Pyogenic Andersson Lesion in a Patient With Ankylosing Spondylitis / 대한신경손상학회지

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.

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

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 fluoroscopyguided 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.

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

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 / 대한신경손상학회지

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.

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

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.

Traumatic Cervical Epidural Hematoma without Osseous Fracture Presenting as Hemiparesis / 대한신경손상학회지

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.

Posterior Screw Fixation in Previously Augmented Vertebrae with Bone Cement: Is It Inapplicable?

OBJECTIVE: The purpose of this study was to determine the feasibility of screw fixation in previously augmented vertebrae with bone cement. We also investigated the influence of cement distribution pattern on the surgical technique.METHODS: Fourteen patients who required screw fixation at the level of the previous percutaneous vertebroplasty or balloon kyphoplasty were enrolled in this study. The indications for screw fixation in the previously augmented vertebrae with bone cement included delayed complications, such as cement dislodgement, cement leakage with neurologic deficits, and various degenerative spinal diseases, such as spondylolisthesis or foraminal stenosis. Clinical outcomes, including pain scale scores, cement distribution pattern, and procedure-related complications were assessed.RESULTS: Three patients underwent posterior screw fixation in previously cemented vertebrae due to cement dislodgement or progressive kyphosis. Three patients required posterior screw fixation for cement leakage or displacement of fracture fragments with neurologic deficits. Eight patients underwent posterior screw fixation due to various degenerative spinal diseases. It was possible to insert screws in the previously augmented vertebrae regardless of the cement distribution pattern; however, screw insertion was more difficult and changed directions in the patients with cemented vertebrae exhibiting a solid pattern rather than a trabecular pattern. All patients showed significant improvements in pain compared with the preoperative levels, and no patient experienced neurologic deterioration as seen at the final follow-up.CONCLUSION: For patients with vertebrae previously augmented with bone cement, posterior screw fixation is not a contraindication, but is a feasible option.

Malignant Metastasis Misdiagnosed as Osteoporotic Compression Fracture: A Case Report / 대한신경손상학회지

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.

Posterior Screw Fixation in Previously Augmented Vertebrae with Bone Cement: Is It Inapplicable?

OBJECTIVE: The purpose of this study was to determine the feasibility of screw fixation in previously augmented vertebrae with bone cement. We also investigated the influence of cement distribution pattern on the surgical technique. METHODS: Fourteen patients who required screw fixation at the level of the previous percutaneous vertebroplasty or balloon kyphoplasty were enrolled in this study. The indications for screw fixation in the previously augmented vertebrae with bone cement included delayed complications, such as cement dislodgement, cement leakage with neurologic deficits, and various degenerative spinal diseases, such as spondylolisthesis or foraminal stenosis. Clinical outcomes, including pain scale scores, cement distribution pattern, and procedure-related complications were assessed. RESULTS: Three patients underwent posterior screw fixation in previously cemented vertebrae due to cement dislodgement or progressive kyphosis. Three patients required posterior screw fixation for cement leakage or displacement of fracture fragments with neurologic deficits. Eight patients underwent posterior screw fixation due to various degenerative spinal diseases. It was possible to insert screws in the previously augmented vertebrae regardless of the cement distribution pattern; however, screw insertion was more difficult and changed directions in the patients with cemented vertebrae exhibiting a solid pattern rather than a trabecular pattern. All patients showed significant improvements in pain compared with the preoperative levels, and no patient experienced neurologic deterioration as seen at the final follow-up. CONCLUSION: For patients with vertebrae previously augmented with bone cement, posterior screw fixation is not a contraindication, but is a feasible option.

Adjacent Bilateral Stress Pedicle Fractures after Instrumented Lumbar Fusion: A Case Report / 대한신경손상학회지

Bilateral pedicle stress fractures are rare even in the elderly. Bilateral pedicle fractures are due to post-surgical complications at the level of fusion or stress related activities in most cases. The authors describe a unique case of adjacent L4 bilateral pedicle fractures, which developed 4 years after anterior lumbar interbody fusion with bone cement augmented screw fixation at the L5-S1 level. As far as the authors' knowledge, no similar case has been previously reported in the literature. The pathophysiological mechanism of this rare entity is discussed with review of relevant literature.

Severe Retrolisthesis at the Adjacent Segment after Lumbar Fusion Combined with Dynamic Stabilization / 대한신경손상학회지

Lumbar fusion using the pedicle screw system is a popular operative procedure, with favorable clinical results and high fusion rates. However, the risk of adjacent segment disease after lumbar fusion is problematic. We report a complicated case of severe retrolisthesis at L3-4 level following dynamic interspinous process stabilization at L2-3 level and a fusion at L4-5 level. The radiological and clinical findings of this complication are discussed, and a review of the literature is presented.

Lumbar Disc Herniation Presented with Contralateral Symptoms

OBJECTIVE: This study aimed to unravel the putative mechanism underlying the neurologic deficits contralateral to the side with lumbar disc herniation (LDH) and to elucidate the treatment for this condition. METHODS: From January 2009 to June 2015, 8 patients with LDH with predominantly contralateral neurologic deficits underwent surgical treatment on the side with LDH with or without decompressing the symptomatic side. A retrospective review of charts and radiological records of these 8 patients was performed. The putative mechanisms underlying the associated contralateral neurological deficits, magnetic resonance imaging (MRI), electromyography (EMG), and the adequate surgical approach are discussed here. RESULTS: MRI revealed a similar laterally skewed paramedian disc herniation, with the apex deviated from the symptomatic side rather than directly compressing the nerve root; this condition may generate a contralateral traction force. EMG revealed radiculopathies in both sides of 6 patients and in the herniated side of 2 patients. Based on EMG findings and the existence of suspicious lateral recess stenosis of the symptomatic side, 6 patients underwent bilateral decompression of nerve roots and 2 were subjected to a microscopic discectomy to treat the asymptomatic disc herniation. No specific conditions such as venous congestion, nerve root anomaly or epidural lipomatosis were observed, which may be considered the putative pathomechanism causing the contralateral neurological deficits. The symptoms resolved significantly after surgery. CONCLUSION: The traction force generated on the contralateral side and lateral recess stenosis, rather than direct compression, may cause the contralateral neurologic deficits observed in LDH.

Clinical Features of Herniated Disc at Cervicothoracic Junction Level Treated by Anterior Approach

OBJECTIVE: The anterior approach for C7-T1 disc herniation may be challenging because of obstruction by the manubrium and the narrow operative field. This study aimed to investigate the clinical and neurological outcomes of anterior approach for C7-T1 disc herniation. METHODS: We retrospectively evaluated 13 patients who underwent the anterior approach for C7-T1 disc herniation by a single surgeon within a period of 11 years (2003-2014). The minimum follow-up duration was 6 months. We describe the clinical presentation, radiographic findings, neurological outcome, and related complications. RESULTS: Of 372 patients with single-level anterior discectomy and fusion or artificial disc replacement for cervical disc herniation, 13 (3.5%) had C7-T1 disc herniation. The main clinical presentation was unilateral motor weakness in intrinsic hand muscles (11 patients), along with numbness, pain, and tingling sensation that radiate down the arm to the little finger. Most of the patients improved after surgery via the anterior approach. Ten patients underwent successful anterior discectomy and fusion by the standard supramanubrial Smith-Robinson approach, but 2 needed additional manubriotomy and sternotomy. In 1 patient, we performed surgery at a wrong level because the correct level was difficult to identify intraoperatively. Two patients had transient vocal dysfunction, but none had major complications related to injuries of the great vessels such as the thoracic duct or esophagus. CONCLUSION: For patients who require direct anterior decompression for C7-T1 disc herniation, the anterior approach is relatively feasible. However, care should be taken to overcome physical constraints by the manubrium and slope.

Acute Cervical Subdural Hematoma with Quadriparesis after Cervical Transforaminal Epidural Block

Cervical epidural steroid injection is frequently used in the conservative management of neck pain and cervical radiculopathy. Epidural cervical transforaminal injections are usually well-tolerated with mild side effects such as transient decreased sensory and motor function, or headache due to dural puncture. Although there are a few case reports about adverse effects of cervical epidural injection in the literature, it can cause severe complications such as large hematoma, infarction by spinal vascular injury. Subdural hematoma has been occurred much less common rather than epidural hematoma in the spinal cord. We report a rare catastrophic case of cervical spinal subdural hematoma with quadriparesis after cervical transforaminal epidural block.

Contralateral Juxtafacet Cyst Development after the Spontaneous Resolution of a Previous Facet Cyst

Juxtafacet cysts are implicated in neural compression. Thus far, it is known that surgical removal is the definitive treatment for symptomatic juxtafacet cyst because spontaneous regression is rare, and the failure rate of conservative treatment is high. We have reported a rare case of right-sided juxtafacet cyst development after the spontaneous resolution of contralateral left-sided facet cyst. The left-sided facet cyst resolved spontaneously without surgical treatment, but a juxtacyst developed on the contralateral facet on the right side, as illustrated on 4-year follow-up magnetic resonance images. To the best of our knowledge, this is the first report of newly developed contralateral juxtafacet cyst after spontaneous regression. Herein, we have discussed the natural history and the management of this rare case.

Lying Down Instability Undetected on Standing Dynamic Radiographs

It is well known that spinal instability should be evaluated in the standing lateral position. Standing dynamic flexion and extension radiographs are usually used to assess spinal instability. Here, we report a patient who experienced distraction instability while in the supine position rather than the standard standing position. To our knowledge, this is the first report of lying-down instability undetected on standing dynamic flexion and extension radiographs. We discuss the pathophysiological mechanism of this uncommon but possible entity and provide a review of the literature.

Cauda Equina Syndrome Caused by Idiopathic Epidural Lipomatosis

Spinal epidural lipomatosis (SEL) is a rare condition that presents as a back pain with progressive neurologic symptoms. Most affected patients are obese and receiving steroid therapy, or have an endocrinopathies. We report a rare case of cauda equina syndrome caused by SEL in a non-obese healthy young man without any evident traumatic episode. A healthy 19-year-old man, who had experienced lower back pain for two months, visited our emergency room because of the sudden development of motor weakness and voiding difficulty. Lumbar magnetic resonance image revealed extradural fat compressing the cauda equina. Urgent decompression via posterior laminectomy and excision of excess epidural fat resulted in an immediate symptom improvement.

Unilateral Pedicle Fracture Accompanying Spondylolytic Spondylolisthesis

Unilateral pedicle stress fracture accompanying spondylolytic spondylolisthesis is rare even in the elderly. Most are associated with major trauma, previous spine surgery, or stress-related activity. Here, the authors describe an unique case of unilateral pedicle fracture associated with spondylolytic spondylolisthesis at the L5 level, which was successfully treated by posterior lumbar interbody fusion with screw fixation at the L5-S1 level. As far as the authors' knowledge, no such case has been previously reported in the literature. The pathophysiological mechanism of this uncommon entity is discussed and a review of relevant literature is included.

Posterior Epidural Migration of an Extruded Lumbar Disc Mimicking a Facet Cyst: A Case Report

Dorsal extradural migration of extruded disc material is clinically uncommon. We report a rare case of posterior epidural migration of an extruded lumbar disc mimicking a facet cyst. A 32-year-old man was admitted to our institute with a 2-week history of severe low back pain and radiating pain in the left leg. The magnetic resonance (MR) images revealed a dorsally located, left-sided extradural cystic mass at the L2-3 level. The initial diagnosis was an epidural facet cyst because of the high signal intensity on MR images and its location adjacent to the facet joint. Intraoperatively, an encapsulated mass of soft tissue adherent to the dural sac was observed and excised. The pathological diagnosis was degenerated disc material. After surgery, the patient experienced complete relief from leg pain.