title: [Quality of Outcome after Primary Total Hip Replacement at a Maximum Care Hospital in Relation to Preoperative Influencing Factors].
abstract: BACKGROUND
  As the need for joint replacements will continue to rise, the outcome of primary total hip replacement (THR) must be improved and stabilised at a high level. In this study, we investigated whether pre-operative risk factors, such as gender, age and body weight at the time of the surgery or a restricted physical status (ASA-Status > 2 or Kellgren and Lawrence grade > 2) have a negative influence on the post-operative results or on patient satisfaction.
  
  
  METHODS
  Retrospective data collection and a prospective interview were performed with 486 patients who underwent primary total hip replacement between January 2007 and December 2010 in our hospital. The patients' satisfaction and quality of life were surveyed with the WOMAC-Score, SF-36 and EuroQol-5. Differences between more than two independent spot tests were tested with the non-parametric Kruskal-Wallis test. Differences between two independent spot tests were tested with the non-parametric Mann-Whitney U test. The frequencies were reported and odds ratios calculated. The confidence interval was set at 95 %. The level of significance was p < 0.05.
  
  
  RESULTS
  The average WOMAC-Score was 77.1 and the total score of the SF-36 was 66.9 points. The patients declared an average EuroQol Index of 0.81. Our data show that the patients' gender did not influence the duration of surgery or the scores. However, female patients tended to exhibit more postoperative complications. However, increased patient age at the time of surgery was associated with an increased OR for duration of surgery, length of stay and risk of complications. Patients who had a normal body weight at time of the surgery showed better peri- and post-operative results. We showed that the preoperative estimated Kellgren and Lawrence grade had a significant influence on the duration of surgery. The ASA classification influenced the duration of surgery as well the length of stay and the rate of complications.
  
  
  CONCLUSIONS
  The quality of results after primary THR depends on preoperative factors. Existing comorbidities have a significant influence on the duration of surgery and therefore on the perioperative rate of complications and the postoperative outcome. Despite improvements in the functional and subjective outcome after primary THR, an adverse preoperative symptomatic status is associated with less favourable postoperative results.
authors.affiliation: Orthopädische Klinik und Poliklinik, Universitätsmedizin Rostock.
authors.forename: K
authors.initials: K
authors.lastname: Osmanski-Zenk
authors.affiliation: Orthopädische Klinik und Poliklinik, Universitätsmedizin Rostock.
authors.forename: N S
authors.initials: NS
authors.lastname: Steinig
authors.affiliation: Institut für Biostatistik und Informatik in Medizin und Alternsforschung, Universitätsmedizin Rostock.
authors.forename: Ä
authors.initials: Ä
authors.lastname: Glass
authors.affiliation: Orthopädische Klinik und Poliklinik, Universitätsmedizin Rostock.
authors.forename: W
authors.initials: W
authors.lastname: Mittelmeier
authors.affiliation: Orthopädische Klinik und Poliklinik, Forschungslabor für Biomechanik und Implantattechnologie, Universitätsmedizin Rostock.
authors.forename: R
authors.initials: R
authors.lastname: Bader
mesh_terms: D017677:Age Distribution; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000592:standards / Q000706:statistics & numerical data*; D001835:Body Weight; D015897:Comorbidity; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D009765:Obesity / Q000453:epidemiology; D061646:Operative Time; D010003:Osteoarthritis / Q000453:epidemiology* / Q000628:therapy*; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data; D017060:Patient Satisfaction / Q000706:statistics & numerical data*; D011300:Preoperative Care / Q000592:standards / Q000706:statistics & numerical data*; D015995:Prevalence; D011785:Quality Assurance, Health Care; D011787:Quality of Health Care / Q000706:statistics & numerical data* / Q000639:trends; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D062606:Tertiary Care Centers; D016896:Treatment Outcome