ABSTRACT
Posterior cervical foraminotomy allows decompression of the nerve root with preservation of the motion. Conventional posterior approaches have the disadvantage of detaching the extensor cervical muscles from the laminae and the spinous processes. The aim of this work is to present a new minimally invasive posterior approach avoiding detachment of muscles for the treatment of cervical radiculopathy and myelopathy. Twenty-five patients suffering from cervical radiculopathy [12 patients] and myelopathy [13 patients] were operated according to this technique. In principle, this technique secures access to the diseased spinal segment via a percutaneously placed working channel [11 mm outer diameter and 9 mm inner diameter]. The cervical paraspinal muscles are not deflected, but just spread between their fibres by special dilators. All further steps are performed through this channel under control of 3-dimensional vision through the operating microscope. The average follow up period was 15 months, and patients were evaluated using a modified version of Oswestry Index, called the Neck Disability Index [NDI] and the Visual Analogue Scale [VAS] for neck and arm pain. The mean NDI [P< 0.0001] improved from 38.89 [pre-operative] to 9.43 [post-operative]. The VAS for arm pain [P<0.001] and for neck pain [P<0.001] showed also marked post-operative improvement. Complete recovery of the pre-operative neurological deficit was found in 7 patients while the remaining 18 patients showed improvement of the neurological symptoms during the follow up period. There were no intra-operative or post-operative complications and no re-operation. The preliminary experience with this technique seems to promise, that this less invasive technique is a valid alternative to the conventional open exposure for treatment of lateral disc prolapses, foraminal bony stenosis and central posterior ligamentous stenosis of the cervical spine