MR arthrography of the shoulder: do we need local anesthesia?
OBJECTIVE
To assess pain intensity with and without subcutaneous local anesthesia prior to intraarticular administration of contrast medium for magnetic resonance arthrography (MRa) of the shoulder.


METHODS
This single-center study was conducted after an IRB waiver of authorization, between January 2010 and December 2012. All patients provided written, informed consent for the procedure. Our prospectively populated institutional database was searched, based on our inclusion criteria. There were 249 outpatients (178 men and 71 women; mean age, 44.4 years ± 14.6; range, 15-79) who underwent MRa and were enrolled in this study. Patients were excluded if they had received surgery of the shoulder before MRa, had undergone repeated MRa of the same shoulder, and/or had undergone MRa of both shoulders on the same day. Patients were randomly assigned into one of three groups. Patients in group A (n=61) received skin infiltration with local anesthesia. Patients in control group B (n=92) and group C (n=96) did not receive local anesthesia. Pain levels were immediately assessed after the injection for MRa using a horizontal visual analog scale (VAS) that ranged from 0 to 10. To compare the pain scores of the three groups for male and female patients, a two-way analysis of variance was used. A p-value equal to or less than 0.05 was considered to indicate a significant result.


RESULTS
Patients who received local anesthesia (group A) showed a mean pain level on the VAS of 2.6 ± 2.3. In patients who did not receive local anesthetics (groups B and C), a mean pain level on the VAS of 2.6 ± 2.2 and 2.7 ± 2.4 were detected, respectively. Between the three groups, no statistically significant difference in pain intensity was detected (p=.960). There were significant differences in subjective pain perception between men and women (p=.009). Moreover, the sex difference in all three groups was equal (p=.934).


CONCLUSIONS
Local anesthesia is not required to lower a patient's pain intensity when applying intra-articular contrast media for MR arthrography of the shoulder. This could result in reduced costs and a reduced risk of adverse reactions, without an impact on patient comfort.
Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna (AKH), Waehringer-Guertel 18-20, 1090 Vienna, Austria. Electronic address: claudio.spick@meduniwien.ac.at.
Claudio
C
Spick
Diagnostikum Graz-Südwest, Weblinger Guertel 25, 8054 Graz, Austria.
Dieter H M
DHM
Szolar
Diagnostikum Graz-Südwest, Weblinger Guertel 25, 8054 Graz, Austria.
Pia
P
Reittner
Diagnostikum Graz-Südwest, Weblinger Guertel 25, 8054 Graz, Austria.
Klaus W
KW
Preidler
Diagnostikum Graz-Südwest, Weblinger Guertel 25, 8054 Graz, Austria.
Manfred
M
Tillich
D000293:Adolescent; D000328:Adult; D000368:Aged; D000779:Anesthetics, Local / Q000008:administration & dosage; D003287:Contrast Media / Q000008:administration & dosage / Q000009:adverse effects; D005260:Female; D006801:Humans; D007270:Injections, Intra-Articular / Q000009:adverse effects; D008012:Lidocaine / Q000008:administration & dosage*; D008279:Magnetic Resonance Imaging / Q000009:adverse effects* / Q000379:methods*; D008297:Male; D008536:Meglumine / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D008875:Middle Aged; D009942:Organometallic Compounds / Q000008:administration & dosage* / Q000009:adverse effects*; D010147:Pain Measurement / Q000187:drug effects; D020069:Shoulder Pain / Q000175:diagnosis* / Q000209:etiology*; D016896:Treatment Outcome; D055815:Young Adult
D000779:Anesthetics, Local; D003287:Contrast Media; D009942:Organometallic Compounds; C064572:gadobenic acid; D008536:Meglumine; D008012:Lidocaine
Arthrography; Local anesthesia; MR arthrography; Pain; Shoulder