New Classification System of Minimal Invasive Techniques based on the Location of the Pathologic Lesions in the Spinal Canal

Abstract

Introduction Minimal invasive procedures in spine surgery to remove pathologies located in the spinal canal have undergone significant development in the recent times. These procedures have the common aim of avoiding biomechanical complications associated with some traditional destructive methods and improving efficacy. These new techniques prevent damage to crucial posterior stabilizers, and preserve structural integrity and stability of the spine. In this review, authors first provide a classification system of minimal invasive techniques based on the location of the pathologic lesion to be treated, to help the surgeon in selecting the appropriate procedure. Material and Methods A classification system was introduced, which pairs various intraspinal pathologic lesions, taking into account their location topography relative to the spinal cord, with the appropriate minimal invasive techniques. Classification of the different surgical methods is presented with the aim of helping the surgeon in selecting the appropriate minimal invasive procedure based on the location topography of the pathology in the spinal canal. This classification system can be applied in the daily routine of spine surgery. Results Lesions within the spinal canal may be segmental or longitudinal to the spinal levels, and axial or lateral relative to the spinal cord. The following four types of lesion locations are defined in the classification system: segmental-lateral, segmental-axial, longitudinal-axial, and longitudinal-lateral. Hemi–semi laminectomy (partial hemilaminectomy) and its variants are appropriate methods for the removal of various types of segmental-lateral located pathologies with preservation of dorsal spinal stability. Both unilateral and bilateral laminotomy for bilateral decompression can be used for the treatment of spinal stenosis, with good clinical outcomes. Foraminotomies with or without modifications are alternative surgical approaches for the treatment of segmental-lateral pathologies located in the neuroforamen. Split laminotomy and its variant, para split laminotomy are mainly recommended for the removal of longitudinal–axial located intraspinal lesions. Its “arch bone” modification enables the moderate enlargement of the spinal canal. Conclusion In summary, sufficient evidence is available for each minimal invasive techniques to be used as a clinically effective treatment option. Our classification system enables the surgeon to select and apply the appropriate minimal invasive technique and to remove the lesions located in the spinal canal. This overview of the minimal invasive techniques can be applied and recommended in the daily routine of spine surgery.