Foraminoplasty with Laser

D. WERNER

 

Technical advances in the last few years have shown that surgeries with increasingly smaller incisions can be as successful as open surgery. The purpose of the small incisions is not the demonstration of special skills, but the possibility of accessing the place of events without causing damage to the structures not involved in the pathology. Properly positioning the endoscope in front of the foramen as well as purposefully preparing the intraforaminal structures and the bony boundaries allow for a significant expansion of treating pathological transformations of the spinal chord. Foraminoplastic surgery has proven to be especially successful in avoiding fusions. A prerequisite for enlarging the foramen is the assured stability of the affected vertebra segment. The clinical condition of the vertebra is of utmost importance. There must not be any clinical indication of segment instability, i.e. an indication of spondylothesis. If there are indications of a decreased line segment, or if the patient suffers from isolated back pain after standing erect for an extended time period, the surgeon should refrain from foraminoplasty and consider stabilizing the segment.  Technical approaches to examining the foramen will vary depending on the operating surgeon. After primarily accessing the pathological structures of the interarticular disk, the surgeon may then move toward the foramen and remove the pathological transformations in that area. It is also possible to primarily access the foramen and then remove pathological structures of the interarticular disk.

 

The  most common pathological symptoms in the foramen are intraforaminal disc collapse, extraforaminal disc collapse, foraminal stenosis of the interconnective tissue, foraminal stenosis of the bone by osteophytes of the facet joint, foraminal stenosis of the bone caused by the decreased height of the interarticular disk, and hypertrophy of the facets. In special cases, intraspinal stenosis caused by epidural cysts or migrated fragments need to be addressed. In this case, the pathology is located directly on the interarticular disk or is directly linked to it. The technique of removing migrated fragments is not easy and requires an adequate amount of experience.

 

In many cases, foraminoplasty for the purpose of enlarging the transforaminal space, i.e. the improvement of the transforaminal nerve passage, leads to a significant alleviation of discomfort. What happens in this case is the resection of intraforaminal connective tissue and, in some cases, also the resection of bone and portions of the posterior ligaments and/or portions of the thickened capsule of the facet joints. Especially if the degeneration of the interarticular disk has advanced and a significant decrease of height has taken place, the posterior ligament will thicken and lead to a narrowing of the foraminal nerve passage. In this case, a bilateral resection or, if the symptoms are limited to one side, a unilateral resection of the ligament has proven to be helpful. In this case, laser techniques have been beneficial. The use of laser allows for a well-defined resection that avoids causing destruction or harm to the surrounding structures. The same holds true for resecting osteophytes in the area of the facet  joints  or a thickened facet joint capsule. Laser techniques have been especially useful in the resection of bone. This is due to the significantly reduced risk of hemorrhage and the ability to take a very specific aim in the mechanical excision.