Dysgammaglobulinemia Associated With Glu349del, a Hypomorphic XIAP Mutation

BACKGROUND

X-linked lymphoproliferative syndrome type 2 is a rare hereditary immunodeficiency caused by mutations in the XIAP gene. This immunodeficiency frequently results in hemophagocytic lymphohistiocytosis, although hypogammaglobulinemia and dysgammaglobulinemia are also common.

OBJECTIVE

We identified 17 patients from 12 Japanese families with mutations in XIAP. The Glu349del mutation was observed in 3 patients, each from a different family. Interestingly, these patients exhibited dysgammaglobulinemia but not hemophagocytic lymphohistiocytosis. We conducted an immunological study of patients carrying Glu349del and other mutations to elucidate the pathogenic mechanisms of dysgammaglobulinemia in patients with mutations in the XIAP gene.

PATIENTS AND METHODS

We performed an immunological study of 2 patients carrying the Glu349del mutation and 8 patients with other mutations.

RESULTS

Flow cytometry showed that the percentage of memory B cells in patients with a mutation in XIAP was lower than that observed in the healthy controls. The patients with the Glu349del mutation had a lower percentage of memory B cells than those with other mutations. Ig production was reduced in patients with the Glu349del mutation. Increased susceptibility to apoptosis was observed in the patients with other mutations. Susceptibility to apoptosis was normal in patients with Glu349del. Microarray analysis indicated that expression of Ig-related genes was reduced in patients with the Glu349del mutation and that the pattern was different from that observed in the healthy controls or patients with other mutations in XIAP.

CONCLUSIONS

Patients carrying the Glu349del mutation in the XIAP gene may have a clinically and immunologically distinct phenotype from patients with other XIAP mutations. The Glu349del mutation may be associated with dysgammaglobulinemia.

Functional computed tomography scanning for evaluating fusion status after anterior cervical decompression fusion

INTRODUCTION

Nonunion is a major complication of anterior cervical fusion that causes poor outcomes and occasionally requires additional operative intervention. The purpose of this study is to evaluate the accuracy of functional computed tomography (CT) scanning for determining fusion status after anterior cervical fusion by comparing with functional radiographs.

MATERIALS AND METHODS

The fusion status in 59 patients treated by anterior cervical fusion was assessed by functional radiography and functional CT scanning at 6 and 12 months after surgery. Fusion rates and clinical symptoms were evaluated. Fusion on functional radiography was defined as less than 2 mm of motion between adjacent spinous processes and a particular bony trabeculation on functional CT; fusion was defined as nonexistence of a clear zone or a gas pattern and a particular bone connection on reconstructed sagittal-view images.

RESULTS

Functional radiographs demonstrated solid fusion in 83.9% at 6 months and 91.1% at 12 months postoperatively; functional CT showed solid fusion in 55.3 and 78.6%, respectively. The fusion rate detected on functional CT images was significantly lower than that on functional radiographs at each period. At 6 months postoperatively, patients with incomplete union on functional CT were more likely to have neck pain than those who had complete union on functional CT. (46.2 vs 13.3%, P < 0.05) CONCLUSION: Functional CT can detect nonunion more clearly than functional radiography. At 6 months postoperatively, patients with incomplete union on functional CT images were likely to have more neck pain. Functional CT may allow accurate detection of symptomatic nonunion after anterior cervical fusion.

Risk factors for poor outcome of cervical laminoplasty for cervical spondylotic myelopathy in patients with diabetes

BACKGROUND

Diabetes is one of the most frequent comorbidities in patients with cervical spondylotic myelopathy. The purpose of this study was to characterize the risk factors for poor treatment outcome following cervical laminoplasty for cervical spondylotic myelopathy in patients with diabetes.

METHODS

A total of 105 consecutive patients with diabetes and cervical spondylotic myelopathy who underwent double-door laminoplasty were included in this study; there were sixty-five male patients and forty female patients with a mean age of 68.2 years (range, forty-three to eighty-three years). All patients were followed for twelve months or more after surgery, with a mean follow-up time (and standard deviation) of 25.7 ± 14.2 months. All patients had palliative controlled blood glucose levels in the immediate term during the perioperative period. We evaluated the recovery rate on the basis of the Japanese Orthopaedic Association score. Logistic regression analyses (univariate analysis and multivariate analysis) were performed to identify the risk factors for poor outcome. Poor outcome was defined as a postoperative recovery rate of <50%, and good outcome was defined as a postoperative recovery rate of ≥ 50%.

RESULTS

Univariate logistic regression analysis showed that a patient age of sixty-five years or older (odds ratio, 3.111; p = 0.0085) and a duration of cervical spondylotic myelopathy symptoms for twelve months or more (odds ratio, 3.940; p = 0.0012) were associated with an increased risk of poor surgical outcome. High glycated hemoglobin levels of ≥ 6.5% (odds ratio, 2.591; p = 0.0193) and a duration of diabetes for ten years or more (odds ratio, 2.245; p = 0.0321) were significant risk factors for poor surgical outcome. Multivariate logistic regression analysis determined that glycated hemoglobin levels of ≥ 6.5% (odds ratio, 2.822; p = 0.0441) and a duration of diabetes for ten years or more (odds ratio, 2.240; p = 0.0410) were significant risk factors for poor treatment outcome. Fasting blood glucose levels did not affect treatment outcomes.

CONCLUSIONS

Diabetes with advanced age and long-term cervical spondylotic myelopathy symptoms adversely affected cervical laminoplasty outcomes. High preoperative glycated hemoglobin levels and long-term diabetes are risk factors for poor cervical laminoplasty outcomes in patients with diabetes and cervical spondylotic myelopathy.

Spinal cord cross-sectional area during flexion and extension in the patients with cervical ossification of posterior longitudinal ligament

PURPOSE

The pathomechanism of cervical myelopathy due to cervical ossification of posterior longitudinal ligament (C-OPLL) remains unclear. No previous literature has quantified the influence of dynamic factors on cervical myelopathy due to C-OPLL. The purpose was to investigate the influence of dynamic factors on the spinal column in the patients with C-OPLL using CT scan after myelography (MCT).

METHODS

The study included 41 patients with cervical myelopathy due to C-OPLL. An MCT was done during neck flexion and extension, and spinal cord cross-sectional areas (SCCSA) were measured at each disc level between C2/3 and C7/T1. Ossification morphology at each segment was divided into three groups, connection department, coating part, and non-connection department of OPLL group. Dynamic changes of SCCSA in each group of ossification morphology were calculated. The relationship between clinical results and SCCSA at the narrowest level was investigated.

RESULTS

MCT showed SCCSA changes during neck extension; 7.4 ± 5.1 mm(2) in the connection department, 5.8 ± 6.0 mm(2) in the coating part, and 6.7 ± 6.4 mm(2) in the non-connection department of OPLL group. There difference was not statistically significant. There was a weak correlation between the JOA score and SCCSA at the narrowest level (R = 0.49). There was no significant correlation between the recovery rate of JOA score and SCCSA at the narrowest level (R = 0.37).

CONCLUSION

Dynamic factors are seen both in cervical myelopathy patients with the continuous type of OPLL and others. Deterioration of myelopathy could be induced by motion effects even in the connection department of OPLL.

Posterior ligamentous complex injuries are related to fracture severity and neurological damage in patients with acute thoracic and lumbar burst fractures

PURPOSE

The proposed the thoracolumbar injury classification system (TLICS) for thoracolumbar injury cites the integrity of the posterior ligamentous complex (PLC). However, no report has elucidated the severity of damage in thoracic and lumbar injury with classification schemes by presence of the PLC injury. The purpose of this study was to accurately assess the severity of damage in thoracic and lumbar burst fractures with the PLC injuries.

MATERIALS AND METHODS

One hundred consecutive patients treated surgically for thoracic and lumbar burst fractures were enrolled in this study. There were 71 men and 29 women whose mean age was 36 years. Clinical and radiologic data were investigated, and the thoracolumbar injury classification schemes were also evaluated. All patients were divided into two groups (the P group with PLC injuries and the C group without PLC injuries) for comparative examination.

RESULTS

Fourth-one of 100 cases showed PLC injuries in MRI study. The load sharing classification score was significantly higher in the P group [7.8±0.2 points for the P group and 6.9±1.1 points for the C group (p<0.001)]. The TLICS (excluded PLC score) score was also significantly higher in the P group [6.2±1.1 points for the P group and 4.0±1.4 points for the C group (p<0.001)].

CONCLUSION

The presence of PLC injury significantly influenced the severity of damage. In management of thoracic lumbar burst fractures, evaluation of PLC injury is important to accurately assess the severity of damage.

Quantifiable tests for cervical myelopathy; 10-s grip and release test and 10-s step test: standard values and aging variation from 1230 healthy volunteers

PURPOSE

The 10-s grip and release (G&R) test and 10-s step test were reported to be useful tools to evaluate the severity of cervical myelopathy quantitatively. The purpose of this study is to establish the standard values of the 10-s G&R test and 10-s step test as quantitative tests for cervical myelopathy and to elucidate the aging variation and gender difference of those values in a large cohort of normal subjects.

METHODS

A total of 1230 healthy volunteers were enrolled. They included at least 100 men and 100 women in each decade from the 20s to 70s. Three tests were performed: the number of finger grips and releases in 10 s, number of steps in 10 s, and gripping power.

RESULTS

The average number of G&Rs on the weaker side was 21.5 ± 5.5, whereas the average number of steps was 19.7 ± 3.4. The average gripping power on the weaker side was 29.5 ± 9.6 kg. The number of G&Rs and steps in 10 s decreased significantly with age (r = -0.58, -0.43, respectively). The average number of G&Rs on the weaker side was <20 in the 60s and 70s. The number of G&Rs was significantly correlated with the number of steps and gripping power. A significant difference was seen between the genders in all three tests.

CONCLUSION

The standard values of the 10-s G&R test, 10-s step test, and gripping power were established in this study. When these quantifiable tests are used as screening tests of cervical myelopathy, aging variation and gender difference should be considered.

Characterizing the need for tracheostomy placement and decannulation after cervical spinal cord injury

PURPOSE

There have been few reports on the risk factors for tracheostomy and the possibility of patients for decannulation. The purpose of this study was to identify factors necessitating tracheostomy after cervical spinal cord injury (SCI) and detect features predictive of successful decannulation in tracheostomy patients.

METHODS

One hundred and sixty four patients with cervical fracture/dislocation were retrospectively reviewed. The patients comprised 142 men and 22 women with a mean age of 44.9 years. The clinical records were reviewed for patients' demographic data, smoking history, level of cervical spine injury, injury patterns, neurological status, evidence of direct thoracic trauma and head injury, tracheostomy placement, and decannulation. Risk factors necessitating tracheostomy and factors predicting decannulation were statistically analysed.

RESULTS

Twenty-five patients (15.2%) required tracheostomy. Twenty-one patients were successfully decannulated. Smoking history (relative risk [RR], 3.05; p = 0.03) and complete SCI irrespective of injury level (C1-4 complete SCI: RR, 67.55; p < 0.001, C5-7 complete SCI: RR, 57.88; p < 0.001) were significant risk factors necessitating tracheostomy. C1-4 complete SCI was more frequent among those who could not be decannulated. However, even in patients with high cervical complete SCI at the time of injury, patients regaining sufficient movement to shrug their shoulders within 3 weeks after injury could later be decannulated.

CONCLUSIONS

The risk factors for tracheostomy after complete SCI were a history of smoking and complete paralysis irrespective of the level of injury. High cervical level complete SCI was found to be a risk factor for the failure of decannulation in patients without shoulder shrug within 3 weeks after injury.

Observation of the (Λ)(7)He hypernucleus by the (e, e'K+) reaction

An experiment with a newly developed high-resolution kaon spectrometer and a scattered electron spectrometer with a novel configuration was performed in Hall C at Jefferson Lab. The ground state of a neutron-rich hypernucleus, (Λ)(7)He, was observed for the first time with the (e, e'K+) reaction with an energy resolution of ~0.6 MeV. This resolution is the best reported to date for hypernuclear reaction spectroscopy. The (Λ)(7)He binding energy supplies the last missing information of the A = 7, T = 1 hypernuclear isotriplet, providing a new input for the charge symmetry breaking effect of the ΛN potential.

The complement of the load-sharing classification for the thoracolumbar injury classification system in managing thoracolumbar burst fractures

BACKGROUND

The classification and therapeutic strategy for thoracolumbar burst fractures are controversial. The load-sharing classification (LSC) and thoracolumbar injury classification system (TLICS) are both quantitative evaluation systems for thoracolumbar burst fractures. We hypothesized that their combination would be helpful not only for surgical indications but also for deciding on the surgical approach. However, no reports have evaluated the relationship between them. The purpose of this study was to clarify the relationship between the LSC and TLICS and investigate the clinical usefulness of their combination.

METHODS

This study included 100 consecutive patients surgically treated for thoracolumbar burst fractures (71 men and 29 women; mean age 36 years). Clinical and radiographical data as well as thoracolumbar injury classification systems were evaluated.

RESULTS

LSC and TLICS scores were found to be statistically correlated. The mean LSC score with a TLICS score of 5 or more (surgical treatment recommended) was 7.3 ± 1.2 points, and the mean LSC score with a TLICS score of 3 or less (conservative treatment recommended) was 6.1 ± 1.3 points. The mean TLICS score with an LSC score of 7 or more (additional anterior reconstruction recommended) was 6.6 ± 2.7 points, and the mean TLICS score with an LSC score of 6 or less (expectation of good clinical results with posterior short fusion) was 5.0 ± 2.5 points. The TLICS score was 3 or less, and the LSC score was 7 or more in 13 patients (13 %).

CONCLUSION

Although the TLICS scores correlated with the LSC scores, a single application of TLICS might not be sufficient to identify those patients who have a TLICS score of 3 or less and an LSC score of 7 or more as surgically indicated. However, an additional LSC evaluation avoided deviations as the two classifications complemented each other, and it was useful in determining the best treatment options for thoracolumbar burst fractures.

Cervical degenerative intraspinal cyst: a case report and literature review involving 132 cases

Intraspinal and extradural cysts in the cervical spine are rare disorders that may cause myelopathy or radiculopathy. A synovial cyst or ganglion derived from the facet joint and that from a ligamentum flavum have been reported. We report a surgical case of degenerative intraspinal cyst, causing cervical myelopathy. MRI of a case revealed cystic lesion at C4-5. Spinal cord was compressed by cyst and symptoms of myelopathy were also observed. The patient with cervical spinal canal stenosis underwent laminoplasty and excision of the cyst. The patient recovered well immediately after the surgery. Literature review showed that 133 patients have been reported, including the present case. Previous reports indicated that most cysts occurred in old patients and at the atlanto-axial or C7-T1 junction, and laminectomy or laminoplasty with excision of the cyst gave good results in most cases.

Cervical pedicle screw fixation in traumatic cervical subluxation after laminectomy using the pedicle axis view technique under fluoroscopy

Cervical pedicle screw (CPS) fixation has recently been performed in patients in need of cervical reconstruction. We report the case of a 50-year-old man who was operated for traumatic cervical vertebra subluxation using CPS fixation, in whom laminectomy had been performed in the past. We performed CPS fixation using the pedicle axis view technique under fluoroscopy. The four pedicle screws were accurately inserted within the pedicles without perforating the bone cortex of the pedicles. A navigation system is useful for cervical spine surgery because it enables a surgeon to perform relatively safe and accurate surgery during transpedicular screw fixation. However, attachment of the stereotactic reference arc to the spinous process is impossible, and the application of a navigation system is limited in cases in which laminectomy has been performed in the past. We have been using the pedicle axis view technique under fluoroscopy and have found that if we take care of the entry point accurately, we can safely insert the pedicle screw in cases with fewer landmarks.

Spontaneous hemorrhage in an upper lumbar synovial cyst causing subacute cauda equina syndrome

Lumbar spine synovial cysts are becoming more frequent, and they are generally associated with degenerative lumbar spinal disease. They are common in lower lumbar lesions but rare in upper lumbar lesions. Several cases of hemorrhage into lower lumbar juxtafacet cysts after trauma or anticoagulation therapy have been reported in the literature. This article describes a case of subacute cauda equina syndrome resulting from spontaneous hemorrhage into an upper lumbar synovial cyst. A 65-year-old man presented with a 3-month history of intermittent bilateral lumbar pain. One week before, he experienced a sudden exacerbation of lumbar pain and began falling frequently; he also reported weakness and tingling in his lower limbs. A hematic collection associated with a large juxtafacet cyst at L2-L3 was suspected on magnetic resonance imaging. He underwent surgical decompression, and the cyst was resected. Microscopic examination was consistent with the diagnosis of a synovial cyst. Two days postoperatively, he was walking independently. Although several descriptions exist of hemorrhagic lumbar juxtafacet cysts after trauma or anticoagulant therapy, to the authors' knowledge, this is the first documented case of hemorrhage in an upper lumbar synovial cyst with no previous traumatic event or medication use. Magnetic resonance imaging was essential in making the preoperative diagnosis. Surgical removal of the cyst was an effective treatment.

Multivariate analysis of C-5 palsy incidence after cervical posterior fusion with instrumentation

Object

Postoperative C-5 palsy is a significant complication resulting from cervical decompression procedures. Moreover, when cervical degenerative diseases are treated with a combination of decompression and posterior instrumented fusion, patients are at increased risk for C-5 palsy. However, the clinical and radiological features of this condition remain unclear. Therefore, the purpose of this study was to clarify the risk factors for developing postoperative C-5 palsy.

Methods

Eighty-four patients (mean age 60.1 years) who had undergone posterior instrumented fusion using cervical pedicle screws to treat nontraumatic lesions were independently reviewed. The authors analyzed the medical records of some of these patients who developed postoperative C-5 palsy, paying particular attention to their plain radiographs, MRI studies, and CT scans. Risk factors for postoperative C-5 palsy were assessed using multivariate logistic regression analysis. The cutoff values for the pre- and postoperative width of the intervertebral foramen (C4–5) were determined by receiver operating characteristic curve analysis.

Results

Ten (11.9%) of 84 patients developed postoperative C-5 palsy. Seven patients recovered fully from the neurological complications. The pre- and postoperative C4–5 angles showed significant kyphosis in the C-5 palsy group. The pre- and postoperative diameters of the C4–5 foramen on the palsy side were significantly smaller than those on the opposite side in the C-5 palsy group and those bilaterally in the non–C5 palsy group. Risk factors identified by multivariate logistic regression analysis were as follows: 1) ossification of the posterior longitudinal ligament (relative risk [RR] 7.22 [95% CI 1.03–50.55]); 2) posterior shift of the spinal cord (C4–5) (RR 1.73 [95% CI 1.00–2.98]); and 3) postoperative width of the C-5 intervertebral foramen (RR 0.33 [95% CI 0.14–0.79]). The cutoff values of the pre- and postoperative widths of the C-5 intervertebral foramen for C-5 palsy were 2.2 and 2.3 mm, respectively.

Conclusions

Patients with preoperative foraminal stenosis, posterior shift of the spinal cord, and additional iatrogenic foraminal stenosis due to cervical alignment correction were more likely to develop postoperative C-5 palsy after posterior instrumentation with fusion. Prophylactic foraminotomy at C4–5 might be useful when preoperative foraminal stenosis is present on CT. Furthermore, it might be useful for treating postoperative C-5 palsy. To prevent excessive posterior shift of the spinal cord, the authors recommend that appropriate kyphosis reduction should be considered carefully.

Prediction of lower limb functional recovery after laminoplasty for cervical myelopathy: focusing on the 10-s step test

OBJECTIVE

Operative decompression is indicated for progressive neurological deterioration in patients with cervical compressive myelopathy (CCM). However, the best timing to ensure clinical recovery has not been determined because of the lack of a suitable method. 10 s step ("step") test is an easily performed physical test to assess the severity of CCM, particularly for the severity of lower limb dysfunction. The purpose of this study was to analyze the predictive value of preoperative step test results in relation to the results of expansive laminoplasty in patients with CCM.

MATERIALS AND METHODS

Clinical and imaging data were prospectively collected from 101 patients who underwent cervical expansive laminoplasty for CCM. The Japanese Orthopedic Association (JOA) score and the lower limb function section of the Japanese Orthopedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ-L) were used to evaluate surgical outcomes. Cutoff value was determined by receiver operating characteristic curve analysis to predict clinical recovery after surgery. JOA recovery rate exceeding 50% was defined as an effective clinical result. The treatment was judged to be effective in 30 patients based on the JOACMEQ-L. The cutoff value of the step test was 14.5 in cases of an effective judgment with JOA and JOACMEQ-L. Multivariate analysis showed that preoperative patient age and duration of symptoms were predictive parameters for effectively judging JOA scores. A preoperative step test result of greater than or equal to 14.5 and male gender were significant predictive parameters for an effective judgment with JOACMEQ-L.

CONCLUSIONS

Preoperative step test results significantly reflected the effective results of JOACMEQ-L and were predictive of improved lower limb function after laminoplasty in patients with CCM. Patients with a score of greater than or equal to 14.5 can experience effective lower limb functional recovery.

Age-related changes in osseous anatomy, alignment, and range of motion of the cervical spine. Part I: Radiographic data from over 1,200 asymptomatic subjects

PURPOSE

This study aimed to establish radiographic standard values for cervical spine morphometry, alignment, and range of motion (ROM) in both male and female in each decade of life between the 3rd and 8th and to elucidate these age-related changes.

METHODS

A total of 1,230 asymptomatic volunteers underwent anteroposterior (AP), lateral, flexion, and extension radiography of the cervical spine. There were at least 100 men and 100 women in each decade of life between the 3rd and 8th. AP diameter of the spinal canal, vertebral body, and disc were measured at each level from the 2nd to 7th cervical vertebra (C2-C7). C2-C7 sagittal alignment and ROM during flexion and extension were calculated using a computer digitizer.

RESULTS

The AP diameter of the spinal canal was 15.8 ± 1.5 [mean ± standard deviation (SD)] mm at the mid-C5 level, and 15.5 ± 2.0 mm at the C5/6 disc level. The disc height was 5.8 ± 1.3 mm at the C5/6 level, which was the minimum height, and the maximum height was at the C6/7 level. Both the AP diameter of the spinal canal and disc height decreased gradually with increasing age. The C2-C7 sagittal alignment and total ROM were 13.9 ± 12.3° in lordosis and 55.3 ± 16.0°, respectively. The C2-C7 lordotic angle was 8.0 ± 11.8° in the 3rd decade and increased to 19.7 ± 11.3 in the 8th decade, whereas the C2-C7 ROM was 67.7 ± 17.0° in the 3rd decade and decreased to 45.0 ± 12.5 in the 8th decade. The extension ROM decreased more than the flexion ROM, and lordotic alignment progressed with increasing age. There was a significant difference in C2-C7 alignment and ROM between men and women.

CONCLUSIONS

The standard values and age-related changes in cervical anatomy, alignment, and ROM for males and females in each decade between the 3rd and 8th were established. Cervical lordosis in the neutral position develops with aging, while extension ROM decreases gradually. These data will be useful as normal values for the sake of comparison in clinical practice.

Examination of the influence of ossification of the anterior longitudinal ligament on symptom progression and surgical outcome of ossification of the thoracic ligamentum flavum: a multicenter study

Object

The purpose of this study was to provide the first evidence for the influence of an ossified anterior longitudinal ligament (OALL) on the clinical features and surgical outcomes in an ossified ligamentum flavum (OLF) in the thoracic region.

Methods

Sixty-three patients who underwent surgery for a 1-level thoracic OLF were identified, and preoperative symptoms, severity of symptoms and myelopathy, disease duration, MR imaging and CT findings, surgical procedure, intraoperative findings, complications, and postoperative recovery were investigated in these patients. Entities of OALLs were found on sagittal CT images to be adjacent to or at the same vertebral level as the OLF were classified into 4 types: no discernible type (Type N), one-sided (Type O), discontinuous (Type D), and continuous (Type C).

Results

The duration of symptoms was especially long for Types D and C OALLs. Patients with Type D OALLs had a significantly worse percentage of recovery, as well as worse preoperative JOA scores.

Conclusions

The authors' results showed that a Type D OALL had strong associations with preoperative severity of symptoms and surgical outcomes. These findings may allow surgeons to determine the severity of preoperative symptoms and the probable surgical outcomes from the OALL classifications. Moreover, surgery with instrumentation for Type D OALLs may produce better surgical outcomes.

Complications of cervical pedicle screw fixation for nontraumatic lesions: a multicenter study of 84 patients

OBJECT

The cervical pedicle screw (PS) provides strong stabilization but poses a potential risk to the neurovascular system, which may be catastrophic. In particular, vertebrae with degenerative changes complicate the process of screw insertion, and PS misplacement and subsequent complications are more frequent. The purpose of this study was to evaluate the peri- and postoperative complications of PS fixation for nontraumatic lesions and to determine the risk factors of each complication.

METHODS

Eighty-four patients who underwent cervical PS fixation for nontraumatic lesions were independently reviewed to identify associated complications. The mean age of the patients was 60.1 years, and the mean follow-up period was 4.1 years (range 6-168 months). Pedicle screw malpositioning was classified on postoperative CT scans as Grade I (< 50% of the screw outside the pedicle) or Grade II (≥ 50% of the screw outside the pedicle). Risk factors of each complication were evaluated using a multivariate analysis.

RESULTS

Three hundred ninety cervical PSs and 24 lateral mass screws were inserted. The incidence of PS misplacement was 19.5% (76 screws); in terms of malpositioning, 60 screws (15.4%) were classified as Grade I and 16 (4.1%) as Grade II. In total, 33 complications were observed. These included postoperative neurological complications in 11 patients in whom there was no evidence of screw misplacement (C-5 palsy in 10 and C-7 palsy in 1), implant failure in 11 patients (screw loosening in 5, broken screws in 4, and loss of reduction in 2), complications directly attributable to screw insertion in 5 patients (nerve root injury by PS in 3 and vertebral artery injury in 2), and other complications in 6 patients (pseudarthrosis in 2, infection in 1, transient dyspnea in 1, transient dysphagia in 1, and adjacent-segment degeneration in 1). The multivariate analysis showed that a primary diagnosis of cerebral palsy was a risk factor for postoperative implant failure (HR 10.91, p = 0.03) and that the presence of preoperative cervical spinal instability was a risk factor for both Grade I and Grade II screw misplacement (RR 2.12, p = 0.03), while there were no statistically significant risk factors for postoperative neurological complications in the absence of evidence of screw misplacement or complications directly attributable to screw insertion.

CONCLUSIONS

In the present study, misplacement of cervical PSs and associated complications occurred more often than in previous studies. The rates of screw-related neurovascular complications and neurological deterioration unrelated to PSs were high. Insertion of a PS for nontraumatic lesions is surgically more challenging than that for trauma; consequently, experienced surgeons should use PS fixation for nontraumatic cervical lesions only after thorough preoperative evaluation of each patient's cervical anatomy and after considering the risk factors specified in the present study.

Pyogenic cervical spondylitis caused by Pasteurella haemolytica attributed to excessive contact with dogs

The bacterium Pasteurella haemolytica is resident in the oral cavities of dogs and cats and is often a cause of zoonotic infection. However, it is rare for it to be the pathogenic bacteria behind pyogenic spondylitis, and few studies have been conducted on it. This article reports a case of pyogenic cervical spondylitis thought to be caused by excessive contact with pet dogs.A 52-year-old man reported neck pain and pain in the right upper limb. He was admitted after plain radiographs and magnetic resonance imaging suggested pyogenic spondylitis. Pasteurella haemolytica was detected by needle aspiration biopsy of the intervertebral disk. Because the patient owned 2 dogs and frequently kissed them on the mouth, the cause of infection was thought to be excessive contact with pet dogs. Symptoms were alleviated with bed rest and administration of antibiotics with a higher sensitivity to this bacterium.

Differentiation of localization of spinal hemangioblastomas based on imaging and pathological findings

Intramedullary + extramedullary hemangioblastomas with largely extramedullary growth are rare and often incorrectly assigned as intradural-extramedullary tumors preoperatively. Preoperative evaluation of the precise tumor location is important for total resection of tumor and improving the surgical outcome. The aim of this study was to provide the first identification of the key differences among of preoperative MR images of hemangioblastomas in different locations and to correlate these with pathological findings. The subjects were 26 patients with surgery for spinal hemangioblastoma in our department, including 6 with an intramedullary tumor who were complicated with von Hippel Lindau disease. Intramedullary, intramedullary + extramedullary, and intradural-extramedullary tumors were present in 22, 3 and 1 cases, respectively. Sagittal MR images showed that intramedullary and intramedullary + extramedullary tumors gave intramedullary T2 high intensity areas (HIAs) spreading toward the craniocaudal sides of the tumor, whereas such findings were absent for the intradural-extramedullary tumor. All the tumors showed strong contrast on axial images, with focal enhancement of hemangioblastomas limited to the intramedullary region (focal type); smooth boundary lines between the spinal cord and the extramedullary tumor (smooth type); and a snowman sign for intramedullary + extramedullary tumors, which provided a key characteristic for differentiating intramedullary + extramedullary tumors from those limited to the extramedullary region. In pathological findings, the Ki67 activity was less than 1% for intramedullary and intradural-extramedullary tumors, but 18-25% in all cases with an intramedullary + extramedullary tumor. In conclusion, on preoperative MRI, a change in the intramedullary HIAs spreading the craniocaudal sides of the tumor on sagittal T2 weighted image (T2WI) and a snowman sign on contrast axial T1WI may be important for differentiation among spinal hemangioblastomas in different locations. Pathologically, we found that intramedullary + extramedullary hemangioblastoma has high cell proliferative activity, which may suggest that enlargement of this tumor occurs faster than that of intramedullary hemangioblastoma.

Extension CT scan: its suitability for assessing fusion after posterior lumbar interbody fusion

Posterior lumbar interbody fusion (PLIF) is a popular procedure for treating lumbar canal stenosis with spinal instability, and several reports concerning fusion assessment methods exist. However, there are currently no definitive criteria for diagnosing a successful interbody fusion in the lumbar spine. We suggested evaluating fusion status using computed tomography (CT) in extension position to detect pseudoarthrosis more precisely. The purpose of this study was to evaluate its usefulness for determining bone union quality after PLIF. Eighty-one patients who underwent PLIF at 97 levels were retrospectively enrolled. The study population included 48 men and 33 women (mean age 58.9 years, range 21-85 years). Patients were followed up for more than 12 months after surgery. The mean follow-up period was 27.6 months (range 14-49 months). Fusion status was evaluated using three ways: flexion-extension radiographs, CT images in flexion and extension position. In the flexion-extension radiographs, mobility of more than 3°, a remaining clear zone, or an uncertain bone connection constituted an incomplete union. For CT images, a remaining clear zone, a gas pattern, or an uncertain bone connection constituted an incomplete union. Flexion-extension radiographs demonstrated a solid fusion in 90.7% of the 97 levels at 10.7 months postoperatively. When fusion was demonstrated on flexion-extension radiographs, the rate of fusion affirmed by flexion CT and extension CT was 87.6 and 69.1% of the levels assessed, respectively. The rate of pseudoarthrosis detected on extension CT images was significantly higher than that on flexion-extension radiographs (P < 0.001) and flexion CT (P < 0.01). The rate of fusion achieved on extension CT was 85.6% at 15.1 months postoperatively. Extension CT could detect pseudoarthrosis more clearly than flexion-extension radiography and flexion CT. The CT images are influenced by body position and dilating anterior disc space in extension CT contributes to detect pseudoarthrodesis. Thus, extension CT was a useful method for assessing fusion status after PLIF.

Posterior approach for cervical fracture-dislocations with traumatic disc herniation

In the treatment algorithm for cervical spine fracture-dislocations, the recommended approach for treatment if there is a disc fragment in the canal is the anterior approach. The posterior approach is not common because of the disadvantage of potential neurological deterioration during reduction in traumatic cervical herniation patients. However, reports about the frequency of this deterioration and the behavior of disc fragments after reduction are scarce. Forty patients with traumatic disc herniation were observed. They represented 29.2% of 137 consecutive patients with subaxial cervical spine fracture-dislocations. Surgical planning was performed according to our two-stage algorithm. In the first stage, they were treated with posterior open reduction and posterior spine arthrodesis. In the second stage, anterior surgery was added for cases where neurological deterioration attributed to non-reduced disc fragments on postoperative magnetic resonance imaging (MRI). Neurological deterioration after posterior open reduction was not observed. Furthermore, 25% of total cases and 75% of incomplete paralysis cases improved postoperatively by ≥ 1 grade in the American Spinal Injury Association impairment scale. Reduction or reversal of disc herniation was observed in all cases undergoing postoperative MRI. For local sagittal alignment, preoperative 9.4° kyphosis was corrected to 6.9° lordosis postoperatively. The disc height ratio was 72.4% preoperatively and 106.3% postoperatively. The second stage of our plan was not required after the posterior approach in this series. The incidence of neurological deterioration after posterior open reduction was zero, even in cases with traumatic cervical disc herniation. Favorable clinical and radiological outcomes could be obtained by the first stage alone. Although preparations for prompt anterior surgery should always be made to cover any contingency, the need for them is minimal.

Clonal distribution of enterotoxigenic Staphylococcus aureus on handles of handheld shopping baskets in supermarkets

AIMS

Shopping carts and handheld shopping baskets in supermarkets are subject to accidental bacterial contamination through contacts with a variety of food. We investigated the prevalence of Staphylococcus aureus on the handles of handheld shopping baskets in four supermarkets distantly located in Osaka district, Japan.

METHODS AND RESULTS

Fifty two strains of Staph. aureus were isolated from 760 basket handles. Among these, six strains were positive for staphylococcal enterotoxin B (SEB) production, representing 12% of total. This SEB producer ratio is considerably higher than among Staph. aureus isolated from nasal swabs of the supermarket workers (2%) and from independently collected clinical specimens (4%). These SEB-producing Staph. aureus strains from the basket handles are clonal and belong to ST12. Coagulase typing showed that they are in group VII, which is the most common cause of food poisoning in Japan. Biofilm assays indicated that SEB gene (seb)-positive strains including this clone produced a significantly higher amount of biofilm than seb-negative strains.

CONCLUSIONS

The frequent isolation of seb-positive Staph. aureus on shopping basket handles raises the possibility that they could be a hidden reservoir for Staph. aureus with a potential to cause food poisoning and draws attention to the importance of shopping basket sanitation.