✓Discal cysts are rare lesions that can result in refractory sciatica. Because they are so rare, their exact origin and details of the clinical manifestations are still unknown. The authors report on five men treated for discal cysts. The mean age of the patients at the time of the surgery was 32 years (range 25–38 years). All patients suffered from lower-extremity pain and the results of the straight leg–raising test were positive in all cases. Three patients reported motor weakness and four had sensory disturbance—symptoms similar to those found in patients with lumbar disc herniation. Magnetic resonance imaging demonstrated spherically shaped extradural lesions of various sizes with low and high signal intensities on T1- and T2-weighted images, respectively. Discography revealed obvious communication between the cyst and the intervertebral disc with reproducible leg pain in all patients. All patients underwent posterior decompression and excision of the cysts either with or without additional discectomy. The radicular symptoms were remarkably improved in all patients immediately after surgery, and no recurrent lesions were noted during follow up.

We performed microscopic lumbar foraminotomy in all the patients diagnosed with degenerative lumbar foraminal stenosis (DLFS) and retrospectively reviewed the clinical outcomes and the factors influencing them. The preoperative Japanese Orthopaedic Association (JOA) score of 13.8 significantly improved to 21.9 postoperatively. Although leg pain reduced in 44 patients (95.7%) immediately after surgery, it recurred in 9 patients (19.6%). The recurrence frequency was significantly higher and the JOA score improvement ratios significantly lower in patients with degenerative lumbar scoliosis (DLS) than in those without DLS. Even among patients with DLS, those with \3°Cobb angle difference between the supine and standing positions showed satisfactory results, with no recurrence. In conclusion, microscopic lumbar foraminotomy for DLFS produced satisfactory clinical outcomes even in patients with DLS. However, the outcomes were poor in patients with unstable DLS.

The purpose of this study was to examine factors affecting the severity of neurological deficits and intractable back pain in patients with insufficient bone union following osteoporotic vertebral fracture (OVF). Reports of insufficient union following OVF have recently increased. Patients with this lesion have various degrees of neurological deficits and back pain. However, the factors contributing to the severity of these are still unknown. A total of 45 patients with insufficient union following OVF were included in this study. Insufficient union was diagnosed based on the findings of vertebral cleft on plain radiography or CT, as well as fluid collection indicating high-intensity change on T2-weighted MRI. Multivariate logistic regression analysis was performed to determine the factors contributing to the severity of neurological deficits and back pain in the patients. Age, sex, level of fracture, duration after onset of symptoms, degree of local kyphosis, degree of angular instability, ratio of occupation by bony fragments, presence or absence of protrusion of flavum, and presence or absence of ossification of the anterior longitudinal ligament (OALL) in the adjacent level were used as explanatory variables, while severity of neurological deficits and back pain were response variables. On multivariate analysis, factors significantly affecting the severity of neurological deficits were angular instability of more than 15°[adjusted odds ratio (OR), 9.24 (95% confidence interval, CI 1.49-57.2); P \ 0.05] and ratio of occupation by bony fragments in the spinal canal of more than 42% [adjusted OR 9.23 (95%CI 1.15-74.1); P \ 0.05]. The factor significantly affecting the severity of back pain was angular instability of more than 15°[ adjusted OR 14.9 (95%CI 2.11-105); P \ 0.01]. On the other hand, presence of OALL in the adjacent level reduced degree of back pain [adjusted OR 0.14 (95%CI 0.03-0.76); P \ 0.05]. In this study, pronounced angular instability and marked posterior protrusion of bony fragments in the canal were factors affecting neurological deficits. In addition, marked angular instability was a factor affecting back pain. These findings are useful in determining treatment options for patients with insufficient union following OVF.

Discal cysts are rare lesions that can result in refractory sciatica. Because they are so rare, their exact origin and details of the clinical manifestations are still unknown. The authors report on five men treated for discal cysts. The mean age of the patients at the time of the surgery was 32 years (range 25-38 years). All patients suffered from lower-extremity pain and the results of the straight leg-raising test were positive in all cases. Three patients reported motor weakness and four had sensory disturbance-symptoms similar to those found in patients with lumbar disc herniation. Magnetic resonance imaging demonstrated spherically shaped extradural lesions of various sizes with low and high signal intensities on T1- and T2-weighted images, respectively. Discography revealed obvious communication between the cyst and the intervertebral disc with reproducible leg pain in all patients. All patients underwent posterior decompression and excision of the cysts either with or without additional discectomy. The radicular symptoms were remarkably improved in all patients immediately after surgery, and no recurrent lesions were noted during follow up.