Table 5.

Results of recent large-scale contemporaneous studies evaluating outcome and recurrence after hemilaminectomy with fenestration.

Reference	Number of cases	Study design	Surgical approach	Recurrence rate	Fenestration-associated complications	Notes
Mayhew et al. (72)	229	Retrospective case series	Hemilaminectomy without fenestration for all cases.	19.2%	Not applicable	None
Brisson et al. (34)	265	Retrospective case series	Hemilaminectomy for all cases. Prophylactic blade or power-assisted fenestration at various sites	4.4%	Pneumothorax (n = 1) Hemothorax (n = 1)	Hemothorax secondary to collagenase used for chemonucleolysis
Forterre et al. (69)	19	Prospective cohort	Hemilaminectomy for all cases. Single site power-assisted fenestration of the herniated disc vs. no fenestration	No recurrence in fenestrated group; 60% recurrence rate in non-fenestrated group although only 30% were clinical	None	Recurrence followed by MRI, not just clinical signs
Brisson et al. (66)	207	Prospective, randomized trial	Hemilaminectomy for all cases. Randomized to either single (herniated site only) or multi-site fenestration (T11-L4)	7.5% for multi-site fenestration and 18% for single site fenestration	Hemorrhage during fenestration (n = 7) Nerve root trauma (n = 4) Broken curette tip within the disc (n = 1)	Recurrence rate includes only confirmed recurrences; 92% of recurrences at a non-fenestrated site
Aikawa et al. (73)	662	Retrospective case series	Hemilaminectomy for all cases. Fenestration of all sites T11-12 to L1-2; L2-3 and L3-4 also performed in some dogs	2.3% based on clinical signs and imaging; 10% based on clinical signs alone	Intraoperative iatrogenic disc extrusion into the vertebral column (n = 1)	None

Results are compared to recurrence rate noted by Mayhew et al. without fenestration.