Traumatic Anterior Cervical Disc Herniation Presenting as Severe Dysphagia.

Due to the anatomical characteristics of the cervical spine, few cases of traumatic anterior cervical disc herniation have been reported in the literature. Here, we present a rare case of a traumatic anterior cervical disc herniation presenting as severe dysphagia. A 75-year-old male patient presented with severe dysphagia following an accident three days prior when he fell from a height of stairs. Cervical magnetic resonance (MR) imaging revealed a 1.3 × 1.0 cm extruded disc in the anterior aspect of the C4 level with the base at the C3-4 disc, which displaced the esophagus anteriorly. Esophagography revealed an extrinsic esophageal lesion that was considered to be responsible for the obstruction of the airway at the same level. He underwent a ruptured disc removal via the anterior approach. Preoperative dysphagia was resolved gradually after surgery, and he remained asymptomatic six months after surgery.

Massive Epidural Hematoma Caused by Percutaneous Epidural Neuroplasty: A Case Report.

Percutaneous epidural neuroplasty (PEN) has been used to manage chronic back pain or radicular pain refractory to other conservative treatments, such as medication, injection, and physical therapy. However, similar to all invasive treatment modalities, it has serious complications, such as dural tears, infections, and hematoma formation. Herein, we present a rare case of an 81-year-old female patient on dementia medication who developed paraplegia 5 days after PEN. This is the first report of a poor outcome in a patient with dementia who developed paraplegia after PEN despite an emergency operation for spinal epidural hematoma.

Acute Paraparesis Caused by Spinal Epidural Fluid After Balloon Kyphoplasty for Traumatic Avascular Necrosis: A Case Report.

Minimally invasive procedures, such as percutaneous vertebroplasty or balloon kyphoplasty (BK), eliminate motion at the fracture site and relieve pain associated with traumatic avascular necrosis when conservative treatment fails. However, these are associated with complications, most of which are directly related to cement leakage. Herein, we report a rare case of acute paraparesis caused by spinal cord compression by epidural fluid following BK for the treatment of Kummell's disease in the absence of cement leakage. To the best of our knowledge, this is the first report describing this complication.

Open Surgery for Osteoporotic Compression Fracture Within One Month of Single Level Balloon Kyphoplasty.

Objective: This study aimed to analyze the reasons for open surgery performed within one month of balloon kyphoplasty (BKP) for osteoporotic compression fractures. Methods: This study included 15 patients treated with open surgery within one month of BKP in our institution from 2013 to 2020. Among them, 10 patients underwent BKP in our institution and 5 patients were transferred because of adverse events after undergoing BKP at another hospital. Clinical findings including main indications, neurological deficits, and clinical course were analyzed. Results: All patients were followed up for at least 12 months after surgery (average time 15.5 months, range 12-39 months). Their mean age was 73.7 years and the mean T-score of the spine on bone densitometry was -3.35. The main reasons for open surgery included dislodgement of the cement mass or spinal instability (7 cases, 47%), neural injury due to cement leakage (3 cases, 20%), and spinal cord injury caused by a puncture mistake (3 cases, 20%). Two patients developed acute spinal subdural hematoma, and spinal epidural fluid was pushed out at the back edge of the vertebral body following BKP without signs of major cement leakage into the spinal canal. At the final follow-up, 7 patients with cement mass dislodgement showed complete improvement of related symptoms after posterior fusion with screw fixation. Among the 8 patients with neural injury, 6 improved; however, 2 remained at the same American Spinal Injury Association level. Conclusion: The main reasons for open surgery were cement mass dislodgement and neural injury caused by puncture errors or cement leakage into the spinal canal. It should be noted that proper selection of cases, detailed imaging evaluation, and optimal surgical techniques are key to reducing open surgery after BKP.

Risk Factors of Restenosis After Full Endoscopic Foraminotomy for Lumbar Foraminal Stenosis: Case-Control Study.

OBJECTIVE: To investigate risk factors associated with postoperative restenosis after full endoscopic lumbar foraminotomy (FELF) in patients with lumbar foraminal stenosis (LFS). METHODS: A single-center, retrospective case-control study was conducted on patients diagnosed with foraminal stenosis who underwent FELF between August 2019 and April 2022. The study included 56 patients, comprising 18 cases and 38 controls. Clinical data, radiologic assessments, and surgical types were compared between the groups. The cutoff values of radiologic parameters that differentiate the 2 groups were investigated. RESULTS: No significant difference in age, sex distribution, or presence of adjacent segment disease or grade I spondylolisthesis was observed between the groups. Cases had a higher degree of disc wedging angle (DWA) (3.0° ± 1.1° vs. 0.5° ± 1.4°, p < 0.001), larger coronal Cobb angle (CCA) (8.8° ± 5.1° vs. 4.7° ± 2.5°, p = 0.004), and smaller segmental lumbar lordosis (SLL) than controls (11.0 ± 7.4 vs. 18.0 ± 5.4, p = 0.001). Optimal cutoff values for DWA, CCA, and SLL were estimated as 1.8°, 7.9°, and 17.1°, respectively. A significant difference in surgical types was observed between cases and controls (p = 0.004), with the case group having a higher distribution of patients undergoing discectomy in addition to TELF. CONCLUSION: The study identified potential risk factors for restenosis after FELF in patients with LFS, including higher DWA, larger CCA, smaller SLL angle. We believe that discectomy should be perform with caution during FELF, as it can lead to subsequent restenosis.

Complications of Cervical Endoscopic Spinal Surgery: A Systematic Review and Narrative Analysis.

BACKGROUND: There are no systematic evidence-based medical data on the complications of endoscopic cervical spinal surgery. This narrative analysis compiled data from various studies that examined endoscopic complications, such as cervical disc herniation and foraminal stenosis. This study aimed to investigate the efficacy and safety of endoscopic surgery in cervical radiculopathy. METHODS: We searched the PubMed/MEDLINE databases to identify articles on endoscopic spinal surgery, and keywords were set as "endoscopic cervical spinal surgery", "endoscopic cervical discectomy", "endoscopic cervical foraminotomy", and "percutaneous endoscopic cervical discectomy". We analyzed the evidence level and classified the prescribed complications according to the literature. Endoscopic cervical surgery was divided into three categories: full endoscopic anterior, endoscopic posterior, and unilateral biportal approaches. We excluded duplicate publications, studies without full text, studies without complications or incomplete information, and studies that did not provide the necessary data for extraction, animal experiments, or reviews. RESULTS: Difficulties in swallowing, hematoma, and hoarseness are common complications associated with the anterior cervical approach. In contrast, complications of the posterior approach include nerve root injury, hematoma, and dysesthesia. However, endoscopic cervical spinal surgery, including the full endoscopic anterior, posterior, and unilateral biportal approaches, is a safe and effective treatment for cervical radiculopathy. CONCLUSIONS: Complications of full endoscopic cervical spinal surgery differ significantly depending on the anterior and posterior approaches. In the anterior approach, swallowing difficulty, recurrent disc, hematoma, and dysphonia are the common complications. In contrast, transient dysesthesia, dural tears, upper limb motor deficits, and persistent arm pain are commonly reported with the posterior approach.

Complications and Management of Endoscopic Spinal Surgery.

In the past, the use of endoscopic spine surgery was limited to intervertebral discectomy; however, it has recently become possible to treat various spinal degenerative diseases, such as spinal stenosis and foraminal stenosis, and the treatment range has also expanded from the lumbar spine to the cervical and thoracic regions. However, as endoscopic spine surgery develops and its indications widen, more diverse and advanced surgical techniques are being introduced, and the complications of endoscopic spine surgery are also increasing accordingly. We searched the PubMed/MEDLINE databases to identify articles on endoscopic spinal surgery, and key words were set as "endoscopic spinal surgery," "endoscopic cervical foramoinotomy," "PECD," "percutaneous transforaminal discectomy," "percutaneous endoscopic interlaminar discectomy," "PELD," "PETD," "PEID," "YESS" and "TESSYS." We analyzed the evidence level and classified the prescribed complications according to the literature. Endoscopic lumbar surgery was divided into full endoscopic interlaminar and transforaminal approaches and a unilateral biportal approach. We performed a comprehensive review of available literature on complications of endoscopic spinal surgery. This study particularly focused on the prevention of complications. Regardless of the surgical methods, the most common complications related to endoscopic spinal surgery include dural tears and perioperative hematoma. transient dysesthesia, nerve root injury and recurrence. However, Endoscopic spinal surgery, including full endoscopic transforaminal and interlaminar and unilateral biportal approaches, is a safe and effective a treatment for lumbar as well as cervical and thoracic spinal diseases such as disc herniation, lumbar spinal stenosis, foraminal stenosis and recurrent disc herniation.

Contraindications and Complications of Full Endoscopic Lumbar Decompression for Lumbar Spinal Stenosis: A Systematic Review.

OBJECTIVE: The purpose of this study was to suggest appropriate indications and contraindications for full endoscopic surgery and to predict the prognosis for the incidence of complications by reviewing the literature on full endoscopic lumbar decompression for various spinal stenoses and systematically analyzing the contraindications and complications of endoscopic surgery. METHODS: We searched the PubMed/MEDLINE database to identify articles on full endoscopic decompression for lumbar spinal stenosis. The levels of evidence in all studies were classified according to the method adopted by the North American Spine Society (NASS) 2005. Full endoscopic lumbar decompression was divided into interlaminar and transforaminal decompressions. We selected articles that contained preoperative contraindications and complications during and after surgery. We analyzed the evidence level and classified the prescribed contraindications and complications according to the literature. RESULTS: We identified 362 articles, of which 57 met our criteria, with evidence ranging from levels I to V. After reviewing the literature on full endoscopic lumbar decompression, pure back pain without neurogenic symptoms and instability/deformities requiring stabilization were found to be contraindications. Also, in transforaminal decompression, central stenosis or complex foraminal stenoses were contraindications. Dysesthesia (most common), untreated pain, dural tear, disc herniation, infection, incomplete decompression, and other complications have been reported as complications of transforaminal decompression. On the other hand, dural tear (most common), epidural hematoma, transient dysesthesia, untreated pain, motor weakness, and other complications have been reported in interlaminar decompression. CONCLUSIONS: Full endoscopic lumbar surgery, including transforaminal and interlaminar decompression, is a safe and effective surgical option for treating lumbar spinal stenosis; however, it is important to select the transforaminal or interlaminar approach according to the indication.

Tracheostomy Following Anterior Cervical Discectomy and Fusion With Plating in Trauma Patients: Is It Safe?

Objective: This study aimed to evaluate the safety and necessity of tracheostomy after anterior cervical discectomy and fusion (ACDF) with plating, despite the close proximity of the two surgical skin incisions. Methods: Sixty-three patients with traumatic cervical fractures or spinal cord injury (SCI) who underwent single-level ACDF and plating between January 2014 and June 2019 were included in this study. The patients included 45 men and 18 women, with a mean age of 48.5 years. A retrospective analysis of the patients' demographic data, level of injury, radiological findings, and neurological status was performed based on the American Spinal Injury Association (ASIA), open tracheostomy, and decannulation rate. Additionally, risk factors necessitating tracheostomy were statistically analyzed. Results: Eighteen patients (28.5%) required subsequent open tracheostomy. Among them, 11 patients were successfully decannulated, four patients could not be decannulated during the follow-up period, and three patients died of unrelated complications. The median interval from ACDF with plating to open tracheostomy was 9.6 days (range, 5-23 days). On the basis of neurological status, ASIA A and B patients (p<0.001), high signal intensity on T2-weighted-magnetic resonance (MR) images (p=0.001), and major cervical fracture and dislocation were significant risk factors for tracheostomy (p=0.02). No patient showed evidence of significant soft tissue, bony infection, or nonunion during the follow-up period. Conclusion: Independent tracheostomy did not increase the risk of infection or nonunion despite the close proximity of the two surgical skin incisions.

Pyogenic Andersson Lesion in a Patient With Ankylosing Spondylitis.

Although the exact etiology of the Andersson lesion (AL) remains unclear, it is known to occur mostly in patients with long-standing ankylosing spondylitis (AS). Among the various theories for the etiology of AL, repetitive trauma and inflammatory causes are the most common. The histopathological appearance of the AL in this report was consistent with that of chronic inflammation without any infection. Pyogenic ALs in the context of AS are extremely rare; to the best of our knowledge, positive cultures of this lesion in bone biopsies have never been reported. Herein, we report a rare case of a pyogenic AL with a positive culture and discuss a relevant review of the literature.

Anterior Approaches for Two-Level Cervical Degenerative Disease: A Comparative Study of at least 6-Year Follow-Up.

OBJECTIVE: To compare the clinical and radiogrincaphic results of a hybrid surgery (HS) and cervical artificial disc replacement (ADR) for contiguous two-level cervical spondylosis. METHODS: A total of 56 patients with contiguous two-level degenerative cervical spondylosis who underwent cervical HS and ADR via an anterior approach and completed at least 6 years of follow-up were included in this study. Patients were divided into two groups: group I, comprising 22 patients who underwent ADR, and group II, comprising 34 patients who underwent HS combined ADR and anterior cervical discectomy and fusion using a cage. Clinical outcomes were evaluated based on the visual analog scale (VAS) scores for arm pain, neck disability index (NDI), and modified MacNab criteria. Radiological parameters were assessed by measuring the bone fusion status, cervical range of motion (ROM C2-C7), heterotopic ossification (HO), adjacent segment disease (ASD) incidence, and fused segment height (FSH). RESULTS: The VAS scores and NDI significantly improved in both groups, without significant differences between the groups. The incidences of HO, ROM C2-C7, and FSH were similar between groups, without significant differences. New osteophyte formation and osteophyte enlargement at adjacent segments were more frequently found in the HS group; however, the difference was not significant. CONCLUSION: Clinical results of this study showed that the clinical efficacy and radiological changes in HS were similar to those of ADR. HS can be an alternative procedure for the treatment of two-level cervical spondylosis.

Treatment of Extensive Spinal Epidural Abscess with Skipped Laminotomy Using a Pediatric Feeding Tube: A Case Report.

Spinal epidural abscess (SEA) is an unusual form of spinal infection. Performing multilevel laminectomies is controversial in cases of extensive SEA considering the long surgical time and mechanical instability. Here, we report the case of an older woman with extensive SEA and poor general condition who was successfully treated with a less invasive treatment, namely skipped laminotomy using a pediatric feeding tube. A 79-year-old woman complained of progressive weakness in both legs, fever, and back pain. An extensive epidural abscess from the T3 to L5 vertebrae was observed on thoracic and lumbar magnetic resonance imaging (MRI). We performed skipped laminotomy at the T8 and T12 levels, and a 5-Fr pediatric feeding tube was advanced from the caudal level toward the rostral area and rostral level toward caudal level into the dorsal epidural space. Subsequently, regurgitation was performed with saline through the pediatric feeding tube at each level. Following this, to further irrigate the unexposed epidural abscess through laminotomy, the epidural space was washed by continuous irrigation, and the irrigation system was maintained for 48 hours. Follow-up MRI performed 3 weeks after the procedure confirmed near complete removal of the abscess in the thoracic spine, with a small residual abscess in the lumbar spine.

Efficacy of Antibiotic-Loaded Cement Augmentation for Correcting Low Grade Pedicle Screw Loosening.

OBJECTIVE: Altered biomechanics and bone fragility can contribute to pedicle screw loosening. This study aimed to evaluate the efficacy of antibiotic-loaded cement augmentation for correcting symptomatic screw loosening as a minimally invasive alternative to open revision surgery. METHODS: Ten consecutive patients who underwent percutaneous cement augmentation for pedicle screw loosening were included in this study. Low grade pedicle screw loosening was deemed clinically relevant in cases of continuous back pain with significant radiolucent halo zones at a vertebral level without screw backing out or stripping. We analyzed the screw loosening at the main location of halo formation. All patients were treated by fluoroscopy-guided antibiotic-loaded cement augmentation of the loosened pedicle screws. Patient demographics and pre- and postoperative data were also assembled and analyzed. RESULTS: Most (80%) halo formation locations were the inferior type. Augmentation was technically feasible in all but one patient, in whom the procedure was unsuccessful due to access difficulty. This patient ultimately underwent percutaneous screw re-implantation via a different trajectory. The other nine patients in whom cement filling was satisfactory reported significant pain relief at the final follow-up. Moreover, no severe complications such as wound infection or repeated screw loosening occurred during the follow-up period. CONCLUSION: The most common halo formation location was the inferior type. In cases without access difficulty, antibiotic-loaded cement augmentation for the treatment of low grade pedicle screw loosening can relieve pain and avoid extensive open surgery.

Technical Considerations of the Transforaminal Approach for Lumbar Disk Herniation.

Transforaminal full endoscopic lumbar diskectomy (TELD) is a typical minimally invasive surgery, with the associated benefit of decreased possibility of anatomic structural injury, and is an effective alternative to open diskectomy. Among the various endoscopic spinal surgical techniques currently available, TELD is the most basic and traditional surgery that can be performed through the transforaminal route; it has been used for >30 years. Recently, with the advancements in surgical techniques, TELD has been successfully performed for patients with lumbar disk herniation of different types. However, beginner surgeons are unfamiliar with the anatomy of transforaminal endoscopic surgery and this surgery has a steep learning curve to date. If not well prepared, operators may experience complications that require reoperation in the early stages. These complications may include symptomatic incomplete decompression, exiting nerve root injury, dural tearing, and rarely, hematoma, infection, and visceral injury. Here, we propose several technical guidelines for TELD to increase the possibility of successful lumbar diskectomy and to reduce the incidence of complications. The first step is the accurate anatomic understanding of Kambin triangle and determining the appropriate endoscopic access angle, depending on the type of disk herniation. The second step is to determine a safe and easily accessible entry point and then landing and docking the working sleeve as close to the target as possible without causing exiting nerve root injury. The third step is complete decompression of the symptomatic nerve with free mobilization of the neural tissue. The final step involves performing foraminoplasty using an advanced technique to overcome the limitations associated with TELD in difficult cases.

Extradural Spinal Arachnoid Cyst as a Cause of Cauda Equina Syndrome in a Child.

Although spinal arachnoid cysts are relatively common findings observed incidentally in adults, they are much rarely reported in children. They are usually asymptomatic and are mainly located in the middle and lower thoracic regions. However, in rare circumstances, these cysts can cause mass effects that lead to neurologic symptoms. We report the rare case of a spinal extradural arachnoid cyst in a 12-year-old boy who showed signs and symptoms of cauda equina syndrome. Magnetic resonance imaging of the lumbar spine revealed a huge extradural arachnoid cyst extending from L2 to L5. Emergent laminectomy and repair of dural defect was performed after total resection of the extradural arachnoid cyst. There were no postoperative complications. Total recovery was achieved 6 months after surgery. Here, we report this rare case with a review of the literature.

Anterior Approach Following Intraoperative Reduction for Cervical Facet Fracture and Dislocation.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of the anterior approach following intraoperative reduction under general anesthesia in patients with cervical facet fracture and dislocation. METHODS: Twenty-three patients with single level cervical facet fracture and dislocation who were subjected to the anterior approach alone following immediate intraoperative reduction under general anesthesia from March 2013 to December 2017 were enrolled in this study. Neurological status, clinical outcome, and radiological studies were evaluated preoperatively, postoperatively, and during the follow-up period. RESULTS: The cohort comprised 15 men and eight women with a mean age of 57 years (from 24 to 81). All patients were operated on within the first 8 hours following the injury. After gentle manual reduction or closed reduction with Gardner-Wells traction, under general anesthesia monitored by somatosensory-evoked potentials, all operations were successfully completed using the anterior approach alone except in two patients, who had a risk of over-distraction. In them, a satisfactory gentle manual reduction or closed reduction was not possible, and required open posterior reduction of the locked facets followed by anterior cervical discectomy and fusion. In one patient, screw retropulsion was observed in 1 month after surgery. There were no reduction-related complications or neurological aggravations after surgery. All patients showed evidence of stability at the instrumented level at the final follow-up (mean follow-up, 12 months). CONCLUSION: Anterior approach following intraoperative reduction monitored by somatosensory-evoked potentials under general anesthesia for cervical dislocation and locked facets is a relatively safe and effective alternative when cervical alignment is achieved by intraoperative reduction.

Predictive Scoring and Risk Factors of Early Recurrence after Percutaneous Endoscopic Lumbar Discectomy.

PURPOSE: To predict the early recurrence after full endoscopic lumbar discectomy, we analyzed factors related to demographic factor anatomical factors, operative method, and postoperative management, and predicted the possibility of recurrence according to the scoring system. MATERIALS AND METHODS: In this prospective study, we enrolled 300 patients who underwent 1 out of 3 surgical procedures. The patients were randomized into one of the following groups: group A (n = 100), transforaminal inside-out approach; group B (n = 100), transforaminal outside-in approach; and group C (n = 100), interlaminar approach. The clinical results were evaluated by a visual analogue scale (VAS). Related factors evaluated with points of (A) demographic factors: (1) age, (2) gender, (3) BMI, (B) anatomical factors: (4) disc degeneration scale, (5) modic change, (6) number of involved disc herniation, (7) history of discectomy (first, recurred), (8) herniated disc level, (9) disc height, (10) segmental dynamic motion, (11) disc location, (C) operation factors: (12) annulus preservation along the disc protrusion, (13) approach method (transforaminal inside-out, transforaminal outside-in, interlaminar); (D) postoperative care factors: (14) early ambulation, (15) spinal orthosis (corset) application. Among these, we analyzed statistically significant recurrence risk factors after PELD in all patients and early recurrence predicting score ratio was obtained. RESULTS: The overall recurrence rate was 9.33%. The recurrence rate was 11%, 10%, and 7% for groups A, B, and C, respectively. Average early recurrence time was 3.26 months. The change in preoperative and postoperative VAS score was from 8.07 to 1.39, 8.34 to 1.34, and 8.14 to 1.86 in groups A, B, and C, respectively. The recurrence rate based on the (1) age was <40 years: 5.22% (6/115), 41-60 years: 16.1% (20/124), and >61 years: 3.07% (2/65); (2) gender was male: 13/139 (9.35%), female: 15/161 (9.32%); (3) BMI was obese: 17.57% (13/74), overweight: 11.6% (9/77), underweight: 6.35% (4/63), and normal weight: 2.33% (2/86); (4) degeneration scale was grades 1-2: 2% (1/50), grade 3: 7.4% (10/135), and grades 4-5: 14.8% (17/115); (5) modic change was type I: 25% (3/12), type II: 14.3% (1/7), type III: 33% (1/3), and no modic change: 8.27% (23/278); (6) number of involved disc herniation was 1 level: 3.9% (5/128), 2 level: 10.4% (13/125), 3 levels: 18.9% (7/37), and 4 levels: 30% (3/10); (7) history of discectomy was first: 8.83% (25/283) and repeated: 17.65% (3/17); (8) herniated disc level was L1-L2/L2-L3/L3-L4: 3.95% (3/76) and L4-L5: 14.6% (18/123); (9) disc height was <80%: 17.14% (6/35), 81%-100%: 8.16% (12/147), and >101%: 8.5% (10/118); (10) segmental dynamic motion was 1-10°: 8.58% (20/233) and 11-20° : 11.9% (8/67); (11) disc location was central: 7.41% (2/27), foraminal: 3.03% (2/66), and inferior/superior/paracentral: 11.59% (24/207); (12) radical annulotomy was 8.05% (7/87) vs. 9.86% (21/213); (13) approach method was transforaminal (inside-out): 11% (11/100), transforaminal (outside-in): 10% (10/100), and interlaminar: 7% (7/100); (14) early ambulation was 16.42% (23/140) vs. 3.13% (5/160); and (15) spinal orthosis application was 7.35% (10/136) vs. 10.98% (18/164). According to the above results, after summation of all scores, the early recurrence predicting score: recurrence rate ratio was 1-4: 0% (0/23), 5-8: 7.1% (13/183), 9-12: 8% (6/75) and 13-16 100% (10/10). CONCLUSIONS: Early recurrence after PELD is associated with several risk factors such as BMI, degeneration scale, combined HNP, and early ambulation. If we use the predicting score, we can postulate the occurrence of early recurrence after PELD. Knowing the predictive factors prior to surgical intervention will allow us to decrease the early recurrence rate after PELD.

Traumatic Cervical Epidural Hematoma without Osseous Fracture Presenting as Hemiparesis.

Traumatic cervical epidural hematoma (EDH) with no osseous fracture or underlying hematological abnormalities is a rare disorder that sometimes requires emergent surgical decompressive therapy. A 47-year-old woman was admitted to our emergency room due to severe neck pain and rapid onset hemiparesis after a car accident. Plain cervical radiographs and computed tomography scan did not reveal any abnormality. However, magnetic resonance imaging (MRI) revealed a large posterior EDH compressing the spinal cord extensively from C3 to C5. Emergent hematoma removal was performed following laminectomy, and subsequently the patient showed substantial clinical improvement. Complete removal of the hematoma was confirmed by MRI at 10 days after surgery. Here, the authors present a discussion of the etiology, pathogenesis, and prognosis of this rare pathologic entity.

Malignant Metastasis Misdiagnosed as Osteoporotic Compression Fracture: A Case Report.

In cases of vertebral collapse after a trivial injury in elderly patients with severe osteoporosis, it can be a diagnostic challenge to determine whether the cause is a benign compression fracture or malignant metastasis. A 78-year-old male patient was referred to the emergency department for the evaluation of weakness of the left lower limb. He had undergone percutaneous vertebroplasty four months earlier after being diagnosed with L3 osteoporotic compression fracture. He was treated with foraminotomy at the L3-4 level after being diagnosed with foraminal stenosis two months earlier at a spine clinic. Magnetic resonance (MR) images showed significant signal change from the vertebral body to the posterior element, and widely spreading extraspinal extension of soft tissue at L3. Computed tomography scan revealed osteolytic changes in regions including the ventral body and pedicle. Emergent decompressive laminectomy and bone biopsy were performed, and the histologic evaluation showed metastatic squamous cell carcinoma. A retrospective review of previous MR images showed obvious pedicle and facet involvement, and paraspinal extension of soft tissue, which are highly suggestive of malignant metastasis.