title: Joint range of motion after total shoulder arthroplasty with and without a continuous interscalene nerve block: a retrospective, case-control study.
abstract: OBJECTIVE
  Although a continuous interscalene nerve block (CISB) has been shown to provide potent analgesia after major shoulder surgery, its potential effects on postoperative rehabilitation remain uninvestigated. Therefore, this retrospective case-control study was undertaken to determine the association between CISB and joint range-of-motion after total shoulder arthroplasty (TSA).
  
  
  METHODS
  The medical records for patients who underwent TSA at our institution in the previous 3 years were examined. Each patient with a CISB (cases) was matched with a patient without a CISB (controls) for the following variables: age, gender, and TSA type (primary v revision). Data collected included maximum shoulder elevation and external rotation (primary endpoints), along with pre- and postoperative pain scores.
  
  
  RESULTS
  Of 134 charts reviewed, 25 cases were matched with an equal number of controls. On postoperative day 1, patients with or without a CISB achieved a median (5th-95th percentiles) of 85% (51-100) and 33% (11-56) of their surgeon-defined goal for elevation (P = .048), respectively, and attained 100% (33-100) and 17% (-81-68) for external rotation (P < .001), respectively. The median numeric rating pain score (NRS) during shoulder movement for patients with CISB was 2.0 (0.0-8.7) versus 8.5 (1.8-10.0) for patients without CISB (P < .001). Least, median, and highest resting NRS for the 24 hours after surgery were 0.0 (0.0-5.8), 1.0 (0.0-6.4), and 3.0 (0.0-9.0) for patients with CISB, respectively, versus 2.0 (0.0-7.7), 6.0 (0.3-9.6), and 8.0 (0.0-10.0) for patients without CISB (P = .030, P < .001, and P < .001 between groups, respectively).
  
  
  CONCLUSIONS
  The day after TSA, a CISB is associated with increased shoulder range of motion, most likely resulting from the potent analgesia these nerve blocks provide.
authors.affiliation: Department of Anesthesiology, University of Florida College of Medicine, PO Box 100254, 1600 SW Archer Road, Gainesville, FL 32610-0254, USA. bilfeld@ufl.edu
authors.forename: Brian M
authors.initials: BM
authors.lastname: Ilfeld
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Wright
authors.forename: F Kayser
authors.initials: FK
authors.lastname: Enneking
authors.forename: Timothy E
authors.initials: TE
authors.lastname: Morey
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement / Q000379:methods* / Q000534:rehabilitation; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009407:Nerve Block / Q000379:methods*; D010147:Pain Measurement / Q000379:methods; D010149:Postoperative Pain / Q000517:prevention & control*; D016059:Range of Motion, Articular / Q000187:drug effects* / Q000502:physiology; D020127:Recovery of Function / Q000187:drug effects; D012189:Retrospective Studies; D012785:Shoulder Joint / Q000502:physiology / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome