Sonographically guided tendon sheath injections are more accurate than blind injections: implications for trigger finger treatment.
OBJECTIVE
Trigger finger is frequently treated with tendon sheath injections. This cadaveric study evaluated the accuracy and safety of blind and sonographically guided tendon sheath injections. To our knowledge, a study that precisely mapped the locations of material injected into the tendon sheath has not been reported previously.


METHODS
A total of 40 fingers (excluding thumbs) of 5 fresh cadavers were used. Methylene blue dye was injected into the flexor tendon sheath using either a blind or sonographically guided injection technique (20 fingers for each technique). The location of the dye was then determined via dissection.


RESULTS
Dye was observed only in the tendon sheath (ie, optimal outcome) in 70% of sonographically guided injections and 15% of blind injections (P = .001). Dye was observed in the tendon proper (ie, unsafe outcome) in 30% of blind injections and 0% of sonographically guided injections (P = .02).


CONCLUSIONS
We found that sonographically guided tendon sheath injections were more accurate and may be potentially safer than blind injections. These findings suggest that sonographically guided injections should be considered over blind injections when treating trigger finger.
Department of Orthopedic Surgery, Korea University College of Medicine, Seoul, Korea.
Dae-Hee
DH
Lee
Seung-Beom
SB
Han
Jong-Woong
JW
Park
Soon-Hyuck
SH
Lee
Kwan-Woo
KW
Kim
Woong-Kyo
WK
Jeong
D000368:Aged; D002102:Cadaver; D005385:Fingers; D005938:Glucocorticoids / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D066298:In Vitro Techniques; D007267:Injections / Q000009:adverse effects / Q000379:methods; D008297:Male; D008751:Methylene Blue; D008875:Middle Aged; D013710:Tendons / Q000000981:diagnostic imaging*; D052582:Trigger Finger Disorder / Q000000981:diagnostic imaging / Q000188:drug therapy*; D018084:Ultrasonography, Interventional
D005938:Glucocorticoids; D008751:Methylene Blue