Background: Comparatively little is known about the relation between the sagittal vertical axis and clinical outcome in cases of degenerative lumbar spondylolisthesis. The objective of this study was to determine whether lumbar sagittal balance affects clinical outcomes after posterior interbody fusion. This series suggests that consideration of sagittal balance during posterior interbody fusion for degenerative spondylolisthesis can yield high levels of patient satisfaction and restore spinal balance Methods: A retrospective study of clinical outcomes and a radiological review was performed on 18 patients with one or two level degenerative spondylolisthesis. Patients were divided into two groups: the patients without improvement in pelvic tilt, postoperatively (Group A; n = 10) and the patients with improvement in pelvic tilt postoperatively (Group B; n = 8). Pre- and postoperative clinical outcome surveys were administered to determine Visual Analogue Pain Scores (VAS) and Oswestry disability index (ODI). In addition, we evaluated full spine radiographic films for pelvic tilt (PT), sacral slope (SS), pelvic incidence (PI), thoracic kyphosis (TK), lumbar lordosis (LL), sacrofemoral distance (SFD), and sacro C7 plumb line distance (SC7D) Results: All 18 patients underwent surgery principally for the relief of radicular leg pain and back pain. In groups A and B, mean preoperative VAS were 6.85 and 6.81, respectively, and these improved to 3.20 and 1.63 at last follow-up. Mean preoperative ODI were 43.2 and 50.4, respectively, and these improved to 23.6 and 18.9 at last follow-up. In spinopelvic parameters, no significant difference was found between preoperative and follow up variables except PT in Group A. However, significant difference was found between the preoperative and follows up values of PT, SS, TK, LL, and SFD/SC7D in Group B. Between parameters of group A and B, there is borderline significance on preoperative PT, preoperative LL and last follow up SS. Correlation analysis revealed the VAS improvements in Group A were significantly related to postoperative lumbar lordosis (Pearson's coefficient = -0.829; p = 0.003). Similarly, ODI improvements were also associated with postoperative lumbar lordosis (Pearson's coefficient = -0.700; p = 0.024). However, in Group B, VAS and ODI improvements were not found to be related to postoperative lumbar lordosis and to spinopelvic parameters. Conclusion: In the current series, patients improving PT after fusion were found to achieve good clinical outcomes in degenerative spondylolisthesis. Overall, our findings show that it is important to quantify sagittal spinopelvic parameters and promote sagittal balance when performing lumbar fusion for degenerative spondylolisthesis.

We sought to determine the surgical treatment and functional outcome and identify the predictors of survival in a retrospective cohort of patients with spinal cord ependymoma using data collected from the Korea Spinal Oncology Research Group database. The data regarding 88 patients who had been surgically treated for histologically confirmed spinal cord intramedullary and extramedullary ependymoma from January 1989 to December 2009 were retrospectively reviewed. Histopathological examination revealed myxopapillary ependymoma in 24 patients, ependymoma in 61 patients, and anaplastic ependymoma in 3 patients. Gross total removal was achieved in 72 patients, subtotal removal in 15 patients, and partial removal in 1 patient. Twenty patients were treated with postoperative radiation. Fifty-two patients had stable or improved postoperative neurological function, while 36 experienced neurological deterioration. A permanent decrease in McCormick classification grade was seen in 17 patients. The progression-free survival rate was 87% for all patients at 5 years and 80% at 10 years. During follow-up, local recurrence/progression was seen in 13 patients. Diffuse meningeal spread developed in 2 anaplastic ependymoma patients. Postoperative radiotherapy after incomplete resection did not significantly correlate with longer times to recurrence. Multivariate analysis revealed histology and surgical extent of resection as independent predictors of longer progression-free survival. Gross total removal alone is a good treatment strategy for spinal ependymomas. Early diagnosis and surgery, before severe paralysis, are important to obtain good functional outcomes. Subtotal resection with radiation therapy for intramedullary lesions appears to offer no advantages over gross total removal.

Objective We compare the surgical results of single-stage posterior surgical procedure performed at a single institute with those of anterior procedure, and propose single-stage posterior surgical approach, laminectomy and posterior decompression with transpedicular instrumentation as an alternative operative method for thoracic and thoracolumbar spinal tuberculosis. Methods From January 2001 to December 2004, 10 patients (group 1) who had less bone destruction or poor medical condition were treated with posterior decompression and transpedicular instrumentation that was supplemented with posterolateral bone fusion and chemotherapy. Seven patients (group 2) who had greater bone destruction were treated with anterior decompression, bone fusion, and anterior instrumentation. Except one case who expired, all patients were followed up for average 18 months (6 mo to 3.5 y). Results Spinal tuberculosis was completely cured and the grafted bones were fused in all 16 patients. The visual analog scale and Frankel grade improved in all cases. There was no persistence or recurrence of infection possibly related to the instrumentation. There were no differences in the radiological results in both groups. The kyphosis was significantly corrected after surgical management. However, the loss of correction also occurred considerably in both groups. Conclusions The posterior decompression with transpedicular instrumentation can be an alternative treatment method of less-involved spinal tuberculosis especially for patients in early phase of bone destruction or ones with mild kyphosis.

Piezo channels are mechanosensitive ion channels. Piezo1 is primarily expressed in nonsensory tissues, whereas Piezo2 is predominantly found in sensory tissues, including dorsal root ganglion (DRG) neurons. However, a recent study demonstrated the intracellular calcium response to Yoda1, a selective Piezo1 agonist, in trigeminal ganglion (TG) neurons. Herein, we investigate the expression of Piezo1 mRNA and protein in mouse and human DRG neurons and the activation of Piezo1 via calcium influx by Yoda1. Yoda1 induces inward currents mainly in small- (<25 μm) and medium-sized (25–35 μm) mouse DRG neurons. The Yoda1-induced Ca²⁺ response is inhibited by cationic channel blocker, ruthenium red and cationic mechanosensitive channel blocker, GsMTx4. To confirm the specific inhibition of Piezo1, we performed an adeno-associated virus serotype 2/5 (AAV2/5)-mediated delivery of short hairpin RNA (shRNA) into mouse DRG neurons. AAV2/5 transfection downregulates piezo1 mRNA expression and reduces Ca²⁺ response by Yoda1. Piezo1 also shows physiological functions with transient receptor potential vanilloid 1 (TRPV1) in the same DRG neurons and is regulated by the activation of TRPV1 in mouse DRG sensory neurons. Overall, we found that Piezo1 has physiological functions in DRG neurons and that TRPV1 activation inhibits an inward current induced by Yoda1.