title: Multicenter randomized controlled trial comparing early versus late aquatic therapy after total hip or knee arthroplasty.
abstract: OBJECTIVE
  To evaluate if the timing of aquatic therapy influences clinical outcomes after total knee arthroplasty (TKA) or total hip arthroplasty (THA).
  
  
  METHODS
  Multicenter randomized controlled trial with 3-, 6-, 12-, and 24-month follow-up.
  
  
  METHODS
  Two university hospitals, 1 municipal hospital, and 1 rural hospital.
  
  
  METHODS
  Patients (N=465) undergoing primary THA (n=280) or TKA (n=185): 156 men, 309 women.
  
  
  METHODS
  Patients were randomly assigned to receive aquatic therapy (pool exercises aimed at training of proprioception, coordination, and strengthening) after 6 versus 14 days after THA or TKA.
  
  
  METHODS
  Primary outcome was self-reported physical function as measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at 3-, 6-, 12-, and 24-months postoperatively. Results were compared with published thresholds for minimal clinically important improvements. Secondary outcomes included the Medical Outcomes Study 36-Item Short-Form Health Survey, Lequesne-Hip/Knee-Score, WOMAC-pain and stiffness scores, and patient satisfaction.
  
  
  RESULTS
  Baseline characteristics of the 2 groups were similar. Analyzing the total study population did not result in statistically significant differences at all follow-ups. However, when performing subanalysis for THA and TKA, opposite effects of early aquatic therapy were seen between TKA and THA. After TKA all WOMAC subscales were superior in the early aquatic therapy group, with effect sizes of WOMAC physical function ranging from .22 to .39. After THA, however, all outcomes were superior in the late aquatic therapy group, with WOMAC effect sizes ranging from .01 to .19. However, the differences between treatment groups of these subanalyses were not statistically significant.
  
  
  CONCLUSIONS
  Early start of aquatic therapy had contrary effects after TKA when compared with THA and it influenced clinical outcomes after TKA. Although the treatment differences did not achieve statistically significance, the effect size for early aquatic therapy after TKA had the same magnitude as the effect size of nonsteroidal anti-inflammatory drugs in the treatment of osteoarthritis of the knee. However, the results of this study do not support the use of early aquatic therapy after THA. The timing of physiotherapeutic interventions has to be clearly defined when conducting studies to evaluate the effect of physiotherapeutic interventions after TKA and THA.
authors.affiliation: Department of Orthopaedic Surgery, University of Schleswig-Holstein Medical Center, Kiel Campus, Kiel, Germany. liebs@liebs.eu
authors.forename: Thoralf R
authors.initials: TR
authors.lastname: Liebs
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Herzberg
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Rüther
authors.forename: Jörg
authors.initials: J
authors.lastname: Haasters
authors.forename: Martin
authors.initials: M
authors.lastname: Russlies
authors.forename: Joachim
authors.initials: J
authors.lastname: Hassenpflug
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000534:rehabilitation*; D019645:Arthroplasty, Replacement, Knee / Q000534:rehabilitation*; D005081:Exercise Therapy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006875:Hydrotherapy; D008297:Male; D015207:Osteoarthritis, Hip / Q000601:surgery; D020370:Osteoarthritis, Knee / Q000601:surgery; D010147:Pain Measurement; D017060:Patient Satisfaction; D026741:Physical Therapy Modalities; D013997:Time Factors