Endplate Fracture Research Articles

9379 From Diagnosis To Treatment: A Comprehensive Approach To Pregnancy-Related Osteoporosis With Teriparatide

Abstract Disclosure: C. Hubers: None. M. Renzu: None. V. Mehta: None. A. Manzoor Qazi: None. A.M. Satei: None. D.K. Yerasuri: None. Introduction: Pregnancy and lactation related osteoporosis (PLO) is a rare but serious condition with significant consequences for maternal and fetal health. Teriparatide's efficacy in treating this condition is promising, particularly given concerns about bisphosphonate use in this population. Clinical Case: A 26-year-old white female sought evaluation for concerns arising after her first pregnancy. Following delivery via Cesarean section, she experienced acute back pain, instability while walking and frequent falls. A subsequent bone scan showed superior end plate fractures of T9, T11, T12, and L1, while an MRI of the lumbosacral spine showed mild acute to subacute compression deformities involving the superior endplates of the L2-L5 vertebral bodies. Despite having Factor V Leiden disease, her medical history is unremarkable for significant chronic conditions or comorbidities affecting bone health. Bone density scans revealed a Z-score of -2.4 in the lumbar spine and -1.6 in the total hip, with a femoral neck Z-score of -1.3. Her lumbar spine T-score was reported as -2.8, reflecting significant bone mineral density (BMD) loss with a BMI of 20.67. She underwent thorough testing to rule out other potential contributory conditions, such as celiac disease and hemochromatosis, but was eventually diagnosed with PLO. Treatment was initiated with teriparatide, administered as a daily 20 µg subcutaneous injection. The patient demonstrated an excellent response, with marked improvements in pain and enhanced ability to perform daily activities. After treatment with teriparatide, the patient’s c-telopeptide also improved. Discussion: PLO is a very rare manifestation of osteoporosis, mainly affecting women with lower BMI and advanced age. The etiology involves hormonal changes, increased calcium demands during pregnancy and lactation, and decreased BMD. Our patient's history and clinical course highlight a compelling instance of PLO, likely attributed to decreased estrogen exposure secondary to amenorrhea and breastfeeding, resulting in increased bone turnover. While bisphosphonates are often recommended for PLO, concerns about safety in pregnant and lactating women underscore the need for alternative treatments like teriparatide. Potential effects on gestational age, neonatal birth weight, and neonatal calcium levels have been observed in newborns with maternal exposure to bisphosphonates. Teriparatide is a synthetic form of parathyroid hormone that works primarily by stimulating osteoblast activity, leading to increased bone formation and BMD. It also enhances calcium and phosphate absorption in the kidneys and intestines, further contributing to its bone-building effects. Our patient's response to teriparatide emphasizes its potential as a safer option in managing PLO, warranting further research to establish comprehensive management guidelines. Presentation: 6/3/2024

Perioperative Complications of Oblique Lumbar Interbody Fusion (OLIF): 5 Years of Experience with OLIF

Abstract Objective The objective of this study was to share our early experience with oblique lumbar interbody fusion (OLIF), with emphasis on the perioperative complications and determine clinical outcomes following OLIF. Materials and Methods It was a retrospective prospective study performed at a single institute from March 2019 to August 2023. A total of 56 consecutive patients who had undergone OLIF for degenerative spine disorders were enrolled in the study. Pre-, intra-, and postoperative data on these patients were collected. All the patients were followed up at regular intervals with an evaluation of Visual Analog Scale (VAS), Oswestry Disability Index (ODI), neurological parameters, and X-rays to look for fusion, screw loosening, pseudoarthrosis, and cage slippage. Statistical analysis was done with the odds ratio, chi-square test, and Student's t-test. A p-value of < 0.05 was considered significant. Results The overall incidence of complications was 25%, with no mortality. Intraoperative complications were noted in 10.7% of cases. This included endplate fractures (n = 3), peritoneal lacerations (n = 2), and ureteric injury (n = 1). The most common early postoperative complications were postoperative ileus (n = 6), followed by anterior thigh or groin numbness (n = 3), ipsilateral psoas weakness (n = 2), and superficial surgical site infection (n = 2). Of the late postoperative complications, cage subsidence was the most common, which occurred in 4 patients, followed by adjacent segment degeneration (n = 2) and loss of indirect decompression (n = 1). The mean ODI and VAS scores showed significant improvement (p < 0.05) at the final follow-up. Conclusion OLIF is a promising surgical technique with the potential to treat a variety of degenerative conditions of the lumbar spine with a good clinical outcome. Despite its various benefits, OLIF can lead to complications in rare instances, which every spine surgeon should be aware of.

The Different Influence of Cutibacterium acnes and Staphylococcus epidermidis in the Lumbar Disc : An in Vivo Study in Rabbits.

Animal laboratory study. This study investigated the effects of Cutibacteriumacnes and Staphylococcusepidermidis on the lumbar discs of rabbits, as well as the outcomes of combined infection. Many studies have indicated that bacterial infections are associated with lumbar disc degeneration (LDD). The most commonly cultured bacteria from disc tissues are C. acnes and S. epidermidis . New Zealand white rabbits (n=40) were randomly divided into control, C. acnes , S. epidermidis , and C. acnes plus S. epidermidis ( i.e. , combined) groups. All groups except the control were injected with 25μL of saline at L4-L5 and 25μL of bacteria (1×10 7 CFU/mL) at L5-L6. All injections were performed under x-ray guidance. Weight measurements, haematological evaluations, and magnetic resonance imaging were performed after 4, 8, and 12 weeks. Histological examination and gene expression detection were performed 12 weeks after surgery. Inflammatory factors in the blood and weight did not differ among the groups after 4, 8, and 12 weeks ( P >0.05). However, after 4 weeks, LDD occurred in the C. acnes group, and discitis occurred in the S. epidermidis and combined groups, all of which worsened after 8 weeks. After 12 weeks, the nucleus pulposus (NP) protruded and compressed the spinal cord in the C. acnes group, and tissue staining showed decreased NP tissue and cartilaginous endplate fracture. In the S. epidermidis and combined groups, the discitis was more confined, but tissue staining revealed a significant decrease in NP tissue, and loss of the normal disc structure. In the early stage of infection in rabbits, C. acnes caused LDD, and S. epidermidis caused discitis. Coinfection with C. acnes and S. epidermidis caused discitis but was more limited in scope than infection with S. epidermidis alone.

Cyclic Mechanism Affects Lumbar Spine Creep Response.

This study aims to explore how cyclic loading influences creep response in the lumbar spine under combined flexion-compression loading. Ten porcine functional spinal units (FSUs) were mechanically tested in cyclic or static combined flexion-compression loading. Creep response between loading regimes was compared using strain-time histories and linear regression. High-resolution computed tomography (µCT) visualized damage to FSUs. Statistical methods, ANCOVA and ANOVA, assessed differences in behavior between loading regimes. Cyclic and static loading regimes exhibited distinct creep response patterns and biphasic response. ANCOVA and ANOVA analyses revealed significant differences in slopes of creep behavior in both linear phases. Cyclic tests consistently showed endplate fractures in µCT imaging. The study reveals statistically significant differences in creep response between cyclic and static loading regimes in porcine lumbar spinal units under combined flexion-compression loading. The observed biphasic behavior suggests distinct phases of tissue response, indicating potential shifts in load transfer mechanisms. Endplate fractures in cyclic tests suggest increased injury risk compared to static loading. These findings underscore the importance of considering loading conditions in computational models and designing preventive measures for occupations involving repetitive spinal loading.

Mechanical consequences to the annulus fibrosus following rapid internal pressurization and endplate fracture under restrained-expansion conditions

Intervertebral disc herniation is not a common injury in the adolescent population, but the correlation between trauma and herniation warrants concern. Previous research demonstrated the capacity for rapid internal pressurization to reduce the mechanical integrity of the intervertebral disc's annulus fibrosus, even in the absence of fracture. The purpose of this study was to modify previous internal pressurization procedures towards a more transferable injury model, then investigate the capacity for these procedures to damage the mechanical integrity of the annulus fibrosus. Porcine cervical motion segments with intact facet joints were confined between a vice and force plate under 300 N of static compression, then a single, manual, rapid internal pressurization was delivered. Posterolateral annulus samples were extracted and situated in a 180° peel test configuration, exposing the interlamellar matrix of samples to separations of 0.5 mm/s, until complete separation of the sample occurred. Multilayer tensile testing was performed on superficial and mid-span samples of annulus by applying uniaxial tension of 1 %/s to 50 % strain. Compared to unpressurized controls, rapid pressurization causing fracture resulted in reduced lamellar adhesion and increased toe-region stress and strain properties in the annulus. Morphological assessment reported similar fracture patterns between endplate fractures achieved in the present experiment and endplate fractures documented in human patients. Mechanical plus morphological results suggest that rapid internal pressurization resulting in endplate fracture may represent a potent mechanism for subsequent damage to the intervertebral disc.

Human and Porcine Lumbar Endplate Injury Risk in Repeated Flexion-Compression.

Low back pain (LBP) affects 50-80% of adults at some pointin their lifetime, yet the etiology of injury is not well understood. Those exposed to repeated flexion-compression are at a higher risk for LBP, such as helicopter pilots and motor vehicle operators. Animal injury models offer insight into in vivo injury mechanisms, but interspecies scaling is needed to relate animal results to human. Human (n = 16) and porcine (n = 20) lumbar functional spinal units (FSUs) were loaded in repeated flexion-compression (1Hz) to determine endplate fracture risk over long loading exposures. Flexion oscillated from 0 to 6° and peak applied compressivestress ranged from 0.65 to 2.38MPa for human and 0.64 to 4.68MPa for porcine specimens. Five human and twelve porcine injuries were observed. The confidence intervals for human and porcine 50% injury risk curves in terms of stress and cycles overlapped, indicating similar failure behavior for this loading configuration. However, porcine specimens were more tolerant to the applied loading compared to human, demonstrated by a longer time-to-failure for the same applied stress. Optimization revealed that time-to-failure in human specimens was approximately 25% that of porcine specimens at a given applied stress within 0.65-2.38MPa. This study determined human and porcine lumbar endplate fracture risks in long-duration repeated flexion-compression that can be directly used for future equipment and vehicle design, injury prediction models, and safety standards. The interspecies scale factor produced in this study can be used for previous and future porcine lumbar injury studies to scale results to relevant human injury.

Detection and Characterization of Endplate Structural Defects on CT: A Diagnostic Accuracy Study.

Diagnostic test study. To determine the reliability and validity or diagnostic accuracy of two previously described endplate structural defect (EPSD) assessment methods. Studies of EPSD may further the understanding of pathoanatomic mechanisms underlying back pain. However, clinical imaging methods used to document EPSD have not been validated, leaving uncertainty about what the observations represent. Using an evaluation manual, 418 endplates on CT sagittal slices obtained from 19 embalmed cadavers (9 men and 10 women, aged 62-91yr) were independently assessed by two experienced radiologists and a novice for EPSD using the two methods. The corresponding micro-CT (µCT) from the harvested T7-S1 spines were assessed by another independent rater with excellent intra-rater reliability (k=0.96). Inter-rater reliability was good for the presence (k=0.60-0.69) and fair for specific phenotypes (k=0.43-0.58) of EPSD. Erosion, for which the Brayda-Bruno classification lacked a category, was mainly (82.8%) classified as wavy/irregular, while many notched defects (n=15, 46.9%) and Schmorl's nodes (n=45, 79%) were recorded as focal defects using Feng's classification. When compared to µCT, endplate fractures (n=53) and corner defects (n=28) were routinely missed on CT. Endplates classified as wavy/irregular on CT corresponded to erosion (n=29, 21.2%), jagged defects (n=21, 15.3%), calcification (n=19, 13.9%), and other phenotypes on µCT. Some focal defects on CT represented endplate fractures (n=21, 27.6%) on µCT. Overall, with respect to the presence of an EPSD, there was a sensitivity of 70.9% and a specificity of 79.1% using Feng's method, and 79.5% and 57.5% using Brayda-Bruno's method. Poor to fair inter-rater reliability (k=0.26-0.47) was observed for defect dimensions. There was good inter-rater reliability and evidence of criterion validity supporting assessments of EPSD presence using both methods. However, neither method contained all needed EPSD phenotypes for optimal sensitivity, and specific phenotypes were often misclassified.

Use of a Smartphone Digital Goniometer Combined with the Freehand Pedicle-Probing Technique for Repair of a Comminuted L6 Fracture in a 4 kg Dog

AbstractA 10-month-old, 4 kg, Bichon Frise cross was referred for surgical stabilization of a highly comminuted L6 vertebral fracture after a road traffic accident. Nonambulatory paraparesis was present, with weak voluntary motor function in both pelvic limbs. Computed tomography (CT) of T6 to Cd1 identified a highly comminuted fracture of vertebral body and cranial endplate of L6 with severe narrowing of vertebral canal. A left-sided L6 pediculectomy was performed. The cauda equina was mildly bruised. Smaller bone fragments were removed, whereas larger bone fragments were depressed ventrally. Two 1.5-mm cortical screws were inserted into pedicles of L7 and a further two 2.0-mm screws into L5 vertebral body using the pedicle-probing technique. Following exposure of underlying cancellous bone, a smartphone digital goniometer, held by a nonsterile assistant, was used to guide advancement of a blunted Kirschner wire acting as a probe according to preoperative CT-determined safe angles. Postoperative CT identified excellent vertebral column alignment with improvement in spinal cord compression and optimal placement of implants at L5 and L7 (grade 1 modified Zdichavsky). Repeat CT at 3 months postoperatively identified well-seated implants. This report highlights that use of a smartphone goniometer may be a useful adjunct to the freehand pedicle-probing technique to guide correct trajectory of the probe and may also have application in other regions of the spine.

Development and validation of a nomogram for predicting new vertebral compression fractures after percutaneous kyphoplasty in postmenopausal patients

BackgroundPostmenopausal women face a heightened risk of developing new vertebral compression fractures (NVCFs) following percutaneous kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCFs). This study aimed to develop and validate a visual nomogram model capable of accurately predicting NVCF occurrence post-PKP to optimize treatment strategies and minimize occurrence.MethodsThis retrospective study included postmenopausal women diagnosed with OVCF who underwent PKP at the Affiliated Hospital of Shandong University of Traditional Chinese Medicine between January 2016 and January 2021. Patient data, including basic information, surgical details, imaging records, and laboratory findings, were collected. The patients were categorized into two groups based on NVCF occurrence within 2 years post-PKP: the NVCF group and the non-NVCF group. Following the utilization of least absolute shrinkage and selection operator (LASSO) regression for feature selection, a nomogram was constructed. Model differentiation, calibration, and clinical applicability were evaluated using receiver operating characteristic (ROC), calibration, and decision (DCA) curve analyses.ResultsIn total, 357 patients were included in the study. LASSO regression analysis indicated that cement leakage, poor cement diffusion, and endplate fracture were independent predictors of NVCF. The nomogram demonstrated excellent predictive accuracy and clinical applicability.ConclusionsThis study used LASSO regression to identify three independent predictors of NVCF and developed a predictive model that could effectively predict NVCF occurrence in postmenopausal women. This simple prediction model can support medical decision-making and is feasible for clinical practice.

Percutaneous Juxtapedicular Cement Salvage of Failed Spinal Instrumentation? Institutional Experience and Cadaveric Biomechanical Study.

Instrumented spinal fusion constructs sometimes fail because of fatigue loading, frequently necessitating open revision surgery. Favorable outcomes after percutaneous juxtapedicular cement salvage (perc-cement salvage) of failing instrumentation have been described; however, this approach is not widely known among spine surgeons, and its biomechanical properties have not been evaluated. We report our institutional experience with perc-cement salvage and investigate the relative biomechanical strength of this technique as compared with 3 other common open revision techniques. A retrospective chart review of patients who underwent perc-cement salvage was conducted. Biomechanical characterization of revision techniques was performed in a cadaveric model of critical pedicle screw failure. Three revision cohorts involved removal and replacement of hardware: (1) screw upsizing, (2) vertebroplasty, and (3) fenestrated screw with cement augmentation. These were compared with a cohort with perc-cement salvage performed using a juxtapedicular trajectory with the failed primary screw remaining engaged in the vertebral body. Ten patients underwent perc-cement salvage from 2018 to 2022 to address screw haloing and/or endplate fracture threatening construct integrity. Pain palliation was reported by 8/10 patients. Open revision surgery was required in 4/10 patients, an average of 8.9 months after the salvage procedure (range 6.2-14.7 months). Only one revision was due to progressive hardware dislodgement. The remainder avoided open revision surgery through an average of 1.9 years of follow-up. In the cadaveric study, there were no significant differences in pedicle screw pullout strength among any of the revision cohorts. Perc-cement salvage of failing instrumentation is reasonably efficacious. The technique is biomechanically noninferior to other revision strategies that require open surgery for removal and replacement of hardware. Open revision surgery may be avoided by perc-cement salvage in select cases.

Factors Associated with Intradiscal Vacuum Phenomenon after Traumatic Thoracolumbar Fracture.

Introduction Posttraumatic kyphosis of the thoracolumbar spine is a possible cause of deterioration of activities of daily living. Thus, postoperative kyphosis is an important issue in treating traumatic thoracolumbar fractures. The intradiscal vacuum phenomenon (IVP) after a traumatic thoracolumbar fracture is considered an important predictor of severe kyphosis after implant removal. However, the associated factors are not yet clear. Methods The study included data from 94 intervertebral discs on the cephalocaudal side of 47 fractured vertebrae of 45 patients for traumatic thoracolumbar fracture due to high-energy trauma. We assessed the demographics of patients (age, sex, cause of injury, location of injured vertebra, fracture type, cephalocaudal side), imaging finding (kyphosis angle of fractured vertebra at the injury, endplate fracture on computed tomography [CT], intervertebral injury on magnetic resonance image [MRI]), and IVP on CT conducted more than 6 months after surgery. We divided the intervertebral discs into an IVP group and a non-IVP group. To identify factors associated with an IVP, univariate analysis and multivariate logistic regression analysis were conducted. Results IVP was observed in 27 (29%) of 94 intervertebral discs on CTs conducted at an average of 14.0 months postoperatively. In univariate analysis, the IVP group ( n = 27) had a significantly more cephalic side of the injured vertebra, endplate fracture on CT, and disc injury on MRI compared with the non-IVP group ( n = 67). A multivariate logistic regression analysis was conducted to identify factors associated with IVP. The cephalic side (odds ratio [OR] = 4.183, 95% confidence interval [CI] = 1.269-13.785) and endplate fracture on CT (OR = 9.564, 95% CI = 1.940-47.143) were identified as independent factors associated with IVP. Conclusions IVP was observed in 27 (29%) of 94 intervertebral discs. The cephalic side and endplate fracture on CT were identified as independent factors associated with IVP.

Evaluation of Disc and Endplate Degeneration in AO Type A Fractures Using Magnetic Resonance Imaging Analysis

Disc degeneration following trauma has been the focus of several investigations, while vertebral endplate changes have received comparatively less attention. The main aim of the study is to radiologically evaluate the prevalence of degree of degeneration of the adjacent discs and endplates following AO type A thoracolumbar fractures. We retrospectively reviewed 25 patients with AO type A injury (50 discs, and 150 endplates). The type of disc lesion adjacent to the fractured vertebra was classified based on Pfirrmann's and Oner's classifications, immediately after trauma and at 1-year follow-up. The endplate defects were assessed using the endplate scoring system (TEPS - grade 1 to 6) in T1 weighted images. The kyphosis angle and the vertebral body height were also measured. The study population consisted of 18 males (72%) and 7 females (28%) with a mean age of 38.9 ±11.3 years. Overall, 28% of fractures were type A1, 4% were type A2, 24 % were type A3 and 44% were type A4. On statistical analysis, there was a significant change in the degree of degeneration in the cranial adjacent disc based on both Oner (p=0.004) and Pfirrmann (p=0.001) classification at the end of 1-year. The morphological changes at the cranial adjacent discs at 1-year follow-up showed a strong positive correlation with superior endplate degeneration. The present study indicates that endplate fractures of vertebrae in patients with thoracolumbar burst fractures may cause disc degeneration, especially at the cranial endplate.

INVESTIGATING THE EFFECT OF LABORATORY-INDUCED DISC INJURIES ON THE BIOMECHANICAL BEHAVIOUR OF ISOLATED SPINAL DISC SPECIMENS SUBJECT TO CYCLIC LOADING

Injury of the intervertebral disc (IVD) can occur for many reasons including structural weakness due to disc degeneration. A common disc injury is herniation. A herniated nucleus can compress spinal nerves, causing pain, and nucleus depressurisation changes mechanical behaviour. Many studies have investigated in vitro IVD injuries including endplate fracture, incisions, and nucleotomy. There is, however, a lack of consensus on how the biomechanical behaviour of spinal motion segments is affected. The aim of this study was to induce defined changes to IVDs of spine specimens in vitro and apply 6 degree of freedom testing to evaluate the effect of these changes.Six porcine lumbar spinal motion segments were harvested from organically farmed pigs. Posterior structures were removed to produce isolated spinal disc specimens. Specimens were potted in Wood's metal, ensuring the midplane of the IVD remained horizontal. After potting, specimens were sprayed with 0.9% saline, wrapped in saline-soaked tissue and plastic wrap to prevent dehydration. A 400N axial preload was equilibrated for 30 minutes before testing. Specimens were tested intact and after a partial nucleotomy removing ~0.34g of nuclear material with a curette through an annular incision.Stiffness tests were performed using the University of Bath's custom 6-axis spine simulator with coordinate axes and displacement amplitudes. Tests comprised five cycles with data acquired at 100Hz. Stiffness matrices were evaluated from the last three motion cycles using the linear least squares method.Stiffness matrices for intact and nucleotomy tests were compared. No significant differences in shear, axial or torsional stiffnesses were noted. Nucleotomy caused significantly higher stiffness in lateral bending and flexion-extension with increased linearity and the load-displacement behaviour in these axes displayed no neutral zone (NZ).Induced changes were designed to replicate posterolaterally herniated discs. Unaffected shear, axial and torsional stiffnesses suggest the annulus is crucial in these axes. However, reduced ROM and NZ after nucleotomy suggests bending is most affected by herniation. Increased linearity and lack of defined NZ in these axes demonstrates herniation causes major changes to the viscoelastic behaviour of spine specimens in response to loading.

Experimentally dissociating the overuse mechanisms of endplate fracture lesions and Schmorl's node injuries using the porcine cervical spine model

BackgroundCompared to the documented overuse mechanisms of endplate fracture lesions, the cause of Schmorl's node injuries remains unknown, despite existing hypotheses. Therefore, this study aimed to examine and dissociate the overuse injury mechanisms of these spinal pathologies. MethodsForty-eight porcine cervical spinal units were included. Spinal units were randomly assigned to groups that differed by initial condition (control, sham, chemical fragility, structural void) and loading posture (flexed, neutral). Chemical fragility and structural void groups involved a verified 49% reduction in localized infra-endplate trabecular bone strength and removal of central trabecular bone, respectively. All experimental groups were exposed to cyclic compression loading that was normalized to 30% of the predicted tolerance until failure occurred. The cycles to failure were examined using a general linear model and the distribution of injury types were examined using chi-squared statistics. FindingsThe incidence of fracture lesions and Schmorl's nodes was 31(65%) and 17(35%), respectively. Schmorl's nodes were exclusive to chemical fragility and structural void groups and 88% occurred in the caudal joint endplate (p = 0.004). In contrast, 100% of control and sham spinal units sustained fracture lesions, with 100% occurring in the cranial joint endplate (p < 0.001). Spinal units tolerated 665 fewer cycles when cyclically loaded in flexed postures compared to neutral (p = 0.015). Furthermore, the chemical fragility and structural void groups tolerated 5318 fewer cycles compared to the control and sham groups (p < 0.001). InterpretationThese findings demonstrate that Schmorl's node and fracture lesion injuries can result from pre-existing differences in the structural integrity of trabecular bone supporting the central endplate.

Schmorl's nodes are associated with prevalent osteoporotic vertebral fracture and low bone mineral density: a population-based thoracic spine MRI study in older men and women.

Schmorl's node (SN) corresponds to nucleus pulposus herniation into the vertebral spongy bone with thickened trabeculae around the formed node. We hypothesize that a pathway may exist that: osteoporosis → weakened endplate → SN development ↔ endplate fracture of an osteoporotic vertebra. For osteoporotic fractures in men (MrOS) and in women (MsOS) Hong Kong studies, at 14-year follow-up, thoracic spine magnetic resonance imaging (MRI) was sampled in 270 males (mean: 82.9±3.7 years) and 150 females (mean: 81.5±4.3 years). SN and Modic change were assessed as existed or not existed. For posterior disc protrusion, ligamentum flavum ossification, and spinal canal stenosis, semi-quantitative gradings were applied. For each vertebra in women, a score of 0, 0.5, 1, 1.5, 2, 2.5, 3 was assigned for no osteoporotic vertebral fracture (OVF) or OVF of <1/5, ≥1/5-1/4, ≥1/4-1/3, ≥1/3-2/5, ≥2/5-2/3, and ≥2/3 vertebral height loss, respectively, and a summed score was calculated by summing up the scores of vertebrae T1 to T12. For men, those of minimal grade were not considered as OVF and assigned a '0' score. SN prevalence in women (55.5%) almost doubled that in men (25.9%). SN was statistically significantly correlated with lower bone mineral density (BMD) derived femoral neck T-score, while the other four spine degeneration changes were not statistically significantly correlated with the T-score. SN were statistically significantly correlated with OVF score. Subjects with SN were more likely to have OVF, with odds ratio for men of 4.32 [95% confidence interval (CI): 1.70-11.00, P=0.002] and odds ratio for women of 3.28 (95% CI: 1.23-8.74, P=0.018). Among older population, many features of SN parallel those of OVF.

Coccygeal vertebral damage in a multiparous mare following head and tail rope‐assisted recovery from general anaesthesia

SummaryAn 18‐year‐old multiparous Thoroughbred mare with a 2‐month‐old foal at foot presented for investigation of colic. A right dorsal displacement of the large colon with a retroflexion of the pelvic flexure was corrected under general anaesthesia and interventional recovery using head and tail ropes was performed. The mare made multiple attempts to stand, using the ropes for support before achieving and maintaining a standing position. The following day, marked swelling around the perineal and vulval region was noted, combined with reduced tail tone. Urination, but not defaecation, had been observed following surgery. Transrectal ultrasonography indicated formation of a haematoma adjacent and ventral to the caudal sacral and first coccygeal vertebrae. Initial radiographic evaluation was suggestive of an oblique fracture of the caudal endplate of the first coccygeal vertebra, which was confirmed on repeat radiography 7 days later. Treatment included cold compresses to reduce swelling, multimodal analgesia, dietary modification to soften faecal consistency and regular manual evacuation of the rectum to avoid impaction. The mare was discharged after 19 days hospitalisation, gradually recovered the ability to defaecate and produced a viable foal the following year without assistance.

Predictors of Vertebral Endplate Fractures after Oblique Lumbar Interbody Fusion.

Cage subsidence after oblique lumbar interbody fusion (OLIF) induces restenosis and adversely affects patient outcomes. Many studies have investigated the causes of subsidence, one of which is endplate fracture (EF). This study aimed to identify predictors of EF after OLIF. This retrospective study reviewed consecutive patients who underwent OLIF at a single institute between August 2019 and February 2022. A total of 104 patients were enrolled. The patients' demographic data and surgical details were collected through chart reviews. Radiographic variables were measured. Related variables were also analyzed using binomial logistic regression, dividing each group into those with versus without EF. EF occurred at 30 of 164 levels (18.3%), and the binary logistic analysis revealed that sex (odds ratio [OR], 11.07), inferior endplate concave depth (OR, 1.95), disc wedge angle (OR, 1.22), lumbar lordosis (OR, 1.09), pelvic incidence (OR, 1.07), sagittal vertical axis (OR, 1.02), sacral slope (OR, 0.9), L3-4 level (OR, 0.005), and L4-5 level (OR, 0.004) were significantly related to EF. OLIF in older Asian patients should be performed carefully after recognizing the high possibility of EF and confirming the factors that should be considered preoperatively.

Treatment, rehabilitation and release of a puma (Puma concolor) with sixth lumbar vertebra fracture

AbstractAn approximately 5‐month‐old, male puma (Puma concolor) was rescued after being hit by a vehicle on a highway. Radiographic examination revealed caudal endplate fracture of L6 and fissure of the vertebral arch with articular facet involvement. Conservative treatment was considered the most appropriate option due to the clinical signs, location and fracture type. The animal was confined in an enclosure that allowed limited mobility. On the 35th day after admission, a new radiographic exam showed signs similar to osteomyelitis. A 30‐day treatment with amoxicillin‐clavulanate was successful in resolving the suspected infection. At the same time, environmental enrichment was carried out by feeding living prey, which allowed the puma to be released into its natural habitat on the 79th day after admission.

Clinical efficacy of oblique lumbar interbody fusion combined with unilateral pedicle screw fixation via Wiltse approach in the treatment of lumbar spinal stenosis

To evaluate the efficacy of oblique lumbar interbody fusion combined with unilateral pedicle screw fixation via Wiltse approach in the treatment of lumbar spinal stenosis. From July 2017 to January 2019, 90 patients with lumbar spinal stenosis, including 38 males and 52 females, aged from 43 to 75 years old with an average of(59.9±8.8) years old, and were treated with oblique lumbar interbody fusion(OLIF) combined with Wiltse unilateral pedicle screw fixation. Surgical decompression and fixation was performed in 50 cases of single segment, 32 cases of double segments and 8 cases of three segments. The distribution of responsible segments included 8 cases of L2-L3, 12 cases of L3-L4 and 30 cases of L4-L5 on single segment, 10 cases of L2-L4 and 22 cases of L3-L5 on double segments, and 8 cases of L2-L5 on three segments. The operation time, blood loss and occurrence of complications were recorded, Visual analogue scale(VAS), Oswestry Disability Index(ODI) and SF-36 scale were used to evaluate clinical efficacy. Lumbar X-ray and MRI were taken at three days after operation, interverterbral space height, intervertebral foraminal height, interverterbral foraminal area, and spinal canal area were measured, and interbody fusion was evaluated according to CT at half a year after operation. All patients were followed up from 12 to 33 months, with an average of (20.2±6.6) months. Mean operation time was (103.3±35.9) min, and mean intraoperative blood loss was (70.4±17.8) ml. VAS of low back pain leg pain, and ODI decreased from 6.2±1.1, 6.1±0.9 and (59.9±4.2)% to 2.7±0.5, 2.5±0.5 and (31.3±8.8)%. SF-36 scale significantly increased from (37.2±3.1) to (54.9±6.1) at the six months postoperation(P<0.05). The intervertebral space height, intervertebral foraminal height, intervertebral foraminal area, and spinal canal area were significantly improved at 3 days after operation(P<0.05). Six months after operation, CT scan showed well fusion in 87 cases, but 3 cases with poor fusion, including 1 case of single segment, 2 cases of multi-segments. The total fusion rate was 96.7% (87/90), the single segment fusion rate was 98.0% (49/50), and the multi-segments fusion rate was 95.0%(38/40). The overall incidence of complications was 17.8%(16/90), including transient iliopsoas muscle weakness in 5 cases (5.6%), endplate fracture in 2 cases (2.2%), peritoneal injury in 1 case (1.1%), postoperative hematoma in 1 case (1.1%), adjacent segment disease in 1 case(1.1%), and fusion cage subsidence in 6 cases (6.7%). Three patients was followed up for recurrent nerve root pain and the symptoms were relieved after revision operation. All complications were relieved or disappeared in varying degrees during the follow-up period, and there were no complications such as cage displacement and screw fracture. OLIF combined with unilateral pedicle screw fixation via Wiltse approach is effective in treating lumbar spinal stenosis with minimally invasive advantages such as less trauma and less complications. Under the premise of strictly grasping the indications, this method could also achieve satisfactory clinical results in multi-segments oprations.

Does Calcium Phosphate Cement Kyphoplasty Cause Intervertebral Disk Degeneration in Adolescents?

Balloon kyphoplasty with polymethylmethacrylate (PMMA) represents the standard procedure for the treatment of thoracic and lumbar type A compression fractures. However, an increased degeneration in adjacent intervertebral disks following PMMA kyphoplasty has been demonstrated in elderly patients. Calcium phosphate cement (CPC) appears to be superior to PMMA for the intravertebral stabilization in younger patients. It remains unkown whether CPC kyphoplasty causes degeneration of adjacent disks in adolescents. Seven adolescents with thoracolumbar spine fractures underwent kyphoplasty at a mean age of 14.5 years (range 10-18). At a mean follow-up of 3.7 years (range 1 to 4.8) postoperatively, 3.0 Tesla magnetic resonance imaging (MRI) of the spine was performed to assess intervertebral disk degeneration by quantitative T2 relaxation maps and subjective ratings using modified Pfirrmann scores. A total of 56 intervertebral disks was analyzed. Initial computed tomography (CT) examinations served as basis to assess the severity of adjacent endplate injuries in terms of articular step-offs. Initial imaging detected 18 thoracolumbar vertebral body fractures of which 9 were treated with CPC kyphoplasty. Quantitative follow-up MRI revealed signs of degeneration in 10 (17.9%) of the examined 56 intervertebral disks, 7 of them adjacent to a previously fractured vertebral body. Signs of disk degeneration were significantly higher in caudal endplates with articular step-offs larger than 5 mm compared to fractured vertebral bodies without endplate step-offs. Quantitative MRI follow-ups did not suggest CPC-related intervertebral disk degradations following thoracolumbar kyphoplasty in adolescents, but indicated disk alterations correlating to adjacent endplate fracture severity.