Motor and sensory examinations were graded by the operating surgeon as improved, unchanged, or worse. Patients' outcomes were assessed using a modified Odom's criteria. Radiographs included standing anteroposterior, lateral lumbar views, and dynamic flexion/extension radiographs for determination of the stability status. In addition to radiographic analysis, postoperative follow-up evaluation included a review of medical records and a postoperative visit to the outpatient clinic. They were then followed up at 1, 3, 6, and 12 months postoperatively, and then annually. Patients underwent postoperative radiograph prior to discharge. B : Photographs after ventral durotomy showing the disc removal by pituitary forceps through the dural hole. A : Photograph after laminectomy and dural opening demonstrating central bulging of the ventral dura. Adequate decompression with removal of calcified disc fragments and osteophytes was accomplished after meticulous dissection of dense adhesions between the disc herniation and the dural sac. An intentional durotomy, over its maximal bulging of the ventral dura, was performed ( Fig. After laminectomy, the incised dorsal dura was tacked, and the cauda equina rootlets were gently retracted. If dural sac or root retraction was not possible due to a large-sized central disc herniation, a transdural approach was selected to reduce the risk of nerve root injury ( Fig. Bilateral laminectomy was chosen if the patient complained of bilateral radiating pain. After retracting the compressed dural sac and discectomy, the nerve root was decompressed positively. Unilateral hemilaminectomy in symptomatic lesions and medial resection of the zygoapophyseal joints were performed in order to gain sufficient exposure of the discs. The accurate level of herniated disc was checked by intraoperative fluoroscopy. Under general anesthesia, the patient is usually prone positioned on an operating frame. Three surgical methods that included unilateral laminectomy, bilateral laminectomy, and a transdural approach were used. Disc consistency, direction, and size were also investigated on T2WI of MRI.Īll patients underwent a discectomy via a posterior approach. On preoperative magnetic resonance (MR) imaging or computerized tomography (CT) scan, we measured the area of the spinal canal and protruded disc material at the compressive level. Accurate distribution of sensory change was also evaluated. Preoperative data collected during review of patient medical records included the presence or absence of lower back and radicular pain, motor or sensory deficit, reflex changes, and sphincter dysfunction. Patients with the following conditions were excluded : obvious spondylosis or ossification of the ligamentum flavum or far lateral disc herniation. We retrospectively reviewed the medical records, radiological examinations and operative findings of 41 patients with symptomatic L1-L2 and L2-元 disc herniation who underwent surgery in our institute between January 1998 and December 2007. In this article, through retrospective review of our patients' data, we investigated the clinical features and surgical outcomes of upper lumbar disc herniations, and evaluated the predictive factors for determination of surgical methods. Because of this unique anatomy, selection of a surgical approach is difficult. Lengths of the lamina are shorter, location of pain varies, and direct cord compression may occur. Spinal canals are narrower than those of lower levels, which may compromise multiple spinal nerve roots or conus medullaris. Incidence of herniated upper lumbar discs defined as only L1-L2 and L2-元 are known to comprise approximately 1 to 2% of all herniated lumbar discs 5, 10).Ĭompared with those of lower levels, upper lumbar disc herniations have a less favorable outcome after surgery 16). Therefore, the 元-L4 level might be excluded from the upper lumbar disc. However, the anatomical characteristics of 元-L4 discs are more similar to lower levels, and its surgical outcome is significantly different from that of L1-L2 and L2-元 13, 17). Among these reported cases, herniations at the 元-L4 level comprise 70-83% of all upper lumbar disc herniations 2, 15, 19). Upper lumbar disc herniations have been reported to occur with a frequency of less than 5% of all disc herniations 2, 17). Most previous studies of upper lumbar disc herniations included the L1-L2, L2-元, and 元-L4 levels. Upper lumbar discs have been reported as only L1-L2 and L2-元 by some authors, and by others as T12-L1, L1-L2, and L2-元 3, 5, 8). ![]() Use of the term "upper lumbar" disc has been controversy. Compared to the lower one, upper lumbar spine results in fewer cases of spondylosis, disc generation, and fewer herniated discs. Due to the unique anatomy of the upper lumbar spine, upper lumbar disc herniations are different from those that occur at lower levels of the lumbar spine.
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