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Study Design: A retrospective cohort study.Objective: To evaluate the clinical and radiological efficacies of supplementing minimally invasive lateral lumbar interbody fusion (LLIF) with open posterior spinal fusion (PSF) in adult spinal deformity (ASD).Summary Of Background Data: Minimally invasive techniques have been increasingly applied for surgery of ASD. Few reports have been published that directly compare LLIF combined with PSF to conventional PSF for ASD.Methods: To evaluate the advantages of minimally invasive LLIF for ASD, patients who underwent minimally invasive LLIF followed by open PSF (combined group) were compared with patients who only underwent PSF (only PSF group). The clinical and radiological outcomes for deformity correction and indirect decompression were assessed. The occurrence of proximal junctional kyphosis (PJK) and proximal junctional failure (PJF) were also evaluated.Results: No significant differences were observed in the clinical outcomes of the Oswestry Disability Index (ODI), visual analog scale, and major complications including reoperations between the groups. No additional advantage was found for coronal deformity correction, but the restoration of lumbar lordosis in the combined group was significantly higher postoperatively (15.3° vs. 8.87°, P = 0.003) and last follow-up (6.69° vs. 1.02°, P = 0.029) compared to that of the only PSF group. In the subgroup analysis for indirect decompression for the combined group, a significant increase of canal area (104 vs. 122 mm) and foraminal height (16.2 vs. 18.5 mm) was noted. The occurrence of PJK or PJF was significantly higher in the combined group than in the only PSF group (P = 0.039).Conclusion: LLIF has advantages of indirect decompression and greater improvements of sagittal correction compared to only posterior surgery. LLIF should be conducted considering the above-mentioned benefits and complications including PJK or PJF in ASD.Level Of Evidence: 4. [ABSTRACT FROM AUTHOR]

Study Design: Animal experimental study OBJECTIVES.: The purpose of this study is to investigate the effects of extracorporeal shock waves (ESWs) on endogenous neural stem cells (NSCs) proliferation after spinal cord injury (SCI).Summary Of Background Data: Exogenous stem cell transplantation for SCI still has many limitations to be addressed such as ideal cell sources, timing of transplantation, and fate of the transplanted cells. Moreover, the efficacy is another issue owing to a peculiar pathologic condition in the chronic phase of SCI.Methods: Contusive SCI was made using 24 Sprague-Dawley rats, and ESWs were applied at post-injury 4 weeks in rats. Proliferation and differentiation of endogenous NSCs (DCX, Sox-2) and axonal sprouting (GAP-43 and MAP-2) were observed at 6 weeks after application of ESWs. Differentiation of the activated neural stem cells was also investigated by coexpression of neuronal/glial cell markers (GFAP, Neu N, and CC-1). Immunofluorescence staining and western blotting were performed for quantitative analysis, and these results were compared with those in the control group. For clinical assessment, the BBB locomotor rating scale was performed.Results: More proliferation of endogenous neural stem cells was noted in the experimental groups, and these activated cells were mainly founded in the ependymal layer of the central canal and the injured posterior horn. Differentiation into neuronal and glial cells was also noted in a limited number of cells. With respect to axonal regeneration, GAP-43 and MAP-2 expressions in the experimental groups were also significantly higher than those in the control group. During 6 weeks' clinical observation following ESWs application, functional improvement of the hindlimb was observed without clinical deterioration by trials.Conclusion: Collectively, these findings indicate that ESWs on the chronic phase of SCI induce activation of endogenous NSCs and consequent functional improvement.Level Of Evidence: N/A. [ABSTRACT FROM AUTHOR]

Study Design: Retrospective cohort study. Objective: The aim of this study was to evaluate the clinical relevance of the SRS-Schwab classification for degenerative lumbar scoliosis (DLS). Summary Of Background Data: The SRS-Schwab classification has been presented and validated as a useful tool for adult spinal deformity (ASD). This classification includes various types of ASD (degenerative de novo scoliosis or adult form of idiopathic scoliosis). However, DLS has different clinical characteristics and pathophysiology compared with other forms of ASD. Methods: In this retrospective cohort study, 216 (146 conservatively treated and 70 surgically treated) DLS patients were enrolled. The average patient age was 72.1 ± 7.4 years. Clinical parameters for disability were measured using Oswestry disability index (ODI) and back and leg pain numerical rating scale. Radiographic parameters included SRS-Schwab sagittal modifiers (pelvic tilt [PT]; sagittal vertical axis [SVA];pelvic incidence-lumbar lordosis [PI-LL]), T1 pelvic angle, and coronal parameters (Cobb's angle [CA]; coronal imbalance [CI]; coronal deviation distance [CDD]; tilting angle [TA]). Correlations between clinical parameters and radiographic parameters were assessed and surgical rates along the SRS-Schwab sagittal modifiers were evaluated. Results: Only PI-LL as a sagittal radiographic parameter showed a weak correlation with clinical parameters (r = 0.137-0.176) (P < 0.05). Coronal parameters such as CA, CI, CDD, and TA also showed weak correlation with clinical parameters (r = 0.137-0.202) (P < 0.05). Multiple regression analysis identified CA, CI, CDD, and PI-LL to be correlated with clinical parameters. On analysis for clinical outcomes (surgical rates and patient self-reported disability) along the grades of the SRS-Schwab sagittal modifiers, PT and SVA were not related to higher surgical rates or disability. Conclusion: Even though some radiological parameters showed statistically significant results, correlation between radiological and clinical parameters was weak. Not only deformity but also other clinical factors should be considered when evaluating DLS. Level Of Evidence: 4. [ABSTRACT FROM AUTHOR]

Study Design. Animal experimental study. Objective. To present experimental evidence for cell therapy for spinal cord injury (SCI). Summary of Background Data. In chronic SCI, the efficacy of cell engraftment has been known to be low due to its distinct pathology. Alteration of microenvironment was tried using extracorporeal shock waves (ESW) for chronic SCI, and the efficacy of cell therapy was investigated. Methods. A chronic contusive SCI model was made in 36 Sprague-Dawley rats. The rats were allocated into (1) control group (SCI only), (2) ESW control group (SCI + ESW), (3) IV group (SCI + intravenous transplantation of mesenchymal stem cells; MSCs), and (4) ESW + IV group (SCI + MSCs IV transplantation after ESW). ESW were applied at the energy determined by our preliminary trials. Engraftment of the cells and expressions of growth factors (brain-derived neurotrophic factor, neuronal growth factor) and cytokines (SDF-1, CXCR4, VEGF) at the epicenter were assessed. The Basso, Beattie, and Bresnahan locomotor scale was used for the clinical assessment. Results. The mean numbers of engrafted cells were higher in the ESW+ IV than that in the IV with a statistical significance. The expression of SDF-1 was higher in the ESW groups than that in the control or IV group. CXCR4 was highly expressed in the transplanted groups. The expressions of growth factors in the treated group were higher in the treated group than those in the control group. However, various statistical significances were noted. The improvement of locomotor was higher in the transplanted groups than that in the control and ESW only group. Conclusion. At a given energy level, ESW presented more engraftment of the transplanted MSCs without any clinical deterioration in a chronic SCI. Based on this promising result and possible explanations, ESW may cause an alteration of the microenvironment for the cell therapy in chronic SCI. [ABSTRACT FROM AUTHOR]

Study Design. A retrospective comparative study. Objective. To investigate adjacent segment pathology (ASP) after limited lumbar fusion in the treatment of degenerative lumbar scoliosis (DLS). Summary of Background Data. The assessment of appropriate surgical techniques for DLS remains one of the most controversial topics in spinal surgery. So far, there has been no study specifically addressing why ASP shouts different patterns with respect to different fusion levels after instrumented lumbar fusion for DLS. Methods. Fifty-nine patients were enrolled and divided into 2 groups with respect to the proximal fusion level: group I consisted of 29 patients who underwent fusion below the proximal neutral vertebrae, and group II consisted of 30 patients who underwent fusion to the proximal neutral vertebrae. Clinical and radiological assessments were performed with an average of 59.4 months of follow-up. The number of radiological findings for ASP was determined on the basis of a 7-point scale that gave 1 point for each radiological finding. The 2 groups were analyzed according to radiological ASP (RASP). The Oswestry Disability Index and visual analogue scale scores were recorded prospectively. Results. Overall, RASP developed in 16 (27.1 %) patients. In group I, 12 (41.4%) of 29 patients, and in group II, 4 (13.3%) of 30 patients showed RASP. Group I yielded an average of 4.5 points, and group II, 1.8 points. RASP scores were much higher in group I than in group II, with statistical significance (P = 0.000). In group 1, 4 patients underwent revision surgery, but in group II, only 1 patient did so. Conclusion. RASP displayed variance according to different fusion levels. RASP in group I showed similar patterns to the natural progression of DLS. It is suggested that fusion be included at least at the proximal neutral vertebrae to reduce RASP although RASP with different patterns is unavoidable. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the fate of posterior osteophytes following anterior cervical discectomy and fusion (ACDF) using computed tomography. Information on the advantage of the ACDF method is provided. Results of the study showed that posterior osteophytes decreased in 23% of patients and increased in 16%. No significant changes were observed in the mean anteroposterior diameter of each intervertebral foramen of fused segments postoperatively.

The article presents a study that examined both sequestrated nucleus pulposus (SNP) and the remaining nucleus pulposus (RNP) from the discs of the same patient. The study evaluated apoptosis using immunohistochemical staining. It compared apoptosis of the SNP and the RNP in the disc of the same patient.

The article discusses the clinical association between bone graft volumetric changes and lumbar fusion. The study aims to determine patterns of bone graft volumetric changes and factors that affect these changes. After patients with lumbosacral disease have undergone decompression and instrumented spinal fusion, it was found that one-third of the initial one grafts were resorbed over 5 years and larger bone grafts resulted to a larger fusion mass.

The article reports on a study which investigates the neuroprotective effect of moderate epidural hypothermia (MEH) after spinal cord injury in rats. The study showed that MEH significantly reduced the apoptosis of neurons and glial cells when compared with the control group. It also showed that MEH suppressed the activation of the microglia and improved functional recovery after spinal cord injury.

The article presents a study about the degeneration of sacroiliac joint following an instrumented lumbar or lumbosacral fusion. This study focuses on the cause-effect relationship of fusion and sacroiliac joint degeneration after an instrumented posterolateral lumbar or lumbosacral fusion. A cohort study was conducted with 37 patients.

The article presents a study which demonstrates the apoptotic effect of oxidative stress and the antiapoptotic effects of caspase inhibitors on rat notochordal cells. Researchers have exposed cultured rat notochordal cells to oxidative stress and evaluated the activations of caspases and the cleavages of Bid and poly polymerase. Results suggest that inhibition of premature oxidative stress-induced apoptosis of notochordal cells may delay the starting point of disc degeneration.

The article presents a clinical study that aims to evaluate the results of anterior strut grafting and the loss of the reduction in anterior interbody fusion and anterior interbody fusion combined with posterior instrumental fusion in pyogenic spondylodiscitis. Reduction of intervertebral height and of sagittal profile occurred in both groups due to destruction of the endplate by surgical debridement or infective process. Despite loss of correction, both groups had high fusion rates.

STUDY DESIGN.: Immunohistochemistry was performed in organ-cultured intact and cartilage endplate (CE)-fractured rat intervertebral discs (IVDs). OBJECTIVES.: To demonstrate biologic events associated with migration of chondrocytes from hyaline CE into nucleus pulposus (NP). SUMMARY OF BACKGROUND DATA.: It was recently revealed that the transition from a notochordal NP to a fibrocartilaginous NP in the rabbit IVD is accomplished exogenously by chondrocytes migrating from CEs into the NP. This observation has not been studied in other animal models, and the biologic events associated with chondrocyte migration have not been elucidated in the literature. METHODS.: IVDs including cranial and caudal CEs were obtained from 4-week, 6-month, 12-month, and 18-month old Wistar rats. To accelerate chondrocyte migration, CEs of IVDs were fractured and cultured for 48 hours. IVDs without CE-fracture were used as a control for each age group. Expressions of membrane-type I matrix metalloproteinase (MT1-MMP, as a marker for cell migration and extracellular matrix digestion) and Ki-67 protein (as a proliferation marker) and pericellular deposition of type II collagen (as a marker for fibrocartilaginous matrix) by the chondrocytes migrating from CE into NP were examined immunohistochemically. RESULTS.: In the control groups, chondrocyte migration limited only along the periphery of the notochordal NP and no chondrocytes were inside the NP proper. However, all the IVDs in the CE-fracture groups showed direct and more extensive migration of chondrocytes from CEs into the NP proper. The migrating chondrocytes in both control and CE-fracture groups expressed MT1-MMP and Ki-67 protein and deposited type II collagen in the NP. CONCLUSIONS.: This report demonstrates the chondrocyte migration from CE into NP in the organ-cultured rat IVDs. This phenomenon is accelerated in the presence of CE fracture. The chondrocytes migrating from CEs into the NP expressed MT1-MMP and Ki-67 protein and deposited type II collagen. These biologic strategies probably enable chondrocytes of the hyaline CE to migrate into the ectopic NP region, replace notochordal cells, and change the notochordal tissue into fibrocartilage. These results suggest that similar biologic mechanisms may be involved in the natural transition from the notochordal NP to the fibrocartilaginous NP in other animal models, including human. [ABSTRACT FROM AUTHOR]

STUDY DESIGN.: Immunohistochemical study was done by harvesting articular cartilage of the facet joints during the decompressive surgery for spinal stenosis.OBJECTIVES.: To observe the expression of estrogen receptor on the articular cartilage of the facet joints in degenerative spondylolisthesis (DS)SUMMARY OF BACKGROUND DATA.: Few attempts have been made to evaluate the effect of sex-hormone, although DS is more common in females than in males.METHODS.: After harvesting the articular cartilage of the facet joints in 17 DS and in 15 spinal stenosis (SS) patients, the expression of estrogen receptor and the severity of facet arthritis were observed by H-E and immunohistochemical staining, respectively. Measurements of both staining were made by using a semiquantitative analysis.RESULTS.: The significantly increased expression of estrogen receptor correlated with the severity of facet arthritis (r = 0.78, P < 0.05). There was a significantly increased expression of estrogen receptor of the facet joint in DS compared with SS (P < 0.01). The histologic-histochemical grading of cartilage lesion in DS was 12.4 (SEM, 0.6), which was significantly higher than in SS (P < 0.05).CONCLUSIONS.: These findings suggest that the higher expression of estrogen receptor might aggravate degenerative change of the facet articular cartilage and might also be considered one of the causative factors for DS in postmenopausal women. [ABSTRACT FROM AUTHOR]

STUDY DESIGN.: Bacterial adherence and biofilm formation in implant-associated infection may vary depending on species of microorganisms and characteristics of implant surfaces. OBJECTIVES.: We evaluated the differences in adherence and biofilm formation between Staphylococcus epidermidis and Mycobacterium tuberculosis on various spinal implant surfaces. SUMMARY OF BACKGROUND DATA.: In implant-associated infections, bacteria in biofilm are resistant to antibiotics or host defense mechanism. The removal of implants is usually necessary to eradicate infection. On the contrary, in tuberculous infection, complete debridement and antituberculous chemotherapy without removal of implant have been regarded as a safe procedure. METHODS.: S. epidermidis and M. tuberculosis were cultured with 4 types of metal segments, smooth or rough-surfaced stainless steel, and titanium alloy, respectively. After isolation of colonized microorganisms and biofilm with trypsin treatment and culture on plate media, colony-forming units were counted. The features of adherence and biofilm formation were observed under scanning electron microscopy. RESULTS.: Biofilm-forming S. epidermidis showed heavy adhesion and multiplication on the surface of all 4 metal segments, 16.5 times more colony-forming units than nonbiofilm-forming ones. On scanning electron microscopy, there were many aggregated microcolonies with thick biofilm in biofilm-forming S. epidermidis but much less in nonbiofilm-forming S. epidermidis. M. tuberculosis were rarely adhered to metal surfaces and showed scanty biofilm formation. CONCLUSIONS.: On the contrary to S. epidermidis, adherence and biofilm formation of M. tuberculosis on implant surface are less likely, and it can provide the basis of successful instrumentation in spine tuberculosis. [ABSTRACT FROM AUTHOR]

STUDY DESIGNA case report and review of the literature.OBJECTIVESTo present a case of chronic inflammatory epidural granuloma formed after acupuncture.SUMMARY OF THE BACKGROUND DATAA number of cases of complications resulting from acupuncture have been reported, including acute infection, hemorrhage, and direct injury to internal organs or neural tissues. However, to the best of our knowledge, there has been no report of epidural granuloma formed following acupuncture and mimicking clinical manifestations of lumbar stenosis.METHODSA 68-year-old woman suffered from low back pain and sciatica aggravated by acupuncture. We reviewed her medical record, imaging studies, microscopic findings of the mass, and related literature.RESULTSMicroscopic examination revealed the mass as a chronic inflammatory granuloma. From her previous history and imaging study, the mass, which compressed the lumbar forth nerve and dural sac ,was highly suspected to have been formed after acupuncture. Surgical decompression and excision of the epidural mass relieved her symptoms.CONCLUSIONChronic inflammatory granuloma may be formed as a complication of acupuncture. Under such circumstances, surgical excision of the mass may be an effective way of relieving the symptoms. [ABSTRACT FROM AUTHOR]

STUDY DESIGNA case of bilateral pedicle stress fracture is reported, and the literature is reviewed.OBJECTIVESTo report the rare case of bilateral pedicle stress fracture after instrumented posterolateral fusion, and to investigate the contributing factors.SUMMARY OF BACKGROUND DATAA 62-year-old man underwent revision spinal surgery for adjacent-segment degeneration. Decompression and instrumented posterolateral fusion from L1 to L3 were performed after removal of the previously inserted pedicular screws. In the patient's history, he had undergone L3-L5 instrumented posterolateral fusion for spinal stenosis 6 years previously. At 1 year after the revision surgery, he presented with severe progressive low back pain. Computer-assisted tomogram and bone scan demonstrated bilateral L4 pedicle stress fracture. To the best of the authors' knowledge, only two cases of pedicle stress fracture after lumbar posterolateral fusion have been reported.METHODSThis study reviewed the reported patient's medical record, his imaging studies, and related literature. The possible factors contributing to bilateral pedicle stress fractures were investigated.RESULTSIn the reported case, the features of radiographic studies confirmed bilateral pedicle stress fracture. The involved vertebra was L4. In all three cases reported so far, including the current case, the site of the pedicle stress fracture was at the junction of the pedicle and vertebral bodies.CONCLUSIONSBilateral pedicle stress fracture occurs as a complication of posterolateral lumbar fusion. Pedicle weakening by prior inserted screws and persistent anterior motion after posterolateral fusion are the contributing factors. [ABSTRACT FROM AUTHOR]

STUDY DESIGNA case report and review of the literature are presented.OBJECTIVETo describe an unusual simple bone cyst involving the pedicle of lumbar spine.SUMMARY OF BACKGROUND DATATo the authors' knowledge, only nine cases of a simple bone cyst involving the spine have been reported. Most of these reports have described mild back or neck pain because the presenting symptoms or cysts were found incidentally. In the reported case, acute severe back pain with radiating pain developed. Therefore, the study focus was on the unusual location, the presenting symptoms, and its spinal involvement.METHODSA cystic lesion involving the left pedicle of the first lumber vertebra was identified in a 53-year-old woman with sudden-onset severe back pain with pain radiating to the left leg. Surgical resection was undertaken along with review of the patient's medical record, imaging studies, microscopic findings of the lesion, and the related literature.RESULTSMicroscopic examination of the cystic lesion corresponded with the findings of a simple bone cyst. A thin fibrous membrane with reactive bone formation was identified without evidence of hemorrhage. A favorable result was achieved by surgical resection.CONCLUSIONSThis case study suggests that a simple bone cyst may be found in any portion of the spine, including the pedicle. Severe resting pain would be elicited by a pathologic fracture of the pedicle. Direct nerve compression by the fractured fragment and chemical irritation by cystic fluid would be compatible with the observed clinical manifestations. [ABSTRACT FROM AUTHOR]