Here are links to articles that I find relevant to the current state of endoscopic spine surgery

Dutch endoscopic non-inferiority trial of endoscopic versus microsurgical discectomy from the British Medical Journal

Medial Branch Transection

Endoscopic medial branch transection history and review World Neurosurgery 2022
Percutaneous rhizotomy versus endoscopic medial branch transection.  Li, China.
Injection worksheet

Ruetten and Komp Opus

Ruetten and Komp 463 Uniportal Transforaminal cases.  Spine 2005
Ruetten and Komp, degenerative central stenosis treated endoscopically.  74 patients, 2 year results
Ruetten and Komp stenosis RCT: endoscopic versus microsurgical technique.  135 patients, 2 year results
Ruetten and Komp, posterior cervical foraminotomy. 
Ruetten and Komp, endoscopic facet cyst excision
Ruetten and Komp, endoscopic thoracic discectomy.  26 patients

Anatomic studies

Medial Branch Anatomy Article
Microscopic anatomy of the neuroforamen

Ultrasound

Ultrasound of the Spine

Articles for convincing your hospital to buy endoscopic equiopment

90 day Emergency Room Visits and Readmissions after Endoscopic Spine Surgery

Costs of endoscopic versus microdiscectomy: cost per case for ED and MD was $3915 ± $1025 and $3162 ± $954