6.8. Learning the contralateral stage of bilateral decompression

When learning bilateral decompression through a unilateral approach, particular attention is paid to crossing to the opposite side. Before surgery, MRI should be used to identify compression in the central canal and each lateral recess and to assess the bony and ligamentous components of stenosis. These findings are correlated with the endoscopic view at each stage of the procedure.

When crossing to the opposite side, familiar anatomical structures are viewed from a different angle. The surgeon must learn to recognize them after repositioning the endoscope and to determine the direction of instrument movement relative to the midline. Identifying the contralateral lamina, articular processes and ligamentum flavum attachments is particularly important [1]. The sequence of bone resection and ligament mobilization is described in §6.6. During training, each subsequent movement should be based on a clear understanding of the structure in view and the location of the instrument tip.

For instructional video review, it is useful to isolate the stages of reaching beneath the base of the spinous process, crossing to the opposite side and opening the contralateral lateral recess. These segments are reviewed for maintenance of orientation, instrument position and the moments when the viewing direction had to be changed to continue. The final decompression view is correlated with the preoperative MRI, assessing the central canal and each lateral recess separately.

References

1. Jang J.W., Chough C.K., Lee D.G., Park C.K. Lumbar Stenosis: Central and Lateral Recess Stenosis. In: Unilateral Biportal Endoscopic Spine Surgery: Basic and Advanced Technique. Springer; 2022. P. 73–85; contralateral decompression and anatomical landmarks: pp. 78–79, 84. Book chapter.

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