Level of the Subscapularis Split During Arthroscopic Latarjet.

Area of Science:

• Orthopedic Surgery
• Arthroscopy
• Shoulder Anatomy

Background:

• The Latarjet procedure is a common surgical treatment for anterior shoulder instability.
• Arthroscopic techniques aim to minimize invasiveness, but require precise dissection.
• The subscapularis muscle is a critical structure at risk during this approach.

Purpose of the Study:

• To determine the precise location of the subscapularis split created by an inside-out arthroscopic Latarjet technique.
• To assess the relationship between the switching stick's trajectory and the subscapularis muscle.
• To evaluate the risk of unintended high subscapularis splits.

Main Methods:

• An inside-out technique was employed to create arthroscopic subscapularis splits in 20 human cadaveric shoulders.
• Measurements of the switching stick's exit point relative to the subscapularis border and vessels were taken arthroscopically and via open dissection.
• Cadaveric specimens allowed for detailed anatomical evaluation.

Main Results:

• A significant proportion of subscapularis splits occurred in the upper third (12/20) or at the junction of the upper and middle thirds (3/20).
• Five splits were located in the middle third of the subscapularis.
• No splits were consistently achieved at the desired lower junction between the middle and lower thirds.

Conclusions:

• The inside-out technique for arthroscopic Latarjet, particularly when using a switching stick inserted from the posterior portal across the inferior glenoid, is associated with a high risk of subscapularis splitting.
• Surgeons should be aware of the potential for high subscapularis splits with this technique.
• Further refinement of the technique may be necessary to optimize subscapularis preservation.