Endoscopic Laser Foraminoplasty Clinical Outcomes
A Treatment Concept and 2 Year Outcome Analysis
Aware state surgery has been used in the Spinal Foundation to identify the source of spinal pain in over 4,000 patients as part of a process termed Viviprudence. This process consists of clinical analysis, dynamic radiology and (Computerised Axial Tomography (CAT) and Magnetic Resonance Imaging (MRI)) scanning tested by differential discography, endoscopy and patient feedback. This replaces guesswork with sighted diagnosis and allows keyhole tissue preserving surgery to treat compressive radiculopathy from disc protrusions, disc extrusions and sequestrations, (slipped discs) and also for Back Pain, Failed Back Syndrome, Failed Fusion Surgery, Perineural Scarring, Epidural Scarring, Multilevel Degenerative Disc Disease, Osteophytosis, Disc Settlement, “Black” Disc syndrome, Lateral Recess Stenosis and Dynamic Olisthesis (“Instability”).
Endoscopic Minimal Invasive Spinal Surgery has led to the identification of new pathology causal of back pain and referred pain and consequently this has led to the refinement of the inclusion criteria for Laser Disc Decompression and Endoscopic Laser Decompression & Foraminoplasty and the treatment techniques.
Since 1992, Endoscopic Laser Foraminoplasty has been developed to explore the intervertebral foramen, epidural space and intradiscal space via the postero-lateral transforaminal route. The objective has been to combine the endoscopic aware state definition of the source of pain with feedback led decompression of the foramen, mobilisation and neurolysis of the exiting and transiting nerves and ablation of osteophytes and removal of degenerate products from within the disc and other causes of the ‘failed back syndrome’, all under endoscopic visualisation.
Clinical Outcomes
This prospective study involved “daycase” Endoscopic Laser Foraminoplasty performed on 101 males, and 99 females with an average age of 56 years (22-83 years). They were followed for an average period of 34 months (26-43 months). The average preoperative duration of symptoms was 5.6 years (5 -11 years). 46 Patients had had 1 – 4 previous open operations. 14 patients were on narcotic analgesics prior to surgery. At other centres, 106 of these patients were evaluated and open surgical procedures were not deemed appropriate or likely to benefit.
96% cohort integrity was maintained at the final follow up. Back, buttock and leg pain were separately compared and analysed using the Oswestry Disability Index, a Patient Satisfaction Scoring Scale, Visual Analogue Pain Scale and a patient Target Achievement Score. Using an Oswestry Disability Index of 50 or more to determine good and excellent Outcomes, 55% of patients exceeded this score for back pain; 52% for buttock pain; and 53% for leg pain. In patients with one prior operation the corresponding figures were 51%, 33%, and 29%.
These results indicate that Endoscopic Laser Foraminoplasty provides a minimalist means of exploring the extraforaminal zone, the foramen and the epidural space and performing discectomy, osteophytectomy and neurolysis. It incorporates the prophylactic advantage of foraminal undercutting and provides a promising means of identifying and treating the pain of ‘failed back surgery’ and back pain and sciatica of indeterminate origin. It serves to identify and localise the source of pain generation. Endoscopic Laser Foraminoplasty avoids the morbidity associated with open spinal surgery and serves as a useful means of effecting ‘keyhole’ neurolysis without extensive exploration and fusion. Current improvements in equipment promise wider application and more encouraging results in the future under the surgical name of Endoscopic Laser Decompression & Foraminoplasty.
Discussion
The management of back pain has remained a source of speculation and research. Its impact on modern industrial society has been well established. Approximately 2 to 5 % of people suffer from acute back pain every year. The majority of these patients recover fully while 10 to 25% have residual complaints. 0.5% of these patients have pain and neurology requiring surgery whilst others slip into chronicity. Chronic back pain does have a significant impact on the individual and associated family involving fear and worry and altering the perception of pain and degrading the quality of life.
Traditional methods of treatment such as osseous decompression, microdiscectomy to decompress nerve roots, and spinal fusion, Total Disc Replacement have provided the standard armamentarium of the spinal surgeon.
The choice of conventional treatment has depended on the surgeon’s knowledge base and the information derived from the use of inert diagnostic tools used to identify the source of pain. Open surgical procedures for the management of spinal pain give unpredictable results and may cause additional morbidity in their own right. Widely varying claims of success are attributed to these techniques but recent Randomised Controlled Clinical Trials have shown that Instrumented Lumbar Fusion is only equivalent to Cognitive Behavioural Therapy in clinical OUTCOME.
In the quest to reduce tissue trauma and morbidity, decompressive disc procedures such as fenestrectomy and microdiscectomy are providing encouraging results.
The deployment of endoscopic techniques in the spine has allowed visual inspection of the foraminal contents and the disc through the ‘key hole’ with the patient in the aware state providing feed back pointing to the pain source, and intradiscal decompression to be effected as a consequence.
Laser as a tool for “precision” tissue ablation has been tried in several surgical specialities with encouraging results. In 1984 the laser disc decompression was introduced by Daniel Choy and others and we combined with endoscopy to effect intradiscal clearance and ultimately extradiscal clearance in the form of Endoscopic Laser Decompression & Foraminoplasty. Laser is highly effective in ablating bone osteophytes (spurs), undercutting the foramen and ablating scar tissue and so provides means of exploring the foramen and extraforaminal zone and epidural space by the postero-lateral route in the aware state and treating the pain sources highlighted by the patient.
Our endoscopically derived appreciation of the mechanisms of nerve pain, pain mediators in and around the spinal canal and pain modulation in the peripheral and central nervous system have cautioned us against excessive dependence on traditional mechanical concepts of back pain.
