Endoscopic cervical decompression

Endoscopic cervical decompression

for treating cervical disc herniations

Research by Dr Stephan Hellinger, Munich, Germany, entitled, ’Selective percutaneous endoscopic cervical decompression and discecctomy in the treatment of disc herniation in the cervical spine’, endoscopic decompression and nucleotomy proved to be a safe and efficient alternative to conventional anterior cervical discetomy, with or without fusion. The procedure was recently demonstrated at the 1st International Hands-on Workshop on Endoscopic Cervical Disc Surgery meeting, held in September 2007 in Muster, Germany, by Professor Sang Ho Lee, Seoul, Korea, who is one of the oldest spine surgeons performing this technique. According to Hellinger, there is a high incidence of cervical discogenic pain symptoms in the population, and it is estimated that one in five people in Germany who visit an orthopaedist, present with the symptoms of a cervical disc syndrome. The treatment of cervical discogenic diseases makes high demands in terms of both diagnostics and therapy, however diagnostics has been made easier by improved imaging and the enhancement of neurological measuring methods. Consequently, there is now interdisciplinary consensus that the principal pathologic causes can be reliably identified. "With the aid of appropriate conservative therapy, approximately 80% of all cervical syndromes can be cured. Only once all the conservative and semi-invasive procedures have been exhausted should surgery be considered," he explained. As a bridge between open and percutaneous therapy, endoscopy of the cervical spine started to be used at the beginning of the 1990s, following good experiences on the lumbar spin, explained Hellinger. The indications for selective percutaneous endoscopic cervical decompression are neck radicular pain, symptoms of segmental dysesthesia, and motor deficits matching the pathologic segment, conservative therapy-resistant vertebrogenic headache with reliable imaging, disc herniation confirmed by magnetic resonance imaging (MRI) or computed tomography (CT), with associated clinical picture, damage in adjoining segments after preceding fusion, with corresponding clinical picture, and multisegment disc herniations. This method cannot be used in cases of serious cervical spinal stenosis, migrated free sequestra, pronounced spondylosis with large osteophytes, and calcifications of the posterior spinal ligament. The objective of the investigation was to create an adequate working space in front of the telescope while preserving the minimally invasive approach. From a group of 30 cases, 14 patients underwent percutaneous microlaser disc nucleotomy (PLDN) and 16 patients underwent percutaneous endoscopic cervical discectomy (PECD). After six weeks, the McNab questionnaire was used to determine good or excellent results, in which 65% was recorded for the PLDN group, and 76% for the PECD group. Using the Visual Analog Scale (VAS), the pain improved in the PLDN group from 8.4 to 3.2 and from 8.6 to 2.4 in the PECD group. By both methods neurological deficits disappeared. This was achieved by the use of dilation sheaths, which force the base plate and upper plate apart in the manner of a Caspar retractor and permit a working field of 5mm or 6mm. Hellinger explained that the visualisation is sufficient to expose the ventral epidural space, and his aim was to compare both methods in the outcome and the safety. Removal of disc material is limited to the pathologic part, in a similar way to arthroscopic meniscus surgery, said Hellinger. Equally, the surgeon has to become accustomed to the fact that limited viewing fields are lined up, rather as in joint arthroscopy. An irrigation system is used to rinse the ablated disc material out of the viewing field and to achieve partial haemostasis. Endosopic cervical discectomy can also be performed using a gas medium. As further instruments for endoscopic intervertebral disc surgery are developed, the scope of application can undoubtedly be extended.