1998 Volume 22 Issue 2 Pages 267-269
We studied the mechanism of musculocutaneous neuropathy associated with the Boytchev procedure in cadavers.
(Materials and methods)
The subjects we re 21 adult cadavers (42 shoulders) for anatomical study. The distance from the anterior end of the coracoid process to the site of the entry of the musculocutaneous nerve trunk into the coracobrachialis muscle was determined as A, the distance to the insertion of the short head of the biceps among the nerve branches as B, and the distance to the coracobrachialis insertion site as C. Then, the coracoid process (served to measure the insertion of the short head of the biceps and that of the coracobrachialis) was returned to its original position beneath the full-thickness of the subscapularis muscle by the original Boytchev method, and the distance from the anterior end of the coracoid process to the lower margin of the subscapularis was determined as D.
(Results)
A was 47.5±13.2mm, B was 30.1±6.2mm, C was 33.9±7.5mm and D was 33.3±5.3mm. A was below D, i. e., the entry site of the musculocutaneous nerve trunk was above the lower margin of the subscapularis muscle, and entrapment of the musculocutaneous nerve trunk by the subscapularis muscle was present in nine shoulders (21.4%).
(Discussion)
In patients where the site of the entry of the musculocutaneous nerve trunk into the coracobrachialis muscle is at a higer position than the lower margin of the subscapularis, it appears necessary to take technical precautions such as passing the severed coracoid process through the lower one third of the belly of the subscapularis.
