Intradural extramedullary spinal choristoma: A case report.

RATIONALE: A choristoma is a rare and benign neoplasm characterized by the presence of normal tissue in an anomalous anatomical location. In contrast, choristoma tend to occur in other body regions rather than within the spinal canal. Before our findings, only 4 cases of intraspinal choristoma had been recorded. Because its composition is complex and very rare, routine examinations, such as magnetic resonance imaging, are difficult to diagnose, and the possibility of its occurrence is often missed in clinical diagnosis. If there is no specificity in its components, such as in this case, even pathological examinations can only confirm the diagnosis as choristoma after eliminating other possibilities. Therefore, in clinical practice, when encountering patients with intraspinal tumors, it is essential to consider the possibility of choristoma. In this case, the choristoma lack of specific constituent composition sets it apart from previously reported intraspinal choristoma, significantly raising the diagnostic challenge, which offers valuable insights for clinical diagnosis. PATIENT CONCERNS: A female patient aged 48 years was admitted to our medical center due to experiencing persistent lower back pain accompanied by radiating pain in both legs for 5 months. Based on the findings from the neurological physical examination and magnetic resonance imaging, the patient was diagnosed with an intradural space-occupying lesion located at the level of the first lumbar vertebral body. We performed an enhanced magnetic resonance neurography examination to further determine the positional relationship between the occupation and nerves in preparation for surgery. Postoperative pathological biopsy showed that the mass was an intraspinal choristoma. DIAGNOSIS: Intradural extramedullary spinal choristoma. INTERVENTION: Occupied lesion is removed surgically. OUTCOMES: After surgery, all symptoms were significantly relieved, and when the patient was discharged, all symptoms disappeared completely. There was no sign of recurrence after 1 year of follow-up. LESSONS: Intraspinal choristomas are not specific and need to be diagnosed by pathologic examination. Early detection of and intervention for intraspinal tumors can mitigate nerve dysfunction.

Late presentation of dural tears: Two case reports and review of literature.

BACKGROUND: The late presentation of dural tears (LPDT) has a low incidence rate and hidden symptoms and is easily ignored in clinical practice. If the disease is not treated in time, a series of complications may occur, including low intracranial pressure headache, infection, pseudodural cyst formation, and sinus formation. Here, we describe two cases of LPDT. CASE SUMMARY: Two patients had sudden fever 1 wk after lumbar surgery. Physical examination showed obvious tenderness in the operation area. The patients were confirmed as having LPDT by lumbar magnetic resonance imaging and surgical exploration. One case was caused by continuous negative pressure suction and malnutrition, and the other was caused by decreased dural ductility and low postoperative nutritional status. The first symptom of both patients was fever, with occasional headache. Both patients underwent secondary surgery to treat the LPDT. Dural defects were observed and dural sealants were used to seal the dural defects, then drainage tubes were retained for drainage. After the operation, the patients were treated with antibiotics and the patients' surgical incisions healed well, without fever or incision tenderness. Both recovered and were discharged 1 wk after the operation. CONCLUSION: LPDT is a rare complication of spinal surgery or neurosurgery that has hidden symptoms and can easily be overlooked. Since it may cause a series of complications, LPDT needs to be actively addressed in clinical practice.

Clinical management of dural defects: A review.

Dural defects are common in spinal and cranial neurosurgery. A series of complications, such as cerebrospinal fluid leakage, occur after rupture of the dura. Therefore, treatment strategies are necessary to reduce or avoid complications. This review comprehensively summarizes the common causes, risk factors, clinical complications, and repair methods of dural defects. The latest research progress on dural repair methods and materials is summarized, including direct sutures, grafts, biomaterials, non-biomaterial materials, and composites formed by different materials. The characteristics and efficacy of these dural substitutes are reviewed, and these materials and methods are systematically evaluated. Finally, the best methods for dural repair and the challenges and future prospects of new dural repair materials are discussed.

A comparison of long-term efficacy of K-rod-assisted non-fusion operation and posterior lumbar interbody fusion for single-segmental lumbar disc herniation.

K-rod-assisted non-fusion surgery for the treatment of lumbar disc herniation has been proven to have short-term clinical efficacy. Meanwhile, its long-term effects have not been examined. To observed the long-term clinical efficacy of K-rod-assisted non-fusion operation, this study retrospectively analyzed 22 patients with lumbar disc (L4/5) herniation who underwent K-rod-assisted non-fusion operation (n = 13) or PLIF (n = 9). They were followed-up for more than 5 years. The operation times and blood loss were significantly reduced in the K-rod group compared to the PLIF group. At the last follow-up, the clinical outcomes of the K-rod group were improved compared to those of the PLIF group as observed by the VAS score, JOABPEQ, and ODI. Imaging outcomes at the last follow-up indicated that the loss of height in the L3/4 and L5/S1 intervertebral space, the ROM of L3/4 and L5/S1, and the incidence of adjacent segment degeneration in the PLIF group were significantly higher than those in the K-rod group. According to Pfirrmann grading, Modic changes, and UCLA grading, the incidence of adjacent segment degeneration was 55.6% in the PLIF group and 15.4% in the K-rod group. Changes in spino-pelvic parameters between the two groups were as follows: pelvic index remained unchanged, pelvic tilt angle increased, and lumbar lordosis and sacral slope decreased. Therefore, compared to PLIF, single-segment lumbar disc herniation using K-rod-assisted non-fusion surgery resulted in better long-term clinical efficacy. Our results demonstrate that this procedure can delay adjacent segment degeneration after lumbar surgery.

Spinal dural arteriovenous fistula 8 years after lumbar discectomy surgery: A case report and review of literature.

BACKGROUND: Spinal dural arteriovenous fistula (SDAVF) is an extremely rare vascular malformation of the central nervous system that is often confused with degenerative spinal disorders due to similar early symptoms and clinical features. Here, we report a case of SDAVF recurrence 8 years after lumbar spine surgery and summarize relevant literature. CASE SUMMARY: A 54-year-old male was admitted to our hospital complaining of lower back pain, numbness in both lower extremities and intermittent claudication. Subsequent imaging identified lumbar spinal stenosis. Following surgical treatment, the patient's symptoms significantly resolved, and he was able to perform daily activities. However, similar symptoms appeared 8 years later, followed by confirmation of SDAVF diagnosis. The patient underwent neurosurgery 7 mo after symptom onset. The follow-up period lasted 14 mo, and the patient remains with marginal neurological symptoms. CONCLUSION: This case highlights the importance of prompt SDAVF diagnosis. Due to its nonspecific clinical presentation, the clinical experience of the surgeon and definitive imaging examination are indispensable. Additionally, timely neurosurgery is effective and may significantly improve patient outcomes.

A screw view model of navigation guided minimal invasive percutaneous pelvic screws insertion for lateral compression pelvic ring injuries: A case report.

RATIONALE: The objective of the present study was to evaluate the accuracy, effectiveness, and safety of screw view model of navigation (SVMN) guided minimal invasive percutaneous pelvic screws (PPSs) insertion for lateral compression pelvic ring injuries (PRI). PATIENT CONCERNS: A female patient experienced a high falling injury, and presented with pain, swelling, deformity, and movement limitation of the left hip for 3 hours. DIAGNOSES: She was diagnosed with pelvic fractures, left iliac fracture, left pubic branch fracture, left ischial branch fracture, and lumbar transverse process fracture. INTERVENTIONS: We used a SVMN technique to guide PPSs insertion, including a percutaneous anterior inferior iliac spine screw, a percutaneous iliac screw (PIS), and a percutaneous sacroiliac screw (PSIS). OUTCOMES: In total, 3 PPSs were inserted and all were presented with excellent position postoperatively. The designing time of all screws was 11.7 minutes, the time of all guide needles insertion was 18.1 minutes, the time of all screws insertion was 32.8 minutes, blood loss was 21 mL, and the time of radiation exposure lasted 7.2 minutes. Moreover, surgical complications, including neurovascular compromise, wound infection, fracture nonunion, and screw loosening, were not observed during the 12 months follow up visit. LESSONS: SVMN technique guided PPSs insertion is an effective and safety approach for the treatment of PRI in selected patients. Besides, it is necessary for surgeons to master the rationale of computer navigation, to familiar with the anatomy of pelvis and to select suitable patients.

A novel computer navigation model guided unilateral percutaneous vertebroplasty for vertebral compression fracture: A case report.

RATIONAL: Vertebral compression fracture (VCF) is one of the most common diseases in spinal surgery. Traditional percutaneous vertebroplasty (PVP) under fluoroscopy is an effective method to treat vertebral compression fracture. However, there is still a risk of vascular nerve injury and infection caused by inaccurate or repeated puncture. Therefore, the purpose of this paper was to assess the accuracy of unilateral PVP guided by screw view model of navigation (SVMN) for VCF. PATIENT CONCERNS: A 59-year-old female patient suffered high falling injury, and with back pain as its main clinical symptom. DIAGNOSES: The patient was diagnosed with a L1 VCF. INTERVENTIONS: We placed the puncture needle under the guidance of SVMN to reach the ideal position designed before operation, and then injected the bone cement to complete the percutaneous kyphoplasty (PKP). OUTCOMES: The operative time was 29.5 minutes, the puncture time was 1 time, the fluoroscopy time was 2.9 minutes, and the bone cement distribution was satisfactory. VAS and ODI scores were significant improved postoperatively. No surgical complications, including neurovascular injury and infection, were observed during 28-month follow up. LESSONS: The SVMN guided percutaneous puncture needle insertion in PKP operation for VCF is an effective and safety technique. Besides, the SVMN has also been a contributor to reduce radiation doses and replace conventional fluoroscopy.

Combined 3-dimensional printing model and 3-dimensional fluoroscopic navigation to assist C2 pedicle screw insertion: A case report.

RATIONALE: The misplaced cervical screw can cause catastrophic surgical complications, such as nerve root damage, vertebral artery compromise, spinal cord injury, and even paraplegia. Thus, the present study aims to describe a novel technique of 3-dimensional printing model (3DPM) combined with 3-dimensional fluoroscopic navigation (3DFN) to facilitate C2 pedicle screw insertion. PATIENT CONCERNS: A 56-year-old male patient presented hypoesthesia of the trunk and extremities, accompanied by a walking disorder. DIAGNOSES: Congenital atlantoaxial malformation with atlantoaxial dislocation. INTERVENTIONS: He underwent an occipital cervical fusion. We used 3DPM and 3DFN technology to guide C2 pedicle screws insertion. OUTCOMES: We inserted 2 pedicle screws and 4 lateral mass screws using the combined 3DPM and 3DFN technology. All screws were classified as excellent position postoperatively. The surgical duration, total fluoroscopic time, and the bleeding volume were 258 minutes, 3.9 minutes, and 237 mL, respectively. No surgical complications, such as neurological compromise, nonunion, dysphagia, infection, polypnea, fixation failure, pseudarthrosis formation, or revision surgery, were observed. The follow-up duration lasted 30 months. LESSONS: The combination of 3DPM and 3DFN to promote C2 pedicle screws implantation is a safe, accurate, reliable, and useful technology, which can achieve an excellent therapeutic effect and avoid surgical complications. However, using the 3DPM and 3DFN technology may increase the financial burden of patients.

Computer navigation-assisted minimally invasive percutaneous screw placement for pelvic fractures.

Pelvic fractures are often caused by high-energy injuries and accompanied by hemodynamic instability. Traditional open surgery has a large amount of bleeding, which is not suitable for patients with acute pelvic fracture. Navigation-guided, percutaneous puncture-screw implantation has gradually become a preferred procedure due to its advantages, which include less trauma, faster recovery times, and less bleeding. However, due to the complexity of pelvic anatomy, doctors often encounter some problems when using navigation to treat pelvic fractures. This article reviews the indications, contraindications, surgical procedures, and related complications of this procedure for the treatment of sacral fractures, sacroiliac joint injuries, pelvic ring injuries, and acetabular fractures. We also analyze the causes of inaccurate screw placement. Percutaneous screw placement under navigational guidance has the advantages of high accuracy, low incidence of complications and small soft-tissue damage, minimal blood loss, short hospital stays, and quick recovery. There is no difference in the incidence of complications between surgeries performed by new doctors and experienced ones. However, computer navigation technology requires extensive training, and attention should be given to avoid complications such as screw misplacement, intestinal injury, and serious blood vessel and nerve injuries caused by navigational drift.

Technology of percutaneous cannulated screw implantation using screw view model of navigation in Garden type I of femoral neck fracture: A case report.

RATIONALE: The aim of the present study was to assess the efficacy and safety of percutaneous cannulated screw (PCS) implantation assisted by screw view model of navigation (SVMN) to treat femoral neck fracture (FNF). PATIENT CONCERNS: A 42-year-old male patient suffered from a high falling injury, causing pain, swelling, deformity, and limited mobility on his right hip. DIAGNOSES: He was diagnosed with Garden type I of FNF. INTERVENTIONS: PCS implantation assisted by SVMN was used to treat fracture of femoral neck in this patient. OUTCOMES: The follow up lasted for 48 months. A total of 3 screws were inserted into femoral neck, all exhibiting excellent position. The mean screw deviation was 0.43° and 5.73° of femoral neck-shaft and anteversion angle, respectively. The guide wire drilling attempt of each screw was one-time. The fluoroscopic time lasted 6.3 minutes, the Harris hip scores improved from 67 to 88, and the blood loss was 35 mL. It took 11.7 minutes for designing the screws, 13.9 minutes for implanting the guide wires, and 37.3 minutes for placing the screws. No clinical complications were found during 48-month follow-up visit, including head penetration, implant failure, fracture nonunion, and femoral head osteonecrosis. LESSONS: The study revealed that SVMN is conducive to the PCS insertion for FNF. Our lesson is that the FNF must be well reduction before SVMN assisted PCS placement.

Combined navigated drilling and arthroscopy facilitate minimally invasive surgical treatment of ulnar-radial joint dislocation caused by epiphyseal premature closure: A case report.

RATIONALE: In this paper, the efficacy and safety of using navigated drilling and arthroscopy (NDA) to assist surgery for ulnar-radial joint dislocation caused by epiphyseal premature closure (EPC) are described. Deformity correction surgery was mentioned in the literature, but there were numerous complications, for example, poor correction, infection, neurovascular injury, osteofascial compartment syndrome, failure of internal fixation, and nonunion after osteotomy. In order to minimize surgical complications, we utilized navigated drilling to finish accuracy bone bridge resection and applied arthroscopy to assess wrist lesions. PATIENT CONCERNS: An 11-year-old male patient showed swelling and pain of the left wrist. DIAGNOSES: The patient was diagnosed with a postoperative of Kirschner wire internal fixation for epiphyseal injury, left lower ulnar-radial joint dislocation, left wrist deformity, and EPC. INTERVENTIONS: A NDA was used to assist the bone bridge resection in this patient. OUTCOMES: Pain was relieved clearly in the patient. Dorsiflexion increased from 60.8° to 85.3°, palmar flexion increased from 45.3° to 65.8°, supination increased from 41.3° to 69.5°, and pronation increased from 31.6° to 62.9°. The preoperative disabilities of the arm, shoulder, and hand (DASH) score was 86.1, which was increased to 16.4 postoperatively. Surgery designing lasted for 2 minutes, bone bridge resection lasted for 56 minutes, and fluoroscopic time was 2.4 minutes. Complications, for example, neurological injury, vascular injury, infection and deformity aggressive, were not found during the 5-month follow up. LESSONS: The outcome of the present study suggests that the NDA maximizes the bone bridge resection accuracy in EPC treatment, which is made efficient by reducing surgical trauma and avoiding neurovascular injury. An experience was gained that in the process of bone bridge removal, the bit of navigated drill should be continuously washed with normal saline to cool down, so as to avoid damage of nerve caused by heat conduction.

Multimodal intraoperative monitoring during surgical correction of scoliosis to avoid neurologic damage.

The purpose of this study was to evaluate the application of multimodal intraoperative monitoring (MIOM) system in patients with congenital scoliosis (CS) and adolescent idiopathic scoliosis (AIS).Twelve patients who underwent posterior surgical correction of scoliosis for CS and AIS from June 2014 to July 2018 were enrolled in this study. During the operation, we monitored the functional status of the spinal cord by MIOM. An abnormal somatosensory evoked potential was defined as a prolonged latency of more than 10% or a peak-to-peak amplitude decline of more than 50% when compared to baseline. An abnormal transcranial motor evoked potential (TcMEP) was defined as a TcMEP amplitude decrease of more than 50%. A normal triggered electromyography response, which presented with the absence of an electrical response on stimulation at 8.2 mA, indicated that the pedicle screw was not in contact with the spinal cord or nerve root.A total of 12 patients underwent MIOM surgery, of which 9 patients with negative MIOM had no significant deterioration of neurological function postoperatively, and exhibited satisfactory surgical correction of scoliosis during follow-ups. However, the remaining 3 patients suffered from MIOM events, 2 patients had normal neurological function, and 1 patient had deteriorated neurological function postoperatively.Using MIOM in CS and AIS surgery could promptly detect iatrogenic neurological injury at the early stage. Therefore, rapid response by appropriate intraoperative interventions can be taken to minimize the injury. Besides, stable MIOM recordings encourage surgeons to correct scoliosis even when the Cobb angle of scoliosis was extremely large.

A screw-view model of navigation aid retrograde transpubic screw fixation for anterior pelvic ring fracture: A case report with 28 months follow-up and technical note.

RATIONALE: The purpose of this study was to evaluate the accuracy of a retrograde transpubic screw fixation assisted by a screw-view model of navigation in treating a pelvic fracture. PATIENT CONCERNS: A 30-year-old female patient injured in a motor vehicle accident, displayed symptoms characterized by swelling and pain of the pudendum. DIAGNOSES: The patient was diagnosed with a fracture of the pubic ramus. INTERVENTIONS: We used a screw-view model of navigation to assist our retrograde transpubic screw fixation in this patient. OUTCOMES: In total, 2 screws were inserted into the bilateral pubic ramus and both were excellently positioned. It took 7.4 minutes to design the screws, 8.1 minutes to implant the guidewire, and 39.3 minutes to place the screws. Intraoperative blood loss amounted to 21 mL and the total fluoroscopic time was 3.8 minutes. No clinical complications, such as neurologic, vascular, or urologic injury, infection, screw loosening, or loss of reduction, were found after the operation. Follow-up lasted 28 months. LESSONS: The outcome of our study suggests that the screw-view model of navigation maximizes the retrograde transpubic screw insertion accuracy in the treatment of a pubic ramus fracture, which is made efficient by pain relief and early out-of-bed mobilization. Our suggestion is, therefore, that the relative position between the pubic ramus and the patient tracker must be static to ensure the accuracy of the entire system throughout the operation.

Accuracy and safety of percutaneous periacetabular screw insertion using screw view model of navigation in acetabular fracture: A case report.

RATIONALE: The purpose of this study was to estimate the efficacy and safety of percutaneous periacetabular screw (PPS) insertion assisted by screw view model of navigation (SVMN) to treat fracture of acetabulum. PATIENT CONCERNS: A 61-year-old male patient was injured in a motorcycle accident, which caused pain, swelling, deformity and limited mobility on his right hip. DIAGNOSES: He was diagnosed with fracture of acetabulum. INTERVENTIONS: We used PPS insertion assisted by SVMN to treat fracture of acetabulum in this patient. OUTCOMES: The follow up lasted 24 months. Totally 2 screws were inserted into anterior and posterior column of acetabulum respectively and both of them displayed grade 0. Compared with the preoperative gap and step of fracture displacement, the postoperative ones were significantly reduced. It took 11.7 minutes for designing the screws, 6.7 minutes for implanting the guide wire, and 45.5 minutes for placing the screws. Intraoperative blood loss was 29 mL and total fluoroscopic time was 4.1 minutes. No clinical complications such as nerve vascular injury, infection and screw loosening were found after the operation. LESSONS: The study indicated that SVMN is favorable to the PPS insertion for acetabular fracture. Our lesson is that the relative position between the acetabular and the patient tracker must be static to ensure the accuracy of the entire system throughout the operation.

Combined 3D rapid prototyping and computer navigation facilitate surgical treatment of congenital scoliosis: A case report and description of technique.

RATIONALE: This study describes the technique of combined Orbic 3D navigation (O3DN) and 3D rapid prototyping (3DRP) to assist surgical correction of congenital scoliosis. PATIENT CONCERNS: A 12-year-old boy with congenital scoliosis. His father brought him to our hospital upon noticing the boy's asymmetry of the trunk. DIAGNOSES: Congenital scoliosis. INTERVENTIONS: O3DN and 3DRP were used to assist correction surgery in this patient. OUTCOMES: The Cobb angle of segmental scoliosis (T8-L2) was 46.9° preoperatively and 2.3° at the last postoperative follow-up; correction was 95.1%. The average segmental kyphosis (T5-T12) was 45.2° preoperatively and 18.6° at the postoperative follow-up; correction was 58.9%. The preoperative sagittal imbalance of 56.2 mm was improved to 9.7 mm. The mean distance between the center sacral vertical line and the C7 plumb line was reduced from 5.7 to 4.1 mm. Operative time and bleeding volume was impressively little, with no misplacement of pedicle screws or other surgical complications. LESSONS: Combined 3DRP and O3DN helped achieve satisfactory correction for this case of congenital scoliosis. The application of 3DRP aided by O3DN in surgical treatment of congenital scoliosis can reduce operative time, lessen blood loss, reduce screw misplacement, and avoid neurovascular damage. However, patients' hospital costs were greater. Our lessons learnt are that the relative position between the tracker and the pedicle must be static to ensure the accuracy of the whole system during the entire operation.

Multimodal intraoperative monitoring during reduction of spine burst fracture and dislocation prevents neurologic injury.

This study aims to evaluate the application of multimodal intraoperative monitoring (MIOM) in surgical treatment for spine burst fracture and dislocation (SBFD) patients.Eleven patients who underwent posterior reduction and instrumentation (PRI) for SBFD from June 2014 to July 2016 were included into the study. The function of the spinal cord was monitored by MIOM. The muscle strength of the lower extremities and American Spinal Injury Association (ASIA) scores were, respectively, evaluated (before surgery, and at 1, 3, 6, and 12 months after surgery). Furthermore, the extent of reduction was also assessed.Muscle strength recovery, ASIA score changes, and the extent of reduction were correlated with MIOM results. Among the 11 patients who received surgery under MIOM, 8 patients with negative MIOM results during the operation did not demonstrate neurological deterioration postoperatively and exhibited improvements in ASIA scores during follow-ups. However, among the 3 patients who encountered MIOM events (case 4, 7, and 8), 2 patients avoided nerve lesion and 1 patient suffered from neurologic deterioration postoperatively.The application of MIOM technology during PRI surgery may detect spinal cord impairment at the early stage, and operative schemes can be modified before permanent nerve compromise is triggered by surgical manipulation.

Correlations Between Abnormal Glucose Metabolism and Bone Mineral Density or Bone Metabolism.

BACKGROUND: The aim of this meta-analysis was to explore the correlations of abnormal glucose metabolism (AGM) with bone mineral density (BMD) and bone metabolism. MATERIAL/METHODS: Relevant studies were identified using computerized and manual search strategies. The included studies were in strict accordance with inclusion and exclusion criteria. Statistical analyses were conducted with the Comprehensive Meta-analysis 2.0 (Biostat Inc., Englewood, NJ, USA). RESULTS: Our present meta-analysis initially searched 844 studies, and 7 studies were eventually incorporated in the present meta-analysis. These 7 cohort studies included 1123 subjects altogether (560 patients with AGM and 563 healthy controls). The results showed that bone mass index (BMI), insulin, and insulin resistance (IR) of patients with AGM were significantly higher than that of the population with normal glucose metabolism (BMI: SMD=1.658, 95% CI=0.663~2.654, P=0.001; insulin: SMD=0.544, 95% CI=0.030~1.058, P=0.038; IR: SMD=8.767, 95% CI=4.178~13.356, P<0.001). However, the results also indicated there was no obvious difference in osteocalcin (OC) and BMD in patients with AGM and the population with normal glucose metabolism (OC: SMD=0.293, 95% CI=-0.023~0.609, P=0.069; BMD: SMD=0.805, 95% CI=-0. 212~1.821, P=0.121). CONCLUSIONS: Our meta-analysis results suggest that AGM might lead to increased BMI, insulin, and IR, while it has no significant correlation with BMD or bone metabolism.

Does heterotopic ossification affect the outcomes of cervical total disc replacement? A meta-analysis.

STUDY DESIGN: Meta-analysis. OBJECTIVE: The purpose of this study was to answer the following questions: (1) Does heterotopic ossification (HO) negatively influence clinical outcomes after cervical total disc replacement (CTDR)? (2) Should patients be classified into HO and non-HO groups? (3) Is there a more rational classification? SUMMARY OF BACKGROUND DATA: Heterotopic ossification has emerged as a common complication after CTDR and has been an important reason for reoperation, thus limiting the use of the surgery. However, the influence of HO on clinical outcomes after CTDR has not been well established. METHODS: A meta-analysis was conducted with studies identified by searches of MEDLINE, EMBASE, and the Cochrane Library. We calculated the weighted mean differences of the visual analogue scale pain score, Neck Disability Index, and range of motion (ROM). Patients were classified into 2 groups under 3 classifications on the basis of the grade of HO. Results were pooled using a fixed effect model or a random effects model, according to the heterogeneity. RESULTS: There were significant differences in ROM under all 3 classifications. The visual analogue scale pain score and the Neck Disability Index between the patients with and without HO showed no significant difference after CTDR. Significant differences in visual analogue scale pain score were observed when patients were classified into a "high-grade HO" group (McAfee grades 3 or 4 HO) and a "low-grade HO" group (McAfee grade 0, 1, or 2 HO). CONCLUSIONS: The presence of HO is not associated with clinical outcomes after CTDR. However, the severity of HO actually impacts clinical outcomes in an inverse manner, which needs further investigation. It is inappropriate to classify patients on the basis of the presence of HO; further studies of the classifications (ROM-affecting HO vs. ROM-preserving HO; high-grade HO vs. low-grade HO) and cervical stability after CTDR are needed. LEVEL OF EVIDENCE: 2.

LIM kinase 1 is required for insulin­dependent cell growth of osteosarcoma cell lines.

Osteosarcoma is a type of malignant bone tumor with high metastasis and poor prognosis. Previous studies have demonstrated the involvement of LIM kinase 1 (LIMK1) in the proliferation of osteosarcoma cells. LIMK1 is overexpressed in human osteosarcoma tissues and cell lines. To further study LIMK1-associated mechanisms, we used shRNA targeted to the LIMK1 gene to block its expression in the osteosarcoma cell lines MG63 and U2OS. Insulin promoted the proliferation of MG63 cells in a time- and dose-dependent manner, however, this insulin induced proliferation was significantly inhibited by transfection of shRNA targeted to the LIMK1 gene, as well as by the PI3K inhibitor LY294002, but not by the mitogen­activated protein kinase (MAPK) inhibitor PD98059. The level of cofilin phosphorylation was increased significantly following stimulation of insulin for 24 h, indicating the activation of LIMK1. MG63 cell proliferation was also significantly inhibited by 1,25-dihydroxy vitamin D3 (1,25(OH)2D3) in a time-dependent manner. Furthermore, 1,25(OH)2D3 negated the inhibitory effect of LIMK1 shRNA, indicating that LIMK1 is important in the inhibitory pathway of 1,25(OH)2D3. The present study confirms that LIMK1 is important in regulating osteosarcoma cell proliferation via the insulin/PI3K/LIMK1 signaling pathway, thus the development of gene therapy for osteosarcoma targeting LIMK1 is warranted.

Ultrasound assessment of injury to the posterior ligamentous complex in patients with mild thoracolumbar fractures.

OBJECTIVE: To assess the value of ultrasonographic imaging of the posterior ligamentous complex (PLC) to diagnose ligamentous injuries, in patients with mild thoracolumbar fractures. METHODS: Patients with thoracolumbar fractures were included in this prospective study. Patients underwent palpation of the midline of the back, and ultrasonography was performed over the entire thoracolumbar region by an experienced sonographer. A team that included a musculoskeletal radiologist, an orthopaedic surgeon and a sonographer assessed the ultrasound results. Ultrasonographic and magnetic resonance imaging (MRI) findings were jointly evaluated in a subgroup of patients who were able to fund MRI analysis. Conflicts regarding the results were resolved by a majority vote. RESULTS: A total of 21 patients participated in the study, all of whom exhibited abnormal ultrasonographic echogenicity on the supraspinous or interspinous ligaments. Three patients were diagnosed with a rupture of the supraspinous ligament. In 15/17 (88.2%) patients, interspinous ligament injuries were detected caudally to the injured vertebrae. CONCLUSIONS: Ultrasound examination is a reliable complementary diagnostic tool to identify PLC injuries in patients with mild thoracolumbar fractures.