Lumbar Interbody Fusion and Osteobiologics for Lumbar Fusion

Lumbar interbody fusion (LIF) is an excellent treatment option for a number of lumbar diseases. LIF can be performed through posterior, transforaminal, anterior, and lateral or oblique approaches. Each technique has its own pearls and pitfalls. Through LIF, segmental stabilization, neural decompression, and deformity correction can be achieved. Minimally invasive surgery has recently gained popularity and each LIF procedure can be performed using minimally invasive techniques to reduce surgery-related complications and improve early postoperative recovery. Despite advances in surgical technology, surgery-related complications after LIF, such as pseudoarthrosis, have not yet been overcome. Although autogenous iliac crest bone graft is the gold standard for spinal fusion, other bone substitutes are available to enhance fusion rate and reduce complications associated with bone harvest. This article reviews the surgical procedures and characteristics of each LIF and the osteobiologics utilized in LIF based on the available evidence.

Relationship between Sagittal Alignment and Anterior Bony Resorption of Cervical Vertebral Body in Patients with Ankylosing Spondylitis

Methods@#This retrospective study included 238 patients with AS who underwent surgical correction for thoracolumbar kyphosis. Of these, 80 patients with complete subaxial ankylosis were selected and divided into two groups: groups 1 (consisting of 28 patients with anterior bony resorption) and 2 (consisting of 52 patients without anterior resorption). Cervical sagittal parameters were analyzed and compared between the two groups. @*Results@#The average lateral diameter measured in patients with C5 anterior resorption was 84.2%±7.8% (62.4%–96.8%). Cervical lordosis was 8.7°±13.4° and 10.9°±11.5° in groups 1 and 2 (p=0.556), respectively. No significant differences were noted between the two groups on spinopelvic alignment in the T1 slope (52.2°±11.1° and 53.3°±9.9° in groups 1 and 2, respectively; p=0.742), C2–C7 sagittal vertical axis (SVA; 6.2±1.7 cm and 6.2±1.8 cm in groups 1 and 2, respectively; p=0.978), C7 SVA (14.3±4.9 cm and 14.6±6.2 cm in groups 1 and 2, respectively; p=0.823), or T1 pelvic angle (27.1°±8.9° and 31.6°±11.2° in groups 1 and 2, respectively; p=0.382). Correlation analyses were significant between the extent of anterior resorption and sagittal parameters, C2–C7 lordosis (R2=−0.428, p=0.021), and T1–T4 kyphosis (R2=−0.375, p=0.045). @*Conclusions@#Anterior bony resorption could develop by stress concentration. However, the development was not related to the sagittal alignment. The particular segments involved in developing anterior resorption varied, possibly because of their dependence on the preceding pattern of ankylosis.

Unstable Pathologic Vertebral Fractures in Multiple Myeloma : Propensity Score Matched Cohort Study between Reconstructive Surgery with Adjuvant Radiotherapy and Radiotherapy Alone

Objective@#: Although radiotherapy (RT) is recommended for multiple myeloma (MM) involving spine, the treatment of choice between reconstructive surgery with RT and RT alone for pathologic vertebral fractures (PVFs) associated with structural instability or neurologic compromises remains controversial. The purpose of this study was to evaluate the clinical efficacies of reconstructive surgery with adjuvant RT for treatment of MM with PVFs by comparing with matched cohorts treated with RT alone. @*Methods@#: Twenty-eight patients underwent reconstructive surgery followed by RT between 2008 and 2015 in a single institution, for management of PVFs associated with structural instability of the spine and/or neurologic compromises (group I). Twentyeight patients were treated with RT alone (group II) after propensity score matching in a 1-to-1 format based on instability of the spine, as well as age and performance. Clinical outcomes including the overall survival rates, duration of independent ambulation, neurological status, and numeric rating scale (NRS) for back pain were compared. @*Results@#: Clinical and radiological features before treatment were similar in both groups. The median survival period was similar between the two groups. However, the mean duration of independent ambulation was significantly longer in group I (88.8 months; 95% confidence interval [CI], 66.0–111.5) than in group II (39.4 months; 95% CI, 25.2–53.6) (log rank test; p=0.022). Deterioration of Frankel grade (21.4% vs. 60.7%, p=0.024) and NRS for back pain (2.7±2.2 vs. 5.0±2.7, p=0.000) at the last follow-up were higher in the group II. Treatment-related complications were similar in both groups. @*Conclusion@#: In patients with unstable PVFs due to MM, reconstructive surgery may yield superior clinical outcomes compared with RT alone in maintaining independent ambulation and neurological status, as well as pain control despite similar median survival and complications.

Analysis of Fracture Patterns and Characteristics in Sacral Insufficiency Fracture: Do Sacral Fractures Occur in Patients Who Had Previous Lumbosacral Fusion Insufficiency Fractures or Stress Fractures?

Methods@#In total, 55 patients with SIFs were retrospectively investigated in this study. The study population was divided into lumbosacral fusion (n=20) and non-fusion (n=35) groups. Subsequently, the patients’ demographic characteristics, comorbidities, medication history, results of diagnostic imaging studies, and bone mineral density were assessed. The fracture patterns were classified either according to the five typical types (H-pattern bilateral vertical plus horizontal component, unilateral vertical only, bilateral vertical only, unilateral vertical plus horizontal component, and horizontal only fracture) or atypical types. @*Results@#In total, 44 of 55 patients (80%) suffered from more than one senile disease and received corresponding medications that caused secondary osteoporosis. A total of 12 patients had S1 lumbosacral fixation. Moreover, three of these 12 patients who developed a SIF immediately after a lumbosacral fracture had an unstable sacral U fracture. The remaining nine patients showed fracture patterns similar to the non-fusion patients. Single-photon emission computed tomography (SPECT)/computed tomography (CT) can identify fracture recurrence in previously healed fractures. In total, 24 patients (43.6%) had fractures of the pelvis, femur, and thoracolumbar spine. @*Conclusions@#SIF develops in elderly patients with multiple adult diseases that can induce secondary osteoporosis. Such fractures may occur in the patients with instrumented lumbosacral fusion. Importantly, some patients showed stress fractures after multilevel instrumented lumbosacral fusion, whereas others showed insufficiency fractures. The different fracture patterns correspond to different grades of SIF, and SPECT/CT can easily identify the fracture status.

Decompressive Laminectomy Alone for Degenerative Lumbar Scoliosis with Spinal Stenosis: Incidence of Post-Laminectomy Instability in the Elderly

Background@#Decompressive laminectomy alone for degenerative lumbar scoliosis (DLS) is not recommended because it can lead to further instability. However, it is uncertain whether instability at the decompressed segments is directly affected by laminectomy or the natural progression of DLS. The purpose of this study was to evaluate the surgical outcome of decompressive laminectomy alone for DLS with spinal stenosis and to determine whether the procedure leads to post-laminectomy instability (PLI). @*Methods@#We retrospectively reviewed 60 patients with DLS. They were divided into 2 groups according to PLI criteria: stable group and PLI group. The PLI group was subdivided into 2 groups based on the level of PLI: the first group that showed PLI at the index laminectomy level (PLI-I) and the second group that showed PLI at another level other than the laminectomy level (PLI-NI). Radiological evaluation was performed to determine factors associated with the progression of DLS. Pain and disability outcomes were assessed. @*Results@#There were 34 patients (56.7%) in the stable group and 26 patients (43.3%) in the PLI group. Twelve patients (20.0%) underwent revision surgery. Eleven patients (18.3%) showed PLI at the index segments (PLI-I group), and 15 patients (25%) showed PLI at the adjacent or cephalad segments, not related to the laminectomy site (PLI-NI group). Four patients underwent revision surgery in the stable group and 8 in the PLI group. Survivorship analyses revealed that the predicted survivorship of DLS was 90.0% at 12 months and 86.4% at 24 months after laminectomy. @*Conclusions@#The development of PLI was not always related to laminectomy at the index level. However, PLI developed more rapidly at the index level, compared to the natural progression of the scoliotic curve at the adjacent segments.

Incidence and Risk Factors of Gastrointestinal and Hepatobiliary Complications after Spinal Fusion Surgery: a Retrospective Cohort Study

Background@#Spinal surgery holds a higher chance of unpredicted postoperative medical complications among orthopedic surgeries. Several studies have analyzed the risk factors for diverse postoperative medical complications, but the majority investigated incidences of each complication qualitatively. Among gastrointestinal complications, reports regarding postoperative ileus were relatively frequent. However, risk factors or incidences of hepatobiliary complications have yet to be investigated. The purpose of this study was to examine the incidence of gastrointestinal complications after spinal surgery, quantitatively analyze the risk factors of frequent complications, and to determine cues requiring early approaches. @*Methods@#In total, 234 consecutive patients who underwent spinal fusion surgery performed by one senior doctor at our institute in one-year period were retrospectively enrolled for analyses. The primary outcomes were presence of paralytic ileus, elevated serum alanine transaminase (ALT) and aspartate transaminase (AST) levels, and elevated total bilirubin levels. Univariate logistic regression analyses of all variables were performed. In turn, significant results were reanalyzed by multivariate logistic regression. The variables used were adjusted with age and gender. @*Results@#Gastrointestinal complications were observed in 15.8% of patients. Upon the risk factors of postoperative ileus, duration of anesthesia (odds ratio [OR], 1.373; P = 0.015), number of fused segments (OR, 1.202; P = 0.047), and hepatobiliary diseases (OR, 2.976; P = 0.029) were significantly different. For elevated liver enzymes, men (OR, 2.717; P = 0.003), number of fused segments (OR, 1.234; P = 0.033), and underlying hepatobiliary (OR, 2.704; P = 0.031) and rheumatoid diseases (OR, 5.021; P = 0.012) had significantly different results. Lastly, risk factors for total bilirubin elevation were: duration of anesthesia (OR, 1.431; P = 0.008), number of fused segments (OR, 1.359; P = 0.001), underlying hepatobiliary diseases (OR, 3.426; P = 0.014), and thoracolumbar junction involving fusions (OR, 4.134; P = 0.002) compared to lumbar spine limited fusions. @*Conclusion@#Patients on postoperative care after spinal surgery should receive direct attention as soon as possible after manifesting abdominal symptoms. Laboratory and radiologic results must be carefully reviewed, and early consultation to gastroenterologists or general surgeons is recommended to avoid preventable complications.

Lumbar Interbody Fusion: Techniques, Pearls and Pitfalls

Lumbar interbody fusion (LIF) is an effective and popular surgical procedure for the management of various spinal pathologies, especially degenerative diseases. Currently, LIF can be performed with posterior, transforaminal, anterior, and lateral approaches by open surgery or minimally invasive surgery (MIS). Each technique has its own advantages and disadvantages. In general, posterior LIF is a well-established procedure with good fusion rates and low complication rates but is limited by the possibility of iatrogenic injury to the neural structures and paraspinal muscles. Transforaminal LIF is frequently performed using an MIS technique and has an advantage of reducing these iatrogenic injuries. Anterior LIF (ALIF) can restore the disk height and sagittal alignment but has inherent approach-related challenges such as visceral and vascular complications. Lateral LIF and oblique LIF are performed using an MIS technique and have shown postoperative outcomes similar to ALIF; however, these approaches carry a risk of injury to psoas, lumbar plexus, and vascular structures. Herein, we provide a detailed description of the surgical procedures of each LIF technique. We shall then consider the pearls and pitfalls, as well as propose surgical indications and contraindications based on the available evidence in the literatures.

Surgical Extent of Metastatic Spine Tumor Excision and Its Effects on Postoperative Ambulatory Function: Comparison of Extensive Wide versus Palliative Excision Surgery

OBJECTIVES@#To compare surgical outcomes such as the ambulatory period and survival according to different surgical excision tactics for metastatic spine tumors (MSTs).SUMMARY OF LITERATURE REVIEW: Surgical outcomes, such as pain relief and survival, in patients with MSTs have been reported in several studies, but the effects of differences in surgical extent on the ambulatory period have rarely been reported.@*MATERIALS AND METHODS@#Ninety-six patients with MSTs who underwent palliative (n=60) or extensive wide excision (n=36) were included. Palliative excision was defined as partial removal of the tumor as an intralesional piecemeal procedure for decompression. Extensive wide excision was defined as a surgical attempt to remove the whole tumor at the index level as completely as possible. The primary outcome was the ambulatory period following surgery. Other demographic and radiographic parameters were analyzed to identify the risk factors for loss of ambulatory ability and survival. Perioperative complications were also assessed.@*RESULTS@#The mean postoperative ambulatory period was longer in the extensive wide excision group (average 14.8 months) than in the palliative excision group (average 11.7 months) (p=0.021). The survival rates were not significantly different between the two surgical excision groups (p=0.680). However, postoperative ambulatory status and major complications within 30 days postoperatively were significant prognostic factors for survival (p=0.003 and p=0.032, respectively).@*CONCLUSIONS@#The extent of surgical excision affected the ambulatory period, and the complication rates were similar, regardless of surgical excision tactics. A proper surgical strategy to achieve postoperative ambulatory ability and to reduce perioperative complications would have a favorable effect on survival.

Prevalence of Thoracic Scoliosis in Koreans Using Simple Chest Radiography

OBJECTIVES@#To provide reference data for the study and treatment of thoracic scoliosis.SUMMARY OF LITERATURE REVIEW: There have been no reports on the prevalence of thoracic scoliosis in Korea.@*MATERIALS AND METHODS@#From August 2011 to October 2012, radiographs of patients under 80 years of age who underwent routine chest radiographs were retrospectively reviewed. Based on their age when the chest radiographs were obtained, the patients were divided into 8 groups. The prevalence and angle of the curve of thoracic scoliosis were investigated in each age group, and the prevalence of thoracic scoliosis according to sex, the direction of the curve, number of vertebrae in the major curve, the location and rotation of the apical vertebrae, and osteophyte location were examined.@*RESULTS@#The prevalence of thoracic scoliosis was 2.4% (621 patients), and female patients (3.0%, 375 of 12471) showed a higher prevalence than male patients (1.8%, 246 of 13654) (p<0.001). Right curvature was present in 445 patients and left curvature in 176 patients. In each age group, the prevalence and degree of thoracic scoliosis were 1.1% (14.2°±3.2°), 2.3% (17.4°±7.7°), 2.5% (17.0°±8.9°), 1.9% (15.8°±5.9°), 1.3% (15.5°±6.6°), 2.1% (18.0°±13.6°), 2.9% (14.3°±3.6°), and 6.1% (16.2°±4.8°), respectively. The mean curvature in all scoliosis patients was 16.0°±7.0°. The angle of the curve was significantly different by sex (15.4°±7.1° for males, 16.8°±7.6° for females). The average curve angle of patients with thoracic scoliosis was 16.0°±7.0°, among whom it was 10°–20° in 533 patients, 20°–30° in 64, 30°–40° in 11, and over 40° in 13.@*CONCLUSIONS@#This study could be used as a reference point for the study and treatment of thoracic scoliosis.

Clinical Characteristics and Outcomes of Patients with Culture-Negative Pyogenic Spondylitis according to Empiric Glycopeptide Use

BACKGROUND@#The optimal choice of antibiotics is challenging in culture-negative pyogenic spondylitis (PS). The empiric use of glycopeptides is suggested depending on various risk factors, although clinical data are sparse. This study aimed to analyze the clinical characteristics and outcomes of patients with culture-negative PS and evaluate the effect of empiric glycopeptide use on clinical outcomes in these patients.@*MATERIALS AND METHODS@#Data on the characteristics, treatment, and outcomes of 175 patients diagnosed with PS were retrospectively obtained from the electronic database of a tertiary referral hospital from 2009 to 2016. Patients with negative culture results were grouped by the duration of glycopeptide treatment: glycopeptide therapy <28 days (Group A) and glycopeptide therapy ≥28 days (Group B).@*RESULTS@#Of 89 patients with negative culture results, 78 were included in the analysis (Group A, n = 66; Group B, n = 12). The mean age of patients with negative culture results was 65.5 years, and 52.6% were male. The median follow-up duration was 573 (interquartile range [IQR], 83 – 1,037) days. The duration of intravenous glycopeptide therapy was 0.0 (IQR, 0.0 – 0.0) days and 55.5 (IQR, 37.0 – 75.7) days for Groups A and B, respectively. Patients who used glycopeptide longer empirically (Group B) had more commonly undergone a previous spinal procedure, including surgery (P = 0.024). The length of hospitalization, erythrocyte sedimentation rate, and C-reactive protein level were significantly higher in Group B compared with those in Group A (P <0.001, P <0.001, and P = 0.006, respectively). Regarding treatment modalities, patients in Group B underwent surgery more frequently (P = 0.017). The duration of parenteral antibiotic treatment was longer in Group B (P <0.001). Recurrence was noted in 7 patients (9.0%), and the recurrence rate was not significantly different between the 2 groups (Group A, 5/66 [7.6%]; Group B, 2/12 [16.7%]; P = 0.293).@*CONCLUSION@#The recurrence rate among patients with culture-negative PS was not different based on the duration of empiric glycopeptide use. However, considering the small sample size and heterogeneity of our study population, we suggest that it is reasonable to administer glycopeptide antibiotics in these patients depending on clinical risk factors. Further large-scale prospective studies are needed to obtain more evidence for appropriate antibiotic treatment.

Clinical Significance of Preoperative Embolization for Non-Hypervascular Metastatic Spine Tumors

OBJECTIVE: The efficacy of preoperative embolization for hypervascular metastatic spine disease (MSD) such as renal cell and thyroid cancers has been reported. However, the debate on the efficacy of preoperative embolization for non-hypervascular MSD still remains unsettled. The purpose of this study is to determine whether preoperative embolization for non-hypervascular MSD decreases perioperative blood loss.METHODS: A total of 79 patients (36 cases of preoperative embolization and 43 cases of non-embolization) who underwent surgery for metastatic spine lesions were included. Representative hypervascular tumors such as renal cell and thyroid cancers were excluded. Intraoperative and perioperative estimated blood losses (EBL), total number of transfusion and calibrated EBL were recorded in the embolization and non-embolization groups. The differences in EBL were also compared along with the type of surgery. In addition, the incidence of Adamkiewicz artery and complications of embolization were assessed.RESULTS: The average age of 50 males and 29 females was 57.6±13.5 years. Lung (30), hepatocellular (14), gastrointestinal (nine) and others (26) were the primary cancers. The demographic data was not significantly different between the embolization and the non-embolization groups. There were no significant differences in intraoperative EBL, perioperative EBL, total transfusion and calibrated EBL between two groups. However, intraoperative EBL and total transfusion in patients with preoperative embolization were significantly lower than in non-embolization in the corpectomy group (1645.5 vs. 892.6 mL, p=0.017 for intraoperative EBL and 6.1 vs. 3.9, p=0.018 for number of transfusion). In addition, the presence of Adamkiewicz artery at the index level was noted in two patients. Disruption of this major feeder artery resulted in significant changes in intraoperative neuromonitoring.CONCLUSION: Preoperative embolization for non-hypervascular MSD did not reduce perioperative blood loss. However, the embolization significantly reduced intraoperative bleeding and total transfusion in corpectomy group. Moreover, the procedure provided insights into the anatomy of tumor and spinal cord vasculature.

Clinical Significance of Preoperative Embolization for Non-Hypervascular Metastatic Spine Tumors

OBJECTIVE: The efficacy of preoperative embolization for hypervascular metastatic spine disease (MSD) such as renal cell and thyroid cancers has been reported. However, the debate on the efficacy of preoperative embolization for non-hypervascular MSD still remains unsettled. The purpose of this study is to determine whether preoperative embolization for non-hypervascular MSD decreases perioperative blood loss. METHODS: A total of 79 patients (36 cases of preoperative embolization and 43 cases of non-embolization) who underwent surgery for metastatic spine lesions were included. Representative hypervascular tumors such as renal cell and thyroid cancers were excluded. Intraoperative and perioperative estimated blood losses (EBL), total number of transfusion and calibrated EBL were recorded in the embolization and non-embolization groups. The differences in EBL were also compared along with the type of surgery. In addition, the incidence of Adamkiewicz artery and complications of embolization were assessed. RESULTS: The average age of 50 males and 29 females was 57.6±13.5 years. Lung (30), hepatocellular (14), gastrointestinal (nine) and others (26) were the primary cancers. The demographic data was not significantly different between the embolization and the non-embolization groups. There were no significant differences in intraoperative EBL, perioperative EBL, total transfusion and calibrated EBL between two groups. However, intraoperative EBL and total transfusion in patients with preoperative embolization were significantly lower than in non-embolization in the corpectomy group (1645.5 vs. 892.6 mL, p=0.017 for intraoperative EBL and 6.1 vs. 3.9, p=0.018 for number of transfusion). In addition, the presence of Adamkiewicz artery at the index level was noted in two patients. Disruption of this major feeder artery resulted in significant changes in intraoperative neuromonitoring. CONCLUSION: Preoperative embolization for non-hypervascular MSD did not reduce perioperative blood loss. However, the embolization significantly reduced intraoperative bleeding and total transfusion in corpectomy group. Moreover, the procedure provided insights into the anatomy of tumor and spinal cord vasculature.

Surgical Extent of Metastatic Spine Tumor Excision and Its Effects on Postoperative Ambulatory Function: Comparison of Extensive Wide versus Palliative Excision Surgery / 대한척추외과학회지

STUDY DESIGN: Retrospective study. OBJECTIVES: To compare surgical outcomes such as the ambulatory period and survival according to different surgical excision tactics for metastatic spine tumors (MSTs). SUMMARY OF LITERATURE REVIEW: Surgical outcomes, such as pain relief and survival, in patients with MSTs have been reported in several studies, but the effects of differences in surgical extent on the ambulatory period have rarely been reported. MATERIALS AND METHODS: Ninety-six patients with MSTs who underwent palliative (n=60) or extensive wide excision (n=36) were included. Palliative excision was defined as partial removal of the tumor as an intralesional piecemeal procedure for decompression. Extensive wide excision was defined as a surgical attempt to remove the whole tumor at the index level as completely as possible. The primary outcome was the ambulatory period following surgery. Other demographic and radiographic parameters were analyzed to identify the risk factors for loss of ambulatory ability and survival. Perioperative complications were also assessed. RESULTS: The mean postoperative ambulatory period was longer in the extensive wide excision group (average 14.8 months) than in the palliative excision group (average 11.7 months) (p=0.021). The survival rates were not significantly different between the two surgical excision groups (p=0.680). However, postoperative ambulatory status and major complications within 30 days postoperatively were significant prognostic factors for survival (p=0.003 and p=0.032, respectively). CONCLUSIONS: The extent of surgical excision affected the ambulatory period, and the complication rates were similar, regardless of surgical excision tactics. A proper surgical strategy to achieve postoperative ambulatory ability and to reduce perioperative complications would have a favorable effect on survival.

Prevalence of Thoracic Scoliosis in Koreans Using Simple Chest Radiography / 대한척추외과학회지

STUDY DESIGN: A cross-sectional study. OBJECTIVES: To provide reference data for the study and treatment of thoracic scoliosis. SUMMARY OF LITERATURE REVIEW: There have been no reports on the prevalence of thoracic scoliosis in Korea. MATERIALS AND METHODS: From August 2011 to October 2012, radiographs of patients under 80 years of age who underwent routine chest radiographs were retrospectively reviewed. Based on their age when the chest radiographs were obtained, the patients were divided into 8 groups. The prevalence and angle of the curve of thoracic scoliosis were investigated in each age group, and the prevalence of thoracic scoliosis according to sex, the direction of the curve, number of vertebrae in the major curve, the location and rotation of the apical vertebrae, and osteophyte location were examined. RESULTS: The prevalence of thoracic scoliosis was 2.4% (621 patients), and female patients (3.0%, 375 of 12471) showed a higher prevalence than male patients (1.8%, 246 of 13654) (p<0.001). Right curvature was present in 445 patients and left curvature in 176 patients. In each age group, the prevalence and degree of thoracic scoliosis were 1.1% (14.2°±3.2°), 2.3% (17.4°±7.7°), 2.5% (17.0°±8.9°), 1.9% (15.8°±5.9°), 1.3% (15.5°±6.6°), 2.1% (18.0°±13.6°), 2.9% (14.3°±3.6°), and 6.1% (16.2°±4.8°), respectively. The mean curvature in all scoliosis patients was 16.0°±7.0°. The angle of the curve was significantly different by sex (15.4°±7.1° for males, 16.8°±7.6° for females). The average curve angle of patients with thoracic scoliosis was 16.0°±7.0°, among whom it was 10°–20° in 533 patients, 20°–30° in 64, 30°–40° in 11, and over 40° in 13. CONCLUSIONS: This study could be used as a reference point for the study and treatment of thoracic scoliosis.

Bone Mineral Density and Osteoporotic Vertebral Fractures in Traditional, Unassisted, Free-Diving Women (Haenyeos)

BACKGROUND: Water pressure and muscle contraction may influence bone mineral density (BMD) in a positive way. However, divers experience weightlessness, which has a negative effect on BMD. The present study investigated BMD difference in normal controls and woman free-divers with vertebral fracture and with no fracture. METHODS: Between January 2010 and December 2014, traditional woman divers (known as Haenyeo in Korean), and non-diving women were investigated. The study population was divided into osteoporotic vertebral fracture and non-fracture groups. The BMD of the lumbar spine and femoral neck was measured. The radiological parameters for global spinal sagittal balance were measured. RESULTS: Thirty free-diving women and thirty-three non-diving women were enrolled in this study. The mean age of the divers was 72.1 ± 4.7 years and that of the controls was 72.7 ± 4.0 years (P = 0.61). There was no statistical difference in BMD between the divers and controls. In divers, cervical lordosis and pelvic tilt were significantly increased in the fracture subgroup compared to the non-fracture subgroup (P = 0.028 and P = 0.008, respectively). Sagittal vertical axis was statistically significantly correlated with cervical lordosis (Spearman's rho R = 0.41, P = 0.03), and pelvic tilt (Spearman's rho R = 0.46, P = 0.01) in divers. CONCLUSION: BMD did not differ significantly between divers and controls during their postmenopausal period. When osteoporotic spinal fractures develop, compensation mechanisms, such as increased cervical lordosis and pelvic tilt, was more evident in traditional woman divers. This may be due to the superior back muscle strength and spinal mobility of this group of women.

Diagnosis of Nerve Root Compromise of the Lumbar Spine: Evaluation of the Performance of Three-dimensional Isotropic T2-weighted Turbo Spin-Echo SPACE Sequence at 3T

OBJECTIVE: To explore the performance of three-dimensional (3D) isotropic T2-weighted turbo spin-echo (TSE) sampling perfection with application optimized contrasts using different flip angle evolution (SPACE) sequence on a 3T system, for the evaluation of nerve root compromise by disc herniation or stenosis from central to extraforaminal location of the lumbar spine, when used alone or in combination with conventional two-dimensional (2D) TSE sequence. MATERIALS AND METHODS: Thirty-seven patients who had undergone 3T spine MRI including 2D and 3D sequences, and had subsequent spine surgery for nerve root compromise at a total of 39 nerve levels, were analyzed. A total of 78 nerve roots (48 symptomatic and 30 asymptomatic sites) were graded (0 to 3) using different MRI sets of 2D, 3D (axial plus sagittal), 3D (all planes), and combination of 2D and 3D sequences, with respect to the nerve root compromise caused by posterior disc herniations, lateral recess stenoses, neural foraminal stenoses, or extraforaminal disc herniations; grading was done independently by two readers. Diagnostic performance was compared between different imaging sets using the receiver operating characteristics (ROC) curve analysis. RESULTS: There were no statistically significant differences (p = 0.203 to > 0.999) in the ROC curve area between the imaging sets for both readers 1 and 2, except for combined 2D and 3D (0.843) vs. 2D (0.802) for reader 1 (p = 0.035), and combined 2D and 3D (0.820) vs. 3D including all planes (0.765) for reader 2 (p = 0.049). CONCLUSION: The performance of 3D isotropic T2-weighted TSE sequence of the lumbar spine, whether axial plus sagittal images, or all planes of images, was not significantly different from that of 2D TSE sequences, for the evaluation of nerve root compromise of the lumbar spine. Combining 2D and 3D might possibly improve the diagnostic accuracy compared with either one.

Surfer's Myelopathy: A Case Report

STUDY DESIGN: A case report. OBJECTIVES: To report a rare cause of non-traumatic spinal cord injury (SCI) during surfing SUMMARY OF LITERATURE REVIEW: Surfer's myelopathy is a non-traumatic SCI associated with the hyperextension posture during paddling in surfing. Although the definite pathomechanism has not been identified, cord ischemia followed by arterial infarction may be related to this injury. MATERIALS AND METHODS: A young healthy male patient presented with a SCI that occurred during his first time surfing. Magnetic resonance imaging revealed a T2-hyperintense lesion in the spinal cord from D10 to the conus medullaris. RESULTS: The patient completely recovered without any neurologic deficits after steroid therapy and other forms of supportive management. CONCLUSIONS: Since surfing is becoming more common in Korea, awareness of surfer's myelopathy is important for early diagnosis and proper management.

Spinal Cord Injury and Related Clinical Trials

Spinal cord injury (SCI) has been considered an incurable condition and it often causes devastating sequelae. In terms of the pathophysiology of SCI, reducing secondary damage is the key to its treatment. Various researches and clinical trials have been performed, and some of them showed promising results; however, there is still no gold standard treatment with sufficient evidence. Two therapeutic concepts for SCI are neuroprotective and neuroregenerative strategies. The neuroprotective strategy modulates the pathomechanism of SCI. The purpose of neuroprotective treatment is to minimize secondary damage following direct injury. The aim of neuroregenerative treatment is to enhance the endogenous regeneration process and to alter the intrinsic barrier. With advancement in biotechnology, cell therapy using cell transplantation is currently under investigation. This review discusses the pathophysiology of SCI and introduces the therapeutic candidates that have been developed so far.

Surgical Roles for Spinal Involvement of Hematological Malignancies

OBJECTIVE: Patients with hematological malignancies frequently encounter spine-related symptoms, which are caused by disease itself or process of treatment. However, there is still lack of knowledge on their epidemiology and clinical courses. The purpose of this article is to review clinical presentations and surgical results for spinal involvement of hematologic malignancies. METHODS: From January 2011 to September 2014, 195 patients (98 males and 97 females) suffering from hematological malignancies combined with spinal problems were retrospectively analyzed for clinical and radiological characteristics and their clinical results. RESULTS: The most common diagnosis of hematological malignancy was multiple myeloma (96 patients, 49.7%), followed by chronic myeloid leukemia (30, 15.2%), acute myeloid leukemia (22, 11.2%), and lymphoma (15, 7.56%). The major presenting symptoms were mechanical axial pain (132, 67.7%) resulting from pathologic fractures, and followed by radiating pain (49, 25.1%). Progressive neurologic deficits were noted in 15 patients (7.7%), which revealed as cord compression by epidural mass or compressive myelopathy combined with pathologic fractures. Reconstructive surgery for neurologic compromise was done in 16 patients. Even though surgical intervention was useful for early paralysis (Frankel grade D or E), neurologic recovery was not satisfactory for the progressed paralysis (Frankel grade A or B). CONCLUSION: Hematological malignancies may cause various spinal problems related to disease progression or consequences of treatments. Conservative and palliative treatments are mainstay for these lesions. However, timely surgical interventions should be considered for the cases of pathologic fractures with progressive neurologic compromise.

Transplantation of Mesenchymal Stem Cells for Acute Spinal Cord Injury in Rats: Comparative Study between Intralesional Injection and Scaffold Based Transplantation

Experimental stem cell therapy for spinal cord injury (SCI) has been extensively investigated. The selection of effective cell transplantation route is also an important issue. Although various types of scaffold have been widely tried as a carrier of stem cells to the injured spinal cord, there was little comparative study to investigate the efficacy of transplantation comparing with conventional transplantation route. A total of 48 Sprague-Dawley rats were subjected to standardized SCI, followed by transplantation of allogeneic mesenchymal stem cells (MSCs), either via intralesional injection (IL group), or via the poly (lactic-co-glycolic acid) (PLGA) scaffold (IP group) or chitosan scaffold (IC group). Engraftment and differentiation of the transplanted cells, expression of neurotrophic factors in the injured spinal cord, and functional recovery were compared with those of the control group. The mean numbers of engrafted MSCs in the IL, IP, and IC groups were 20.6 ± 0.7, 25.6 ± 1.7 and 26.7 ± 1.8 cells/high power filed (HPF), respectively. Results showed higher success rate of MSCs engraftment in the scaffold groups compared to the IL group. Expression of neuroprotective growth factors in the SCI lesions showed no significant differences between the IL, IP, and IC groups. The mean Basso, Beattie and Bresnahan locomotor scales at 6 weeks post-transplantation in the IL, IP, IC, and control groups were 7.9 ± 1.1, 7.9 ± 2.1, 8.7 ± 2.1, and 2.9 ± 1.0, respectively. The functional improvement was most excellent in the IC group. The scaffold based MSC transplantation for acute SCI presented the better cell engraftment and neuroprotective effect compared to the intralesional injection transplantation.