Table III.
Postoperative outcomes following primary joint arthroplasty.
| BMI < 40 kg/m2 | Morbidly obese | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Joint | Total | PLOS, n (%) | OOH, n (%) | ED, n (%) | Gen re-ad, n (%) | WI re-ad, n (%) | Total | PLOS, n (%) | OOH, n (%) | ED, n (%) | Gen re-ad, n (%) | WI re-ad, n (%) |
| THA | 2,236 | 562 (25.1) | 282 (12.6) | 357 (16.0) | 175 (7.8) | 7 (0.3) | 134 | 38 (28.4) | 17 (12.7) | 23 (17.2) | 8 (6.0) | 2 (1.5) |
| TKA | 1,868 | 643 (34.4) | 251 (13.4) | 296 (15.8) | 122 (6.5) | 5 (0.3) | 241 | 92* (38.2) | 32† (13.3) | 40‡ (16.6) | 17§ (7.0) | 2 (0.8) |
| UKA | 215 | 25 (11.6) | 17 (7.9) | 24 (11.2) | 10 (4.6) | 0 (0.0) | 17 | 1 (5.9) | 2 (11.8) | 2 (11.8) | 1 (5.9) | 0 (0.0) |
| Total | 4,319 | 1,230 (28.5) | 550 (12.7) | 677 (15.7) | 307 (7.1) | 12 (0.3) | 392 | 131¶ (33.4) | 51 (13.0) | 65 (16.6) | 26 (6.6) | 4** (1.0) |
Data presented as a percentage of the total number of joints within each BMI category.
Of the patients who had a prolonged length of stay (LOS), a significantly greater proportion were total knee arthroplasty (TKA) patients with a BMI ≥ 40 kg/m2 (70.2%; 92/131) compared to those TKA patients with a BMI < 40 kg/m2 (52.3%; 643/1,230): Odds ratio 2.2 (95% confidence interval (CI) 1.5 to 3.2); p < 0.001, Fisher’s exact test.
Of the patients who attended out of hour attendance, a significantly greater proportion were TKA patients with a BMI ≥ 40 kg/m2 (63.7%; 32/51) compared to TKA patients with a BMI < 40 kg/m2 (45.6%; 251/550): Odds ratio 2.0 (95% CI 1.1 to 3.6); p = 0.019, Fisher’s exact test.
Of the patients who attended the emergency department, a significantly greater proportion were TKA patients with a BMI ≥ 40 kg/m2 (61.5%; 40/65) compared to TKA patients with a BMI < 40 kg/m2 (43.7%; 296/677): Odds ratio 2.1 (95% CI 1.2 to 3.5); p = 0.006, Fisher’s exact test.
Of the patients who had a general readmission, a significantly greater proportion were TKA patients with a BMI ≥ 40 kg/m2 (65.4%; 17/26) compared to BMI < 40 kg/m2 TKA patients (38.5%; 122/307): Odds ratio 2.9 (95% CI 1.2 to 6.6); p = 0.011, Fisher’s exact test.
Overall, a significantly greater proportion of patients with a BMI ≥ 40 kg/m2 (131/392; 33.4%) had a prolonged LOS compared to patients with a BMI < 40 kg/m2 (1,230/4,319; 28.5%); Odds ratio 1.3 (95% CI 1.0 to 1.6); p = 0.045, Fisher’s exact test.
A significantly greater proportion of BMI ≥ 40 kg/m2 patients (1.0%, 4/392) were readmitted due to a wound infection within 12 months of their index surgery compared to BMI < 40 kg/m2 patients (0.3% 12/4,319); Odds ratio 3.70 (95% CI 1.2 to 11.5); p = 0.049, Fisher’s exact test.
ED, emergency department attendance within 90 days; OOH, out of hour attendance within 90 days; PLOS, prolonged length of stay; WI Re-ad, wound infection readmission within 12 months.; Gen Re-ad, general readmission within 90 days