Degenerative disc disease: genotyping, MR imaging and phenotyping

A Case-control Study of Major Genetic Predisposition Risk Alleles in Developing DDD in the Northeast US Population: Effects of Gene-gene Interactions

STUDY DESIGN

A case-control study of risk alleles for degenerative disc disease (DDD) using magnetic resonance (MR) imaging for phenotyping.

OBJECTIVE

We aim to provide the first statistically adequately powered study of the relationship between the presence of common risk alleles and occurrence of DDD in Eastern US population.

SUMMARY OF BACKGROUND DATA

Many genetic predisposing factors have been identified in elevating the risk of DDD, including common variants in VDR, COL1A1, AGC1, COL9A2/3 genes.

METHODS

We utilized the Mass General Brigham (MGB) Biobank in which subjects' Medical Record is linked with genotyped data from single-nucleotide polymorphism (SNP) arrays. Subjects with lumbosacral spine MR imaging studies were used to construct the Cases cohort; the Biobank's Controls cohort was used as the Control cohort. Odds ratios (OR) and False-discovery-rate (FDR) q values from multiple-hypotheses-testing corrections were used to assess the likelihood of DDD given occurrence of the listed DDD risk alleles.

RESULTS

Four-hundred-fourteen subjects (mean age = 64, range = 27 to 94) were Cases and 925 Controls (mean age = 46, range = 21-61). A systematic search has identified 25 SNPs in 18 genes in the SNP arrays. At univariate level, rs1544410 in VDR was significantly associated with DDD for male subjects (odds ratio [OR] = 0.594, P = 0.011). After adjustment for all significant variants and demographics, three predictor variables had a significant association with the outcome, age (OR = 1.130, q < 0.0001), rs143383 (OR = 1.951, q = 0.056), and rs3737821 (OR = 2.701, q = 0.069). A novel variant-to-variant correlation rs143383:rs763110 had a significant adjusted OR = 7.933, q = 0.070).

CONCLUSION

In this large-scale study of common variants' correlation with the presence of DDD in the Northeast United States, we have found a novel and significant variant-to-variant interaction to be associated with the risk of developing DDD, corroborating and necessitating the inclusion of gene-gene interactions in predictive risk model development for DDD.Level of Evidence: 4.

[Back pain and intervertebral disc degeneration in the International Classification of Diseases 11th revision]

In 2018, the World Health Organization introduced a new version of the International Classification of Diseases (ICD-11), which is preliminary and introductory in nature and will come into force on 1 January 2022. One of the most changed sections compared to ICD-10 is the section characterizing the spine pain syndrome and other manifestations of discogenic pathology. The article describes the terms and codes for the degenerative lesion of the intervertebral disk (IVD) in accordance with the requirements of ICD-11, which also agree with the definitions of the 2nd revision of the nomenclature and classification of the pathology of the lumbar IVD from 2014. The basic concepts of IVD degenerative changes are also revealed. The need to create a new revision of the domestic clinical classification of vertebrogenic neurologic pathology adapted to ICD-11 codes is underlined.

[Watchful waiting as a therapeutic principle for diseases of the vitreoretinal interface]

Elective surgery of the vitreoretinal interface is currently the most common reason for vitrectomy in Germany. The evaluation and correct interpretation of spectral domain optical coherence tomography (SD-OCT) images is of great importance but the indications for vitrectomy in macular surgery should be based more on patient symptoms and not only the OCT findings. Watchful waiting is highlighted as an alternative therapeutic option in individual patients. This article addresses a number of aspects and discrepancies between findings and patients' level of suffering based on binocular symptoms. Postoperative retinal thickening and irregular surface of the macula after peeling operations may still allow excellent function and often require no therapeutic measures. The difficulties in differentiating between cystoid macular edema after cataract operations with simultaneous epiretinal gliosis and gliosis as the cause of macular edema are highlighted.

Bone Marrow-Derived Mesenchymal Stem Cells as Autologous Therapy in Dogs with Naturally Occurring Intervertebral Disc Disease: Feasibility, Safety, and Preliminary Results

The intradiscal application of mesenchymal stem cells (MSCs) is considered a promising strategy for intervertebral disc (IVD) regeneration. Although many studies have been published, the feasibility and regenerative effects of intradiscal MSC application have not been evaluated in an animal model suffering from naturally occurring degenerative disc disease. Six German Shepherd Dogs suffering from naturally occurring degenerative IVD disease were included. Autologous MSCs were isolated from bone marrow (iliac crest) and cultured for 3 weeks. After decompressive spinal surgery, three dogs received an intradiscal injection of MSCs, while the other three dogs received an intradiscal injection of saline (control). Clinical status, disc height index, Pfirrmann grading, and disc volumetry were evaluated at 1, 6, and 12 months after treatment. Autologous application of canine MSCs was feasible and successful in all dogs. No evident complication was found. Surgery resulted in an equal improvement in clinical status in the treatment and control dogs. In the MSC group, the Pfirrmann grade increased in all patients over time, whereas in the control group, the Pfirrmann grade remained stable. The volume of the L7-S1 IVD gradually increased during the 12-month study period in all dogs, with no evident difference between the MSC and control group. On the basis of this preliminary study, it can be concluded that intradiscal injection of autologous MSCs in dogs with spontaneous degenerative IVD disease is well tolerated without any adverse effects, does not affect clinical outcome, and does not have any evident regenerative effects.

MRI Phenotyping of COL9A2/Trp2 and COL9A3/Trp3 Alleles in Lumbar Disc Disease: A Case-control Study in South-Western Iranian Population Reveals a Significant Trp3-Disease Association in Males

STUDY DESIGN

A case-control study of the Trp2/3 alleles of COL9A2/3 genes and their correlation with occurrence of Lumbar disc disease (DDD) as phenotyped by magnetic resonance imaging.

OBJECTIVE

To establish a better understanding of relationship between presence of said alleles and occurrence of DDD in South-Western Iranian population.

SUMMARY OF BACKGROUND DATA

A number of genetic predisposing factors have been identified in elevating the risk of developing DDD. Specifically, the Trp2 and Trp3 alleles of COL9A2 and COL9A3 genes have been suggested as DDD risk variants.

METHODS

A total of 108 patients (mean age = 41±11.8 yrs, range = 20-66 yrs) with 57 controls (mean age = 35±10.0 yrs, range = 20-58 yrs) participated in the study. The frequency of G/A polymorphism in COL9A2 gene on location 326 on chromosome 1 and G/A/C/ or T polymorphism in 103 location of COL9A3 gene on chromosome 20 was assessed using a PCR short-primer technique. Outcome measure was defined as presence of DDD on MRI. Odds ratios (OR) and 95% confidence intervals (CI) were used to assess the likelihood of DDD given occurrence of Trp2(3).

RESULTS

Each allele was present in both patients and controls. The Trp2 allele was positive in 28.5% of individuals (31.5% of patients; 22.8% of controls), OR 1.55 (0.71-3.56). The Trp3 allele, the frequency was 23.6% in all patients (26.9% patients; 17.5% controls), OR 1.72 (0.73-4.33). We observed a 5.8-fold increase in the odds of DDD in males when the Trp3 allele was present, OR 5.83 (1.09-9.98), P = 0.0273.

CONCLUSION

Both Trp2 and Trp3 alleles occurred more frequently compared with other studied ethnicities. The sampled Iranian population exhibited a similar Trp2 frequency to a Southern Chinese population, and Trp3 occurrence to Finnish and Greek population. We found that male patient were much more likely to develop DDD when Trp 3 was present.

LEVEL OF EVIDENCE

N/A.

A review of the value of MRI signs in low back pain

Low back pain is a common symptom that can lead to disability and major socio-professional repercussions. Despite advances in imaging, the etiology of the pain often remains unknown. Morphological changes related to normal ageing of the disc appear on MR imaging without any symptoms. The potential impact of changes seen on imaging, especially MRI, also warrants discussion. The purpose of this work is to review the state-of-the-art of this subject, underlining relevant key features for routine radiological practice. We will first discuss anterior and posterior segments of the spine with a focus on anatomical, physiopathological and semiological findings. Secondly we will discuss the diagnostic value of each sign.

Segmental lumbar rotation in patients with discogenic low back pain during functional weight-bearing activities

BACKGROUND

Little information is available on vertebral motion in patients with discogenic low back pain under physiological conditions. We previously validated a combined dual fluoroscopic and magnetic resonance imaging system to investigate in vivo lumbar kinematics. The purpose of the present study was to characterize mechanical dysfunction among patients with confirmed discogenic low back pain, relative to asymptomatic controls without degenerative disc disease, by quantifying abnormal vertebral motion.

METHODS

Ten subjects were recruited for the present study. All patients had discogenic low back pain confirmed clinically and radiographically at L4-L5 and L5-S1. Motions were reproduced with use of the combined imaging technique during flexion-extension, left-to-right bending, and left-to-right twisting movements. From local coordinate systems at the end plates, relative motions of the cephalad vertebrae with respect to caudad vertebrae were calculated at each of the segments from L2 to S1. Range of motion of the primary rotations and coupled translations and rotations were determined.

RESULTS

During all three movements, the greatest range of motion was observed at L3-L4. L3-L4 had significantly greater motion than L2-L3 with left-right bending and left-right twisting movements (p < 0.05). The least motion occurred at L5-S1 for all movements; the motion at this level was significantly smaller than that at L3-L4 (p < 0.05). Range of motion during left-right bending and left-right twisting at L3-L4 was significantly larger in the degenerative disc disease group than in the normal group. The range of motion at L4-L5 was significantly larger in the degenerative group than in the normal group during flexion; however, the ranges of motion in both groups were similar during left-to-right bending and left-to-right twisting.

CONCLUSIONS

The greatest range of motion in patients with discogenic back pain was observed at L3-L4; this motion was greater than that in normal subjects, suggesting that superior adjacent levels developed segmental hypermobility prior to undergoing fusion. L5-S1 had the least motion, suggesting that segmental hypomobility ensues at this level in patients with discogenic low back pain.