Association between non-traumatic vertebral fractures and adjacent discs degeneration: a cross-sectional study and literature review

Endplate fractures with subtle structural damage in impact loaded flexed ovine lumbar segments: a potential initiator of disc degeneration

PURPOSE

To (a) investigate patterns of structural damage in flexed, healthy ovine lumbar motion segments subjected to controlled impact loading approximating a low energy traumatic fall; and (b) determine the relative risk of herniation, endplate failure and other subtle modes of structural disruption as potential mechanical initiators of disc degeneration.

METHODS

Twenty-three healthy ovine lumbar motion segments were flexed 7° and then impact loaded by dropping a weight of 4.3 kg from a height of 0.8 m. Each sample was macroscopically assessed externally for herniations and then sagittally bisected to assess internal structural damage.

RESULTS

Fifteen segments suffered endplate failure, 7 herniated, and 1 suffered both an endplate fracture and herniation. Thirteen segments had a major fracture of the superior endplate and 8 of these also contained subtle damage in the anterior annulus and/or inferior vertebra. Overall, both herniated and endplate fractured samples indicated an oblique mode of failure tending from posterior-superior to anterior-inferior. Other forms of subtle tissue damage were observed across all visible regions of the disc, these coexisting with the major modes of failure.

CONCLUSION

Flexed ovine lumbar motion segments subjected to impact loading approximating a low energy traumatic fall, are more likely to fail via endplate fracture accompanied by more subtle structural damage in the disc and/or adjacent vertebra. Failure by disc herniation was less common. The subtle, co-occurring, multi-component failure modes add to our recognition of the complexity of these injuries, and the potential role they might play in the initiation and development of the degenerative cascade in the intervertebral disc.

Association of vertebral fractures with worsening degenerative changes of the spine: a longitudinal study

Vertebral compression fractures (VFs) and spinal degeneration are both common causes of back pain, particularly in older adults. Previous cross-sectional studies have shown a potential association between these entities, but there is limited evidence on the role of VFs in spinal degeneration. In this longitudinal study, we evaluated the association between prevalent VFs and the subsequent progression of facet joint osteoarthritis (FJOA) and intervertebral disc height narrowing (DHN), using data from the Framingham Heart Study Offspring and Third Generation Multi-Detector Computed Tomography study. Summary indices representing the total burden of each spinal parameter (VFs, DHN, and FJOA) were calculated for each individual. We hypothesized that prevalent VFs are associated with worsening spinal degeneration. Three hundred and seventy (31%) of 1197 participants had a baseline (prevalent) VF. The change in summary index of DHN over the follow-up period was significantly higher in those with vs without prevalent VF (difference in change in DHN 0.38, 95% CI 0.18 to 0.59, p<.001), but the change in summary index of FJOA was similar between those with and without prevalent VF. However, once adjusted for age, sex, cohort, smoking status, BMI, and baseline DHN, the change in summary index of DHN did not differ by prevalent VF status. There was a modestly higher change in the FJOA summary index in those with prevalent VFs compared to those without in the fully adjusted model (difference in change in FJOA 0.62, 95% CI -0.01 to 1.24, p = .054), driven primarily by those with severe (grade 3) VF (difference in change in FJOA 4.48, 95% CI 1.99-6.97). Moreover, there was greater change in the summary index of FJOA with increasing severity of prevalent VF (linear trend p = .005). Beyond the established morbidity and mortality associated with VFs, our study suggests that VFs may also lead to worsening spine osteoarthritis.

Progression of vertebral deformity of prevalent vertebral fractures in the elderly: a population-based study

BACKGROUND

Little is known about the progression pattern of vertebral deformities in elderly patients with prevalent vertebral fractures. This population-based cohort study investigated the incidence, progression pattern, and risk factors of vertebral deformity in prevalent vertebral fractures over a finite period of four years in a population-based cohort study.

METHODS

A total of 224 inhabitants of a typical mountain village underwent medical examinations every second year from 1997 to 2009, and each participant was followed up for four years. The extent (mild, moderate, severe) and type (wedge, biconcave, crush) of prevalent vertebral fractures on spinal radiographs were evaluated using the Genant semi-quantitative method. Of these participants, 116 with prevalent vertebral fractures at baseline (32 men and 84 women; mean age: 70.0 years) were included in this study. The progression patterns of the 187 vertebral fractures with mild and moderate deformities (except severe deformity) were evaluated. Logistic regression analysis was used to identify the risk factors associated with deformity progression.

RESULTS

The progression of vertebral deformities was identified in 13.4% (25 vertebral fractures) of the total 187 prevalent (mild and moderate) vertebral fracture deformities over four years. Among the three deformity types, the prevalence of deformity progression was significantly lower in wedge-type vertebral fractures (P < 0.05). Age and number of prevalent vertebral fractures per participant were independent risk factors associated with the progression of prevalent vertebral deformities.

CONCLUSION

This study clarified the natural history of the progression pattern of vertebral deformities in radiographic prevalent vertebral fractures in elderly individuals. Multiple vertebral fractures in the elderly present a risk for the progression of vertebral deformities.

Fatty Degeneration of the Autochthonous Muscles Is Significantly Associated with Incidental Non-Traumatic Vertebral Body Fractures of the Lower Thoracic Spine in Elderly Patients

PURPOSE

We investigated loco-regional degenerative changes' association with incidentally found non-traumatic vertebral body fractures of the lower thoracic and lumbar spine in older patients. Methods: The patient collective included patients in the age range of 50 to 90 years. Vertebral bodies from T7 to L5 were included. Vertebral body fractures were classified according to Genant. The following loco-regional osseous and extra-osseous degenerative changes were included: osteochondrosis, spondylarthritis, facet joint asymmetries, spondylolisthesis, scoliosis as well as fatty degeneration and asymmetry of the autochthonous back muscles. Patients with traumatic and tumor-related vertebral body fractures were excluded. Non-traumatic fractures of the lower thoracic and lumbar spine were evaluated separately. The Mann-Whitney U-test was used, and relative risks (RRs) were calculated for statistics. Pearson's correlations (Rs) were used to correlate grades of degenerative changes and fracture severities. Results: 105 patients were included. Fatty deposits in the autochthonous muscles of the lower thoracic and the lumbar spine were associated with non-traumatic vertebral body fractures in the lower thoracic spine (p = 0.005, RR = 4.92). In contrast, muscle fatness of the autochthonous muscles was not a risk factor for lumbar spine fractures (p = 0.157, RR = 2.04). Additionally, we found a moderate correlation between fatty degeneration of the autochthonous muscles and the severity of fractures in the lower thoracic spine (RR = 0.34, p < 0.001). The other degenerative changes did not present any significant difference or correlation between the evaluated groups. Conclusions: Fatty degeneration of the autochthonous spinal musculature is associated with incidentally found non-traumatic fractures of the lower thoracic spine.

A Prospective Evaluation of Percutaneous Vertebroplasty in Osteoporotic Vertebral Compression Fracture Patients

Background Osteoporotic vertebral compression fracture (OVCF) is a common problem in old age, which causes incapacitating pain and leads to significant disability, morbidity, and mortality. Percutaneous vertebroplasty (PVP), a minimally invasive procedure, results in immediate pain relief with decreased morbidity. The primary aim of this study was to evaluate the quality of life (QOL), as denoted by the Roland-Morris Disability Questionnaire (RMDQ) score. In contrast, the secondary aims were determining pain relief using the 11-point Numeric Pain Rating Scale (NPRS) and vertebral height restoration and wedge angle measurements after PVP. Methodology This prospective, longitudinal, interventional study on the efficacy of PVP was conducted among patients with low back pain due to osteoporotic vertebral collapse in a tertiary care institute. Patients with OVCF were managed by PVP and followed at one week, one month, three months, and six months for improvement in QOL by the RMDQ score and pain relief using the NPRS. The pre and post-vertebroplasty wedge angle and vertebral height (anterior, middle, and posterior columns) at one week and six months were also compared by pre and post-vertebroplasty lateral view skiagrams. Results A total of 24 patients were included in this study based on the inclusion and exclusion criteria. The demographic data were comparable. The RMDQ score showed a statistically significant difference in post-PVP at one week (p = 0.044), one month (p = 0.031), three months (p = 0.022), and six months (p = 0.018). There was a statistically significant difference in the NPRS at six months compared to the pre-PVP status, showing drastic pain relief in patients after PVP. The mean wedge angle (20.5 ± 2.07) measurement was reduced with a statistically significant increase in anterior body height restoration from pre-PVP to six months. There was no significant change in height at the middle and posterior columns compared to the pre-PVP height. Conclusions PVP is an effective, safe, minimally invasive pain and spine intervention for OVCFs with improved QOL and restoration of vertebral height.

Lumbar osteoporotic fractures develop in segments with less degenerated discs which then become more degenerated

PURPOSE

Our aim was to study the influence of segmental variations in intervertebral disc degeneration on the location of acute osteoporotic compression fractures and to investigate chronic effect of such fractures on adjacent discs.

METHODS

This retrospective study included 83 patients (69 females; mean ± SD age: 72.3 ± 14.0 years) with osteoporotic vertebral fractures. Using lumbar MRI, two neuroradiologists evaluated 498 lumbar vertebral segments for the presence and acuity of fractures and graded adjacent intervertebral disc degeneration on Pfirrmann's scale. Absolute and relative (to average patient-specific degeneration grade) segmental degeneration grades were compared against the presence and chronicity of vertebral fractures for all segments and for upper (T12-L2) and lower (L3-L5) subgroups. Intergroup analysis was conducted using Mann-Whitney U tests, with p value of  < .05 considered significant.

RESULTS

Fractures involved 149/498 (29.9%; 15.1% acute) vertebral segments, majority (61.1%) involving T12-L2 segments. Segments with acute fractures had significantly lower degeneration grades (mean ± SD: absolute: 2.72 ± 0.62; relative: 0.91 ± 0.17) than those with no (absolute: 3.03 ± 0.79, p = 0.003; relative: 0.99 ± 0.16, p < 0.001) or chronic fractures (absolute: 3.03 ± 0.62, p = 0.003; relative: 1.02 ± 0.16, p < 0.001). Degeneration grades were higher in the lower lumbar spine (p < 0.001) in the absence of fractures, but comparable to upper spine for segments with acute or chronic fractures (p = 0.28 and 0.56, respectively).

CONCLUSIONS

Osteoporotic vertebral fractures favour segments with lower burden of disc degeneration, but likely contribute to subsequent worsening of adjacent disc degeneration.