Table 2. Comparison of Baseline Characteristics of Nonevaluable and Evaluable Patients for the Primary End Point at Month 1.
| Characteristic | Patients, No. (%) | P value | ||
|---|---|---|---|---|
| Nonevaluable (n = 16) | Evaluable (n = 117) | Total (N = 133) | ||
| Randomization arm | ||||
| pSAE | 9 (56.3) | 57 (48.7) | 66 (49.6) | .61 |
| SURV | 7 (43.8) | 60 (51.3) | 67 (50.4) | |
| Sex | ||||
| Female | 1 (6.3) | 27 (23.1) | 28 (21.1) | .19 |
| Male | 15 (93.8) | 90 (76.9) | 105 (78.9) | |
| Age, median (IQR), y | 27 (22-35) | 31 (23-48) | 30 (23-47) | .56 |
| Distance between hospital and residence, median (IQR), km | 104 (35-950) | 30 (15-92) | 30 (15-100) | .002 |
| Time from unintentional injury to enrollment in trial, median (IQR), h | ||||
| 0-23 | 11 (68.8) | 60 (51.3) | 71 (53.4) | .22 |
| 24-48 | 5 (31.3) | 57 (48.7) | 62 (46.6) | |
| Circumstances of unintentional injury | ||||
| Traffic | 5 (31.3) | 73 (62.4) | 78 (58.6) | .04 |
| Domestic | 2 (12.5) | 6 (5.1) | 8 (6.0) | |
| Sport | 8 (50.0) | 24 (20.5) | 32 (24.1) | |
| Work | 1 (6.3) | 10 (8.5) | 11 (8.3) | |
| Other | 0 | 4 (3.4) | 4 (3.0) | |
| OIS grade (after expert rereading of CT scan images)a | ||||
| 3 | 12 (75.0) | 68 (58.1) | 80 (60.2) | .51 |
| 4 | 4 (25.0) | 46 (39.3) | 50 (37.6) | |
| 5 | 0 | 3 (2.6) | 3 (2.3) | |
| NISS, median (IQR)b | 19.5 (10-31.5) | 19 (13-26) | 19 (13-27) | .71 |
| WOMAC score available before unintentional injuryc | 12 (75.0) | 104 (88.9) | 116 (87.2) | .13 |
| Missing | 4 (25.0) | 13 (11.1) | 17 (12.8) | |
| WOMAC score = 0 before unintentional injury, No./total No. (%)c | 10/12 (83.3) | 82/104 (78.8) | 92/116 (79.3) | >.99 |
Abbreviations: CT, computed tomography; IQR, interquartile range; NISS, New Injury Severity Score; OIS, Organ Injury Scale; pSAE, prophylactic splenic arterial embolization; SURV, surveillance, with embolization only if necessary; WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index.
The OIS from the American Association for the Surgery of Trauma22 is a widely used scanographic score. It takes into account the type of damage (eg, hematoma or tearing), the localization in the splenic gland (eg, intraparenchymal or subcapsular), and the percentage of devascularized tissue. Grade 3 includes subcapsular hematoma of more than 50% of the spleen surface, rupture, spreading, or bleeding and/or intraparenchymal hematoma evolutive or diameter greater than 5 cm and/or capsular tear with a depth greater than 3 cm or that involves trabecular vessels. Grade 4 includes ruptured hematoma, lesion reaching segmental or hilar vessels, or more than 25% devascularized spleen. Grade 5 corresponds to complete splenic fragmentation.
The NISS29 is a widely used anatomical score giving an overall score for the anatomical lesions of a person with multiple traumas. Each organ involved is scored according to the OIS from 1 (mild) to 5 (total destruction or devascularization of the organ) according to the criteria of the American Association for the Surgery of Trauma. The NISS is calculated from the OIS of the 3 most serious lesions as follows: NISS = a2 + b2 + c2 (eg, a patient with a cerebral contusion rated AIS = 3, a spleen fracture rated AIS = 4, and minor hepatic injury rated AIS = 2 will have an NISS of 9 + 16 + 4 = 29). A trauma is considered severe when the NISS is 15 or more.30
The WOMAC33 self-administered questionnaire uses a Likert scale with 5 possible answers (none = 0, minimum = 1, moderate = 2, severe = 3, and extreme = 4) to several questions about physical functional impairment, pain, and stiffness. The minimum score (0) corresponds to no affliction and the maximum score (96) corresponds to severe distress and disability.