Table 1.
Demographic data of patients in the spacer-complication group (group A) and the no-spacer-complication group (group B)
| Characteristics | Overall (n = 31) | Group A (n = 14) | Group B (n = 17) | p-value | |||
|---|---|---|---|---|---|---|---|
| Age, median (IQR), y | 56 | (50 to 71) | 55 | (41 to 59) | 64 | (52 to 77) | 0.021 |
| Male, n (%) | 19 | (61.3) | 10 | (71.4) | 9 | (52.9) | 0.290 |
| BMI, median (IQR), kg/m2 | 23.7 | (22.1 to 27.7) | 23.5 | (21.9 to 29.4) | 23.8 | (22.6 to 25.7) | 0.787 |
| ASA class, n (%) | 0.436 | ||||||
| 2 | 11 | (35.5) | 6 | (42.9) | 5 | (29.4) | |
| 3 | 20 | (64.5) | 8 | (57.1) | 12 | (70.6) | |
| Prosthesis type, n (%) | 0.895 | ||||||
| Bipolar | 8 | (25.8) | 3 | (21.4) | 5 | (29.4) | |
| Primary | 11 | (35.5) | 4 | (28.6) | 7 | (41.2) | |
| Revision | 12 | (38.7) | 7 | (50.0) | 5 | (29.4) | |
| Comorbidities, n (%) | |||||||
| Diabetes mellitus | 9 | (29.0) | 4 | (28.6) | 5 | (29.4) | 0.959 |
| Renal disease | 3 | (9.7) | 2 | (14.3) | 1 | (5.9) | 0.431 |
| Liver disease | 6 | (19.4) | 2 | (14.3) | 4 | (23.5) | 0.517 |
| Drug abuse | 3 | (9.7) | 2 | (14.3) | 1 | (5.9) | 0.431 |
| Alcoholism | 3 | (9.7) | 2 | (14.3) | 1 | (5.9) | 0.835 |
| Psychiatric disorder | 2 | (6.5) | 2 | (14.3) | 0 | (0) | 0.107 |
| Classification of PJI, n (%) | 0.003 | ||||||
| Acute | 10 | (32.3) | 1 | (7.1) | 9 | (52.9) | |
| Chronic | 21 | (67.7) | 13 | (92.9) | 8 | (47.1) | |
| 1st stage | |||||||
| Pre-op ESR, median (IQR), mm/hr | 63 | (30 to 91) | 62 | (28 to 96) | 63 | (30 to 76) | 0.889 |
| Pre-op CRP, median (IQR), mg/dL | 15 | (6.3 to 73.0) | 29 | (9.2–95) | 14.8 | (5.9 to 55.7) | 0.578 |
| Approach, n (%) | 0.031 | ||||||
| Posterior | 23 | (74.2) | 13 | (92.9) | 10 | (58.8) | |
| Direct lateral | 8 | (25.8) | 1 | (7.1) | 7 | (41.2) | |
| Paprosky bone defect classification, n (%) | |||||||
| Acetabulum | 0.143 | ||||||
| I | 14 | (45.2) | 5 | (35.7) | 9 | (52.9) | |
| II (A + B + C) | 8 | (25.8) | 6 | (42.9) | 2 | (11.8) | |
| III (A + B) | 9 | (29.0) | 3 | (21.4) | 6 | (5.3) | |
| Femur | 0.977 | ||||||
| I | 8 | (25.8) | 4 | (28.6) | 4 | (23.5) | |
| II | 10 | (32.3) | 4 | (28.6) | 6 | (35.3) | |
| III (A + B) | 11 | (35.5) | 5 | (35.7) | 6 | (35.3) | |
| IV | 2 | (6.4) | 1 | (7.1) | 1 | (5.9) | |
| Additional spacer exchange | 13 | (41.9) | 6 | (42.9) | 7 | (41.2) | 0.953 |
| Recurrent infection | 10 | 3 | 7 | ||||
| Interim perioda, median (IQR), weeks | 14.5 | (11 to 32) | 15 | (10 to 20) | 13.5 | (11 to 27) | 0.950 |
| Reimplantationa | |||||||
| Pre-op ESR, median (IQR), mm/hr | 29.9 | (11.5 to 47.0) | 31.2 | (14.5 to 46.0) | 28.8 | (8.3 to 55.5) | 0.397 |
| Pre-op CRP, median (IQR), mg/dL | 16.7 | (1.32 to 5.5) | 28.7 | (1.83 to 6.1) | 6.9 | (1.0 to 5.7) | 0.156 |
| Follow-up perioda, median (IQR), months | 29 | (23 to 35.5) | 29 | (25 to 34) | 30 | (23 to 36) | 0.948 |
aOne patient in group A and one patient in group B had permanent spacer implantation without revision surgery and were excluded from calculation of the interim period, CRP/ESR before reimplantation, and duration of follow-up period
IQR interquartile range, BMI body mass index, ASA American Society of Anesthesiologists, ESR erythrocyte sedimentation rate, CRP C-reactive protein, PJI periprosthetic joint infection