title: Osteoarthritis treatment using autologous conditioned serum after placebo.
abstract: OBJECTIVE
  Autologous conditioned serum (ACS) is a disease-modifying drug for treatment of knee osteoarthritis, and modest superiority over placebo was reported in an earlier randomized controlled trial (RCT). We hypothesized that when given the opportunity, placebo-treated patients from that RCT would now opt for ACS treatment, which would result in a greater clinical improvement than placebo.
  
  
  METHODS
  Of 74 patients treated with placebo in the previous trial, 20 opted for ACS treatment. Patients who did not choose further treatment were interviewed about their reasons. Clinical improvement of the 20 ACS-treated patients was measured using knee-specific clinical scores, as was "response shift" at 3 and 12 months.
  
  
  RESULTS
  In the 20 patients who did opt for ACS, the visual analog scale (VAS) score for pain improved; but after 12 months, clinical results were similar to those after placebo treatment. Response shift measurement demonstrated that the 20 patients had adapted to their disabilities during treatment.
  
  
  CONCLUSIONS
  Placebo-treated patients from an earlier trial were reluctant to undergo ACS treatment, in part due to the laborious nature of the therapy. In a subset of patients who opted for treatment, ACS treatment after placebo did not result in greater clinical improvement than placebo treatment only. However, due to the limited power of the current study and possible selection bias, definite advice on using or refraining from ACS cannot be given.
authors.affiliation: University Medical Center Utrecht , Department of Orthopaedics , Utrecht.
authors.forename: Marijn
authors.initials: M
authors.lastname: Rutgers
authors.forename: Laura B
authors.initials: LB
authors.lastname: Creemers
authors.forename: Kiem Gie
authors.initials: KG
authors.lastname: Auw Yang
authors.forename: Natasja J H
authors.initials: NJ
authors.lastname: Raijmakers
authors.forename: Wouter J A
authors.initials: WJ
authors.lastname: Dhert
authors.forename: Daniel B F
authors.initials: DB
authors.lastname: Saris
mesh_terms: D000328:Adult; D000368:Aged; D002755:Choice Behavior; D005260:Female; D005898:Glass; D006801:Humans; D007270:Injections, Intra-Articular; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000628:therapy*; D010147:Pain Measurement; D015990:Placebo Effect; D044967:Serum; D014182:Transplantation, Autologous; D016896:Treatment Outcome