title: Prognostic factors in carpal tunnel syndrome treated with a corticosteroid injection.
abstract: BACKGROUND
  Symptoms often return in patients with carpal tunnel syndrome (CTS) who are treated with a local corticosteroid injection. We aimed to determine prognostic factors for a successful long-term outcome.
  
  
  METHODS
  We prospectively followed 113 patients who received an injection for CTS. Clinical, electrophysiological, and ultrasonographic tests were done at baseline, and clinical outcome was evaluated after 1, 3, 6, and 12 months. The primary outcome measure for success was no need for additional treatment (e.g., surgery) within 1 year.
  
  
  RESULTS
  After 1 month, most patients improved, but after 12 months 67.4% had surgery. Patients with a successful outcome had a lower median nerve ultrasonographic cross-sectional area (CSA) at the pisiform bone, a lower swelling ratio, and a lower symptom severity score.
  
  
  CONCLUSIONS
  Less pronounced median nerve swelling measured by ultrasonography may indicate a less severe stage of CTS, which is more likely to respond to treatment with a corticosteroid injection.
authors.affiliation: Department of Neurology, Atrium Medical Centre, P.O. Box 4446, Heerlen 6401 CX, The Netherlands. verameys@hotmail.com
authors.forename: Vera
authors.initials: V
authors.lastname: Meys
authors.forename: Sam
authors.initials: S
authors.lastname: Thissen
authors.forename: Stan
authors.initials: S
authors.lastname: Rozeman
authors.forename: Roy
authors.initials: R
authors.lastname: Beekman
mesh_terms: D000305:Adrenal Cortex Hormones / Q000008:administration & dosage*; D002349:Carpal Tunnel Syndrome / Q000175:diagnosis* / Q000188:drug therapy* / Q000503:physiopathology; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007270:Injections, Intra-Articular; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D000305:Adrenal Cortex Hormones