title: Application of Pain Quantitative Analysis Device for Assessment of Postoperative Pain after Arthroscopic Rotator Cuff Repair.
abstract: OBJECTIVE
  The PainVision™ system was recently developed for quantitative pain assessment. Here, we used this system to evaluate the effect of plexus brachialis block on postoperative pain after arthroscopic rotator cuff repair.
  
  
  METHODS
  Fifty-five patients who underwent arthroscopic rotator cuff repair were included in this study. First 26 cases received no plexus brachialis block (control group), and the next 29 cases received the plexus brachialis block before surgery (block group). Patients completed the visual analog scale at 4, 8, 16, and 24 hours after surgery, and the intensity of postoperative pain was assessed with PainVision™ at 16 hours. The postoperative use of non-steroidal anti-inflammatory agents was also recorded.
  
  
  RESULTS
  The pain intensity at 16 hours after surgery assessed by PainVision™ was significantly lower in the block group than in the control group (block, 252.0 ± 47.8, control, 489.0 ± 89.1, P < 0.05). However, there were no differences in the VAS values at 16 hours between the 2 groups (block, 4.3 ± 0.6, control, 5.7 ± 0.4, P = N.S.). The pain intensity and VAS at 16 hours after surgery were highly correlated (r = 0.59, P = 0.006 in the block group and r = 0.62, P = 0.003 in the control group). The effect size of the assessment by PainVision™ was bigger than that of VAS (r=0.31 in VAS and 0.51 in Pain vision).
  
  
  CONCLUSIONS
  The PainVision™ system could be useful to evaluate postoperative pain because it enables the quantification and comparison of pain intensity independent of individual pain thresholds.
authors.affiliation: Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Mifune
authors.affiliation: Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.
authors.forename: Atsuyuki
authors.initials: A
authors.lastname: Inui
authors.affiliation: Department of Orthopaedic Surgery, Kobe Rosai Hospital, Kobe, 650-0017, Japan.
authors.forename: Issei
authors.initials: I
authors.lastname: Nagura
authors.affiliation: Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Sakata
authors.affiliation: Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Muto
authors.affiliation: Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Harada
authors.affiliation: Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Takase
authors.affiliation: Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kurosaka
authors.affiliation: Department of Orthopaedic Surgery, Kobe University Graduate School of Medicine, Kobe, 650-0017, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kokubu
keywords: Analysis device; arthroscopic rotator cuff repair; pain intensity; pain quantitative plexus brachialis block; postoperative pain; visual analog scale