title: Factors influencing discomfort during anterior ultrasound-guided injection for hip arthrography.
abstract: BACKGROUND
  Although ultrasound (US)-guided injection techniques for magnetic resonance arthrography of the hip have been used with increasing frequency to diagnose internal joint derangements, little is known about patient tolerance, which is relevant information for patients. The objective of this study was to evaluate prospectively the association between possible influencing factors and discomfort felt during the performance of anterior US-guided injection techniques targeting the femoral head-neck junction during hip arthrography.
  
  
  METHODS
  Forty-four consecutive patients (21 women and 23 men; mean age, 41 years) undergoing magnetic resonance hip arthrography were sequentially assigned to receive injection alternating between fixed and freehand US-guided injection. Discomfort was assessed using a visual analog scale and relative ratings. Patient body mass index, extra-articular contrast leakage, the duration of the procedure, the needle advancement distance, and the fixed trajectory of the needle were assessed. Pearson's correlation coefficients and multiple logistic regression analysis were used to determine the association.
  
  
  RESULTS
  Puncture was successfully accomplished in all cases, and no relevant complications were reported. The only significant relationships were between discomfort and the time required for needle manipulation (r = 0.8) and fixed US-guided injection (r = 0.6; p < 0.001). Compared with the freehand technique, the fixed technique resulted in significantly less pain and took significantly less time to perform (p < 0.001). The procedure time during needle manipulation in the fixed US-guided injections (4.0 ± 0.9 seconds) was significantly less than that in the freehand US-guided injections (19.4 ± 17.6 seconds; p < 0.001). No significant relationships were found between discomfort and other parameters (r < 0.3, p > 0.05).
  
  
  CONCLUSIONS
  The procedure time appears to be the most important factor influencing patient discomfort. Fixed US-guided injection is a time-saving technique that alleviates procedure-related discomfort.
authors.affiliation: Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.
authors.forename: Yi-Chih
authors.initials: YC
authors.lastname: Hsu
authors.forename: Yu-Cheng
authors.initials: YC
authors.lastname: Wu
authors.forename: Hao-Lun
authors.initials: HL
authors.lastname: Kao
authors.forename: Ru-Yu
authors.initials: RY
authors.lastname: Pan
authors.forename: Meei-Shyuan
authors.initials: MS
authors.lastname: Lee
authors.forename: Guo-Shu
authors.initials: GS
authors.lastname: Huang
mesh_terms: D000328:Adult; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006621:Hip Joint / Q000000981:diagnostic imaging*; D006801:Humans; D007270:Injections, Intra-Articular / Q000009:adverse effects* / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000209:etiology*; D011446:Prospective Studies; D014463:Ultrasonography
chemical_list: D003287:Contrast Media
keywords: arthrography; hip; pain; ultrasound-guided injection