Table 2.
Operative treatments, complications and events by center
| (SPS+DS) | A (n=126) |
B (n=87) |
C (n=91) |
D (n=69) |
E (n=32) |
F (n=76) |
G (n=81) |
H (n=78) |
I (n=30) |
J (n=47) |
K (n=72) |
p-value |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Procedure, no. (%) | <0.001 | |||||||||||
| Decompression only | 80 (65%) | 31 (37%) | 52 (57%) | 39 (57%) | 12 (40%) | 40 (53%) | 22 (27%) | 35 (46%) | 11 (38%) | 23 (49%) | 31 (43%) | |
| Non-instrumented fusion | 11 (9%) | 10 (12%) | 36 (40%) | 5 (7%) | 4 (13%) | 17 (23%) | 4 (5%) | 8 (11%) | 4 (14%) | 3 (6%) | 1 (1%) | |
| Instrumented fusion | 33 (27%) | 43 (51%) | 3 (3%) | 24 (35%) | 14 (47%) | 18 (24%) | 55 (68%) | 33 (43%) | 14 (48%) | 21 (45%) | 40 (56%) | |
| Multi-level fusion, no. (%) | 10 (8%) | 12 (14%) | 2 (2%) | 1 (1%) | 3 (9%) | 19 (25%) | 23 (28%) | 15 (19%) | 4 (13%) | 8 (17%) | 7 (10%) | <0.001 |
| Laminectomy Level, no (%) | ||||||||||||
| L2–L3 | 38 (30%) | 18 (21%) | 16 (18%) | 10 (15%) | 11 (35%) | 33 (44%) | 8 (11%) | 23 (29%) | 9 (31%) | 12 (26%) | 14 (20%) | <0.001 |
| L3–L4 | 83 (66%) | 39 (45%) | 46 (51%) | 37 (54%) | 20 (65%) | 61 (81%) | 25 (34%) | 56 (72%) | 18 (62%) | 40 (85%) | 38 (55%) | <0.001 |
| L4–L5 | 124 (99%) | 84 (97%) | 82 (90%) | 62 (91%) | 29 (94%) | 73 (97%) | 74 (97%) | 75 (96%) | 26 (90%) | 45 (96%) | 64 (90%) | 0.045 |
| L5-S1 | 28 (22%) | 49 (56%) | 19 (21%) | 12 (18%) | 6 (19%) | 54 (72%) | 24 (32%) | 40 (51%) | 7 (24%) | 12 (26%) | 12 (17%) | <0.001 |
| Levels decompresssed, no. (%) | <0.001 | |||||||||||
| 0 | 1 (1%) | 0 (0%) | 0 (0%) | 1 (1%) | 1 (3%) | 1 (1%) | 5 (6%) | 0 (0%) | 1 (3%) | 0 (0%) | 1 (1%) | |
| 1 | 35 (28%) | 27 (31%) | 45 (49%) | 29 (42%) | 10 (31%) | 10 (13%) | 36 (44%) | 13 (17%) | 11 (37%) | 3 (6%) | 30 (42%) | |
| 2 | 44 (35%) | 31 (36%) | 23 (25%) | 28 (41%) | 8 (25%) | 12 (16%) | 27 (33%) | 28 (36%) | 7 (23%) | 28 (60%) | 26 (36%) | |
| 3+ | 46 (37%) | 29 (33%) | 23 (25%) | 11 (16%) | 13 (41%) | 53 (70%) | 13 (16%) | 37 (47%) | 11 (37%) | 16 (34%) | 15 (21%) | |
| Operation time, minutes (SD) | 74 (41.4) | 180.8 (69.4) | 148.8 (63.4) | 186.8 (82.3) | 192.3 (73.3) | 172.9 (67.1) | 235.9 (106.1) | 175.9 (69.4) | 177.5 (79) | 196 (74.8) | 181.8 (68.1) | <0.001 |
| Blood loss, cc (SD) | 174.5 (144.1) | 686.5 (587.5) | 441.4 (425.8) | 322.1 (228.1) | 397.3 (293.9) | 686.4 (506.8) | 425.5 (355.1) | 405.1 (336.1) | 512.9 (398) | 821.3 (892.5) | 296.5 (223.5) | <0.001 |
| Blood Replacement, no. (%) | ||||||||||||
| Intraoperative replacement | 5 (4%) | 31 (36%) | 10 (11%) | 17 (25%) | 2 (7%) | 24 (32%) | 24 (30%) | 23 (29%) | 5 (17%) | 12 (26%) | 15 (21%) | <0.001 |
| Post-operative transfusion | 7 (6%) | 27 (31%) | 3 (3%) | 2 (3%) | 3 (10%) | 9 (12%) | 12 (15%) | 8 (10%) | 0 (0%) | 6 (13%) | 23 (32%) | <0.001 |
| Lenth of hospital stay, days (SD)** | 2.3 (1.3) | 3.7 (1.8) | 3.1 (3.5) | 4.5 (3.1) | 5.5 (3.8) | 5.1 (2.7) | 4.8 (3.5) | 3.4 (2) | 3.8 (1.4) | 5.3 (4.1) | 4.7 (2) | <0.001 |
| Intraoperative complications§ | ||||||||||||
| Dural tear/ spinal fluid leak | 6 (5%) | 11 (13%) | 11 (12%) | 5 (7%) | 0 (0%) | 13 (17%) | 3 (4%) | 14 (18%) | 3 (10%) | 8 (17%) | 4 (6%) | 0.003 |
| Vascular injury | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 1 (1%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0.56 |
| Other | 0 (0%) | 3 (3%) | 5 (5%) | 1 (1%) | 0 (0%) | 0 (0%) | 1 (1%) | 0 (0%) | 0 (0%) | 0 (0%) | 2 (3%) | 0.047 |
| None | 120 (95%) | 73 (84%) | 76 (84%) | 63 (91%) | 31 (100%) | 62 (83%) | 77 (95%) | 64 (82%) | 27 (90%) | 39 (83%) | 66 (92%) | 0.004 |
| Postoperative complications/events¶ | ||||||||||||
| Nerve root injury | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 1 (1%) | 0 (0%) | 0 (0%) | 0 (0%) | 0.53 |
| Wound dehiscence | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 1 (1%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0.56 |
| Wound hematoma | 1 (1%) | 0 (0%) | 0 (0%) | 1 (1%) | 0 (0%) | 0 (0%) | 2 (2%) | 0 (0%) | 0 (0%) | 0 (0%) | 1 (1%) | 0.57 |
| Wound Infection | 3 (2%) | 0 (0%) | 5 (5%) | 1 (1%) | 3 (10%) | 1 (1%) | 2 (2%) | 4 (5%) | 0 (0%) | 0 (0%) | 0 (0%) | 0.033 |
| Other | 18 (14%) | 8 (9%) | 2 (2%) | 0 (0%) | 5 (17%) | 2 (3%) | 4 (5%) | 9 (12%) | 1 (3%) | 5 (11%) | 6 (8%) | 0.002 |
| None | 98 (78%) | 55 (64%) | 81 (89%) | 64 (96%) | 21 (70%) | 63 (85%) | 60 (75%) | 61 (78%) | 28 (97%) | 36 (77%) | 45 (62%) | <0.001 |
| Post-operative mortality (death within 6 weeks of surgery) | 0 (0%) | 0 (0%) | 2 (2.2%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0.12 |
| Post-operative mortality (death within 3 months of surgery) | 0 (0%) | 0 (0%) | 2 (2.2%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 0 (0%) | 1 (1.4%) | 0.27 |
| Additional surgeries (1-year rate)‖ | 11 (9%) | 1 (1%) | 5 (5%) | 2 (3%) | 3 (9%) | 5 (6%) | 9 (11%) | 5 (6%) | 1 (3%) | 3 (6%) | 2 (3%) | 0.22 |
| Additional surgeries (2-year rate)‖ | 17 (13%) | 6 (7%) | 11 (12%) | 3 (4%) | 4 (12%) | 9 (11%) | 12 (15%) | 7 (9%) | 3 (10%) | 5 (11%) | 3 (4%) | 0.33 |
| Additional surgeries (3-year rate)‖ | 24 (19%) | 7 (8%) | 13 (14%) | 6 (8%) | 5 (15%) | 10 (12%) | 14 (17%) | 9 (11%) | 3 (10%) | 7 (15%) | 3 (4%) | 0.13 |
| Additional surgeries (4-year rate)‖ | 26 (21%) | 11 (13%) | 16 (17%) | 6 (8%) | 5 (15%) | 10 (12%) | 14 (17%) | 10 (13%) | 3 (10%) | 9 (19%) | 4 (5%) | 0.17 |
| Recurrent stenosis / progressive listhesis | 15 (12%) | 3 (4%) | 4 (4%) | 3 (4%) | 3 (9%) | 4 (5%) | 1 (1%) | 3 (4%) | 1 (3%) | 6 (13%) | 1 (1%) | |
| Pseudarthrosis / fusion exploration | 1 (0.8%) | 1 | 0 | 0 | 0 | 0 | 1 (1.3%) | 0 | 0 | 1 | 0 | |
| Complication or Other | 7 (5.6%) | 4 (4.7%) | 5 (5.5%) | 1 | 1 | 6 (7.7%) | 9 (11.4%) | 3 (4.1%) | 1 | 4 (8.5%) | 2 (2.8%) | |
| New condition | 4 (3.2%) | 2 (2.4%) | 6 (6.6%) | 0 | 0 | 1 | 3 (3.8%) | 1 | 0 | 0 | 0 |
§
None of the following were reported: aspiration, nerve root injury, operation at wrong level.
¶
Any reported complications up to 8 weeks post operation. None of the following were reported: bone graft complication, cerebrospinal fluid leak, paralysis, cauda equina injury, pseudarthrosis.
‖
One-, two-, three- and four-year post-surgical re-operation rates are Kaplan Meier estimates and p-values are based on the log-rank test. Numbers and percentages are based on the first additional surgery if more than one additional surgery. Surgeries include any additional spine surgery not just re-operation at the same level.
**
One of the HSS patients had a length of hospital stay of 372 days—not counting that case the average length of hospital stay for the HSS site would be 5.1 (2.7).