Table 3.
Surgical treatments, complications, and events. Values are numbers (percentages) of participants unless stated otherwise
| Variables | Aggregate cohort (n=885) | Difference (95% CI) | P value | Propensity matched cohort (n=492) | Difference (95% CI) | P value | |||
|---|---|---|---|---|---|---|---|---|---|
| Laminectomy group | Microdecompression group | Laminectomy group | Microdecompression group | ||||||
| No of levels decompressed: | |||||||||
| 1 | 191 (46.1) | 305 (64.8) | — | <0.001 | 135 (54.9) | 130 (52.8) | — | 0.678 | |
| 2 | 223 (53.9) | 166 (35.2) | — | 111 (45.1) | 116 (47.2) | — | |||
| Spine level of surgery: | |||||||||
| L2-L3 | 30 (7.2) | 20 (4.2) | — | 0.054 | 18 (7.3) | 13 (5.3) | — | 0.424 | |
| L3-L4 | 218 (52.7) | 218 (56.3) | — | 0.058 | 116 (47.2) | 126 (51.2) | — | 0.407 | |
| L4-L5 | 344 (83.1) | 371 (78.8) | — | 0.103 | 197 (80.1) | 203 (82.5) | — | 0.561 | |
| L5-S1 | 45 (10.9) | 28 (5.9) | — | 0.008 | 26 (10.6) | 20 (8.1) | — | 0.451 | |
| Operation time (mins): | |||||||||
| Single level decompression | 94.2 | 83.0 | 11.2 (4.9 to 17.5) | <0.001 | 94.2 | 87.3 | 6.9 (-3.6 to 17.4) | 0.149 | |
| Two level decompression | 109.2 | 114.3 | −5.1 (−14.0 to 3.7) | 0.375 | 103.8 | 118.0 | −14.2 (−27.6 to 7.6) | 0.259 | |
| No of days in hospital: | |||||||||
| Single level decompression | 3.4 | 1.9 | 1.5 (1.7 to 2.6) | <0.001 | 4.1 | 2.5 | 1.6 (1.4 to 3.1) | <0.001 | |
| Two level decompression | 3.1 | 2.3 | 0.8 (1.0 to 2.2) | 0.003 | 4.0 | 2.0 | 2.0 (−0.1 to 2.4) | 0.006 | |
| Patients with complications | 62 (15.0) | 46 (9.8) | — | 0.018 | 36 (14.6) | 26 (10.6) | — | 0.229 | |
| Perioperative complications: | 22 (3.2) | 15 (3.2) | — | 0.114 | 11 (4.5) | 7 (2.8) | — | 0.454 | |
| Dural tear or spinal fluid leak | 21 (5.1) | 11 (2.3) | — | 0.030 | 13 (5.3) | 6 (2.4) | — | 0.143 | |
| Nerve injury | 0 (0) | 0 (0) | — | — | 0 (0) | 0 (0) | — | — | |
| Blood replacement or postoperative haematoma | 4 (1.0) | 1 (0.2) | — | 0.135 | 0 (0) | 1 (0.4) | 1.000 | ||
| Cardiovascular complications | 0 (0) | 1 (0.2) | — | 0.348 | 0 (0) | 0 (0) | — | — | |
| Respiratory complications | 0 (0) | 0 (0) | — | — | 0 (0) | 0 (0) | — | — | |
| Anaphylactic reaction | 1 (0.2) | 0 (0) | — | 0.286 | 0 (0) | 0 (0) | — | — | |
| Wrong level surgery | 0 (0) | 0 (0) | — | — | 0 (0) | 0 (0) | — | — | |
| Complications within 3 months: | 43 (10.4) | 33 (7.0) | — | 0.073 | 27 (11.0) | 20 (8.1) | — | 0.360 | |
| Wound infection | 11 (2.7) | 8 (1.7) | — | 0.326 | 6 (2.4) | 6 (2.4) | — | 1.000 | |
| Urinary tract infection | 20 (4.8) | 17 (3.6) | — | 0.365 | 14 (5.7) | 9 (3.7) | — | 0.383 | |
| Micturition problems | 15 (7.6) | 3 (1.1) | — | <0.001 | 9 (3.7) | 1 (0.4) | — | 0.031 | |
| Pneumonia | 2 (0.5) | 5 (1.1) | — | 0.332 | 1 (0.4) | 4 (1.6) | — | 0.375 | |
| Pulmonary embolism | 1 (0.2) | 0 (0) | — | 0.286 | 0 (0) | 0 (0) | — | — | |
| Deep venous thrombosis | 2 (0.5) | 0 (0) | — | 0.131 | 2 (0.8) | 0 (0) | — | 0.500 | |