Analysis of Single Nucleotide Polymorphism in Adolescent Idiopathic Scoliosis in Korea: For Personalized Treatment

PURPOSE: The incidence of adolescent idiopathic scoliosis (AIS) has rapidly increased, and with it, physician consultations and expenditures (about one and a half times) in the last 5 years. Recent etiological studies reveal that AIS is a complex genetic disorder that results from the interaction of multiple gene loci and the environment. For personalized treatment of AIS, a tool that can accurately measure the progression of Cobb's angle would be of great use. Gene analysis utilizing single nucleotide polymorphism (SNP) has been developed as a diagnostic tool for use in Caucasians but not Koreans. Therefore, we attempted to reveal AIS-related genes and their relevance in Koreans, exploring the potential use of gene analysis as a diagnostic tool for personalized treatment of AIS therein. MATERIALS AND METHODS: A total of 68 Korean AIS and 35 age- and sex-matched, healthy adolescents were enrolled in this study and were examined for 10 candidate scoliosis gene SNPs. RESULTS: This study revealed that the SNPs of rs2449539 in lysosomal-associated transmembrane protein 4 beta (LAPTM4B) and rs5742612 in upstream and insulin-like growth factor 1 (IGF1) were associated with both susceptibility to and curve severity in AIS. The results suggested that both LAPTM4B and IGF1 genes were important in AIS predisposition and progression. CONCLUSION: Thus, on the basis of this study, if more SNPs or candidate genes are studied in a larger population in Korea, personalized treatment of Korean AIS patients might become a possibility.

Results of Dual Growing Rods Treatment for Progressive Pediatric Spinal Deformity

STUDY DESIGN: A prospective study. OBJECTIVES: To report the results of new designed dual growing rods system for progressive pediatric spinal deformity. SUMMARY OF LITERATURE REVIEW: The current expandable spinal implant system appears effective in controlling progressive pediatric spinal deformity, allowing for spinal growth. However, there was no report concerning the growing rod in Korea. MATERIALS AND METHODS: Between 2010 and 2011, seven pediatric patients, who had a minimum of 1year follow-up, had undergone surgery for spinal deformity correction with a dual growing rods technique. We analyzed the demographic and radiologic data, including height, weight, age at surgery, diagnosis, number of lengthening, Cobb's angle of the major curve, thoracic kyphosis angle, lumbar lordosis angle, T1-S1 length, instrumented segment length, and complications, from the preoperative period to the last follow up period. RESULTS: Four male and three female patients with 5 neuromuscular scoliosis, 1 idiopathic juvenile osteoporosis and 1 spondyloepiphyseal dysplasia had underwent corrective surgery with dual growing rods. The mean age at the initial surgery was 11.6 years (7-13.8). The mean follow-up duration was 19.3 months (12-24), and the mean lengthening procedure time was 2.8 (2-4) for every patient. Cobb's angle of scoliosis curve was corrected from preoperative 80.2degrees(55-136) to 37.6degrees (15-81) on the last follow-up. Thoracic kyphosis angle and lumbar lordosis angle were changed from preoperative 48.7degrees(12-101) and 38.3degrees(9-72) to 44.5degrees(12-75) and 18.8degrees(1-46) on the last follow-up, respectively. Growth length during the follow-up period was measured as instrumented segment is 46 mm (33-59) and T1-S1 segment is 82 mm (66-98). Complications, such as breakage of rod in 3 cases and soft tissue infection in 1 case, occurred during the follow-up period. CONCLUSIONS: New designed dual growing rods system for pediatric patients with progressive spinal deformity is an effective and relatively safe method because of adequate correction and acceptable rate of complications.

Video-Assisted Thoracoscopic Surgery Plus Lumbar Mini-Open Surgery for Adolescent Idiopathic Scoliosis

PURPOSE: The objectives of this study are to describe the outcome of adolescent idiopathic scoliosis (AIS) patients treated with Video Assisted Thoracoscopic Surgery (VATS) plus supplementary minimal incision in the lumbar region for thoracic and lumbar deformity correction and fusion. MATERIALS AND METHODS: This is a case series of 13 patients treated with VATS plus lumbar mini-open surgery for AIS. A total of 13 patients requiring fusions of both the thoracic and lumbar regions were included in this study: 5 of these patients were classified as Lenke type 1A and 8 as Lenke type 5C. Fusion was performed using VATS up to T12 or L1 vertebral level. Lower levels were accessed via a small mini-incision in the lumbar area to gain access to the lumbar spine via the retroperitoneal space. All patients had a minimum follow-up of 1 year. RESULTS: The average number of fused vertebrae was 7.1 levels. A significant correction in the Cobb angle was obtained at the final follow-up (p = 0.001). The instrumented segmental angle in the sagittal plane was relatively well-maintained following surgery, albeit with a slight increase. Scoliosis Research Society-22 (SRS-22) scores were noted have significantly improved at the final follow-up (p < 0.05). CONCLUSION: Indications for the use of VATS may be extended from patients with localized thoracic scoliosis to those with thoracolumbar scoliosis. By utilizing a supplementary minimal incision in the lumbar region, a satisfactory deformity correction may be accomplished with minimal post-operative scarring.

Epidemiology of the Spinal Cord and Cauda Equina Injury in Korea: Multicenter Study

STUDY DESIGN: Multi-center study, questionnaire survey. OBJECTIVES: To offer a database of spinal cord injury (SCI) by reviewing statistics and literatures of other countries, investigating the overall mechanism, injury patterns and treatment of SCI. SUMMARY OF LITERATURE REVIEW: There are no preexisting domestic studies (collectively conducted by multi-centers) of the prevalence and treatment of SCI. MATERIALS AND METHODS: From September 2006 to August 2009, 47 cases of SCI in 6 universities were investigated retrospectively. 17 questionnaire contents including the courses of injury-to-treatment were studied with data gathered from surveys. RESULTS: The average age of patients was 48.4-years-old, male to female ratio was 33 to 14. The cases of falling from a height were 22 cases (47%), lumbar area 19 cases (40%), and unstable bursting fracture 24 cases (51%) the most. Complete and incomplete paralyses were 19 cases (40%) and 28 cases (60%), respectively. High dose steroids were injected in 16 cases (NASCIS II) and 9 cases (NASCIS III). 14 cases presented complications and operations were performed 46 cases (98%). 12 cases (26%) arrived at the hospital within 4 hours of injury, 11 cases (23%) in 8 hours. On the way to the hospital, proper emergency treatment was performed in 25 cases (53%), and 30 cases (64%) had a clear understanding of SCI after the final diagnosis. CONCLUSIONS: This is the first study that offers a comprehensive database of spinal cord injury (SCI), by investigating the overall mechanism, injury patterns, and treatment of SCI; this study is expected to be used in the future as an important reference material for spinal cord injury statistics and a standard for care.

A Spinal Cord Astrocytoma and Its Concurrent Osteoblastic Metastases at the Time of the Initial Diagnosis: a Case Report and Literature Review

Bone metastasis from a spinal cord astrocytoma has been reported only twice in the English medical literature. It is generally known that bone metastasis is found after the initial diagnosis with/without intervening surgery rather than being found at the time of the diagnosis of astrocytoma. The purpose of this article is to report for the first time a case of concurrent bone metastasis from a spinal cord astrocytoma at the time of diagnosing the spinal cord astrocytoma.

Symmetrical Peripheral Gangrene after Pulmonary Hemorrhage / 대한정형외과학회잡지

Symmetrical peripheral gangrene (SPG) is characterized by distal ischemic damage in two or more extremities without a large vessel obstruction. This syndrome is associated with low cardiac output, sepsis, malignancy, disseminated intravascular coagulation (DIC) and the administration of vasoactive drugs. We report a case of SPG in a patient with pulmonary hemorrhage, sepsis and DIC who had been administered dopamine.

Comparison of Mechanical Property of Conventional Rods versus Growing Rods for Pediatric Early Onset Scoliosis

STUDY DESIGN: This is a mechanical study. OBJECTIVES: We wanted to investigate the mechanical properties of newly developed dual growing rods for obtaining approval for their clinical application. SUMMARY OF LITERATURE REVIEW: The current expandable spinal implant system appears effective for controlling progressive early onset scoliosis, and it allows for spinal growth and improving lung development. MATERIALS AND METHODS: We investigate the yield load and ultimate load during compression, tension and torsion of the growing rods and the conventional rods assembly using UHMWPE blocks, and the diameter of the rods was 6.0 mm and they expanded 5cm long. We also performed a fatigue test with growing rods, and the diameter of which was 6.0 mm and it expanded 2.5cm long. The guideline for the American Society for Testing Materials was followed during the entire mechanical test. With the growing rods and conventional rods, we tested for each mechanical property7 times with the new rods and blocks. RESULTS: The yield load of the growing rods and conventional rods were 845.2+/-18.2 (N) and 812.9+/-29.9 (N), respectively, and the ultimate load of the growing rods and conventional rods were 961.9+/-31.1 (N) and 914.9+/-25.6 (N), respectively, when compression force was applied. The yield load and ultimate load of the growing rods were statistically higher than those of the conventional rods (p0.05). The yield loads of the growing rods and conventional rods were 11.56+/-0.59 (Nm) and 12.46+/-0.71 (Nm), respectively, the ultimate loads of the growing rods and conventional rods were 16.97+/-0.94 (Nm) and 17.42+/-2.66 (Nm) during the torsion, respectively. The yield load and ultimate load of the growing rods were statistically lower than that of the conventional rods (p<0.05). CONCLUSIONS: The newly developed growing rods have a higher yield load and ultimate load under compression, a similar ultimate load under tension and a lower yield load and ultimate load under torsion. The differences of the yield load and ultimate load under torsion were minimal, and so the growing rods and conventional rods have similar mechanical properties.

Video-Assisted Thoracoscopic Surgery for Correction of Adolescent Idiopatic Scoliosis: Comparison of 4.5 mm versus 5.5 mm Rod Constructs

PURPOSE: The purpose of this study is to report the comparative results of thoracoscopic correction achieved via cantilever technique using a 4.5 mm thin rod and the poly-axial reduction screw technique using a 5.5 mm thick rod in Lenke type 1 adolescent idiopathic scoliosis (AIS). MATERIALS AND METHODS: Radiographic data, Scoliosis Research Society (SRS) patient-based outcome questionnaires, and operative records were reviewed for forty-nine patients undergoing surgical treatment of scoliosis. The study group was divided into a 4.5 mm thin rod group (n = 24) and a 5.5 mm thick rod group (n = 25). The radiographic parameters that were analyzed included coronal curve correction, the most caudal instrumented vertebra tilt angle correction, coronal balance, and thoracic kyphosis. RESULTS: The major curve was corrected from 49.8degrees and 47.2degrees pre-operatively to 24.5degrees and 18.8degrees at the final follow-up for the thin and thick rod groups, respectively (50.8% vs. 60.2% correction). There were no significant differences between the two groups in terms of kyphosis, coronal balance, or tilt angle at the time of the final follow-up. The mean number of levels fused was 6.2 in the thin rod group, compared with 5.9 levels in the thick rod group. There were no major intraoperative complications in either group. CONCLUSION: Significant correction loss was observed in the thin rod system at the final follow-up though both groups had comparable correction immediately post-operative. Therefore, the thick rod with poly axial screw system helps to maintain post-operative correction.

Antibiotic Microbial Prophylaxis for Spinal Surgery: Comparison between 48 and 72-Hour AMP Protocols

STUDY DESIGN: This is a prospective randomized cohort study. PURPOSE: We intended to evaluate the efficacy of a 48 hour antibiotic microbial prophylaxis (AMP) protocol as compared with a 72 hour AMP protocol. OVERVIEW OF LITERATURE: The current guideline for the prevention of surgical site infection (SSI) suggests the AMP should not exceed 24 hours after clean surgery like spinal surgery. But there exist some confusion in real clinical practice about the duration of postoperative antibiotic administration because the evidence of the guideline was not robust. METHODS: The subjects were 548 patients who underwent spinal surgery at our department from April 2007 to December 2008. The patients were classified into two groups according to the prophylaxis protocol: group A, for which AMP was employed for 72 hours postoperatively and group B, for which AMP was employed for 48 hours postoperatively. Five hundred two patients out of 548 patients were followed until 6 months postoperatively. The incidence of SSI in the two groups was analyzed. RESULTS: The overall infection rate was 0.8%. There was no significant difference in infection rate between the two groups. The overall infection rate for the patients who underwent instrumented fusion was 0.9%. There was no significant difference in the infection rate between the patients of the two groups who underwent instrumented fusion. CONCLUSIONS: AMP for 48 hours is as efficient as AMP for 72 hours.

Comparison between Operated Muscular Dystrophy and Spinal Muscular Atrophy Patients in terms of Radiological, Pulmonary and Functional Outcomes

STUDY DESIGN: Retrospective comparative study. PURPOSE: To study and compare the surgical outcomes of muscular dystrophy (MD) and spinal muscle atrophy (SMA). OVERVIEW OF LITERATURE: There are few reports that have evaluated and compared the surgical outcomes of MD and SMA patients. METHODS: The patients (n = 35) were divided into two groups: a MD group with 24 patients and a SMA group with 11 patients. The average follow-up period was 21 months. All patients were operated for scoliosis correction using posterior instrumentation and fusion. In the immediate postoperative period, all efforts were made to reduce the pulmonary complications using non-invasive positive pressure ventilation and a coughing assist devices. The patients were evaluated by radiograph in terms of the Cobb's angle, pelvic obliquity, T1 translation, thoracic kyphosis and lumbar lordosis. The pulmonary function and self-image satisfaction were also assessed. RESULTS: There was a lower correction rate in the MD group (41.5%) than in the SMA group (48.3%), even though the curves were smaller in the MD group. The correction in the pelvic obliquity was significantly better in the SMA group (p = 0.03). The predicted vital capacity showed a 4% reduction in the MD group 1 year after surgery, while the SMA group showed a 10% reduction. The peak cough flow and end tidal PCO2 did not deteriorate and were well maintained. The average score for the improvement in self-image satisfaction postoperatively was 3.96 and 4.64 for the MD and SMA groups, respectively. The total complication rate was 45.7%; 14.3% of which were respiratory-related. CONCLUSIONS: Surgical intervention for MD and SMA may be performed safely in patients with a very low forced vital capacity (< 30%) through aggressive preoperative and postoperative rehabilitation efforts.

Prevention of New Vertebral Fractures after Treatment with Risedronate, Alendronate or Calcium Carbonate in Patients with Osteoporotic Compression Fracture Treated with Cement Augmentation / 대한정형외과학회잡지

PURPOSE: To evaluate the rate of new fractures of the spine after risedronate, alendronate or calcium carbonate in patients who had vertebroplasty or kyphoplasty due to compression fracture. MATERIALS AND METHODS: We studied 292 patients with osteoporotic compression fractures who had received vertebroplasty or kyophoplasty between June 2003 and October 2007. Of these, 199 were evaluated for new fractures of the spine after treatment with risedronate, alendronate or calcium carbonate. Patients (n=199) were assigned to 1 of 4 groups: No treatment (n=71), risendronate (n=64), alendronate (n=42) or calcium carbonate group (n=22). RESULTS: New fractures of the spine were morphogenically found in 19 patients (26.8%) in the no treatment group, in 11 (17.2%) in the risendronate group, in 8 (19.1%) in the alendronate group, in 5 (22.8%) in the calcium carbonate group. Symptomatically, they were found in 6 patients (8.5%) in the no treatment group, in 4 (6.3%) in the risendronate group, in 3 patients (7.1%) in the alendronate group, and in 2 patients (9.1%) in the calcium carbonate group. CONCLUSION: At one year follow up none of the differences between groups in new fracture rates of the spine were statistically significant.

Multiple Levels of Lumbar Spondylolysis: A Case Report

We report here on an unusual case of multiple levels of asymmetric lumbar spondylolysis in a 19-year-old woman. The patient had severe low back pain of increasing intensity with lumbar instability, which was evident on the dynamic radiographs. MRI demonstrated the presence of abnormalities and the three dimensional CT scan revealed asymmetric complete spondylolysis at the left L2, L3 and L4 levels and the right L1, L2 and L3 levels. This case was treated surgically by posterior and posterolateral fusion at L2-3-4 with intersegmental fixation using pedicle screws and an auto iliac bone graft. The patient was relieved of her low back pain after the surgery.

Comparison of Surgical Outcomes in Thoracolumbar Fractures Operated with Posterior Constructs Having Varying Fixation Length with Selective Anterior Fusion

PURPOSE: Surgical treatment in the case of thoracolumbar burst fractures is very controversial. Posterior instrumentation is most frequently used, however, but the number of levels to be instrumented still remains a matter of debate. MATERIALS AND METHODS: A total of 94 patients who had a single burst fracture between T11 and L2 were selected and were managed using posterior instrumentation with anterior fusion when necessary. They were divided into three groups as follows; Group I (n = 28) included patients who were operated by intermediate segment fixation, Group II (n = 32) included patients operated by long segment fixation, and Group III (n = 34) included those operated by intermediate segment fixation with a pair of additional screws in the fractured vertebra. The mean follow-up period was twenty one months. The outcomes were analyzed in terms of kyphosis angle (KA), regional kyphosis angle (RA), sagittal index (SI), anterior height compression rate, Frankel classification, and Oswestry Disability Index questionnaire. RESULTS: In Groups II and III, the correction values of KA, RA, and SI were much better than in Group I. At the final follow up, the correction values of KA (6.3 and 12.1, respectively) and SI (6.2 and 12.0, respectively) were in Groups II and III found to be better in the latter. CONCLUSION: The intermediate segment fixation with an additional pair of screws at the fracture level vertebra gives results that are comparable or even better than long segment fixation and gives an advantage of preserving an extra mobile segment.

Intraspinal Clear Cell Meningioma: A Case Report / 대한정형외과학회잡지

Meningioma is one of the most common tumors of the spinal canal. Spinal meningiomas are usually found in the thoracic spine and intradural extramedullary space. Intraspinal clear cell meningiomas are a rare histological variant. Fewer than 20 intraspinal cases have been reported in the literature and only two cases have been reported in the Korean literature, but there is no report available in the Korean orthopedic literature. We report here on a case of an intraspinal clear cell meningioma that was found in the thoracic region and it was completely resected. The nonspecific MR imaging characteristics make the diagnosis of this tumor difficult. Histological examination must be used to differentiate clear cell meningiomas from other tumors. Clear cell meningioma represents an aggressive variant of meningiomas, and surgical reatment and adjuvant radiotherapy are though to be essential. Further more, long term follow-up observation will be needed for detecting recurrence of clear cell meningioma.

Risk Factors Associated with the Halo Phenomenon after Lumbar Fusion Surgery and its Clinical Significance

STUDY DESIGN: Retrospective study. PURPOSE: First, to examine the association between bone mineral density (BMD) and the halo phenomenon, and second, to investigate risk factors predisposing to the halo phenomenon and its correlation with clinical outcomes. OVERVIEW OF LITERATURE: The few in vivo studies regarding the relationship between pedicle screw stability and BMD have shown conflicting results. METHODS: Forty-four female patients who underwent spine fusion surgery due to spinal stenosis were included in this study. The halo phenomenon and fusion state were evaluated through plain radiographs performed immediately after surgery and through the final outpatient follow-up examination. BMD, osteoarthritis grade in the hip and knee joints, and surgical outcome were also evaluated. RESULTS: BMD was not related to the halo phenomenon, but age, absence of osteoarthritis in the knee, and non-union state were found to be significant risk factors for the halo phenomenon. However, the radiological halo phenomenon did not correlate with clinical outcome (visual analogue scale for back pain and leg pain). CONCLUSIONS: The halo phenomenon is a simple phenomenon that can develop during follow-up after pedicle screw fixation. It does not influence clinical outcomes, and thus it is thought that hydroxyapatite coating screws, expandable screws, cement augmentation, and additional surgeries are not required, if their purpose is to prevent the halo phenomenon.

Incidence and Risk Factors Associated with Superior Mesenteric Artery Syndrome following Surgical Correction of Scoliosis

STUDY DESIGN: Retrospective study. PURPOSE: To more accurately determine the incidence and clarify risk factors. OVERVIEW OF LITERATURE: Superior mesenteric artery syndrome is one of the possible complications following correctional operation for scoliosis. However, when preliminary symptoms are vague, the diagnosis of superior mesenteric artery syndrome may be easily missed. METHODS: We conducted a retrospective study using clinical data from 118 patients (43 men and 75 women) who underwent correctional operations for scoliosis between September 2001 and August 2007. The mean patient age was 15.9 years (range 9~24 years). The risk factors under scrutiny were the patient body mass index (BMI), change in Cobb's angle, and trunk length. RESULTS: The incidence of subjects confirmed to have obstruction was 2.5%. However, the rate increased to 7.6% with the inclusion of the 6 subjects who only showed clinical symptoms of obstruction without confirmative study. The BMI for the asymptomatic and symptomatic groups were 18.4+/-3.4 and 14.6+/-3, respectively. The change in Cobb's angle for the asymptomatic and symptomatic groups were 24.8+/-13.6degrees and 23.4+/-9.1degrees, respectively. The change in trunk length for the asymptomatic and symptomatic groups were 2.3+/-2.1 cm and 4.5+/-4.8 cm, respectively. Differences in Cobb's angle and the change in trunk length between the two groups did not reach statistical significance, although there was a greater increase in trunk length for the symptomatic group than for the asymptomatic group. CONCLUSIONS: Our study shows that the incidence of superior mesenteric artery syndrome may be greater than the previously accepted rate of 4.7%. Therefore, in the face of any early signs or symptoms of superior mesenteric artery syndrome, prompt recognition and treatment are necessary.

Polyaxial Screws with Thick Rod versus Monoaxial Screws with Thin Rod in Video-Assisted Thoracoscopic Scoliosis Surgery (VATS) / 대한척추외과학회지

STUDY DESIGN: Prospective controlled cohort study OBJECTIVE: To analyze the clinical outcome of video-assisted thoracoscopic surgery (VATS) between two different types of implants. SUMMARY OF LITERATURE REVIEW: The problem of correction loss has been reported with VATS, and different screws and rods have been developed to overcome this problem. Different implants will have varying effects in correctional outcome after VATS. MATERIALS AND METHODS: A total of 39 cases of idiopathic adolescent scoliosis treated with VATS between June 2001 and January 2005 were included in the study (mono-axial screws and a 4.5 mm rod: thin rod group=19 cases; poly-axial reduction screws and a 5.5 mm diameter rod: thick rod group=20 cases). All patients were followed for over 2 years postoperatively. For the comparison of surgical outcomes between the two groups, radiographic measurements were performed in the coronal and sagittal planes. RESULTS: Preoperative scoliosis angle (thin rod group 49.8degrees, thick rod group 47.1degrees), age, BMI, Risser stage, union time, operative time, and blood loss showed no statistical difference between the two groups. Postoperative average correction rate of scoliosis angle was 69% (15.8degrees) in the thin rod group and 70% (14.1degrees) in the thick rod group. However, correction rate after 2 years was 51% (24.5degrees) in the thin rod group and 60% (18.7degrees) in the thick rod group, showing statistically significant difference. There was a tendency toward correction loss in the thin rod group (8.7degrees vs. 4.6degrees p=0.0057). CONCLUSION: Postoperative correction rate was satisfactory in both groups. However, the thin rod group showed substantial correction loss. Therefore, poly-axial screws and thick rods are more suitable in VATS correction of scoliosis.

Analysis of the Factors Influencing on the Postoperative Results of Radial Head Fractures Combined with Elbow Dislocation / 대한정형외과학회잡지

PURPOSE: Radial head fractures are the most common elbow fractures in adults, and are often accompanied with elbow dislocation resulting in various complications. This study examined the outcome of surgical treatment of a radial head fracture and its prognostic factors. MATERIALS AND METHODS: From January 1997 to February 2004, a retrospective analysis was performed on 25 radial head fracture patients with an elbow dislocation, also including elbow fracture, whose follow-up data could be obtained for more than 12 months. The surgical results were evaluated according to the prognostic factors and the Mayo Elbow Performance Index, which assessed the elbow joint function and pain. RESULTS: According to the Mayo Elbow Performance Index, the results were excellent in 11 cases, good in 5 cases, fair in 5 cases, and poor in 4 cases. Cases with post-surgical elbow joint instability showed statistically meaningful poor outcomes. However, there were good in the groups without an accompanied fracture, with no open fracture, type II and III Mason classification, and fixation period 4 weeks or less. Correlation analysis revealed a younger age and shorter immobilization period to have better results, and the immobilization period showed the strongest correlations with the Mayo Elbow Performance index. CONCLUSION: In conclusion, younger age, less severe injury in the initial event and a shorter immobilization period are good prognostic factors in radial head fractures combined elbow dislocations.

The Incidence of New Vertebral Compression Fractures in Women after Kyphoplasty and Factors Involved

PURPOSE: To identify the incidence of new vertebral compression fractures in women after kyphoplasty and to analyze influential factors in these patients. MATERIALS AMD METHODS: One hundred and eleven consecutive female patients with osteoporotic vertebral compression fractures (VCFs) underwent kyphoplasty at 137 levels. These patients were followed for 15.2 months postoperatively. For the survey of new vertebral compression fractures, medical records and x-rays were reviewed, and telephone interviews were conducted with all patients. RESULTS: During that time 20 (18%) patients developed new VCFs. The rate of occurrence of new VCFs in one year was 15.5% using a Kaplan-Meier curve. Body mass index (BMI), symptom duration and kyphoplasty level were the statistically significant factors between the patient groups both with and without new VCFs after kyphoplasty. In the comparison between the adjacent and remote new VCF groups, the adjacent new VCF group showed a larger amount of polymethyl methacrylate (PMMA) use during kyphoplasty (p<0.05). Before kyphoplasty, 9.9% of the patients had been prescribed medication for osteoporosis, and 93.7% of the patients started or continued medication after kyphoplasty. The development of new VCFs was affected by the number of vertebrae involved in the kyphoplasty. However, the lower incidence rate (15.5%) of new compression fractures might be due to a greater percentage (93.7% in our study) of patients taking anti-osteoporotic medication before and/or after kyphoplasty. CONCLUSION: When kyphoplasty is planned for the management of patients with osteoporotic VCFs, the application of a small amount of PMMA can be considered in order to lower the risk of new fractures in adjacent vertebrae. The postoperative use of anti- osteoporotic medication is recommended for the prevention of new VCFs.

A Comparison of Bone Mineral Density between Adolescent Idiopathic Scoliosis and Neuromuscular Scoliosis / 대한척추외과학회지

STUDY DESIGN: A Cross-sectional study OBJECTIVE: This study evaluated the degree of osteoporosis of adolescent idiopathic scoliosis (AIS) and neuromuscular scoliosis (NMS) and compared bone mineral density. LITERATURE REVIEW: In osteoporosis, bone mineral density was not as dense even in the outer layer, and the cortex was thinner than normal. A larger screw doss not enhance the screw stability and can break the thin cortex in osteoporotic vertebrae. MATERIALS AND METHODS: This study reviewed the cases of consecutive patients with scoliosis, who underwent an osteoporosis examination before surgery between August 2004 and June 2006. The osteoporosis examination included DEXA in lumbar vertebrae and proximal femur. The mean osteoporotic degree of both femurs was recorded. The data was analyzed using the BMD(bone mineral density, g/cm(2)) and Z value of the BMD according to age, gender, and ethnicity. RESULTS: The mean degree of the coronal deformity was 48.4 in AIS and 62.9 in NMS. A comparison of both groups revealed a significantly lower BMD and Z value of Femur, and BMD of the vertebra in the NMS patients (p<0.05). A comparison between AIS and non-ambulant NMS showed that all parameters were significantly lower in the non-ambulant NMS (p<0.05). Neither the BMD and Z value of the AIS nor the NMS were associated with the severity of the spinal deformity. CONCLUSION: A lower BMD was measured in patients with non ambulant NMS than AIS. The degree of the osteoporosis, particularly of the non ambulant NMS patients need to be considered before undergoing surgery.