Different Pattern of T-Score Discordance between Patients with Atypical Femoral Fracture and Femur Neck Fracture

Background@#Our study evaluated the prevalence and pattern of T-score discordance between the spine and hip in Korean patients with atypical femoral fracture (AFF) and femur neck fracture (FNF). @*Methods@#A total of 49 patients (all women) who were treated for AFF and 1:3 matched 147 female patients with FNF were included from January 2012 to August 2022. A discordance of more than 1.5 between lumbar spine and femur neck bone mineral density (BMD) was defined as a difference and divided into 3 groups: lumbar low (LL; lumbar BMD is less than femur neck BMD), no discordance (ND), and femur neck low (FL; femur neck BMD is less than lumbar BMD). We compared the prevalence and pattern of discordance between 2 groups, and the associated risk factors of T-score discordance among the subjects were evaluated using regression analysis. @*Results@#The prevalence of discordance was significantly higher in patients with AFF (51%) than in those with FNF (25.2%; p<0.001). LL discordance was found in 46.9% of the patients with AFF but only 4.8% in those with FNF. Conversely, FL discordance was found in 4.1% of the patients with AFF and 20.4% in those with FNF, respectively. No specific risk factor was found as T-score discordance in the 2 groups. @*Conclusions@#Clinicians should be aware that the pattern of T-score discordance can vary depending on the location of osteoporotic fractures. In addition, a longitudinal study would be necessary to verify the pattern of T-score discordance related to the osteoporotic fracture location.

Prevalence and Risk Factors of T-Score Spine-Hip Discordance in Patients with Osteoporotic Vertebral Compression Fracture

Background@#T-score discordance between the spine and hip is commonly observed when dual energy X-ray absorptiometry (DXA) is used to diagnose osteoporosis. However, information is scarce regarding the prevalence and risk factors for this problem in Korea. This study evaluated the prevalence of major/minor discordance and associated risk factors in elderly Korean patients with osteoporotic vertebral compression fractures (OVCFs). @*Methods@#This study included 200 patients (37 men, 163 women) treated for thoracic or lumbar compression fractures between January 2015 and August 2021. DXA was performed to examine T‐scores and determine the prevalence of discordance, defined as a difference between the T-score categories of the femur and spine in the same individual. The t-tests, χ2 tests, and regression analyses were used to assess the associated risk factors of T-score discordance among the subjects. @*Results@#T-score concordance, minor discordance, and major discordance were observed in 137 (68.5%), 59 (29.5%), and 4 (2%) patients with OVCFs, respectively. The spinal T-score was lower than the femoral T-score in all major discordance and 81.3% (48/59) of minor discordant cases. Overall, the only factor related to T-score discordance was the age at fracture (odds ratio, -0.01; P=0.014). @*Conclusions@#The results of this study showed that a significant number of subjects (31.5%) showed spine-hip discordance, even with a mean age in their 80s. More attention should be paid to the appropriate evaluation and management of elderly patients with OVCFs. Moreover, a longitudinal study is necessary to verify the clinical importance of T-score discordance in this population.

Does Bone Mineral Density Differ between Fan-Beam and Pencil-Beam?: A Meta-Analysis and Systemic Review

Background@#Dual energy X-ray absorptiometry (DXA) has evolved from pencil-beam (PB) to narrow fan-beam (FB) densitometers. We performed a meta-analysis of the available observational studies to determine how different modes of DXA affect bone mineral density (BMD) measurements. @*Methods@#A total of 1,233 patients (808 women) from 14 cohort studies were included. We evaluated the differences in BMD according to the DXA mode: PB and FB. Additionally, we evaluated the differences in BMD between the 2 types of FB mode: FB (Prodigy) and the most recent FB (iDXA). Pairwise meta-analysis was performed, and weighted mean differences (WMD) were calculated for (total lumbar, total hip, and total body). @*Results@#No significant difference was observed in total lumbar (pooled WMD, -0.013; P=0.152) and total hip BMD (pooled WMD, -0.01; P=0.889), between PB and FB. However, total body BMD was significantly lower in the PB compared to the FB group (pooled WMD, -0.014; P=0.024). No significant difference was observed in lumbar BMD (pooled WMD, -0.006; P=0.567), total hip (pooled WMD, -0.002; P=0.821), and total body (pooled WMD, 0.015; P=0.109), between Prodigy and iDXA. @*Conclusions@#The results of this study warrant the recommendation that correction equations should not be used when comparing BMD from different modes. Further research is still needed to highlight the ways in which differences between DXA systems can be minimized.

Risk Factors Predicting New Compression Fractures in Patients with Osteoporotic Vertebral Compression Fractures

STUDY DESIGN: A retrospective study. OBJECTIVES: To investigate the risk factors associated with new compression fractures in patients with osteoporotic vertebral compression fractures. SUMMARY OF LITERATURE REVIEW: Previous studies have reported that a history of osteoporotic vertebral fractures and decreased bone mineral density were risk factors for new compression fractures. It is not certain whether vertebroplasty is a risk factor for new compression vertebral fractures. MATERIALS AND METHODS: This retrospective study included a total of 52 patients who were diagnosed with an osteoporotic vertebral compression fracture and could be followed up for at least 1 year. Age, sex, bone mineral density, body mass index, osteoporosis treatment, fat infiltration of the back muscles, the sagittal index, vertebroplasty, and underlying diabetes mellitus or hypertension were compared between patients who developed new compression fractures during 1 year of follow-up and those who did not. For statistical analysis, the t-test and chi-square test were used to analyz ethe relationship of each factor with osteoporotic vertebral compression fracture incidence, and multiple logistic regression analysis was performed to analyze multifactorial explanatory factors. RESULTS: No significant differences were found between the 2 groups regarding sex, underlying disease, the sagittal index, and fat infiltration of the back muscles. Patients who developed a new compression fracture were significantly older (p=0.011), had a lower body mass index (p=0.001), had lower bone mineral density (p=0.008), and were more likely to have taken osteoporosis medication for less than 6 months (including no medication, p=0.019). The logistic regression analysis showed that the risk of developing new compression fractures was significantly elevated in patients with a low body mass index (odds ratio [OR]=0.69, p=0.02), bone mineral density (OR=0.43, p=0.005), and less than 6 months of osteoporosis medication use (including no medication, OR=1.083, p=0.041). CONCLUSIONS: The risk of developing new compression fractures in patients with osteoporotic vertebral compression fractures was associated with body mass index, bone mineral density, and having taken osteoporosis medication for less than 6 months.

Comparison of the Efficacy and Safety Profiles of a Pelubi Sustained Release Tab Versus a Pelubi Tab in Patients with Chronic Back Pain: A Randomized, Double-Blind, Multi-Institution Phase III Study

STUDY DESIGN: A randomized, double-blind, multi-institution, phase III study. OBJECTIVES: To evaluate the efficacy and safety of the Pelubi Sustained Release (SR) Tab in patients with chronic back pain, in comparison with the Pelubi Tab, whose efficacy has already been approved, a phase 3 clinical trial was conducted. SUMMARY OF LITERATURE REVIEW: The Pelubi Tab Has shown clinical efficacy in patients with back pain. MATERIALS AND METHODS: From April 11, 2014 to July 24, 2014, 166 chronic back pain patients were recruited as subjects through a multi-institution, double-blind, random sample. We compared the experimental and control groups' clinical efficacy, which was estimated by the 100-mm Pain Visual Analog Scale (VAS) after 28 days of medication. We also compared the treatment efficacy of both drugs by using a variation of the Oswestry Disability Index (ODI) and Physician Global Assessment (PGA), with the total usage of relief medicine. The side effects and clinical pathology were also noted. RESULTS: Neither group showed a significant difference in 100-mm Pain VAS or ODI variation (p=0.1702, p=0.9041). There was no statistically significant difference between the experimental group and the control group in PGA or total usage of relief medicine. The ODI and PGA variation were not worse in the experimental group than the control group. The two groups showed no significant differences in side effects (p=0.9708). CONCLUSIONS: This study found that the Pelubi SR Tab applied to back pain patients was not inferior to the Pelubi Tab and did not show any significant difference in terms of safety. The Pelubi SR Tab can be used with the same expectation of safety as the Pelubi Tab.

Changes in Clinical Symptoms, Functions, and the Median Nerve Cross-Sectional Area at the Carpal Tunnel Inlet after Open Carpal Tunnel Release

BACKGROUND: The aim of this study was to investigate the relationship between clinical symptoms and cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet before and after open carpal tunnel release (CTR). METHODS: Thirty-two patients (53 hands) that underwent open CTR for idiopathic carpal tunnel syndrome were prospectively enrolled. Median nerve CSA at the carpal tunnel inlet was measured preoperatively and at 2 and 12 weeks after CTR by high resolution ultrasonography. The Boston carpal tunnel questionnaire (BCTQ) was also completed at these times. RESULTS: BCTQ symptom (BCTQ-S) score was significantly improved at 2 weeks postoperatively, but BCTQ function (BCTQ-F) score and CSA were significantly improved at 12 weeks postoperatively. Preoperative CSA was significantly correlated with preoperative BCTQ-S and BCTQ-F scores but was not significantly correlated with postoperative BCTQ scores or postoperative changes in BCTQ scores. Postoperative median nerve CSA was not significantly correlated with postoperative BCTQ-S or BCTQ-F scores, and postoperative changes in median nerve CSA were not significantly correlated with postoperative changes in BCTQ-S or BCTQ-F scores. CONCLUSIONS: The study shows clinical symptoms resolve rapidly after open CTR, but median nerve swelling and clinical function take several months to recover. In addition, preoperative median nerve swelling might predict preoperative severities of clinical symptoms and functional disabilities. However, postoperative reductions in median nerve swelling were not found to reflect postoperative reductions in clinical symptoms or functional disabilities.

Progression of Compression and Related Factors in Conservative Management of Osteoporotic Vertebral Compression Fractures

PURPOSE: The purpose of this study is to determine the ideal period of brace application for thoracolumbar (T10-L2) osteoporotic vertebral compression fracture (OVCF) based on the progression of the vertebral compression with passage of time and to evaluate the factors associated with progression of thoracolumbar OVCF, when treated conservatively. MATERIALS AND METHODS: This retrospective study included a total of 46 patients who were diagnosed with thoracolumbar OVCF and could be followed-up for at least 6 months. In this study, the increase of compression rate and the mean slope of compression rate per weeks were compared between two periods (from diagnosed date to 8 weeks and from 8 weeks to 6 months), as the standard point. Age, bone mineral density (BMD), osteoporosis treatment after injury, diabetes mellitus (DM) as underlying disease were also compared between two groups (setting up 15% as standard point of increase of compression rate, or =15%). Statistical analyses were performed using the paired t-test to assess the increase of compression rate and using the linear mixed model to assess the mean slope change. The relationships between the factors and progression of compression were analyzed using t-test, chi-square test, and logistic regression analysis. RESULTS: The increase of compression rate was 13.03% and 1.97% in each period and the difference between those two periods was 11.06% (p=0.00). At 8 weeks of follow-up, the mean slope was reduced by 1.12 (p=0.00). No statistically significant difference in related factors was observed between two groups. CONCLUSION: Considering the increase of compression rate with passage of time, brace should be applied strictly for an initial 8 weeks. And age, BMD, osteoporosis treatment after injury, and DM as underlying disease are not predictors of progression of compression in vertebral fractures.

Clinical Outcome of Simple Discectomy for Recurrent Lumbar Disc Herniation

STUDY DESIGN: This is a retrospective study. OBJECTIVES: To analyze the clinical outcomes of simple discectomy in patients with recurrent lumbar disc herniation. SUMMARY OF LITERATURE REVIEW: There are two methods of studying the treatment of recurrent lumbar disc herniation. The first type of study considers fusion for the prevention of complications such as postoperative lumbar segmental instability and persistent back pain. The second type of study assumes that simple discectomy without fusion is sufficient in the surgical management of recurrent lumbar disc herniation. MATERIALS AND METHODS: Sixteen patients who underwent simple discectomy due to recurrent lumbar disc herniation were followed up over 3 years. The mean age was 52.8 years (38-68 years). The mean follow-up period was 75.4 months (36-144 months). VAS scores for back pain and radiating lower leg pain were each compared pre- and post-operatively. The Oswestry Disability Index (ODI) was used to analyze the clinical outcome. A modified MacNab's outcome was used to evaluate patient satisfaction. Subjective survey data in a Delphi checklist was reviewed to verify clinical lumbar instability. RESULTS: The mean back pain VAS score showed 87.5% improvement (p<0.001). The mean lower leg VAS score showed 89% improvement (p<0.001). The mean preoperative ODI score was 29.9, and the mean score checked at the last follow up was 3.5. It thus showed 88.3% improvement (p<0.001). Excellent or good satisfaction was reported by fourteen patients (87.5%), and clinical lumbar instability was identified in one patient (6.3%). CONCLUSIONS: Simple discectomy without fusion is one of treatment option for recurrent disc herniation without instability.

Treatment of the Distal Radius Fractures in the Elderly Patients

Distal radius fractures are one of the most common types of fractures in the elderly. It is well documented that increased risk of a distal radius fracture in older patients is associated with decreased bone mineral density. Also, low bone mineral density increased severity of fracture and instability of fracture after reduction. Fracture displacement in the elderly does not necessarily result in functional impairment. Therefore, conservative treatment has been a mainstay treatment even in unstable fracture in the elderly. However, there is an increasing trend toward operative treatment recently, because functional demand increased in the elderly due to active life style and volar locking plate fixation enables the elderly early return to daily activity even in osteoporotic distal radius fracture.

Survival Analysis of Conservative Treatement in Osteoporotic Vertebral Fracture

STUDY DESIGN: Prospective study. OBJECTIVES: To define the prognostic factors by analyzing the survival rates of osteoporotic vertebral fracture treated by conservative management. SUMMARY OF THE LITERATURE REVIEW: Due to an increasing elder population, many recent studies of osteoporosis have been done; pointing out that osteoporotic vertebral fracture may produce serious complications. However, there is nothing obviously demonstrated in both the management and prognosis of the osteoporotic vertebral fracture. MATERIALS AND METHODS: Survival analysis was done for 130 patients who had undergone conservative management for a single level vertebral fracture. Univariant and multivariant survival analysis was done for age at trauma, sex, body mass index (BMI), bone mineral density (BMD), smoking, diabetic history, fracture level, fracture type, vertebral compression ratio and regional Cobb's angle. RESULTS: Survival rate for conservative management was 70.7%. Univariant analysis for survival rate revealed significantly inferior results for age over 78 (p=0.008), T score< -3.5 (p=0.047), and crush or biconcave type than wedge type (p=0.021). Only the age factor showed significance in multivariant analysis (p=0.025, Hazard ratio=2.08). CONCLUSION: Conservative management in a single level osteoporotic vertebral fracture, showed a survival rate of 70.7% and age was the most important factor in conservative management. We should notice that age of more than 78 years is at high risk for failure in conservative management of vertebral fracture.

The Availability of Autogenous Bicortical Iliac Bone Graft in Anterior Cervical Interbody Fusion

STUDY DESIGN: Retrospective study. OBJECTIVES: To demonstrate the fusion rate, degree of subsidence and donor site morbidity of anterior cervical interbody fusion with autogenous bicortical iliac bone graft and anterior cervical locking plate. SUMMARY OF THE LITERATURE REVIEW: In anterior cervical discectomy and fusion with autogenous tricortical iliac bone graft, a large percentage of patients report chronic donor site pain. MATERIALS AND METHODS: Retrospective research was done for 39 patients who underwent anterior cervical interbody fusion with autogenous bicortical iliac bone graft, from January 2006 to July 2011, with a follow up period of longer than 1 year. Fusion rates and subsidece of the graft is estimated with radiographs. Neck pain and donor site pain was estimated with visual analogue scale (VAS) and dysfunction was estimated with the neck disability index (NDI). RESULTS: A 95% of patients who underwent anterior cervical interbody fusion with autogenous bicortical iliac bone graft revealed definitive fusion with little amount of subsidence. The mean VAS score was 0.7 on the donor site and the mean NDI score was 3.8 at the final visit. There was excellent clinical outcome without complication at the donor site or the recipient site. CONCLUSIONS: Anterior cervical interbody fusion with autogenous bicortical iliac bone graft showed high fusion rates and minimal subsidence with excellent clinical outcomes. Therefore, bicortical iliac bone graft is an effective operational procedure in anterior cervical interbody fusion.

Acute Spontaneous Cervical Spinal Epidural Hematoma with Spontaneous Resolution: A Case Report

STUDY DESIGN: This is a case report. OBJECTIVES: We wanted to report on the spontaneous dissolution of acute spontaneous epidural hematoma of the cervical spine and the effectiveness of conservative treatments, in the cases where the symptoms related to spontaneous epidural hematoma improve by themselves in a short period. SUMMARY OF LITERATURE REVIEW: Cases of acute spontaneous epidural hematoma of the cervical spine are rarely reported; surgical decompression procedures have been performed in most of the cases as treatment. However, there are some reported cases of hematoma dissolving spontaneously after a certain period of conservative treatment. MATERIALS AND METHODS: A 29 year-old female, who had no history of recent trauma, appealed neck pain with radiating pain in her upper right extremity due to acute epidural hematoma of the cervical spine which was diagnosed with MRI. The neck pain and radiating pain showed early recovery and gradual improvement during a period of the following 7 days after occurrence. MRI studies were done after 3 days, 7days, and 1 month from the day of occurrence of the symptoms. RESULTS: In comparing MRI studies there were significant decreases in the sizes of hematoma, which implied spontaneous dissolution. Almost all the symptoms related to acute spontaneous epidural hematoma vanished after a 1-month period of conservative treatment. CONCLUSIONS: Decompressive surgical procedure may not be necessary, if the symptoms related to spontaneous epidural hematoma improve by themselves in short period of conservative treatment.

Radiological and Clinical Outcome after Simple Discectomy of Central Massive Lumbar Disc Herniation

STUDY DESIGN: This is a retrospective case control study. OBJECTIVES: To analyze our results following simple discectomy of central massive disc herniation focusing on instability for the usefulness of intervertebral fusion. SUMMARY OF LITERATURE REVIEW: Lumbar instability is a complication of central massive disc herniation. However, there is limited evidence on the correlation between lumbar instability and loss of disc material. MATERIALS AND METHODS: A total of 25 patients who had undergone discectomy for a single-level lumbar disc herniation were followed up for two years. The clinical group (group A) included 12 patients that had a compromised canal with greater than 50% of the herniated disc, while the central axis of the herniated disc was less than 20% deviated from the center axis of the spinal canal, as seen on MRI. The control group (group B) had 13 patients that had a compromised canal with less than 50% of the herniated disc while their axis was more than 20% deviated from the center axis of the spinal canal. Clinical and radiologic instability, pain and functional disability were compared between the two groups. RESULTS: No differences was found between the two groups in clinical instability, radiological instability, visual analogue scale (VAS), and the Oswestry disability index (ODI). CONCLUSIONS: Central massive disc herniation after discectomy did not show a significant difference in clinical or radiological instability from that of other herniation types.

Reliability and Validity of Thoracolumbar Injury Classification and Severity Score (TLICS)

STUDY DESIGN: A new classification system for throacolumbar spine injury, Thoracolumbar Injury Classification and Severity Score (TLICS) was evaluated retrospectively. PURPOSE: To evaluate intrarater and interrater reliability of newly proposed TLICS schemes and to estimate validity of TLICS's final treatment recommendation. OVERVIEW OF LITERATURE: Despite numerous literature about thoracolumbar spine injury classifications, there is no consensus regarding the optimal system. METHODS: Using plain radiographs, computed tomography scanning, magnetic resonance imaging, and medical records, 3 clssifiers, consisting of 2 spine surgeons and 1 senior orthopaedic surgery resident, reviewed 114 clinical thoracolumbar spine injury cases retrospectively to classify and calculate injury severity score according to TLICS. This process were repeated on 4 weeks intervals and the scores were then compared with type of treatment that patient ultimately received. RESULTS: The intrarater reliability of TLICS was substantial agreement on total score and injury morphology, almost perfect agreement on integrity of the posterior ligament complex (PLC) and neurologic status. The interrater reliability was substantial agreement on injury morphology and integrity of the PLC, moderate agreement on total score, almost perfect agreement on neurologic status. The TLICS schems exhibited satisfactory overall validity in terms of clinical decision making. CONCLUSIONS: The TLICS was demonstrated acceptable intrarater and interrater reliability and satisfactory validity in terms of treatment recommendation.

The Factors that Affect the Deformity Correction of Vertebral Body during Kyphoplasty of Osteoporotic Vertebral Compression Fracture

PURPOSE: To study which factors affect the deformity correction of vertebral body during kyphoplasty procedure. MATERIALS AND METHODS: 25 osteoporotic vertebral compression fractures were treated with balloon kyphoplasty from October 2006 to May 2007. Lateral radiographs were taken at 5 different stages with preoperative lateral decubitus position, after placing the patient in prone position on an operation table, after inflating balloon, after deflation and removal of the balloon, after inserting the cement. Then we analyzed the compression ratios and kyphotic angles of the vertebral bodies in each stage. RESULTS: Placing the patient in prone position showed significant postural reduction in kyphotic angle and restorement of the anterior and middle body height. The inflation of the balloon demonstrated significant reduction of kyphotic angle and restorement of the anterior and middle body height. After the deflation, anterior and middle body height has decreased significantly. After the deflation, the kyphotic angle and the anterior and middle body heights were not restored signigicantly compared with those of initial prone position. CONCLUSION: Vertebral height and kyphotic angle were partially recovered by inflating the balloon, but the correction was lost after deflating the balloon. Statistically, the body deformity was not restored significantly after deflating the balloon compared with that of intraoperative prone position. Therefore, we concluded that, in kyphoplasty of osteoporotic compression fractures, the postural reduction is the most important factor in deformity correction of fractured vertebral bodies.

The Relationship between Progression of Body Collapse and MRI Findings in Osteoporotic Stable Thoracolumbar Fractures

PURPOSE: To find out the relationship between the initial Magnetic Resonance Image (MRI) findings and the progression of vertebra collapse when treated with Jewett brace in osteoporotic stable thoracolumbar fractures. MATERIALS AND METHODS: We divided 38 cases of 37 patients of thoracolumbar osteoporotic stable thoracolumbar fractures who were treated with Jewett brace into two groups. One group was composed of those body collapse progressed more than 10% compared with the initial state, and the other group less than 10%. We analyzed the relationships between the progression of collapse and the superior endplate fractures, the fracture line extending to posterior cortex, the size of bone marrow edema, the signal intensity on T1 and T2 weighted MR images, the presence of paravertebral hematoma, and the degree of posterior extensor muscle atrophy using MR images. RESULTS: The body collapse was more likely to progress when there was superior endplate fracture, when it showed larger size of bone marrow edema on T1 weighted image, and transverse low signal on T2 weighted image. But extending of fracture line to posterior cortex, presence of paravertebral hematoma, and degree of posterior extensor muscle atrophy did not show any statistical correlations to progression of collapse. CONCLUSION: The body collapse is more likely to progress when there was superior endplate fracture, larger low signal on T1 weighted image and low signal on T2 weighted image at initial MRI treated with Jewett brace.

Comparative Study of Intramedullary Nailing and Plate for Metaphyseal Fractures of the Distal Tibia

PURPOSE: To compare the radiological and clinical results between intramedullary nailing and plate fixation in the treatment of distal tibial fractures. MATERIALS AND METHODS: 19 cases of distal tibial metaphyseal fractures within 4 cm of the ankle joint line were enrolled. Ten patients were treated with interlocking intramedullary nail and the others with plate and screws. RESULTS: The mean union time was 14 weeks in nailing group and 16 weeks in plate group. The average angulation in AP view was 4.1 degrees in nailing group and 3.1 degrees in plate group. The average angulation in lateral view was 1.7 degrees in nailing group and 2.7 degrees in plate group. The rotational deformity was 2.8 degrees in nailing group and 1.7 degrees in plate group in average. There was no implant failure and soft tissue problem. CONCLUSION: There was no difference in clinical and radiological results between intramedullary nailing and plate in the treatment of the distal tibial fractures and, considering the preservation of the soft tissue, the intramedullary nails are a reliable method for managing distal metaphyseal fractures of the tibia.

Thoracolumbar Fracture with Posterior Ligament Complex Injury

PURPOSE: To evaluate the clinical features and radiographical landmarks of patients who has a thoracolumbar fracture combined with posterior ligament complex injury retrospectively. MATERIALS AND METHODS: The preoperative plain radiographys, axial CT, MRI and medical records of 27 patients were reviewed who were confirmed the posterior ligament complex injury in operation from January, 2002. to December, 2004. RESULTS: The patients were from 15 years to 75 years of age (mean 39.1 years), 20 males and 7 females. The mechanisms of injury were 17 falls from a height, 7 traffic accidents and 3 direct blow injuries. There were 17 cases (63%) in thoracolumbar transitional zone, such as 11 cases in T11-T12, 6 cases T12-L1. There were 9 cases of compression fracture and 18 cases of burst fracture according to the shape of fractured vertebra. In the plain radiograph, the degree of kyphotic angle was between 6~49 degrees (mean 22 degrees), anterior vertebral height loss was 7~70% (mean 39%), and posterior vertebral height loss was 0~8% (mean 3%). 21 cases (78%) were the anterior vertebral height loss below 50%, 23 cases (85%) were the degree of kyphotic angle below 30 degrees. Neurological deficits were not registered. 23 cases (85%) were positive in MRI and 24 cases (89%) were positive in direct focal tenderness in the view of posterior ligament complex injury. Conclusions: The posterior ligament complex injury is common finding of the thoracolumbar fracture. The high resolution MRI findings and direct focal tenderness are very importance in identifying the posterior ligament complex injury that is important prognostic factor particularly in mild anterior vertebral height loss and mild kyphotic angle in the plain radiograph.

Short Segment Fixation of Flexion-Distraction Injuries in Thoracolumbar Spines

PURPOSE: To evaluate the efficacy of short segment fixation in flexion-distraction injuries of thoracolumbar junction. MATERIALS AND METHODS: Twenty-five patients with a flexion-distraction injury in thoracolumbar junction confirmed by radiogram or MRI and stabilized with a short construct spanning short segment were included in this study. We investigated the location of fractures, type of fractures, anterior or posterior vertebral body height, and preoperative and postoperative kyphotic angle of injuried motion-segments on radiologic examinations and clinical outcome on the Oswestry score. RESULTS: A significant correction of deformity was achieved, from a mean preoperative kyphosis of 17.3 degrees to a mean postoperative kyphosis of 8.4 degrees. The loss of correction were minimal. The mean Oswestry score was 6.9, with 84% of patients having minimal disability (<20%) and no correlation with age, sex, the location of fractures, type of fractures, change of kyphotic angle. CONCLUSION: This study demonstrates the efficacy of posterior open reduction and short segment fixation of flexion-distraction injuries.

Treatment of Vertebral Pseudarthrosis after Compression Fracture

PURPOSE: To clarity the features of vertebral pseudarthrosis and to evaluate the efficacy of posterior instrumentation and fusion in treatment of it. MATERIALS AND METHODS: Twelve patients with severe back pain and intravertebral pseudarthrosis showing vacuum phenomenon were treated by in situ posterior instrumentation and fusion. The kyphotic angle of pre- and post-treatment was measured on a lateral radiograph. MRI was performed in all patients. The intravertebral instability was confirmed from the dynamic lateral view. The pain level was assessed both before and after the treatment using a visual analog scale. The kyphotic angle at last follow up was also checked. RESULTS: In eight cases, intravertebral instability was shown at the clefts in flexion-extension radiographs. MRI showed that the cleft was low intensity on the T1- weighted image and high intensity on the T2-weighted image. The pre-and postoperative mean kyphotic angles were -18.3degrees and -8.5degrees respectively. The preoperative average pain score was nine and postoperative four. At last follow up the mean kyphotic angle was -16.6degrees CONCLUSION: The cleft with intravertebral vacuum phenomenon and magnetic resonance findings of low intensity on the T1-weighted scans and high intensity on the T2-weighted scans suggests that the cleft is a pseudarthrosis associated with avascular necrosis of the vertebral body. The posterior instrumentation and fusion provides satisfactory pain relief in patient with vertebral pseudarthsosis.