The Latarjet coracoid process transfer procedure: alterations in the neurovascular structures.

BACKGROUND

The Latarjet coracoid process transfer procedure is an established, reliable treatment for glenoid deficiency associated with recurrent anterior shoulder instability, but changes in neurovascular anatomy resulting from the procedure are a concern. The purpose of our cadaveric study was to identify changes in the neurovascular anatomy after a Latarjet procedure.

MATERIALS AND METHODS

We obtained 4 paired, fresh-frozen cadaveric forequarters (8 shoulders) from the Maryland State Anatomy Board. In each shoulder, we preoperatively measured the distances from the midanterior glenoid rim to the musculocutaneous nerve, axillary nerve, and axillary artery in 2 directions (lateral to medial and superior to inferior) and with the arm in 2 positions (0° abduction/neutral rotation; 30° abduction/30° external rotation), for a total of 12 measurements. We then created a standardized bony defect in the anterior-inferior glenoid, reconstructed it with the Latarjet procedure, and repeated the same measurements. Two examiners independently took each measurement twice. Inter-rater reliability was adequate, allowing pre-Latarjet measurements to be combined, averaged, and compared with combined and averaged post-Latarjet measurements by using paired Student t tests (significance, P ≤ .05).

RESULTS

We found (1) significant differences in the location of the musculocutaneous nerve in the superior-to-inferior direction for both arm positions, (2) notably lax and consistently overlapping musculocutaneous and axillary nerves, and (3) an unchanged axillary artery location.

CONCLUSIONS

The Latarjet procedure resulted in consistent and clinically significant alterations in the anatomic relationships of the musculocutaneous and axillary nerves, which may make them vulnerable to injury during revision surgery.