Table 3.

Comparison of post-operative outcomes between the durotomy and no durotomy groups.

Outcome	No durotomy (n=371)	Durotomy (n=38)	p-value
Postoperative complications¶
Nerve root injury	0 (0%)	0 (0%)
Wound hematoma	4 (1%)	0 (0%)	0.81
Wound Infection	7 (2%)	2 (5%)	0.43
Other	20 (5%)	4 (11%)	0.34
None	325 (88%)	29 (78%)	0.15
Post-operative mortality (death within 6 weeks of surgery)	1 (0.2%)	0 (0%)
Post-operative mortality (death within 3 months of surgery)	1 (0.2%)	0 (0%)
Additional surgeries (1-year rate)∥	20 (5%)	1 (3%)	0.461
Additional surgeries (2-year rate)∥	28 (8%)	3 (8%)	0.959
Additional surgeries (3-year rate)∥	41 (11%)	3 (8%)	0.554
Additional surgeries (4-year rate)∥	49 (13%)	3 (8%)	0.363
Recurrent stenosis/progressive lesthesis	22 (6%)	1 (3%)
Pseudoarthrosis/fusion exploration	0 (0%)	0 (0%)
Complication or Other	15 (4.1%)	2 (5.3%)
New Condition	7 (1.9%)	1

* Surgical information was available for 371 non-durotomy and 38 durotomy patients.

^¶Complications or events occurring up to 8 weeks after surgery are listed. There were no reported cases of bone-graft complication, cerebrospinal fluid leak, paralysis, cauda equina injury or pseudarthrosis.

^∥Rates of repeated surgery at 1, 2,3,and 4 years are Kaplan-Meier estimates. P values were calculated with the use of the log-rank test. Numbers and percentages are based on the first additional surgery if more than one additional surgery.