Research progress in the evaluation of adult spinal deformities associated with osteoporosis and prevention of proximal junctional kyphosis or failure after corrective surgery
10.3760/cma.j.cn121113-20240130-00075
- VernacularTitle:合并骨质疏松症的成人脊柱畸形骨质量的评估与术后近端交界性后凸或失败预防的研究进展
- Author:
Dawei SONG
1
;
Junjie NIU
;
Jinning WANG
;
Qi YAN
;
Xiao SUN
;
Huilin YANG
;
Jun ZOU
Author Information
1. 苏州大学附属第一医院骨科，苏州 215006
- Keywords:
Osteoporosis;
Bone density;
Spinal fusion;
Adult spinal deformity;
Proximal junctional kyphosis/failure;
Hounsfield unit
- From:
Chinese Journal of Orthopaedics
2024;44(11):778-786
- CountryChina
- Language:Chinese
-
Abstract:
With the aging population, the increasing incidence of adult spinal deformity (ASD) associated with osteoporosis (OP) presents new challenges for evaluation and management. Although reasonable and standardized non-surgical treatment remains the first choice in the early stages of this disease, surgical treatment is necessary for patients with severe deformities and significant symptoms to achieve further improvement. Proximal junctional kyphosis/failure (PJK/PJF) is one of the most serious postoperative complications of ASD. Careful and comprehensive preoperative evaluation of bone quality and body sagittal alignment is crucial for the successful implementation of the operation. The Hounsfield unit (HU) based on CT imaging and the vertebral bone quality (VBQ) score based on MRI have proven to be reliable, effective, simple, and widely used in evaluating local vertebral bone quality in recent years. For the evaluation and prediction of PJF after ASD, the bone quality of the upper instrumented vertebra (UIV) can be assessed using HU values to identify high-risk patients and implement preventive measures. The VBQ score is predictive of the incidence of PJK/PJF in patients undergoing ASD surgery, with a high VBQ score being one of the risk factors for PJK/PJF after ASD correction. Patients with high VBQ scores can delay surgery and use anti-osteoporosis drugs before surgery to reduce the occurrence of PJK/PJF. Meanwhile, reasonable and personalized recovery parameters of ASD patients' sagittal sequence can help balance the benefits of efficacy and complications, maximizing the overall benefits. The prevention of PJK/PJF is challenging due to the stress gap between the internal fixation area and the original unfixed tissue area in the postoperative proximal junctional area, which is increasingly significant in OP patients. It is necessary to improve the fixation strength and bone riveting strength of the proximal junction area properly and to gradually decrease the fixed strength in the proximal junctional area to achieve a smooth transition of stress and avoid stress concentration resulting in failure. Relevant strategies include: 1. Enhanced proximal junction fixation, such as vertebral cement-enhanced pedicle screw fixation. 2. Strategies to cushion the stress in the proximal junction, such as Topping-off technology, which includes laminar/transverse hooks, dynamic rods, multi-segment stabilization screws, and multiple ligament-binding straps. 3. Minimally invasive technology can better protect the soft tissues such as the posterior ligament complex and muscles, reduce iatrogenic injury, and thus reduce the incidence of PJK/PJF. Currently, there are many controversies about the optimal treatment for ASD with OP, but the goal is to achieve maximum efficacy while minimizing complications. Additionally, attention should be paid to reasonable and standard anti-osteoporosis treatment in the perioperative period. This paper summarizes the relevant studies used to evaluate PJK/PJF after ASD in patients with OP and reviews the research progress on PJK/PJF prevention strategies, providing reference and ideas for reducing postoperative proximal junctional complications in adult spinal deformity patients with osteoporosis.
