Progressive Spinal Deformity Research Articles

Association of Circulating YKL-40 Levels and CHI3L1 Variants with the Risk of Spinal Deformity Progression in Adolescent Idiopathic Scoliosis

The cellular and molecular mechanisms underlying spinal deformity progression in adolescent idiopathic scoliosis (AIS) remain poorly understood. In this study, 804 French-Canadian patients and 278 age- and sex-matched controls were enrolled and genotyped for 12 single nucleotide polymorphisms (SNPs) in the chitinase 3-like 1 (CHI3L1) gene or its promoter. The plasma YKL-40 levels were determined by ELISA. We showed that elevation of circulating YKL-40 levels was correlated with a reduction of spinal deformity progression risk. We further identified significant associations of multiple CHI3L1 SNPs and their haplotypes with plasma YKL-40 levels and scoliosis severity as a function of their classification in a specific endophenotype. In the endophenotype FG3 group, we found that patients harboring the haplotype G-G-A-G-G-A (rs880633|rs1538372|rs4950881|rs10399805|rs6691378|rs946261), which presented in 48% of the cases, showed a positive correlation with the plasma YKL-40 levels (P = 7.6 × 10−6 and coefficient = 36). Conversely, the haplotype A-A-G-G-G-G, which presented in 15% of the analyzed subjects, showed a strong negative association with the plasma YKL-40 levels (P = 2 × 10−9 and coefficient = −9.56). We found that this haplotype showed the strongest association with AIS patients in endophenotype FG2 (P = 9.9 × 10−6 and coefficient = −13.53), who more often develop severe scoliosis compared to those classified in the other two endophenotypes. Of note, it showed stronger association in females (P = 1.6 × 10−7 and coefficient = −10.08) than males (P = 0.0021 and coefficient = −9.01). At the functional level, we showed that YKL-40 treatments rescued Gi-coupled receptor signalling dysfunction occurring in primary AIS osteoblasts. Collectively, our findings reveal a novel role for YKL-40 in AIS pathogenesis and a new molecular mechanism interfering with spinal deformity progression.

Risk factor analysis of progressive spinal deformity after resection of intramedullary spinal cord tumors in patients who underwent laminoplasty: a report of 105 consecutive cases.

Laminoplasty has been used in recent years as an alternative approach to laminectomy for preventing spinal deformity after resection of intramedullary spinal cord tumors (IMSCTs). However, controversies exist with regard to its real role in maintaining postoperative spinal alignment. The purpose of this study was to examine the incidence of progressive spinal deformity in patients who underwent laminoplasty for resection of IMSCT and identify risk factors for progressive spinal deformity. Data from IMSCT patients who had undergone laminoplasty at Beijing Tsinghua Changgung Hospital between January 2014 and December 2016 were retrospectively reviewed. Univariate tests and multivariate logistic regression analysis were used to assess the statistical relationship between postoperative spinal deformity and radiographic, clinical, and surgical variables. One hundred five patients (mean age 37.0 ± 14.5 years) met the criteria for inclusion in the study. Gross-total resection (> 95%) was obtained in 79 cases (75.2%). Twenty-seven (25.7%) of the 105 patients were found to have spinal deformity preoperatively, and 10 (9.5%) new cases of postoperative progressive deformity were detected. The mean duration of follow-up was 27.6 months (SD 14.5 months, median 26.3 months, range 6.2-40.7 months). At last follow-up, the median functional scores of the patients who did develop progressive spinal deformity were worse than those of the patients who did not (modified McCormick Scale: 3 vs 2, and p = 0.04). In the univariate analysis, age (p = 0.01), preoperative spinal deformity (p < 0.01), extent of tumor involvement (p < 0.01), extent of abnormal tumor signal (p = 0.02), and extent of laminoplasty (p < 0.01) were identified as factors associated with postoperative progressive spinal deformity. However, in subsequent multivariate logistic regression analysis, only age ≤ 25 years and preoperative spinal deformity emerged as independent risk factors (p < 0.05), increasing the odds of postoperative progressive deformity by 4.1- and 12.4-fold, respectively (p < 0.05). Progressive spinal deformity was identified in 25.7% patients who had undergone laminoplasty for IMSCT resection and was related to decreased functional status. Younger age (≤ 25 years) and preoperative spinal deformity increased the risk of postoperative progressive spinal deformity. The risk of postoperative deformity warrants serious reconsideration of providing concurrent fusion during IMSCT resection or close follow-up after laminoplasty.

Study of progression of spinal deformity in dorsolumbar spinal injuries managed by internal fixation

Study of progression of spinal deformity in dorsolumbar spinal injuries managed by internal fixation

EVALUATION OF THE VEPTR SYSTEM IN THE MANAGEMENT OF SPINAL DEFORMITIES BETWEEN 2008 AND 2014 AT THE ROOSEVELT INSTITUTE

ABSTRACT Objective: Traditional surgical treatments, such as on-site fusion and hemiepiphysiodesis, have not addressed chest deformity in its three dimensions, and are usually insufficient and unpredictable for the management of congenital and neuromuscular scoliosis. The application of the Vertical Expandable Prosthetic Titanium Rib (VEPTR) is a technique developed to treat early-onset progressive scoliosis that elongates the spine and thoracic wall, allowing adequate lung development. Methods: A case series retrospective study was conducted. We included 23 patients, including fifteen females and eight males diagnosed with congenital and neuromuscular scoliosis, who were treated with VEPTR type implants between January 2008 and May 2014. We obtained data about the implant and pre and postoperative radiographic images to assess the magnitude of the curve, and we measured the Cobb angle and length after lengthening, as well as evaluating the complications found. Results: There was an improvement in the postoperative Cobb angle. In patients with congenital scoliosis, deformity correction was 8.6% (p=0.014), and in neuromuscular scoliosis, we observed deformity correction of 19.5% (p=0.009). Likewise, we found gains in thoracic height through the device, which results in an average 10% lengthening of the spine in congenital scoliosis. In this study, we identified complications such as material migrations, rib synostosis, pressure zones, rib fracture, hemothorax, and deep wound infection. Conclusion: The natural history of progressive spinal deformity was improved in most of the minors, through the use of VEPTR. This allows us to continue managing patients in the future, in order to make a deeper assessment of its performance in treatment of early onset scoliosis. Level of Evidence III; Therapeutic studies - Investigating the results of a treatment.

Partial Vertebrectomies without Instrumented Stabilization During En Bloc Resection of Primary Bronchogenic Carcinomas Invading the Spine: Feasibility Study and Results on Spine Balance

It is unknown whether spinal instrumentation is required to prevent deformity after partial vertebrectomy in the treatment of primary bronchogenic carcinomas invading the spine (PBCIS). In this study, we focus on the postoperative spine deformity in patients who underwent operation for partial vertebrectomies without instrumentation during en bloc PBCIS resection. Our objective was to determine whether deformity depends on the type of vertebral resection and if any vertebral resection threshold can be observed to justify additional spinal instrumentation. This is a retrospective study, including all patients with PBCIS operated without spinal instrumentation from 2009 to 2018. Partial vertebrectomies were classified into categories A, B, and C depending on vertebral resection. Patients had long-term radiologic follow-up to assess the spine deformity evolution. Eighteen patients were included. The median follow-up was 27 months. Four patients underwent a secondary posterior instrumentation surgical procedure due to progressive spinal deformity. A low-risk group of deformation was characterized as type A resection and type B resection on less than 3 vertebrae. There are no validated criteria to justify a systematic spinal instrumentation when performing a partial vertebrectomy during en bloc resection of PBCIS. Performed alone without spine instrumentation, both type A and type B resections on less than 3 resected vertebrae were not subject to sagittal and coronal deformity even after a long follow-up, emphasizing that a systematic stabilization is not needed in this low-risk group. These results could help to reduce the perioperative morbidity of these procedures that are usually long and complex.

Metastatic Spinal Cord Compression: Unraveling the Diagnostic and Therapeutic Challenges.

Malignant spinal cord compression (MSCC) is one of the most devastating complications of cancer. Patients often present with a history of progressive pain, paralysis, sensory loss, progressive spinal deformity, and loss of sphincter control. It is an emergency that requires rapid decision making on the part of several specialists, given the risk of permanent spinal cord injury or death. The goals of treatment in spinal metastases are pain control and improvement of neurological function in order to achieve better quality of life (QoL). The standard of care in most cases is rapid initiation of corticosteroids in combination with either surgical decompression in case of an operable candidate, followed by radiation therapy (RT) or RT alone. Surgery is associated with improved outcomes, but is not appropriate for many patients presenting with advanced symptoms of MSCC, such as paralysis, or those with a poor performance status, or cachexic state, as well as altered mental conditions, co-morbidities, surgical risks, and limited life expectancy. On the other hand, aggressive surgical treatment and post-operative RT is advocated for those with more favorable prognosis, or who are expected to have higher neurological recovery potential. Many candidates may require for combined anterior and posterior approaches to effectively deal with the compressive pathology and stabilize the spine. Most patients are presently treated by primary RT, given with the aim of improving function and symptom management. However, there is still debate regarding the most appropriate RT schedule. Rehabilitation can serve to relieve symptoms, QoL, enhance functional independence, and prevent further complications. Ambulatory status has been found to be an important prognostic factor for patients with MSCC.

Nighttime bracing with the Providence thoracolumbosacral orthosis for treatment of adolescent idiopathic scoliosis: A retrospective consecutive clinical series.

Orthotic treatment for adolescent idiopathic scoliosis is a mainstay in nonoperative treatment to prevent progressive spinal deformity. To determine the effectiveness of the Providence orthosis in the treatment of adolescent idiopathic scoliosis. Retrospective review. Patients treated with a Providence orthosis for adolescent idiopathic scoliosis were reviewed. Inclusion criteria included the following: age of 10-18 years; curve magnitude of 25°-40°; Risser stage of 0-2; and, if female, <1 year post menarche at the time of brace initiation. Failure was defined as curve magnitudes progressing >5° or to >45° or surgery. Radiographs and clinical information were recorded and compared between treatment success and failure cohorts. 56 patients (51 female and 5 male; average of 12.26 years) were identified with average of 2.21-year follow-up and a 57.1% success rate for preventing curve progression. Factors associated with successful treatment included curve apex T10 and caudal and Risser sign ⩾ 1. Multivariate analysis identified Risser ⩾ 1 and curve apex T10 and caudal as independent predictors of successful treatment. The Providence nighttime orthosis can be an effective treatment for adolescent idiopathic scoliosis. Curve Apex at T10 or caudal was an independent predictors of treatment success. This study identifies variables associated with treatment success using the Providence nighttime orthosis in a consecutive series of adolescent idiopathic scoliosis patients. This information provides the foundation for identifying ideal patients for nighttime bracing to guide clinical treatment.

Clinical application and cases examples of a new treatment algorithm for treating thoracic and lumbar spine trauma.

Review of illustrative cases of a new algorithm to help in the treatment decision of thoracolumbar spine trauma. To illustrate the use of the new algorithm for managing thoracic and lumbar spine trauma. Recently, a new algorithm for helping in the decision of the best treatment modality for thoracolumbar spine trauma (TLST) was published. The algorithm considers injury morphology, neurological status, clinical status (pain and disability), and also multimodal radiological evaluation (MMRE) in the decision for non-operative versus operative treatment for TLST. Injuries were classified in three groups: (1) stable injuries, (2) potentially unstable injuries/ delayed instability, or (3) clearly unstable injuries. Cases examples of the algorithm application were presented and discussed. Stable injuries (minor fractures without instability) are non-surgically treated; potentially unstable injuries or associated with delayed instability may be initially managed non-surgically and operative treatment is an option, especially in the setting of important pain, deformity or a new neurological deficit. Clearly unstable injuries are treated surgically as soon as possible to avoid neurological worsening, severe pain, and/ or progressive spinal deformity. Clinical examples of TLST were presented, discussed and classified as stable, potentially unstable and clearly unstable injuries. Further studies addressing the reliability and safety of this algorithm are necessary.

Posterior Excision of Hemivertebrae; The Presence of a Hemilamina may be Misleading

Congenital scoliosis is a lateral curvature of the spine that results from the differing growth potential of vertebral anomalies present at birth. It can lead to severe progressive spinal deformity. The different types of vertebral body anomaly that are associated with congenital scoliosis have been classified based on the appearance of plain radiographs [1-3]. No treatable cause for the vertebral anomalies that result in congenital scoliosis has been identified. Predictions can be made about the severity of the resultant spinal deformity based on classification of the anomalies present, and a knowledge of their natural history [1,4]. Decisions regarding surgical treatment are based on knowledge of the natural history and likely resultant deformity.

What's New in Congenital Scoliosis?

Congenital scoliosis is a failure of vertebral formation, segmentation, or a combination of the 2 arising from abnormal vertebral development during weeks 4 to 6 of gestation. The associated spinal deformity can be of varying severity and result in a stable or progressive deformity based on the type and location of the anomalous vertebra(e). Bracing for congenital scoliosis is rarely indicated, while recent reports have demonstrated the utility of serial derotational casting for longer curves with multiple anomalous vertebrae as an effective "time buying strategy" to delay the need for surgery. Earlier hemivertebra excision and short-segment posterior spinal fusion have been advocated to prevent future curve progression of the deformity and/or the development of large compensatory curves. It has been shown in recent long-term follow-up studies that growth rates of the vertebral body and spinal canal are not as dramatically affected by pedicle screw instrumentation at a young age as once thought. Growth friendly surgery with either spine-based or rib-based anchors has demonstrated good results with curve correction while maintaining spinal growth. Rib-based anchors are typically more commonly indicated in the setting of chest wall abnormalities and/or when spinal anatomy precludes placement of spinal instrumentation. Recently, magnetically controlled growing rods have shown promising results in several studies that include a small subset of congenital scoliosis cases. A literature search was performed to identify existing studies related to the treatment of congenital scoliosis published from January 1, 2005 to June 1, 2016. Databases included PubMed, Medline, and the Cochrane Library. The search was limited to English articles and yielded 36 papers. This project was initiated by the Pediatric Orthopaedic Society of North America Publications Committee and was reviewed and approved by the Pediatric Orthopaedic Society of North America Presidential Line. A total of 36 papers were selected for review based upon new findings. Classic manuscripts on congenital scoliosis are also included to provide sufficient background information. Congenital scoliosis represents a wide range of pathology from the simple, stable hemivertebra to the complex, progressive spinal deformity with chest wall abnormalities and associated cardiac, renal, and neural axis anomalies. This paper reviews the natural history and associated anomalies with congenital scoliosis as well as the most up-to-date classification schemes and various treatment options for the care of this challenging patient population. Level 5.

The natural history of spinal deformity in patients with Coffin-Lowry syndrome

PurposeLittle is known about the natural history of spinal deformities in Coffin-Lowry syndrome (CLS). Our goal was to evaluate the spinal deformity progression and clinical impact.MethodsIn this institutional review board-approved study, we performed a multinational retrospective review of six male CLS patients, aged 13 to 22 years at final follow-up, for a mean of 7.25 years (3 to 13).ResultsAll showed delayed skeletal maturity. Three had calcifications of their lower cervical ligamentum flavum, all experienced neural axis abnormalities, including lower extremity weakness, numbness and tingling and in one, quadriparesis. Only two were ambulatory at final follow-up.All had significant spinal abnormalities, including severe progressive thoracic lordosis, thoracolumbar kyphosis and scoliosis. All had undergone spinal fusion or were being evaluated for surgery.ConclusionCLS is a rare X-linked mutation in the RSK2 gene, affecting between 1/50 000 to 100 000 people. There are two reports in the literature of patients with calcifications of their ligamentum flavum. Both had neural axis abnormalities and one had acute onset quadriplegia. Analysis of their ligamentum flavum found abundant central calcifications. Despite our small cohort we found 50% had calcifications and 100% had neurologic consequences associated with those calcifications. There was a 100% rate of deformity progression.They all exhibited delay in skeletal maturity, which mandates longer follow-up and has implications for surgical planning.From our cohort and literature review, the natural history of CLS supports frequent patient evaluation and a lower threshold for correction of spinal deformities. Aiming to avoid spinal cord compression and improve or avoid neurological deterioration.Level of EvidenceIV - retrospective study

SURGICAL CORRECTION OF SPINAL DEFORMITIES IN PATIENTS WITH EHLERS-DANLOS SYNDROME

Objective. To analyze surgical treatment results in patients with severe progressive spinal deformities owing to Ehlers-Danlos syndrome. Material and Methods. A total of nine patients with spinal deformities owing to Ehlers-Danlos syndrome were operated on during the period of 2003-2013. Mean age of patients was 12.5 years. One patient undergoes multistage treatment with VEPTR instrumentation, and eight patients underwent corrective posterior surgery using third-generation segmental instrumentation. Posterior correction was preceded by anterior stage including discectomy and interbody fusion with bone autograft in six cases. Results. The mean primary curve was 95.2° before surgery, 50.9° immediately after surgery, and 59.1° at final follow-up. The kyphotic component was 93.7°, 53.9°, and 59.6°, respectively. The coronal trunk imbalance was 28.3 mm before surgery, 39.4 mm immediately after surgery, and 22.0 mm at final follow-up. Complications were observed in three patients: right-sided pneumothorax in one case, and instability of the cranial anchor of instrumentation system, which required reoperation in two cases. There were neither pyogenic or neurologic complications, nor massive bleeding. Conclusion. Spinal deformities caused by Ehlers-Danlos syndrome are rare, though rapidly progressive disorders, which attain significant magnitude. Timely surgical treatment allows achieving satisfactory correction of both scoliosis and kyphosis, though can cause vascular and neuriological complications, especially with the anterior approach.

The scope of minimally invasive techniques in spinal infections

The primary goals for treating infectious spinal conditions are to make an accurate diagnosis, isolate the causative organism, and prescribe effective antibiotic therapy based on the culture reports. A positive culture is extremely important for successful treatment and prevention of further morbidity. Surgically collected samples have shown to have a greater chance of demonstrating growth of organism on culture as compared to computed tomography-guided fine-needle samples. Surgical drainage and/or reconstruction with/or without fixation is usually indicated when there is no or poor response to antibiotic therapy, systemic toxicity with evidence of large collections, progressive spinal deformity, or instability or neurological impairment. However, the incidence of perioperative morbidity is particularly increased in elderly patients or in those with a poor general condition. With improved instrumentation and techniques in minimally invasive spine surgery, spinal infections can be successfully treated by minimally invasive debridement followed by pharmacological treatment, without causing any destabilization to spine. Where major reconstruction and fixation procedures are deemed mandatory, various MIS techniques can be utilized to decrease the surgery related morbidity and allow for faster rehabilitation. These procedures are associated with steep learning curve. With the advent of intraoperative navigation, the exposure to radiations can be significantly reduced.

Deep postoperative spine infection treated by negative pressure therapy in patients with progressive spinal deformities.

The aim of the study is to review the outcome of using the VAC system in children and adolescents who have developed postoperative spinal infection after posterior instrumented spinal fusion, and to evaluate whether this technique is also feasible in patients treated with posterior instrumented fusion with polyester sublaminar bands. A total of 11 out of 118 consecutive children and adolescents (5 males) with deep postoperative spinal infection were identified; infections were categorised as early (acute), delayed (subacute) or late (chronic) according to time of onset. Irrespective of the etiology and the onset, all the deep infections were managed with the reported technique. All the patients had regular clinical and radiological follow-up. Eight out of 11 patients developed an early (72.7%), 2 a delayed (18.2%) and 1 a late deep postoperative infection (9.1%); 7 out of 11 (63.6%) showed severe mental compromise. No statistically significant differences were observed for mean number of VAC dressing changes (p = 0.81) and mean length of hospitalisation comparing patients with early infection versus patients with delayed or late infections (p = 0.32). Mean number of VAC dressing changes (p = 0.02) and mean number of hospitalisation days (p = 0.05) were higher in patients with underlying neurological disorders than in those without, while mean length of hospitalisation was longer in neuromuscular patients. The application of the VAC system, as an adjunct to surgical debridement and adequate antibiotic therapy, is a reliable method for the treatment of postoperative infection in children and adolescents undergoing spinal instrumentation and fusion. It can reduce the need for further complex soft-tissue procedure, removal of hardware with consequent loss of correction, and pseudoarthrosis. Finally, the use of VAC therapy is not contraindicated in patients treated with hybrid constructs with sublaminar bands. III.

Radiographic and Respiratory Effects of Growing Rods in Children With Spinal Muscular Atrophy.

Respiratory weakness and spinal deformity are common in patients with spinal muscular atrophy (SMA). Posterior (distraction type) growing rods have recently gained favor as a treatment option in this population, due to their ability to prevent spinal deformity progression and their potential to allow lung volumes to increase over time. The objective of this study was to determine the impact of posterior growing rods on the spinal alignment and respiratory function in children with SMA with intermediate term follow-up. A single center, retrospective review was performed on SMA patients treated with growing rods, inserted between 2004 and 2010, with a minimum of 2-year follow-up. SMA type, changes in the route of bi-level positive airway pressure respiratory support and the amount of time receiving respiratory support are reported. Pulmonary function tests (PFTs) and radiographs were reviewed and data evaluated preinsertion, postinsertion, and at latest follow-up. Sixteen children with SMA (5 type I, 11 type II) met inclusion criteria. The average age of insertion was 5.8 (±1.5) years, the median number of lengthenings was 4 (range, 3 to 5), and the median time between insertion and last clinical review was 4.7 (range, 2.7 to 9.5) years. Radiographic review demonstrated significant (P<0.05) improvements in the following: Spinal curve magnitude, pelvic obliquity, space available for the lung, rib vertebral angle difference, and thoracic kyphosis following growing rod implantation. Thoracic and lumbar height and chest width and depth increased significantly (P<0.05) over the lengthening process. None of the patients initially required more than noninvasive positive pressure ventilation support. Fifteen of the 16 experienced no changes in their noninvasive positive pressure ventilation support needs throughout the study duration, requiring support only at night and naps. Serial PFTs were available for 6 children with SMA type II. PFTs demonstrated significant improvements in absolute forced vital capacity (FVC), minimal changes in the maximal inspiratory and expiratory pressures, and a gradual worsening of percent predicted FVC. Clinical respiratory support requirements appear to stabilize following the insertion and lengthening of posterior based growing rods in the SMA population. Similar to previous studies, increased spinal height and thoracic cavity size were noted throughout the process. Despite an increasing absolute FVC, the percent predicted FVC diminished over time. Level IV-therapeutic.

Effects of bone damage on creep behaviours of human vertebral trabeculae

A subgroup of patients suffering with vertebral fractures can develop progressive spinal deformities over time. The mechanism underlying such clinical observation, however, remains unknown. Previous studies suggested that creep deformation of the vertebral trabeculae may play a role. Using the acoustic emission (AE) technique, this study investigated effects of bone damage (modulus reduction) on creep behaviours of vertebral trabecular bone. Thirty-seven human vertebral trabeculae samples were randomly assigned into five groups (A to E). Bones underwent mechanical tests using similar experimental protocols but varied degree of bone damage was induced. Samples first underwent creep test (static compressive stress of 0.4MPa) for 30min, and then were loaded in compression to a specified strain level (0.4%, 1.0%, 1.5%, 2.5%, and 4% for group A to E, respectively) to induce different degrees of bone damage (0.4%, no damage control; 1.0%, yield strain; 1.5%, beyond yield strain, 2.5% and 4%, post-ultimate strains). Samples were creep loaded (0.4MPa) again for 30min. AE techniques were used to monitor bone damage. Bone damage increased significantly from group A to E (P<0.05), with >30% of modulus reduction in group D and E. Before compressive loading, creep deformation was not different among the five groups and AE hits in creep test were rare. After compressive loading, creep deformation was significantly greater in group D and E than those in other groups (P<0.05). The number of AE hits and other AE measurements during creep test were significantly greater in group D and E than in group A, B, and C (P<0.05 for all). Data suggested that with the increase of vertebral trabecular bone damage, substantial creep deformation may occur even when the vertebra was under physiological loads. The boosted creep deformation observed may be attributed to newly created trabecular microfractures. Findings provide a possible explanation as to why some vertebral fracture patients develop progressive spinal deformity over time.

Spondylodiscitis revisited.

Spondylodiscitis may involve the vertebral bodies, intervertebral discs, paravertebral structures and spinal canal, with potentially high morbidity and mortality rates.A rise in the susceptible population and improved diagnosis have increased the reported incidence of the disease in recent years.Blood cultures, appropriate imaging and biopsy are essential for diagnosis and treatment.Most patients are successfully treated by conservative means; however, some patients may require surgical treatment.Surgical indications include doubtful diagnosis, progressive neurological deficits, progressive spinal deformity, failure to respond to treatment, and unresolved pain.Cite this article: EFORT Open Rev 2017;2:447–461. DOI: 10.1302/2058-5241.2.160062

Osteoporosis and the Management of Spinal Degenerative Disease (II).

Osteoporosis has become a major medical problem as the aged population of the world rapidly grows. Osteoporosis predisposes patients to fracture, progressive spinal deformities, and stenosis, and is subject to be a major concern before performing spine surgery, especially with bone fusions and instrumentation. Osteoporosis has often been considered a contraindication for spinal surgery, while in some instances patients have undergone limited and inadequate procedures in order to avoid concomitant instrumentation. As the population ages and the expectations of older patients increase, the demand for surgical treatment in older patients with osteoporosis and spinal degenerative diseases becomes progressively more important. Nowadays, advances in surgical and anesthetic technology make it possible to operate successfully on elderly patients who no longer accept disabling physical conditions. This article discusses the biomechanics of the osteoporotic spine, the diagnosis and management of osteoporotic patients with spinal conditions, as well as the novel treatments, recommendations, surgical indications, strategies and instrumentation in patients with osteoporosis who need spine operations.

P116 - Safety and Efficacy of Osteotomy for Congenital Spinal Deformity Associated with Split Spinal Cord Malformation

PURPOSE: The aim of this study is to retrospectively evaluate the safety and efficacy of osteotomy for 56 consecutive patients, who had progressive congenital spinal deformity (CSD) associated with split spinal cord malformation (SSCM).

Risk factors for progressive neuromuscular scoliosis requiring posterior spinal fusion after selective dorsal rhizotomy.

OBJECTIVE Selective dorsal rhizotomy (SDR) via limited laminectomy is an effective treatment of lower-extremity spasticity in the pediatric population. Children with spasticity are also at risk for neuromuscular scoliosis; however, specific risk factors for progressive spinal deformity requiring posterior spinal fusion (PSF) after SDR are unknown. The authors' goal was to identify potential risk factors. METHODS The authors performed a retrospective cohort study of patients who underwent SDR via limited laminectomy between 2003 and 2014 and who had at least 1 year of follow-up. They analyzed demographic, clinical, and radiographic variables to elucidate risk factors for progressive neuromuscular scoliosis. The primary outcome was need for PSF. RESULTS One hundred thirty-four patients underwent SDR and had at least 12 months of follow-up (mean 65 months); 48 patients (36%) had detailed pre- and postoperative radiographic data available. The mean age at surgery was 10 years (SD 5.1 years). Eighty-four patients (63%) were ambulatory before SDR, 109 (82%) underwent a single-level laminectomy, and a mean of 53% of the dorsal rootlets from L-1 to S-1 were sectioned. Fifteen patients (11.2%) subsequently required PSF for progressive deformity. Nonambulatory status (p < 0.001) and a preoperative Cobb angle > 30° (p = 0.003) were significantly associated with PSF on univariate analysis, but no statistically significant correlation was found with any clinical or radiographic variable and PSF after SDR on multivariate regression analysis. CONCLUSIONS Patients with preoperative nonambulatory status and Cobb angle > 30° may be at risk for progressive spinal deformity requiring PSF after SDR. These are well-known risk factors for progressive deformity in children with spasticity in general. Although our analysis suggests SDR via limited laminectomy may not significantly accelerate the development of neuromuscular scoliosis, further case-control studies are critical to elucidate the impact of SDR on spinal deformity.