facets, and to provide measurements to assist surgeons with navigation of its complex anatomy.

Methods: We analyzed ten fresh-frozen cadaveric elbows: five female and five male specimens, with diverse ages and heights. Utilizing novel reference points, the center of the trochlea and the intersection of the ulnar axis and a perpendicular plumb line from the coronoid tip, we recorded measurements to adjacent anatomical landmarks.

Results: The distances from the center of the trochlea to the trochlear ridge, the medial facet, and lateral facet from the center of the trochlea as measured off of a custom reference line were 10.2 mm (95% confidence intervals 9.7 to 10.6 mm), 13.6 mm (95% CI; 12.4 to 14.8 mm), and 11.2 mm (95% CI; 10.9 to 11.5 mm), respectively. When evaluating our referencing technique, we found inter-observer and intra-observer reliabilities to be dependable at 0.85 to 0.98 for all measurements, respectively.

Conclusions: This cadaveric study provides simple radiographic parameters that should be considered when placing implants about the trochlear notch of the proximal ulna to avoid aberrant hardware placement.

Keywords: Proximal Ulna Anatomy; Intraoperative Fluoroscopy; Elbow Joint; Elbow Joint Surgery; Ulna Surgery; Basic Science Study


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Citation: Sean M Mitchell., et al. “Understanding Proximal Ulna Anatomy on Fluoroscopic Images". Acta Scientific Orthopaedics 5.6 (2022): 28-33.


Copyright: © 2022 Sean M Mitchell., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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