Spinal accessory nerve in a trapezius-splitting surgical approach.
To elucidate the safe limits for muscle-splitting incisions of the trapezius muscle, 25 cadaver shoulders were studied. To describe the position of the nerve distances were expressed as a percentage of the distance from the tips of the vertebral spinous processes to the lateral tip of the acromion. The spinal accessory nerve was found to run a vertical course medial and parallel to the vertebral border of the scapula. Three to six nerve branches (average 3.8) also ran a vertical course lying between 33% to 50% of the distance from the tips of the vertebral spinous processes to the lateral tip of the acromion. The most lateral branch lay an average at 44% distance and never beyond 50%. Muscle-splitting incisions are relatively safe in the lateral 50% of the muscle. In the medial half they are to be avoided or pursued with great caution.
Jobe
C M
CM
Department of Orthopaedic Surgery, Loma Linda University, School of Medicine, CA 92350, USA.
Kropp
W E
WE
Wood
V E
VE
D000055:Accessory Nerve / Q000033:anatomy & histology*; D006801:Humans; D066298:In Vitro Techniques; D018482:Muscle, Skeletal / Q000601:surgery*; D012016:Reference Values; D012785:Shoulder Joint / Q000033:anatomy & histology* / Q000601:surgery*