Uniportal Endoscopic Lateral to Medial Direction Transforaminal Lumbar Interbody Fusion: A Case Report and Technical Guide for Navigating Through Landmarks in Left Lumbar 4/5 Post Laminotomy Revision Lumbar Fusion Surgery

Post lumbar laminotomy anatomical changes can be disorienting to uniportal spinal endoscopist. This which led to many open conversionconversion to open surgery to verify landmarks. Isthmus tends not to be violated inis usually preserved in laminotomy and it can be used as a useful landmark for endoscopic fusion surgery. Unlike tubular microscopic surgery, endoscope possess more mobility; conveniently navigating through the identifiable anatomical landmarks in revision surgery with minimal fluroscopy. Uniportal Endoscopic Lateral to Medial Direction Transforaminal Lumbar Interbody Fusion, is a useful revision surgery technique with isthmus as reference point, it had not been described in literature. Case Presentation A 66 years old lady with two previous lumbar decompressive surgery to left L4/5 presented with neurogenic claudication and instability. She was diagnosis was to have L4/5 post-surgical spondylolisthesis with stenosis. She Informed consent was obtained consented for left L4/5 revision uniportal endoscopic lateral to medial direction transforaminal lumbar interbody fusion, Endo (LM)-TLIF. Procedure started with drilling isthmus with from lateral to medial direction using exploratory bone drilling dissection technique to decompress and explore residual bony anatomical landmark. With proper definition of anatomical margins of intervertebral disc space, endoscopic guided discectomy, end plate preparation, cage and percutaneous pedicle screws insertion were done with aid of fluoroscopy and endoscopy to perform spinal fusion. Patient did well post operatively without any intraoperative complication.Conclusion Endo (LM)-TLIF is a viable, safe and efficacious method to explore a potentially challenging post-surgical anatomy around spinal canal in revision lumbar fusion