Applications of Diffusion-Weighted MRI to the Musculoskeletal System.

Diffusion-weighted imaging (DWI) is an established MRI technique that can investigate tissue microstructure at the scale of a few micrometers. Musculoskeletal tissues typically have a highly ordered structure to fulfill their functions and therefore represent an optimal application of DWI. Even more since disruption of tissue organization affects its biomechanical properties and may indicate irreversible damage. The application of DWI to the musculoskeletal system faces application-specific challenges on data acquisition including susceptibility effects, the low T2 relaxation time of most musculoskeletal tissues (2-70 msec) and the need for sub-millimetric resolution. Thus, musculoskeletal applications have been an area of development of new DWI methods. In this review, we provide an overview of the technical aspects of DWI acquisition including diffusion-weighting, MRI pulse sequences and different diffusion regimes to study tissue microstructure. For each tissue type (growth plate, articular cartilage, muscle, bone marrow, intervertebral discs, ligaments, tendons, menisci, and synovium), the rationale for the use of DWI and clinical studies in support of its use as a biomarker are presented. The review describes studies showing that DTI of the growth plate has predictive value for child growth and that DTI of articular cartilage has potential to predict the radiographic progression of joint damage in early stages of osteoarthritis. DTI has been used extensively in skeletal muscle where it has shown potential to detect microstructural and functional changes in a wide range of muscle pathologies. DWI of bone marrow showed to be a valuable tool for the diagnosis of benign and malignant acute vertebral fractures and bone metastases. DTI and diffusion kurtosis have been investigated as markers of early intervertebral disc degeneration and lower back pain. Finally, promising new applications of DTI to anterior cruciate ligament grafts and synovium are presented. The review ends with an overview of the use of DWI in clinical routine. EVIDENCE LEVEL: 5 TECHNICAL EFFICACY: Stage 3.

Functional and Surgical Outcomes of Corpectomy in Patients with Unstable Spinal Fractures.

BACKGROUND: Unstable fractures of the spine should be managed surgically. An anterior approach allows for precise decompression of the vertebral canal and reconstruction of the fractured vertebral body. The aim of the study was to evaluate the functional and surgical outcomes of anterior surgical approaches for vertebral body removal and prosthetic reconstruction. MATERIAL AND METHODS: The objectives of this paper were accomplished by reviewing the course of treatment and treatment outcomes of patients operated on at the Orthopaedic Oncology Department in Brzozw and the Department of Orthopaedics and Traumatology in District Hospital in Stalowa Wola in the years 2020-2021. In total, the treatment of 54 patients was analyzed. The study only included patients with traumatic and pathological fractures who underwent a single-level corpectomy. A total of 18 patients with fractures of the cervical spine, 15 of the thoracic spine and 21 of lumbar spine were treated. Before and after treatment, patients' neurological status was assessed according to the Frankel classification, performance was assessed with the Karnofsky score and pain intensity was analyzed with a VAS. The vertebral wedge angle (alpha), the ratio of the anterior height of the fractured vertebral body to the anterior height of the upper adjacent vertebral body (a/c), the ratio of the anterior height to the posterior height of the fractured vertebra (a/b) and the distance between the vertebral endplates adjacent to the fractured vertebra, measured between their anterior edges (A-B) were assessed. The most common general medical and surgical complications were also evaluated. RESULTS: After the surgery, significant pain relief measured using a VAS was noted (the median was 7 preoperatively and 4 postoperatively) and an improvement in performance according to the Karnofsky score was observed (the median was 50 preoperatively and 70 postoperatively). Out of the 14 patients with neurologic deficits 11 improved, while 5 regained the ability to walk. In four patients, the implant migrated into an adjacent vertebra and three patients suffered a fracture of the upper adjacent vertebra. The correction of the spine deteriorated in all 7 patients. There was no postoperative neurological deterioration of patients and no infectious complications. During the surgery, three patients suffered dura mater injury, which was identified intraoperatively and repaired. CONCLUSIONS: 1. Corpectomy followed by vertebral body replacement is an effective and safe method that enables the restoration of the shape of the vertebra, restoration of the physciological spinal curvature and direct neural decompression. 2. The treatment outcomes are good. Pain significantly decreases and performance improves in most patients. 3. Treatment complications are rare. The most often observed complication was migration of the implant into an adjacent vertebral endplate, fractures above the place of fixation and dura mater injury.

Benign vs malignant vertebral compression fractures with MRI: a comparison between automatic deep learning network and radiologist's assessment.

OBJECTIVE: To test the diagnostic performance of a deep-learning Two-Stream Compare and Contrast Network (TSCCN) model for differentiating benign and malignant vertebral compression fractures (VCFs) based on MRI. METHODS: We tested a deep-learning system in 123 benign and 86 malignant VCFs. The median sagittal T1-weighted images (T1WI), T2-weighted images with fat suppression (T2WI-FS), and a combination of both (thereafter, T1WI/T2WI-FS) were used to validate TSCCN. The receiver operator characteristic (ROC) curve was analyzed to evaluate the performance of TSCCN. The accuracy, sensitivity, and specificity of TSCCN in differentiating benign and malignant VCFs were calculated and compared with radiologists' assessments. Intraclass correlation coefficients (ICCs) were tested to find intra- and inter-observer agreement of radiologists in differentiating malignant from benign VCFs. RESULTS: The AUC of the ROC plots of TSCCN according to T1WI, T2WI-FS, and T1WI/T2WI-FS images were 99.2%, 91.7%, and 98.2%, respectively. The accuracy of T1W, T2WI-FS, and T1W/T2WI-FS based on TSCCN was 95.2%, 90.4%, and 96.2%, respectively, greater than that achieved by radiologists. Further, the specificity of T1W, T2WI-FS, and T1W/T2WI-FS based on TSCCN was higher at 98.4%, 94.3%, and 99.2% than that achieved by radiologists. The intra- and inter-observer agreements of radiologists were 0.79-0.85 and 0.79-0.80 for T1WI, 0.65-0.72 and 0.70-0.74 for T2WI-FS, and 0.83-0.88 and 0.83-0.84 for T1WI/T2WI-FS. CONCLUSION: The TSCCN model showed better diagnostic performance than radiologists for automatically identifying benign or malignant VCFs, and is a potentially helpful tool for future clinical application. CLINICAL RELEVANCE STATEMENT: TSCCN-assisted MRI has shown superior performance in distinguishing benign and malignant vertebral compression fractures compared to radiologists. This technology has the value to enhance diagnostic accuracy, sensitivity, and specificity. Further integration into clinical practice is required to optimize patient management. KEY POINTS: • The Two-Stream Compare and Contrast Network (TSCCN) model showed better diagnostic performance than radiologists for identifying benign vs malignant vertebral compression fractures. • The processing of TSCCN is fast and stable, better than the subjective evaluation by radiologists in diagnosing vertebral compression fractures. • The TSCCN model provides options for developing a fully automated, streamlined artificial intelligence diagnostic tool.

The role of bone metastases on the mechanical competence of human vertebrae.

Spine is the most common site for bone metastases. The evaluation of the mechanical competence and failure location in metastatic vertebrae is a biomechanical and clinical challenge. Little is known about the failure behaviour of vertebrae with metastatic lesions. The aim of this study was to use combined micro-Computed Tomography (microCT) and time-lapsed mechanical testing to reveal the failure location in metastatic vertebrae. Fifteen spine segments, each including a metastatic and a radiologically healthy vertebra, were tested in compression up to failure within a microCT. Volumetric strains were measured using Digital Volume Correlation. The images of undeformed and deformed specimens were overlapped to identify the failure location. Vertebrae with lytic metastases experienced the largest average compressive strains (median ± standard deviation: -8506 ± 4748microstrain), followed by the vertebrae with mixed metastases (-7035 ± 15605microstrain), the radiologically healthy vertebrae (-5743 ± 5697microstrain), and the vertebrae with blastic metastases (-3150 ± 4641microstrain). Strain peaks were localised within and nearby the lytic lesions or around the blastic tissue. Failure between the endplate and the metastasis was identified in vertebrae with lytic metastases, whereas failure localised around the metastasis in vertebrae with blastic lesions. This study showed for the first time the role of metastases on the vertebral internal deformations. While lytic lesions lead to failure of the metastatic vertebra, vertebrae with blastic metastases are more likely to induce failure in the adjacent vertebrae. Nevertheless, every metastatic lesion affects the vertebral deformation differently, making it essential to assess how the lesion affects the bone microstructure. These results suggest that the properties of the lesion (type, size, location within the vertebral body) should be considered when developing clinical tools to predict the risk of fracture in patients with metastatic lesions.

Bone Marrow Adiposity and Fragility Fractures in Postmenopausal Women: The ADIMOS Case-Control Study.

CONTEXT: Noninvasive assessment of proton density fat fraction (PDFF) by magnetic resonance imaging (MRI) may improve the prediction of fractures. OBJECTIVE: This work aimed to determine if an association exists between PDFF and fractures. METHODS: A case-control study was conducted at Lille University Hospital, Lille, France, with 2 groups of postmenopausal women: one with recent osteoporotic fractures, and the other with no fractures. Lumbar spine and proximal femur (femoral head, neck, and diaphysis) PDFF were determined using chemical shift-based water-fat separation MRI (WFI) and dual-energy x-ray absorptiometry scans of the lumbar spine and hip. Our primary objective was to determine the relationship between lumbar spine PDFF and osteoporotic fractures in postmenopausal women. Analysis of covariance was used to compare PDFF measurements between patient cases (overall and according to the type of fracture) and controls, after adjusting for age, Charlson comorbidity index (CCI) and BMD. RESULTS: In 199 participants, controls (n = 99) were significantly younger (P < .001) and had significantly higher BMD (P < 0.001 for all sites) than patient cases (n = 100). A total of 52 women with clinical vertebral fractures and 48 with nonvertebral fractures were included. When PDFFs in patient cases and controls were compared, after adjustment on age, CCI, and BMD, no statistically significant differences between the groups were found at the lumbar spine or proximal femur. When PDFFs in participants with clinical vertebral fractures (n = 52) and controls were compared, femoral neck PDFF and femoral diaphysis PDFF were detected to be lower in participants with clinical vertebral fractures than in controls (adjusted mean [SE] 79.3% [1.2] vs 83.0% [0.8]; P = 0.020, and 77.7% [1.4] vs 81.6% [0.9]; P = 0.029, respectively). CONCLUSION: No difference in lumbar spine PDFF was found between those with osteoporotic fractures and controls. However, imaging-based proximal femur PDFF may discriminate between postmenopausal women with and without clinical vertebral fractures, independently of age, CCI, and BMD.

Bone Marrow Adipose Tissue Is Increased in Postmenopausal Women With Postsurgical Hypoparathyroidism.

CONTEXT: Suppression of bone turnover, greater trabecular volume, and normal-high normal all-site bone mineral density (BMD) are hallmarks of postsurgical hypoparathyroidism (HypoPT). Impairment in the trabecular microarchitecture with possible higher risk of vertebral fractures (VF) in women with postmenopausal HypoPT has also been described. Currently, no data on bone marrow adipose tissue (BMAT) are available in HypoPT. OBJECTIVE: To assess BMAT by magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (1H-MRS) in postmenopausal women with chronic postsurgical HypoPT. METHODS: This cross-sectional pilot study, conducted at an ambulatory referral center, included 29 postmenopausal women (mean age 66 ± 8.4 years) with postsurgical HypoPT and 31 healthy postmenopausal women (mean age 63 ± 8.5). Lumbar spine MRI was performed and BMAT was measured by applying PRESS sequences on the L3 body. Lumbar spine, femoral neck, and total hip BMD were measured by dual x-ray absorptiometry (DXA); site-matched spine trabecular bone score (TBS) was calculated by TBS iNsight (Medimaps, Switzerland); VF assessment was performed with lateral thoracic and lumbar spine DXA. RESULTS: Fat content (FC) and saturation level (SL%) were higher (P <.0001 and P <.001), while water content (W) was lower in HypoPT compared to controls (P <.0001). FC significantly correlated with years since menopause and body weight (P <.05) in HypoPT, while TBS negatively correlated with FC and SL% (P <.05) and positively with residual lipids (RL) and W (P <.05). CONCLUSION: We demonstrate for the first time that BMAT is increased in postmenopausal women with postsurgical hypoparathyroidism and negatively associated with trabecular microarchitecture.

Thoracolumbar Injury: The Thoracolumbar Injury Classification and Severity Scoring System or Modified Thoracolumbar Injury Classification and Severity?

OBJECTIVE: To compare the Thoracolumbar Injury Classification and Severity (TLICS) scoring system with its modified (mTLICS) version based on their agreement with the surgeon's opinion regarding treatment for patients with thoracolumbar injuries. Moreover, the Posterior Ligamentous Complex health was compared between intraoperative examinations and magnetic resonance imaging (MRI) reports. METHODS: MRI was obtained from 114 patients suffering thoracolumbar spinal trauma; the TLICS and mTLICS scores were measured. Approaches 1 and 2 were designed in both scoring systems based on assuming a total score of 4 as surgery and conservative management indication, respectively. Kappa was used to estimate the agreements between each approach and the surgeon's opinion on treatment. The receiver operating curve calculated the appropriate cut-off scores for the above systems over which surgical management was preferred. A P < 0.05 was considered significant. RESULTS: All the approaches showed moderate agreements with the surgeon's opinion on therapeutic management (TLICS: κapproach1 = 0.557, κapproach2 =0.508; mTLICS: κapproach1 = 0.557, κapproach2 = 0.551; P < 0.001 for each κ). A score >3.5 best illustrated the indication for surgery in both systems. The radiology report agreed stronger with intraoperatively observed ligamentous health when suspicious cases on MRI were reported as injured (κTLICS = 0.830, κmTLICS = 0.704) rather than healthy (κTLICS = 0.620, κmTLICS = 0.620). CONCLUSIONS: The surgeon's treatment plan agreed moderately with suggestions of the TLICS and mTLICS systems; surgery was the preferred management for the patients with a score of 4. Moreover, radiologic suspicion of Posterior Ligamentous Complex injury seemed to indicate a damaged ligament rather than a healthy one.

Balloon kyphoplasty for cervical spine metastasis: a technical note.

We report a simple technique of cervical spine balloon kyphoplasty performed for painful osteolytic metastatic disease in two patients.

Vertical split fracture of the vertebral body following oblique lumbar interbody fusion: A case report.

RATIONALE: Oblique lumbar interbody fusion (OLIF) is an effective and safe surgical technique widely used for treating spondylolisthesis; however, its use is controversial because of several associated complications, including endplate injury. We report a rare vertebral body fracture following OLIF in a patient with poor bone quality. PATIENT CONCERNS: A 72-year-old male patient visited our clinic for 2 years with lower back pain, leg radiating pain, and intermittent neurogenic claudication. DIAGNOSES: Lumbar magnetic resonance imaging revealed L4-5 stenosis. INTERVENTION: We performed OLIF with percutaneous pedicle screw fixation and L4 subtotal decompressive laminectomy. We resected the anterior longitudinal ligament partially for anterior column release and inserted a huge cage to maximize segmental lordosis. No complications during and after the operation were observed. Further, the radiating pain and back pain improved, and the patient was discharged. Two weeks after the operation, the patient visited the outpatient department complaining of sudden recurred pain, which occurred while going to the bathroom. Radiography and computed tomography revealed a split fracture of the L5 body and an anterior cage displacement. In revision of OLIF, we removed the dislocated cage and filled the bone cement between the anterior longitudinal ligament and empty disc space. Further, we performed posterior lumbar interbody fusion L4-5, and the screw was extended to S1. OUTCOMES: After the second surgery, back pain and radiating pain in the left leg improved, and he was discharged without complications. LESSON: In this case, owing to insufficient intervertebral space during L4-5 OLIF, a huge cage was used to achieve sufficient segmental lordosis after anterior column release, but a vertebral body coronal fracture occurred. In patients with poor bone quality and less flexibility, a huge cage and over-distraction could cause a vertebral fracture; hence, selecting an appropriate cage or considering a posterior approach is recommended.

Influence of Metastatic Bone Lesion Type and Tumor Origin on Human Vertebral Bone Architecture, Matrix Quality, and Mechanical Properties.

Metastatic spine disease is incurable, causing increased vertebral fracture risk and severe patient morbidity. Here, we demonstrate that osteolytic, osteosclerotic, and mixed bone metastasis uniquely modify human vertebral bone architecture and quality, affecting vertebral strength and stiffness. Multivariable analysis showed bone metastasis type dominates vertebral strength and stiffness changes, with neither age nor gender having an independent effect. In osteolytic vertebrae, bone architecture rarefaction, lower tissue mineral content and connectivity, and accumulation of advanced glycation end-products (AGEs) affected low vertebral strength and stiffness. In osteosclerotic vertebrae, high trabecular number and thickness but low AGEs, suggesting a high degree of bone remodeling, yielded high vertebral strength. Our study found that bone metastasis from prostate and breast primary cancers differentially impacted the osteosclerotic bone microenvironment, yielding altered bone architecture and accumulation of AGEs. These findings indicate that therapeutic approaches should target the restoration of bone structural integrity. © 2022 American Society for Bone and Mineral Research (ASBMR).

Surgical fixation of pathologic and traumatic spinal fractures using single position surgery technique in lateral decubitus position.

STUDY DESIGN: Retrospective Case Series. OBJECTIVES: This study aims to determine complications, readmission, and revision surgery rates in patients undergoing single position surgery (SPS) for surgical treatment of traumatic and pathologic thoracolumbar fractures. METHODS: A multi-center review of patients who underwent SPS in the lateral decubitus position (LSPS) for surgical management of traumatic or pathologic thoracolumbar fractures between January 2016 and May 2020 was conducted. Operative time, estimated blood loss (EBL), intraoperative complications, postoperative complications, readmissions, and revision surgeries were collected. RESULTS: A total of 12 patients with a mean age of 45 years (66.67% male) were included. The majority of patients underwent operative treatment for acute thoracolumbar trauma (66.67%) with a mean injury severity score (ISS) of 16.71. Mean operative time was 175.5 min, mean EBL of 816.67 cc. Five patients experienced a complication, two of which required revision surgery for additional decompression during the initial admission. All ambulatory patients were mobilized on postoperative day 1. The mean hospital length of stay (LOS) was 9.67 days. CONCLUSION: The results of this case series supports LSPS as a feasible alternative to the traditional combined anterior-posterior approach for surgical treatment of pathologic and thoracolumbar fractures. These results are similar to reductions in operative time, EBL, and LOS seen in the elective spine literature with LSPS. LEVEL OF EVIDENCE: IV.

High viscosity bone cement vertebroplasty versus low viscosity bone cement vertebroplasty in the treatment of mid-high thoracic vertebral compression fractures.

BACKGROUND CONTEXT: As science and technology have advanced, novel bone cements with numerous formulated ingredients have greatly evolved and been commercialized for vertebroplasty. Recently, viscosity has been a focus to achieve better clinical outcomes and fewer complications. Meanwhile, the experience in the treatment of mid (T7-9) to high (T4-6) thoracic vertebral compression fractures is limited. PURPOSE: The objective of this study was to identify the different outcomes between high-viscosity bone cement (HVBC) and low-viscosity bone cement (LVBC) used to repair mid (T7-9)- and high (T4-6)- thoracic vertebral compression fractures. STUDY DESIGN/SETTING: This study was a single-center, retrospective cohort study PATIENT SAMPLE: A consecutive series of 107 patients with a total of 144 vertebrae was included. OUTCOME MEASURES: The anterior vertebral height (AVH), middle vertebral height (MVH), posterior vertebral height (PVH), local kyphotic angle (KA), Cobb angle (CA), and other associated parameters were evaluated radiologically at several time points-preoperative, surgery day 0, postoperative day 1, and 6-month follow-up. Pain evaluation was assessed by using a visual analog scale (VAS) before and 6 months after the procedure. METHODS: The patients were divided into two groups according to the viscosity of the bone cement used, and plain film and magnetic resonance imaging (MRI) of the vertebrae were used to calculate parameters. The patient characteristics; bone cement brand; changes in AVH, MVH, PVH, KA, CA, and VAS; and complications of each patient were recorded and then analyzed. RESULTS: Both groups showed increased vertebral body height, corrected KA, and CA after vertebroplasty. There were no significant differences between the HVBC and LVBC groups (ΔAVH: 2.19±2.60 vs. 2.48±3.09, p=.555; ΔMVH: 1.25±3.15 vs. 1.89±2.58, p=.192; ΔKA: -5.46±4.58 vs -5.37±4.47, p=.908; and ΔCA: -4.22±4.23 vs. -4.56±5.17, p=.679). There were significant preoperative to postoperative and preoperative to follow-up changes in AVH (HVBC, p=.012 and .046, respectively; LVBC, p=.001 and .015, respectively); a significant preoperative to postoperative change in MVH (HVBC, p=.045; LVBC, p=.001); and significant preoperative to postoperative and preoperative to follow-up changes in KA and CA (KA: HVBC, p=0.000 and .003, respectively; LVBC, p=.000 and .000, respectively; CA: HVBC, p=.017 and .047, respectively; LVBC, p=.006 and .034, respectively). The volume of cement injected was significantly higher with HVBC (3.66±1.36 vs. 3.11±1.53, p=.024), and the use of HVBC was associated fewer cases with cement leakage (26 vs. 45, p=.002). Furthermore, there was no difference between the groups in the incidence of adjacent fracture. Both groups showed an improved VAS score at follow-up, with statistically greater improvement in the HVBC group (2.40±1.53 vs. 3.07±1.69, p=.014). Moreover, significantly fewer patients with a VAS score ≥ 3 were found in the HVBC group (22 vs. 39, p=.004) CONCLUSIONS: HVBC and LVBC are safe and effective to treat mid-to-high level thoracic vertebral compression fractures. Compared with LVBC, HVBC shows less cement leakage, a greater injection volume, and better postoperative pain relief.

Risk factors for intraoperative endplate injury during minimally-invasive lateral lumbar interbody fusion.

During lateral lumbar interbody fusion (LLIF), unintended intraoperative endplate injury (IEPI) can occur and thereafter lead cage subsidence. The aim of this study was to investigate the incidence of IEPI during LLIF, and its predisposing factors. A retrospective review was conducted on consecutive patients (n = 186; mean age, 70.0 ± 7.6 years) who underwent LLIF at 372 levels. Patient's demographic and surgical data were compared between patients with and without IEPI. Also, the radiographic data of each level were compared between intact and IEPI segments. IEPI was identified at 76 levels (20.4%) in 65 patients. The incidences of IEPI at every 100 consecutive segments were not different. When 372 segments were analyzed independently, sagittal disc angle (DA) in the extended position (4.3° ± 3.6° at IEPI segments vs. 6.4° ± 4.0° at intact segments), the difference between sagittal DA in the extended position and cage angle (- 2.2° ± 4.0° vs. 0.0° ± 3.9°), and the difference between preoperative disc height and cage height (- 5.4 mm ± 2.4 mm vs. - 4.7 mm ± 2.0 mm) were different significantly. Also, endplate sclerosis was more common at intact segments than IEPI segments (33.2% vs. 17.3%). Multivariate analysis showed that male sex (odds ratio [OR] 0.160; 95% confidence interval [CI] 0.036-0.704), endplate sclerosis (OR 3.307; 95% CI 1.450-8.480), and sagittal DA in the extended position (OR 0.674; 95% CI 0.541-0.840) were significant associated factors for IEPI. IEPI was correlated not with surgeon's experience, but with patient factors, such as sex, preoperative disc angle, and endplate sclerosis. Careful surgical procedures should be employed for patients with these predisposing factors.

Clinical and imaging features of surgically treated low lumbar osteoporotic vertebral collapse in patients with Parkinson's disease.

Osteoporosis and Parkinson's disease (PD) are age-related diseases, and surgery for osteoporotic vertebral collapse (OVC) in PD patients become more common. OVC commonly affects the thoracolumbar spine, but low lumbar OVC is frequent in patients with lower bone mineral density (BMD). The aim of this study was to identify differences in clinical and imaging features of low lumbar OVC with or without PD and to discuss the appropriate treatment. The subjects were 43 patients with low lumbar OVC below L3 who were treated surgically, including 11 patients with PD. The main clinical symptoms were radicular pain in non-PD cases and a cauda equina sign in PD cases. Rapid progression and destructive changes of OVC were seen in patients with PD. The morphological features of OVC were flat-type in non-PD cases with old compression fracture, and destruction-type in PD cases without old compression fracture. Progression of PD was associated with decreased lumbar lordosis, lower lumbar BMD, and severe sarcopenia. High postoperative complication rates were associated with vertebral fragility and longer fusion surgery. Progression of postural instability as a natural course of PD may lead to mechanical stress and instrumentation failure. Invasive long-fusion surgery should be avoided for single low lumbar OVC.

The Association Between Cholecystectomy and the Risk for Fracture: A Nationwide Population-Based Cohort Study in Korea.

Objectives: To evaluate the risk of fracture in individuals with a history of cholecystectomy in Korean population. Methods: Individuals (n = 143,667) aged ≥ 40 y who underwent cholecystectomy between 2010 and 2015 and the controls (n = 255,522), matched by age and sex, were identified from the database of the Korean National Health Insurance Services. The adjusted hazard ratio (aHR) and 95% confidence interval (CI) of fracture were estimated following cholecystectomy, and a Cox regression analysis was performed. Results: The incidence rates of all fractures, vertebral, and hip fractures were 14.689, 6.483 and 1.228 cases per 1000 person-years respectively in the cholecystectomy group, whereas they were 13.862, 5.976, and 1.019 cases per 1000 person-years respectively in the control group. After adjustment for age, sex, income, place of residence, diabetes mellitus, hypertension, dyslipidemia, smoking, alcohol drinking, exercise, and body mass index, patients who underwent cholecystectomy showed an increased risk of all fractures, vertebral fractures, and hip fractures (aHR [95% CI]: 1.095 [1.059-1.132], 1.134 [1.078-1.193], and 1.283 [1.139-1.444] for all fractures, vertebral fractures, and hip fractures, respectively). The risk of vertebral fractures following cholecystectomy was more prominent in the young age group (40 to 49 y) than in the old age group (≥ 65 y) (1.366 [1.082-1.724] vs. 1.132 [1.063-1.206], respectively). However, the incidence of hip fractures following cholecystectomy was not affected by age. Conclusion: Individuals who underwent cholecystectomy have an increased risk of fracture. In the younger population, the risk of vertebral fractures may be further increased following cholecystectomy.

By inhibiting ADCY5, miR-18a-3p promotes osteoporosis and possibly contributes to spinal fracture.

To investigate the influence of miR-18a-3p and ADCY5 on OP and osteogenic differentiation of human Mesenchymal stem cell (hBMSCs) and its possible mechanism. Samples were collected from osteoporotic patients with or without vertebral compression fracture, and without OP volunteers. MiR-18a-3p and ADCY5 mRNA expression levels in the tissue samples and hBMSCs during osteogenic differentiation were detected。MiR-18a-3p mimic and OE-ADCY5 were introduced into hBMSCs to research the effects of miR-18a-3p and ADCY5 on osteogenesis differentiation of hBMSCs. Dual luciferase reporter system and RNA pull-down were applied to determine whether ADCY5 was a target gene of miR-18a-3p. Compared with the control group, ADCY5 expression level was down-regulated in patients with OP-no-Frx and OP-Frx, but that of miR-18a-3p was up-regulated. In addition, ADCY5 increased during osteogenesis differentiation of hBMSCs, whereas miR-18a-3p did not. OE-ADCY5 significantly facilitated calcium deposition, ALP activity, osteoblast protein expression (OSX, ALP and EUNX2), miR-18a-3p mimic inhibited osteogenic differentiation, and partially reversed the effect of OE-ADCY5 on osteogenic differentiation. In general, miR-18a-3p targets ADCY5 to promote OP and may be involved in spinal fracturs.

Biomechanical influence of the surgical approaches, implant length and density in stabilizing ankylosing spondylitis cervical spine fracture.

Ankylosing spondylitis cervical spine fractures (ASCFs) are particularly unstable and need special consideration when selecting appropriate internal fixation technology. However, there is a lack of related biomechanical studies. This study aimed to investigate the biomechanical influence of the pattern, length, and density of instrumentation for the treatment of ASCF. Posterior, anterior, and various combined fixation approaches were constructed using the finite element model (FEM) to mimic the surgical treatment of ASCFs at C5/6. The rate of motion change (RMC) at the fractured level and the internal stress distribution (ISD) were observed. The results showed that longer segments of fixation and combined fixation approaches provided better stability and lowered the maximal stress. The RMC decreased more significantly when the length increased from 1 to 3 levels (302% decrease under flexion, 134% decrease under extension) than from 3 to 5 levels (22% decrease under flexion, 23% decrease under extension). Longer fixation seems to be more stable with the anterior/posterior approach alone, but 3-level posterior fixation may be the most cost-effective option. It is recommended to perform surgery with combined approaches, which provide the best stability. Long skipped-screwing posterior fixation is an alternative technique for use in ASCF patients.

Experience in surgical treatment of type â ¡ odontoid fractures: A report of two cases and review of the literature.

Two cases of type Ⅱ odontoid fractures were reported to share our experience in surgery treatment of such cases. A 33-year-old woman with comminuted type Ⅱ odontoid fracture and a 42-year-old man with fracture end hardened type Ⅱ odontoid fracture received surgical treatment in our hospital. Though imaging examination suggested that these two patients were suitable for anterior screw fixation, we encountered difficulties during the operation. The two patients eventually underwent posterior C1-C2 fusion surgery and recovered well. According to the experience of these two cases, we found that the fracture line angle and the degree of comminution are two important factors affecting surgical decision-making. Although anterior screw fixation is the ideal choice for type Ⅱ odontoid fractures with anterior superior to posterior inferior fracture line, it may not be the best choice for comminuted or fracture end hardened type Ⅱ odontoid fractures.

Radiological healing of lumbar spine stress fractures in elite cricket fast bowlers.

OBJECTIVES: Review magnetic resonance imaging (MRI) of elite adult fast bowlers with a history of lumbar spine stress fracture for evidence of bone healing. The findings will determine whether bone healing can occur in this population, and whether MRI may be used as a tool to assess bone healing and inform clinical decision making. DESIGN: Retrospective cohort. METHODS: Participants were elite Australian fast bowlers who sustained a lumbar spine stress fracture confirmed on MRI and had at least one subsequent MRI. Two radiologists independently reviewed all images. RESULTS: Thirty-one fractures from 20 male fast bowlers were reviewed. Median maximum fracture size was 6mm (range 2-25mm). Twenty-five fractures achieved bone healing, with a median 203 (IQR 141-301) days between the initial MRI (to confirm diagnosis) and the MRI when bone healing was observed. Fracture size and signal intensity of bone marrow oedema were positively associated with the number of days to the MRI when bone healing was observed (r2=0.245, p<0.001 and r2=0.292, p<0.001 respectively). Fractures which occurred at the same site as a previously united fracture took longer to heal than the first fracture (median 276 days to the MRI when bone healing was observed compared to 114 days for first fracture; p=0.036). CONCLUSIONS: Lumbar spine stress fractures in elite adult fast bowlers are capable of achieving complete bone healing, as demonstrated in the majority of bowlers in this study. Larger fractures, greater bone marrow oedema, and history of previous injury at the same site may require longer healing time which may be monitored with MRI.