Accuracy of needle placement in cadavers: non-guided versus ultrasound-guided.
OBJECTIVE
To compare the accuracy rates of non-guided vs. ultrasound-guided needle placement in four lower limb muscles (tibialis posterior, peroneus longus, and short and long heads of the biceps femoris).


METHODS
Two electromyographers examined the four muscles in each of eight lower limbs from four fresh frozen cadavers. Each electromyographer injected an assigned dye into each targeted muscle in a lower limb twice (once without guidance, another under ultrasound guidance). Therefore, four injections were done in each muscle of one lower limb. All injections were performed by two electromyographers using 18 gauge 1.5 inch or 24 gauge 2.4 inch needles to place 0.5 mL of colored acryl solution into the target muscles. The third person was blinded to the injection technique and dissected the lower limbs and determined injection accuracy.


RESULTS
A 71.9% accuracy rate was achieved by blind needle placement vs. 96.9% accuracy with ultrasound-guided needle placement (p=0.001). Blind needle placement accuracy ranged from 50% to 93.8%.


CONCLUSIONS
Ultrasound guidance produced superior accuracy compared with that of blind needle placement in most muscles. Clinicians should consider ultrasound guidance to optimize needle placement in these muscles, particularly the tibialis posterior.
Department of Rehabilitation Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea.
Jae Sung
JS
Yun
Department of Rehabilitation Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea.
Min Jae
MJ
Chung
Department of Rehabilitation Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea.
Hae Rim
HR
Kim
Department of Rehabilitation Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea.
Jae In
JI
So
Department of Rehabilitation Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea.
Jung Eun
JE
Park
Department of Rehabilitation Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea.
Hyun Mi
HM
Oh
Department of Rehabilitation Medicine, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea.
Jong In
JI
Lee
Biceps femoris; Cadaver; Electromyography; Tibialis posterior; Ultrasound