Aims. The aim of this study was to investigate the impact of the level of upper instrumented vertebra (UIV) in frail patients undergoing surgery for adult spine deformity (ASD). Methods. Patients with adult spinal deformity who had undergone T9-to-pelvis fusion were stratified using the ASD-Modified Frailty Index into not frail, frail, and severely frail categories. ASD was defined as at least one of: scoliosis ≥ 20°, sagittal vertical axis (SVA) ≥ 5 cm, or pelvic tilt ≥ 25°. Means comparisons tests were used to assess differences between both groups. Logistic regression analyses were used to analyze associations between frailty categories, UIV, and outcomes. Results. A total of 477 patients were included (mean age 60.3 years (SD 14.9), mean BMI 27.5 kg/m. 2. (SD 5.8), mean Charlson Comorbidity Index (CCI) 1.67 (SD 1.66)). Overall, 74% of patients were female (n = 353), and 49.6% of patients were not frail (237), 35.4% frail (n = 169), and 15% severely frail (n = 71). At baseline, differences in age, BMI, CCI, and deformity were significant (all p = 0.001). Overall, 15.5% of patients (n = 74) had experienced mechanical complications by two years (8.1% not frail (n = 36), 15.1% frail (n = 26), and 16.3% severely frail (n = 12); p = 0.013). Reoperations also differed between groups (20.2% (n = 48) vs 23.3% (n = 39) vs 32.6% (n = 23); p = 0.011). Controlling for osteoporosis, baseline deformity, and degree of correction (by sagittal age-adjusted score (SAAS) matching), frail and severely frail patients were more likely to experience mechanical complications if they had heart failure (odds ratio (OR) 6.6 (95% CI 1.6 to 26.7); p = 0.008), depression (OR 5.1 (95% CI 1.1 to 25.7); p = 0.048), or cancer (OR 1.5 (95% CI 1.1 to 1.4); p = 0.004). Frail and severely frail patients experienced higher rates of mechanical complication than ‘not frail’ patients at two years (19% (n = 45) vs 11.9% (n = 29); p = 0.003). When controlling for baseline deformity and degree of correction in severely frail and frail patients, severely frail patients were less likely to experience clinically relevant proximal junctional kyphosis or failure or mechanical complications by two years, if they had a more proximal UIV. Conclusion. Frail patients are at risk of a poor outcome after surgery for adult spinal deformity due to their comorbidities. Although a definitively prescriptive upper instrumented vertebra remains elusive, these patients appear to be at greater risk for a poor outcome if the upper instrumented vertebra is sited more distally. Cite this article: Bone Joint J 2024;106-B(11):1342–1347

Introduction. Transosseous flexion-distraction injuries of the spine typically require surgical intervention by stabilizing the fractured vertebra during healing with a pedicle-screw-rod constructs. As healing is taking place the load shifts from the implant back to the spine. Monitoring the load-induced deflection of the rods over time would allow quantifiable postoperative assessment of healing progress without the need for radiation exposure or frequent hospital visits. This approach, previously demonstrated to be effective in assessing fracture healing in long bones and monitoring posterolateral spinal fusion in sheep, is now being investigated for its potential in evaluating lumbar vertebra transosseous fracture healing. Method. Six human cadaveric spines were instrumented with pedicle-screws and rods spanning L3 vertebra. The spine was loaded in Flexion-Extension (FE), Lateral-Bending (LB) and Axial-Rotation (AR) with an intact L3 vertebra (representing a healed vertebra) and after transosseous disruption, creating an AO type B1 fracture. The implant load on the rod was measured using an implantable strain sensor (Monitor) on one rod and on the contralateral rod by a strain gauge to validate the Monitor's measurements. In parallel the range of motion (ROM) was assessed. Result. The ROM increased significantly in all directions in the fractured model (p≤0.049). The Monitor measured a significant increase in implant load in FE (p=0.002) and LB (p=0.045), however, not in AR. The strain gauge detected an increased implant load not only in FE (p=0.001) and LB (p=0.016), but also in AR (p=0.047). The highest strain signal was found during LB for both, the Monitor, and the strain gauge. Conclusion. After a complete transosseous disruption of L3 vertebra the load on the implants was significantly higher than in the intact respectively healed state. Innovative implantable sensors could be used to monitor those changes allowing the assessment of healing progression based on quantifiable data rather than CT-imaging

1. A case of vertebra plana (Calvé) is described and serial radiographs throughout the course of the disease are presented. 2. The initial radiographs showed a vertebra of normal depth which collapsed to a thin disc in fifteen days. Since the symptoms had begun twelve days before the first examination the total time taken to reach this stage was twenty-seven days. 3. The literature has been reviewed for evidence of the underlying pathology of vertebra plana. In the case described biopsy of the affected vertebral body was not carried out, and thus the nature of the underlying change could not be determined

To investigate and compare the biomechanical characteristics of Bipedicular versus Unipedicular Vertebroplasty in cadaveric vertebra. Cadaveric single level vertebra were used to evaluate Bipedicular versus Unipedicular Vertebroplasty as an intervention for vertebral compression fractures. Cadaveric vertebra were assigned to two arms: Arm A simulated a wedge fracture followed by bipedicular cement augmentation; Arm B simulated a wedge fracture followed by unipedicular cement augmentation. Micro-CT imaging was performed to assess vertebral dimension, cement fill volumes and bone mineral density. All augmented specimens were then compressed under a static eccentric flexion load to failure. Pre and post augmentation failure load and stiffness were used to compare the two groups. Results suggest, when compared with actual failure strength, that the product of bone mineral density and endplate surface area gave a good prediction of failure strength for specimens in both arms. The mean cement volume fill of augmented vertebral bodies was 22.8% ± 7.21%. The bipedicular group showed a reduction in stiffness but an increase in post augmentation failure load of 1.09. The unipedicular group also showed a reduction in stiffness but showed a much greater increase in post augmentation failure load of 1.68. Preliminary data from this study suggests there is a significant reduction in stiffness following both bipedicular and unipedicular vertebroplasty. There is a significant increase in failure load post augmentation in the unipedicular group

The lumbar spine consists of a mobile segment of 5 vertebrae, which are located between the relatively immobile segments of the thoracic and sacral segments. The bodies are wider and have shorter and heavier pedicles, and the transverse processes project somewhat more laterally and ventrally than other spinal segments. The laminae are shorter vertically than are the bodies and are bridged by strong ligaments. The spinous processes are broader and stronger than are those in the thoracic and cervical spine. Internal fixation as an adjunct to spinal fusion has become increasingly popular in recent years. Stainless steel or titanium plates or rods are longitudinally anchored to the spine by hooks or pedicle screws. Powerful forces can be applied to the spine through these implants to correct deformity. Implants provide immediate rigid spinal immobilization, which allows for early patient mobilization, and provides a more optimal environment for bone graft incorporation. Numerous clinical and experimental studies demonstrate higher fusion rates in patients with rigid internal fixation than in controls without instrumentation. Although various implants are available, pedicle fixation systems are the most commonly used implant type in the lumbosacral spine. The large size of the lumbar pedicles minimizes the number of instrumented motion segments required to achieve adequate stabilization. Many authors have reported loss of postoperative deformity correction after transpedicular screw fixation, ranging from 2.5 degrees to 7.1 degrees. The general preference is to stabilize the fractured vertebra by fusing one level above and one level below. With this technique, the rate of loss of correction is high. At our institution, we routinely stabilize the unstable thoracolumbar fractures by fusing one level above and one level below. In addition, we put screws into the pedicle(s) of fractured vertebrae. The reason for this is the following:. To correct the deformed body of the fractured vertebra for better load sharing. To make use of the pedicles of the fractured vertebra for superior rotatory stabilization. To avoid the need for the inclusion of additional levels, thereby preserving motion segments. To avoid the need for possible anterior spinal fusion and instrumentation. To obtain a better correction of a kyphotic deformity. Plain radiographs were analysed post operatively and compared for reduction of the fracture fragments and correction of kyphotic deformity to pre-operative films. 74 Patients were admitted with thoracolumbar spine fractures to our hospital. 48 Patients were surgically treated, and 34 patients were available for follow up. We found that inserting the pedicle screws into the fractured vertebra provided good stabilization for very unstable fractures. No loss of correction was seen in the follow up x-rays. We conclude that including the fractured vertebra into the fracture fixation device not only provides better fracture reduction, but also gives improved rotatory stability

Purpose: The purpose of this work was to study the reliability and the precision of a lumber vertebra reconstruction method using images obtained from a 3D statistical model and two calibrated radiograms. The technique is designed for surgical approach to the lumbar spine and implantation of osteosynthesis material using enhanced-reality technology. Material and methods: A lumbar vertebra was reconstructed on several specimens using images issuing from a 3D statistical model and two calibrated radiograms. The images obtained from the model of this lumbar vertebra to be reconstructed constituted the preoperative images. Intra-operative images corresponded to two calibrated radiograms acquired with a fluoroscope using advanced technology (silicium receptor). The model was equipped with reflecting patches which can be detected in space using a 3D optical system. Correspondence between the 3D statistical model and the two calibrated radiograms was achieved with appropriate software. Navigation views were displayed on the screen to guide surgical tools at the vertebral level. Pedicular screws were implanted into several anatomic specimens to evaluate the reliability and precision of the system. The exact position of the implanted screws was established with computed tomography. Results: This system demonstrated its reliability and precision for the reconstruction of a lumbar vertebra from a 3D statistical model and two calibrated radiograms. All the implanted screws were perfectly positioned in the pedicles. Precision was to the order of 1 mm. Discussion: This method is a passive system not requiring intraoperative intervention. Reconstruction of a lumbar vertebra from a preoperative 3D statistical model and two intra-operative calibrated radiograms avoids the need to identify anatomic landmarks and/or surface points on the vertebra to be reconstructed. The level of precision is very similar to that obtained with CT-based systems. Preoperative CT is not needed for navigation. Conclusion: With this system, new generation fluoroscopic equipment should appear in the operating room, allowing acquisition of successive calibrated images. The digital data could then be matched with statistical anatomic data, avoiding the need for preoperative imaging (CT or MRI). Progressive introduction of intra-operative ultrasound to replace the calibrated radiograms should open a new approach for percutaneous surgery of the lumbar spine

Percutaneous vertebroplasty (PVP) is an emerging interventional technique for treatment of vertebral compression fractures. Bone cement is introduced to mechanically augment fracture and pain relief is almost immediate. Recent clinical and biomechanical studies have outlined the phenomenon of fractures occurring in adjacent vertebrae following PVP [. 1. ,. 2. ]. It is widely believed that rigid cement augmentation may cause a shift in the normal loading pattern of the spine thereby resulting in adjacent fractures. However, very few studies have attempted to quantify this effect [. 3. ]. Most biomechanical studies adopt a single vertebral body as a model for PVP analysis. With this approach it is not possible to determine the effect of load distribution on adjacent structures. Where multi-segment vertebrae have been used there is little documentation of the fracture characteristics produced or their repeatability. The purpose of this study was to develop a 3-vertebra model for the biomechanical analysis of PVP. The particular focus was on developing a robust technique for generating repeatable level of fracture severity from specimen to specimen. An alignment device was developed to fit into standard materials testing machine, which allowed constant axial compression without causing lateral bending or flexion-extension of the specimen’s ends. Porcine 3-segment specimens (T8-L2) were mechanically compressed to failure at a rate of 5mm/min applied vertically at a distance of 35% to the anterior edge of the specimen’s anterior-posterior length. During the test load-displacement data was displayed in real time on a PC. In order to generate uniform fractures, a protocol was devised in which the specimens were compressed for a further 6mm after initial yield point. After the initial fracture the segments were augmented with 3ml of PMMA cement injected through each pedicle and then recompressed. The fracture characteristics generated under these conditions were analysed using quantitative microcomputer tomogragy (μCT). μCT images showed that fractures were generated in the central vertebra, with some propagation towards adjacent vertebra. The results support the use of a 3-segment specimen as a better representation for PVP analysis. The method will enables the load shift and fracture progression on either side of the augmented vertebra to be observed, thereby providing a more complete picture of load-bearing kinetics. Secondly, the middle, augmented motion segment remains unconstrained by platens and cement impressions; hence its anatomical boundary conditions are less compromised. Although longer segments have been shown to be more anatomically appropriate, it is difficult to apply physiologic levels of load without causing the specimen to buckle. We were able to minimise buckling effect by incorporating an alignment device to position the specimen without constraint. Given the preceding observations, the concepts of 3-segment specimen in PVP biomechanical tests provides a suitable compromise in choosing an appropriate clinical setting for in-vitro testing of biological spine specimens

1. A forty-nine-year-old man had a chondrosarcoma arising from the body of the seventh thoracic vertebra. The tumour protruded into the mediastinum and also into the spinal canal where it displaced the spinal cord. 2. At operation all the seventh thoracic vertebra and parts of the sixth and eighth were removed together with the tumour. The thoracic spine was reconstructed by inserting two iliac bone-blocks between the cut bodies of the sixth and eighth vertebrae and by wiring two strong "A. O." plates to the transverse processes of the third to the sixth and the eighth to the tenth vertebrae. 3. The patient was nursed in a plaster-of-Paris bed for three and a half months. 4. One year and three months after operation, the patient was walking and well, with no signs of recurrence or metastasis. Radiographs showed that a block-vertebra had been created from the iliac grafts and the two cut vertebrae

We have studied fracture-dislocation of the fifth lumbar vertebra in seven patients and reviewed 50 previously reported cases. Based on this information, we have classified the injury into five types: type 1, unilateral lumbosacral facet-dislocation with or without facet fracture; type 2, bilateral lumbosacral facet-dislocation with or without facet fracture; type 3, unilateral lumbosacral facet-dislocation and contralateral lumbosacral facet fracture; type 4, dislocation of the body of L5 with bilateral fracture of the pars interarticularis; and type 5, dislocation of the body of L5 with fracture of the body and/or pedicle, with or without injury of the lamina and/or facet. Conservative treatment of fracture-dislocation of L5 is generally not effective because the lesion is fundamentally unstable. Planning of the operation should be made on the basis of the various types of injury

Considerable numbers of authors have reported the change in periprothetic bone mineral density (BMD) after hip arthroplasty. However, there have been few reports concerning the BMD in the lumbar vertebra, especially for dysplastic hips. Since 1998, we have been measuring the BMD mineral density for 2016 patients by DXA (Dual-energy X-Ray Absorptionmetry method). Among them, we evaluated the BMD in 66 postmenopausal patients with the single side primary arthroplasty, with five years or more follow-up, and also aged 60 or more. We used a DXA densitometer (DPX-IQ, GE Healthcare, Madison, WI, USA). The diagnosis at the surgery was dysplastic osteoarthritis in all patients. The average age at the surgery was 66 (60–81). All patients were female. No patients had the systematic diseases which contributed to the secondary osteoporosis. No patients had received the pharmacotherapy for osteoporosis in the whole therapeutic process. The bed rest was seven from two days after the surgery (different by the operation date). The average follow-up was 7.0 (five to ten) years. The average BMD in the lumbar vertebra before the surgery was 0.996 (0.612 to 1.712) g/cm2. The BMD was 0.971 (0.637 to 1.402) at six month postoperatively, 0.972 (0.552 to 1.740) at one year, 1.004 (0.573 to 1.733) at two years, 1.032 (0.633 to 1.670) at three years, 1.035(0.724 to 1.688) at four years, 1.031 (0.564 to 1.679) at five years, 1.027 (0.734 to 1.647) at six years, 1.042 (0.589 to 1.389) at seven years. At the final follow-up, the BMD was 1.054 (0.589 to 1.647). In 53 patients (80%), the density at the final follow-up increased in comparison to that before the surgery. In 27 patients (41%), the density once decreased six month postoperatively. The density increased at 3 years (t=−1.919, p=0.030), four years (t=−2.523, p=0.015), five years (t=−2.381, p=0.021), seven years (t=−2.822, p=0,007), and at the final-follow-up (−4.076, p= 0.000) in comparison to that before the surgery. The activity of the patients was evaluated by the hip score. The average score was 54.5 (21 to 76) before the surgery. The average score was 88.0 (66 to 100) and increased at the final follow-up in comparison to that before the surgery (t=−13.04, p 0.000). Some authors (eg. Bergström I, 2008, Espar I, 2008, etc.) have pointed out that the appropriate activity may increase the bone density. Presumed from the literatures, the increase of activity after the arthroplasty may have increased the BMD, though the direct correlation was not obvious between the BMD and the amount of hip score (at the final follow-up: r=0.005, p=0.972) in this study

We studied 23 patients with spondylolysis of the fifth lumbar vertebra (L5) and 20 with spondylolytic spondylolisthesis at this level. All were more than 40 years of age. The transverse processes at L5 were significantly wider in the former group than in the latter. We also dissected 56 cadavers to study the morphological relationship between the transverse process of L5 and the iliolumbar ligament, and found that the wider transverse process is associated with increased width of the posterior band of the iliolumbar ligament. If a patient with pars defects has wide transverse processes at L5, the lumbosacral junction may be stabilised by wide posterior bands of the iliolumbar ligament and the fifth lumbar vertebra by the ligament, preventing anterior displacement

1. A case is reported of a benign osteoblastoma of the body of the second thoracic vertebra causing paraplegia in a woman aged twenty-six. 2. The tumour was resected, apparently entirely, through a costo-transversectomy approach, and the paraplegia resolved almost completely. 3. Five and a half years later symptoms recurred, due to a recurrence in the form of a large, partly calcified tumour in the left upper thorax which was resected in toto via a transpleural approach. 4. The considerable histological differences between the original tumour and the recurrence are discussed

Study Design: A retrospective review of the functional outcome of neurologically intact patients with burst fractures of the first lumbar vertebra. Objective: To assess the functional outcome of patients treated either surgically or conservatively following burst fractures of L1. Methods: A retrospective review of 38 neurologically intact patients with burst fractures of L1 was performed. Follow-up clinical evaluation was obtained from 26 patients, eleven of whom were treated surgically and fifteen of whom were managed conservatively. Patients were assessed with regard to pain, employment status, ability to partake in recreational activities and their overall satisfaction with treatment. Radiographic evaluation of anterior body compression and vertebral kyphosis was performed at the time of injury. Computed tomography scanning of spinal canal compromise was also recorded at the time of injury. Subsequent recordings of vertebral kyphosis were assessed at the time of remobilisation and at 3-month follow-up evaluation. Results: Mean follow-up time for the 26 patients was 43.02 months. At final clinical follow-up of the fifteen patients managed conservatively, 6 patients (40%) had little or no pain; 12 patients (80%) had returned to work with 6 (40%) stating that they had little or no restrictions in their ability to work; 8 patients (53%) had returned to the same level of recreational activity as prior to their injury with 7 (47%) stating they had little or no restrictions in their ability to participate in recreational activities. One patient (9%) reported being very dissatisfied with the operative treatment of their spine fracture. No correlation was found between kyphotic deformity, extent of canal compromise and clinical outcome. Conclusions: Non-operative management of burst fractures of the first lumbar vertebra is a very safe and effective method of treatment. It reduces hospitalisation time and avoids the costs and risk of surgery. Patients return to the functional activities of daily living quickly and have a better clinical outcome when compared with operative management

Purpose: There is scant literature with respect to reproducibility in radiological measurements of vertebral morphology. The purpose was to determine the reliability of measurement of various parameters of vertebral morphology in idiopathic scoliosis. Method: Ten patients with AIS were investigated with standardised low dose multi-slice helical CT. Axial reconstructions in the plane of the T8 (apical) vertebra were performed prone, as per Jamieson et al (2008). Antero-posterior (AP) canal diameter, left and right pedicle width, canal width, left and right mid-point to medial pedicle length, left and right pedicle length, and cord length, left and right transverse angles, and left and right canal area were measured by our spine surgeons and spine surgery fellow. Statistical analysis for intra-class coefficients (ICC) for intra and inter observer reliability was then performed. Results: Intra-observer reliability was excellent, with a mean ICC score of 0.930 (range 0.608–0.996), across all fourteen variables. Inter-observer reliability was very good with a mean ICC score of 0.890 (range 0.360–0.987), across all variables. There was poor inter-observer reliability for measurement of the transverse pedicle angles (0.360 – 0.446). The intra-observer reliability for transverse pedicle angles, whilst good (0.608–0.861), was worse than any of the other intra-observer reliabilities. Conclusion: We demonstrate excellent intra, and inter observer reliability for measurement of apical vertebrae morphology in AIS. This tool can be utilized in the further study of pedicle dysplasia. Measurement of transverse pedicle angle was less reliable than any of the other measurement variables. A standardised measurement of the morphology of vertebral canal, pedicles and vertebral body morphology is reliable both within individual observers, and across a group of observers. A standardised measure for further investigation has been validated which will enable study of the evolution of pedicle dysplasia over time. This will lead to a better understanding of the etiology of pedicle dysplasia in scoliosis

Total removal of the third thoracic vertebra and partial removal of the second and fourth vertebrae together with partial lung resection were successfully performed in a twenty-two-year-old woman with a large, radioresistant, giant-cell tumour which completely surrounded the spinal cord and extended over the left lung. On admission, the patient was in her third episode of paraplegia, the two previous episodes having been temporarily relieved after decompression of the spinal cord by laminectomy and partial removal of the tumour. Three and a half months after operation she was discharged walking without support and with normal sphincter control. Two years later she is free of symptoms and the neurological status is practically normal. Clinical and radiological examinations show no signs of recurrence of the tumour

Aims

The aim of this study was to assess the ability of morphological spinal parameters to predict the outcome of bracing in patients with adolescent idiopathic scoliosis (AIS) and to establish a novel supine correction index (SCI) for guiding bracing treatment.

Objective: To present the clinical features, radiological findings and differential diagnosis of this rare benign condition. Design: Melorheostosis (Leri’s Disease) is a rare mesenchymal dysplasia commonly exhibiting hyperostosis on the internal and external aspect of tubular bones in a sclerodermal distribution. It usually occurs in the limbs, frequently crosses joints and there is often ossification in local soft tissues. Presenting features may include pain, restricted joint movement and skin thickening. It very rarely affects the spine and its cause is unknown. Subject: A 40-year-old female presented with insidious onset of mild mid thoracic back pain. There was no history of trauma and she had no past medical or family history. She underwent a six-month course of physiotherapy but this failed to help her symptoms. She developed a small lump over the area of pain and her GP arranged an X-Ray. This showed an irregular area of high attenuation over the right side of the tenth thoracic vertebra. A CT demonstrated a “dripping candle wax” appearance of densely calcified cortical bone undulating over the right side of the body and posterior elements of T10. The ossification crossed the synovial zygoapophyseal joint but not the intervertebral disc and a diagnosis of melorheostosis was suggested. MRI supported the CT findings and confirmed the presence of a soft tissue lesion over the dorsal process of T10. A bone scan verified the solitary nature of the lesion and showed widening of the right side of the body of T10 with increased focal uptake. All blood and urine investigations were normal. Results: The patient underwent an open biopsy to obtain sufficient tissue for histological diagnosis and confirm that the lesion was benign in nature. It was felt that the dense ossification of the lesion would make percutaneous biopsy difficult. The most important differentials to exclude were an osteosclerotic bone metastasis and osteosarcoma. Other differential diagnoses were a parosteal osteoma, a burnt out osteoblastoma and a giant bone island. The soft tissue histology showed a necrotic fibrocartilagenous mass. The bone samples required prolonged decalcification prior to cutting and were composed of compact cortical bone similar to the appearances seen in ivory osteoma and also consistent with melorheostosis. This pathological pattern and the radiological finding of cortical compact bone crossing a synovial joint confirms the diagnosis of melorheostosis. Conclusions: Spinal melorheostosis is a rare condition. The diagnosis should be considered in the differential of atypical osteosclerotic lesions of vertebrae. Adequate histological sampling is essential in order to exclude malignancy

Compressive fracture of osteoporotic vertebrae has been one of the most important health problems in aged societies because severely injured spin might be a reason of bedridden for elderly people. Osteoporosis has been widely assessed by averaged bone mineral density of vertebrae measured using DEXA, however, BMD sometimes does not reflect the strength of vertebrae. CT imaged based finite element method (CT-FEM) has been applied to evaluate the strength of vertebrae based on the biomechanics theory and approved by a part of the highly advanced medical treatment in Japan. In the present study, compressive strength of more than 100 vertebrae were evaluated using CT-FEM, and the correlation between BMD and the strength was thoroughly investigated. It was found that some vertebrae with high BMD could have low strength which may cause fracture easily. Thus, a controversial point of the BMD based diagnosis of osteoporosis was clearly indicated. In this invited talk, some basic theories of CT-FEM and fracture assessment and some key results from the recent study will be presented.

This report describes a nine-year-old girl with a spondylolisthesis of the C2 vertebra allowing 14 mm of slip. Her father had very similar vertebral anomalies.