Vertebral Instability Research Articles

Discospondylitis, osteomyelitis and sublumbar abscessation with a pathological vertebral fracture in a dog managed by ventral omentalisation and concurrent dorsal vertebral stabilisation

AbstractThis report describes a chronic case of discospondylitis and sublumbar abscessation managed with a combination of omentalisation and vertebral stabilisation. Although there are previous reports of omentalisation in patients presenting with sublumbar abscesses, there are no documented cases of these surgeries being combined with stabilisation of a vertebral body fracture secondary to discospondylitis. This case specifically discusses an initial conservative approach and subsequent surgical intervention. A 5‐year‐old, female, neutered, cocker spaniel presented with a 2‐month history of lethargy, non‐localised pain, reluctance to move and pyrexia. Diagnostic investigations revealed a fracture of the third lumbar vertebrae, associated discospondylitis and sublumbar abscessation due to suspected foreign material. Conservative management with rest and antimicrobial therapy was initiated; however, after worsening of clinical signs, surgery was subsequently carried out. We report post‐operative follow‐up of 4 years, which revealed an overall positive outcome, with no long‐term recurrence of clinical signs or adverse effects.

Traumatic lateral spondyloptosis and lateraloptosis with partial improvement through posterior surgical approach: a review based on a case report

Introduction. Spondyloptosis or grade V of spondylolisthesis, spinal injury that involve 100 % mobilization of the vertebral body, is rare to find. Lateraloptosis, displacement of vertebral bodies, is even more rare a catastrophic.The aim of this study to introduce readers to this rare form of traumatic lumbar spine injury as well as to review current available therapeutic approaches.Case report. A 22-year-old male was admitted to the emergency room due to a fall from a moving truck. Physical examination revealed neurological deficit in the lower extremities, with muscle strength 0/5, and an ASIA B classification. Computed tomography study showed a complete lateroloptosis at the L3 –L4 level. The patient is admitted to the operating room for surgical treatment through a posterior approach. Successful arthrodesis and spinal alignment are achieved. Immediate postoperative period, showed no complications and the patient’s neurological function in the lower extremities was classified as ASIA C. In the posterior follow-up, the patient maintains the motor neurological function and recover the autonomic control of bladder function. With mild disability according to the Barthel Index of 90 points.Discussion. of the traumatic spinal injuries, spondyloptosis is the most infrequent and occurs secondary to high-energy mechanisms. It presents an incidence of complete neurological deficit in 80 % of patients. The objectives in surgical treatment are decompression of neurovascular structures, reduction of fracture dislocation to improve alignment in the sagittal and coronal plane, and instrumentation that allows stability. The posterior surgical approach offers advantages over the anterior approach. In the posterior approach, the facet joints can be manipulated more safely, decompress the nerve roots and the dural sac more easily, as well as less operating time and greater care of vascular structures such as the iliac vessels.Conclusion. Complex traumatic spinal injuries are associated with irreversible neurological damage. Achieving spinal stability and alignment allows optimizing physical therapy and rehabilitation for greater recovery. Severe spinal injuries, especially lateroptosis, are difficult to treat by surgical approach, however, the main objective is vertebral stabilization to allow physical therapy and early rehabilitation.

The Impact of the Lowest Instrumented Vertebra on the Correction of the Minor Curve During Selective Fusion in Patients With Adolescent Idiopathic Scoliosis.

Retrospective single-center data analysis. The aim of this investigation was to give advises for choosing the LIV in selective fusion to reach the best correction of the minor curve and sagittal profile. Scoliotic curves can be classified as structural or nonstructural. If selective fusion is performed, the nonstructural curves are not instrumented. The choice of the lowest instrumented vertebra (LIV) and the impact of different levels of the LIV on the correction of the minor curve in the frontal profile and on the sagittal balance is under debate. Forty-seven consecutive patients treated by posterior instrumented fusion were included in this retrospective investigation. Impact of the level of the LIV with regard to distance to end vertebra (EV), to the stable vertebra (StV), to the sagittal infliction point (IP), and to the apex of the lumbar lordosis on the correction of the minor curve was analyzed. Distance of LIV to EV was significant with regard to correction of the minor curve if it was more than 5 levels (P<0.001). Distance of LIV to StV was significant with regard to correction of the minor curve if it was more than 4 levels (P<0.01). Distance of LIV to IP was significant with regard to correction of the minor curve if it was more than 2 levels (P<0.01). Choosing a LIV that was more than 2 levels higher or lower than the sagittal infliction point showed a significantly higher correction of the minor curve. We therefore recommend to keep that distance when LIV is chosen.

Surgical management of congenital cervical spondylolytic spondylolisthesis: illustrative case.

Congenital cervical spondylolytic spondylolisthesis is a rare and complex disorder of the cervical spine. Surgical treatment is reserved for those symptomatic patients who do not improve with conservative management. A 34-year-old man presented with bilateral C7 radiculopathy for the past 6 months. Magnetic resonance imaging of the cervical spine revealed grade II C6-7 spondylolisthesis. Computed tomography showed the presence of spondyloarthritis, bilateral pedicle dysplasia, bilateral isthmic defect, and spinous process schisis. Dynamic radiographs showed no signs of vertebral instability. Dynamic magnetic resonance imaging showed kinking of the spinal cord over the fulcrum of C6-7 kyphosis during flexion, with no signs of myelopathy. The patient underwent C6-7 anterior fusion surgery. His symptoms improved postoperatively, with a 2-month computed tomography scan showing initial bony bridging. The absence of evident instability on radiography does not always correspond to the absence of actual functional compression of neurological structures. Spinal misalignment, muscle dysfunction, and kyphotic deformity with kinking of the spinal cord and stretching of the nerve roots may also contribute to the development of symptoms. In this setting, dynamic magnetic resonance imaging can be extremely useful. Single-level anterior fusion surgery without posterior fixation can achieve solid fusion and improve the clinical conditions of patients. https://thejns.org/doi/10.3171/CASE24174.

Exploring factors affecting activities of daily living in patients with osteoporotic vertebral fractures managed conservatively: a post-hoc analysis of a prospective cohort study.

A post-hoc analysis of a prospective cohort study. This study aimed to identify factors at the time of injury associated with declining activities of daily living (ADLs) in the chronic phase of osteoporotic vertebral fractures (OVFs) managed conservatively. Although a conservative approach is the treatment of choice for OVFs, ADLs do not improve or eventually decrease in some cases. However, the risk factors for ADL decline after the occurrence of OVFs, particularly the difference between those with or without initial bed rest, are unknown. A total of 224 consecutive patients with OVFs aged ≥65 years who received treatment within 2 weeks after the occurrence of injury were enrolled. The patients were followed up for 6 months thereafter. The criteria for evaluating the degree of independence were applied to evaluate ADLs. Multivariable analysis with a logistic regression model was performed to evaluate the risk factors for ADL decline. In total, 49/224 patients (21.9%) showed a decline in ADLs. Of these, 23/116 patients (19.8%) in the rest group and 26/108 patients (24.1%) in the no-rest group experienced a decline in ADLs. In the logistic regression analyses, a diffuse low signal on T2- weighted magnetic resonance imaging (MRI) (odds ratio, 5.78; 95% confidence interval, 2.09-16.0; p=0.0007) and vertebral instability (odds ratio, 3.89; 95% confidence interval, 1.32-11.4; p=0.0135) were identified as independent factors in the rest and no-rest groups, respectively. In patients with acute OVFs, a diffuse low signal on T2-weighted MRI and severe vertebral instability were independently associated with ADL decline in patients treated with and without initial bed rest, respectively.

Quantification of metallic artifact on CT associated with titanium pedicle screws.

In dogs undergoing vertebral column stabilization, post-operative computed tomography (CT) evaluates implant placement. The impact on the interpretation of metallic artifact associated with titanium implants in dogs remains to be established. Our objective was to quantify metallic artifact on CT associated with titanium pedicle screws. The study design included an in vitro model and a retrospective review of 11 dogs with vertebral column stabilization. Twenty four titanium pedicle screws (6 each: 2.0 mm, 2.7 mm, 3.5 mm, and 4.5 mm) were inserted into a 20% ballistic gel, and CT scan of the construct was performed. Three blinded raters used a bone window to measure the maximum width (effective size) of each screw, one rater measured effective size using an ultrawide window and 45 titanium pedicle screws (3×2.0 mm, 5×2.7 mm, 30×3.5 mm, and 7×4.5 mm) in 11 clinical cases. Effective size measurements were compared to actual screw sizes. The effective size was 26.9-43.8%, 9.2-18.5%, and 21.1-30.5% larger than the actual size for the in vitro system (bone window), in vitro system (ultrawide window), and clinical cases, respectively. The mean gross difference for the in vitro measurements varied by implant size (p < 0.001) and was positively correlated with implant size (r = 0.846), but the mean percentage difference was negatively correlated with implant size (p < 0.001). Overestimation was larger for the in vitro model bone window compared to the ultrawide window (p < 0.001) and clinical cases (p = 0.001). Metallic artifact associated with titanium pedicle screws on CT resulted in an overestimation of screw size. This information might aid in the interpretation of implant placement on post-operative imaging.

Biomechanical study between percutaneous vertebroplasty combined with cement pedicle plasty improves vertebral biomechanical stability: A finite element analysis

ObjectiveTo investigate the biomechanical effects of percutaneous vertebroplasty combined with cement pedicle plasty (PVCPP) on the unstable osteoporotic vertebral fractures (OVFs) through finite element (FE) analysis. The study compares the biomechanical stability of finite element models between percutaneous vertebroplasty (PVP) and percutaneous vertebroplasty combined with cement pedicle plasty.MethodsTwo patients with unstable OVFs underwent computed tomography (CT) examination at the thoracolumbar vertebral body levels, respectively. The CT images were reconstructed into three-dimensional finite element models to simulate stress conditions across six dimensions and to evaluate the vertebral von Mises stress before and after bone cement reinforcement.ResultsThe study found that stress distribution differed between groups mainly at the pedicle base. In the surgical vertebral bodies, the maximum stress in the PVP group decreased during flexion and left bending, while it increased in other states. In the PVCPP group, all maximum stresses decreased. In the inferior vertebral bodies, the maximum stress in the PVP group generally increased, while it decreased in the PVCPP group. In the superior vertebral bodies, postoperatively, the maximum stress in the PVP group generally increased, while it almost remained unchanged in the PVCPP group. PVP group had higher cement stress and displacement.ConclusionPVCPP is an effective treatment method for patients with unstable OVFs. It can quickly relieve pain and enhance the stability of the three columns, thereby reducing the risk of some complications.

Bipolar hybrid posterior instrumentation tecnique for the correction of Scheuermann's kyphosis.

Scheuermann´s kyphosis (SK) is the most common cause of painful and progressive structural hyperkyphosis in adolescents. Surgical treatment should be considered in cases of refractory pain or progressive deformities. We present the clinical and radiological results obtained using a bipolar, hybrid posterior instrumentation tecnique. We analysed 12 males and 6 females, with mean age of 15.8years. Minimum follow-up was 2years. We used transverse process hooks at the cranial level and polyaxial screws for the remaining levels. We did not instrument the periapical segment. We used the sagittal stable vertebra (SSV) as the lower instrumented vertebra (LIV) in most cases, the "barely touched SSV" if the above disc space is lordotic. The mean preoperative kyphosis was 73.6º, mean postoperative kyphosis 44.7º, and mean correction of 28.9º (p = 0.0002). The mean reduction in lumbar lordosis (LL) was 8.9º (p = 0.0018). There were no significant differences in the spinopelvic parameters or sagittal balance. The mean number of instrumented levels was 8.9. Type II osteotomies were necessary in only three patients. Three patients had a cranial sagittal angle greater than 10°, all of them asymptomatic. Postoperatively, all patients had VAS scores less than 2 and SRS-22 scores greater than 4. Hybrid bipolar posterior instrumentation offers adequate curve correction, less operative time, implant density, bleeding, material protrusion and risk of spinal cord injury, leaving a large periapical bed for graft supply. We propose to measure the flexibility of the curve in MRI. In flexible curves (those that correct at least 20% in the supine decubitus position), wide facetectomies offer adequate correction of the deformity.

Usefulness of modified S-line for upper instrumented vertebra selection in adolescent idiopathic scoliosis Lenke type 1C curve.

Determine the effect of using the modified S-line vertebra (MSLV) as the upper instrumented vertebra (UIV) on postoperative trunk balance, L4 tilt, and clinical outcomes in selective thoracic fusion (STF) for adolescent idiopathic scoliosis (AIS) Lenke type 1C curve. Twenty-eight consecutive patients (all female; mean age: 15.4±2.0 years) with AIS Lenke type 1C curve were retrospectively enrolled. Primary outcome measures were coronal balance (absolute distance between C7 and the center of the sacral vertical line), L4 tilt, and Scoliosis Research Society (SRS)-22r scores at 2 years postoperatively. The group with the MSLV at the UIV was designated as the MSLV group (18 patients), and the group with the MSLV proximal (12 patients) or distal (4 patients) to the UIV was defined as the non-MSLV group. We observed no significant differences between the groups regarding age, LIV and stable vertebra positioning, or preoperative X-ray parameters. Postoperative coronal balance was significantly better in the MSLV group (0.39±0.08 vs. 1.34±0.22 cm; P.

Perioperative epidural catheter analgesia as a component of a multimodal analgesic approach in a dog with thoracic hemivertebrae and kyphosis undergoing thoracic vertebral stabilisation

AbstractA 4‐year‐old, male, neutered French bulldog weighing 13.5 kg presented with urinary and faecal incontinence, progressive, non‐painful paraparesis and pelvic limb proprioceptive ataxia. Magnetic resonance imaging revealed a T12 constrictive myelopathy in association with multiple thoracic vertebral malformations, and mildly impinging thoracic intervertebral disc protrusions. Additionally, there was a sacral axial defect and degenerative lumbosacral stenosis. Surgical treatment comprised bilateral dorsal vertebral stabilisation of T9–T13. This case report summarises the peri‐anaesthetic management, which included an ‘in‐plane’ ultrasound‐guided placement of an epidural catheter at the level of L3–L4 and advancement cranially to T12 as a component of a multimodal analgesic regimen. Following the cessation of postoperative epidural bupivacaine administration, the patient remained comfortable without requiring rescue analgesia, and was discharged within 24 hours of surgery. At the latest recheck 5 months after surgery, the dog's neurological status remained static. This technique and application remain unexplored in existing veterinary literature.

Projections of Single-level and Multilevel Spinal Instrumentation Procedure Volume and Associated Costs for Medicare Patients to 2050.

Instrumented spinal fusions can be used in the treatment of vertebral fractures, spinal instability, and scoliosis or kyphosis. Construct-level selection has notable implications on postoperative recovery, alignment, and mobility. This study sought to project future trends in the implementation rates and associated costs of single-level versus multilevel instrumentation procedures in US Medicare patients aged older than 65 years in the United States. Data were acquired from the Centers for Medicare & Medicaid Services from January 1, 2000, to December 31, 2019. Procedure costs and counts were abstracted using Current Procedural Terminology codes to identify spinal level involvement. The Prophet machine learning algorithm was used, using a Bayesian Inference framework, to generate point forecasts for 2020 to 2050 and 95% forecast intervals (FIs). Sensitivity analyses were done by comparing projections from linear, log-linear, Poisson and negative-binomial, and autoregressive integrated moving average models. Costs were adjusted for inflation using the 2019 US Bureau of Labor Statistics' Consumer Price Index. Between 2000 and 2019, the annual spinal instrumentation volume increased by 776% (from 7,342 to 64,350 cases) for single level, by 329% (from 20,319 to 87,253 cases) for two-four levels, by 1049% (from 1,218 to 14,000 cases) for five-seven levels, and by 739% (from 193 to 1,620 cases) for eight-twelve levels (P < 0.0001). The inflation-adjusted reimbursement for single-level instrumentation procedures decreased 45.6% from $1,148.15 to $788.62 between 2000 and 2019, which is markedly lower than for other prevalent orthopaedic procedures: total shoulder arthroplasty (-23.1%), total hip arthroplasty (-39.2%), and total knee arthroplasty (-42.4%). By 2050, the number of single-level spinal instrumentation procedures performed yearly is projected to be 124,061 (95% FI, 87,027 to 142,907), with associated costs of $93,900,672 (95% FI, $80,281,788 to $108,220,932). The number of single-level instrumentation procedures is projected to double by 2050, while the number of two-four level procedures will double by 2040. These projections offer a measurable basis for resource allocation and procedural distribution.

Comparison of osteoanabolic agents (teriparatide and romosozumab) with bisphosphonates in prevention of subsequent vertebral fractures in patients treated for osteoporotic vertebral fracture for 12 months: An observational cohort study

IntroductionDomino osteoporotic vertebral fracture (OVF) is as a subsequent fracture that develops within 3 months before the initial OVF heals. There is limited evidence regarding the efficacy of osteoanabolic agents on its treatment. This study evaluated the effects of bisphosphonates and anabolic agents teriparatide and romosozumab on subsequent domino OVF. MethodsThis was post hoc analysis of a prospective, multicenter, observational study conducted across 8 hospitals, enrolling 144 patients with conservatively treated OVF, grouped into patients receiving bisphosphonate (BP, n = 55), teriparatide (TPTD, n = 62), and romosozumab (Romo, n = 27). The primary outcome was the incidence of subsequent OVF at 3 and 12 months, whereas the secondary outcomes included the incidence of pseudoarthrosis and progression of vertebral collapse (VC). Pseudoarthrosis was classified as stable or unstable based on vertebral instability. ResultsThe use of osteoanabolic agents did not reduce the incidence of subsequent OVF at 3 and 12 months. There were no significant differences in the background data or type of conservative treatment among the three groups. However, the TPTD and Romo groups had significantly lower rates of unstable pseudarthrosis (p = 0.03). Additionally, there were no significant differences in VC progression between groups, but it tended to be higher in the BP group than the TPTD and Romo group (p = 0.07). ConclusionOsteoanabolic agents were beneficial in reducing unstable pseudoarthrosis, but were not more effective than bisphosphonates in the development of subsequent domino OVF. A more comprehensive approach to the treatment of osteoporosis is needed to prevent domino OVFs.

A low-cost phantom design for evaluating spine SABR calculations in the presence of prosthetic vertebral stabilization.

Dose-perturbation characteristics are important to consider during the calculation of radiation therapy protocols for patients who are going to receive high doses that would reach the tolerance limits of the spinal cord [1]. Several studies have investigated dose perturbations introduced by metal implants in close proximity to spine SABR treatments [2-7]. However, there is a lack of work assessing this effect using the RayStation TPS [8]. We present an initial design for a low-cost phantom to evaluate spine stereotactic ablative radiotherapy (SABR) in the presence of prosthetic vertebral stabilization. The phantom is modular, allowing the prosthetic at the centre of the phantom to be removed by exchanging the central block. It also includes space to insert ion chamber and film. The agreement of the RayStation TPS (v8.0B) collapsed cone convolution (CCC) calculation and measurement was determined for phantom versions with and without prosthetic. There was little to no change in the agreement between the measured and calculated dose when introducing metallic hardware. This suggests that our Raystation-based SABR planning approach for patients with spinal hardware meets clinical expectations. Departments without access to anthropomorphic phantoms may find this design useful but should test their phantom design in typical clinical settings to ensure it is robust to real world situations.

Lowest instrumented vertebrae in early onset scoliosis: is there a role for a more selective approach?

PurposeThis purpose of this study was to assess the impact of patient and implant characteristics on LIV selection in ambulatory children with EOS and to assess the relationship between the touched vertebrae (TV), the last substantially touched vertebrae (LSTV), the stable vertebrae (SV), the sagittal stable vertebrae (SSV), and the LIV.MethodsA multicenter pediatric spine database was queried for patients ages 2–10 years treated by growth friendly instrumentation with at least 2-year follow up. The relationship between the LIV and preoperative spinal height, curve magnitude, and implant type were assessed. The relationships between the TV, LSTV, SV, SSV, and the LIV were also evaluated.ResultsOverall, 281 patients met inclusion criteria. The LIV was at L3 or below in most patients with a lumbar LIV: L1 (9.2%), L2 (20.2%), L3 (40.9%), L4 (29.5%). Smaller T1 − T12 length was associated with more caudal LIV selection (p = 0.001). Larger curve magnitudes were similarly associated with more caudal LIV selection (p = < 0.0001). Implant type was not associated with LIV selection (p = 0.32) including MCGR actuator length (p = 0.829). The LIV was caudal to the TV in 78% of patients with a TV at L2 or above compared to only 17% of patients with a TV at L3 or below (p < 0.0001).ConclusionsMost EOS patients have an LIV of L3 or below and display TV–LIV and LSTV–LIV incongruence. These findings suggest that at the end of treatment, EOS patients rarely have the potential for selective thoracic fusion. Further work is necessary to assess the potential for a more selective approach to LIV selection in EOS.Level of evidenceIII.

Finite element analysis of different pedicle screw internal fixations for first lumbar vertebral fracture in different sports conditions.

Lumbar fractures are the most common spinal injuries, and surgery is required for severe fracture. This study aimed to investigate the variations in motion and stress in varying states of activity after minimally invasive and traditional open pedicle screw placement for L1 vertebral fracture stabilization. We studied a male volunteer (26 years old) with no history of chronic back pain or lumbar spine trauma. We used the finite element method for this investigation. Using finite element software, we created a three-dimensional model of L1 vertebral compression fracture. We also constructed models for four percutaneous pedicle screws spanning the fractured vertebra and four screws traversing the damaged vertebra with transverse fixation. In all three-dimensional movement directions, the open pedicle fixation system experienced maximum stress higher than its percutaneous counterpart. With axial spinal rotation, von Mises stress on the traditional open pedicle screw was considerably lower than that with percutaneous pedicle fixation, but peak stress was elevated at the transverse connection. Traditional open pedicle fixation displayed less maximum displacement than percutaneous pedicle internal fixation. During axial spinal movements, high peak stress is observed at the transverse connection. Patients should avoid excessive axial rotation of the spine during recovery.

Возможности использования комбинированной техники тракции и стабилизации шейного отдела позвоночного столба у собак при лечении цервикальной спондиломиелопатии

In the article the results of treatment of Wobbler syndrome in 19 dogs are presented. The surgical technique of discofenestration, traction of the vertebral bodies and stabilization with using of interbody cage, transvertebral screw and two reconstructive LP-platies were used. Most of dog’s owners considered results of surgical treatment as excellent and good.

Articular arthrodesis with the facet wedge technique for the treatment of unstable lumbar degenerative disease and associated conditions: A retrospective study of 96 patients

BackgroundLumbar articular fusion with the facet wedge (FW) technique is gaining increasing interest among surgeons for the treatment of vertebral instability due to its limited invasiveness and ease of use. Studies on cadavers have reported biomechanical properties similar to pedicle screws. Yet, the evidence supporting their use is still limited and moreover focused only on spinal degenerative disease. Methods96 cases of lumbar articular fusion with the FW techniques performed at 3 different centers between 2014 and 2022 were retrospectively analyzed based on the specific surgical indications: 1) degenerative spondylolisthesis/unstable lumbar stenosis; 2) synovial cysts; 3) adjacent segment disease (ASD). Medical records were reviewed to identify rates of complications and measures of functional outcome (ODI, low back pain VAS and modified Macnab scale) were collected both at baseline and at the follow-up visits. Wilcoxon signed-rank test was adopted to test for significant functional improvements. ResultsSignificative clinical improvements were observed from baseline to follow-up regarding ODI and VAS scores. Overall rate of moderate and severe complications (according to Landriel–Ibañez scale) was 7.9%. Only 3.4% of patients with degenerative disease developed ASD requiring reoperations. Only one case of radicular deficit and one of device mobilization were reported. 2/4 cases of synovial cysts treated with unilateral fusions developed contralateral complications. 9 out of 16 (56.25%) patients who underwent long-term postoperative CT scans presented adequate degree of articular fusion. ConclusionFW technique is easy, safe, and effective. Its low rate of complications justifies its use for cases of mild lumbar instability.

Short-Term Risk Factors for Distal Junctional Kyphosis after Spinal Reconstruction Surgery in Patients with Osteoporotic Vertebrae.

Level 3 retrospective cohort case-control study. This study aimed to investigate the risk factors for distal junctional kyphosis (DJK) caused by osteoporotic vertebral fractures following spinal reconstruction surgery, with a focus on the sagittal stable vertebra. Despite the rarity of reports on DJK in this setting, DJK was reported to reduce when the lower instrumented vertebra (LIV) was extended to the sagittal stable vertebra in the posterior corrective fixation for Scheuermann's disease. This study included 46 patients who underwent spinal reconstruction surgery for thoracolumbar osteoporotic vertebral fractures and kyphosis and were followed up for 1 year postoperatively. DJK was defined as an advanced kyphosis angle >10° between the LIV and one lower vertebra. The patients were divided into groups with and without DJK. The risk factors of the two groups, such as patient background, surgery-related factors, radiographic parameters, and clinical outcomes, were analyzed. The DJK and non-DJK groups included 14 and 32 patients, respectively, without significant differences in patient background. Those with instability in the distal adjacent LIV disc had a significantly higher risk of DJK occurrence (28.6% vs. 3.2%, p=0.027). DJK occurrence significantly increased in those with the sagittal stable vertebra not included in the fixation range (57.1% vs. 18.8%, p=0.020). Other preoperative radiographic parameters were not significantly different. Instability in the distal adjacent LIV disc (adjusted odds ratio, 14.50; p=0.029) and the exclusion of the sagittal stable vertebra from the fixation range (adjusted odds ratio, 5.29; p=0.020) were significant risk factors for DJK occurrence. Regarding spinal reconstruction surgery in patients with osteoporotic vertebral fractures, instability in the distal adjacent LIV disc and the exclusion of the sagittal stable vertebra from the fixation range were risk factors for DJK occurrence in the short term.

Distal Junctional Failures in Degenerative Thoracolumbar Hyperkyphosis.

Degenerative thoracolumbar hyperkyphosis (DTH) is a disease that negatively affects individual health and requires surgical intervention, yet the ideal surgical approach and complications, especially distal junctional failures (DJF), remain poorly understood. This study aims to investigate DJF in DTH and to identify the risk factors for DJF so that we can improve surgical decision-making, and advance our knowledge in the field of spinal surgery to enhance patient outcomes. This study retrospectively reviewed 78 cases (late osteoporotic vertebral compression fracture [OVCF], 51; Scheuermann's kyphosis [SK], 17; and degenerative disc diseases [DDD], 10) who underwent corrective surgery in our institute from 2008 to 2019. Clinical outcomes were assessed using health-related quality of life (HRQOL) measures, including the visual analogue scale (VAS) scores for back and leg pain, the Oswestry disability index (ODI), and the Japanese Orthopaedic Association (JOA) scoring system. Multiple radiographic parameters, such as global kyphosis (GK) and thoracolumbar kyphosis (TLK), were assessed to determine radiographic outcomes. Multivariate logistic regression analysis was employed to identify the risk factors associated with DJF. HRQOL improved, and GK, TLK decreased at the final follow-up, with a correction rate of 67.7% and 68.5%, respectively. DJF was found in 13 of 78 cases (16.7%), two cases had wedging in the disc (L3-4) below the instrumentation, one case had a fracture of the lowest instrumented vertebrae (LIV), one case had osteoporotic fracture below the fixation, nine cases had pull-out or loosening of the screws at the LIV and three cases (23.1%) required revision surgery. The DJF group had older age, lower computed tomography Hounsfield unit (CT HU), longer follow-up, more blood loss, greater preoperative sagittal vertical axis (SVA), and poorer postoperative JOA and VAS scores (back). The change in TLK level was larger in the non-DJF group. Post-sagittal stable vertebrae (SSV) moved cranially compared with pre-SSV. Age, CT HU, length of follow-up, estimated blood loss, and preoperative SVA were independent risk factors for DJF. We recommend fixation of the two vertebrae below the apex vertebrae for DTH to minimize surgical trauma.

Surgical management of cranial thoracolumbar stenosis and concurrent kyphoscoliosis in a dog by dorsal vertebral stabilisation using low‐profile three‐dimensional printed patient‐specific drill guides

AbstractThe study described the clinical and imaging findings, treatment and outcome for a British bulldog with cranial thoracic vertebral canal stenosis and thoracolumbar kyphoscoliosis. Data on clinical presentation, diagnostic imaging, surgical procedure, complications and outcome were evaluated. Multiple thoracic vertebral body and dorsal arch malformations were detected by computed tomography and magnetic resonance imaging, resulting in spinal cord compression due to vertebral canal stenosis at T5–T6 and T9–T10, as well as kyphoscoliosis. Surgical vertebral stabilisation between T2 and T10 was performed by using a novel design of unilateral three‐dimensional printed patient‐specific drill guides, to preserve the dorsal spinous processes. Neurological signs had completely resolved 2 months after surgery. Follow‐up examination and computed tomography scan 15 months postoperatively revealed normal neurological status, implant stability and no progression of kyphoscoliosis. This novel design of unilateral three‐dimensional printed patient‐specific drill guides allowed dorsal thoracic vertebral stabilisation without resection of dorsal spinous processes and multiple‐level stabilisation.