Chapter Clinical Summary
Academic synthesis, diagnostic methodology, and surgical recommendationsAnterior cervical endoscopic surgery emerged from the desire to achieve targeted anterior neural decompression while eliminating the fusion-related morbidity of anterior cervical discectomy and fusion (ACDF), such as adjacent segment disease, nonunion, and hardware complications. By utilizing continuous fluid irrigation, high-definition optical magnification, and narrow working channels, anterior endoscopic approaches allow direct discectomy or focal transcorporeal decompression through minimal muscle dissection and preserving the majority of the intervertebral disc and adjacent motion segment. However, working in the anterior cervical corridor demands absolute mastery of fascial planes, protection of the carotid sheath and aerodigestive viscera (esophagus and trachea), and continuous vigilance regarding the recurrent laryngeal nerve and vertebral artery. The safety of the procedure depends on strict clinicoradiological patient selection, exact pre-incision trajectory planning, precise bony drilling, and meticulous control of fluid irrigation pressure.
Present the technical principles, anatomical corridors, indications, and limitations of anterior cervical endoscopic surgery. The reader will learn to plan and execute both transdiscal and transcorporeal approaches, safely manage anterior visceral and neurovascular structures, ensure complete neural decompression under direct vision, and prevent complications including esophageal perforation, recurrent laryngeal nerve palsy, dural tear, and epidural hematoma.
The anterior cervical endoscopic approach addresses anterior pathology without necessitating formal interbody fusion or arthroplasty. By preserving unaffected disc architecture or drilling a targeted transcorporeal bone channel, the procedure maintains segmental biomechanics and eliminates plate- or cage-related morbidities.
Ideal indications include soft, central, paracentral, or foraminal cervical disc herniations refractory to conservative treatment, producing radiculopathy or mild localized myelopathy. Absolute contraindications include multi-level compressive myelopathy, severe cervical instability, fixed kyphotic deformity, disc height loss >50%, and extensive retrovertebral OPLL requiring corpectomy.
In the transdiscal approach, the endoscope enters the disc space along a gentle trajectory to extract herniated fragments while sparing normal disc tissue. In the transcorporeal approach, a narrow (3.5–4.0 mm) drill channel is created through the vertebral body directly to the retrovertebral herniated fragment, leaving the intervertebral disc completely untouched.
Under biplanar fluoroscopic guidance, the prevertebral space is developed between the sternocleidomastoid/carotid sheath laterally and the trachea/esophagus medially. Digital palpation and blunt dissection confirm the midline. Working cannulas are docked with constant visceral awareness, using blunt obturators to prevent esophageal laceration.
Complications include esophageal or tracheal injury, recurrent laryngeal nerve neuropraxia, carotid or vertebral artery injury, incidental durotomy, epidural hematoma, and transient dysphagia. Maintaining continuous low-pressure irrigation prevents fluid extravasation into the deep neck fascial spaces.
In clinical practice, anterior cervical endoscopy is considered when a single-level soft disc herniation causes severe radiculopathy or localized cord compression in a patient with preserved cervical lordosis and stable alignment. Preoperative MRI and CT are essential to measure disc height and uncinate morphology. In younger patients or athletes desiring rapid recovery without fusion, the transcorporeal approach preserves intact disc tissue. Intraoperatively, the surgeon must bluntly clear the prevertebral fascia and maintain gentle medial visceral retraction. Once docked, bone drilling is performed under continuous fluid flow and direct magnification until the posterior longitudinal ligament is identified. Opening the ligament releases the herniated fragment. Final verification ensures that the thecal sac and exiting nerve root are completely decompressed and pulsating freely without bleeding.