Spinal Subdural Hematoma Migration From a Cranial Subdural Hematoma: Two Case Reports and Literature Review.

Spinal subdural hematoma (SSDH) associated with cranial subdural hematoma (CSDH) is considered extremely rare and the etiology remains unclear. Herein, we report two cases of spontaneous SSDH concomitant with CSDH, with no history of trauma. First, a healthy 35-year-old woman suffered from left leg pain following a headache caused by acute CSDH. Magnetic resonance imaging (MRI) of the lumbar spine showed SSDH extending from the L5 to S2 vertebral levels. The leg symptoms were gradually relieved with conservative treatments within two weeks after onset. The SSDH was completely resolved six months after onset on MRI evaluations. Next, a 69-year-old woman developed a headache and right hemiparesis. Brain computed tomography (CT) demonstrated chronic left-sided CSDH and she underwent a single burr-hole craniotomy. Three weeks after surgery, she experienced difficulty walking because of severe leg pain caused by SSDH extending from the L3 to S1. The clinical symptoms were completely resolved with conservative treatment within one month after onset. At 3 months follow-up, SSDH disappeared on MRI evaluation. Herein, we presented two cases of SSDH associated with CSDH. In both cases, the leg symptoms of SSDH developed following the onset of CSDH. Given that both patients remained active during the interval between CSDH onset and the appearance of SSDH symptoms, the SSDH was likely caused by migration of the CSDH contents to the lumbar spine because of gravity.

Predictors for clinical outcomes of tubular surgery for endoscopic decompression in selected patients with lumbar spinal stenosis.

INTRODUCTION: The success rate of decompression surgery for lumbar spinal stenosis (LSS) has been reported to vary from 60 to 80%. The purpose of this study was to analyze the predictors for clinical outcomes after tubular surgery for endoscopic decompression (microendoscopic decompression) for LSS. MATERIALS AND METHODS: A total of 100 patients with degenerative LSS (M/F: 61/39, Age: mean 69.7 years), who underwent microendoscopic decompression and had a minimum 2-year follow-up (FU) after surgery, were reviewed. All patients suffered from leg-related symptoms predominantly without severe mechanical back pain, preoperatively. The presence of chronic arterial occlusion of the lower limbs was ruled out. The primary outcome measure was clinical evaluation at 2-year FU using the Oswestry Disability Index (ODI). Furthermore, numeric rating scales, Japanese Orthopedic Association (JOA) lumbar score and JOA Back Pain Evaluation Questionnaire were used for secondary outcome measures. Based on findings of univariable analyses, multivariable logistic regression analysis was applied to identify preoperative predictors for the clinical outcomes. RESULTS: Sixty-eight patients (68%) were assessed as good outcomes, on the basis of minimum clinically important difference of the ODI (13 points ≤) and final ODI score (< 30 points). The secondary outcomes were further support for the primary outcome. In multivariable logistic regression analysis, co-existence of intradiscal vacuum phenomenon with LSS (odds ratio [OR] 8.26; 95% confidence interval [95% CI] 2.32-29.34; p = 0.001) and ischemic cardiovascular comorbidities (OR, 13.3; 95% CI, 1.9-92.57; p = 0.009) were significantly associated with poor clinical outcomes. CONCLUSIONS: We found co-existence of intradiscal vacuum phenomenon with LSS and ischemic cardiovascular comorbidity to be preoperative predictors of less favorable clinical outcomes after microendoscopic decompression in selected patients of LSS. Although the conclusion obtained from restricted state, the information would be able to help in patient selection of the tubular surgery for endoscopic decompression for LSS.

Predictive factors of non-treatment and non-persistence to osteoporosis medication after fragility hip fractures at 3 years after discharge: a multicentre, prospective cohort study in the northern Kyushu district of Japan.

We examined osteoporosis medication use and factors affecting persistence in 497 patients with fragility hip fractures. Only 25.5% of patients received continuous medication for 3 years, and 44.1% of patients received no treatment. Low Barthel index at discharge was a risk factor for both non-treatment and non-persistence to osteoporosis medication. PURPOSE: Fragility hip fractures (FHF) caused by osteoporosis decrease the quality of life and worsen life expectancy. Use of osteoporosis medication may be an efficient method in the prevention of secondary FHF. However, previous studies have reported low rates of osteoporosis medication and persistence after FHF. This study aimed to evaluate osteoporosis medication use and factors affecting persistence in patients with FHF in the northern Kyushu area of Japan. METHODS: A total of 497 FHF patients aged ≥ 60 years with a 3-year follow-up were included. We prospectively collected data from questionnaires sent every 6 months regarding compliance with osteoporosis medication. We compared baseline characteristics among three groups: no treatment (NT), no persistence (NP), and persistence (P), and conducted multivariable regression models to determine covariates associated with non-treatment (NT vs. NP/P) and non-persistence (NP vs. P). RESULTS: There were 219 (44.1%), 151 (30.4%), and 127 (25.5%) patients in the NT, NP, and P groups, respectively. Factors associated with non-treatment were male sex, chronic kidney disease, no previous osteoporosis treatment, and low Barthel index (BI) at discharge. The only factor associated with non-persistence was a low BI at discharge. Factors associated with a low BI at discharge were male sex, older age, trochanteric fracture, and surgical delay. CONCLUSION: Low BI at discharge is a risk factor for both non-treatment and non-persistence to osteoporosis medication. Therefore, appropriate interventions to improve BI may result in persistence to osteoporosis medication.

＜Editors' Choice＞ Treatment strategy for upper cervical epidural abscess: a literature review.

We aimed to determine available evidences in the literature regarding surgical approaches and methods, timing of surgical interventions, duration of perioperative antibiotics, and duration of nonsurgical treatments (antibiotics administration) in patients with upper cervical (occiput-C2) epidural abscess (UCEA). We performed a literature review of the articles on surgical interventions and antibiotic therapy to treat UCEA, searching the PubMed database for relevant articles published in the English language (as of March 2020). In total, 53 patients with UCEA were identified. Permanent limb paralysis or death was observed in 1/15 (6.7%) patients who received the transoral approach and 2/15 (13.3%) patients who received the transcervical approach, 1/26 (3.8%) patients who underwent surgery before the onset of paralysis, and 2/4 (50.0%) patients who underwent surgery after the onset of paralysis. In 85%-89% of cases, antibiotic administration was continued for 6-12 weeks, which was determined by the confirmation of reduced inflammatory response and/or abscess disappearance on imaging. Differences in surgical approaches may not be associated with the incidence of permanent limb paralysis or death. Surgical interventions before limb paralysis onset are recommended in UCEA patients. In perioperative and nonoperative treatments, antibiotic administration for 6-12 weeks may be supported based on the confirmation of reduced inflammatory response and/or abscess disappearance on imaging. Further investigations are needed.

Occipital bone erosion induced by C1 pedicle screw as a late complication of atlantoaxial fixation: a case report and literature review.

PURPOSE: The objective of this case report is to highlight occipital bone erosion as an unusual late complication of C1-C2 instrumented fixation. CASE PRESENTATION: A 60-year-old man of a displaced Anderson type II odontoid fracture was surgically treated by C1-C2 pedicle screw fixation. Occipital bone erosions, caused by a repeat irritation of the end of rod to the occipital bone, were detected on multiplane reconstructed computed tomography at 3 months after surgery. The lesion progressed over time with increasing the C2 anteversion on radiological evaluations. Eventually, the bony shell had been reactively formed around the protruded screw-rod construct and the Oc-C1 segment had been spontaneously stabilized. Fortunately, he had experienced no symptoms caused by the lesion at 5-year follow-up. CONCLUSION: The occipital bone erosion is an unusual late complication in C1-C2 posterior fixation using C1 pedicle screw. The increasing occipital-C1 lordosis compensating for the great C2 anteversion (high C2 slope) was related to the progression of the lesion. In C1-C2 pedicle screw fixation, surgeons should recognize a possibility of this complication and realize a relation between the occurrence of the lesion and the sagittal alignment of the cervical spine to take measures to avoid the complication.

Radiographic and Clinical Results of C1 Laminoplasty for the Treatment of Compressive Myelopathy.

STUDY DESIGN: Case series. PURPOSE: To evaluate the radiographic and clinical results of C1 laminoplasty without fusion. OVERVIEW OF LITERATURE: C1 laminectomy has been the standard procedure for decompression at the C1 level. However, there have been some reports of trouble cases after C1 laminectomy. C1 laminoplasty might be superior to C1 laminectomy with regard to maintaining the original C1 anatomical shape, preventing compression from the posterior soft tissue, and ensuring an adequate bonegrafting site around the C1 posterior part if additional salvage fusion surgery is necessary afterward. METHODS: Seven patients with spinal cord compression without obvious segmental instability at the C1/2 level treated by C1 laminoplasty were included. The indication of C1 laminoplasty was same as that of C1 laminectomy. C1 laminoplasty was performed in the same way as subaxial double-door laminoplasty. The imaging findings were evaluated using X-ray, computed tomography, and magnetic resonance imaging. The clinical results were evaluated using the Japanese Orthopaedic Association (JOA) Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) and JOA score. Peri- and postoperative complications were also investigated. RESULTS: No patient showed increased C1/2 segmental instability after the surgery. The mean pre- and postoperative JOA scores were 8.6 and 11.7, respectively. The mean recovery rate was 40.2%. The effective rate in the JOACMEQ was 50% for the cervical spine function, 33% for the upper extremity function, 50% for the lower extremity function, 17% for the bladder function, and 17% for the quality of life. No major complication that seemed to be unique to C1 laminoplasty was observed over a period of about 4 years follow-up. CONCLUSIONS: C1 laminoplasty for patients without obvious segmental instability might be a viable alternative procedure to C1 laminectomy.

Is a Fracture of the Transverse Process of L5 an Indicator of the Presence and/or Severity of a Pelvic Fracture?

INTRODUCTION: A transverse process of L5 (L5TP) fracture may be associated with the presence and/or severity of a pelvic fracture. However, there is little evidence to support this view. The purpose of this study was to investigate the relationship between L5 TP fracture and the presence and/or severity of a pelvic fracture on radiograph and CT. METHODS: A total of 146 patients (82 women and 64 men; age range, 5-97 years) who were treated for pelvic fractures were evaluated. The site of pelvic fractures, presence of an L5 TP fracture with radiograph and CT, associated injuries and the need for blood transfusion, surgical intervention, and mortality were investigated retrospectively. According to the Burgess and Young classification, there were 42 unstable fractures. For each parameter, correlations between the parameters were evaluated using a chi-squared test and a logistic regression analysis. A p-value <0.05 was considered to be statistically significant. RESULTS: The sensitivity of L5 TP fractures on radiograph and CT were 51% and 95%, respectively (p < 0.0001). Multiple logistic regression analysis revealed that, of the L5 TP fractures patients on radiograph, the odds ratios for sacral fractures were 4.5 (95% confident interval [CI], 1.1-17.9); based on CT, the odds ratios for sacral fractures and the need for blood transfusion were 18.2 (95%CI, 5.1-64.9) and 3.2 (95%CI, 1.1-9.1), respectively. CONCLUSIONS: This study demonstrated that L5 TP fractures on radiograph and/or CT could indicate a high risk of sacral fracture and need for blood transfusion. When an L5TP fracture is diagnosed on initial radiograph or CT in the emergency setting, it is necessary to conduct further investigations for pelvic ring fractures and to alert the attending staff to the high-risk fracture.

Predictive factors of mortality of patients with fragility hip fractures at 1 year after discharge: A multicenter, retrospective study in the northern Kyushu district of Japan.

PURPOSE: Fragility hip fractures (FHFs) are associated with a high risk of mortality, but the relative contribution of various factors remains controversial. This study aimed to evaluate predictive factors of mortality at 1 year after discharge in Japan. METHODS: A total of 497 patients aged 60 years or older who sustained FHFs during follow-up were included in this study. Expected variables were finally assessed using multivariable Cox proportional hazards models. RESULTS: The 1-year mortality rate was 9.1% (95% confidence interval: 6.8-12.0%, n = 45). Log-rank test revealed that previous fractures (p = 0.003), Barthel index (BI) at discharge (p = 0.011), and place-to-discharge (p = 0.004) were significantly associated with mortality for male patients. Meanwhile, body mass index (BMI; p = 0.023), total Charlson comorbidity index (TCCI; p = 0.005), smoking (p = 0.007), length of hospital stay (LOS; p = 0.009), and BI (p = 0.004) were the counterparts for females. By multivariate analyses, previous vertebral fractures (hazard ratio (HR) 3.33; p = 0.044), and BI <30 (HR 5.42, p = 0.013) were the predictive variables of mortality for male patients. BMI <18.5 kg/m2 (HR 2.70, p = 0.023), TCCI ≥5 (HR 2.61, p = 0.032), smoking history (HR 3.59, p = 0.018), LOS <14 days (HR 13.9; p = 0.007), and BI <30 (HR 2.76; p = 0.049) were the counterparts for females. CONCLUSIONS: Previous vertebral fractures and BI <30 were the predictive variables of mortality for male patients, and BMI <18.5 kg/m2, TCCI ≥5, smoking history, LOS <14 days, and BI <30 were those for females. Decreased BI is one of the independent and preventable risk factors. A comprehensive therapeutic approach should be considered to prevent deterioration of activities of daily living and a higher risk of mortality.

Surgical Outcomes of Minimally Invasive Stabilization for Spinal Fractures in Patients with Ankylosing Spinal Disorders.

STUDY DESIGN: A retrospective study. PURPOSE: To evaluate the clinical and radiological outcomes of ankylosing spinal disorder (ASD) patients with spinal fractures treated by minimally invasive stabilization (MISt) using percutaneous pedicle screws (PPSs). OVERVIEW OF LITERATURE: ASDs, such as ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH), increase susceptibility to spinal fractures because of extremely decreased spinal flexibility. Such fractures tend to be unstable and, consequently, should be treated with multiple-segmental internal fixation. However, conventional internal fixation procedures can severely damage the soft tissue, resulting in severe hemorrhage. Therefore, MISt is the preferred approach to treat spinal fractures in ASD patients. METHODS: Nine ASD patients (four males and five females; three AS and six DISH patients) with spinal fractures who were treated by MISt using PPSs, were reviewed from April 2009 to August 2016. One patient died of aspiration pneumonia during follow-up (FU), and the remaining eight patients underwent clinical and radiological evaluation. RESULTS: The mean age at surgery was 79.6 years (range, 68-95 years). The mean duration of postoperative FU was 14.2 months (range, 3-30 months). All treated fractures were anterior and posterior element injuries with distraction. Three patients presented delayed onset preoperative neurological deficit following trauma. The mean operation time was 179.6 minutes (range, 92-340 minutes). The mean hemorrhage was 103.6 mL (range, unquantifiable to 480 mL). Radiological evaluations at FU showed preservation of the acceptable postoperative correction of the fractured vertebra, as there were no re-collapses of the fractured vertebrae during FU. CONCLUSIONS: ASD patients must be acknowledged as highly susceptible to unstable spinal fractures, even after relatively mild trauma. MISt using PPSs may be an effective treatment for spinal fractures in such patients.

Minimally Invasive Transtubular Endoscopic Decompression for L5 Radiculopathy Induced by Lumbosacral Extraforaminal Lesions.

STUDY DESIGN: Retrospective study. PURPOSE: This study aimed to evaluate the efficacy of minimally invasive transtubular endoscopic decompression for the treatment of lumbosacral extraforaminal lesion (LSEFL). OVERVIEW OF LITERATURE: Conventional procedures for surgical decompression for the treatment of LSEFL involve certain technical challenges because the lumbosacral extraforaminal region has unique anatomical features. Moreover, the efficacy of minimally invasive procedures performed via the posterolateral approach for LSEFL has been reported. METHODS: Twenty-five patients who had undergone minimally invasive transtubular endoscopic decompression for the treatment of LSEFL and could be followed up for at least 1 year postoperatively were enrolled. Five of these patients had a history of lumbar surgery, and seven had concomitant adjacent-level spinal stenosis. The clinical outcomes were evaluated using the Japanese Orthopaedic Association (JOA) lumbar score, numeric rating scale (NRS), and the JOA Back Pain Evaluation Questionnaire (JOABPEQ). The mean postoperative follow-up (FU) duration was 3.8 years. RESULTS: All procedures could be completed without any severe surgical complications, and all patients could resume their previous activity level within 1 month postoperatively. The JOA score significantly increased from 14.1±4.0 at baseline to 23.1±3.7 at the 1-year FU and 22.1±3.8 at the last FU. Similarly, there were significant improvements in the postoperative NRS and JOABPEQ scores. An additional surgery was performed in two patients (8%) during the FU period. Patients with degenerative scoliosis exhibited significantly poorer outcomes compared with those without this condition. CONCLUSIONS: Transtubular endoscopic decompression can overcome certain technical challenges involved in the conventional procedures for LSEFL treatment; therefore, it can be recommended as a useful procedure for treating LSEFL. This procedure can provide some benefits to LSEFL patients and offer a well-illuminated surgical field and high surgical safety for the surgeon. However, the procedure should be carefully adapted for LSEFL patients with concomitant degenerative scoliosis.

Characteristics of patients with fragility hip fractures in the northern Kyushu district in Japan: a multicenter prospective registry based on an electronic data capture system.

Osteoporosis has become a worldwide public health problem, in part due to the fact that it increases the risk of fragility hip fractures (FHFs). The epidemiological assessment of FHFs is critical for their prevention; however, datasets for FHFs in Japan remain scarce. This was a multicenter, prospective, observational study in the northern district of Kyushu Island. Inclusion criteria were age > 60 years with a diagnosis of FHF and acquisition of clinical data by an electronic data capture system. Of 1294 registered patients, 1146 enrolled in the study. Nearly one third of patients (31.8%) had a history of previous fragility fractures. The percentage of patients receiving osteoporosis treatment on admission was 21.5%. Almost all patients underwent surgical treatment (99.1%), though fewer than 30% had surgery within 48 h after hospitalization. Bone mineral density (BMD) was evaluated during hospitalization in only 50.4% of patients. The rate of osteoporosis treatment increased from 21.5% on admission to 39.3% during hospitalization. The main reasons that prescribers did not administer osteoporosis treatment during hospitalization were forgetfulness (28.4%) and clinical judgment (13.6%). Age and female ratio were significantly higher in patients with previous FHFs than in those without. There was a significant difference in the rate of osteoporosis treatment or L-spine BMD values in patients with or without previous FHFs on admission. In conclusion, this study confirmed that the evaluation and treatment of osteoporosis and FHFs is still suboptimal in Japan, even in urban districts.

Does Modic Change Progresss With Age?

STUDY DESIGN: Cross-sectional imaging study. OBJECTIVE: The aim of this study was to clarify the trend in the generation distinctions about the prevalence of Modic change (MC) including elderly patients. SUMMARY OF BACKGROUND DATA: MC has been discussed regarding its clinical significance, relationship with low back pain, suitable treatments, prevalence, and natural history. However, previous reports have focused on younger subjects, with few studies conducted in elderly patients. If MC is actually a progressive condition of a patient, then it should become more common as the patient ages. We herein report the distribution of MC across several age groups. METHODS: Patients who underwent lumbar magnetic resonance imaging (MRI) in our institution from April 2013 to March 2015 were recruited. MC was assessed using T1- and T2-weighted magnetic resonance imaging (MRI) and divided into Modic types (MT) 1, 2, and 3, and mixed type. Trends in the prevalence of MC were analyzed based on age. RESULTS: We ultimately included 585 patients of an initial 937 who underwent lumbar MRI. The mean age was 65 years. MC was identified in 36.0% of the patients. The prevalence of MC by age was 0% for those in their 10 s, 10% for those in their 20 s, 33% for those in their 30 s, 27% for those in their 40 s, 32% for those in their 50 s, 44% for those in their 60 s, 42% for those in their 70 s, and 26% for those in their 80 s. By type, 3.3% were MT1, 81.3% were MT2, 0.5% were MT3, and 14.8% were mixed type. CONCLUSION: The prevalence of MC increased with age to some degree, with the highest frequency observed in individuals in their 60 s before declining in those in their 70 s and 80 s. These findings suggest that MC might not simply progress with age, particularly after the seventh decade of life. LEVEL OF EVIDENCE: 4.

Characterization and Risk Factor Analysis for Recurrence Following Microendoscopic Diskectomy for Lumbar Disk Herniation.

Background and Study Aims Microendoscopic diskectomy (MED) has become an established minimally invasive procedure in surgical treatment for lumbar disk herniation (LDH). LDH recurrence following surgery is also an important problem in MED because the risk of LDH recurrence may surpass the advantages of MED. The purpose of this study was to investigate the characteristics of recurrence following MED for LDH and identify the risk factors for a recurrence. Materials and Methods A total of 163 patients who underwent MED for LDH and could be followed for a minimum of 1 year after surgery were enrolled in this study (follow-up [FU] rate: 79.9%). We investigated the characteristics of LDH recurrence and conducted a comparative study between the patient groups with and without recurrence to identify the risk factors for the recurrence. Results The recurrence of LDH was observed in 19 patients (11.7%) during a mean of 38 months FU. Although the mean length of time from MED to recurrence was 19.2 months, 36.8% of the LDH recurrence occurred in the first 3 months following MED. Eleven patients were treated successfully by conservative treatments, and the remaining eight patients had to undergo revision surgery (MED in five patients, microdiskectomy in one, and instrumented fusion in two). In the analysis of risk factors for the recurrence, the presence of diabetes mellitus (DM) was significantly correlated with the recurrence (p = 0.0027). Conclusions The recurrence rate following MED for LDH was equivalent to those of previous reports of conventional and microscopic diskectomy. However, a third of the LDH recurrences occurred in the first 3 months after MED. We should pay attention to LDH recurrence at an early phase following MED and recognize the presence of DM as a risk factor for LDH recurrence.

Clinical and Radiological Study Focused on Relief of Low Back Pain After Decompression Surgery in Selected Patients With Lumbar Spinal Stenosis Associated With Grade I Degenerative Spondylolisthesis.

STUDY DESIGN: A retrospective study. OBJECTIVE: The aim of the present study was to identify the clinical and radiological features of low back pain (LBP) that was relieved after decompression alone of lumbar spinal stenosis (LSS) associated with grade I lumbar degenerative spondylolisthesis (LDS). SUMMARY OF BACKGROUND DATA: Although decompression and fusion are generally the recommended surgical treatments of LDS, several authors have reported that some patients with LDS could obtain good clinical results including relief from LBP by decompression alone. The pathogenesis of relief from LBP after decompression is, however, not known. METHODS: Forty patients with LSS associated with grade I LDS, who underwent a minimally invasive surgical-decompression were enrolled in the present study. All patients complained preoperatively of predominantly leg-related symptoms and LBP (≥ 4 points on Numeric Rating Scale). Clinical and radiological assessments were performed 1 year after surgery (a relief of LBP: Numeric Rating Scale reduction ≥3 points and valuation ≤3 points) and at the last follow-up. We conducted a comparative study between patient groups with and without the relief from LBP (groups R and N, respectively). RESULTS: Twenty-nine patients were distributed to group R and the remaining 11 patients to group N. Preoperatively, there was a significant difference between the two groups for age and radiographic flexibility for lumbar extension. Postoperatively, there was a positive correlation between improvement in both LBP and leg symptoms. The clinical outcomes of group R were significantly better than those of group N throughout follow-up period (mean 37 mo). In group R, sagittal lumbopelvic radiographic parameters improved significantly after surgery. CONCLUSION: Although the causes of LBP are varied in each patients, our results show that concomitant LSS itself might cause LBP in some patients with grade I LDS, because it involves impingement of the neural tissue and discordant sagittal lumbopelvic alignment. LEVEL OF EVIDENCE: 3.

Accuracy of pedicle screw insertion in the thoracic and lumbar spine: a comparative study between percutaneous screw insertion and conventional open technique.

INTRODUCTION: In the last decade, posterior instrumented fusion using percutaneous pedicle screws (PPSs) had been growing in popularity, and its safety and good clinical results have been reported. However, there have been few previous reports of the accuracy of PPS placement compared with that of conventional open screw insertion in an institution. This study aimed to evaluate the accuracy of PPS placement compared with that of conventional open technique. MATERIALS AND METHODS: One hundred patients were treated with posterior instrumented fusion of the thoracic and lumbar spine from April 2008 to July 2013. Four cases of revised instrumentation surgery were excluded. In this study, the pedicle screws inserted below Th7 were investigated, therefore, a total of 455 screws were enrolled. Two hundred and ninety-three pedicle screws were conventional open-inserted screws (O-group) and 162 screws were PPSs (P-group). We conducted a comparative study about the accuracy of placement between the two groups. Postoperative computed tomography scans were carried out to all patients, and the pedicle screw position was assessed according to a scoring system described by Zdichavsky et al. (Eur J Trauma 30:241-247, 2004; Eur J Trauma 30:234-240, 2004) and a classification described by Wiesner et al. (Spine 24:1599-1603, 1999). RESULTS: Based on Zdichavsky's scoring system, the number of grade Ia screws was 283 (96.6 %) in the O-group and 153 (94.4 %) in the P-group, whereas 5 screws (1.7 %) in the O-group and one screw (0.6 %) in the P-group were grade IIIa/IIIb. Meanwhile, the pedicle wall penetrations based on Wiesner classification were demonstrated in 20 screws (6.8 %) in the O-group, and 12 screws (7.4 %) in the P-group. No neurologic complications were observed and no screws had to be replaced in both groups. CONCLUSIONS: The PPSs could be ideally inserted without complications. There were no statistically significant differences about the accuracy between the conventional open insertion and PPS placement.

Risk Factor Analysis for C5 Palsy after Double-Door Laminoplasty for Cervical Spondylotic Myelopathy.

STUDY DESIGN: A retrospective comparative study. PURPOSE: To clarify the risk factors related to the development of postoperative C5 palsy through radiological studies after cervical double-door laminoplasty (DDL). OVERVIEW OF LITERATURE: Although postoperative C5 palsy is generally considered to be the result of damage to the nerve root or segmental spinal cord, the associated pathology remains controversial. METHODS: A consecutive case series of 47 patients with cervical spondylotic myelopathy treated by DDL at our institution between April 2008 and April 2015 were reviewed. Postoperative C5 palsy occurred in 5 of 47 cases after DDL. We investigated 9 radiologic factors that have been reported to be risk factors for C5 palsy in various studies, and statistically examined these between the two groups of palsy and the non-palsy patients. RESULTS: We found a significant difference between patients with and without postoperative C5 palsy with regards to the posterior shift of spinal cord at C4/5 (p=0.008). The logistic regression analyses revealed posterior shift of the spinal cord at C4/5 (odds ratio, 12.066; p=0.029; 95% confidence interval, 1.295-112.378). For the other radiologic factors, there were no statistically significant differences between the two groups. CONCLUSIONS: In the present study, we showed a significant difference in the posterior shift of the spinal cord at C4/5 between the palsy and the non-palsy groups, indicating that the "tethering phenomenon" was likely a greater risk factor for postoperative C5 palsy.

Percutaneous Transpedicular Interbody Fusion Technique in Percutaneous Pedicle Screw Stabilization for Pseudoarthrosis Following Pyogenic Spondylitis.

This report introduces a percutaneous transpedicular interbody fusion (PTPIF) technique in posterior stabilization using percutaneous pedicle screws (PPSs). An 81-year-old man presented with pseudoarthrosis following pyogenic spondylitis 15 months before. Although no relapse of infection was found, he complained of obstinate low back pain and mild neurological symptoms. Radiological evaluations showed a pseudoarthrosis following pyogenic spondylitis at T11-12. Posterior stabilization using PPSs from Th9 to L2 and concomitant PTPIF using autologous iliac bone graft at T11-12 were performed. Low back pain and neurological symptoms were immediately improved after surgery. A solid interbody fusion at T11-12 was completed 9 months after surgery. The patient had no restriction of daily activity and could play golf at one year after surgery. PTPIF might be a useful option for perform segmental fusion in posterior stabilization using PPSs.

Spontaneous regression of posterior epidural migrated lumbar disc fragments: case series.

BACKGROUND CONTEXT: Posterior epidural migrated lumbar disc fragments is an extremely rare disorder. Surgical treatment was performed in all reported cases. To the best of our knowledge, there are no reported cases of the use of conservative treatment for posterior epidural migrated lumbar disc fragments. PURPOSE: To report the possibility of a spontaneous regression of posterior epidural migrated lumbar disc fragments. STUDY DESIGN: Case series. METHODS: Four patients with posterior epidural migrated lumbar disc fragments were treated at Karatsu Red Cross Hospital between April 2008 and August 2010. Spontaneous regression of the posterior epidural migrated lumbar disc fragments with relief of symptoms was observed on magnetic resonance imaging (MRI) in three cases. Another patient underwent surgical treatment. The present and previously reported cases of posterior epidural migrated lumbar disc fragments were analyzed with respect to patient age, imaging features on MRI, the level of the lesion, clinical symptoms, treatment, and outcomes. RESULTS: Conservative treatment was successful, and spontaneous lesion regression was seen on MRI with symptom relief in three cases. CONCLUSIONS: Although posterior epidural migrated lumbar disc fragment cases are generally treated surgically, the condition can regress spontaneously over time, as do sequestrated disc fragments. Spontaneous regression of lumbar disc herniations is a widely accepted observation at present. Posterior epidural migrated lumbar disc fragments fall under the sequestrated type of disc herniation. In fact, the course of treatment for posterior epidural migrated lumbar disc fragments should be determined based on the symptoms and examination findings, as in cases of ordinary herniation. However, providing early surgical treatment is important if the patient has acute cauda equina syndrome or the neurologic symptoms worsen over time.

Instability of the Vertebrae Remains following Balloon Kyphoplasty.

Study Design Retrospective cohort study. Objectives The mechanism underlying the pain relief observed following balloon kyphoplasty (BKP) to vertebral compression fractures is reported to involve stabilization of the fractured vertebrae. However, whether fixation of the vertebrae was achieved immediately after BKP has not been investigated. The purpose of this study was to assess fixation of the vertebrae immediately after BKP and whether the instability was related to visual analog scale (VAS) scores. Methods Thirty-eight patients with vertebrae that were evaluated on lateral roentgenkymography within 1 week after BKP were recruited. Instability was defined as a cleft observed between the cement and end plate of the vertebra in the supine position that disappeared in the sitting position, and the posterior wall height of the vertebra was reduced in the sitting position. Results Instability of the vertebrae immediately after BKP was observed in 17 cases. VAS scores improved in all cases, and no significant differences were observed with or without instability. Conclusions The mechanism of rapid pain relief following BKP was not strong fixation but some degree of stabilization or other factors. We suggest that more research is needed about the mechanism of pain relief following BKP in the future.