Discovery of moganite in a lunar meteorite as a trace of H2O ice in the Moon's regolith.

Moganite, a monoclinic SiO2 phase, has been discovered in a lunar meteorite. Silica micrograins occur as nanocrystalline aggregates of mostly moganite and occasionally coesite and stishovite in the KREEP (high potassium, rare-earth element, and phosphorus)-like gabbroic-basaltic breccia NWA 2727, although these grains are seemingly absent in other lunar meteorites. We interpret the origin of these grains as follows: alkaline water delivery to the Moon via carbonaceous chondrite collisions, fluid capture during impact-induced brecciation, moganite precipitation from the captured H2O at pH 9.5 to 10.5 and 363 to 399 K on the sunlit surface, and meteorite launch from the Moon caused by an impact at 8 to 22 GPa and >673 K. On the subsurface, this captured H2O may still remain as ice at estimated bulk content of >0.6 weight %. This indicates the possibility of the presence of abundant available water resources underneath local sites of the host bodies within the Procellarum KREEP and South Pole Aitken terranes.

Escherichia coli Vertebral Osteomyelitis Diagnosed According to Broad-range 16S rRNA Gene Polymerase Chain Reaction (PCR).

Identifying the causative agent of pyogenic osteomyelitis is often challenging, especially when antibiotics are administered before a biopsy. We herein present a case of osteomyelitis in the cervical vertebrae presenting with progressive paralytic symptoms, in which we successfully identified Escherichia coli from a biopsy specimen using broad-range 16S rRNA gene polymerase chain reaction (PCR) even though sensitive antibiotics had been used for more than 50 days before the biopsy. Broad-range 16S rRNA gene PCR is a useful diagnostic method, especially when prebiopsy antibiotics are unavoidably used for a clinically unstable state.

Parvimonas micra as a causative organism of spondylodiscitis: a report of two cases and a literature review.

Spondylodiscitis caused by Parvimonas micra, a rarely reported infection, might be under-detected using conventional methods. This report of the detection and treatment of two cases of spondylodiscitis due to P. micra and review of the literature indicates that the use of gene sequencing methods might improve the accuracy of diagnosing this infection.

Morphological characteristics of cervical spine in patients with athetoid cerebral palsy and the accuracy of pedicle screw placement.

STUDY DESIGN: A retrospective study. OBJECTIVE: To investigate the morphology of the cervical spine in patients with athetoid cerebral palsy (CP), and to evaluate its relationship with the breach of cervical pedicle screws. SUMMARY OF BACKGROUND DATA: Cervical pedicle screws have been increasingly used in surgery for patients with CP, but screw misplacement is not uncommon. Although the altered morphology of the cervical spine in patients with CP may result in this high breach rate, few studies have examined the cervical pedicle profile. METHODS: We retrospectively analyzed 31 patients with cervical myelopathy with CP, as well as 30 patients with cervical spondylotic myelopathy (CSM), who underwent posterior decompression surgery. The pedicle outer diameter, inner diameter, transverse angle and lateral mass deformity were investigated by obtaining preoperative computed tomographic scans. The accuracy of the placement of 56 pedicle screws used in fusion surgery for 12 patients with CP was also analyzed using postoperative computed tomographic scans. RESULTS: The outer diameter of the pedicle in CP was in the range from 3.3 to 9.6 mm, and was larger than that in CSM at all cervical levels except for C7. Pedicle sclerosis was more frequently observed in CP than in CSM (23% vs. 7.3%, P < 0.001). The transverse angle at C3 and C4 was larger, and lateral mass deformity was more frequently observed in CP than in CSM. The critical breach of pedicle screws in CP was found in 29%. A multivariate analysis revealed that pedicle sclerosis was associated with an increased risk of breach (odds ratio: 6.3; 95% confidence interval: 1.03-39.0; P = 0.047). CONCLUSION: The pedicle diameter in patients with CP was relatively large, but pedicle sclerosis, a wide transverse angle and lateral mass deformity were frequently observed. Sclerotic pedicles were associated with a higher risk of critical breach. LEVEL OF EVIDENCE: N/A.

Comparison of spinal deformity surgery in patients with non-insulin-dependent diabetes mellitus (NIDDM) versus controls.

STUDY DESIGN: A retrospective review. OBJECTIVE: To quantify the exact impact of non-insulin-dependent diabetes mellitus (NIDDM) on operative complications and additional surgeries associated with spinal deformity surgery. SUMMARY OF BACKGROUND DATA: There are many references supporting diabetes mellitus (DM) as one of the major risk factors for perioperative complications in spinal surgery. However, the results vary depending on the type of DM, suggesting that insulin-dependent DM causes more complications than NIDDM, which is far more prevalent in the adult population with spinal deformity. METHODS: Among 5119 adult patients (older than 40 yr) with deformities, 23 patients with NIDDM and 23 control (group C) patients with a minimum 2-year follow-up were selected. Both groups were matched for age at surgery, sex, body mass index, number of comorbidities, smoking history, current and prior fusion levels, estimated blood loss, and the amount of transfusion. Pre- and final Scoliosis Research Society (SRS) scores and Oswestry Disability Index (ODI), number of perioperative complications, and additional surgeries were compared. Within the group with NIDDM, patients with (+) or without (-) complications were compared in terms of postoperative glucose control. RESULTS: There were no significant differences in the number of major or minor complications or additional surgeries between the 2 groups. There was no significant difference in postoperative glucose control with the NIDDM group (+) and (-). Group C reported significantly improved scores at final follow-up in all SRS domains and ODI. The group with NIDDM reported improvement in all domains except for the mental health and pain domains. However, there were no significant differences between the group with NIDDM and group C in terms of SRS and ODI scores preoperatively and postoperatively. CONCLUSION: Contrary to traditional thinking, properly selected NIDDM was not a significant risk factor for perioperative complications or additional surgeries in adult patients with spinal deformities.

Aorta movement in patients with scoliosis after posterior surgery.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To evaluate movement of the aorta in patients with scoliosis who have undergone the posterior correction and fusion. SUMMARY OF BACKGROUND DATA: Surgeons check preoperative imaging for pedicle screw placement, but past analyses indicated that the aorta shifts after scoliosis surgery. Few studies, however, evaluated the aorta movement in detail. METHODS: A total of 22 patients with a right thoracic curve underwent posterior instrumentation and fusion. The average age at surgery was 17.2 years. The average of the preoperative Cobb angle was 65.2° which decreased to 20.0°.Computed-tomographic data were analyzed by multiplanar reconstruction. In our coordinate system, the middle of the base of the left superior facet was set as the origin and a line connecting the middle points of both bases of the superior facets was defined as the X-axis. We defined the angle and the distance to describe the aorta position and analyzed the movement of the aorta relative to the spine. Deformity parameters were examined to determine their correlation with the aorta parameters.We simulated variable pedicle screw placement and defined a warning pedicle when the aorta enters the expected area of the screw and examined them in 24 scenarios. RESULTS: The aorta moved 4.7 ± 3.0 mm on an average. The aorta had a tendency to migrate in the anteromedial direction and this movement correlated with preoperative apical vertebral translation, preoperative sagittal alignment, and change of sagittal alignment. The ratio of warning pedicles at the middle thoracic level (T7-T9) increased after deformity correction. CONCLUSION: The aorta moved anteromedially relative to the spine after the posterior correction and the risk of the aorta by a pedicle screw increased by correction of the deformity at the middle thoracic spine. Surgeons are recommended to anticipate the aorta movement in the surgical planning.

Correlation between pyramidal signs and the severity of cervical myelopathy.

A retrospective study was performed to determine the sensitivities of the pyramidal signs in patients with cervical myelopathy, focusing on those with increased signal intensity (ISI) in T2-weighted magnetic resonance imaging (MRI). The relationship between prevalence of the pyramidal signs and the severity of myelopathy was investigated. We reviewed the records of 275 patients with cervical myelopathy who underwent surgery. Of these, 143 patients were excluded from this study due to comorbidities that might complicate neurological findings. The MR images of the remaining 132 patients were evaluated in a blinded fashion. The neurological findings of 120 patients with ISI (90 men and 30 women; mean age 61 years) were reviewed for hyperreflexia (patellar tendon reflex), ankle clonus, Hoffmann reflex, and Babinski sign. To assess the severity of myelopathy, the motor function scores of the upper and lower extremities for cervical myelopathy set by the Japanese Orthopaedic Association (m-JOA score) were used. The most prevalent signs were hyperreflexia (94%), Hoffmann reflex (81%), Babinski sign (53%), and ankle clonus (35%). Babinski sign (P < 0.001), ankle clonus, and Hoffmann reflex showed significant association with the lower m-JOA score. Conversely, no association was found with the upper m-JOA score. In patients with cervical myelopathy, hyperreflexia showed the highest sensitivity followed by Hoffmann reflex, Babinski sign, and ankle clonus. The prevalence of the pyramidal signs correlated with increasing severity of myelopathy. Considering their low sensitivity in patients with mild disability, the pyramidal signs may have limited utility in early diagnosis of cervical myelopathy.

New parameters to represent the position of the aorta relative to the spine for pedicle screw placement.

Parameters of the position of the aorta in previous reports were determined for anterior surgery. This study evaluated the relative position of the aorta to the spine by new parameters, which could enhance the safety of pedicle screw placement. Three parameters were defined in a new Cartesian coordinate system. We selected an entry point of a left pedicle screw as the origin. The transverse plane was determined to include both the bases of the superior facet and to be parallel to the upper endplate of the vertebral body. A line connecting the entry points of both sides was defined as the X-axis. The angle formed by the Y-axis and a line connecting the origin and the center of the aorta was defined as the left pedicle-aorta angle. The length of a line connecting the origin and the aorta edge was defined as the left pedicle-aorta distance. Distance from the edge of the aorta to the X-axis was defined as the pedicular line-aorta distance. These parameters were measured preoperatively in 293 vertebral bodies of 24 patients with a right thoracic curve. We simulated the placement of the pedicle screw with variable length and with some direction error. We defined a warning pedicle as that when the aorta enters the expected area of the screw. Sensitivity analysis was performed to find the warning pedicle ratio in 12 scenarios. The left pedicle-aorta angle averaged 29.7 degrees at the thoracic spine and -16.3 degrees at the lumbar spine; the left pedicle-aorta distance averaged 23.7 and 55.2 mm; the pedicular line-aorta distance averaged 18.3 and 51.0 mm, respectively. The ratio of warning pedicles was consistently high at T4-5 and T10-12. When a left pedicle screw perforates an anterior/lateral wall of the vertebral body, the aorta may be at risk. These new parameters enable surgeons to intuitively understand the position of the aorta in surgical planning or in placement of a pedicle screw.

Diameter, length, and direction of pedicle screws for scoliotic spine: analysis by multiplanar reconstruction of computed tomography.

STUDY DESIGN: A morphometric study of thoracic and lumbar spine in scoliosis. OBJECTIVE: The purpose of the present study was to evaluate the appropriate values of diameter, length, and direction of pedicle screws with a straightforward trajectory in scoliosis. SUMMARY OF BACKGROUND DATA: Several authors have analyzed the pedicle shape and evaluated the feasibility of pedicle screws in the scoliotic spine. To date, however, none of them have reported analysis by multiplanar reconstruction of computed tomography. METHODS: Computed tomography with a thickness of 1.25 mm was obtained before surgery in 41 Japanese with scoliosis. A total of 1100 pedicles were evaluated by simulating screw placement with the straightforward approach in a multiplanar reconstruction image. We chose the optimal slice where the insertion point and direction were determined to get the largest diameter of a screw in every vertebra. Length from the insertion point to the tip of the simulated screw was measured. RESULTS: Screws of L1 and L2 were significantly smaller than those of T12 and L3 (P < 0.001). On the concave side, 37% of T3-T9 pedicles did not accept a 4-mm diameter screw even with 25% expansion. Length on the convex side was shorter at T5 and T7-T9 than that on the concave side (P < 0.05). On the convex side, 11% at T4-T8 vertebrae did not accept a 25-mm length screw. Average angle of screws of T1, T2, and L5 was greater than 15 degrees and 17% of the screws at T7-T10 were placed in the lateral direction. CONCLUSION: In T3-T9 on the concave side, pedicle screws with a straightforward trajectory are not held within 37% of pedicles even with plastic deformation. We recommend that surgeons consider combined use of various types of anchoring when preoperative evaluation reveals narrow pedicles for screw placement.

Sleep apnea in rheumatoid arthritis patients with occipitocervical lesions: the prevalence and associated radiographic features.

Since sleep apnea is a risk factor for high mortality of rheumatoid arthritis (RA) patients, this study examined the prevalence in RA patients with occipitocervical lesions, and the associated radiographic features. Twenty-nine RA patients requiring surgery for progressive myelopathy due to occipitocervical lesions (3 males, 26 females, average age 65 years) were preoperatively evaluated. Twenty-three (79%) had sleep apnea defined as apnea-hypopnea index >5 events per hour measured by a portable monitoring device, and all of them were classified as the obstructive type. Among gender, age, bone mass index (BMI), and radiographic parameters related to occipitocervical lesions: atlantodental interval (ADI), cervical angles (O/C1, C1/2, and C2/6), and cervical lengths (O-C2 and O-C6), the ADI and cervical lengths were shown to be significantly associated with the presence of sleep apnea by parametric statistical analysis. Since there were positive correlations between the ADI and cervical lengths by Pearson's test, we performed a multivariate logistic regression analysis after adjustment for confounding factors and found that small ADI was the principle parameter associated with sleep apnea. We therefore conclude that the prevalence of sleep apnea is higher than that in a general RA population that was reported previously, and believe that occipitocervical lesions are an independent risk factor for this condition. Small ADI and short neck, secondary to the vertical translocation by RA, may cause obstructive sleep apnea, probably through mechanical or neurological collapse of the upper airway.

Radiographic analysis of the cervical spine in patients with retro-odontoid pseudotumors.

STUDY DESIGN: A retrospective review of 10 consecutive patients with a noninflammatory retro-odontoid pseudotumor. OBJECTIVE: To examine the radiographic characteristics in patients with a retro-odontoid pseudotumor and to evaluate the efficacy of posterior fusion. SUMMARY OF BACKGROUND DATA: A retro-odontoid pseudotumor, a reactive fibrocartilaginous mass, is known to develop after chronic atlantoaxial instability; however, one-third of the reported cases showed no overt atlantoaxial instability. The pathomechanism for such "atypical" cases remains unclear, although altered cervical motion secondary to ossification of the anterior longitudinal ligament (OALL) or severe spondylosis has been implicated. METHODS: We reviewed the charts and radiographs of 10 patients with a retro-odontoid pseudotumor who underwent surgery. Preoperative radiographs were evaluated for atlas-dens interval (ADI), presence of OALL, range of motion, and segmental motion adjacent to the atlantoaxial joint. Computed tomography was evaluated for degenerative changes of zygapophysial joints. RESULTS: There were 6 men and 4 women. Atlantoaxial instability (ADI >4 mm) was observed in 2 patients. ADI was less than 3 mm in 5 patients. Frequent association of OALL (6 patients) and marked decrease in C2 to C7 range of motion (mean, 17.6 degrees ; range, 3 degrees-36 degrees ) were noted. Ankylosis of O-C1 was observed in 4 patients and C2 to C3 in 6. Severe degenerative change of C2 to C3 zygapophysial joint was observed in 4 patients. The patients underwent occipito-cervical fusion (9 patients) or direct removal of the pseudotumor (1 patient). Postoperative magnetic resonance imaging invariably demonstrated the mass regression. CONCLUSION: Retro-odontoid pseudotumors were not always associated with radiographic atlantoaxial instability. Our data indicate that extensive OALL and ankylosis of the adjacent segments are risk factors for the formation of the pseudotumor. Retro-odontoid pseudotumors may develop as an "adjacent segment disease" after altered biomechanics of the cervical spine, especially those in the adjacent segments. Posterior fusion was effective even in cases without radiographic atlantoaxial instability.

Ossification of the posterior atlantoaxial membrane and the transverse atlantal ligament.

STUDY DESIGN: Case report. OBJECTIVE: To report a case of ossification of the posterior atlantoaxial membrane (PAAM) and ossification of the transverse ligament of the atlas (TAL). SUMMARY OF BACKGROUND DATA: Ossification of the PAAM and TAL are both very rare clinical entities. This is the first case involving ossification of both the PAAM and TAL with the development of cervical myelopathy. METHODS: Patient's history, physical examination, radiographic evaluation, surgical treatment, and outcome are examined. Relevant literature is also reviewed. RESULTS: The patient's neurological symptoms significantly improved after posterior decompressive surgery. CONCLUSION: Ossification of various parts of the spinal ligament have been reported previously. Among them, ossification of both the PAAM and TAL has never been reported previously and is thus extremely rare. Surgical intervention improved the neurological impairment.

Measurement of occipitocervical angle.

STUDY DESIGN: This study compared the reliability of 3 techniques used to measure alignment between the occiput and cervical spine. OBJECTIVES: Intraobserver and interobserver intraclass correlation coefficient were computed to determine the most reliable method to measure occipitocervical angle. SUMMARY OF BACKGROUND DATA: No studies have been performed comparing occipitocervical angle measurement techniques. METHODS: The angles between the inferior endplate of second cervical vertebrae and the occiput line using the Chamberlain line, McRae line, and McGregor line were measured from lateral cervical radiographs of 30 healthy volunteers. Five spine surgeons made measurements. RESULTS: Mean intraobserver variances of the angles using Chamberlain line, McRae line, and McGregor line were 2.0 degrees (ranging from 0 degrees-15 degrees), 4.7 degrees (from 0 degrees-28 degrees), and 1.5 degrees (from 0 degrees-9 degrees), respectively; intraobserver intraclass correlation coefficients of the angles were 0.956, 0.835, and 0.975. Mean interobserver variances of the angles using Chamberlain line, McRae line, and McGregor line were 2.3 degrees (from 0.4 degrees-6.4 degrees), 5.0 degrees (from 1.8 degrees-11.9 degrees), and 1.4 degrees (from 0 degrees-4.5 degrees), respectively; interobserver intraclass correlation coefficients were 0.939, 0.802, and 0.972. The highest reliability indexes were obtained for McGregor line. CONCLUSIONS: The McGregor line is the most reproducible and reliable method for measurement of the occipitocervical angle.

Computer-assisted anterior spinal surgery for a case of recurrent giant cell tumor.

A computer-assisted image guidance system has recently been used for posterior spinal surgery. We applied this system to anterior revision surgery of the cervicothoracic junction for a patient with recurrent thoracic spinal giant cell tumor. Anterior computer-assisted spinal surgery was achieved by attaching reference markers to threaded pins inserted into a vertebral body. The locations of anatomic structures in the surgical field of this patient were difficult to identify because of previous surgery. Both accurate resection of the tumor and anterior fusion with iliac bone autograft between C6 and T3 were successfully performed using a computer-assisted image guidance system. This system is useful for anterior spinal surgery because it enables a surgeon to perform safe and accurate surgery.