The relationship of symptomatic thoracolumbar disc herniation and Scheuermann’s disease

Scheuermann Kyphosis: Current Concepts and Management

PURPOSE OF REVIEW

Scheuermann's kyphosis (SK) is a developmental deformity of the spine that affects up to 8% of children in the US. Although, the natural progression of SK is noted to be gradual over years, severe deformity can be associated with significant morbidity. Thorough clinical examination and interpretation of relevant imaging help differentiate and confirm this diagnosis. Treatment includes both operative and nonoperative approaches. The purpose of this article is to provide an updated overview of the current theories of its pathogenesis, as well as the principles of diagnosis and treatment of SK.

RECENT FINDINGS

Although a definitive, unified theory continues to be elusive, numerous reports in the past decade provide insight into the pathophysiology of SK. These include alterations in mechanical stress and/or hormonal disturbances. Candidate genes have also been identified to be linked to the inheritance of SK. Updates to nonoperative treatment include the effectiveness of dedicated exercise programs, as well as the types and duration of orthotic treatment. Advances in surgical technique can be observed with a trend toward a posterior-only approach, with supporting evidence for careful evaluation of both the sagittal and coronal planes to determine fusion levels in order to avoid postoperative junctional pathologies. SK is an important cause of structural or rigid kyphosis. It can lead to significant morbidity in severe cases. Treatment is based on curve magnitude and symptoms. Nonoperative treatment consists of physical therapy in symptomatic patients, and bracing can be added for skeletally mature patients. Operative management can be considered in patients with large, progressive, and symptomatic deformity. Future studies can benefit from a focused investigation into patient-reported outcomes after undergoing appropriate treatment.

Scheuermann's kyphosis: update on pathophysiology and surgical treatment

Scheuermann's Kyphosis (SK) is a rigid spinal kyphosis. Several theories have been proposed concerning its pathogenesis, but it is, to this day, still unknown. It has a prevalence of 0.4-8.3% in the population with a higher incidence in females. Clinical examination with x-rays is needed to differentiate and confirm this diagnosis. Non-surgical management is reserved for smaller deformities and in skeletally immature patients, whereas surgery is recommended for higher deformities. Combined anterior and posterior approach was considered the gold standard for the surgical treatment of this disease, but there is an increasing trend toward posterior-only approaches especially with use of segmental fixation. This study reviews the pathophysiology of SK while proposing a treatment algorithm for its management.

Polg mtDNA mutator mice reveal limited involvement of vertebral bone loss in premature aging-related thoracolumbar hyperkyphosis

Background

Age-related hyperkyphosis is multifactorial and involves alterations of vertebral bone, intervertebral discs (IVD) and paraspinal muscles. The relative contribution of these tissues remains unclear. Here, we compared differences in vertebral bone microarchitecture and IVD thickness between prematurely aging mice with spinal hyperkyphosis and wild type littermates.

Methods

Thoracolumbar vertebral columns were dissected from homozygous Polg ^D257A and age-matched wild type littermates. Micro-computed tomography was performed to quantify cortical and trabecular bone parameters at anterior and posterior portions of T8-L4 vertebrae. In addition, vertebral shape, transaxial facet joint orientation and IVD thickness were quantified. Differences in anterior/posterior ratios between genotypes were compared by Student's t-test and association between vertebral bone and IVD parameters was investigated using Pearson correlation analysis.

Results

Hyperkyphotic homozygous mice displayed generalized osteopenia that was more pronounced at the posterior compared with anterior portion of thoracolumbar vertebrae. An increase in the anterior/posterior ratio of trabecular bone parameters was revealed at the thoracolumbar junction (T13-L1). Polg ^D257A displayed diffuse loss of cortical bone thickness, yet anterior/posterior ratios were unchanged. Despite generalized and regional bone loss, vertebral shape was unaffected. PolG ^D257A mice showed a 10-20 % reduction of IVD thickness at both thoracic and lumbar levels, with only minimal histopathological changes. IVD thickness was negatively correlated with anterior/posterior ratios of trabecular bone parameters, as well as with more coronally oriented facet joints, but negatively correlated with the anterior/posterior ratio of cortical bone thickness.

Conclusions

Aging-induced regional changes of vertebral trabecular and cortical bone did not lead to altered vertebral shape in Polg ^D257A mice but may indirectly cause hyperkyphosis through reduction of IVD thickness. These findings suggest a limited role for aging-induced bone loss in spinal hyperkyphosis and warrants further research on the involvement of paraspinal muscle degeneration.

Analysis of sagittal profile and radiographic parameters in symptomatic thoracolumbar disc herniation patients

BACKGROUND

Few studies describe thoracolumbar disc herniation (TLDH) as an isolated category, it is frequently classified as the lower thoracic spine or upper lumbar spine. Thus, less is known about the morphology and aetiology of TLDH compared to lumbar disc herniation (LDH). The aim of study is to investigate sagittal alignment in TLDH and analyze sagittal profile with radiographic parameters.

METHODS

Data from 70 patients diagnosed with TLDH were retrospectively reviewed. The thoracic-lumbar alignment was depicted by description of curvatures (the apex of lumbar curvature, the apex of thoracic curvature, and inflexion point of the two curvatures) and radiographic parameters from complete standing long-cassette spine radiographs. The rank sum test was utilised to compare radiographic parameter values in each subtype.

RESULTS

We found two subtypes differentiated by the apex of thoracic kyphotic curves. The sagittal profile was similar to that of the normal population in type I, presenting the apex of the thoracic kyphotic curve located in the middle thoracic spine. The well aligned thoracic-lumbar curve was disrupted in type II, presenting the apex of the thoracic kyphotic curve located in the thoracolumbar region in type II patients. Thirty-six patients were classified as type I, and 34 patients were classified as type II. The mean sagittal vertical axis, T1 pelvic angle and L1 pelvic angle were 27.9 ± 24.8°, 8.2 ± 7.3° and 6.2 ± 4.9°, respectively. There was significant difference (p < 0.001) of thoracolumbar angle between type I (14.9 ± 7.9°) and type II patients (29.1 ± 13.7°).

CONCLUSIONS

We presented two distinctive sagittal profiles in TLDH patients, and a regional kyphotic deformity with a balanced spine was validated in both subtypes. In type I patients, disc degeneration was accelerated by regional kyphosis in the thoracolumbar junction and eventually caused disc herniation. In type II patients, excessive mechanical stress was directly loaded at the top of the curve (thoracolumbar apex region) rather than being diverted by an arc as in a normal population or type I patients. Mismatch between shape and sacral slope value was observed, and better agreement was found in Type II patients.

Radiographic and clinical features of thoracic disk disease associated with myelopathy: a retrospective analysis of 257 cases

PURPOSE

To analyze the clinical and radiographic characteristics of thoracic disk disease associated with myelopathy (TDM).

METHODS

This is a retrospective clinical review of prospectively collected imaging data based at a single institute. Based on preoperative CT and MRI, we classified TDM as thoracic disk herniation (TDH), THD with ossification (THDO), TDH with posterior bony avulsions of the vertebrae (TDH with PBA), TDH with posterior vertebral osteophytes (TDH with PVO), giant thoracic osteophyte and calcific discitis with herniation (CDH). Patient characteristics and radiographic data were compared between different types of TDM.

RESULTS

Among the 257 patients included, 12.06% of patients presented with symptoms after traumatic events. The most frequent complaint at onset and preoperative was back pain (29.2%) and subjective lower limb weakness (75.5%), respectively. All TDH with PBA is distributed at the lower thoracic segments, while CDH predominantly in the middle and lower thoracic segments. TDH with PBA was more frequent in men than TDH and CDH. Compared with TDH, TDHO, and TDH with PVO, TDH with PBA was younger in surgery age, and TDH and CDH had lower preoperative JOA scores than TDH with PBA. CDH had a larger ventral occupying ratio than TDH, TDHO, and TDH with PBA.

CONCLUSIONS

The onset of TDM was generally insidious but may be triggered acutely by apparently trivial events. With a low prevalence, TDM varied clinical symptoms. Different types of TDM had various clinical features, which might indicate different pathological mechanisms.

Wedge-shaped vertebrae is a risk factor for symptomatic upper lumbar disc herniation

Background

At present, much is unknown about the etiology and pathogenesis of ULDH. However, it is interesting to note that many ULDH patients have a radiographic feature of adjacent vertebral wedge deformation. The purpose of this study is to investigate the relationship between symptomatic upper lumbar disc herniation (ULDH) and wedge-shaped vertebrae (WSV).

Methods

This was a retrospective study of 65 patients with single-level ULDH, who had undergone surgery at our medical center between January 2012 and December 2016. Clinical data including clinical and radiological evaluation results were performed.

Results

The incidence of WSV in the ULDH group (44.6%, 29/65) was more than in the lower lumbar disc herniation group (21.5%, 14/65). And there were statistically significant differences in WSV (χ² = 7.819, P = 0.005), wedging angle of the vertebrae (WAV) (t = 9.013, P < 0.001), and thoracolumbar kyphotic angle (TL) (t = 8.618, P < 0.001) between two groups. Based on multivariate logistic regression analysis, WAV (OR = 0.783, 95% CI = 0.687–0.893, P < 0.001) and TL (OR = 0.831, 95% CI = 0.746–0.925, P = 0.001) were independently associated with ULDH. The cutoff values of WAV and TL were 5.35° and 8.35°, which were significantly associated with ULDH (OR = 3.667, 95% CI = 1.588–8.466, P = 0.002).

Conclusion

The WSV is an independent risk factor for ULDH. WAV > 5.35° and TL > 8.35° were the predictors for ULDH. It should be noted that the patients with vertebral wedge deformation combined with thoracolumbar kyphosis have a higher risk of ULDH.

The Radiology of Vertebral Fractures in Childhood Osteoporosis Related to Glucocorticoid Administration

A number of unusual conditions cause decreased bone mass and density in children and these may be associated with low-trauma fractures. However, a series of reports have more recently identified that children with chronic disease sustain vertebral fractures (VFs) much more often than had been suspected. The common denominator involved is glucocorticoid (GC) administration, although other factors such as disease activity come into play. This review will focus on the imaging findings in this form of secondary osteoporosis. Spinal fractures in children have been found to correlate with back pain. At the same time, up to 2/3 of children with VFs in the GC-treated setting are asymptomatic, underscoring the importance of routine surveillance in at-risk children. Other predictors of prevalent and incident VFs include GC exposure (average daily and cumulative dose), declines in lumbar spine bone mineral density Z-scores and increases in body mass index Z-scores, as well as increases in disease activity scores. The imaging diagnosis of osteoporotic VFs in children is made differently from that in adults because immature vertebral bodies continue to ossify during growth. Thus, it is not possible to assess the vertebral end plates or periphery until late, as enchondral ossification extends centripetally within the centrum. Diagnosis, therefore, is much more dependent upon changes in shape than on loss of structural integrity, which may have a more prominent diagnostic role in adults. However, children have a unique ability to model (a growth-dependent process) and thereby reshape previously fractured vertebral bodies. If the underlying disease is successfully treated and the child has sufficient residual growth potential, this means that, on one hand, treatment of the bone disease may be of more limited duration, and, as a last recourse, the diagnosis may be apparent retrospectively.

The Michel Benoist and Robert Mulholland yearly European Spine Journal Review: a survey of the "surgical research" articles in the European Spine Journal 2014

This is a review of some 50 papers published in the European Spine Journal in the year 2014. They are selected on the basis that the author felt they were significant contributions to the spinal literature in that year. A brief precis is provided of each paper, and each is accompanied by a short discussion explaining its importance and relevance.

Radiological signs of Scheuermann disease and low back pain: retrospective categorization of 188 hospital staff members with 6-year follow-up

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To investigate the relationship between radiological signs of Scheuermann disease (SD) and low back pain (LBP) in a local population using lumbar magnetic resonance (MR) images.

SUMMARY OF BACKGROUND DATA

SD is a spinal disorder, and both its classic and atypical (lumbar) forms are associated with LBP. However, radiological signs of SD are present in 18% to 40% of the general population, in whom the clinical significance of "SD-like" spine remains largely unknown.

METHODS

This retrospective cohort study included 188 staff members from a single hospital. Participants' lumbar MR images and self-administered questionnaires concerning demographic information, LBP status, consequences, and functional limitations were collected. Participants were classified into 2 groups according to whether lumbar MR images met SD diagnostic criteria, and LBP status, consequences, and functional limitation were compared. Follow-up interviews were conducted after 6 years to compare LBP progression.

RESULTS

Thirty-four participants (18.1%) had SD-like spine. Rates of lifetime, previous 1-year, and point LBP did not significantly differ between groups. However, among participants who had ever had LBP, SD-like spine was associated with higher rates of work absence (42.1% vs. 9.5%, χ = 9.620, P = 0.002) and seeking medical care (68.4% vs. 39.2%, χ = 5.216, P = 0.022) due to LBP, as well as significantly greater intensity of the most severe LBP episode in the past 2 years (6.4 ± 2.5 vs. 4.1 ± 2.5, t = 3.564, P = 0.001). Among the 159 participants who completed the 6-year follow-up, a significantly higher proportion of people with SD-like spine reported aggravated LBP during the follow-up.

CONCLUSION

Our results suggest that in the general population, lumbar MR images of many people meet SD diagnostic criteria, and having SD-like spine seemed to be associated with the severity and progressive nature of LBP. Our findings should inspire further research in this field.

LEVEL OF EVIDENCE

3.