Uni-portal non-coaxial spinal endoscopic surgery via crossing midline approach for cervical radiculopathy: a case series of four patients.

Introduction: Cervical radiculopathy typically presents with pain, numbness, and weakness in the affected nerve root distribution. When caused by bony foraminal stenosis, conventional posterior keyhole foraminotomy often necessitates extensive facetectomy, risking spinal instability. A modified approach preserving facets is therefore needed. This study assessed the feasibility and preliminary outcomes of uni-portal non-coaxial spinal endoscopic surgery (UNSES) with a crossing midline approach (CMA) for cervical radiculopathy. Methods: Four patients with cervical radiculopathy caused by bony foraminal stenosis underwent nerve root decompression via the CMA between March 2025 and April 2025. In this retrospective, single-center study, patients with a history of infection, trauma, or tumor were excluded. The surgical procedure involved three key steps: removal of V-point osteophytes using a high-speed drill, excision of herniated nucleus pulposus, and preservation of the lateral bony structure of the ipsilateral facet joint. Technical details of this novel approach are comprehensively described. Results: Mean operative time was 168.5 (98, 196) mins with blood loss of 15 (5, 50) mL. At 1 month, the Visual Analogue Scale (VAS) scores improved by 1 (0, 5) points and the Japanese Orthopaedic Association (JOA) scores improved by 16 (14, 17) points. Facet joint resection rate averaged 40.61% (18.21%, 47.05%). All four incisions healed within 2 weeks without complications at the 6-month follow-up. Conclusion: The UNSES technique via the CMA approach successfully achieves nerve root decompression while maximizing cervical facet joint preservation, without compromising spinal cord or adjacent neurovascular integrity. Importantly, it establishes a novel minimally invasive surgical option for cervical radiculopathy.