Comparison of Union Rates Between Autogenous Iliac Crest Bone Graft and Local Bone Graft as Fusion Materials in Lumbar Fusion Surgery: An Evaluation of Up to 3-Level Fusion

OBJECTIVE

To compare the radiologic union rates between autogenous iliac crest bone graft (ICBG) and local bone graft in 1- to 3-level lumbar fusion.

METHODS

We reviewed 178 consecutive patients who underwent 1- to 3-level lumbar fusion surgery because of lumbar spinal stenosis. Fusion status of the anterior or posterior column was evaluated by plain radiographs obtained at 24 months postoperatively. If at least either the anterior or posterior column was fused, that segment was regarded as having achieved fusion and was termed segment union. The definition of overall union was achieving union of all segments in a single patient.

RESULTS

For each ICBG group and local bone graft group, fusion rate of the anterior and posterior column, and rate of the segments and overall union at postoperative 2 years were not different between the groups, regardless of surgery level. In the overall union rate according to the fusion level, the ICBG group showed constant overall fusion rate according to the fusion level (i.e., 96.9%, 96.9%, and 93.1% for 1-, 2-, and 3-level fusion), but tended to decrease with increasing level in the local bone graft group (100%, 95.8%, and 85.7% for 1-, 2-, and 3-level fusion, respectively) without statistically significant differences.

CONCLUSIONS

The union rate of 3-level fusion was not inferior to those of 1- or 2-level fusion in both ICBG and local bone graft patients. Local bone graft could be regarded as an adequate option for not only 1- or 2-level lumbar fusion but also 3-level lumbar fusion surgery.

Transforaminal epidural steroid injections in cervical spinal disease with moderate to severe disability: Comparative study in patients with or without surgery

Despite many clinical trials on cervical epidural steroid injections, the indications for and long-standing outcomes of this treatment remain controversial. We evaluated the outcomes and indications for transforaminal cervical epidural steroid injection (TCESI) in patients with moderate to severe disability.We prospectively gathered data from patients with 1 or 2-level cervical degenerative disease (herniated disc, foraminal stenosis) with moderate to severe disability (3.5 < initial visual analog scale < 6.5, 15 < Neck Disability Index < 35) and greater than 12 weeks of pain, despite conservative treatment. Patients with persistent disability and those who desired surgical intervention underwent decompression surgery. The clinical and demographic characteristics were compared between groups.Of the 309 patients who underwent TCESI, 221 (72%) did not receive surgical treatment during the 1-year follow-up period. The remaining 88 patients (28%) underwent surgery at a mean of 4.1 months after initial TCESI. Patients who underwent injection alone showed a significant decrease in disability and pain that persisted until the 1-year follow-up visit (P < .05). In patients who underwent surgery, the mean disability and pain scores after injection did not decrease for several months, although the scores significantly decreased up to 1 year after surgery (P < .05).The TCESI significantly decreased pain and disability in the moderate to severe disability group up to 1 year after injection. We recommend cervical TCESI as an initial treatment with moderate to severe disability patients.

Delayed presentation of infected common iliac artery pseudoaneurysm caused by malpositioned pedicle screw after minimally invasive scoliosis surgery

PURPOSE

To report delayed onset common iliac artery perforation and infected pseudoaneurysm caused by malpositioned pedicle screw after minimally invasive scoliosis surgery (MISS).

METHODS

A 21-year-old female was referred to our hospital with a 1-week history of abrupt right-sided low back pain, lower abdominal pain, and fever with a history of MISS using cannulated pedicle screws 18 months earlier. Paravertebral arterial erosion with pseudoaneurysm and retroperitoneal and paraspinal abscess were suspected.

RESULTS

We performed resection of the pseudoaneurysm, vascular repair of right common iliac artery by angioplasty with a bovine patch and removal of implant. At 6 months after the last surgery, she had no limitations or problems in her daily activities with no recurrence of low back pain, abdominal pain, or fever as well as without loss of deformity.

CONCLUSIONS

Our case showed that misplaced pedicle screws can cause potentially fatal complications, such as infected pseudoaneurysm, even in the late postoperative period.

Impact of ankylosing spondylitis on depression: a nationwide cohort study

The aim of this study is to determine the relationship between AS and subsequent depression. This study was conducted using a nationwide dataset available in Korean National Health Insurance System (KNHIS). We identified 11,465 newly diagnosed AS patients and 57,325 patients without AS in the ratio of 1:5 matched by sex, age, and index date, between 2010 and 2014. We investigated any latent characteristics in the patients’ demographic information and chronic comorbidities that could trigger a depression when diagnosed with AS. By comparing the cohort data, the hazard ratio of developing subsequent depression in AS patients was calculated and adjusted based on several risk factors. Despite the adjustment of demographic variables and chronic comorbidities, the risk of depression was 2.21 times higher in the AS cohort than in the control group. Multivariate analysis showed that AS patients with female gender, old age and low-income status showed higher risks of developing depression. Additionally, the presence of chronic comorbidities including diabetes mellitus, hypertension, hyperlipidemia, cancer, stroke, and chronic kidney disease increased the patients’ risk of depression. The AS patients with stroke were reported to have the highest risk of depression. This population-based cohort study showed that AS significantly increased the subsequent risk of developing depression. Moreover, the development of a depression is influenced by certain demographic variables and different chronic comorbidities.

Relationship between dementia and ankylosing spondylitis: A nationwide, population-based, retrospective longitudinal cohort study

Among a variety of comorbidities of ankylosing spondylitis (AS), the association between dementia and AS by using an extensive dataset from the Korean National Health Insurance System was evaluated in this study. We extracted 15,547 newly diagnosed AS subjects among the entire Korean population and excluded wash-out patients (n = 162) and patients that were inappropriate for cohort match (n = 1192). Finally, 14,193 subjects were chosen as the AS group, and through 1:5 age- and sex-stratified matching, 70,965 subjects were chosen as the control group. We evaluated patient demographics, household incomes, and comorbidities, including hypertension, diabetes, and dyslipidemia. The prevalence of overall dementia (1.37%) and Alzheimer’s dementia (AD) (0.99%) in the AS group was significantly higher than in the control group (0.87% and 0.63%), respectively. The adjusted hazard ratio of the AS group for overall dementia (1.758) and AD (1.782) showed statistical significance also. On the other hand, the prevalence of vascular dementia did not differ significantly between the two groups. Subgroup analyses revealed the following risk factors for dementia in the AS group: male gender, greater than 65 years in age, fair income (household income greater than 20% of the median), urban residency, no diabetes, and no hypertension. From the nationwide, population-based, retrospective, longitudinal cohort study, AS patients showed a significantly higher prevalence of overall dementia and Alzheimer’s dementia. Comprehensive patient assessment using our subgroup analysis could help to prevent dementia in patients suffering from AS.

Analysis of sensory system aspects of postural stability during quiet standing in adolescent idiopathic scoliosis patients

Background

The aim of this study was to quantitatively analyze quite standing postural stability of adolescent idiopathic scoliosis (AIS) patients in respect to three sensory systems (visual, vestibular, and somatosensory).

Method

In this study, we analyzed the anterior-posterior center of pressure (CoP) signal using discrete wavelet transform (DWT) between AIS patients (n = 32) and normal controls (n = 25) during quiet standing.

Result

The energy rate (∆E_EYE%) of the CoP signal was significantly higher in the AIS group than that in the control group at levels corresponding to vestibular and somatosensory systems (p < 0.01).

Conclusions

This implies that AIS patients use strategies to compensate for possible head position changes and spinal asymmetry caused by morphological deformations of the spine through vestibular and somatosensory systems. This could be interpreted that such compensation could help them maintain postural stability during quiet standing. The interpretation of CoP signal during quiet standing in AIS patients will improve our understanding of changes in physical exercise ability due to morphological deformity of the spine. This result is useful for evaluating postural stability before and after treatments (spinal fusion, bracing, rehabilitation, and so on).

Trends in the prevalence and incidence of ankylosing spondylitis in South Korea, 2010-2015 and estimated differences according to income status

The aim of this study is to determine the prevalence and incidence of ankylosing spondylitis (AS) in South Korea, 2010–2015. This study was conducted using the Health Insurance Review Agency (HIRA) database, which includes information on every patient diagnosed with AS. The incidence and prevalence of AS were evaluated by age, sex, and income status. The prevalence increased linearly by 7.7% annually, i.e., 31.62 in 2010 to 52.30 in 2015 (per 100,000 persons). During the study period, the incidence was 6.34 per 100,000 person-years. The prevalence peaked for both men and women in the age range 30–39 years. Incidence peaked for men in the age range 20–29 years, but peaked for women between ages 70 and 89. AS was 3.6 times more prevalent in men than in women, and the incidence in men was 2.1 times greater than in women. With respect to income status, the prevalence and incidence of AS were 3 times greater and 5 times greater, respectively, in medical aid recipients compared to individuals with other income levels. The trend of increasing AS prevalence and the observation that 14.3% of all patients newly diagnosed with AS are medical aid recipients have significant implications for healthcare planning.

Acetylcholine precursor, citicoline (cytidine 5'-diphosphocholine), reduces hypoglycaemia-induced neuronal death in rats

Citicoline (cytidine 5'-diphosphocholine) is an important precursor for the synthesis of neuronal plasma membrane phospholipids, mainly phosphatidylcholine. The administration of citicoline serves as a choline donor for the synthesis of acetylcholine. Citicoline has been shown to reduce the neuronal injury in animal models with cerebral ischaemia and in clinical trials of stroke patients. Citicoline is currently being investigated in a multicentre clinical trial. However, citicoline has not yet been examined the context of hypoglycaemia-induced neuronal death. To clarify the therapeutic impact of citicoline in hypoglycaemia-induced neuronal death, we used a rat model with insulin-induced hypoglycaemia. Acute hypoglycaemia was induced by i.p. injection of regular insulin (10 U kg^-1 ) after overnight fasting, after which iso-electricity was maintained for 30 minutes. Citicoline injections (500 mg/kg, i.p.) were started immediately after glucose reperfusion. We found that post-treatment of citicoline resulted in significantly reduced neuronal death, oxidative injury and microglial activation in the hippocampus compared to vehicle-treated control groups at 7 days after induced hypoglycaemia. Citicoline administration after hypoglycaemia decreased immunoglobulin leakage via blood-brain barrier disruption in the hippocampus compared to the vehicle group. Citicoline increased choline acetyltransferase expression for phosphatidylcholine synthesis after hypoglycaemia. Altogether, the present findings suggest that neuronal membrane stabilisation by citicoline administration can save neurones from the degeneration process after hypoglycaemia, as seen in several studies of ischaemia. Therefore, the results suggest that citicoline may have therapeutic potential to reduce hypoglycaemia-induced neuronal death.

Fractional curve progression with maintenance of fusion mass in congenital scoliosis: An 18-year follow-up of a case report

RATIONALE

The management of congenital scoliosis concentrates on early diagnosis and proper surgical treatment before the development of severe deformities. Decision making regarding the appropriate fusion levels, proper surgical treatment, and reduction amount of kyphoscoliosis is very important but difficult in the treatment of congenital scoliosis, especially in young children.

PATIENT CONCERNS

We report an 11-year follow-up of revision surgery for fractional curve progression after combined anterior and posterior fusion without hemivertebra resection using pedicle screw fixation (PSF) in congenital kyphoscoliosis at age 4 years (a total 18-year follow-up). A T12 hemivertebra was documented in a 4-year-old girl and was treated by combined anterior and posterior fusion in two stages with PSF. The fusion mass was maintained but the distal compensatory curve progressed during the follow-up period. The patient underwent a posterior vertebral column resection (PVCR) with extended posterior fusion at the age of 11, 7 years after initial surgery.

OUTCOMES

Eleven years after the revision surgery with PVCR, the patient showed satisfactory results and her spine was well balanced.

LESSONS

The cause of revision surgery for the curve progression may include inappropriate fusion level, incomplete hemivertebra resection, or failure of anterior and posterior fusion. Especially, inappropriate fusion level may result in deterioration of the compensatory curve even without progression of the fusion mass.

CONCLUSION

Appropriate selection of fusion levels, complete resection of hemivertebra, and satisfactory reduction of scoliosis and kyphosis are important factors for deformity correction and prevention of progression of both main and compensatory curves (adding-on of structural curve or progression of compensatory curve) as well as reducing the influence of adjacent vertebral growth using as short a fusion as possible.

Efficacy of cortico/cancellous composite allograft in treatment of cervical spondylosis

This was a prospective comparative study.The aim of this study was to compare the clinical and radiologic outcomes of patients treated with cortico/cancellous composite allograft or autoiliac bone graft in anterior cervical discectomy and fusion.Several methods have been developed to fuse the cervical spine for treatment of cervical spondylosis. Cortico/cancellous composite allograft might be another alternative.A total of 46 patients who underwent surgery for treatment of cervical spondylosis were evaluated between September 2010 and January 2015. The duration of operation, blood loss, perioperative complications, neck disability index (NDI), visual analogue scale (VAS), and fusion rates were compared between the 2 groups.There were no significant differences in clinical or radiologic outcomes between the patients treated with cortico/cancellous composite allograft and those treated with autoiliac bone graft. The 2 groups showed similar improvements in clinical symptoms and fusion rates. Although not statistically significant, the subsidence rate was lower in the cortico/cancellous composite group.Cortico/cancellous composite allograft is an effective alternative to conventional allograft or autograft in anterior cervical discectomy and fusion.

Relationship between bone mineral density and alcohol intake: A nationwide health survey analysis of postmenopausal women

OBJECTIVES

Among a variety of relevant factors of osteoporosis, the association between alcohol intake and postmenopausal women's bone mineral density (BMD) by using data from the Korean National Health and Nutrition Examination Survey was evaluated in this study.

MATERIALS AND METHODS

Among a total of 31,596 subjects, males, premenopausal women, participants without BMD data were excluded. Finally, a total number of subjects in the study was 3,312. The frequency and amount of alcohol intake were determined by self-reported questionnaires, and BMD was measured by dual-energy x-ray absorptiometry.

RESULTS

Mean femoral BMD for light drinkers was statistically significantly greater than that for heavy drinkers and non-drinkers. We observed the characteristic trends for BMD by drinking frequency; the mean BMD gradually increased from non-drinkers to the participants who drank 2-3 times per week; these participants exhibited the highest BMD. Participants who drank alcohol greater than 4 times per week showed a lower BMD. In the risk factor analysis, the adjusted odds ratio for osteoporosis (at femoral neck) was 1.68 in non-drinkers and 1.70 in heavy drinkers compared with light drinkers.

CONCLUSIONS

Light alcohol intake (2-3 times per week and 1-2 or 5-6 glasses per occasion) in South Korean postmenopausal women was related to high femoral BMD. Non-drinkers and heavy drinkers had approximately a 1.7-times greater risk for osteoporosis than light drinkers.

Prevalence of symptomatic hip, knee, and spine osteoarthritis nationwide health survey analysis of an elderly Korean population

Osteoarthritis is prominent among the elderly, with symptoms originating from multiple parts of the body. A cross-sectional study of a nationwide survey was performed to describe the prevalence of and identify factors related to symptomatic hip, knee, and spine osteoarthritis.This cross-sectional study collected data from the Fifth Korean National Health and Nutrition Examination Survey (KNHANES V-5; 2010-2012). After excluding ineligible subjects, there were 8976 subjects in this study (3830 males and 5146 females). All subjects reported symptoms and disabilities related to osteoarthritis. Plain radiographs of the spine, hip, and knee were taken in all subjects.Overall, 9.3% of male participants and 28.5% of female participants were diagnosed with symptomatic osteoarthritis according to survey criteria. Women showed a significantly higher prevalence in all age groups (P < 0.05). Multiple-joint osteoarthritis was diagnosed in 10.8% of male patients and 22.8% of female patients with osteoarthritis. Several demographic and lifestyle variables were related to osteoarthritis morbidity. Anthropometric and laboratory measurements were also related to osteoarthritis morbidity. In addition, mental distress and quality of life were significantly compromised in osteoarthritis. There were more significant relationships for these factors among women with a higher prevalence of multijoint osteoarthritis.A significant proportion of the elderly with single- or multiple-joint osteoarthritis had a variety of pain origins that were closely related. Osteoarthritis was also significantly related to several factors, including mental distress and quality of life.

Revision surgery for curve progression after implant removal following posterior fusion only at a young age in the treatment of congenital scoliosis: A case report

RATIONALE

Congenital scoliosis due to a hemivertebra creates a wedge-shaped deformity, which progresses and causes severe spinal deformities as an individual grows. The treatment of congenital scoliosis focuses on early diagnosis and appropriate surgical management before the development of severe deformity.

PATIENT CONCERNS

We report the case of a 4-year-old male child with a left thoracolumbar scoliosis of 27° (T10-T12) due to a T11 hemivertebra who was treated by posterior fusion and pedicle screw fixation at the age of 4 years. The implant was removed due to pain secondary to implant prominence after 4 years without definitive revision surgery, which led to significant progression of the scoliosis, to 50°. The indication for posterior vertebral column resection (PVCR) is a congenital spinal deformity with a curve magnitude greater than 30° with fast progression. This includes documented progression of the curve by more than 5° in a 6- month period, failure of conservative treatment, or both.

OUTCOMES

The patient underwent PVCR of the T11 hemivertebra. Nine years after the revision surgery with PVCR, the patient showed satisfactory results and his spine was well balanced.

LESSONS

This case shows that removal of an implant that was not the only cause of curve progression at a young age may lead to progression of scoliosis and, therefore, should be avoided unless it is absolutely necessary.

CONCLUSION

Congenital scoliosis due to a hemivertebra at a young age could be treated by hemivertebra resection or anterior and posterior epiphysiodesis as definitive surgical treatment. The patient was eventually treated with PVCR, which achieved satisfactory correction without curve progression in a long-term follow-up.

Congenital scoliosis treated with posterior vertebral column resection in patients younger than 18 years: longer than 10-year follow-up

OBJECTIVE

There have been no reports on the long-term radiographic outcomes of posterior vertebral column resection (PVCR) in patients with congenital scoliosis. The purpose of this study was to evaluate the surgical outcomes and complications after PVCR and its long-term effects on correcting this deformity in children with congenital scoliosis.

METHODS

The authors retrospectively analyzed the medical records of 45 patients with congenital scoliosis who were younger than 18 years at the time of surgery and who underwent PVCR and fusion with pedicle screw fixation (PSF). The mean age of the patients at the time of surgery was 11.3 years (range 2.4–18.0 years), and the mean length of follow-up was 12.8 years (range 10.1–18.2 years).

RESULTS

The mean Cobb angle of the main curve was 46.5° before PVCR, 13.7° immediately after PVCR, and 17.6° at the last follow-up. For the compensatory cranial curve, PVCR corrected the preoperative Cobb angle of 21.2° to 9.1° postoperatively and maintained it at 10.9° at the last follow-up. For the compensatory caudal curve, the preoperative Cobb angle of 23.8° improved to 7.7° postoperatively and was 9.8° at the last follow-up. The authors noted 22 complications, and the overall incidence of complications was 48.9%.

CONCLUSIONS

Posterior vertebral column resection is an effective procedure for managing congenital scoliosis in patients younger than 18 years. Use of PVCR and fusion with PSF for congenital scoliosis achieved rigid fixation and satisfactory deformity correction that was maintained over the long term. However, the authors note that PVCR is a technically demanding procedure and entails risks for major complications and excessive blood loss.

What Is the Role of Epidural Steroid Injections in Lumbar Spinal Disease with Moderate Disability?

Epidural steroid injections have been gaining popularity as an alternative to surgical treatment of radicular pain with associated spinal derangement. To determine the effectiveness and indications of lumbar epidural steroid injections in patients with or without surgery, we performed a prospective observational study. We gathered data from 262 degenerative short-segment spinal disease patients (affected at one or 2 levels) with greater than 12 weeks of medication-resistant radicular pain without neurological deficits but with moderate disability (visual analog scale < 6.5; Oswestry Disability Index < 35). All patients received initial fluoroscopically guided transforaminal epidural steroid injections of the affected vertebral level(s) corresponding to their symptoms. Those with inadequate responses or who wanted subsequently surgery underwent decompression surgery. Clinical and demographic characteristics were assessed to compare the differences between the groups.

RESULTS

Of the 262 patients who received epidural steroid injections, 204 did not have operations for up to one year. However, 58 patients experienced inadequate relief of pain or wanted operations and therefore underwent surgery. At baseline, the 2 groups had similar mean disability indices and pain scores, as well as gender ratios, ages, and durations of symptoms (P > 0.05). In the patients who underwent surgery, the mean disability and pain scores were not significantly decreased after injection compared to those in the injection-alone group, although the scores for the injection plus surgery patients decreased significantly after surgery (P < 0.05). In contrast, patients who underwent epidural steroid injection alone experienced a significant decrease in disability and pain after injection, and that persisted up to one year of follow-up (P < 0.05). Epidural steroid injection can decrease the pain and disability in the majority of a moderate disability group for up to one year, although a significant number of patients underwent surgery regardless of injection. We recommend epidural steroid injection as a first-line treatment in patients with moderate disability that can be converted to surgery without significant delay.

KEY WORDS

Epidural steroid injection, spinal surgery, lumbar spinal disease, lumbar radiculopathy, lumbar radicular pain.

Congenital Kyphoscoliosis in Monozygotic Twins: Ten-Year Follow-up Treated by Posterior Vertebral Column Resection (PVCR): A Case Report

The etiology of congenital scoliosis and its development remains unclear and has not yet been fully identified, even there are theories that congenital scoliosis could be derived from the failure of formation or failure of segmentation, which are etiologically heterogeneous with genetic, epigenetic, and environmental factors contributing to their occurrence. We reported a case of long-term follow-up after posterior vertebral column resection (PVCR) in both identical twins with similar congenital kyphoscoliosis at thoracolumbar levels. Twin I had been noticed by his parents to have asymmetry of his back at age 5 years, but no treatment was given. Twin II was first noticed to have a spinal problem at 11 years of age by his parents. Overtime, spine of both twins became further deviated to the left with kyphosis and was referred to our hospital. Both monozygotic twins were treated by PVCR and satisfactory results were demonstrated at 10-year follow-up.This case is the first report on the surgical treatment with PVCR, almost simultaneously, in both identical twins who had similar congenital vertebral anomalies causing kyphoscoliosis. Both identical twins with congenital kyphoscoliosis had undergone surgical correction by PVCR, anterior support with a mesh cage and posterior fusion using pedicle screws at the age of 14 years and achieved a satisfactory correction and a stable spine without curve progression with 10-year follow-up.

Internal herniation due to an omphalomesenteric duct cyst in a 69-year-old man

Previous abdominal surgery is the most common cause of mechanical small bowel obstruction. However, in patients with no history of abdominal surgery, the diagnosis and treatment of mechanical small bowel obstruction is difficult. A persistent omphalomesenteric duct remnant is a rare finding that typically presents in the pediatric population and is extremely rare in patients aged > 60 years. In the present report, we describe the case of an omphalomesenteric duct cyst causing small bowel obstruction in a 69-year-old man with no history of a surgical procedure.

Analysis of hip dysplasia and spinopelvic alignment in cerebral palsy

BACKGROUND CONTEXT

Knowledge of sagittal spinopelvic parameters and hip dysplasia is important in cerebral palsy (CP) patients because these parameters differ from those found in the general population and can be related to symptoms.

PURPOSE

The purpose of this study was to analyze sagittal spinopelvic alignment and determine its relation to hip dysplasia in CP patients.

STUDY DESIGN

Radiological analysis was conducted on patients with CP.

PATIENT SAMPLE

Fifty-four patients with CP and 24 normal controls were included in this study.

OUTCOME MEASURES

Participants underwent radiographs of the whole spine.

METHODS

The patient and control groups comprised 54 CP patients and 24 volunteers, respectively. All underwent lateral radiography of the whole spine and hip joint anteroposterior radiography. The radiographic parameters examined were sacral slope, pelvic tilt, pelvic incidence, S1 overhang, thoracic kyphosis, thoracolumbar kyphosis, lumbar lordosis, sagittal balance, center edge angle, acetabular angle, and migration index. Statistical analysis was performed to identify significant differences and correlations between the two groups.

RESULTS

Sacral slope, thoracolumbar kyphosis, lumbar lordosis, sagittal balance, acetabular angle, and migration index were significantly higher in CP patients, whereas pelvic tilt, S1 overhang, and center edge angle were significantly lower (p<.05). Correlation analysis revealed that pelvic incidence, sacral slope, pelvic tilt, and S1 overhang were related to each other and that thoracolumbar kyphosis was related to the thoracic kyphosis and lumbar lordosis (p<.05). For spinal and pelvic parameters, lumbar lordosis was related to sacral slope, pelvic incidence, pelvic tilt, and S1 overhang; for hip dysplasia parameters, center edge angle and acetabular angle were found to be interrelated (p<.05). Regarding symptoms, pelvic tilt, S1 overhang, and thoracolumbar kyphosis were found to be correlated with symptom severity in patients. However, no hip dysplasia parameters were found to be related to hip or spinal symptoms.

CONCLUSIONS

This study found significant differences between CP patients and normal controls in terms of spinopelvic alignment and hip dysplasia. Furthermore, relationships were found between the sagittal spinopelvic parameters and hip dysplasia, and correlations were found between sagittal spinopelvic parameters and pain.

Optimal condition of heparin-conjugated fibrin with bone morphogenetic protein-2 for spinal fusion in a rabbit model

BACKGROUND AIMS

Heparin-conjugated fibrin (HCF) is a carrier for long-term release of bone morphogenetic protein-2 (BMP-2) and has been shown to promote bone formation in animal models. We performed an experimental study to determine the optimal dose of BMP-2 with an HCF carrier that promotes bone formation comparable to that of autograft while minimizing complications in spinal fusion.

METHODS

Twenty-four rabbits underwent posterolateral fusion of the L5-6 spinal segments. Different concentrations of HCF BMP-2 (1/10, 1/20, 1/30 or 1/40) were implanted in the spines of experimental rabbits, and autograft or INFUSE was implanted in the spines of control animals. Eight weeks after treatment, spinal fusion efficacy was evaluated by plain radiography, micro-computed tomography (micro-CT), mechanical testing and histomorphometry.

RESULTS

Similar to autograft, the 1/40 HCF BMP-2 showed significant bone formation on micro-CT and histomorphometry with mechanical stability. However, the other HCF BMP-2 concentrations did not show significant bone formation compared with autograft. Although conventional BMP-2 (INFUSE) led to higher bone formation and stability, it also led to excessive ectopic bone and fibrous tissue formation.

CONCLUSIONS

This study suggests the optimal concentration of BMP-2 using HCF for spinal fusion, which may decrease the complications of high-dose conventional BMP-2.

Clinical anatomy of vertebrae in scoliosis: global analysis in four different diseases by multiplanar reconstructive computed tomography

BACKGROUND CONTEXT

Few accurate analyses of clinically useful vertebral anatomy have been conducted, and most have focused on thoracic idiopathic scoliosis.

PURPOSE

To evaluate the different anatomic characteristics in scoliosis by disease type and level.

STUDY DESIGN

Observational cohort study.

PATIENT SAMPLE

Forty-eight patients with scoliosis were included in this study.

OUTCOME MEASURES

Subjects underwent computed tomography (CT) of the whole spine.

METHODS

Forty-eight patients with scoliosis were included in this study: 15 adolescent idiopathic, 11 cerebral palsy (CP), 10 muscular dystrophy (MD), and 12 congenital (CG) scoliosis patients with similar demographics. Subjects underwent CT of the whole spine, preoperatively. Eight anatomic parameters were measured in multiplanar reconstructive CT images, and statistical analysis was performed to investigate differences.

RESULTS

In general, values in the anatomic parameters were similar for the four diseases. Each parameter showed the unique change pattern according to the spinal level regardless of curvature shape, direction, or magnitude. In particular, chord length (CL) in MD and CG scoliosis was lower than in adolescent idiopathic scoliosis (AIS) and CP, and pedicle rib unit length was lower in CG scoliosis than in the other diseases (p<.05). Comparisons of convex and concave anatomies in AIS showed that inner pedicle width (PWI) and outer pedicle width (PWO) were wider for convex side, CL, pedicle width, and transverse pedicle angle were greater for concave side (p<.05), and differences were more significant at apices. However, in CP, PWI and PWO were similar between convex and concaves sides (p>.05). Although PWI and PWO were wider for convex sides and CL and pedicle length were greater for concave sides in MD (p<.05), differences were less significant at apices. Particularly, CG scoliosis showed severely deformed anatomy, with differences of seven parameters at apical vertebrae (p<.05).

CONCLUSION

Clinical anatomies of vertebrae in scoliosis were found to differ significantly at different levels and in terms of convexity and disease type.

Analysis of sagittal spinopelvic parameters in cerebral palsy

BACKGROUND CONTEXT

Knowledge of sagittal spinopelvic parameters is important for the treatment of cerebral palsy (CP) because they differ in the normal population and can induce symptoms.

PURPOSE

To analyze the sagittal spinal alignment and the pelvic orientation in CP.

STUDY DESIGN

Radiological analysis of patients with CP.

METHODS

The study and control groups comprised 57 CP patients and 24 healthy volunteers, respectively. All the patients underwent lateral radiography of the whole spine including hip joints. The radiographic parameters examined were sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), S1 overhang (OH), thoracic kyphosis (TK), thoracolumbar kyphosis (TLK), lumbar lordosis (LL1 and 2), and sagittal balance (SB). Statistical analysis was performed to identify the significant differences between the two study groups. In addition, correlations were sought between the parameters and symptoms.

RESULTS

The PT and OH were significantly smaller in the CP patients, whereas SS, TLK, LL1, LL2, and SB were significantly greater (p<.05). Correlation analysis revealed significant relationships between the sagittal parameters. Specifically, PI was found to be associated with SS, PT, and OH, whereas the spinal parameters LL1 and LL2 were found to be related to TK and SB. Between spine and pelvic parameters, LL1 and LL2 were found to be related to SS, PT, PI, and OH and in addition, SB was found to be related to TLK, LL1, and LL2. An analysis of relations between the symptoms and parameters revealed a positive correlation between the severities of symptoms and PT, OH, and TLK (r=0.300, p=.023; r=0.306, p=.020; r=0.289, p=.029, respectively).

CONCLUSIONS

A significant difference was observed in the sagittal spinopelvic parameters in the CP and normal control groups and was possibly related to the symptoms. The study shows that the evaluations of sagittal spinopelvic parameters could be useful during the treatment of disorders associated with CP.

Extraction of three-dimensional information of biological membranous tissue with scanning confocal infrared laser microscope tomography

The "LEXT" confocal laser scanning microscope has been used for the three-dimensional (3D) imaging of the surface of specimens, especially in materials science fields, by the penetration of near-infrared (NIR) light without mechanical cutting, deposition, or other specimen pretreatment. Noninvasive investigation of various biological tissues such as human spinal dura mater, rat aorta, and cornea without the dehydration process was successfully carried out with the "LEXT," in order to access both surface and internal topographic images of the biological structures at a good status of the wet tissue such as in vivo, especially in measuring tissue thickness. The confocal NIR laser microscopy offers the viable means to visualize tissue architecture and its thickness in microdomain to integrate 3D images efficiently. We believe that the "LEXT" has a good application for biological researchers to study biomaterials, and it would be useful as a diagnostic tool in the near future.

Centroid method: an alternative method of determining coronal curvature in scoliosis. A comparative study versus Cobb method in the degenerative spine

BACKGROUND CONTEXT

Although the Cobb method is considered the gold standard, the centroid method may offer a reasonable alternative in adult scoliosis because it has better inter- and intraobserver reliabilities in adolescent scoliosis.

PURPOSE

To compare the reliabilities of the Cobb and the centroid methods for measuring coronal curvature in degenerative scoliosis in older patients.

STUDY DESIGN

Observational study involving three examiners.

PATIENT SAMPLE

Sixty whole spine posteroanterior (PA) radiographs were collected.

OUTCOME MEASURES

Data were analyzed to determine inter- and intraobserver reliabilities.

METHODS

Sixty whole spine PA radiographs of patients older than 60 years were collected to compare the reliabilities of the centroid and the Cobb methods for measuring coronal curvature in degenerative scoliosis. Three examiners using both methods independently measured radiographs twice. Data were analyzed to determine inter- and intraobserver reliabilities.

RESULTS

Intraobserver comparisons of all the 60 radiographs revealed that inter- and intraclass correlation coefficients (ICCs) of the Cobb and the centroid methods were both excellent (greater than 0.979 vs. greater than 0.918), and mean absolute differences (MADs) were similar (less than 1.58 vs. less than 2.02). In interobserver comparisons, ICCs of the Cobb method were higher than that of the centroid method (greater than 0.922 vs. greater than 0.799), and the MADs of the Cobb method were lower than that of the centroid method (less than 2.91 vs. less than 4.84). Comparisons of radiographs subdivided by severity showed that the ICCs of the Cobb and the centroid methods were both excellent (greater than 0.819 vs. greater than 0.801), and their MADs were similar (less than 2.29 vs. less than 2.53) for intraobserver comparisons. Interobserver comparisons showed that ICCs and MADs were dependent on the severity of coronal curvature, and the ICCs of the Cobb method (greater than 0.698) were greater than that of the centroid method (greater than 0.507). Furthermore, MAD values for the Cobb method were lower than that for the centroid method (less than 3.59 vs. less than 6.07). Moreover, these results are contradictory to the previous study, which showed the higher reliability of the centroid method in measures of adolescent scoliosis.

CONCLUSIONS

In the present study, the reliability of the centroid method was found to be more susceptible to the severity of disease in older patients, despite its demonstrated greater reliability in adolescent scoliosis. Our findings show that the selective use of these two methods in old and young patients can increase the reliabilities of measurements made.

Analysis of factors that affect shoulder balance after correction surgery in scoliosis: a global analysis of all the curvature types

PURPOSE

To identify factors that can affect postoperative shoulder balance in AIS.

METHOD

89 adolescent idiopathic scoliosis patients with six types of curvatures who underwent surgery were included in this study. Whole spine antero-posterior and lateral radiographs were obtained pre- and postoperatively. In radiograms, shape and changes in curvatures were analyzed. In addition, four shoulder parameters and coronal balance were analyzed in an effort to identify factors significantly related to postoperative shoulder balance.

RESULT

In general, all the four shoulder parameters (CHD, CA, CRID, RSH) were slightly increased at final follow up (t test, P < 0.05), although there was a decrease in Lenke type II and IV curvatures. However, pre- and postoperative shoulder parameters were not significantly different between each curvature types (ANOVA, P > 0.05). Moreover, no significant differences of pre- and postoperative shoulder level between different level of proximal fusion groups (ANOVA, P > 0.05) existed. In the analysis of coronal curvature changes, no difference was observed in every individual coronal curvatures between improved shoulder balance and aggravated groups (P > 0.05). However, the middle to distal curve change ratio was significantly lower in patients with aggravated shoulder balance (P < 0.05). In addition, patients with smaller preoperative shoulder imbalance showed the higher chance of aggravation after surgery with similar postoperative changes (P < 0.05).

CONCLUSIONS

Significant relations were found between correction rate of middle, and distal curvature, and postoperative shoulder balance. In addition, preoperative shoulder level difference can be a determinant of postoperative shoulder balance.

Paraganglioma in the cauda equina. A case report

Paraganglioma of the cauda equina is rare, and diagnosis is difficult. A 47-year-old woman presented with backache, with a 2-year history of pain radiating in her right lower extremity. Initial neurologic examination revealed mild hypaesthesia in the L4 dermatome on both sides. Spine MRI showed a well-delinated intradural extramedullary mass compressing the spinal cord. It extended from L2 to L4, with anterior compression of the spinal cord which was displaced posteriorly. Clinical and radiological findings suggested an ependymoma. Surgical decompression was performed from L2 to L4 through lumbar laminectomy under microscope. Intraoperatively, the patient experienced unexplained paroxysmal hypertension while manipulating the tumour, which was not relieved by hypotensive medication but resolved immediately after resection of the mass. Postoperatively, the neurologic status improved and the radiating pain was relieved. Histopathologic examination showed cellular perivascular arrangement which looked like 'pseudorosettes'. Taken together, these histologic and radiologic findings suggested a benign myxopapillary ependymoma. However, immunohistochemical examination showed reactivity with synaptophysin and chromogranin. Finally, histological examination of the specimen revealed a 'Zellballen' pattern of paraganglioma, and the final diagnosis of paraganglioma with secreting function was confirmed. Paraganglioma is a rare tumour that can exhibit a secreting function causing paroxysmal hypertension which may be life threatening. Therefore, the differential diagnosis is important. The diagnosis is based on close examination of the clinical, radiologic and pathologic findings.

Analysis of dural sac thickness in human spine-cadaver study with confocal infrared laser microscope

BACKGROUND CONTEXT

The thickness of the human spine dural sac can show differences between individuals and levels, and these differences can alter clinical outcomes.

PURPOSE

To analyze spinal cord dural sac thicknesses.

STUDY DESIGN

Anatomical study of human cadavers.

METHODS

The subjects of this study were 19 human cadavers with no prior history of spinal surgery or deformity. Seventeen specimens from T1/T2 to L5/S1 were obtained from each of 19 cadavers, a total of 323 specimens. Multiple sections were prepared from these specimens. Microscopic measurements were taken with an infrared laser-based confocal microscope to determine the mean dural sac thickness at each level. In addition, a magnetic resonance image of the lumbar spine was obtained from each subject. Relations between dural sac thicknesses at different levels were analyzed with respect to gender, age, and stenosis level.

RESULTS

Overall mean dural sac thickness was 0.307±0.122 mm in this human cadaver series. Dura thicknesses differed significantly at different levels (p=.046). Overall, dural thickness was highest at T9/T10 and lowest at L2/L3 (p=.0007) as well as highest at the lower thoracic level followed by the upper thoracic and lumbar levels (p=.003). In addition, dural sac thickness was found to increase slightly but significantly with age (p=.019). However, dural thickness was similar between men and women (p=.123). And, no significant dural thickness differences were found for stenotic and nonstenotic lesions (p=.885).

CONCLUSION

Dural sac thickness was found to be significantly dependent on spinal level and age in human cadavers. An appreciation of dural sac thickness differences can be useful in the clinical field, and it is hoped that this encourages further study of dural physiology.

The effects of spinal cord injury induced by shortening on motor evoked potentials and spinal cord blood flow: an experimental study in Swine

BACKGROUND

Spinal cord injury due to spinal shortening is disastrous, but the amount that the spine can be shortened without injury is unknown. We assessed spinal cord injury and changes in spinal cord blood flow after spinal shortening in swine.

METHODS

Ten pigs underwent pedicle screw instrumentation between T10 and T13 followed by a T11 and T12 vertebrectomy resulting in spinal shortening. Spinal cord function and spinal cord blood flow were monitored simultaneously with use of transcranial motor evoked potentials and laser Doppler flowmetry, respectively. A staged shortening procedure was performed: phase 1 resulted in no morphological change in the spinal cord, phase 2 resulted in buckling of the spinal cord, and phase 3 resulted in kinking of the spinal cord. After loss of motor evoked potential signals, which was considered to indicate spinal cord injury, the spinal instrumentation was tightened. The motor evoked potentials and spinal cord blood flow were monitored for an additional thirty minutes, and a wake-up test was then performed. Finally, a spinal cord specimen was obtained and evaluated histologically.

RESULTS

The motor evoked potential data demonstrated no evidence of spinal cord injury during phases 1 and 2. However, the signals were lost during phase 3, indicating spinal cord injury. The mean shortening was 35 ± 2.7 mm, which was similar to the mean vertebral body height at the thoracolumbar level (33.6 ± 1.9 mm), indicating that spinal cord injury resulted from shortening equivalent to the height of one vertebra. Spinal shortening did not cause injury if the amount of shortening was less than the mean segmental height of the entire spinal column (27.7 ± 1.6 mm for T1-L6). The spinal cord blood flow increased slightly (by 11.6% ± 20.6%) during phase 2, but decreased by 43.1% ± 11.4% during phase 3. The wake-up test performed after thirty minutes revealed no movement in the lower limbs.

CONCLUSIONS

Spinal shortening of =104.2% of one vertebral body height at the thoracolumbar level caused spinal cord injury, but shortening of =73.8% did not result in injury. swine.

Correlation between facial asymmetry, shoulder imbalance, and adolescent idiopathic scoliosis

We conducted a prospective cross-sectional study to examine the correlation between facial asymmetry, shoulder imbalance, and adolescent idiopathic scoliosis. Sixty-nine adolescent idiopathic scoliosis patients and 29 healthy volunteers were enrolled in this study. All patients underwent whole-spine standing anteroposterior radiographs and frontal cephalograms. Patients were divided into mild, moderate, and severe groups depending on Cobb angle (10°-25°, 25°-40°, and >40°, respectively). Facial measurements included maxilla height difference, ramus length difference, and anterior nasal spine-menton angle. Shoulder measurements included coracoid height difference, clavicular angle, clavicle-rib intersection difference, and radiographic shoulder height.The anterior nasal spine-menton angle in the severe group (>40°) was higher than in the other groups (P<.05), as was the clavicle-rib intersection difference (P<.05). In addition, the magnitude of the curve showed a possible correlation with the anterior nasal spine-menton angle and clavicle-rib intersection difference in scoliosis patients (r=0.433 and r=0.511, respectively). According to different curve patterns, the anterior nasal spine-menton angle and clavicle-rib intersection difference were significantly higher in the double thoracic group than in the other groups (P<.05). In the correlation analysis, the ramus length difference and anterior nasal spine-menton angle had a possible correlation with the coracoid height difference, clavicular angle, radiographic shoulder height, and clavicle-rib intersection difference (P<.05).

Changes in level of the conus after corrective surgery for scoliosis: MRI-based preliminary study in 31 patients

BACKGROUND

Detection of postoperative spinal cord level change can provide basic information about the spinal cord status, and electrophysiological studies regarding this point should be conducted in the future.

METHODS

To determine the changes in the spinal cord level postoperatively and the possible associated factors, we prospectively studied 31 patients with scoliosis. All the patients underwent correction and posterior fusion using pedicle screws and rods between January 2008 and March 2009. The pre- and postoperative conus medullaris levels were determined by matching the axial magnetic resonance image to the sagittal scout image. The patients were divided according to the change in the postoperative conus medullaris level. The change group was defined as the patients who showed a change of more than one divided section in the vertebral column postoperatively, and the parameters of the change and non-change groups were compared.

RESULTS

The mean pre- and postoperative Cobb's angle of the coronal curve was 76.80° ± 17.19° and 33.23° ± 14.39°, respectively. Eleven of 31 patients showed a lower conus medullaris level postoperatively. There were no differences in the pre- and postoperative magnitude of the coronal curve, lordosis and kyphosis between the groups. However, the postoperative degrees of correction of the coronal curve and lumbar lordosis were higher in the change group. There were also differences in the disease entities between the groups. A higher percentage of patients with Duchenne muscular dystrophy had a change in level compared to that of the patients with cerebral palsy (83.3% vs. 45.5%, respectively).

CONCLUSIONS

The conus medullaris level changed postoperatively in the patients with severe scoliosis. Overall, the postoperative degree of correction of the coronal curve was higher in the change group than that in the non-change group. The degrees of correction of the coronal curve and lumbar lordosis were related to the spinal cord level change after scoliosis correction.

Preoperative predictors of postoperative pulmonary complications in neuromuscular scoliosis

BACKGROUND

Neuromuscular scoliosis (NMS) is associated with progressive restrictive lung disease and an increased risk of prolonged ventilation following surgery. This study reports the experiences of a single institution and evaluates whether preoperative pulmonary function tests (PFT) can predict the development of postoperative pulmonary complications.

METHODS

Correlations between preoperative PFT (forced expired volume in 1 s, FEV(1); forced vital capacity, FVC) findings and postoperative pulmonary complications were searched for among 74 NMS patients who underwent surgical correction at our medical center from 2002 to 2008.

RESULTS

Thirty-seven patients (50%) developed a pulmonary complication. The independent factors found to contribute to the development of a pulmonary complication were: FEV(1) <40% of the predicted value (P = 0.007), FVC <39.5% of the predicted value (P = 0.005), a larger Cobb angle (>69°) (P = 0.002), and older age (>16.5 years) (P = 0.027). Of these 37 patients, 6 needed postoperative ventilation. PFT findings found to be independently associated with the need for postoperative ventilation were: FEV(1) <40% of the predicted value (P = 0.017) and FVC <39.5% of the predicted value (P = 0.015).

CONCLUSIONS

NMS patients with a preoperative FVC of <39.5% of the predicted value, an FEV(1) <40% of the predicted value, a Cobb angle of >69°, or age >16.5 years were found to be more likely to develop a postoperative pulmonary complication.

Maggot debridement therapy for postsurgical wound infection in scoliosis: a case series in five patients

STUDY DESIGN

Case series of 5 patients who developed resistant wound infection after scoliosis surgery.

OBJECTIVE

To present maggot debridement therapy (MDT) as an effective alternative to the conventional treatment in postsurgical infection in scoliosis.

SUMMARY OF BACKGROUND DATA

Numerous clinical reports have been published that describe outstanding effects of MDT, most notable on debridement, cleansing, disinfection, and healing of indolent wounds, many of which have previously failed to respond to conventional treatment. However, till date no reports have been found in the literature describing its use for the treatment of wound infection after scoliosis surgery, which has relatively longer and deeper wound.

METHODS

A total of 5 patients (2 females and 3 males) who developed wound infection after scoliosis correction surgery were included in this study. All were operated for neuromuscular scoliosis using posterior approach with pedicle screw fixation. All developed deep wound infection within 2 to 6 weeks of surgery, which was resistant to all kinds of conventional therapy. MDT applied in all using prepared commercially available maggot bags, and dressing was changed twice a week till wound shows signs of healing. After confirming negative culture, MDT was stopped and routine dressings or secondary closure was done. During the treatment, wound appearance, size, and development of healing were observed.

RESULTS

There were 1 patient with paralytic scoliosis and 4 with cerebral palsy. All wound healed completely within 5.2 ± 1.8 weeks of MDT or 8.8 ± 3.8 cycles of MDT. There was no recurrence on final follow-up of 21.6 ± 5.9 months. Wound size was also decreased from 24.2 ± 3.3 cm of pre-MDT to 11.8 ± 4.5 cm post-MDT showing 51.2% reduction in wound size. There was partial implant removal in 2 cases before MDT; however, no further implant extraction was needed in any case after MDT. Treatment was tolerated well by all patients without any obvious complications due to MDT.

CONCLUSION

We would propose to use MDT for the treatment of wound infection after scoliosis surgery as an effective alternative to conventional treatment. In this way, implant extraction could be avoided without losing any correction.

Idiopathic scoliosis in Korean schoolchildren: a prospective screening study of over 1 million children

Cross-sectional epidemiologic scoliosis screening was carried out to determine the current prevalence of scoliosis in the Korean population and to compare with the results of previous studies. Between 2000 and 2008, 1,134,890 schoolchildren underwent scoliosis screening. The children were divided into two age groups, 10-12-year-olds (elementary school) and 13-14-year-olds (middle school), to calculate age- and sex-specific prevalence rates. Children with a scoliometer reading ≥5° were referred for radiograms. Two surgeons independently measured curve types, magnitudes, and Risser scores (inter-observer r = 0.964, intra-observer r = 0.978). Yearly and overall prevalence rates of scoliosis were calculated. There were 584,554 boys and 550,336 girls in the sample, with a male to female ratio of 1.1:1. There were 77,910 (6.2%) children (26,824 boys and 51,086 girls) with scoliometer readings >5°, and 37,339 of them had positive results with Cobb angles ≥10° (positive predictive value, 46.4%). The overall scoliosis prevalence rate was 3.26%; girls had a higher prevalence (4.65%) than boys (1.97%). Prevalence rates increased progressively from 1.66 to 6.17% between 2000 and 2008, with the exception of 2002. According to age and gender, 10-12-year-old girls had the highest scoliosis prevalence rates (5.57%), followed by 13-14-year-old girls (3.90%), 10-12-year-old boys (2.37%), and 13-14-year-old boys (1.42%). In girls and boys, prevalence rates dropped by 64.53 and 60.65% among 10-12-year-olds and 13-14-year-olds, respectively (P = 0.00). The proportion of 10°-19° curves was 95.25 and 84.45% in boys and girls, respectively; and the proportion of 20°-29° curves was 3.91 and 11.28%, which was a significant difference (P = 0.00). Thoracic curves were the most common (47.59%) followed by thoracolumbar/lumbar (40.10%), double (9.09%), and double thoracic (3.22%) curves. A comparison of the curve patterns revealed significant differences between genders (P = 0.00). We present this report as a guide for studying the prevalence of idiopathic scoliosis in a large population, and the increasing trend in the prevalence of idiopathic scoliosis emphasizes the need for awareness.

Magnetic resonance imaging study determining cord level and occupancy at thoracolumbar junction in achondroplasia - A prospective study

BACKGROUND

Thoracolumbar (TL) stenosis in achondroplasia is frequently reported, and becomes symptomatic in adulthood. Hence we conducted a prospective study to determine cord level and occupancy at TL junction in symptomatic or asymptomatic achondroplasis patients in comparision to normal population by magnetic resonance imaging (MRI).

MATERIALS AND METHODS

Cord level with its occupancy rate and TL kyphosis were measured on MRI and standing radiogram, respectively. We prospectively studied MRI of TL spine in 19 patients (7 males and 12 females) with achondroplasia. All the subjects were randomly selected from our outpatient clinic and divided into two groups: symptomatic and asymptomatic group. Symptomatic group had at least two of the following symptoms: back pain with spasticity and walking difficulty, radicular pain in upper thigh or girdle pain, tingling and numbness in the lower limbs, visible deformity at TL spine and brisk reflexes in lower extremities. Asymptomatic group was selected from those patients who visited in outpatient clinic for consultation of limb lengthening. The third group was taken as control that comprised 11 nonachondroplasia otherwise normal patients (8 males and 3 females) who presented to our outpatient clinic for back pain.

RESULTS

Results showed spinal cord level was higher in achondroplasia than nonachondroplasia (P=0.003); however, no difference in cord level between symptomatic and asymptomatic group (P=0.568). Comparing cord occupancy, no difference found among all three groups (P=0.20). Kyphosis was increasing from nonachondroplasia, asymptomatic and symptomatic patient groups (P<0.001). Average age was 22.4±14.2, 11.9±6.5, and 36.2±13.2 years in symptomatic, asymptomatic, and nonachondroplasia groups, respectively (P<0.001).

CONCLUSION

Our results indicated high level of spinal cord in achondroplasia patients compared to nonachondroplasia individuals. High prevalence of neurological symptoms at TL level in such patients can be associated with high cord level and developing progressive kyphosis at TL level along with degenerative process.

Spontaneous regression of curve in immature idiopathic scoliosis - does spinal column play a role to balance? An observation with literature review

Background

Child with mild scoliosis is always a subject of interest for most orthopaedic surgeons regarding progression. Literature described Hueter-Volkmann theory regarding disc and vertebral wedging, and muscular imbalance for the progression of adolescent idiopathic scoliosis. However, many authors reported spontaneous resolution of curves also without any reason for that and the rate of resolution reported is almost 25%. Purpose of this study was to question the role of paraspinal muscle tuning/balancing mechanism, especially in patients with idiopathic scoliosis with early mild curve, for spontaneous regression or progression as well as changing pattern of curves.

Methods

An observational study of serial radiograms in 169 idiopathic scoliosis children (with minimum follow-up one year) was carried. All children with Cobb angle < 25° and who were diagnosed for the first time were selected. As a sign of immaturity at the time of diagnosis, all children had Risser sign 0. No treatment was given to entire study group. Children were divided in three groups at final follow-up: Group A, B and C as children with regression, no change and progression of their curves, respectively. Additionally changes in the pattern of curve were also noted.

Results

Average age was 9.2 years at first visit and 10.11 years at final follow-up with an average follow-up of 21 months. 32.5% (55/169), 41.4% (70/169) and 26% (44/169) children exhibited regression, no change and progression in their curves, respectively. 46.1% of children (78/169) showed changing pattern of their curves during the follow-up visits before it settled down to final curve. Comparing final fate of curve with side of curve and number of curves it did not show any relationship (p > 0.05) in our study population.

Conclusion

Possible reason for changing patterns could be better explained by the tuning/balancing mechanism of spinal column that makes an effort to balance the spine and result into spontaneous regression or prevent further progression of curve. If this which we called as "tuning/balancing mechanism" fails, curve will ultimately progress.

The protective effects of interleukin-18 and interferon-γ on neuronal damages in the rat hippocampus following status epilepticus

To elucidate whether interleukin-18 (IL-18) or interferon-γ (IFN-γ) participates in neurodegeneartion, we investigated the changes in IL-18 and IFN-γ systems within the rat hippocampus following status epilepticus (SE). In non-SE induced animals, IL-18, IL-18 receptor α (IL-18Rα), IFN-γ and IFN-γ receptor α (IFN-γRα) immunoreactivity was not detected in the hippocampus. Following SE, IL-18 immunoreactivity was increased in CA1-3 pyramidal cells as well as dentate granule cells. IL-18 immunoreactivity was also up-regulated in astrocytes and microglia/macrophages. IL-18Rα immunoreactivity was detected in astrocytes and microglia/macrophages. IFN-γ immunoreactivity was detected only in astrocytes within all regions of the hippocampus. IFN-γRα immunoreactivity was increased in neurons as well as astrocytes. Intracerebroventricular infusions of recombinant rat IL-18 or IFN-γ alleviated SE-induced neuronal damages, while neutralization of IL-18, IFN-γ or their receptors aggravated them, as compared to saline-infused animals. These findings suggest that astroglial-mediated IFN-γ pathway in response to IL-18 induction may play an important role in alleviation of SE-induced neuronal damages.

Intraoperative blood loss during different stages of scoliosis surgery: A prospective study

BACKGROUND

There are a number of reasons for intraoperative blood loss during scoliosis surgery based on the type of approach, type of disease, osteopenia, and patient blood profile. However, no studies have investigated bleeding patterns according to the stage of the operation. The objective of this prospective study was to identify intraoperative bleeding patterns in different stages of scoliosis surgery.

METHODS

We prospectively analyzed the estimated blood loss (EBL) and operation time over four stages of scoliosis surgery in 44 patients. The patients were divided into three groups: adolescent idiopathic (group 1), spastic neuromuscular (group 2) and paralytic neuromuscular (group 3). The per-level EBL and operation times of the groups were compared on a stage-by-stage basis. The bone marrow density (BMD) of each patient was also obtained, and the relationship between per-level EBL and BMD was compared using regression analysis.

RESULTS

Per-level operation time was similar across all groups during surgical stage (p > 0.05). Per-level EBL was also similar during the dissection and bone-grafting states (p > 0.05). However, during the screw insertion stage, the per-level EBL was significantly higher in groups 2 and 3 compared to group 1 (p < 0.05). In the correction stage, per-level EBL was highest in group 3 (followed in order by groups 2 and 1) (p < 0.05). Preoperative BMD indicated that group 3 had the lowest bone quality, followed by groups 2 and 1 (in order), but the preoperative blood indices were similar in all groups. The differences in bleeding patterns in the screw insertion and correction stages were attributed to the poor bone quality of groups 2 and 3. Group 3 had the lowest bone quality, which caused loosening of the bone-screw interface during the correction stage and led to more bleeding. Patients with a T-score less than -2.5 showed a risk for high per-level EBL that was nine times higher than those with scores greater than -2.5 (p = 0.003).

CONCLUSIONS

We investigated the blood loss patterns during different stages of scoliosis surgery. Patients with poor BMD showed a risk of blood loss nine times higher than those with good BMD.

Epidural cement leakage through pedicle violation after balloon kyphoplasty causing paraparesis in osteoporotic vertebral compression fractures - a report of two cases

Kyphoplasty is advantageous over vertebroplasty in terms of better kyphosis correction and diminished risk of cement extravasations. Literature described cement leakage causing neurological injury mainly after vertebroplasty procedure; only a few case reports show cement leakage with kyphoplasty without neurological injury or proper cause of leakage. We present a report two cases of osteoporotic vertebral compression fracture treated with kyphoplasty and developed cement leakage causing significant neurological injury. In both cases CT scan was the diagnostic tool to identify cause of cement leakage. CT scan exhibited violation of medial pedicle wall causing cement leakage in the spinal canal. Both patients displayed clinical improvement after decompression surgery with or without instrumentation. Retrospectively looking at stored fluoroscopic images, we found that improper position of trocar in AP and lateral view simultaneously while taking entry caused pedicle wall violation. We suggest not to cross medial pedicle wall in AP image throughout the entire procedure and keeping the trocar in the center of pedicle in lateral image would be the most important precaution to prevent such complication. Our case reports adds the neurological complications with kyphoplasty procedure and suggested that along with other precautions described in the literature, entry with trocar along the entire procedure keeping the oval shape of pedicle in mind (under C-arm) will probably help to prevent such complications.

Accuracy of thoracic pedicle screw using ideal pedicle entry point in severe scoliosis

BACKGROUND

The ideal pedicle entry point for the thoracic spine is described as the base of the superior facet at the junction of the lateral and middle thirds of the pedicle. Investigators have reported its accuracy in curves less than 90 degrees .

QUESTIONS/PURPOSES

Our aim was to measure the accuracy of this entry point for pedicle screw insertion in severe and rigid scoliotic curves.

PATIENTS AND METHODS

We retrospectively measured the accuracy of thoracic pedicle screws in 26 patients with severe and rigid scoliosis (Cobb angle > or = 90 degrees ) inserted using the free-hand technique and the ideal pedicle entry point. Placements of thoracic pedicle screws were reviewed on postoperative CT scans, and the incidence and severity of penetration were determined. Screws penetrating medially up to 2 mm and laterally up to 4 mm were considered within the safe zone.

RESULTS

One hundred sixty-eight (34.8%) of 482 inserted screws breached pedicle walls; 64 (13.2%) and 104 (21.6%) screws breached pedicle walls medially and laterally, respectively. Four hundred thirty-seven screws were within the safe zone, representing an accuracy rate of 90.7%. The accuracy rates of inserted screws in upper, middle, and lower thoracic pedicles were 93.4%, 87.7%, and 92%, respectively.

CONCLUSIONS

Use of the ideal pedicle entry point is safe and accurate for thoracic pedicle screw placement in rigid curves of 90 degrees or greater.

LEVEL OF EVIDENCE

Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Structure of ribulose-1,5-bisphosphate carboxylase-oxygenase: Form III crystals

A new crystal form (III) of tobacco leaf ribulosebisphosphate carboxylase [3-phospho-D-glycerate carboxy-lyase (dimerizing), EC 4.1.1.39] has been grown by dialysis procedures, and is suitable for structural studies at near atomic resolution. The crystals exhibit birefringence, grow as pseudo-regular rhombic dodecahedrons, and belong to the tetragonal space group P4(2)2(1)2 with a = b = 149 A, c = 138 A, and V = 3.04 x 10(6) A(3). Each unit cell contains two molecules, with two large and two small subunits per asymmetric unit. At low resolution (>10 A) the crystal structure is body centered belonging to space group 1422 with one large/small pair in the asymmetric unit. Thus, at low resolution the molecular symmetry is D(4), the highest possible symmetry for an oligomer of stoichiometry large(8)small(8). Form III crystals may be identical to crystalline inclusions found in chloroplasts.

Treatment and complications in flaccid neuromuscular scoliosis (Duchenne muscular dystrophy and spinal muscular atrophy) with posterior-only pedicle screw instrumentation

Literature has described treatment of flaccid neuromuscular scoliosis using different instrumentation; however, only one article has been published using posterior-only pedicle screw fixation. Complications using pedicle screws in paralytic neuromuscular scoliosis has not been described before. To present results and complications with posterior-only pedicle screws, a retrospective study was carried out in 27 consecutive patients with flaccid neuromuscular scoliosis (Duchenne muscular dystrophy and spinal muscular atrophy), who were operated between 2002 and 2006 using posterior-only pedicle screw instrumentation. Immediate postoperative and final follow-up results were compared using t test for Cobb angle, pelvic obliquity, thoracic kyphosis and lumbar lordosis. Perioperative and postoperative complications were noted from the hospital records of each patient. Complications, not described in literature, were discussed in detail. Average follow-up was 32.2 months. Preoperative, immediate postoperative and final follow-up Cobb angle were 79.8 degrees , 30.2 degrees (63.3% correction, p < 0.0001) and 31.9 degrees , respectively; and pelvic obliquity was 18.3 degrees , 8.9 degrees (52% correction, p < 0.0001) and 8.9 degrees . Postoperative thoracic kyphosis remained unchanged from 27.6 degrees to 19.9 degrees (p = 0.376); while lumbar lordosis improved significantly from +15.6 degrees to -22.4 degrees lordosis (p = 0.0002). Most patients had major to moderate improvement in postoperative functional and ambulatory status compared to the preoperative status. Thirteen (48.1%) perioperative complications were noted with five major complications (four respiratory in the form of hemothorax or respiratory failure that required ventilator support and one death) and eight minor complications (three UTI, two atelectasis, two neurological and one ileus). Postoperatively, we noted complications, such as coccygodynia with subluxation in 7, back sore on the convex side in 4 and dislodging of rod distally in 1 patient making a total of 12 (44.4%) postoperative complications. Of 12 postoperative complications, 6 (50%) required secondary procedure. We conclude that although flaccid neuromuscular scoliosis can be well corrected with posterior-only pedicle screw, there is a high rate of associated complications.

Grade 4 spondylolisthesis of the L5 vertebra associated with dural ectasia in neurofibromatosis

Spondylolisthesis associated with neurofibromatosis is rare, and only 12 cases have been reported so far. However, only one report of grade 4 spondylolisthesis with neurofibromatosis has been reported in the literature. A 15-year-old boy with neurofibromatosis was admitted for back pain and neurological claudication. Radiograph showed grade 4 spondylolisthesis of the L5 vertebra with scalloping of the L4-L5 vertebrae. L4-L5 laminectomy, reduction, L3-S1 posterior instrumentation and fusion were performed. The reduction of the spondylisthesis was done entirely from the posterior approach using pedicle screws. Radiography at four months showed a broken S1 screw with a loss of reduction. The patient was re-operated on, to provide additional stability with pelvic fixation. He was pain-free with a good fusion at the two-year follow-up. Adequate posterior stabilisation with fusion gives good results in grade 4 spondylolisthesis associated with neurofibromatosis and dural ectasia.

Surgical complications in neuromuscular scoliosis operated with posterior- only approach using pedicle screw fixation

Background

There are no reports describing complications with posterior spinal fusion (PSF) with segmental spinal instrumentation (SSI) using pedicle screw fixation in patients with neuromuscular scoliosis.

Methods

Fifty neuromuscular patients (18 cerebral palsy, 18 Duchenne muscular dystrophy, 8 spinal muscular atrophy and 6 others) were divided in two groups according to severity of curves; group I (< 90°) and group II (> 90°). All underwent PSF and SSI with pedicle screw fixation. There were no anterior procedures. Perioperative (within three months of surgery) and postoperative (after three months of surgery) complications were retrospectively reviewed.

Results

There were fifty (37 perioperative, 13 postoperative) complications. Hemo/pneumothorax, pleural effusion, pulmonary edema requiring ICU care, complete spinal cord injury, deep wound infection and death were major complications; while atelectesis, pneumonia, mild pleural effusion, UTI, ileus, vomiting, gastritis, tingling sensation or radiating pain in lower limb, superficial infection and wound dehiscence were minor complications. Regarding perioperative complications, 34(68%) patients had at least one major or one minor complication. There were 16 patients with pulmonary, 14 with abdominal, 3 with wound related, 2 with neurological and 1 cardiovascular complications, respectively. There were two deaths, one due to cardiac arrest and other due to hypovolemic shock. Regarding postoperative complications 7 patients had coccygodynia, 3 had screw head prominence, 2 had bed sore and 1 had implant loosening, respectively. There was a significant relationship between age and increased intraoperative blood loss (p = 0.024). However it did not increased complications or need for ICU care. Similarly intraoperative blood loss > 3500 ml, severity of curve or need of pelvic fixation did not increase the complication rate or need for ICU. DMD patients had higher chances of coccygodynia postoperatively.

Conclusion

Although posterior-only approach using pedicle screw fixation had good correction rate, complications were similar to previous reports. There were few unusual complications like coccygodynia.

Treatment of neuromuscular scoliosis with posterior-only pedicle screw fixation

Background

To determine whether posterior-only approach using pedicle screws in neuromuscular scoliosis population adequately addresses the correction of scoliosis and maintains the correction over time.

Methods

Between 2003 and 2006, 26 consecutive patients (7 cerebral palsy, 10 Duchenne muscular dystrophy, 5 spinal muscular atrophy and 4 others) with neuromuscular scoliosis underwent posterior pedicle screw fixation for the deformity. Preoperative, immediate postoperative and final follow-up Cobb's angle and pelvic obliquity were analyzed on radiographs. The average age of the patients was 17.5 years (range, 8–44 years) and the average follow-up was 25 months (18–52 months).

Results

Average Cobb's angle was 78.53° before surgery, 30.70° after surgery (60.9% correction), and 33.06° at final follow-up (57.9% correction) showing significant correction (p < 0.0001). There were 9 patients with curves more than 90° showed an average pre-operative, post operative and final follow up Cobb's angle 105.67°, 52.33° (50.47% correction) and 53.33° (49.53% correction) respectively and 17 patients with curve less than 90° showed average per operative, post operative and final follow up Cobb's angle 64.18, 19.24(70% correction) and 21.41(66.64 correction); which suggests statistically no significant difference in both groups (p = 0.1284). 7 patients underwent Posterior vertebral column resection due to the presence of a rigid curve. The average spinal-pelvic obliquity was 16.27° before surgery, 8.96° after surgery, and 9.27° at final follow-up exhibited significant correction (p < 0.0001). There was 1 poliomyelitis patient who had power grade 3 in lower limbs pre-operatively, developed grade 2 power post-operatively and gradually improved to the pre-operative stage. There was 1 case of deep wound infection and no case of pseud-arthrosis, instrument failures or mortality.

Conclusion

Results indicate that in patients with neuromuscular scoliosis, acceptable amounts of curve correction can be achieved and maintained with posterior-only pedicle screw instrumentation without anterior release procedure.

Development of genu varum in achondroplasia: relation to fibular overgrowth

Genu varum in the achondroplastic patient has a complex and multifactorial aetiology. There is little mention in the literature of the role of fibular overgrowth. Using the ratio of fibular to tibial length as a measurement of possible fibular overgrowth, we have related it to the development of genu varum. Full-length standing anteroposterior radiographs of 53 patients with achondroplasia were analysed. There were 30 skeletally-immature and 23 skeletally-mature patients. Regression analysis was performed in order to determine if there was a causal relationship between fibular overgrowth and the various indices of alignment of the lower limb. Analysis showed that the fibular to tibial length ratio had a significant correlation with the medial proximal tibial angle and the mechanical axial deviation in the skeletally-immature group. We conclude that there is a significant relationship between fibular overgrowth and the development of genu varum in the skeletally-immature achondroplastic patient.

Bone age delay patterns in Legg-Calvé-Perthes disease: an analysis using the Tanner and Whitehouse 3 method

To study the bone age delay patterns in different stages of Perthes disease, 140 hand and corresponding hip radiographs in 83 patients were assessed. In the hand radiographs, the radius, ulna, metacarpals and phalanges (RUS) and carpal bone ages were calculated using the Tanner and Whitehouse 3 method and the Greulich and Pyle (G and P) bone age was assessed using the G and P atlas. From corresponding hip radiographs, the modified Elizabethtown stage was assessed. The RUS and carpal bone age as well as G and P bone age were found to lag behind the chronological age. The 95% confidence interval for the difference between RUS and G and P bone ages was 0.19 to 0.43 years and between carpal and G and P bone ages was -0.516 to -0.14 years, indicating a close agreement between the Tanner and Whitehouse 3 and G and P methods. The RUS bone age delay was maximum in stage Ia (2.00 +/- 1.08 years), whereas carpal delay was maximum in stage IIa (2.15 +/- 1.28 years). Bone maturation acceleration was observed in later stages of the disease as bone age tried to catch up with chronological age. Carpal delay was significantly greater than RUS delay from stage Ib to IIIb (P<0.05), but no significant difference was observed between carpal and RUS delays in stage IV (P=0.21), implying that bone maturation acceleration occurs in the RUS in the earlier stages, and carpal bone age tends to catch up with RUS bone age in the healed stage of the disease. The RUS and carpal bone age delays in stage I were significantly greater in severe (Catterall groups 3 and 4) disease than in mild (Catterall groups 1 and 2) disease. All patients in whom RUS or carpal bone age delay in stage I was greater than 2 years subsequently developed severe disease, indicating a positive correlation between bone age delay in stage I and subsequent extent of involvement of capital femoral epiphysis.

Bifocal tibial corrective osteotomy with lengthening in achondroplasia: an analysis of results and complications

The results and complications of bifocal tibial osteotomies with gradual correction and lengthening by Ilizarov ring fixator performed in 47 tibiae in 24 achondroplastic patients were analyzed. Comparison was made between the parameters of angular and torsional deformities of the tibia preoperatively, at fixator removal, and at last follow-up. Of these parameters, statistically significant change was seen postoperatively in the values of medial proximal tibial angle, lateral distal tibial angle, mechanical axis deviation, and tibial torsion, which changed from 78.8 +/- 7.05 degrees, 103.2 +/- 11.8 degrees, 25.1 +/- 14.6 mm (medial), and 22.7 +/- 10 degrees (internal) preoperatively to 87.3 +/- 6.3 degrees, 90.9 +/- 5.4 degrees, 5.3 +/- 10 cm (medial), and 15.8 +/- 4.2 degrees (external), respectively, at the time of fixator removal; and this correction was maintained during the follow-up period. Mean total tibial lengthening was 6.84 +/- 1.3 cm. Average healing index was 26.06 days/cm. Complications observed were 15 pin tract infections, 1 residual varus, 1 overcorrection into valgus, 2 recurrence of varus, 22 equinus contractures, 2 premature consolidations, and 3 fibula malalignments. Recurrence of varus was observed in limbs with a residual abnormal medial mechanical axis deviation due to femoral deformity. A hundred percent incidence of equinus was observed in limbs with tibial lengthening of more than 40%, with distal tibial lengthening of more than 15%. To minimize the risk for occurrence of equinus, we recommend restriction of distal tibial lengthening in achondroplasia to less than 15%, although total tibial lengthening may exceed 40%. Fibula malalignment was not observed after double fibula osteotomy. This procedure is safe and efficacious if performed with strict adherence to prescribed technique.