C5 palsy following one- or two-level anterior cervical discectomy and fusion: Incidence and neurological recovery in a retrospective neurosurgical multicenter study

Background: C5 palsy is a frequent complication following cervical spine surgery, particularly after posterior approaches. Although several risk factors have been proposed, the incidence of C5 palsy after anterior cervical discectomy and fusion (ACDF) remains less well understood. This study aims to elucidate the risk factors and neurological recovery associated with C5 palsy following ACDF.

Methods: A total of 330 patients who underwent one or two-level ACDF between January 2018 and December 2022 across three institutions within the neurosurgical training program were retrospectively included and analyzed. Demographic, surgical, and radiological data were collected.

Results: Sixteen (4.8 %) patients developed postoperative C5 palsy, with a significantly high incidence observed in patients exhibiting preoperative symptoms (radiculopathy or radiculomyelopathy) and undergoing two-level ACDF (p-values 0.008 and 0.018, respectively). No other demographic or radiological factors were associated with C5 palsy. Eleven of 16 (68.8 %) patients experienced C5 palsy within 1 day post-surgery (early-onset group), whereas the remaining five developed symptoms between 4 to 15 days post-surgery (late-onset group). At one year post-surgery, the late-onset group demonstrated superior recovery from C5 palsy compared to the recovery noted in the early-onset group (100 % vs 44.4 %).

Conclusions: Surgeons should be cognizant of the potential for C5 palsy following one- or two-level ACDF, despite generally favorable neurological outcomes. The timing of C5 palsy onset post-ACDF, potentially influenced by mechanisms such as direct injury and ischemia-reperfusion injury, could impact the recovery prognosis. Careful surgical procedure might be the key to success.