Page 34 - The value of total hip and knee arthroplasties for patients

Chapter 2
Included versus not-included patients
Regarding the comparison patients who were eligible and who did and who did not return a preoperative questionnaire, no differences were found in the sex distribution. In addition, the included patients were somewhat younger as compared to patients not returning the preoperative questionnaire (table 3).
Table 3. Preoperative characteristics of included and not-included patients undergoing Total Hip or Knee Arthroplasty (THA orTKA)
Included patients N=1035 and 970 Sex, Female; n (%)
Age, years; mean (SD)
BMI; mean (SD)
Employed, yes; n (%)
HOOS or KOOS; mean (SD) Activity Daily Living
Pain
Quality of Life
Sport and Recreation Symptoms
Oxford Knee/Hip Score; mean (SD) EuroQol (EQ)5D score ; mean (SD) EuroQol (EQ)5D VAS scale; mean (SD)
Short Form (SF)-12; mean (SD) Mental Component Score Physical Component Score
Not included patients N=761 and 666† Sex, Female; n (%)
Age, years; mean (SD)
THA
643 (62%) 68 (10.0) 28 (9.6) 248 (24%)
46 (23.5) 38 (18.9) 33 (10.5) 18 (18.9) 40 (18.9)
24 (8.4) 0.60 (0.26) 66 (18.5)
55 (9.8) 32 (9.4)
494 (65%)‡ 70 (10.2) §
TKA
642 (66%) 67 (9.0) 29 (4.5) 214 (23%)
44 (18.5) 38 (18.2) 34 (10.8) 11 (14.2) 43 (13.2)
24 (7.7) 0.64 (0.24) 68 (18.0)
55 (9.7) 32 (9.1)
474 (71%)‡ 69 (10.1) §
BMI = Body Mass Index
HOOS = Hip disability and Osteoarthritis Outcome Score
KOOS = Knee Injury and Osteoarthritis Outcome Score
†Eligible patients invited to participate not returning the preoperative questionnaire
‡ No statistically significant differences between patients included preoperatively or 6 months postoperatively (Chi-Square test)
§ Statistically significant different between patients included preoperatively or 6 months postoperatively (p-value=0.001 for THA as well as TKA, unpaired t-test)
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