Extraforaminal Cervical Selective Nerve Root Block-Description of a Posterolateral Approach With Cone Beam-Based CT Guidance.

Background: Cervical selective nerve root blocks (C-SNRBs) maintain utility for presurgical planning in patients with cervical radiculopathy. Traditional fluoroscopic or stationary computed tomography (CT)-guided methods have been associated with complications, including catastrophic neurologic insults, while ultrasound guidance has been investigated based on its theoretical advantages. Maximizing patient safety by obtaining superior anatomic and procedural details promotes the exploration for better alternative guidance.

Methods: We describe a novel approach of posterolateral (PL) extraforaminal (EF) C4 SNRB using cone beam-based CT (CBCT)/fluoroscopy, which was performed on 3 separate occasions for 1 patient with suspected right C4 radiculopathy for presurgical evaluation. CBCT/fluoroscopy uniquely provides the function of both CT and fluoroscopy using a C-arm machine. It allows precise 3-dimensional needle planning and sophisticated 2-dimensional needle guidance, while ensuring tight needle control and detailed monitoring of contrast spread.

Results: A successful right C4 SNRB was repeatedly achieved, as evidenced by postprocedural paresthesias over the C4 dermatomal distribution and periradicular contrast spread. Additionally, the patient reported symptomatic relief (with regard to pain scores and neck range of motion), leading to cancelation of his surgical plan.

Conclusion: We propose the PL-EF approach as the safest protocol for C-SNRBs. When compared with fluoroscopy or CT, CBCT/fluoroscopy is an advanced imaging system that provides superior anatomic neurovascular detail, while offering precise needle control, contrast media monitoring, and easy operation in an office setting. These advanced features support it as the ideal guidance method for maximizing both the safety and efficiency of the PL-EF C-SNRB approach. However, the claimed advantages cannot be concluded without increasing its accessibility to pain specialists and conducting a prospective study with a large sample size.