Vertebral fracture in elderly female patients after posterior fusion with pedicle screw fixation for degenerative lumbar pathology: a retrospective cohort study

Abstract

Background There have been only a few reports of subsequent postoperative vertebral fracture following posterior spinal instrumentation fusion, especially in elderly female patients. This study attempted to evaluate the long-term prevalence of subsequent postoperative vertebral fracture in female patients aged 70 years and older who underwent spine decompression and fusion surgery with pedicle screw fixation. Methods We retrospectively reviewed prospectively collected data from 125 patients who met our inclusion and exclusion criteria. Patients were divided into 2 groups according to age: patients aged 70 years and older (Group A) and patients aged under 70 years of age (Group B). We evaluated incidence of subsequent postoperative vertebral fractures, type and timing of vertebral fractures, preoperative bone mineral density (BMD), preoperative diagnosis, surgical procedure, number of levels fused, extension of fusion to the lumbosacral junction, and presence of a transverse fixator. Results Baseline characteristics excluding patients’ age were not statistically different between the two groups. Preoperative BMD of Group A was an average 81.7% of the young adult mean (YAM) value and that of Group B was an average 85.1% YAM value. Subsequent postoperative vertebral fractures occurred in 22 (41.5%) of 53 in Group A. On the other hand, fracture occurred in 17 (23.6%) of 72 in Group B. There were significant differences between the groups ( p = 0.02). The odds ratio for subsequent vertebral fracture was 2.4 (95% confidence interval: 1.1–5.2) in favor of Group A. Survival analysis showed that the rate of subsequent vertebral fracture was significantly higher in Group A (log-rank test, P = 0.007). Conclusions The incidence of subsequent vertebral fracture in patients aged 70 years and older was significantly higher than in patients aged under 70 years of age. In the case of pedicle screw fixation in elderly female patients, it is necessary to note the high risk of subsequent vertebral fracture despite short or non-rigid fusion. Vertebral fracture after posterior fusion surgery even for degenerative lumbar pathology could occur in more than one-third of female patients aged 70 years and older.

Biomechanical evaluation of a short-rod technique for lumbar fixation surgery

“…The fracture of the endplate is one of the common complications after lumbar fusion surgery, reported with a rate of 2.2%–14.6% ( Inoue et al, 2021 ), and osteoporotic spines and older females are recognized as being at heightened risk ( Nakahashi et al, 2019 ). This study found that stress on the endplate was significantly reduced and the stress was more evenly distributed under the action of the screw than in the intact model.…”

Proximal junctional fractures after long-segment instrumented fusion: comparisons between upper instrumented vertebrae and upper instrumented vertebrae + 1

“…Our data in both groups showed similar results: average age was over 70 years old, BMD T-score was < − 3.0, and BMI was over 25. In addition, osteoporosis caused by aging, or various comorbidities are apt to occur along with subsequent junctional vertebral fracture after long spinal instrumented fusion [ 18 ]. In the current study, CCI in the UIV group was higher than that in the UIV + 1 group (1.65 vs. 1.27), which implies that patients with more comorbidities might be more likely to develop instrumented fractures.…”

Effect of Zoledronic Acid on the Vertebral Body Bone Mineral Density After Instrumented Intervertebral Fusion in Postmenopausal Women With Osteoporosis

“…The impact of lumbar instrumented intervertebral fusion on the development of adjacent VCFs has been discussed in some studies, with evidence of an increased risk after spinal arthrodesis. 4,5,[19][20][21][22] Yang et al reported new VCFs in 150 of 1348 patients (11.1%) after posterior lumbar interbody fusion, with 108 of these (72%) being at adjacent segments. 19 Although no study has examined the relationship between new VCFs at the adjacent segment and bone loss after spinal instrumentation surgery directly, it is known that women, the elderly, and patients with osteoporosis have a specific higher incidence of new VCFs after spinal fusion, especially within the first 12 months postoperatively.…”