Table 5.

Adverse Events by Treatment

Adverse Event	Intraarticular Facet Block (n = 91)	Medial Branch Block (n = 92)	Saline Block (n = 47)	Radiofrequency Denervation (n = 136)
Serious adverse event*	0	0	0	4 (3%)†
Minor adverse event‡	5 (6%)	8 (9%)	2 (4%)	7 (5%)
Worsening pain
Neurologic	1 (1%)	2 (2%)	–	1 (1%)
Nonneurologic	1 (1%)	1 (1%)	–	1 (1%)
Neuritis	–	–	–	3 (2%)

^*Serious adverse events were as defined by the Food and Drug Administration (resulting in death, life-threatening adverse drug experience, inpatient or prolonged hospitalization, disability or permanent damage, congenital anomaly or birth defect, or required intervention to prevent permanent impairment or damage).

^†Includes three events that were judged to be unrelated to procedure (emergency department visit with unspecified chest pain two months after procedure, admission for suicidal ideation unrelated to low back pain, and suicide unrelated to low back pain). One patient went to the emergency department for suspected medial branch neuritis that resolved within four days.

^‡Included rash, localized skin infection, vasovagal episode, nausea, numbness, and worsening pain.