Accurate and Minimally Invasive Cervical Pedicle Screw Insertion Procedure Using the Bone Biopsy Needle as Drill Guide.

INTRODUCTION: Cervical pedicle screw (CPS) fixation provides the strongest mechanical stability. It needs, however, wide soft tissue detachment to expose the entry point and carries the potential risk of iatrogenic damage to neurovascular structures. Malposition of the CPS cannot be completely avoided even using the navigation system. TECHNICAL NOTE: Using the bone biopsy needle as drill guide, we developed a novel accurate CPS insertion technique. (1) The entry point of CPS was exposed using Southwick's technique for anterior fixation or Tokioka's technique for posterior fixation. (2) A 13G bone biopsy needle was inserted from the entry point established by the fluoroscopy-assisted pedicle axis view technique described by Yukawa et al. to within a few millimeters of the pedicle. (3) The external sleeve of the bone biopsy needle was left in place as a drill guide, and the 1.25 mm guidewire for a 4.0 mm cannulated screw was then inserted into the pedicle cavity. (4) The external sleeve of the bone biopsy needle was removed, and the screw trajectory was created by a 2.7 mm cannulated drill bit over the guidewire. (5) Tapping was conducted prior to CPS insertion. Using this method, 29 CPSs in nine patients were inserted. Postoperative computed tomography scans revealed that all the CPSs were placed accurately. CONCLUSIONS: Utilizing the bone biopsy needle as drill guide, our procedure enables accurate positioning of CPS without expensive instruments.

Anterior Decompression and Fusion Versus Laminoplasty for Cervical Myelopathy Caused by Soft Disk Herniation: A Long-term Prospective Multicenter Study.

STUDY DESIGN: A prospective multicenter study. OBJECTIVE: The purpose of this study was to determine whether laminoplasty (LP) is comparable for myelopathy caused by cervical disk herniation (CDH). SUMMARY OF BACKGROUND DATA: Anterior decompression and fusion (ADF) has conventionally been used for myelopathy caused by CDH with stable outcomes. However, recurrence of myelopathy due to adjacent segment degeneration are its drawbacks. The efficacy of LP without discectomy has been sporadically reported, but no long-term prospective study has been conducted to verify it. MATERIALS AND METHODS: Patients with cervical myelopathy caused by CDH were studied. The first 30 patients and the next 30 patients were treated with ADF and LP, respectively. The outcomes were compared between the 22 ADF patients and the 20 LP patients who had completed the follow-up examination scheduled 10 years after surgery. RESULTS: There was no statistically significant difference in the postoperative severity or recovery rate of myelopathy between the 2 groups 10 years after surgery. One patient in the ADF group underwent LP for secondary myelopathy due to adjacent segment degeneration 2 years after the surgery. Reoperation was not required for patients in the LP group. Postoperative neck pain was significantly more severe in the LP group than in the ADF group. CONCLUSIONS: ADF and LP for cervical myelopathy caused by CDH achieve similarly favorable outcomes. Recurrence of myelopathy caused by adjacent segment degeneration is a disadvantage of ADF while residual neck pain is a disadvantage of LP.

Analysis of risk factors for hyponatremia in patients with acute spinal cord injury: a retrospective single-institution study in Japan.

STUDY DESIGN: Retrospective single-institution observational study. OBJECTIVE: Spinal cord injury (SCI) is associated with a high prevalence of hyponatremia, which can cause various clinical symptoms and increase mortality. We aimed to analyze the risk factors for hyponatremia in patients with acute SCI. SETTING: Trauma Center, Tohoku University Hospital, Japan METHODS: We reviewed the medical records of patients with SCI admitted between January 2008 and November 2016. Least angle regression analyses was performed to assess the association between hyponatremia and other parameters. RESULTS: Of the 213 enrolled patients, 85 (40%) had hyponatremia (serum Na < 135 mmol/L) whilst 19 (9%) had severe hyponatremia (serum Na < 130 mmol/L). Least angle regression analyses revealed that hyponatremia was significantly associated with higher American Spinal Injury Association impairment scale, nosocomial pneumonia, deep vein thrombosis, bradycardia, and surgery for SCI before developing hyponatremia. Severe hyponatremia was significantly associated with traumatic brain injury with an abbreviated injury scale score ≥3, higher American Spinal Injury Association impairment scale, bradycardia, vasopressors, and nosocomial pneumonia. CONCLUSION: Various factors including traumatic brain injury with an abbreviated injury scale score ≥3 and higher American Spinal Injury Association impairment scale may be associated with hyponatremia in patients with acute SCI. These factors can help clinicians identify and monitor SCI patients with a higher hyponatremia risk, and potentially help patients to avoid severe complications.

Postoperative Changes in Presepsin Level and Values Predictive of Surgical Site Infection After Spinal Surgery: A Single-Center, Prospective Observational Study.

STUDY DESIGN: Single-institutional, prospective observational study. OBJECTIVE: To elucidate the perioperative kinetics of presepsin (PSEP) in patients undergoing spinal surgery, and to evaluate the possibility of PSEP in the early diagnosis of surgical site infection (SSI). SUMMARY OF BACKGROUND DATA: Early diagnosis of SSI after spinal surgery is important. Although several biomarkers have been used as early indicators of SSI, the specificity of these markers in SSI diagnosis was not high. PSEP was found as a novel diagnostic marker for bacterial sepsis in 2004. However, its kinetics after spinal surgery and its usefulness in early diagnosis of SSI have never been evaluated. METHODS: A total of 118 patients who underwent elective spinal surgery were enrolled. PSEP was measured before, immediately after, 1 day after, and 1 week after surgery. In patients without postoperative infection, perioperative kinetics of PSEP were analyzed. PSEP levels in patients with postoperative infection were also recorded separately, and their utility in SSI diagnosis was evaluated. RESULTS: In the 115 patients without postoperative infection, the median PSEP value was 126, 171, 194, and 147 pg/mL before, immediately after, 1 day after, and 1 week after surgery, respectively. Compared with the preoperative value, PSEP was significantly higher immediately after surgery and the next day, and return to the preoperative level 1 week after surgery. The estimated reference value for 95 percentile in patients without postoperative infection was 297 pg/mL 1 week after surgery. In three patients with postoperative infection, higher levels (>300 pg/mL) were observed 1 week after surgery. CONCLUSION: In patients after spinal surgery without infectious complications, blood levels of PSEP may immediately increase and return to preoperative levels 1 week after surgery. The PSEP value of 300 pg/mL 1 week after surgery might be used as a novel indicator for suspected SSI. LEVEL OF EVIDENCE: 4.

Lumbar artery injury from which the Adamkiewicz artery originated associated with lumbar spine injury: successfully treated by transcatheter arterial embolization.

PURPOSE: Lumbar artery injury associated with lumbar spine injury can be a cause of shock leading to life-threatening condition. The Adamkiewicz artery often bifurcates from a lumbar spine or an intercostal artery at the thoracolumbar junction, where spine injury most commonly occurs. However, in emergency transcatheter arterial embolization for lumbar artery injury, hemostasis has priority and blood supply to the Adamkiewicz artery is not frequently confirmed. The aim of this report is to present the case of lumbar spine injury with lumbar artery injury from which the Adamkiewicz artery bifurcated. METHODS: Retrospective description of a case. RESULTS: A 58-year-old man was pinned under about 300-kg steel container that fell on his back. He was transported to our hospital presented with hemorrhagic shock. Contrast-enhanced computed tomography demonstrated L1-2 flexion-distraction injury and the left psoas major muscle swelling with extravasation of contrast medium, which suspected lumbar artery injury. Emergency angiography demonstrated the bilateral 2nd lumbar artery injury. Likewise, the Adamkiewicz artery originated from the distal part of the left 2nd lumbar artery. Fortunately, selective angiography of the left 1st lumbar artery depicted collateral circulation to the Adamkiewicz artery. Embolization of the bilateral 2nd lumbar artery was performed and massive hemorrhage was controlled successfully without spinal cord ischemia. CONCLUSIONS: Close attention must be paid to lumbar artery injury in the management of patients with lumbar spine injury. Once lumbar artery injury is found, transcatheter arterial embolization can be the choice of the treatment with careful attention to the Adamkiewicz artery.

Right-sided infective endocarditis as a potentially fatal complication in patients with long-term refractory severe bradyarrhythmia after cervical spinal cord injury: A case report.

Bradyarrhythmia is usually a spontaneously subsiding complication of cervical spinal cord injury. However, in severe cases, it can lead to cardiac arrest. We report a case of cervical spinal cord injury, complicated by right-sided infective endocarditis after the placement of a temporary pacing catheter in the right ventricle for severe bradyarrhythmia that led to cardiac arrest. Although the patient׳s condition was successfully treated by pacing catheter removal and pharmacological therapy, right-sided infective endocarditis would be a fatal complication in cases of cervical spinal cord injury where cardiac pacing is required for long-term refractory severe bradyarrhythmia.

Efficacy of a high FFP:PRBC transfusion ratio on the survival of severely injured patients: a retrospective study in a single tertiary emergency center in Japan.

PURPOSE: Recent studies have shown increased survival benefits when a high fresh frozen plasma (FFP) to packed red blood cell (PRBC) ratio is used during trauma resuscitation. However, some reports have raised questions about the effect of higher FFP:PRBC transfusion ratios. The aim of this study was to examine the efficacy of high FFP:PRBC ratios in injured patients with regard to survival and morbidity in a single tertiary emergency center in Japan. METHODS: This study examined severe trauma patients who received 10 or more PRBC units during the first 24 h of admission. We examined the relationship between the FFP:PRBC ratios during the first 6 h and the patient outcome. RESULTS: The severity was similar among all groups. The mortality rate was 44.4% in the high (>1:1.5), 16.7% in the middle (1:1.5-1:2) and 33.3% in the low (<1:2) F:P ratio groups. Only one patient in the high group developed sepsis, and none of the patients developed ARDS. CONCLUSIONS: The current results indicate that the FFP:PRBC ratios during the first 6 h after admission might not affect the mortality or morbidity. However, differences between trauma care systems in Japan and other countries, along with other study limitations, necessitate that a subsequent prospective multicenter study be undertaken before any definitive conclusions can be made.

Atypical findings on magnetic resonance imaging in the patients with active pyogenic spondylitis in Japanese university hospitals.

Recently, aging population and immuno-compromised patients have been rising in Japan. Accordingly, patients with pyogenic spondylitis have been increasing and may present atypical clinical features. University hospitals treat many elderly patients and patients with poor general condition. Therefore, patients with pyogenic spondylitis treated at two university hospitals were retrospectively investigated to clarify the recent clinical and radiologic characteristics of this infection. There were 30 patients (average age: 68 years) treated in two university hospitals between 2009 and 2010. The onset was acute or subacute in 15 patients, insidious in 7 and unclassified in 8. Culture tests were performed in 25 patients, and the causative microorganisms were identified in 20 patients with the identification rate of 80%, including 4 patients infected by methicillin-resistant staphylococci. Classically, active pyogenic spondylitis is characterized by typical findings on magnetic resonance imaging (MRI): obvious signal decrease in T1-weighted image (WI) and increase in T2WI with contrast enhancement found in most of the bodies of two adjacent vertebrae and the intervening intervertebral disc. Among 29 patients with active pyogenic spondylitis, whose lesions were not in the healing stage, 16 patients demonstrated at least one of the atypical MRI findings; 9 patients showed involvement ≥ 3 vertebrae or only 1 vertebra, 5 showed the signal changes of the lesions involving small, spotty, or faint areas, and 3 showed small vertebral lesions but larger epidural or paraspinal abscesses. In conclusion, currently, about half of the patients with pyogenic spondylitis demonstrate atypical MRI findings in the university hospitals in Japan.

Oxygen free radical and antioxidant status in necrotizing soft tissue infection of the lower extremity; a report of two cases with opposite outcomes.

Two cases of necrotizing soft tissue infection of the lower extremity were treated concurrently but independently. Multimodal therapy including hip joint disarticulation and hyperbaric oxygen therapy was administered, resulting in opposite outcomes: survival and death. Analysis of the relationships between patient outcome and time-course changes in serum diacron-reactive oxygen metabolites (d-ROMs; an index of oxidative stress), antioxidative potential, and cytokines revealed that serum d-ROMs levels decreased with time, but high serum levels of interleukin-10 (anti-inflammatory cytokine) persisted in the patient who died. These findings may reflect an immunosuppressive status unfavorable to infection prevention. Serum d-ROMs may be a prognostic predictor in necrotizing soft tissue infections.

Natural history of intradural-extramedullary spinal cord tumors.

The objective of the present study was to investigate the natural history of intradural-extramedullary spinal cord tumors. Nine cases of intradural-extramedullary tumors were observed over the 2 years. The physical and magnetic resonance imaging (MRI) examination were performed in the first examination and every other year. Tumors were classified as the schwannoma type and the meningioma type based on the MRI findings. The tumor volume was calculated by the craniocaudal length on a sagittal image and maximum transverse diameter on an axial image of MRI, every year. The annual growth rate, which was defined as the change in the volume each year compared to the volume of the previous year, was examined. There were six cases in the schwannoma type and three cases in the meningioma type. The schwannoma type tumors presented several growth patterns: unchanging, continuous slight growth, and initial slight growth followed by rapid growth during the observation period (6.7 ± 2.7 years), while the meningioma type tumors presented the continuous growth pattern during the observation period (4.3 ± 2.5 years). The average annual growth rate was 2.3 ± 5.5% in the schwannoma type and 7.0 ± 8.5% in the meningioma type. Schwannoma type tumors showed relatively less change in their size and would be observed for a longer time.

Bilateral spondylolysis of inferior articular processes of the fourth lumbar vertebra: a case report.

Lumbar spondylolysis, a well known cause of low back pain, usually affects the pars interarticularis of a lower lumbar vertebra and rarely involves the articular processes. We report a rare case of bilateral spondylolysis of inferior articular processes of L4 vertebra that caused spinal canal stenosis with a significant segmental instability at L4/5 and scoliosis. A 31-year-old male who had suffered from low back pain since he was a teenager presented with numbness of the right lower leg and scoliosis. Plain X-rays revealed bilateral spondylolysis of inferior articular processes of L4, anterolisthesis of the L4 vertebral body, and right lateral wedging of the L4/5 disc with compensatory scoliosis in the cephalad portion of the spine. MR images revealed spinal canal stenosis at the L4/5 disc level. Posterior lumbar interbody fusion of the L4/5 was performed, and his symptoms were relieved.

Cervical myelopathy due to degenerative spondylolisthesis.

OBJECTIVE: To investigate clinical-radiological features of cervical myelopathy due to degenerative spondylolisthesis (DSL). METHODS: A total of 448 patients were operated for cervical myelopathy at Nishitaga National Hospital between 2000 and 2003. Of these patients, DSL at the symptomatic disc level was observed in 22 (4.9%) patients. Clinical features were investigated by medical records, and radiological features were investigated by radiographs. RESULTS: Disc levels of DSL were C3/4 in 6 cases and C4/5 in 16 cases. Distance of anterior slippage was 2 to 5 mm (average 2.9 mm) in flexion position. Space available for the spinal cord (SAC) was 11 to 15 mm (average 12.8 mm) in flexion position and 11 to 18 mm (average 14.6 mm) in extension position; 11 cases were reducible and 11 cases were irreducible in extension position. Myelograms demonstrated compression of spinal cord by the ligamentum flavum in extension position. Compression of spinal cord was not demonstrated in flexion position. C5-7 lordosis angle was lower than control. C5-7 range of motion (ROM) was reduced compared to controls. These alterations were statistically significant. CONCLUSIONS: DSL occurs in the mid-cervical spine. Lower cervical spine demonstrated restricted ROM and lower lordosis angle. Pathogenesis of cervical myelopathy due to DSL is compression of spinal cord by the ligamentum flavum in extension position and not by reduced SAC in flexion position.

Lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis.

STUDY DESIGN: Case-series study. OBJECTIVE: To describe the clinical presentation, characteristic findings of imaging studies, and treatment of lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis. BACKGROUND. Lumbar lesions in rheumatoid arthritis are relatively rare, with a limited number of systemic reports. METHODS: Six patients with lumbar radiculopathy caused by foraminal stenosis in rheumatoid arthritis were treated. The patients were all women with a mean age of 69 years and mean rheumatoid arthritis duration of 15 years. The medical records and imaging studies of all patients were reviewed. RESULTS: The affected nerve roots were L4 in four patients and L3 in two patients. Foraminal stenosis was not demonstrated in magnetic resonance images in four of the six patients. Selective radiculography with nerve root block reproduced pain, manifested blocking effect, and demonstrated compression of the nerve root by the superior articular process of the lower vertebra in all patients. Conservative treatment was performed on one patient, and surgery was conducted for the rest of the five patients; radiculopathy was improved in all patients. CONCLUSIONS: Lumbar foraminal stenosis is a characteristic pathology of rheumatoid arthritis, and should be kept in mind in the diagnosis of lumbar radiculopathy. Selective radiculography is useful in the diagnosis of affected nerve roots.

Anterior decompression and fusion versus laminoplasty for cervical myelopathy caused by soft disc herniation: a prospective multicenter study.

BACKGROUND: Anterior decompression and fusion (ADF) has conventionally been used, with stable outcomes, for cervical myelopathy caused by soft disc herniation. However, complications related to bone grafting and recurrence of myelopathy due to adjacent segment degeneration are its drawbacks. The efficacy of laminoplasty as an alternative has been sporadically reported, but no prospective study has been conducted to verify it. The purpose of this study was to determine whether laminoplasty is comparable for this condition. METHODS: Patients with cervical myelopathy caused by soft disc herniation whose preoperative disease period was less than 1 year were studied. The first 30 patients and the next 30 patients were treated by ADF and laminoplasty, respectively. All patients were given the same postoperative management. The outcomes were compared between the ADF and the laminoplasty groups consisting of 25 patients each who completed a follow-up examination 1 year after surgery. RESULTS: The two groups were found statistically matched regarding age at surgery, sex, disc level of herniation, anteroposterior diameter of the spinal canal, preoperative severity of myelopathy, cervical lordosis angle, and cervical range of motion (ROM). There was no statistically significant difference in the postoperative severity or recovery rate of myelopathy between the two groups. The amount of blood loss during surgery was significantly less in the laminoplasty group. Donor site pain and neck pain was minimal in all patients. Cervical lordosis angle and ROM were diminished postoperatively without a significant difference between the two groups. CONCLUSIONS: There was no critical difference between the ADF and laminoplasty groups with regard to neurological recovery and other surgery-related factors 1 year after surgery. Laminoplasty can be employed for cervical myelopathy caused by soft disc herniation in particular combined with multilevel spinal canal stenosis to avoid secondary myelopathy.