Korean J Anesthesiol.  2008 Nov;55(5):570-574. 10.4097/kjae.2008.55.5.570.

Interscalene brachial plexus block: depth and angle from the skin insertion point to the brachial plexus and to C6-7 intervertebral foramen

• Kweon KS
• Yang HJ
• Gill HJ
• Seol JH
• Kim JH
• Lee JY
• Kim MK

• KMID: 2242996
• DOI: http://doi.org/10.4097/kjae.2008.55.5.570

Abstract

BACKGROUND
The angle and depth from the insertion point to the brachial plexus (BP) and C6-7 intervertebral foramen (IF) was examined to prevent critical complications of an interscalene brachial plexus block (ISBPB), such as an epidural or subdural injection of local anesthetics and spinal cord injury.
METHODS
Thirty patients (female = 12, male = 18), aged 20-64 years, undergoing shoulder or upper limb surgery were examined. ISBPB was performed at the interscalene groove intersecting the extended transverse line from the cricoid cartilage. A needle was then advanced towards the C6 transverse process (TP) and C6-7 IF under the C-arm fluoroscopic guidance. The depth and angle of the needle path intersecting the sagittal plane from the skin insertion point to BP, transverse process (TP) and IF were measured.
RESULTS
The mean depth of the needle from the insertion point to BP, TP and IF were 2.6 +/- 0.3 cm, 3.2 +/- 0.4 cm, 3.7 +/- 0.3 cm in the female patients, and 2.7 +/- 0.3 cm, 3.6 +/- 0.5 cm, 4.1 +/- 0.3 cm in the male patients. The mean angle of the needle path at the same point was 56.0 +/- 7.2o (range, 42.0-65.0degrees), 54.2 +/- 5.8degrees, 53.7 +/- 4.4degrees in the female patients, and 59.3 +/-8.3degrees (45.0-75.0degrees), 54.0 +/- 6.3degrees, 54.9 +/- 4.2degrees in male patients. There were significant differences in the depth from the skin to the TP and IF between males and females.
CONCLUSIONS
These findings are expected to provide a guideline for more accurate needle placement and successful block during ISBPB.

Keyword

brachial plexus; epidural space; interscalene block; intervertebral foramen; transverse process

MeSH Terms

Aged
Anesthetics, Local
Brachial Plexus
Cricoid Cartilage
Epidural Space
Female
Humans
Male
Needles
Shoulder
Skin
Spinal Cord
Upper Extremity
Anesthetics, Local