Table 1

Clinical and demographic characteristics of patients with primary total hip or knee arthroplasty (THA/TKA)
Characteristic Primary THA Primary TKA
2 years 5 years 2 years 5 years
(n = 3,823) (n = 2,374) (n = 4,701) (n = 2,935)
Mean age ± SD 64.8 ± 13.2 64.3 ± 12.8 68.4 ± 9.5 68.5 ± 9.1
Men/women (%) 48%/52% 48%/52% 44%/56% 45%/55%
Age groups, n (%):
 ≤60 years 31% 31% 18% 17%
 >60 to 70 years 31% 33% 36% 39%
 >70 to 80 years 29% 28% 38% 38%
 >80 years 8% 6% 7% 6%
Body mass index, kg/m2
 ≤25 (normal) 25% 24% 13% 13%
 >25 to 29.9 (overweight) 39% 40% 35% 36%
 30 to 34.9 (mildly obese) 23% 23% 30% 30%
 35 to 39.9 (obese) 8% 8% 14% 14%
 ≥40 (morbidly obese) 4% 4% 8% 7%
ASA score:
 Class I to II 63% 65% 59% 60%
 Class III to IV 36% 35% 41% 40%
Implant fixation:
Cemented 10% 12% 98% 100%
Hybrid 55% 60% 0% 0%
Uncemented 35% 28% 0% 0%
Underlying diagnosis
 Inflammatory arthritis 2% 3% 3% 4%
 Osteoarthritis 88% 86% 96% 93%
 Avascular necrosis of bone 7% 7% - -
 Othera 3% 4% 2% 3%

All numbers were rounded to the nearest digit, therefore totals may not exactly add up to 100%.

Othera category includes the following: for primary THA: hip dysplasia, Legg-Perthe’s disease, slipped capital femoral epiphyses, failed previous osteotomy, failed previous arthrodeses, failed previous internal fixation, congenital dislocation of hip, pigmented villonodular synovitis, hemochromatosis, synovial chondromatosis, and so on; for primary TKA: genu varum, genu valgum, hemophilia, Paget’s disease, failed previous disease including arthrodesis, failed previous osteotomy, failed previous patellectomy, Chacot arthropathy, chondromalacia, pigmented villonodular synovitis, and so on.

ASA, American Society of Anesthesiologists.

Singh and Lewallen

Singh and Lewallen BMC Medicine 2013 11:144   doi:10.1186/1741-7015-11-144

Open Data