Surgical management of back and leg pain is evolving and changing due to a better understanding of the patho-anatomy well correlated with its pathophysiology. Pain is better understood with in vivo visualization and probing of the pain generators using an endoscopic access rather than just relying on symptoms diagram and image correlation. This has resulted in a shared decision making involving patient and surgeon, focused on a broader spectrum of surgical as well as non-surgical treatments, and not just masking the pain generator. It has moved away from decisions based on diagnostic images alone, that, while noting the image alterations, cannot explain the pain experienced by each individual as images do not always show variations in nerve supply and patho-anatomy.
The ability to isolate and visualize “pain” generators in the foramen and treating persistent pain by visualizing inflammation and compression of nerves, serves as the basis for transforaminal endoscopic (TFE) surgery. This has also resulted in better pre surgical planning with more specific and defined goals in mind. The “Inside out” philosophy of TFE surgery is safe and precise. It provides basic access to the disc and foramen to cover a large spectrum of painful pathologies.
Conventional fluoroscopically guided continuous radiofrequency (CRF) and pulsed Radiofrequency (PRF) lesioning of the medial branch, dorsal ramus, a standard technique to treat facet pain, is compared to an endoscopic visually guided technique. The endoscopic technique (Figure 1)is designed to ablate a larger area of the transverse process where the medial branch crosses to innervate the facet. Endoscopically guided visualization provides confirmation of nerve ablation or transection in the most common location of the branches of the dorsal ramus innervating the facet joint.
The most common causes of failed back surgery are residual or recurrent herniation, foraminal fibrosis and foraminal stenosis that is ignored, untreated, or undertreated. Residual back ache may also be from facetal causes or denervation and scarring of the paraspinal muscles. The original surgeon may advise his patient that nothing more can be done on the basis of his opinion that the nerve was visually decompressed by the original surgery, supported by improved post-op imaging and follow-up studies such as EMG and conduction velocity studies. Post-op imaging or electrophysiological assessment may be inadequate to explain all the reasons for residual or recurrent symptoms.
Treatment of Failed back surgery by repeat traditional open revision surgery usually incorporates more extensive decompression causing increased instability and back pain, therefore necessitating fusion. The authors, having limited their practice to endoscopic MIS surgery over the last 15-20 years, report on their experience gained during that period to relieve pain by endoscopically visualizing and treating unrecognized causative patho-anatomy in FBSS.
Objective: to describe the developing changes in Selective Endoscopic Discectomy TM (SED TM ) to correlate endoscopic spinal surgery with the disc pathology identiﬁed by Evocative Discography TM (ED TM ) and direct observation.
The patho-anatomy in an aging spine is partly defined by Rauschning’s anatomic cryosections. Theories of pain generation and principles of minimally invasive spine surgery are suggested by close examination of these specimens. If the visualized patho-anatomy can be studied in vivo in a partially sedated patient by spinal probing, spinal pain can be better understood, and rational endoscopic treatment options may then evolve.1 A 1997 IRB-approved study provided evidence that endoscopic transforaminal surgery was feasible for the treatment of a wide spectrum of degenerative conditions in the lumbar spine. The technique incorporated evocative chromo-discography to correlate reproduction of pain with in-vivo probing of patho-anatomy. Laser and radiofrequency ablation augmented mechanical decompression to obtain pain relief.1-3 Endoscopic visualization of patho-anatomy ranging from annular tears to spondylolisthesis and stenosis provided clinical evidence that foraminal decompression, ablation, and irrigation could effectively treat these visualized painful conditions with minimal morbidity. This resulted in a better understanding of the pain generators in the lumbar spine, opening up options for surgical pain management.1-5 The procedure does not burn any bridges for more traditional surgical techniques. The learning curve may be steep for some and long for others, but results are very good, concomitant with each individual surgeon overcoming his personal learning curve.