The Development of a Nationwide, Multicenter Electronic Database for Spinal Instrumentation Surgery in Japan: Japanese Spinal Instrumentation Society Database (JSIS-DB).

(1) Background: Despite the number of complicated and expensive spine surgery procedures maintained by the national health insurance system in Japan, until now there has been no large-scale multicenter clinical database for this field to understand and improve healthcare expenditure and treatment outcomes. The purpose of this report is to announce the establishment and methodology of a nationwide registry system for spinal instrumentation surgeries by the Japanese Spinal Instrumentation Society (JSIS), and to report the progress over the first 1.5 years of this database's operation. (2) Methods: The JSIS recently produced an online database with an electronic server. The collected information included patient background, surgery information, and early complications of primary and revision cases. Analysis included data from February 2018, when registration began, to August 2019. (3) Results: As of August 2019, 73 facilities have completed the required paperwork to start, and 55 facilities have registered cases. Of the total 5456 registered cases, 4852 were valid and 2511 were completed. (4) Conclusions: JSIS-DB, the nationwide web-based registry system for spinal instrumentation surgery in Japan, was launched for the purpose of research, healthcare policy regulation, and improved patient care, and its methodology and progress in the first 1.5 years are reported in this study.

A Japanese nationwide multicenter survey on perioperative complications of corrective fusion for elderly patients with adult spinal deformity.

BACKGROUND: Recently, corrective fusion surgery for patients with adult spinal deformity (ASD) has become common in Japan. This study aimed to clarify the status of surgeries for ASD in Japan, focusing on perioperative complications. A nationwide multicenter survey gathering information on surgically treated ASD patients was conducted by the committee for Adult Spinal Deformity of the Japanese Scoliosis Society. METHODS: This study was a review of retrospectively collected data from 18 spine scoliosis centers belonging to the Japanese Scoliosis Society. Patients who underwent corrective fusion surgery for ASD between 2011 and 2013 were included. Demographics, comorbidities, surgical data, and complications were investigated. RESULTS: A total of 1192 patients (mean age, 57.7 years) were included in this study. Of these, 611 patients were aged less than 65 years and 581 patients were aged 65 years or greater. The age distribution had two peaks, in the third and eighth decades. Deformities caused by degeneration represented 67% of the pathology in patients aged over 65 years; however, non-degenerative disease such as adult idiopathic scoliosis and syndromic or congenital deformity represented over 60% of pathology in patients aged less than 65 years. The iatrogenic deformity and reoperation rates were both less than 3%. The mean operation time and estimated blood loss were 370 min and 1642 ml, respectively. Major perioperative complications occurred in 160 patients (14.5%). The incidence of complications was significantly higher in patients aged over 65 years, including neurological deficits, hemorrhagic shock, hematoma, heart failure, and surgical site infection (p < 0.05). CONCLUSIONS: Older (aged over 65 years) ASD patients showed greater rates of deformity due to the occurrence of degeneration and vertebral fractures, as well as a higher incidence of peri-and postoperative complications. Efforts to reduce perioperative complications are therefore imperative, especially for elderly ASD patients in our aging society.

Cervical myelopathy due to a solitary osteochondroma: a case report.

INTRODUCTION: Osteochondroma is the most common benign bone tumor. However, the incidence of osteochondroma in the spine is reported to be very rare. CASE DESCRIPTION: This report presents the case of a 57-year-old man who suffered from osteochondroma of the cervical spine. He had bilateral lower extremity pain for 3 years, developing pain of right upper extremity and gait disturbance. Plain radiographic images and computed tomography scans showed bony lesion in right C6/7 foramen and C6 lamina. Magnetic resonance images of whole spine showed severe compression of spinal cord at the C6/7 and spinal canal stenosis at the L3/4 level. First, we performed a surgery of the cervical spine, and removed the tumor covered with the cartilaginous cap. The pathological diagnosis of the tumor was osteochodroma. After the surgery, the symptoms on his right upper extremity improved smoothly. Because the bilateral lower extremity pain remained, a L3/4 partial laminectomy was performed 1 month later, and the symptom improved. At 1 year after his primary operation, we could not find a recurrence of the tumor. CONCLUSIONS: It is very important to perform a complete en bloc resection of the tumor (especially cartilaginous cap) to prevent the recurrence.

The relationship between the anatomy of the nuchal ligament and postoperative axial pain after cervical laminoplasty: cadaver and clinical study.

STUDY DESIGN: A cadaver and clinical study investigated the attachment of the nuchal ligament to the cervical spinous process. OBJECTIVE: To investigate the anatomical details of the attachment of the nuchal ligament to the spinous process and the relationship between the morphology of the nuchal ligament and postoperative axial pain after laminoplasty. SUMMARY OF BACKGROUND DATA: The relationship between the length of the C6 spinous process and the morphology of the nuchal ligament and occurrence of postoperative axial pain has not been elucidated. METHODS: The morphology of the nuchal ligament was investigated in 35 cadavers and 60 patients on preoperative computed tomography and magnetic resonance imaging. The lengths of the C6 and C7 spinous processes were measured, and the C6:C7 ratio (C6 spinous process length/C7 spinous process length) was calculated. The relationship between the morphology of the attachment of nuchal ligament to the C6 spinous process and the C6:C7 ratio were investigated. In addition, the effects of the anatomy of the nuchal ligament around the C6 spinous process and different procedures of surgical invasion to C6 or C7 on postoperative axial pain were investigated for 113 patients who underwent laminoplasty. RESULTS: The nuchal ligament was attached to not only the C7 spinous process, but also the C6 spinous process when the C6:C7 ratio was more than 0.8. When the nuchal ligament was attached to the C6 spinous process and to C7, postoperative axial pain after C3-C7 laminoplasty occurred more often compared with C3-C6 laminoplasty for patients without the nuchal ligament attached to the C6 spinous process. CONCLUSION: This study shows that there is an association between the individual anatomical differences of the nuchal ligament and the occurrence of postoperative axial pain after laminoplasty. Careful attention should be paid to the morphology of the attachment of the nuchal ligament to the C6 spinous process to reduce postoperative axial pain.

Adjacent segment degeneration after single-segment PLIF: the risk factor for degeneration and its impact on clinical outcomes.

PURPOSE: To investigate: (1) the risk factors for radiologic cranial adjacent segment degeneration (ASD) after single-segment PLIF at the same level, and (2) the impact of the ASD on the clinical outcomes. METHODS: From October 2004 to May 2009, 109 patients who underwent PLIF for degenerative instability at L4/5 and have more than 2 years follow-up were studied retrospectively. We measured the preoperative bone mineral density (BMD), lumbar lordosis, the lumbosacral joint angle, the lumbar inclination, the height and the dynamic angulation of the intervertebral space at the fused segments and the upper adjacent segment, the sliding displacement between L3 and L4. Clinical outcomes were evaluated using the Japanese Orthopedic Association (JOA) score and the Oswestry Disability Index (ODI). Patients were divided into two groups according to the progression of L3-L4 degeneration: Group A without progression of L3-L4 degeneration, Group B with progression of L3-L4 degeneration. Clinical outcomes and radiologic measurement index between the two groups were compared, and the risk factors for progression of L3-L4 degeneration were analyzed. The correlation between clinical outcomes and progression of L3-L4 degeneration were also investigated. RESULTS: There were 11 patients (22%) classified into Group A. No significant difference was found between the two groups in terms of the lordosis angle at L1 and S1, the laminar inclination at L3, the pre-existing L3-L4 disk degeneration, the lordosis angle of L4-L5, the lumbosacral joint angle and preoperative BMD (P > 0.05). Significant differences were found between the two groups in age. No significant difference was found between the two groups in the ODI and the JOA score at the final follow-up (P > 0.05). CONCLUSION: Radiologic degeneration of the cranial adjacent segment after single-segment PLIF did not significantly correlate with clinical outcomes. Age was a risk factor for radiologic degeneration, however, there was no significant correlation between degeneration and preoperative radiologic factors and bone mineral density (BMD).

Genetic differences in the osteogenic differentiation potency according to the classification of ossification of the posterior longitudinal ligament of the cervical spine.

STUDY DESIGN: We categorized the four types of ossification of the posterior longitudinal ligament (OPLL) of the cervical spine into two groups. We biochemically investigated the genetic differences in the osteogenic differentiation potency between the two groups. OBJECTIVE: To investigate the genetic differences in the osteogenic differentiation potency according to the OPLL classification. SUMMARY OF BACKGROUND DATA: Clinical studies on OPLL have revealed that the risk of progression of the ossification area is greatest for continuous and mixed type OPLL. However, until now, these four types of OPLL have been studied as a single condition. METHODS: We categorized the four types of OPLL into the OPLL continuous (continuous or mixed type) and OPLL segmental groups (segmental or circumscribed type). Paraspinal ligaments were aseptically obtained from OPLL patients during surgery. The fibroblast-like cells that migrated from the explants were used for experiments. The cells were placed in a 60-mm culture dishes for total ribonucleic acid preparation and 12 well microplates for alkaline phosphatase (ALP) activity staining. After cultures reached confluence, the cells were cultured in osteogenic medium. The messenger ribonucleic acid expression of bone morphogenetic protein-2 (BMP-2), osterix, tumor necrosis factor-α-stimulated gene-6, and ALP was analyzed by quantitative real time-polymerase chain reaction. Osteogenic differentiation of fibroblast-like cells was determined by histochemically detecting ALP production. RESULTS: After osteogenic induction, BMP-2 expression increased in the OPLL continuous and segmental groups. Osterix expression increased in the OPLL continuous group only. Tumor necrosis factor-α-stimulated gene-6 expression was suppressed in the OPLL continuous and segmental groups. ALP expression as well as ALP activity staining was higher in the OPLL continuous group than in the OPLL segmental group. CONCLUSION.: The study revealed genetic differences in the osteogenic differentiation potency between the OPLL continuous and segmental groups. We propose to distinguish OPLL continuous group from segmental group in biochemical studies on OPLL.

Surgical outcomes of foramen magnum decompression for syringomyelia associated with Chiari I malformation: relation between the location of the syrinx and body pain.

BACKGROUND: There have been few reports about the relation between the morphology of syrinxes and body pain in syringomyelia associated with Chiari I malformation. To investigate this phenomenon, the relation between the location of the syrinx and body pain before and after foramen magnum decompression (FMD) were evaluated. METHODS: The subjects were 20 patients with Chiari I malformation associated with syringomyelia who underwent FMD. The morphology of the syrinxes was classified into three types - enlarged type, which was a distended syrinx at the central spinal cord; deviated type, which was a deviated syrinx posterolaterally within the spinal cord; central type, which was a small syrinx at the central canal of the spinal cord - based on axial magnetic resonance imaging (MRI). Preoperative and postoperative clinical symptoms and the body pain were evaluated by the Japanese Orthopaedic Association (JOA) score and a visual analogue scale (VAS) prospectively. RESULTS: Preoperative and postoperative JOA scores showed no statistically significant differences between the three syrinx types. Intensity of body pain evaluated by the VAS showed that patients with a deviated-type syrinx on pre- and postoperative MRI tended to be associated with more intense pain than the other two types. CONCLUSIONS: It was indicated that pain before and after surgery is more intense when the syrinx is deviated toward the spinal dorsal horn as seen on MRI.

Preserving the C7 spinous process with its muscles attached: effect on axial symptoms after cervical laminoplasty.

BACKGROUND: Many efforts to reduce axial symptoms after cervical laminoplasty have been tried and reported; nevertheless, avoiding the axial symptoms has not yet been solved. There have been some reports that preserving the muscles attached to the C7 spinous process could reduce axial symptoms. The purpose of this study was to investigate whether axial symptoms can be reduced by preserving the C7 spinous process with its muscles attached during cervical laminoplasty. METHODS: A series of 21 patients (group A) with C4-6 laminoplasty, preserving the C7 spinous process and its attached muscles, were compared with 22 patients (group B) with C4-7 laminoplasty. The axial symptoms (incidence, intensity, severity), cervical mobility, cervical curvature morphology, cross-sectional area of posterior cervical muscles, and Japanese Orthopaedic Association (JOA) score were evaluated. RESULTS: There were no significant differences in incidence, intensity, or severity of axial symptoms 1 year after operation. In addition, there were no significant differences in the cervical mobility or curvature morphology, the cross-sectional area of the posterior cervical muscles, or the JOA score. CONCLUSIONS: These results suggest that both preserving and not preserving the C7 spinous process with its muscles attached during cervical laminoplasty are acceptable in the long term.

A functional RNAi screen for Runx2-regulated genes associated with ectopic bone formation in human spinal ligaments.

Ossification of the posterior longitudinal ligament of the spine (OPLL) is characterized by ectopic ossification in the spinal ligaments, which enlarges with time and compresses the spinal cord, resulting in serious neurological symptoms. We previously reported that Runx2 expression was enhanced in spinal ligament cells from OPLL patients (OPLL cells). To clarify genes regulated by Runx2, Runx2 expression was first enhanced by culturing primary OPLL cells in osteogenic medium (OS induction) and then inhibited by siRNAs targeted to Runx2. DNA microarray demonstrated that in addition to chondrogenic factors such as connective tissue growth factor and cartilage oligomeric matrix protein, angiopoietin-1 was also significantly increased by OS induction and decreased by siRNAs for Runx2 in OPLL cells, suggesting that these genes are regulated by Runx2. However, these changes were not observed in non-OPLL control cells (from cervical spondylotic myelopathy patients). Furthermore, Runx2 was not decreased by siRNAs for angiopoietin-1. OS induction and RNAi inhibition of angiopoietin-1 expression was also observed in osteoblasts. Both siRNAs for Runx2 and angiopoietin-1 completely inhibited aggrecan-1 expression. These results suggest that angiopoietin-1 is downstream of Runx2 in both OPLL primary cells and osteoblasts. Angiopoietin-1 may play an important role in ectopic ossification.

Possible role of extracellular nucleotides in ectopic ossification of human spinal ligaments.

To reveal the involvement of extracellular nucleotides in the ossification process in ossification of the posterior longitudinal ligament of the spine (OPLL), the mRNA expression profiles of P2 purinoceptors, mechanical stress-induced ATP release, and ATP-stimulated expression of osteogenic genes were analyzed in ligament cells derived from the spinal ligament of OPLL patients (OPLL cells) and non-OPLL cells derived from the spinal ligaments of cervical spondylotic myelopathy patients as a control. The extracellular ATP concentrations of OPLL cells in static culture were significantly higher than those of non-OPLL cells, and this difference was diminished in the presence of ARL67156, an ecto-nuclease inhibitor. Cyclic stretch markedly increased the extracellular ATP concentrations of both cell types to almost the same level. P2Y1 purinoceptor subtypes were intensively expressed in OPLL cells, but only weakly expressed in non-OPLL cells. Not only ATP addition but also cyclic stretch raised the mRNA levels of alkaline phosphatase and osteopontin in OPLL cells, which were blocked by MRS2179, a selective P2Y1 antagonist. These increases in the expression of osteogenic genes were not observed in non-OPLL cells. These results suggest an important role of P2Y1 and extracellular ATP in the progression of OPLL stimulated by mechanical stress.

Cervical range of motion and alignment after laminoplasty preserving or reattaching the semispinalis cervicis inserted into axis.

STUDY DESIGN: A radiographic study in 111 patients using radiographs was conducted. OBJECTIVE: To clarify whether the modified laminoplasty with C3 laminectomy preserving the semispinalis cervicis (SSC) inserted into C2 could maintain the postopertive range of motion (ROM) and sagittal alignment compared with conventional C3-C7 laminoplasty reattaching the muscle to C2. SUMMARY OF BACKGROUND DATA: Intraoperative injury of the SSC is relevant to the significant loss of ROM and the malalignment after laminoplasty. To expose the C3 lamina, however, the SSC inserted into C2 could not be preserved in conventional C3-C7 laminoplasty. METHODS: The ROM and sagittal alignment of 70 patients (group A) (52 men, 18 women, mean age 59 y, mean follow-up period 1 y and 7 mo) with C4-C7 laminoplasty with C3 laminectomy were compared with those of 41 patients (group B) (28 men, 13 women, mean age 59 y, mean follow-up period 2 y and 6 mo) with C3-C7 laminoplasty using radiographs of the cervical spine. RESULTS: Regarding C2-C7 ROM, the postoperative ROM was larger (P=0.003) and the decrease rate of ROM was smaller (P=0.0006), and decreased ROM in extension was smaller (P<0.0001) in group A. Regarding O-C2 ROM, the increased ROM was smaller (P=0.043) and increased ROM in extension was smaller (P=0.001) in group A. Regarding O-C7 ROM, the postoperative ROM was larger (P=0.029) in group A. Regarding the cervical alignment, the increased lordotic angle at O-C2 was smaller (P=0.046) in group A. CONCLUSIONS: This modified laminoplasty preserving the SSC inserted into C2 is an effective procedure for maintaining postoperative ROM, especially in extension, and sagittal alignment of the upper cervical spine well.

Cervical spinal motion before and after surgery in patients with Chiari malformation type I associated with syringomyelia.

OBJECT: There have been few reports about the cervical spinal motion in patients with Chiari malformation Type I (CM-I) associated with syringomyelia. To investigate this phenomenon, the relationship between the preoperative cervical range of motion (ROM) and the stage of cerebellar tonsillar descent as well as the cervical ROM before and after foramen magnum decompression (FMD) were evaluated. METHODS: Thirty patients who had CM-I associated with syringomyelia and who underwent FMD participated in the study. The ROM and lordosis angle of the cervical spine were measured on x-ray films. In addition, the relationship between preoperative degree of cerebellar tonsillar descent and the ROM between the levels of the occiput (Oc) and C2 was investigated. RESULTS: The mean flexion-extension ROM at Oc-C2 was 15.5 degrees before and 14.1 degrees after surgery, and the mean flexion-extension ROM of C2-7 was 55.1 degrees before and 52.8 degrees after surgery. The mean pre- and postoperative lordosis angles at C2-7 were 16.8 and 19.1 degrees, respectively. There was no significant difference between the values measured before and after surgery. There was no correlation between the degree of cerebellar tonsillar descent and the ROM at Oc-C2. CONCLUSIONS. Foramen magnum decompression is an excellent surgical technique that has no effect on the postoperative cervical ROM and cervical alignment.

Surgical outcomes in adult patients with syringomyelia associated with Chiari malformation type I: the relationship between scoliosis and neurological findings.

OBJECT: The clinical characteristics of pediatric scoliosis associated with syringomyelia have been reported in previous studies, but scoliosis associated with syringomyelia in adults is rarely treated, and there is a paucity of detailed studies. In the present study of adult syringomyelia associated with Chiari malformation Type I, the authors investigated the relationships among the syrinx, scoliosis, and neurological data. METHODS: The population was composed of 27 patients (> or = 20 years of age) who underwent foramen magnum decompression for the treatment of syringomyelia. The patients were divided into two groups: those with scoliosis of 10 degrees or more (Group A) and those without scoliosis (Group B). The authors assessed the length of the syrinx, duration of morbidity, and clinical status before and after surgery based on the Japanese Orthopaedic Association (JOA) Scale. There were 15 cases in Group A and 12 in Group B. The mean length of the syrinx was 12.8 vertebral bodies (VBs) in Group A and 7.2 VBs in Group B. The mean duration of morbidity was 14.2 years in Group A and 6.8 years in Group B. The mean preoperative JOA score was 10.1 in Group A and 14.4 in Group B, whereas the mean postoperative JOA scores were 11.9 and 15.8, respectively. There were significant differences between Groups A and B in length of the syrinx, duration of morbidity, and pre- and postoperative JOA scores. CONCLUSIONS: In patients with syringomyelia and scoliosis the syringes spanned a greater number of VBs, the duration of morbidity was greater, neurological dysfunction was more severe, and surgical results were poorer. Scoliosis could be a predicting factor of the prognosis in patients with syringomyelia and Chiari malformation Type I.

Preliminary Application of One-level Posterior Lumbar Interbody Fusion with Prospace and Facet Fusion Using Local Autograft / 中国修复重建外科杂志

Objective To evaluate the safety and efficacy of one-level posterior lumbar interbody fusion(PLIF) combined with Prospace and facet fusion using local autograft. Methods Clinical and radiographic data of 76 patients treated by this technique was reviewed from May 2002 to December 2004. Of them, there were 52 males and 24 females, with an average age of 53.2 years (23-81 years), including 60 cases of degenerative disc disease, 9 cases of failed back surgery syndrome and 3 cases of spondylolysis. The disese courses were 1.2-8.7 years (mean 3.6 years). The levels of PLIF were: L2,3 in 2 cases, L3,4 in 7, L4,5 in 54, L5/S1 in 10, L4/S1 in 1 and L5,6 in 2. After decompression, Prospace was inserted into interbody space bilaterally,and located in disc space 4 mm beyond the rear edge of the vertebral body. Local laminectomy autograft was packed both laterally into and between 2 implants. Then the remanent local autograft was placed over facet bed. Pedicle screws were used after insertion of Prospace. Clinical results were evaluated by the JOA score. Disc height ratio and lumbar lordosis angles were measured on lateral radiographs. Fusion status was determined by evidence of bridge trabeculae across facet joint and interbody space on CT scan without mobility in lateral dynamic X-rays, and no radiolucent gap between Prospace and endplate. Paired t-test was used for statistical analysis. Results Mean blood loss and operative time was 384 ml and 178 minutes, respectively. The average JOA score at final follow-up (26.1 + 2.7) was significantly improved when compared with that of pre-operation (14.5 ± 4.0, P ＜ 0.05), with a mean recovery rate of JOA score 81.1% (37.5%-100.0%). The fusion rate was 97.4% (74/76). Mean disc height ratio and the involved segmental lordosis angle were increased from preoperative 0.27 ±0.07 and 5.8 + 2.2° to 0.33 + 0.06 and 11.3 + 2.0° respeetively at the final follow-up, and the differences were significant ( P ＜ 0.05). There were no device-related complications. Conclusion This surgical technique combined with Prospace interbody device is a safe and effective surgical option for patients with one-level lumbar disorders when PLIF is warranted.

Inadvertent C2-C3 union after C1-C2 posterior fusion in adults.

INTRODUCTION: Some authors pointed out that there were more than a few patients with inadvertent C2-C3 union after C1-C2 posterior fusion, although few detailed studies of C2-C3 union have been reported. The purpose of this study was to clarify whether C2-C3 union accelerated adjacent C3-C4 disc degeneration after C1-C2 posterior fusion and to investigate the related factors for C2-C3 union. METHODS: Sixteen patients with rheumatoid arthritis (RA group) (4 males, 12 females, mean age 60 years, mean follow-up period 4 years and 3 months) and fifteen patients without RA (non-RA group) (11 males, 4 females, mean 52 years, mean follow-up period 3 years and 10 months) who underwent C1-C2 posterior fusion were radiologically assessed. The C2-C3 union was defined as trabecular bone formation at C2-C3 interlamina in lateral radiograph. C3-C4 disc height was measured to evaluate the disc degeneration. RESULTS: C2-C3 union rate was 56% and 60% in RA group and non-RA group, respectively. In RA group, postoperative C3-C4 disc height was lower (Student's t-test, P = 0.029) and the decrease rate of C3-C4 disc height was higher (Student's t-test, P = 0.015) in patients with C2-C3 union than in patients without C2-C3 union. In non-RA group, the age at operation was older (Student's t-test, P = 0.0007), and the C1-C2 fusion angle (Student's t-test, P = 0.012) was smaller in patients with C2-C3 union than in patients without C2-C3 union. CONCLUSIONS: C2-C3 union after C1-C2 posterior fusion occurred in more than half of both groups. Inadvertent C2-C3 union should be considered a radiological complication and a potential risk factor due to acceleration of C3-C4 disc degeneration in RA.

Axial symptoms after cervical laminoplasty with C3 laminectomy compared with conventional C3-C7 laminoplasty: a modified laminoplasty preserving the semispinalis cervicis inserted into axis.

STUDY DESIGN: Results of C4-C7 laminoplasty with C3 laminectomy and C3-C7 laminoplasty were compared. OBJECTIVES: To clarify prospectively whether the modified laminoplasty preserving the semispinalis cervicis inserted into C2 could reduce the axial symptoms compared with conventional laminoplasty reattaching the muscle to C2. SUMMARY OF BACKGROUND DATA: Intraoperative damage of the semispinalis cervicis is relevant to the development of axial symptoms after laminoplasty. In C3-C7 laminoplasty, however, it is difficult to preserve the muscle insertion into C2 while opening the C3 lamina. METHODS: The axial symptoms of 40 patients (Group A) with C4-C7 laminoplasty with C3 laminectomy were compared with those of 16 patients (Group B) with C3-C7 laminoplasty. The cross-sectional areas of the cervical posterior muscles were measured on magnetic resonance images. RESULTS: The number of patients with no postoperative axial symptoms increased (P = 0.035) from 19% to 52.5%, and the number of patients whose symptoms worsened after surgery decreased (P = 0.020) from 50% to 17.5%. The average atrophy rate of cross-sectional area was smaller (P < 0.001) in Group A (2.4%) than in Group B (10.8%). CONCLUSIONS: This method was less invasive to the cervical posterior muscles than C3-C7 laminoplasty. This is an effective procedure for preventing postoperative axial symptoms.

Interaction between proteoglycans and alpha-elastin in construction of extracellular matrix of human yellow ligament.

One type of large proteoglycan and three types of small proteoglycans (decorin, decorin-subtype, and biglycan) were purified by chromatography, and alpha-elastin was isolated by alkali treatment from human yellow ligaments taken at the time of operation. The interaction of the proteoglycans with immobilized alpha-elastin on a sensor was analyzed by surface plasmon resonance, and we confirmed that each of the small proteoglycans exhibited a specific binding to alpha-elastin. The binding sites of small proteoglycans were contained in the protein cores. In addition, the differences in the interaction of the small proteoglycans with alpha-elastin of normal and ossified ligaments were compared. The interactions of the small proteoglycans with alpha-elastin of the ossified ligaments were lower than those with alpha-elastin of the normal ligaments. In the ossified ligaments, neodesmosine, one of the cross-linking amino acids, was significantly less than in the normal ligaments (p < .05).

Muscle atrophy after treatment with Halovest.

STUDY DESIGN: A prospective study was conducted on the sequential changes in the muscles around the cervical spine following external fixation for an extended period. OBJECTIVE: Muscular atrophy around the cervical spine following prolonged external fixation with a Halovest and subsequent recovery from the atrophy were examined. SUMMARY OF BACKGROUND DATA: There are a number of reports on the usefulness of the Halovest. However, there have been no descriptions about muscular atrophy following fixation by the Halovest. METHODS: The study participants were 10 patients who were conservatively treated by the Halovest. Imaging by CT was performed periodically following fixation by the Halovest. The cross sections of the sternocleidomastoid muscle and the nuchal muscle group at C5-C6 were computed by using NIH Image Software. The results were used to evaluate muscular atrophy following fixation by the Halovest and the subsequent recovery after removal of the fixation. RESULTS: Following fixation by the Halovest, atrophy of the muscles around cervical spine sequentially progressed. Three months after fixation, muscular atrophy was about 15% at the sternocleidomastoid muscle and 22% for the nuchal muscle group, but the patients recovered from the atrophic state following the removal of the device. CONCLUSION: Following fixation by the Halovest, muscular atrophy around the cervical spine sequentially progressed. After the device was removed, however, the muscles recovered from the atrophic state. Muscular atrophy caused by prolonged fixation by the Halovest was a reversible change.

Nationwide survey on complications of spine surgery in Japan.

The Japan Spine Research Society carried out a nationwide survey on complications of the spine, enrolling a total of 16 157 patients who had undergone spine surgery in 196 institutes in the 1-year period from January to December 2001. Diseases, surgical procedures, and complications were surveyed in detail. Forty-nine percent of patients were aged 60 years or older, which was remarkably increased in comparison with the percentage reported by the 1994 survey (37.3%). The number of cases with degenerative spinal diseases comprised 78.2% of the total number of spine surgery cases. The percentage of patients with stenosis was the greatest (38.5%), reflecting the increase in the elderly population undergoing spine surgery. Spinal instrumentation was used with 5497 patients (34.0%). The frequency of its use was much greater than that reported in 1994 (27.0%). The pedicle screw was the most frequently used instrument (54.6%). The use of spinal instrumentation greatly increased for spinal deformity, trauma, and tumors. Posterior lumbar interbody fusion has been increasingly used in cases of lumbar degenerative disease. Complications of spinal surgery were reported in 1383 patients (8.6%). The incidence of complications associated with instrumentation surgery was 12.1%, being twice as much as that associated with noninstrumentation surgery (6.8%).

Correlation between severity of rheumatoid arthritis and manner and extent of cervical lesion.

Abstract To determine the proper management of treatment for rheumatoid cervical lesions, we investigated the clinical course of the cervical spine in rheumatoid arthritis (RA). The severity of RA was classified into three groups according to the disease subsets advocated by Ochi et al.: the less erosive subset (LES), the more erosive subset (MES), and mutilating disease (MUD). Then the following radiographic assessments were performed on cervical roentogenograms: atlantoaxial subluxation (AAS), vertical subluxation (VS), and subaxial subluxation (SAS). One hundred and seventy-four patients were available for this study. The mean age of the patients was 60.9 years (19-85 years). The average duration from the onset of RA was 19.1 years (10-40 years). Eighty-seven patients were classified as LES, 69 were MES, and 18 were MUD. We found that few patients in the LES group had required an operation on the cervical spine. AAS was seen in about 60% of the MES patients, but few cases had VS or SAS, and most operations were atlantoaxial fusion. All patients in the MUD group had some cervical instabilities. Not only VS but also SAS were seen in more than half of these patients, and many patients had required occipitothoracic fusion.