Increased Prevalence of Ossification of Posterior Longitudinal Ligament and Increased Bone Mineral Density in Patients with Ossification of Nuchal Ligament

OBJECTIVE: There are also few studies demonstrating the relationship between ossification of nuchal ligament (ONL) and ossification of posterior longitudinal ligament (OPLL). We compared the prevalence, location, and type of OPLL between patients with ONL and matched patients without ONL.We also compared the bone mineral densities (BMDs) between the 2 groups. METHODS: total of 124 cervical ONL patients were enrolled in this study. The control group of 124 patients was matched with 124 patients with ONL by age and sex on a 1:1 basis to minimize confounding factors. We reviewed the prevalence, location, and type of OPLL in both groups. RESULTS: The prevalence of OPLL was almost 2.5 times greater in patients with ONL than those without ONL. The mean value of BMD in patients with ONL was greater at the lumbar spine (L1-L4) than in patients without ONL. The mean T score of the lumbar spine was 0.25±1.68 in the patients with ONL and -0.73±1.64 in the patients without ONL. CONCLUSION: The prevalence of OPLL in patients with ONL was significantly higher than in patients without ONL. Because ONL is innocuous and may be seen more readily than OPLL on simple cervical radiographs, clinicians should consider the possibility of coexisting OPLL when ONL, especially extensive ONL, is detected in patients with neck pain, radiculopathy, or myelopathy, to facilitate proper treatment.

The Clinical Significance of Ossification of Ligamentum Nuchae in Simple Lateral Radiograph : A Correlation with Cervical Ossification of Posterior Longitudinal Ligament

OBJECTIVE: Ossification of the ligamentum nuchae (OLN) is usually asymptomatic and incidentally observed in cervical lateral radiographs. Previous literatures reported the correlation between OLN and cervical spondylosis. The purpose of this study was to elucidate the clinical significance of OLN with relation to cervical ossification of posterior longitudinal ligament (OPLL). METHODS: We retrospectively compared the prevalence of OPLL in 105 patients with OLN and without OLN and compared the prevalence of OLN in 105 patients with OPLL and without OPLL. We also analyzed the relationship between the morphology of OLN and involved OPLL level. The OPLL level was classified as short (1-3) or long (4-6), and the morphologic subtype of OLN was categorized as round, rod, or segmented. RESULTS: The prevalence of OPLL was significantly higher in the patients with OLN (64.7%) than without OLN (16.1%) (p=0.0001). And the prevalence of OLN was also higher in the patients with OPLL (54.2%) than without OPLL (29.5%) (p=0.0002). In patients with round type OLN, 5 of 26 (19.2%) showed long level OPLL, while in patients with larger type (rod and segmented) OLN, 22 of 42 (52.3%) showed long level OPLL (p=0.01). CONCLUSION: There was significant relationship between OLN and OPLL prevalence. This correlation indicates that there might be common systemic causes as well as mechanical causes in the formation of OPLL and OLN. The incidentally detected OLN in cervical lateral radiograph, especially larger type, might be helpful to predict the possibility of cervical OPLL.

The Comparison of Sagittal Spinopelvic Parameters between Young Adult Patients with L5 Spondylolysis and Age-Matched Control Group

OBJECTIVE: To compare spinopelvic parameters in young adult patients with spondylolysis to those in age-matched patients without spondylolysis and investigate the clinical impact of sagittal spinopelvic parameters in patients with L5 spondylolysis. METHODS: From 2009 to 2012, a total of 198 young adult male patients with spondylolysis were identified. Eighty age-matched patients without spondylolysis were also selected. Standing lateral films that included both hip joints were obtained for each subject. Pelvic incidence (PI), sacral slope (SS), pelvic tilt, lumbar lordosis angle, sacral inclination, lumbosacral angle, and sacral table angle were measured in both groups. A comparative study of the spinopelvic parameters of these two groups was performed using SPSS 15.0 (SPSS Inc., Chicago, IL, USA). RESULTS: Among the aforementioned spinopelvic parameters, PI, SS and STA were significantly different between patients with spondylolysis and those without spondylolysis. PI and SS were higher in the spondylolysis group than in the control group, but STA was lower in the spondylolysis group than in the control group. CONCLUSION: PI and SS were higher in the spondylolysis group than in the control group, but STA was lower in the spondylolysis group than in the control group. Patients with spondylolysis have low STA at birth, which remains constant during growth; a low STA translates into high SS. As a result, PI is also increased in accordance with SS. Therefore, we suggest that STA is an important etiologic factor in young adult patients with L5 spondylolysis.

Delayed Retroperitoneal Hemorrhage due to Lumbar Artery Pseudoaneurysm after Lumbar Posterolateral Fusion

A 55-year-old female patient presented with lower back pain and neurogenic intermittent claudication and underwent L3-L4 posterolateral fusion. To prepare the bone fusion bed, the transverse process of L3 and L4 was decorticated with a drill. On the 9th post-operative day, the patient complained of a sudden onset of severe abdominal pain and distension. Abdominal computed tomography revealed retroperitoneal hematoma in the right psoas muscle and iatrogenic right L3 transverse process fracture. Lumbar spinal angiography showed the delayed hematoma due to rupture of the 2nd lumbar artery pseudoaneurysm and coil embolization was done at the ruptured lumbar artery pseudoaneusyrm. Since then, the patient's postoperative progress proceeded normally with recovery of the hemodynamic parameters.

Posterior Cervical Fixation with a Nitinol Shape Memory Loop for Primary Surgical Stabilization of Atlantoaxial Instability: A Preliminary Report

OBJECTIVE: To evaluate a new posterior atlantoaxial fixation technique using a nitinol shape memory loop as a simple method that avoids the risk of vertebral artery or nerve injury. METHODS: We retrospectively evaluated 14 patients with atlantoaxial instability who had undergone posterior C1-2 fusion using a nitinol shape memory loop. The success of fusion was determined clinically and radiologically. We reviewed patients' neurologic outcomes, neck disability index (NDI), solid bone fusion on cervical spine films, changes in posterior atlantodental interval (PADI), and surgical complications. RESULTS: Solid bone fusion was documented radiologically in all cases, and PADI increased after surgery (p<0.05). All patients remained neurologically intact and showed improvement in NDI score (p<0.05). There were no surgical complications such as neural tissue or vertebral artery injury or instrument failure in the follow-up period. CONCLUSION: Posterior C1-2 fixation with a nitinol shape memory loop is a simple, less technically demanding method compared to the conventional technique and may avoid the instrument-related complications of posterior C1-2 screw and rod fixation. We introduce this technique as one of the treatment options for atlantoaxial instability.

New Diagnostic Tool for Far Lateral Lumbar Disc Herniation : The Clinical Usefulness of 3-Tesla Magnetic Resonance Myelography Comparing with the Discography CT

OBJECTIVE: To prospectively assess the diagnostic and clinical value of a new technique (3-tesla magnetic resonance myelography, 3T MRM) as compared to computed tomographic discography (disco-CT) in patients with far lateral disc herniation. METHODS: We evaluated 3T MRM and disco-CT of 25 patients, whom we suspected of suffering from far lateral disc herniation. Using an assessment scale, 4 observers examined independently both 3T MRM and disco-CT images. We analyzed observer agreement and the accentuation of each image. RESULTS: We found complete matching, and observer agreement, between high resolution images of 3T MRM and disco-CT for diagnosing far lateral disc herniation. CONCLUSION: We think noninvasive 3T MRM is an appropriate diagnostic tool for far lateral disc herniation as compared to disco-CT.

Intradural Migration of a Sequestrated Lumbar Disc Fragment Masquerading as a Spinal Intradural Tumor

Intervertebral intradural lumbar disc herniation (ILDH) is a quite rare pathology, and isolated intradural lumbar disc herniation is even more rare. Magnetic resonance imaging (MRI) may not be able to reveal ILDHs, especially if MRI findings show an intact lumbar disc annulus and posterior longitudinal ligament. Here, we present an exceedingly rare case of an isolated IDLH that we initially misidentified as a spinal intradural tumor, in a 54-year-old man hospitalized with a 2-month history of back pain and right sciatica. Neurologic examination revealed a positive straight leg raise test on the right side, but he presented no other sensory, motor, or sphincter disturbances. A gadolinium-enhanced MRI revealed what we believed to be an intradural extramedullary tumor compressing the cauda equina leftward in the thecal sac, at the L2 vertebral level. The patient underwent total L2 laminectomy, and we extirpated the intradural mass under microscopic guidance. Histologic examination of the mass revealed a degenerated nucleus pulposus.

Changes in Dermatomal Somatosensory Evoked Potentials according to Stimulation Intensity and Severity of Carpal Tunnel Syndrome

OBJECTIVE: To investigate the change of latency of cervical dermatomal somatosensory evoked potential (DSEP) according to stimulation intensity (SI) and severity of carpal tunnel syndrome (CTS). METHODS: Stimulation sites were the C6, C7, and C8 dermatomal areas. Two stimulation intensities 1.5xsensory threshold (ST) and 2.5xST were used on both normal and CTS patients. RESULTS: In moderate CTS, the latencies of C6 and C7 DSEP during 1.5xST SI and those of C7 DSEP during 2.5xST SI were significantly delayed compared with the values of normal subjects. Significant correlation between the latency of C7 DSEP of 2.5xST stimulation and the median sensory nerve conduction velocity was observed. CONCLUSION: We suggest that these data can aid in the diagnosis of cervical sensory radiculopathy using low stimulation intensity and of those who have cervical sensory radiculopathy combined with CTS patients.

Radiological and Clinical Results of Laminectomy and Posterior Stabilization for Severe Thoracolumbar Burst Fracture : Surgical Technique for One-Stage Operation

OBJECTIVE: This study aimed to show the possibility of neural canal enlargement and restoration of bony fragments through laminectomy and minimal facetectomy without pediculectomy or an anterior approach, and also to prove the adequacy of posterior stabilization of vertebral deformities after thoracolumbar bursting fracture. METHODS: From January 2003 to June 2009, we experienced 45 patients with thoracolumbar burst fractures. All patients enrolled were presented with either a neural canal compromise of more than 40% with a Benzel-Larson Grade of VI, or more than 30% compromise with less than a Benzel-Larson Grade of V. Most important characteristic of our surgical procedure was repositioning retropulsed bone fragments using custom-designed instruments via laminectomy and minimal facetectomy without removing the fractured bone fragments. Beneath the dural sac, these custom-designed instruments could push the retropulsed bone fragments within the neural canal after the decompression and bone fragment repositioning. RESULTS: The mean kyphotic deformities measured preoperatively and at follow-up within 12 months were 17.7 degrees (+/-6.4 degrees) and 9.6 degrees (+/-5.2 degrees), respectively. The mean midsagittal diameter improved from 8.8 mm (+/-2.8 mm) before surgery to 14.2 mm (+/-1.6 mm) at follow-up. The mean traumatic vertebral body height before surgery was 41.3% (+/-12.6%). At follow-up assessment within 12 months, this score showed a statistically significant increase to 68.3% (+/-12.8%). Neurological improvement occurred in all patients. CONCLUSION: Though controversy exists in the treatment of severe thoracolumbar burst fracture, we achieved effective radiological and clinical results in the cases of burst fractures causing severe canal compromise and spinal deformity by using this novel custom-designed instruments, via posterior approach alone.

A Dumbbell-Shaped Meningioma Mimicking a Schwannoma in the Thoracic Spine

A 50-year-old man presented bilateral hypesthesia on and below the T6 dermatome and paresthesia. Magnetic resonance imaging (MRI) showed an intraspinal extradural tumor, which located from the 6th thoracic vertebral body to the upper margin of the 7th vertebral body, continuing dumbbell-like through the intervertebral foramen into the right middle thorax suggesting a neurogenic tumor (neurofibroma or neurilemmoma). With the patient in a prone position, we exposed and excised the tumor via a one stage posterior approach through a hemi-laminictomy of T6. Histologic examination showed a grade 1 meningothelial meningioma, according to the World Health Organization classification. Initially, we assumed the mass was a schwannoma because of its location and dumbbell shape. However, the tumor was actually a meningioma. Postoperatively, hypesthesia resolved completely and motor power of the leg gradually full recovered. A postoperative MRI revealed no evidence of residual tumor.

Monostotic Paget's Disease of the Lumbar Spine Mimicking Vertebral Metastasis: A Case Report

Paget's disease of the bone is the second-most-common metabolic bone disease. However, it is rarely found in the Far East. Vertebral Paget's disease usually occurs at multiple vertebral levels, with less than 20% of vertebral Paget's disease being monostotic. Here, we present a rare case of monostotic vertebral Paget's disease, which we initially misdiagnosed as a spinal metastasis. A 34-year-old man was admitted with a one-month history of lower back pain. Initially, computed tomography of the lumbar spine showed an osteolytic change of the L4 and mild expansion of the L4 vertebral body. Subsequently, magnetic resonance imaging showed a highly homogenously enhanced L4 vertebral body. We performed positron-emission tomography, bone scan, and tumor marker evaluation. However, we could not detect any likely primary origin of the spinal metastasis. Therefore, we carried out a needle bone biopsy under fluoroscopic guidance, and the bone specimen revealed Paget's disease of the bone.

Reference Data of Cervical Dermatomal Somatosensory Evoked Potentials Using Low Intensity Stimulation and Report of 2 Cases

OBJECTIVE: To establish reference data for dermatomal somatosensory evoked potentials (DSEP) using a stimulation intensity lower than what is conventionally utilized. METHOD: Fifty subjects (25 older adults>48 years old; 25 younger adults<32 years old) without history of neck pain or cervical spine surgery were enrolled. The DSEP study was performed with stimulation intensities of 1.0, 1.5, and 2.5 times sensory threshold (ST) on right arms for C5, C6, C7, and C8 dermatomes. RESULTS: The mean latencies of DSEP stimulating C5, C6, C7, and C8 dermatomes with 1.5 times ST intensity were 17.6+/-1.7 ms, 22.2+/-2.1 ms, 22.8+/-1.4 ms, and 22.6+/-1.8 ms, respectively. The mean amplitude (N1P1) of DSEP stimulating C5, C6, C7, and C8 dermatomes with 1.5 times ST intensity were 0.9+/-0.4 microV, 0.9+/-0.5 microV, 1.0+/-0.6 microV, and 1.1+/-0.8 microV, respectively. The C5, C6, C7, and C8 DSEP were evoked in 84%, 98%, 100%, and 96% of cases with 2.5 times ST compared to 64%, 56%, 60%, and 62% with 1.5 times ST, respectively. When one DSEP was not evoked, the DSEP of the opposite side was evoked only in 2 subjects. CONCLUSION: This study provides the reference data of DSEP with lower stimulation intensities than are conventionally utilized. Additionally, two cases of clinical significance were reported.

Treatment for Patients with Acute Ischemic Stroke Presenting beyond Six Hours of Ischemic Symptom Onset : Effectiveness of Intravenous Direct Thrombin Inhibitor, Argatroban

OBJECTIVE: The objectives of this study were to analyze the outcome and hemorrhagic risk of intravenous (IV) argatroban in patients with acute ischemic stroke presenting beyond six hours of ischemic symptom onset. METHODS: Eighty patients with acute ischemic stroke who were admitted to the hospital beyond six hours from ischemic symptom onset were retrospectively analyzed. We could not perform IV thrombolysis or intra-arterial thrombolysis because of limited time window. So, IV argatroban was performed to prevent recurrent thrombosis and progression of infarcted area. The outcome was assessed by the National Institute of Health Stroke Scale (NIHSS) score and related hemorrhagic risk was analyzed. Also, each outcome was analyzed according to the initial stroke severity, subtype, and location. RESULTS: The median NIHSS was 8.0 at admission, 4.1 upon discharge, and 3.3 after three months. A good outcome was achieved in 81% of patients upon discharge and 88% after three months. Symptomatic hemorrhage occurred in only two patients (3%). IV argatroban was effective regardless of initial stroke severity, subtype, and location. CONCLUSION: IV argatroban may be an effective and safe treatment modality for acute ischemic stroke presenting beyond six hours of ischemic symptom onset.

Dysphagia Caused by Ossificaion of the Cervical Anterior Longitudial Ligament : Report of Two Cases

We report two cases with progressive dysphagia and foreign body sensation resulted from severe cervical ossification of the anterior longitudinal ligament (OALL). A 63-years-old male presented progressive dysphagia and foreign body sensation with neck pain. Cervical computed tomography (CT) and magnetic resonance images (MRI) revealed diffuseOALL from C2 to C7 with esophageal compression by most severe OALL of C5, C6, C7 and spondylotic stenosis of C5- 6, C6-7. OALL removal of C5, 6, 7 and discectomy with interbody fusion via anterior approach was performed. The other 56-years-old female presented progressive dysphagia with foreign body sensation. Cervical CT and MRI revealed severe OALL of C4, 5, 6, 7 with esophageal compression and surgical removal was performed. In both patients, dysphagia and foreign body sensation was immediately relieved after operation and the distance between trachea and each cervical body was increased than preoperative distance in cervical lateral view.

Multimodal Therapy for Patients with Acute Ischemic Stroke : Outcomes and Related Prognostic Factors

OBJECTIVE: The objectives of this study were to analyze the recanalization rates and outcomes of multimodal therapy that consisted of sequential intravenous (IV)/intra-arterial (IA) thrombolysis, mechanical thrombolysis including mechanical clot disruption using microcatheters and microwires, balloon angioplasty, and stenting for acute ischemic stroke, and to evaluate the prognostic factors related to the outcome. METHODS: Fifty patients who were admitted to the hospital within 8 hours from ischemic symptom onset were retrospectively analyzed. Initial IV thrombolysis and subsequent cerebral angiography were performed in all patients. If successful recanalization was not achieved by IV thrombolysis, additional IA thrombolysis with mechanical thrombolysis, including balloon angioplasty and stenting, were performed. The outcomes were assessed by the National Institute of Health Stroke Scale (NIHSS) change and modified Rankin scale (mRS) and prognostic factors were analyzed. RESULTS: Successful recanalization was achieved in 42 (84%) of 50 patients, which consisted of 8 patients after IV thrombolysis, 19 patients after IA thrombolysis with mechanical clot disruption, and 15 patients after balloon angioplasty or stenting. Symptomatic hemorrhage occurred in 4 (8%) patients. Good outcomes were achieved in 76% and 70% of patients upon discharge, and 93% and 84% of patients after 3 months according to the NIHSS change and mRS. The initial clinical status, recanalization achievement, and presence of symptomatic hemorrhage were statistically related to the outcomes. CONCLUSION: Multimodal therapy may be an effective and safe treatment modality for acute ischemic stroke. Balloon angioplasty and stenting is effective for acute thrombolysis, and produce higher recanalization rates with better outcomes.

Congenital Absence of a Cervical Spine Pedicle : Report of Two Cases and Review of the Literature

Congenital absence of a cervical spine pedicle is a rare clinical entity, and it is usually found incidentally on radiological studies performed after trauma in patients with cervical pain. We report two cases of congenital absence of a cervical spine pedicle and present a review of the literature.

Seizure Control in Patients with Extratemporal Lobe Epilepsy

OBJECTIVE: This study was designed to analyze seizure outcome and to investigate the prognostic factors for predicting seizure outcome according to the preoperative evaluations, surgical procedures, topectomy sites and histopathological findings in patients with extratemporal lobe epilepsy (ETLE). METHODS: This study comprised 63 patients with ETLE who underwent surgery. Preoperative evaluations included semiologic analysis, chronic video-EEG monitoring, and neuroimaging studies. Surgical procedures consisted of topectomy in 51 patients, corpus callosotomy in 9, functional hemispherectomy in 2, and vagus nerve stimulation (VNS) in 1. Histopathological findings were reviewed. Postoperative seizure outcomes were assessed by Engel's classification at the average follow up period of 66.8 months. Chi-square test was used for statistics. RESULTS: Total postoperative seizure outcomes were class I in 51 (80%) patients, class II in 6 (10%), class III in 6 (10%). Patients with structural abnormalities on neuroimaging study showed class I in 49 (88%) patients (p0.05). CONCLUSION: A good seizure outcome was obtained in patients with ETLE. The factors for favorable seizure outcome are related to the presence of structural abnormalities on neuroimaging study, and focal and regional ictal EEG onset.

Clinical and Radiologic Assessment for Anterior Cervical Interbody Fusion with Synthetic Cages

OBJECTIVE: This purpose of this study was to determine the clinical efficiency and applicability, and to analyze the radiologic findings of the anterior cervical approach using two synthetic cages for interbody fusion. METHODS: A total of 41 patients with cervical diseases underwent anterior discectomy and interbody fusion with the PEEK Solis(TM) cage in 21 patients and the carbon composite Osta-Pek(TM) cage in 20 patients. Outcome assessment was done using Odom's criteria. Radiological assessment was performed with respect to subsidence, bony fusion and lordosis. The mean follow-up period was 13 months. RESULTS: There were 34 (92.9%) successful cases. The average height of the disc space 12 months after surgery compared to the height before surgery was increased in 28 cases. The height of the disc space 12 months after surgery compared to the height just after surgery was decreased over 3mm in 4 cases, indicating severe subsidence. The use of these synthetic cages have provided the increase in postoperative cervical lordosis. CONCLUSION: There were no significant differences between the Solis(TM) and Osta-Pek(TM) cages on clinical and radiologic outcomes. Both Solis(TM) and Osta-Pek(TM) cages showed low subsidences and complications associated with hardware with good clinical outcomes, high fusion rates, restored disc heights, and restored cervical lordosis.

Spinal Intramedullary Lipoma without Dysraphism

Spinal cord lipomas are commonly associated with spinal dysraphism. The lipomas without spinal dysraphism have been reported to be only 1% of all spinal cord lipomas. We report two cases of patients with spinal intramedullary lipomas without dysraphism. One patient was a 57-year-old man who had lower back pain and right-sided sciatica for 20 years. Magnetic resonance imaging (MRI) of the spine demonstrated an intradural mass occupying L1 to L2. The other patient was a 27-year-old woman who had back pain and gait disturbance for 5 months. MRI of the spine showed an elongated intradural mass occupying T7 to T9. Total laminectomy with partial resection of the lesions was performed on both patients. Pathological studies confirmed the diagnosis of spinal cord lipoma. They exhibited no dysraphism. Postoperatively, neurological symptoms improved in both patients.

Diagnostic Usefulness of Dermatomal Somatosensory Evoked Potentials by Low Intensity Stimulation in Lumbar Radiculopathy

OBJECTIVE: To investigate diagnostic usefulness of dermatomal somatosensory evoked potentials (DSEP) in the evaluation of lumbar radiculopathy using stimulation intensity lower than conventional stimulation intensity. METHOD: Fifty-seven patients with low back pain were studied with DSEP and needle electromyography (EMG). The radiculopathy was diagnosed by lumbar MRI or operative findings. The DSEP study was performed with stimulation intensity of 1.0x, 1.5x, 2.5x sensory threshold, respectively. We compared the sensitivity and specificity of DSEP and needle EMG in the evaluation of L5 radiculopathy. RESULTS: Radiological and operative findings revealed unilateral herniated disc and L5 root compression in 38 patients (66.7%). Nineteen patients had no significant L5 root compression. The sensitivity and specificity of abnormality were 68.4% and 78.9% in 1.0x sensory threshold stimulation; 71.1%, 78.9% in 1.5x sensory threshold stimulation; and 44.7%, 84.2% in 2.5x sensory threshold stimulation, respectively. Whereas they were 55.2% and 100% in needle EMG. CONCLUSION: DSEP using low stimulus intensity showed higher sensitivity in the diagnosis of L5 radilculopathy, and DSEP might provide additional diagnostic usefulness in the evaluation of patients with suspected L5 radiculopathy.