Autophagy in an extruded disc compared to the remaining disc after lumbar disc herniation in the same patient.

PURPOSE: The purpose of this study was to investigate autophagy in an extruded disc and to compare this activity with the activity in the remaining disc after lumbar disc herniation in the same patient. METHODS: In total, 12 patients (females 4, males 8) with the extruded type of lumbar disc herniation (LDH) were surgically treated. Their mean age was 54.3 ± 15.8 years (range: 29 ~ 78 years). The mean interval from the occurrence of symptoms to the operation was 9.8 ± 9.4 weeks (range: 2 ~ 24 weeks). The extruded discs were excised, and the remaining disc material removed, to prevent recurrence of herniation. Immediately after specimen collection, all tissues were stored at -70 °C prior to analysis. Autophagy was assessed immunohistochemically and via Western blotting for Atg5, Atg7, Atg12, Atg12L1, and Beclin-1. And the relationship between autophagy and apoptosis was investigated by correlation analysis of caspase-3 with autophagy proteins. RESULTS: The expression levels of autophagic markers were significantly increased in the extruded discs compared to the remaining discs within the same patients. The mean expression levels of Atg5, Atg7, Atg12, and Beclin-1 in extruded discs were statistically significantly higher than those in the remaining discs (P < 0.01, P < 0.001, P < 0.01, and P < 0.001 respectively). CONCLUSIONS: The autophagic pathway was more active in extruded disc material than in remaining disc material within the same patient. This may explain spontaneous resorption of the extruded disc after LDH.

Analysis of Fracture Patterns and Characteristics in Sacral Insufficiency Fracture: Do Sacral Fractures Occur in Patients Who Had Previous Lumbosacral Fusion Insufficiency Fractures or Stress Fractures?

STUDY DESIGN: This study is a retrospective analysis of a case. PURPOSE: The purpose of this study is to investigate the fracture patterns and risk factors of sacral insufficiency fractures (SIFs) to improve their diagnosis in clinical practice. OVERVIEW OF LITERATURE: SIFs occur when normal stresses are applied to a bone with decreased density, most often due to osteoporosis. Individuals who receive lumbosacral fusion procedures may also suffer from increased incidents of SIFs because of decreased bone density related to aging. METHODS: In total, 55 patients with SIFs were retrospectively investigated in this study. The study population was divided into lumbosacral fusion (n=20) and non-fusion (n=35) groups. Subsequently, the patients' demographic characteristics, comorbidities, medication history, results of diagnostic imaging studies, and bone mineral density were assessed. The fracture patterns were classified either according to the five typical types (H-pattern bilateral vertical plus horizontal component, unilateral vertical only, bilateral vertical only, unilateral vertical plus horizontal component, and horizontal only fracture) or atypical types. RESULTS: In total, 44 of 55 patients (80%) suffered from more than one senile disease and received corresponding medications that caused secondary osteoporosis. A total of 12 patients had S1 lumbosacral fixation. Moreover, three of these 12 patients who developed a SIF immediately after a lumbosacral fracture had an unstable sacral U fracture. The remaining nine patients showed fracture patterns similar to the non-fusion patients. Single-photon emission computed tomography (SPECT)/computed tomography (CT) can identify fracture recurrence in previously healed fractures. In total, 24 patients (43.6%) had fractures of the pelvis, femur, and thoracolumbar spine. CONCLUSIONS: SIF develops in elderly patients with multiple adult diseases that can induce secondary osteoporosis. Such fractures may occur in the patients with instrumented lumbosacral fusion. Importantly, some patients showed stress fractures after multilevel instrumented lumbosacral fusion, whereas others showed insufficiency fractures. The different fracture patterns correspond to different grades of SIF, and SPECT/CT can easily identify the fracture status.

Comparison of Union Rates Between Autogenous Iliac Crest Bone Graft and Local Bone Graft as Fusion Materials in Lumbar Fusion Surgery: An Evaluation of Up to 3-Level Fusion.

OBJECTIVE: To compare the radiologic union rates between autogenous iliac crest bone graft (ICBG) and local bone graft in 1- to 3-level lumbar fusion. METHODS: We reviewed 178 consecutive patients who underwent 1- to 3-level lumbar fusion surgery because of lumbar spinal stenosis. Fusion status of the anterior or posterior column was evaluated by plain radiographs obtained at 24 months postoperatively. If at least either the anterior or posterior column was fused, that segment was regarded as having achieved fusion and was termed segment union. The definition of overall union was achieving union of all segments in a single patient. RESULTS: For each ICBG group and local bone graft group, fusion rate of the anterior and posterior column, and rate of the segments and overall union at postoperative 2 years were not different between the groups, regardless of surgery level. In the overall union rate according to the fusion level, the ICBG group showed constant overall fusion rate according to the fusion level (i.e., 96.9%, 96.9%, and 93.1% for 1-, 2-, and 3-level fusion), but tended to decrease with increasing level in the local bone graft group (100%, 95.8%, and 85.7% for 1-, 2-, and 3-level fusion, respectively) without statistically significant differences. CONCLUSIONS: The union rate of 3-level fusion was not inferior to those of 1- or 2-level fusion in both ICBG and local bone graft patients. Local bone graft could be regarded as an adequate option for not only 1- or 2-level lumbar fusion but also 3-level lumbar fusion surgery.

Minimally Invasive Lateral Lumbar Interbody Fusion for Clinical Adjacent Segment Pathology: A Comparative Study With Conventional Posterior Lumbar Interbody Fusion.

STUDY DESIGN: This was a retrospective comparative study. OBJECTIVE: The main objective of this article was to evaluate the clinical and radiologic efficacies of minimally invasive lateral lumbar interbody fusion (LLIF) for clinical adjacent segment pathology (ASP). SUMMARY OF BACKGROUND DATA: Minimally invasive techniques have been increasingly applied for spinal surgery. No report has compared LLIF with conventional posterior lumbar interbody fusion for clinical ASP. METHODS: Forty patients undergoing LLIF with posterior fusion (hybrid surgery) were compared with 40 patients undergoing conventional posterior lumbar interbody fusion (posterior surgery). The radiologic outcomes including indirect decompression in hybrid surgery group, and clinical outcomes such as the Oswestry Disability Index (ODI) and Visual Analog Scale (VAS) were assessed. Postoperative major complications and reoperations were also compared between the 2 groups. RESULTS: Correction of coronal Cobb's angle and segmental lordosis in the hybrid surgery were significantly greater postoperatively (2.8 vs. 0.9 degrees, P=0.012; 7.4 vs. 2.5 degrees, P=0.009) and at the last follow-up (2.4 vs. 0.5 degrees, P=0.026; 4.8 vs. 0.8 degrees, P=0.016) compared with posterior surgery. As regards indirect decompression of the LLIF, significant increases in thecal sac (83.4 vs. 113.8 mm) and foraminal height (17.8 vs. 20.9 mm) were noted on postoperative magnetic resonance imaging. Although postoperative back VAS (4.1 vs. 5.6, P=0.011) and ODI (48.9% vs. 59.6%, P=0.007) were significantly better in hybrid surgery, clinical outcomes at the last follow-up were similar. Moreover, intraoperative endplate fractures developed in 17.7% and lower leg symptoms occurred in 30.0% of patients undergoing hybrid surgery. CONCLUSIONS: Hybrid surgery for clinical ASP has advantages of segmental coronal and sagittal correction, and indirect decompression compared with conventional posterior surgery. However, LLIF-related complications such as endplate fracture and lower leg symptoms also developed. LLIF should be performed considering advantages and approach-related complications for the clinical ASP.

Clinical and Radiographic Features of Subtypes of Acute Proximal Junctional Failures Following Correction Surgery for Degenerative Sagittal Imbalance.

OBJECTIVE: To identify clinical and radiographic features of subtypes of acute proximal junctional failures (PJFs) following correction surgery for degenerative sagittal imbalance. METHODS: The study included 157 patients with mean age 68.0 ± 6.3 years who underwent correction surgery for degenerative sagittal imbalance. Acute PJFs were categorized into 4 subtypes: fracture at uppermost instrumented vertebra (UIV), fracture at vertebra just proximal to UIV (UIV+1), fixation failure at UIV, and junctional subluxation. Demographic, clinical, and radiographic data were analyzed retrospectively. RESULTS: There were 18 patients with acute PJFs. PJF group had significantly lower T-score (-3.3 ± 1.1 vs. -1.9 ± 1.5) on bone densitometry and lower body mass index (BMI) (23.0 ± 3.9 kg/m2 vs. 25.6 ± 3.7 kg/m2) than non-PJF group. Radiographic parameters exhibited no significant differences. UIV fracture, UIV+1 fracture, UIV fixation failure, and junctional subluxation were observed in 5, 6, 4, and 3 patients. Fixation failure developed the earliest (median 1.3 months), followed by UIV fracture (1.5 months). UIV fracture occurred earlier than UIV+1 fracture (36 months). Patients with UIV or UIV+1 fracture had significantly lower T-scores than others. Although BMI and T-score were significant risk factors for all PJFs (P = 0.043 and P = 0.021, respectively), different risk factors for each subtype of PJFs were identified on separate risk factor analysis. CONCLUSIONS: Patients with acute PJFs had lower T-score and BMI. Each subtype of PJFs had different clinical and radiographic features. Although BMI and T-score were associated with all PJFs, each subtype may have different risk factors. Identifying risk factors for each subtype of acute PJFs may help avoid it.

Clinical Significance of Preoperative Embolization for Non-Hypervascular Metastatic Spine Tumors.

OBJECTIVE: The efficacy of preoperative embolization for hypervascular metastatic spine disease (MSD) such as renal cell and thyroid cancers has been reported. However, the debate on the efficacy of preoperative embolization for non-hypervascular MSD still remains unsettled. The purpose of this study is to determine whether preoperative embolization for non-hypervascular MSD decreases perioperative blood loss. METHODS: A total of 79 patients (36 cases of preoperative embolization and 43 cases of non-embolization) who underwent surgery for metastatic spine lesions were included. Representative hypervascular tumors such as renal cell and thyroid cancers were excluded. Intraoperative and perioperative estimated blood losses (EBL), total number of transfusion and calibrated EBL were recorded in the embolization and non-embolization groups. The differences in EBL were also compared along with the type of surgery. In addition, the incidence of Adamkiewicz artery and complications of embolization were assessed. RESULTS: The average age of 50 males and 29 females was 57.6±13.5 years. Lung (30), hepatocellular (14), gastrointestinal (nine) and others (26) were the primary cancers. The demographic data was not significantly different between the embolization and the non-embolization groups. There were no significant differences in intraoperative EBL, perioperative EBL, total transfusion and calibrated EBL between two groups. However, intraoperative EBL and total transfusion in patients with preoperative embolization were significantly lower than in non-embolization in the corpectomy group (1645.5 vs. 892.6 mL, p=0.017 for intraoperative EBL and 6.1 vs. 3.9, p=0.018 for number of transfusion). In addition, the presence of Adamkiewicz artery at the index level was noted in two patients. Disruption of this major feeder artery resulted in significant changes in intraoperative neuromonitoring. CONCLUSION: Preoperative embolization for non-hypervascular MSD did not reduce perioperative blood loss. However, the embolization significantly reduced intraoperative bleeding and total transfusion in corpectomy group. Moreover, the procedure provided insights into the anatomy of tumor and spinal cord vasculature.

Pure distraction injury of T1-2 with quad fever.

INTRODUCTION: We report a pure distraction injury of the upper thoracic spine and uncontrolled hyperthermia without an infectious cause. Quad fever appears in the first several weeks to months after a cervical or upper thoracic SCI and is characterized by an extreme elevation in body core temperature beyond 40 °C without an infectious cause. Discriminating between infectious and noninfectious causes is important, and a thorough clinical assessment is required. MATERIALS AND METHODS: A 52-year-old male visited the emergency room complaining of back pain with complete paralysis [American Spinal Injury Association (ASIA) A] of both lower extremities after a pedestrian-motor vehicle accident. He had trouble breathing due to a hemothorax and flail chest caused by fractures of the right second to eleventh and left fourth to seventh ribs. A computed tomography scan revealed severe distraction of the T1-2 intervertebral space. A magnetic resonance image showed signal changes in the spinal cord and a clean-cut margin between the T1-2 disc and T2 body. The neurological level of injury was C8 upon the initial neurological assessment. Emergency surgery was performed. C6-T3 posterior instrumentation and an autologous iliac bone graft were performed. RESULTS: After surgery, the core temperature increased gradually to above 38.0 °C on post-trauma day 4 and increased to 40.8 °C on post-trauma day 7. None of the repeated aerobic, anaerobic, or fungal cultures of the blood, tracheal aspirate, line tips, urine, or stool was positive until post-trauma day 21, when Candida tropicalis was identified in the urine culture. On post-trauma day 63, the blood pressure, pulse, and body temperature stabilized and the patient was transferred to the general ward. At post-trauma year 6, the injury state was still complete and the neurological level of injury was changed to C4. CONCLUSIONS: Based on the Grand Round case and relevant literature, we discuss the case of pure distraction injury of T1-2 with quad fever. Spinal surgeons should be knowledgeable regarding quad fever as well as the differential diagnoses and treatment strategies.

Bone Mineral Density and Osteoporotic Vertebral Fractures in Traditional, Unassisted, Free-Diving Women (Haenyeos).

BACKGROUND: Water pressure and muscle contraction may influence bone mineral density (BMD) in a positive way. However, divers experience weightlessness, which has a negative effect on BMD. The present study investigated BMD difference in normal controls and woman free-divers with vertebral fracture and with no fracture. METHODS: Between January 2010 and December 2014, traditional woman divers (known as Haenyeo in Korean), and non-diving women were investigated. The study population was divided into osteoporotic vertebral fracture and non-fracture groups. The BMD of the lumbar spine and femoral neck was measured. The radiological parameters for global spinal sagittal balance were measured. RESULTS: Thirty free-diving women and thirty-three non-diving women were enrolled in this study. The mean age of the divers was 72.1 ± 4.7 years and that of the controls was 72.7 ± 4.0 years (P = 0.61). There was no statistical difference in BMD between the divers and controls. In divers, cervical lordosis and pelvic tilt were significantly increased in the fracture subgroup compared to the non-fracture subgroup (P = 0.028 and P = 0.008, respectively). Sagittal vertical axis was statistically significantly correlated with cervical lordosis (Spearman's rho R = 0.41, P = 0.03), and pelvic tilt (Spearman's rho R = 0.46, P = 0.01) in divers. CONCLUSION: BMD did not differ significantly between divers and controls during their postmenopausal period. When osteoporotic spinal fractures develop, compensation mechanisms, such as increased cervical lordosis and pelvic tilt, was more evident in traditional woman divers. This may be due to the superior back muscle strength and spinal mobility of this group of women.

Clinical and Radiologic Features of Osteoporotic Spine Fracture with Delayed Neurologic Compromises.

OBJECTIVES: Osteoporotic spine fractures (OSFs) with delayed neurologic compromises (NCs) have been increasingly reported. Although several studies have addressed that the pathologic mechanism of NC involves nonunion and segmental instability, the risk factors remain unclear. Therefore, the purpose of this study was to assess the radiologic and clinical features of OSFs with delayed NC. METHODS: Thirty patients with delayed NC (group 1) were matched in a 1-to-1 format with 30 patients without delayed NC (group 2) by age, bone mineral density, body mass index, and medical treatment for osteoporosis. Clinical and radiologic parameters were assessed to determine the risk factors related to delayed NC. Clinical outcomes were also compared between the 2 groups. RESULTS: Neurologic compromises were presented as myelopathy in 20 patients and radiculopathy in 10 patients. Initial kyphotic angle (KA) and height loss (HL) were significantly greater in group 1 (21.6 ± 12.9 degrees vs. 10.5 ± 8.6 degrees, P = 0.0001 for KA; 55.8% ± 15.2% vs. 19.9% ± 10.9%, P = 0.0001 for HL). Fracture instability with intravertebral cleft, posterior wall involvement, midportion type of magnetic resonance classification, thoracolumbar level, and aortic calcification were significantly correlated with delayed NC. In multivariate analysis, initial HL (hazard ratio = 1.24; P = 0.012) and midportion-type fracture (hazard ratio = 14.9: P = 0.03) were the independent risk factors related to delayed NC. In addition, clinical outcomes at the last follow-up were significantly better in group 2. CONCLUSIONS: Initial HL and midportion-type fracture were correlated with delayed NC following OSFs. Moreover, pre-existing stenotic lesions might be associated with delayed NC.

Delayed bilateral facet dislocation at L4-5: A case report.

RATIONALE: Traumatic bilateral facet dislocation in the lumbar (L) spine has rarely been reported. All reported cases were presented with acute facet dislocation. However, we present the first case of delayed bilateral facet dislocation at L4-5. PATIENT CONCERNS: A 34-year-old woman presented with back pain after a head-on collision. The patient was treated conservatively for 3 months with rigid orthosis and activity restriction. Even after this conservative treatment, she continued to suffer from persistent back pain that radiated down her left leg and a progressively kyphotic posture. DIAGNOSES: Initial imaging studies revealed a fracture of the left L5 superior articular process with a posterior ligament complex (PLC) injury. Subsequent radiographs showed the locked facet dislocation with kyphotic changes. INTERVENTIONS: The patient underwent surgical reduction and fusion, and the operative findings revealed the L4-5 bilateral facet dislocation and rupture of the PLC at the index level. OUTCOMES: After surgical reduction and fusion at L4-5 by posterior interbody fusion, we achieved a satisfactory clinical outcome. LESSONS: Injury of the PLC in the lower lumbar region deserves careful attention for the development of sequelae. The anatomic transition from lordosis to kyphosis, in the lumbosacral region may be related to this type of injury.

Clinical importance of posterior vertebral height loss on plain radiography when conservatively treating osteoporotic vertebral fractures.

PURPOSE: To predict spinal canal compromise, the assessment of plain radiography with magnetic resonance imaging (MRI) can aid the detection of vertebral body collapse and prevent the development of neurological deficits. METHODS: Patients who suffered osteoporotic vertebral fractures (OVFs) between January 2012 and December 2014 underwent consecutive radiological assessments, including measurements of anterior height loss (AHL), posterior height loss (PHL), and the kyphotic angle (KA). The fracture morphology was classified by AOSpine thoracolumbar spine injury classification system. MRI was performed at the initial assessment and the extent of canal encroachment (CE) was calculated in all patients. Follow-up computed tomography (CT) or MRI was performed in patients exhibiting significant height loss in follow-up radiography. The fracture patterns in T1- and T2-weighted MRI were also assessed. RESULTS: A total of 485 patients visited our institute for treatment of OVFs and 97 were enrolled; 15 were male and 82 were female. The mean age at initial visit was 70.3±14.6years. The initial spinal CE was correlated with the initial PHL and the initial AHL. The follow-up CE was correlated with age, the initial PHL, and the difference between the initial and last PHL (ΔPHL(initial-last)). OVFs with both endplate fractures have a greater tendency of posterior wall collapse than those with single endplate fracture. On initial T1-weighted sagittal MRI, a diffuse low signal change pattern of the fractured vertebra was correlated with PHL. Delayed neurological deficits developed in four patients. These patients underwent surgical intervention. CONCLUSIONS: In patients with simple compression fractures, attention should be paid to the posterior vertebral body and both endplates as well as the T1-weighted MRI findings to allow early detection of spinal canal compromise, which can have devastating consequences.

Foreign Body Reaction after Implantation of a Device for Intervertebral Assisted Motion.

The device for intervertebral assisted motion (DIAM) is a dynamic implant that consists of a silicone bumper enveloped by a polyethylene terephthalate (PET) fiber sack. Silicone and PET were used because of their biological inertness, but repetitive motion of the spine can cause wear on the implant nonetheless. The purpose of this study is to report a case of foreign body reaction (FBR) against a DIAM. A 72-year-old female patient presented with lower back pain and both legs radiating pain. She had undergone DIAM implantation at L4-5 for spinal stenosis 5 years previously. The intervertebral disc space of L4-5, where the DIAM was inserted, had collapsed and degenerative scoliosis had developed due to left-side collapse. MRI showed L3-4 thecal sac compression and left L4-5 foraminal stenosis. The patient underwent removal of the DIAM and instrumented fusion from L3 to L5. During surgery, fluid and granulation tissue were evident around the DIAM. Histopathology showed scattered wear debris from the DIAM causing chronic inflammation due to the resulting FBR. A FBR due to wear debris of a DIAM can induce a hypersensitivity reaction and bone resorption around the implant, causing it to loosen.

Three-dimensional analysis of volumetric changes in herniated discs of the lumbar spine: does spontaneous resorption of herniated discs always occur?

PURPOSE: To investigate volumetric changes in lumbar disc herniation (LDH) using three-dimensional measurements obtained by magnetic resonance imaging (MRI) and to identify possible factors affecting such changes. METHODS: Between January 2004 and December 2011, 43 patients who underwent conservative treatment for LDH were enrolled. In all, 56 disc levels were investigated. MRI was performed on two or more occasions (minimally, at the initial visit and 6 months later). The volume of each herniated disc was determined. For each patient, disc migration, morphology, initial LDH size, and clinical outcome were evaluated. RESULTS: The mean volumes of herniated discs at the initial and follow-up visits were 1,304.57 ± 837.99 and 993.84 ± 610.04 mm(3), respectively. The mean change in volume from the initial to the follow-up visit was 310.73 ± 743.60 mm(3). Volumes decreased at 35 disc levels and increased at 21 levels. The disc containment, the extent of LDH, the initial size of the herniated disc, and the degree of intactness of the posterior longitudinal ligament were significantly correlated with disc resorption and an increase in disc volume (p = 0.01, p = 0.018, p = 0.001, and p < 0.001, respectively). No significant association was evident between disc volumetric change and clinical outcome. CONCLUSIONS: We observed that LDH is a dynamic disease and that a herniated disc is not always spontaneously resorbed, in contrast to what has been reported previously. Alleviation of clinical symptoms can be achieved via conservative treatment even if the volume of the herniated disc changes. Spinal surgeons should not only present an option of initial non-surgical treatment to LDH patients but should also inform them that the LDH may change in size during daily activity or exercise.

Effects of Therapeutic Hypothermia on Apoptosis and Autophagy After Spinal Cord Injury in Rats.

STUDY DESIGN: Animal study. OBJECTIVE: To further investigate the effects of therapeutic hypothermia (TH), the present study compared autophagy and apoptosis after treatment with either therapeutic moderate systemic hypothermia or methylprednisolone sodium succinate (MP) in a rat model of acute spinal cord injury (SCI). SUMMARY OF BACKGROUND DATA: The neuroprotective effects of TH have recently become an important topic in the field of SCI research. METHODS: All rats were subjected to a 25-g/cm spinal cord contusion over the ninth thoracic vertebrae. After the induction of SCI, the control group did not receive any further treatment, TH group immediately received moderate systemic hypothermia for 4 hours, and MP group was administered high-dose MP. The rats were killed either 2 or 7 days after SCI, and the injured spinal cord tissues were obtained. Apoptosis and autophagy were assessed by immunohistochemical analyses and Western blot analyses. In addition, the microarchitecture of the autophagosomes was evaluated using transmission electron microscopy, and the motor activity of the rats was assessed using the Basso-Beattie-Bresnahan (BBB) locomotor rating scale. RESULTS: Compared with controls, there was a significant reduction in the expression levels of cleaved caspase-8, -9, and -3 in the TH- and MP-treated groups 2 days after SCI. Moreover, compared with the control group, the expression of LC3II and Beclin-1 exhibited a significant decrease on day 2 after treatment with TH. The numbers of transferase dUTP nicked-end labeling and LC3-positive cells were significantly lower on days 2 and 7. The Basso-Beattie-Bresnahan ratings were significantly higher 6 weeks after SCI in both the TH- and MP-treated groups than in the control group. CONCLUSION: Both TH and MP have neuroprotective effects on injured spinal cord tissues via the inhibition of apoptosis and autophagy. Thus, the application of moderate systemic hypothermia may be a useful treatment modality after acute SCI. LEVEL OF EVIDENCE: N/A.

Bone cement augmentation procedures for spinal pathologic fractures by multiple myeloma.

Efficacy and safety of bone cement augmentations for spinal pathologic fractures related to multiple myeloma, and usefulness of radionuclide studies for surgical decision were retrospectively evaluated. Forty eight vertebrae from 27 patients for bone cement augmentation procedures and 48 vertebrae from 29 patients for conservative treatment were enrolled. Clinical results using visual analogue scale (VAS) and Oswestry disability index (ODI), and radiologic results were assessed. For clinical decisions on treatment of spinal pathologic fracture, bone scan or single photon emission computed tomography was done for 20 patients who underwent surgery. Mean follow-up was 16.8 months. In terms of clinical results, immediate pain relief was superior in the operated group to that in the conservative group. ODI, maintenance of vertebral height and local kyphotic angle at the last follow-up were superior in the operated group in comparison to the conservative group. At one year follow-up, cumulative survival rate were 77.4% and 74.7% in the operated and conservative groups, respectively (log rank test> 0.05). Leakage of bone cement was noted at 10 treated vertebrae. Bone cement augmentations presented short-term pain relief for spinal pathologic fractures by myeloma with relative safety in highly selected patients, and radionuclide imaging studies were useful for the surgical decision on these procedures.

Does extracorporeal shock wave introduce alteration of microenvironment in cell therapy for chronic spinal cord injury?

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. LEVEL OF EVIDENCE: N/A.

Spinal cord compression by B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma in a patient seropositive for human immunodeficiency virus: a case report.

INTRODUCTION: Although non-Hodgkin's lymphoma is one of the most common and frequently fatal of the acquired immune deficiency syndrome-defining illnesses, survival has improved significantly since the introduction of antiretroviral therapy. Patients with spinal cord compression resulting from non-Hodgkin's lymphoma present with clinically acute or rapidly progressive neurologic deficits. The purpose of this case report is to present a case of a patient seropositive for human immunodeficiency virus with spinal cord compression due to B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma. CASE PRESENTATION: A 40-year-old Asian man, who was seropositive for human immunodeficiency virus, presented with progressive neurological deficits. Magnetic resonance images of his thoracic spine showed an epidural mass from T2 to T4, resulting in severe cord compression. Emergent surgical decompression and biopsy were performed, followed by palliative radiation therapy. The pathologic findings showed that the specimen was compatible with B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma. Palliative radiation therapy was performed; however, leptomeningeal seeding and pulmonary embolism led to his death. CONCLUSIONS: When a patient infected with human immunodeficiency virus presents with a rapidly progressive spinal tumor accompanying paraplegia, non-Hodgkin's lymphoma should be considered, and surgical decompression should be weighed with respect to the patient's general condition and the subtype/prognosis of the lymphoma.

Distal femoral cortical proliferative irregularity with excavation in a 6-year-old girl.

The distal femur is a common site for benign or malignant bone tumors in children or adolescents. Distal femoral cortical irregularities at the posterior aspect of the distal femoral metaphysis must be differentiated from malignant bone tumors because they might be misinterpreted as malignant neoplasm. Plain radiographs of a 6-year-old girl complaining of left knee pain for 4 weeks showed cortical proliferation with excavation on her distal femoral metaphysis. Computed tomography, magnetic resonance imaging and bone scan helped to differentiate the cortical irregularity from malignant lesions. Therefore unnecessary invasive surgery was avoided in this patient.

Percutaneous vertebroplasty for cephalad vertebral fractures after instrumented lumbar fusion.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To identify the effect of cement augmentation for cephalad vertebral fracture after instrumented lumbar fusion. SUMMARY OF BACKGROUND DATA: Osteoporosis may contribute to cephalad vertebral fractures by an altered biomechanics in the adjacent segments due to the loss of motion at the fused segments. However, few studies on the treatment for cephalad fractures using bone cement augmentation after instrumented lumbar fusion have been published. METHODS: Seventeen patients who had cephalad vertebral fractures after instrumented lumbar fusion underwent percutaneous vertebroplasty (PVP). All patients were divided into 2 groups according to the presence of intravertebral vacuum clefts (IVC) on plain radiographs and magnetic resonance imaging: group 1 consisted of 9 patients without an associated IVC and group 2 consisted of 8 patients with an IVC. The Oswestry Disability Index and the Visual Analogue Scale were recorded prospectively. The radiologic parameters of kyphotic deformity, vertebral height changes, and leakage of cement were studied. RESULTS: The Oswestry Disability Index and Visual Analogue Scale scores in group 1 decreased after PVP, but the mean score in group 2 was higher than in group 1 at the last follow-up. The mean kyphosis measured 15.7±7.4 degrees preoperatively and 15.6±7.1 degrees at the final follow-up in group 1, and 16.9±8.8 degrees preoperatively and 27.2±8.8 degrees at the final follow-up in group 2.The mean preoperative anterior and posterior vertebral height ratio measured 0.6±0.2 preoperatively and 0.6±0.2 at the final follow-up in group 1, and 0.6±0.2 preoperatively and 0.5±0.2 at the final follow-up in group 2.The mean preoperative middle and posterior vertebral height ratio measured 0.5±0.1 preoperatively and 0.6±0.1 at the final follow-up in group 1, and 0.5±0.1 preoperatively and 0.4±0.2 at the final follow-up in group 2. Four patients underwent revision surgery in group 2 and 1 in group 1. CONCLUSIONS: Although PVP treatment may be a useful method for cephalad vertebral fractures after instrumented lumbar fusion in elderly patients with persistent unremitting back pain, recollapse of the vertebral body can occur after a PVP for cephalad or adjacent vertebral fractures with an IVC.

Percutaneous posterior instrumentation followed by direct lateral interbody fusion for lumbar infectious spondylitis.

STUDY DESIGN: Retrospective study. OBJECTIVES: To investigate the clinical feasibility and outcomes from direct lateral interbody fusion (DLIF) using autogenous bone grafts and percutaneous posterior instrumentation (PPI) for infectious spondylitis. SUMMARY OF BACKGROUND DATA: As one of the minimally invasive techniques, PPI has been attempted for various degenerative lumbar spine disorders combined with anterior lumbar interbody fusion or transforaminal lumbar interbody fusion. PPI has been played more roles recently as an internal fixation method for infectious spondylitis. However, the clinical outcomes of DLIF using an autogenous bone graft combined with PPI for infectious spondylitis have been rarely reported. MATERIALS AND METHODS: Sixteen patients (mean age, 60.3 ± 18.8 y) who suffered from pyogenic spondylitis underwent single-stage DLIF using an autogenous iliac bone graft combined with PPI. Clinical and radiologic outcomes were evaluated by visual analog scale (VAS), Oswestry Disability Index (ODI), and eradication of primary disease. Radiologic outcomes were evaluated by changes of affected segmental lordosis and fusion status. RESULTS: Bony fusion and eradication of primary disease were obtained in all patient except 1 case during the follow-up (mean, 31.3 ± 13.1 mo; range 14-46 mo). Preoperative VAS (7 ± 1.2) and ODI (61.3 ± 5.4) scores improved significantly at the last follow-up (VAS, 3.4 ± 1.5; ODI, 32.3 ± 15.4). C-reactive protein normalized at postoperative 20.1 ± 0.7 days (range, 15-28 d). Although height and lordosis in the affected segment were restored by surgery, all patients showed loss of the restored lordosis and height at the final follow-up. Loss of the restored lordosis and height were related to subsidence of the grafted bone. CONCLUSIONS: Minimally invasive PPI followed by debridement and DLIF was a feasible surgical alternative in our consecutive 16 cases of pyogenic spondylitis. In most cases, however the subsidence of anteriorly grafted fusion was inevitable despite successful fusion and eradication of the primary lesion.