Table I.
Demographic and clinical characteristics of patients with and without positive cultures during shoulder arthroplasty
| Characteristic | Overall sample (N = 83) | Positive cultures (n = 37) | No positive cultures (n = 46) | P value |
|---|---|---|---|---|
| Demographics | ||||
| Age, yr, M (SD) | 64.20 (10.91) | 63.78 (12.84) | 64.54 (9.20) | .76 |
| Male sex, n (%) | 54 (65.06) | 27 (72.97) | 27 (58.70) | .25 |
| White, non-Hispanic, n (%) | 76 (91.57) | 33 (89.19) | 43 (93.48) | .67 |
| Patient factors | ||||
| Currently a smoker, n (%) | 11 (13.25) | 04 (10.81) | 07 (15.22) | .75 |
| BMI, M (SD) | 29.82 (5.06) | 30.07 (5.18) | 29.61 (5.01) | .69 |
| Total number of medical problems, M (SD) | 1.41 (1.25) | 1.48 (1.17) | 1.34 (1.32) | .62 |
| History of ipsilateral shoulder infection, n (%) | 05 (6.02) | 05 (13.51) | 0 (0.00) | .015∗ |
| Type of previous shoulder surgery, n (%) | .58 | |||
| Arthroscopic | 61 (79.22) | 25 (75.76) | 36 (81.82) | |
| Open | 16 (20.78) | 08 (24.24) | 08 (18.18) | |
| Number of ipsilateral shoulder surgeries, M (SD) | 1.43 (0.87) | 1.32 (0.53) | 1.52 (1.07) | .28 |
| Duration between surgeries, years, M (SD) | 9.69 (10.05) | 9.51 (9.48) | 9.85 (10.62) | .89 |
| Comorbidities, n (%) | ||||
| Type 2 diabetes | 22 (26.51) | 10 (27.03) | 12 (26.09) | >.99 |
| Rheumatoid arthritis | 05 (6.02) | 02 (5.41) | 03 (6.52) | >.99 |
| Thyroid disease | 14 (16.87) | 04 (10.81) | 10 (21.74) | .24 |
| Hepatitis C | 06 (7.23) | 03 (8.11) | 03(6.52) | >.99 |
| Heart disease | 17 (20.48) | 11 (29.73) | 06 (13.04) | .10 |
| Laboratory values, n (%) | ||||
| Elevated preoperative CRP | 11 (21.15) | 06 (25.00) | 05 (17.86) | .75 |
| Elevated preoperative ESR | 10 (23.26) | 05 (21.74) | 05 (25.00) | >.99 |
| Elevated preoperative WBC count | 02 (2.60) | 00 (0.00) | 02 (4.76) | .50 |
M, sample mean; SD, standard deviation; BMI, body mass index; CRP, C-reactive protein; ESR, erythrocyte sedimentation rate; WBC, white blood cell.
Positive culture was operationalized as the presence of at least 1 positive culture. The P value (2-tailed) is associated with the test of Group differences (positive cultures vs. no presence of positive cultures) on each characteristic; t test was used for continuous variables and Fisher exact test was used for categorical variables. Duration between surgeries = time (years) between first shoulder surgery and first shoulder arthroplasty.
∗
False discovery rate = 0.27.