ISAKOS: 2023 Congress in Boston, MA USA

2023 ISAKOS Biennial Congress ePoster

 

A Comparative Study of The Insertion Angles of Guidewire Between Pectoralis Major and Anteroinferior Portals in Modified Arthroscopic Bristow Procedure

Sho Yamauchi, MD, Nagoya JAPAN
Tetsuya Takenaga, MD, PhD, Nagoya, Aichi JAPAN
Atsushi Tsuchiya, MD, PhD, Nagoya, Aichi JAPAN
Satoshi Takeuchi, MD, PhD, Toyohashi JAPAN
Jumpei Inoue, MD, Nagoya, Aichi JAPAN
Hideki Murakami, MD, PhD, Nagoya JAPAN
Masahito Yoshida, MD, PhD, Nagoya, Aichi JAPAN

Department of Orthopaedic Surgery, Nagoya City University Graduate School of Medical Sciences, Nagoya, Mizuhoku Mizuho-chou Kawasumi1, JAPAN

FDA Status Not Applicable

Summary

This cadaveric study compared insertion angles of guidewire to fix coracoid fragment between pectoralis major portal and anteroinferior portal in the modified arthroscopic Bristow procedure and clarified pectoralis major portal enables surgeons to insert guidewire in smaller angle to the glenoid articular surface, which is advantageous for the coracoid bone union.

ePosters will be available shortly before Congress

Abstract

Introduction

The Bristow procedure was firstly described in 1958 to address recurrent anterior instability with significant glenoid bone loss. This procedure has been widely adopted and modified. Recently arthroscopic Bristow procedures has gained popularity. During the procedure, coracoid fragment is fixed to the glenoid neck via anteroinferior portals (AIP) or pectoralis major portals (PMP).

Purpose

The purpose of this study was to compare the insertion angles of guidewire between through PMP and AIP in modified arthroscopic Bristow procedure.

Materials And Methods

Eight cadaveric shoulders (5 right and 3 left shoulders, 2 men and 3 women) were included. The mean age at death was 90.2 years (84-96 years). Cadavers were placed in beach-chair position, and modified arthroscopic Bristow procedure was performed. Following the osteotomy of the coracoid tip, PMP (7 cm medial and 7 cm distal from the coracoid process) and AIP (5 cm distal from the coracoid process along the conjoint tendon) were created. A guidewire was inserted at the 4 o’clock position and 5 mm medial from the glenoid edge through PMP and AIP. Fluoroscopy was used to define two different angles of guidewires on radiographs: true anteroposterior view of the glenohumeral joint (anterior–posterior tilt of scapula was adjusted for the coracoidal base to be seen as an ellipse), and axial view. The angles between the guidewire and the glenoid articular surface were measured using ImageJ.
Paired t test was used to compare the angles with significance set at p<0.05.

Results

The insertion angles against the glenoid articular surface were significantly smaller in PMP group both in the anteroposterior view (19.5±14.9 degrees in PMP group, and 50.3±8.7 degrees in AIP group) and axial view (16.2±14.3 degrees in PMP group, and 39.5±4.9 degrees in AIP group).

Conclusion

This study clarified that PMP enabled surgeons to insert guidewires in smaller angles against the glenoid articular surface when fixing coracoid fragment. Lower union rate of the coracoid fragment was reported when guidewire was tilted medially more than 25 degrees. In our study, use of PMP allowed surgeons to insert guidewire smaller than 25 degrees in both anteroposterior and axial view. Therefore, in terms of the coracoid fragment union, PMP can be useful in modified arthroscopic Bristow procedure.