Success of ultrasound-guided versus landmark-guided arthrocentesis of hip, ankle, and wrist in a cadaver model.
OBJECTIVE
The objectives of this study were to evaluate emergency medicine resident-performed ultrasound for diagnosis of effusions, compare the success of a landmark-guided (LM) approach with an ultrasound-guided (US) technique for hip, ankle and wrist arthrocentesis, and compare change in provider confidence with LM and US arthrocentesis.


METHODS
After a brief video on LM and US arthrocentesis, residents were asked to identify artificially created effusions in the hip, ankle and wrist in a cadaver model and to perform US and LM arthrocentesis of the effusions. Outcomes included success of joint aspiration, time to aspiration, and number of attempts. Residents were surveyed regarding their confidence in identifying effusions with ultrasound and performing LM and US arthrocentesis.


RESULTS
Eighteen residents completed the study. Sensitivity of ultrasound for detecting joint effusion was 86% and specificity was 90%. Residents were successful with ultrasound in 96% of attempts and with landmark 89% of attempts (p=0.257). Median number of attempts was 1 with ultrasound and 2 with landmarks (p=0.12). Median time to success with ultrasound was 38s and 51s with landmarks (p=0.23). After the session, confidence in both US and LM arthrocentesis improved significantly, however the post intervention confidence in US arthrocentesis was higher than LM (4.3 vs. 3.8, p<0.001).


CONCLUSIONS
EM residents were able to successfully identify joint effusions with ultrasound, however we were unable to detect significant differences in actual procedural success between the two modalities. Further studies are needed to define the role of ultrasound for arthrocentesis in the emergency department.
Department of Emergency Medicine, Keck School of Medicine of USC, LAC+USC Medical Center, 1200 N. State Street, Room 1011, Los Angeles, CA 90033, United States. Electronic address: berona@usc.edu.
Kristin
K
Berona
Department of Emergency Medicine, Keck School of Medicine of USC, LAC+USC Medical Center, 1200 N. State Street, Room 1011, Los Angeles, CA 90033, United States.
Amin
A
Abdi
Department of Emergency Medicine, Keck School of Medicine of USC, LAC+USC Medical Center, 1200 N. State Street, Room 1011, Los Angeles, CA 90033, United States.
Michael
M
Menchine
Department of Emergency Medicine, Keck School of Medicine of USC, LAC+USC Medical Center, 1200 N. State Street, Room 1011, Los Angeles, CA 90033, United States.
Tom
T
Mailhot
Department of Emergency Medicine, Keck School of Medicine of USC, LAC+USC Medical Center, 1200 N. State Street, Room 1011, Los Angeles, CA 90033, United States.
Tarina
T
Kang
Department of Emergency Medicine, Keck School of Medicine of USC, LAC+USC Medical Center, 1200 N. State Street, Room 1011, Los Angeles, CA 90033, United States.
Dina
D
Seif
Department of Emergency Medicine, Keck School of Medicine of USC, LAC+USC Medical Center, 1200 N. State Street, Room 1011, Los Angeles, CA 90033, United States.
Mikaela
M
Chilstrom
D059925:Anatomic Landmarks; D000843:Ankle Joint / Q000000981:diagnostic imaging; D000069237:Arthrocentesis / Q000193:education / Q000295:instrumentation / Q000379:methods*; D002102:Cadaver; D002983:Clinical Competence / Q000592:standards*; D004635:Emergency Medicine / Q000193:education* / Q000379:methods / Q000592:standards; D006621:Hip Joint / Q000000981:diagnostic imaging; D006801:Humans; D007396:Internship and Residency / Q000592:standards*; D007719:Knee Joint / Q000000981:diagnostic imaging; D011446:Prospective Studies; D020377:Self Efficacy; D018084:Ultrasonography, Interventional / Q000379:methods / Q000592:standards*; D014955:Wrist Joint / Q000000981:diagnostic imaging
Arthrocentesis; Diagnostic testing; Education; Skills assessment/procedures; Ultrasound