Skip to main content

Table 1 Selected characteristics of the participants who underwent primary unilateral total knee arthroplasty surgery n = 141

From: Prediction of poor outcomes six months following total knee arthroplasty in patients awaiting surgery

Variables considered for PR development n (%) Mean (SD) Other collected variables n (%) Mean (SD)
Demographics    Pre-surgery wait   
  Age (years)   66 (9.5) Time between enrolment on wait list and surgery (days)*   184 (120.8)
  Female 93 (66)   Categories of wait time   
  Marital status    ≤3 months 30 (21) 62.5 (16.9)
   Single, separated, divorced or widowed 51 (36)   >3-6 months 53 (38) 130.2 (28.7)
   Married or common law 90 (64)   >6-9 months 31 (22) 216.8 (25.1)
  Living alone 34 (24)   >9 months 27 (19) 386.3 (56.7)
Socioeconomic characteristics    Surgery postponed for personal reasons 9 (6)  
  Educational level (part or complete)    Surgical characteristics   
   High school or less 79 (56)   Implant type   
   College or University 62 (44)   Postero-stabilized 115 (82)  
  Employment status    Cruciate retaining 26 (18)  
   Unemployed or retired 108 (77)   Implant fixation   
   Employed 33 (23)   Cementless 4 (3)  
  Household income**    Hybrid 2 (1)  
   < $30 000 / year 48 (34)   Cemented 135 (96)  
   $30 000 - $59 999 / year 43 (31)   Implant bearing type   
   ≥ $60 000 / year 34 (24)   Mobile 4 (3)  
  Missing data 16 (11)   Fixed 137 (97)  
Psychosocial characteristics    Patella resurfacing 132 (93)  
  Psychological distress (/42)   7.2 (7.0) In-hospital complications   
  Social support°    0 109 (77)  
   Low 67 (48)   1 23 (16)  
   High 74 (52)   ≥2 10 (7)  
Clinical characteristics    Health services utilization   
  Diagnosis    Hospital length of stay (days)   7.5 (3.0)
   Osteoarthritis 136 (96)   Discharged directly home 123 (87)  
   Rheumatoid arthritis 5 (4)   Post-surgery community physiotherapy (hours)   14.7 (18.7)
  BMI¬ (kg/m2)   31.2 (6.2)    
  Comorbidities (/56)   6.5 (2.2)    
  Duration of knee symptoms before enrolment (years)   7.9 (8.1)    
  Contralateral knee pain§ 101 (72)     
  Use of a walking aid      
   At enrolment on wait list 55 (39)     
  1. SD: standard deviation.
  2. *Median (range): 148 days (32–692).
  3. **n = 125 – CND $.
  4. °Social support was dichotomized around the median score: Low (≤80) and High (>80).
  5. ¬Body mass index.
  6. n = 138.
  7. §WOMAC pain score at enrolment on pre-surgery wait list dichotomized into presence or absence of contralateral knee pain.
  8. In-hospital complications including: wound infection, dislocation, knee ankylosis and manipulation, cardiovascular/pulmonary/circulatory complications, peripheral/central nervous system involvement, urinary infection, acute confusion, tendon and ligament rupture or blood transfusion.