The reduction and stabilisation of high-grade dysplastic developmental spondylolisthesis by means of modern internal fixators can correct slip, but can leave the sagittal alignment unbalanced, causing instability, e.g. in the adjacent, non-fused lumbar segments. Through analysis of the modifications of imbalance in the spine and pelvic ring due to surgical correction, this study defines the unstable zone of high-grade dysplastic developmental spondylolisthesis and proposes a simple radiographic method to identify it. 相似文献
Proximal junctional kyphosis (PJK) of the cervicothoracic spine is a deformity that can affect patients who have undergone long thoracolumbar instrumented fusion. Preoperative hyperkyphosis of the thoracic spine and changes of more than 30° in lumbar lordosis are independent risk factors for the onset of PJK.
Methods
When PJK occurs in the cervicothoracic spine, extension of the fusion with eventual application of osteotomy techniques is frequently necessary to treat symptomatic patients or in case a neurological deficit occurs. Ponte osteotomy and pedicle subtraction osteotomy (PSO) are the two most used techniques to restore a good cervicothoracic alignment, although they are still demanding procedures even for expert surgeons. In junctional fractures, a vertebral column resection can be performed to support the anterior column. Ponte osteotomy ideally restores 10° at each treated level, while PSO allows a segmental correction up to 30°–35°. Adequate preoperative planning is fundamental for outlining the correct surgery and choosing the appropriate osteotomy.
Conclusions
The aim of corrective surgery is to restore the cervicothoracic alignment, obtaining an adequate postoperative sagittal balance and decreasing the risk of further complications and new revision surgeries.
Opposed to proximal junctional kyphosis and proximal junctional failure, their distal equivalents, distal junctional kyphosis and failure (DJK/DJF) have received less attention in the literature. The aim of this article is to provide an overview of the problem of DJK–DJF in different clinical scenarios such as adolescent idiopathic scoliosis (AIS), Scheuermann’s kyphosis (SK) and adult deformity surgery and to suggest a strategy for prevention and treatment. A narrative review of the literature was conducted to identify the best evidence on the risk factors of the problem. DJK/DJF have been described as a complication of AIS, SK and adult spine deformity (ASD). For AIS and SK, the choice of a lower instrumented vertebra more cranial than the sagittal stable vertebra has shown to increase the incidence of DJK and DJF. For ASD, constructs ending with S1 pedicle screws had a higher incidence of DJK/DJF than those ending distally with S1 pedicle plus iliac screws. The proposed strategy of treatment includes restoration of normal sagittal alignment, choice of a distal fixation point stable in the sagittal, coronal and transverse planes, balancing the fusion mass over the distal fixation point and providing solid fixation at the distal end of the construct. These slides can be retrieved under Electronic Supplementary Material. 相似文献
To describe hypercomplex pedicle subtraction osteotomies (HyC-PSO) for adult spine deformity with sagittal imbalance in terms of preoperative, intraoperative and postoperative outcomes and complications.
Methods
From a prospective single centre database, patients undergoing PSO between January 2016 and May 2017 were reviewed. HyC-PSO were defined as those in patients with one of the following conditions: sagittal correction > 45° needed at a single level or at 1–3 consecutive vertebrae, more than 60° of total sagittal correction needed and PSO on segments of the spine with congenital deformities.
Results
22 patients were included, 14 had standard PSO (group A) and 8 had HyC-PSO (group B). Significant correction of lumbar lordosis (LL) and pelvic (PT) was noted in both groups (p < 0.01). Operative time was longer in HyC-PSO, 604 min compared to standard PSO, 478 min. A trend versus greater intraoperative blood loss (3837 vs 2285 ml) and greater intraoperative blood infusion (from cell saver plus homologous, 2306 vs 1280 ml) was recorded in HyC-PSO (ns). Patients in group B received significantly more blood units intra and postoperatively (8.25 vs 4.71 units, p = 0.006). Sagittal correction at the PSO level (54.7°—30° to 85°—vs 26.8°—8° to 39°—, p = 0.000) and total sagittal correction (64.5°—50 to 95°—vs 39.8°—20° to 51°—, p = 0.000) were greater in HyC-PSO. PROMs at the last available follow-up did not show significant differences between groups for any of the outcomes analyzed. Complications were similar in both groups.
Conclusion
This is the first report on hypercomplex pedicle subtraction osteotomies. Hypercomplex PSO describes a subset of clinical scenarios with increased surgical effort that can be measured as longer surgical time and greater blood transfusion requirements. Successful correction of misalignment can be achieved in this specific group of patients, and clinical results and complications profile could be similar to standard PSO procedures.
To present a classification system for vertebral body osteonecrosis (VBON) based on imaging findings and sagittal alignment and consequently to propose treatment guidelines.
Methods
Chart review and classification of imaging and clinical findings. An analysis of literature about VBON has been evaluated to conceive the classification. The current data allows to correlate radiological findings with different stages of the pathophysiological process and consequently to propose a patient-tailored treatment plan.
Results
The classification identifies 4 stages: stage 0 (theoretical phase), stage 1 (early phase), stage 2 (instability phase) and stage 3 (fixed deformity phase). Local (angular kyphosis expressed as anterior–posterior wall height ratio) and global (sagittal vertical axis and pelvic tilt) sagittal alignment are considered as complementary modifiers to tailor the most suitable treatment. Stage 1 is generally managed conservatively. Stage 2 and 3 often require different surgical approaches according to local and global sagittal alignment.
Conclusions
The classification allows a systematic staging of this disease and can help establish a proper and patient-oriented treatment plan. Further researches are advocated to fully validate the proposed classification system.
Graphical abstract
These slides can be retrieved under Electronic Supplementary Material.
