title: Trajectories of musculoskeletal shoulder pain after spinal cord injury: Identification and predictors.
abstract: OBJECTIVE
  Although shoulder pain is a problem in up to 86% of persons with a spinal cord injury (SCI), so far, no studies have empirically identified longitudinal patterns (trajectories) of musculoskeletal shoulder pain after SCI. The objective of this study was: (1) to identify distinct trajectories of musculoskeletal shoulder pain in persons with SCI, and (2) to determine possible predictors of these trajectories.
  
  
  METHODS
  Multicenter, prospective cohort study in 225 newly injured persons with SCI.
  
  
  METHODS
  Shoulder pain was assessed on five occasions up to 5 years after discharge. Latent class growth mixture modeling was used to identify the distinct shoulder pain trajectories.
  
  
  RESULTS
  Three distinct shoulder pain trajectories were identified: (1) a "No or Low pain" trajectory (64%), (2) a "High pain" (30%) trajectory, and (3) a trajectory with a "Decrease of pain" (6%). Compared with the "No or Low pain" pain trajectory, the "High pain" trajectory consisted of more persons with tetraplegia, shoulder pain before injury, limited shoulder range of motion (ROM), lower manual muscle test scores, or more spasticity at t1. Multiple logistic regression analysis showed two significant predictors for the "High pain" trajectory (as compared with the "No or Low pain" trajectory): having a tetraplegia (odds ratio (OR) = 3.2; P = 0.002) and having limited shoulder ROM (OR = 2.8; P = 0.007).
  
  
  CONCLUSIONS
  Shoulder pain in people with SCI follows distinct trajectories. At risk for belonging to the "High pain" trajectory are persons with tetraplegia and those with a limited shoulder ROM at start of active rehabilitation.
authors.forename: Inge E
authors.initials: IE
authors.lastname: Eriks-Hoogland
authors.forename: Trynke
authors.initials: T
authors.lastname: Hoekstra
authors.forename: Sonja
authors.initials: S
authors.lastname: de Groot
authors.forename: Gerold
authors.initials: G
authors.lastname: Stucki
authors.forename: Marcel W
authors.initials: MW
authors.lastname: Post
authors.forename: Lucas H
authors.initials: LH
authors.lastname: van der Woude
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D015984:Causality; D015897:Comorbidity; D018450:Disease Progression; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D017063:Outcome Assessment, Health Care / Q000379:methods* / Q000706:statistics & numerical data; D010147:Pain Measurement / Q000379:methods* / Q000706:statistics & numerical data; D011379:Prognosis; D020127:Recovery of Function; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D017678:Sex Distribution; D020069:Shoulder Pain / Q000175:diagnosis* / Q000453:epidemiology / Q000534:rehabilitation*; D013119:Spinal Cord Injuries / Q000175:diagnosis* / Q000453:epidemiology / Q000534:rehabilitation*; D055815:Young Adult
keywords: Longitudinal studies; Prospective studies; Shoulder; Spinal cord injuries; Upper extremity