Familial predisposition for lumbar degenerative disc disease. A case-control study

Surgically Treated Degenerative Lumbar Spine Diseases in Twins

BACKGROUND

There is growing evidence to suggest a potential genetic component underlying the development and progression of lumbar spine diseases. However, the heritability and the concordance rates for the phenotypes requiring surgery for the common spine diseases lumbar spinal stenosis (LSS) and lumbar disc herniation (LDH) are unknown. The aim of this study was to determine the heritability and the concordance rates for LSS and LDH requiring surgery by studying monozygotic (MZ) and dizygotic (DZ) twin pairs.

METHODS

Patients between 18 and 85 years of age who underwent surgery for LSS or LDH between 1996 and 2022 were identified in the national Swedish spine registry (LSS: 45,110 patients; LDH: 39,272 patients), and matched with the Swedish Twin Registry to identify MZ and DZ twins. Pairwise and probandwise concordance rates, heritability estimates, and MZ/DZ concordance ratios were calculated.

RESULTS

We identified 414 twin pairs (92 MZ and 322 DZ pairs) of whom 1 or both twins underwent surgery for LSS. The corresponding number for LDH was 387 twin pairs (118 MZ and 269 DZ pairs). The probandwise concordance rate for LSS requiring surgery was 0.25 (26 of 105) (95% confidence interval [CI], 0.14 to 0.34) for MZ twins and 0.04 (12 of 328) (95% CI, 0.01 to 0.07) for DZ twins. The corresponding values for LDH requiring surgery were 0.03 (4 of 120) (95% CI, 0 to 0.08) and 0.01 (4 of 271) (95% CI, 0 to 0.04), respectively. The probandwise MZ/DZ concordance ratio was 6.8 (95% CI, 2.9 to 21.5) for LSS and 2.3 (95% CI, 0 to 8.9) for LDH. The heritability was significantly higher in LSS compared with LDH (0.64 [95% CI, 0.50 to 0.74] versus 0.19 [95% CI, 0.08 to 0.35]).

CONCLUSIONS

Our findings suggest that genetic factors may play an important role in the risk of developing LSS requiring surgery, whereas heredity seems to be of less importance in LDH requiring surgery.

LEVEL OF EVIDENCE

Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Surgically treated degenerative disk disease in twins

PURPOSE

Previous studies have suggested that genetic factors are important in the development of degenerative disk disease (DDD). However, the concordance rates for the phenotypes requiring surgery are unknown. The purpose of this study was to determine the concordance rates for DDD requiring surgery by studying monozygotic (MZ) and dizygotic (DZ) twin pairs.

METHODS

Patients, aged between 18 and 85 years, operated for DDD between 1996 and 2022 were identified in the national Swedish spine register (Swespine) and matched with the Swedish twin registry (STR) to identify MZ and DZ twins. Pairwise and probandwise concordance rates were calculated.

RESULTS

We identified 11,207 patients, 53% women, operated for DDD. By matching the Swespine patients with the STR, we identified 121 twin pairs (37 MZ and 84 DZ) where one or both twins were surgically treated for DDD. The total twin incidence for operated DDD was 1.1%. For DDD requiring surgery, we found no concordant MZ pair and no concordant DZ pair where both twins were operated for DDD. When we evaluated pairs where at least one twin was operated for DDD, we found two concordant MZ pairs (the co-twins were operated for spinal stenosis) and two  concordant DZ pairs (one co-twin operated for spinal stenosis and one (co-twin operated for disk herniation).

CONCLUSIONS

Our findings suggest that genetic factors are probably not a major etiologic component in most cases of DDD requiring surgery. The findings of this study can be used for counseling patients about the risk for requiring DDD surgery.

Genetics of Intervertebral Disc Degeneration

PURPOSE OF REVIEW

Intervertebral disc degeneration is a contributor to chronic back pain. While a part of the natural aging process, early or rapid intervertebral disc degeneration is highly heritable. In this review, we summarize recent progress towards unraveling the genetics associated with this degenerative process.

RECENT FINDINGS

Use of large cohorts of patient data to conduct genome-wide association studies (GWAS) for intervertebral disc disease, and to lesser extent for aspects of this process, such as disc height, has resulted in a large increase in our understanding of the genetic etiology. Genetic correlation suggests that intervertebral disc disease is pleiotropic with risk factors for other diseases such as osteoporosis. The use of Mendelian Randomization is slowly establishing what are the causal relationships between intervertebral disc disease and factors previously correlated with this disease. The results from these human genetic studies highlight the complex nature of this disease and have the potential to lead to improved clinical management of intervertebral disc disease. Much additional work should now be focused on characterizing the causative relationship various co-morbid conditions have with intervertebral disc degeneration and on finding interventions to slow or halt this disease.

Association Between Family History of Surgically Treated Low Back Pain and Adolescent Low Back Pain

STUDY DESIGN

Cross-sectional.

OBJECTIVE

To study the associations between a family history of surgically treated low back pain (LBP) and adolescent LBP.

SUMMARY OF BACKGROUND DATA

A family history of LBP is related to adolescent LBP, but whether a family history of back surgery is relevant to adolescent LBP is not known.

METHODS

A subpopulation of the Northern Finland Birth Cohort 1986 was contacted when they were aged between 18 and 19years. The postal questionnaire asked the participants to report their LBP and a relative's (mother, father, sibling) LBP and back surgery, and to provide data on potential covariates. The association between a family history of LBP ("no family history of LBP," "family history of LBP but no surgery," and "family history of LBP and surgery") and adolescent LBP (no LBP, occasional LBP, and frequent LBP) were evaluated using logistic regression analysis with odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for sex, smoking, and psychological distress.

RESULTS

Of the 1374 adolescents in the study, 33% reported occasional LBP and 9% frequent LBP. Both the "family history of LBP but no surgery" and "family history of LBP and surgery" categories were associated with frequent LBP (adjusted OR [aOR] 2.09, 95% CI 1.38-3.16; aOR 2.23, 95% CI 1.02-4.90, respectively). Occasional LBP was associated with the "family history of LBP and surgery" category. A subgroup analysis of adolescents with a family history of LBP found no statistically significant associations between family history of back surgery and adolescent LBP.

CONCLUSION

Our findings suggest that adolescents who report a family history of LBP have higher odds of frequent LBP irrespectively of a family history of back surgery.Level of evidence: 4.

Correlation between motor behavior and age-related intervertebral disc degeneration in cynomolgus monkeys

Background

The motor behavior in patients with lumbar intervertebral disc degeneration (IDD) and animal models should be changed due to pain. However, there does not seem to be a strong correlation between IDD and motor behavior. Therefore, it is necessary to understand the correlation between motor behavior and age‐related IDD.

Methods

Twenty‐one healthy male cynomolgus monkeys (Macaca fascicularis) distributed across the age range were included in this study. The experimental animals were divided into two groups: caged group (n = 14) and free‐range group (n = 7). The data of IDD and motor behavior were obtained through magnetic resonance imaging (MRI) and PrimateScan Automatic Behavior Analysis System. More than 20 basic motor behaviors could be recorded and quantified, and then reclassified into 9 combined categories. We defined the sum of the duration of activity‐related combined categories as the total duration of activity in 3 hours. The activity zone of the cynomolgus monkeys in the cage could be divided into top and bottom zones. Analyze the correlation between motor behavior and IDD.

Results

Age was correlated with both Pfirrmann grades (r = .700; P < .001) and T2 values (r = −.369; P < .001). The T2 value in the caged group was 45.97 ± 8.35 ms, which was significantly lower than the 55.90 ± 8.73 ms in the free‐range group (P < .001). The mean T2 values were positively correlated with hanging duration (r = .548, P < .05), the total duration of activity (r = .496, P < .05), and top zone duration (r = .541, P < .05).

Conclusions

There is an interactional relationship between IDD and motor behavior. Motor behavior could be used as one of the diagnostic indicators of IDD. It could also be used to infer the presence or extent of IDD in animal models. Avoiding a sedentary lifestyle and engaging in exercise in daily life could alleviate IDD.

Expression of HSPA8 in Nucleus Pulposus of Lumbar Intervertebral Disc and Its Effect on Degree of Degeneration

INTRODUCTION

This study aimed to investigate the expression of a 70-kDa heat shock protein [heat shock 70-kDa protein 8 (HSPA8)/heat shock protein 70 (Hsc70)] in human degenerative lumbar intervertebral discs and its relationship with the degree of degeneration of human intervertebral discs.

METHODS

A total of 72 cases of lumbar intervertebral disc nucleus pulposus tissues were collected. Among these, 18 cases of nucleus pulposus tissue were assigned to the control group, while 54 cases of nucleus pulposus tissues were assigned to the experimental group. According to the preoperative MRI, cases in the experimental group were further divided into three groups: protrusion group (n = 18), extrusion group (n = 18), and sequestration group (n = 18). Western blot was performed to determine the relative expression of HSPA8 in the nucleus pulposus in each group. Hematoxylin and eosin staining was performed to determine the number of nucleus pulposus cells, morphological differences, and cell densities of the degenerated intervertebral discs and normal intervertebral discs. Immunohistochemistry was performed to determine the expression of HSPA8 in nucleus pulposus tissues in each group.

RESULTS

Hematoxylin and eosin staining results: There were significant differences in cell morphology and number between the control group and the experimental group. Furthermore, there were significant differences in cell density (F = 936.80, P < 0.01). Immunohistochemistry results: HSPA8 was expressed in lumbar intervertebral disc nucleus pulposus tissues, and its expression of gradually decreased with the severity of the disease, and the differences were significant (F = 2110.43, P < 0.01). Western blot results: The expression of HSPA8 in human degenerative nucleus pulposus tissues gradually decreased, and the differences were significant (F = 1841.72, P < 0.01).

CONCLUSION

HSPA8 is stably expressed in human intervertebral disc nucleus pulposus tissues, and its expression is associated with the degree of intervertebral disc degeneration.

Stem cell therapy in discogenic back pain

Chronic low back pain has both substantial social and economic impacts on patients and healthcare budgets. Adding to the magnitude of the problem is the difficulty in identifying the exact causes of disc degeneration with modern day diagnostic and imaging techniques. With that said, current non-operative and surgical treatment modalities for discogenic low back pain fails to meet the expectations in many patients and hence the challenge. The objective for newly emerging stem cell regenerative therapy is to treat degenerative disc disease (DDD) by restoring the disc's cellularity and modulating the inflammatory response. Appropriate patient selection is crucial for the success of stem cell therapy. Regenerative modalities for discogenic pain currently focus on the use of either primary cells harvested from the intervertebral discs or stem cells from other sources whether autogenic or allogenic. The microenvironment in which stem cells are being cultured has been recognized to play a crucial role in directing or maintaining the production of the desired phenotypes and may enhance their regenerative potential. This has led to a more specific focus on innovating more effective culturing techniques, delivery vehicles and scaffolds for stem cell application. Although stem cell therapy might offer an attractive alternative treatment option, more clinical studies are still needed to establish on the safety and feasibility of such therapy. In this literature review, we aim to present the most recent in vivo and in vitro studies related to the use of stem cell therapy in the treatment of discogenic low back pain.

Genetic variants in COL11A2 of lumbar disk degeneration among Chinese Han population

BACKGROUND

Lumbar disk disease (LDD) is a common musculoskeletal disorder. Several predisposing genetic and environmental risk factors have been established for symptomatic LDD.

METHODS

We conducted a case-control association study to investigate the role of the COL11A2 gene in LDD. Genotyping of 384 Chinese Han LDD patients and 384 Chinese Han controls was made for six single-nucleotide polymorphisms (SNPs) from COL11A2 by Agena Massarray. We evaluated these SNPs association with LDD using the chi-square test and genetic model analysis.

RESULTS

The strongest associations with LDD were observed for polymorphisms in rs2071025. Carriers of "A" allele had an increased risk of LDD (OR = 1.47, 95% CI = 1.20-1.80, p = 0.0002) as compared with the "G" allele in allele model. We found that rs2071025 were associated with LDD in female and male from the stratification analyses (p < 0.05). Genetic models showed that rs986522(C) significantly increased the risk of LDD in female; however, in males, we did not find significant associations between the rs986522 and LDD risk.

CONCLUSION

This study showed a genetic association with COL11A2 polymorphism in individuals with LDD. These data may provide novel insights into the pathogenesis of LDD, although further studies with larger numbers of participants worldwide are needed for validation of our conclusions.

FokI as a genetic factor of intervertebral disc degeneration: A PRISMA-compliant systematic review of overlapping meta-analyses

The association of FokI (rs2228570), a polymorphism of the vitamin D receptor gene, with intervertebral disc degeneration (IDD) has been investigated in a multitude of studies. However, conflicting results of these studies led to emergence of several meta-analyses over the past few years. Despite the increased statistical power, these meta-analyses have failed to provide uniform and conclusive data on the relationship of FokI with IDD. The aim of this study was to present a comprehensive review based on the most up-to-date meta-analyses on the association of FokI with IDD. A comprehensive search of all major databases was conducted to identify meta-analyses investigating relation between FokI and IDD. No date or language restrictions were applied. The Jadad decision algorithm was utilized to evaluate included meta-analyses and identify the one providing the best evidence. A total of 7 meta-analyses (n = 2580 original patients), that included six to ten case control studies, analyzed the association of FokI polymorphism with IDD. The meta-analysis of the highest quality supported the notion that overall there is no statistically significant association between FokI polymorphism and IDD. However, the authors showed that Caucasians have a reduced risk of IDD and Hispanics have an increased risk of IDD in the dominant and dominant/homozygous/heterozygous models of FokI polymorphism. While currently there is no evidence of an association between FokI polymorphism and IDD in the general population, ethnic predisposition has been shown.

Association of CILP, COL9A2 and MMP3 Gene Polymorphisms with Lumbar Disc Degeneration in an Indian Population

Lumbar disc degeneration (LDD) is a multifactorial disorder caused by genetic and environmental factors. Polymorphisms in several structural and inflammatory genes like collagens, aggrecan, matrix metalloproteinases are associated with the risk of disc degeneration. In this study, we analyzed the role of a few important single nucleotide polymorphisms in cartilage intermediate layer protein (CILP), collagen 9A2 (COL9A2) and matrix metalloproteinase 3 (MMP3) genes in LDD from an Indian population. Two hundred patients with LDD and 200 healthy controls were recruited for the study. Genotyping was performed by allelic discrimination assay. The rs2073711 polymorphism (CILP gene - GG genotype) was associated with reduced risk of LDD in the Indian population (OR = 0.43, p = 0.016). The rs591058 polymorphism (MMP3 gene - TT genotype) is found to be associated with lower risk among women (OR = 0.34, p = 0.041). No significant association was found between COL9A2 polymorphism rs7533552 and the risk of LDD. We conclude that the CILP gene polymorphism (rs2073711) is associated with a lower risk of LDD, the MMP3 (rs591058) gene polymorphism is associated with LDD among women, and the TT genotype confers a lower risk of LDD.

Genetic background of degenerative disc disease in the lumbar spine

This is a review paper on the topic of genetic background of degenerative disc diseases in the lumbar spine. Lumbar disc diseases (LDDs), such as lumbar disc degeneration and lumbar disc herniation, are the main cause of low back pain. There are a lot of studies that tried to identify the causes of LDDs. The causes have been categorized into environmental factors and genetic factors. Recent studies revealed that LDDs are mainly caused by genetic factors. Numerous studies have been carried out using the genetic approach for LDDs. The history of these studies is divided into three periods: (1) era of epidemiological research using familial background and twins, (2) era of genomic research using DNA polymorphisms to identify susceptible genes for LDDs, and (3) era of functional research to determine how the genes cause LDDs. This review article was undertaken to present the history of genetic approach to LDDs and to discuss the current issues and future perspectives.

Circular RNA GRB10 as a competitive endogenous RNA regulating nucleus pulposus cells death in degenerative intervertebral disk

Intervertebral disc degeneration (IDD) is an important factor leading to low back pain, but the underlying mechanisms remain poorly understood. Compared with normal nucleus pulposus (NP) tissues, the expression of circ-GRB10 was downregulated in IDD. Furthermore, overexpression of circ-GRB10 inhibited NP cell apoptosis. circ-GRB10 could sequester miR-328-5p, which could potentially lead to the upregulation of target genes related to cell proliferation via the ErbB pathway. In conclusion, the present study revealed that circ-GRB10/miR-328-5p/ERBB2 signaling pathway is involved in IDD development, suggesting that circ-GRB10 might be a novel therapeutic target for IDD.

Novel Genetic Variants Associated with Lumbar Spondylosis in Koreans : A Genome-Wide Association Study

Objective

The aim of this study was to identify the susceptibility genes responsible for lumbar spondylosis (LS) in Korean patients.

Methods

Data from 1427 subjects were made available for radiographic grading and genome wide association studies (GWAS) analysis. Lateral lumbar spine radiographs were obtained and the various degrees of degenerative change were semi-quantitatively scored. A pilot GWAS was performed using the AffymetrixGenome-Wide Human single-nucleotide polymorphisms (SNPs), 500K array. A total of 352228 SNPs were analyzed and the association between the SNPs and case-control status was analyzed by stepwise logistic regression analyses.

Results

The top 100 SNPs with a cutoff p-value of less than 3.7×10^-4 were selected for joint space narrowing, while a cutoff p-value of 6.0×10^-4 was applied to osteophytes and the Kellgren-Lawrence (K-L) osteoarthritis grade. The SNPs with the strongest effect on disc space narrowing, osteophytes, and K-L grade were serine incorporator 1 (rs155467, odds ratio [OR]=17.58, p=1.6×10^-4), stromal interaction molecule 2 (STIM1, rs210781, OR=5.53, p=5×10^-4), and transient receptor potential cation channel, subfamily C (rs11224760, OR=3.99, p=4.8×10^-4), respectively. Leucine-rich repeat-containing G protein-coupled receptor 4 was significantly associated with both disc space narrowing and osteophytes (rs1979400, OR=2.01, p=1.1×10^-4 for disc space narrowing, OR=1.79, p=3×10^-4 for osteophytes), while zinc finger and BTB domain containing 7C was significantly and negatively associated with both osteophytes and a K-L grade >2 (rs12457004,OR=0.25, p=5.8×10^-4 and OR=0.27, p=5.3×10^-4, respectively).

Conclusion

We identified SNPs that potentially contribute to the pathogenesis of LS. This is the first report of a GWAS in an Asian population.

Asthma and early herniated intervertebral disc disease

BACKGROUND

The etiology of herniated intervertebral disc (HIVD) disease in children and adolescents is multifactorial and not merely related to disc degeneration. Therefore, in the present study, we investigated the relationship between young asthma patients and the risk of early HIVD disease in a population under 30 years of age.

METHODS

Data from the National Health Insurance Research Database (NHIRD) of Taiwan were used to conduct a retrospective longitudinal cohort study. The study cohort comprised 23,470 patients with asthma (asthma group) and 23,470 patients without asthma (non-asthma group), who were selected through frequency matching on the basis of sex, age, and the index year. The study patients were followed until HIVD disease occurrence, withdrawal from the National Health Insurance program, or 31 December 2013. Cox proportional hazards regression analysis was conducted to assess the risk of HIVD disease in the asthma group after adjustment for sex, age, and comorbidities.

RESULTS

After adjustment for sex, age, and comorbidities, the asthma group had a 1.69-fold (95% confidence interval [CI] = 1.29-2.23) higher risk of HIVD disease than did the non-asthma group. In addition, the asthma group had a higher risk of cervical and lumbar HIVD diseases than did the non-asthma group (adjusted hazard ratio [HR] = 2.38; 95% CI = 1.25-4.57 and adjusted HR = 1.56; 95% CI = 1.15-2.12, respectively).

CONCLUSIONS

Young patients with asthma are at a significantly higher risk of early cervical or lumbar HIVD disease.

Association of COL11A1 4603C/T polymorphism with cervical disc degeneration in collegiate wrestlers

BACKGROUND

The authors previously identified that COL11A1 gene polymorphism is not a susceptibility factor for lumbar disc degeneration (LDD) in athletes. However, the relationship between COL11A1 gene polymorphism and cervical disc degeneration (CDD) remains unclear. We hypothesized that significant associations between COL11A1 4603C/T gene polymorphism and CDD, but not LDD, in collegiate wrestlers exist. This study aims to examine the relationship between CDD, LDD, and COL11A1 4603C/T gene polymorphism in collegiate wrestlers.

METHODS

The subjects enrolled in this study were 92 (Study-1) and 123 (Study-2) Japanese collegiate male wrestlers. Study-1 and Study-2 were conducted in 2010-2012 and 2012-2015, respectively.

RESULTS

CDD and LDD prevalence among the wrestlers was 51.1% (47/92) and 43.9% (54/123), respectively. We found that COL11A1 4603C/T was significantly associated with CDD, but not with LDD. Using logistic regression analysis with concomitant confounding factors, we further confirmed that COL11A1 4603C/T was a significant risk factor for CDD (co-dominant genetic model [CC vs. CT+TT]: adjusted odds ratio [OR] 2.28; 95% CI: 1.13-4.59; dominant genetic model [CC+CT vs. TT]: adjusted OR 11.71; 95% CI: 1.36-101.06).

CONCLUSIONS

Results suggest that COL11A1 4603C/T gene polymorphism is associated with an increased risk of CDD, but not LDD, in Japanese collegiate wrestlers.

Bedside to bench and back to bedside: Translational implications of targeted intervertebral disc therapeutics

Spinal pain and associated disability is a leading cause of morbidity worldwide that has a strong association with degenerative disc disease (DDD). DDD can begin in early–late adolescence and has a variable course. Biologically based therapies to treat DDD face significant challenges posed by the unique milieu of the environment within the intervertebral discs. Many potential promising therapies are still in the early stages of development with a hostile microenvironment within the disc presenting unique challenges.

The translational potential of this article: Patient selection, reasonable therapeutic goals, approach, and timing will need to be discerned in order to successfully translate potential therapeutics.

The Role of Ergonomics in Reducing Low Back Pain and Disability in the Workplace

Low back pain is a common problem, an expensive problem, and a recurring problem. In this paper, the problem is defined, the available evidence is reviewed, and three types of interventions are discussed. The interventions are job design, changing personal behavior and beliefs, and secondary intervention to reduce the disability. Ergonomics plays an important role in each of the interventions. Although low back pain cannot be completely prevented, the evidence indicates that it can be reduced and managed with considerable success.

Association Between Lumbar Disc Degeneration and Propionibacterium acnes Infection: Clinical Research and Preliminary Exploration of Animal Experiment

STUDY DESIGN

Clinical research and animal experiment.

OBJECTIVE

To investigate whether lumbar disc degeneration is associated with Propionibacterium acnes (P acnes) infection.

SUMMARY OF BACKGROUND DATA

The hypothesis that herniated discs may be infected with P acnes by way of bacteremia is remarkable. This may bring a tremendous change in treatment of lumbar disc herniation (LDH). However, this hypothesis is still controversial. Since P acnes isolated may be related to contamination.

METHODS

Nucleus pulposus from 22 patients (30 discs) with lumbar disc herniation was collected during discectomy, following aerobic and anaerobic cultures for 10 days.Twenty-four rabbits were divided into four groups. After L3-L6 being exposed, an incision was made into the three discs in groups A and B. While in groups C and D, two random segments were operated. Six weeks later, 0.05 mL of 5 × 10 CFU/mL P acnes was inoculated into operated discs in group A and sterile physiological saline in group B. In group C, 0.2 mL of 5 × 10 CFU/mL P acnes was injected through ear vein. Sterile saline was used in group D. Six weeks later, MRI was performed. Then, nucleus pulposus and paraspinal muscles were harvested for aerobic and anaerobic cultures.

RESULTS

Clinical research: Anaerobic cultures were positive in three cases: two coagulase-negative staphylococci, one particles chain bacterium. No P acnes was found. Staphylococcus epidermidis was isolated in one aerobic culture.Animal experiment: P acnes was found in 11 out of 18 (61%) discs in group A. There was no P acnes found in the other three groups.

CONCLUSION

Degenerated discs were suitable for P acnes growth. This research did not find the evidence of the symptomatic degenerated lumbar discs infected with P acnes or that P acnes could infect the degenerated lumbar discs by way of bacteremia.

LEVEL OF EVIDENCE

N/A.

A history of lumbar disc herniation from Hippocrates to the 1990s

In ancient times, a supernatural understanding of the syndrome of lumbar radiculopathy often involved demonic forces vexing the individual with often crippling pain. The ancient Greeks and Egyptians began to take a more naturalistic view and, critically, suspected a relationship between lumbar spinal pathology and leg symptoms. Relatively little then changed for those with sciatica until the classic works by Cotugno and Kocher arrived in the late 18th century. Early lumbar canal explorations were performed in the late 1800s and early 1900s by MacEwen, Horsley, Krause, Taylor, Dandy, and Cushing, among others. In these cases, when compressive pathologies were found and removed, the lesions typically were (mis-)identified as enchondromas or osteochondritis dissecans. To better understand the history, learn more about the first treatments of lumbar disc herniation, and evaluate the impact of the early influences on modern spine practice, searches of PubMed and Embase were performed using the search terms discectomy, medical history, lumbar spine surgery, herniated disc, herniated nucleus pulposus, sciatica, and lumbar radiculopathy. Additional sources were identified from the reference lists of the reviewed papers. Many older and ancient sources including De Ischiade Nervosa are available in English translations and were used. When full texts were not available, English abstracts were used. The first true, intentional discectomy surgery was performed by Mixter and Barr in 1932. Early on, a transdural approach was favored. In 1938, Love described the intralaminar, extradural approach. His technique, although modified with improved lighting, magnification, and retractors, remains a staple approach to disc herniations today. Other modalities such as chymopapain have been investigated. Some remain a part of the therapeutic armamentarium, whereas others have disappeared. By the 1970s, CT scanning after myelography markedly improved the clinical evaluation of patients with lumbar disc herniation. In this era, use of discectomy surgery increased rapidly. Even patients with very early symptoms were offered surgery. Later work, especially by Weber and Hakelius, showed that many patients with lumbar disc herniation would improve without surgical intervention. In the ensuing decades, the debate over operative indications and timing continued, reaching another pivotal moment with the 2006 publication of the initial results of Spine Patient Outcomes Research Trial.

Delivery systems for the treatment of degenerated intervertebral discs

The intervertebral disc (IVD) is the most avascular and acellular tissue in the body and therefore prone to degeneration. During IVD degeneration, the balance between anabolic and catabolic processes in the disc is deregulated, amongst others leading to alteration of extracellular matrix production, abnormal enzyme activities and production of pro-inflammatory substances like cytokines. The established treatment strategy for IVD degeneration consists of physiotherapy, pain medication by drug therapy and if necessary surgery. This approach, however, has shown limited success. Alternative strategies to increase and prolong the effects of bioactive agents and to reverse the process of IVD degeneration include the use of delivery systems for drugs, proteins, cells and genes. In view of the specific anatomy and physiology of the IVD and depending on the strategy of the therapy, different delivery systems have been developed which are reviewed in this article.

Analysis of FokI polymorphism of vitamin D receptor gene in intervertebral disc degeneration

AIM

We have hypothesized a possible relationship between disc degeneration (DD) and VDR FokI/T2C polymorphism.

METHODS

A case-control study was performed comprising 121 Brazilian patients with confirmed DD by nuclear magnetic resonance and a control group consisting of 131 healthy patients without a history of disc cysts of the lumbar spine. Detection of VDR FokI/T2C polymorphism was performed using restriction fragment length polymorphism-polymerase chain reaction. The chi-square test was used to compare allele and genotype frequencies between groups, and a p-value of <0.05 was considered statistically significant.

RESULTS

The results disclosed statistical difference between allele distribution among cases and controls (p=0.025, odds ratio=1.58, confidence interval=1.07-2.32) considering VDR FokI/T2C polymorphism.

CONCLUSION

The results showed a positive association between VDR FokI/T2C polymorphism and DD in Brazilian patients tested.

FokI polymorphism in the vitamin D receptor gene (VDR) and its association with lumbar spine pathologies in the Italian population: a case-control study

Alterations in vitamin D homeostasis, mainly involving its nuclear receptor (VDR), could have a role in the pathophysiology of the spine. The association between VDR polymorphisms and spine disorders has been analyzed in different ethnic groups, focusing on the functional FokI polymorphism. However, so far, inconsistent findings were reported. The aims of this study were to evaluate, in the Italian white population, the VDR FokI polymorphism frequencies distribution in subjects with clearly defined lumbar spinal pathologies compared to asymptomatic controls and to analyze the interplay of genetic and conventional risk factors. Using a case-control design, 267 patients with spinal disorders and 220 asymptomatic controls were enrolled, evaluating their exposition to putative risk factors. Patients’ clinical assessment was performed by Magnetic Resonance Imaging. FokI polymorphism (rs2228570) was detected by PCR-RFLP. Genotypes were designated by a lowercase letter (f allele, T nucleotide) for the presence of the restriction site and by a capital letter (F allele, C nucleotide) for its absence. Family history, higher age and BMI, exposure to vibration, physical job demand, smoking habit and lower practice of leisure physical activity were associated with spinal disorders. The FF genotype and F allele represented approximately 2-fold risk factors to develop discopathies and/or osteochondrosis concomitant with disc herniation, while f allele was protective. In conclusion, the link we observed between VDR FokI variants and specific lumbar spine pathologies suggests that spinal tissue degeneration is influenced by the genetic background. Future studies should evaluate the signaling pathways involving alterations in VDR and influencing the development and/or progression of spine disorders.

Distribution pattern of surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs in males

Background:

The pattern of distribution of surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs has been published, though scantily, especially in males. We decided to look at our own series, compare and contrast ours with some of those published.

Materials and Methods:

We treated 88 locations of this lesion in 68 males. The clinical features were those of lower back pains, with or without radiation into the lower extremities, sensory loss and paresis of the limbs. There was a case of loss of urinary bladder and ano-rectal control. All lesions were confirmed through cauda-equinograms and treated under general anaesthesia in knee-chest position (MECCA position). The patients were followed up for 3-6 months post-operatively.

Results:

There were 88 locations in 68 males of 21-70 years of age, with 29 prolapses occurring during the age range 31-40 years, while 54 locations were on the left and 48 at L4/5. The procedures were well tolerated by all patients and there were no post-operative complications.

Conclusion:

This lesion in our series occurred mostly on the left, at the L4/5 level and peaked at 31-40 years age range. The predictability of occurrence of this disease, using side, level and age is still not feasible in males from our series.

Relationship between vitamin D receptor gene (VDR) polymorphisms, vitamin D status, osteoarthritis and intervertebral disc degeneration

The vitamin D endocrine system is involved in bony and cartilaginous metabolisms and alterations in the homeostasis of this system could be associated to pathological conditions of cartilaginous tissue. In this context, the presence of polymorphisms in the vitamin D receptor gene (VDR), in association with the susceptibility to common osteochondral diseases, was largely investigated. The aim of this review was to summarize data present in literature, analyzing the association of the VDR polymorphisms, vitamin D status and knee cartilage and intervertebral disc pathologies, trying to suggest links between the different specific pathologies analyzed. Concerning the association between VDR polymorphisms and cartilaginous tissue diseases, we found controversial reports. However, the great majority of papers reported an association with lumbar disc degeneration, whereas about half of the studies found an association with osteoarthritis. A further association between VDR polymorphisms (in linkage disequilibrium) and the presence of specific characteristics of these diseases, in particular the formation of osteophytes, was evidenced. Finally, the influence of vitamin D status on these pathologies was evaluated, trying to evidence the relation between the presence of particular genetic variants in the VDR and vitamin D levels or to show whether a particular vitamin D status could predispose to the development or progression of such diseases, however, no significant associations were found. In the future, given the role of vitamin D system in the cartilaginous tissue metabolism, it could be interesting to perform functional and tissue specific studies to analyze the interplay between the different VDR variants and its ligand.

Lumbar disc degeneration is linked to a carbohydrate sulfotransferase 3 variant

Lumbar disc degeneration (LDD) is associated with both genetic and environmental factors and affects many people worldwide. A hallmark of LDD is loss of proteoglycan and water content in the nucleus pulposus of intervertebral discs. While some genetic determinants have been reported, the etiology of LDD is largely unknown. Here we report the findings from linkage and association studies on a total of 32,642 subjects consisting of 4,043 LDD cases and 28,599 control subjects. We identified carbohydrate sulfotransferase 3 (CHST3), an enzyme that catalyzes proteoglycan sulfation, as a susceptibility gene for LDD. The strongest genome-wide linkage peak encompassed CHST3 from a Southern Chinese family–based data set, while a genome-wide association was observed at rs4148941 in the gene in a meta-analysis using multiethnic population cohorts. rs4148941 lies within a potential microRNA-513a-5p (miR-513a-5p) binding site. Interaction between miR-513a-5p and mRNA transcribed from the susceptibility allele (A allele) of rs4148941 was enhanced in vitro compared with transcripts from other alleles. Additionally, expression of CHST3 mRNA was significantly reduced in the intervertebral disc cells of human subjects carrying the A allele of rs4148941. Together, our data provide new insights into the etiology of LDD, implicating an interplay between genetic risk factors and miRNA.

Polymorphism in the hypoxia-inducible factor 1alpha gene may confer susceptibility to LDD in Chinese cohort

Objective

This study aimed to investigate whether or not hypoxia-inducible factor-1α (HIF-1α) gene variants are associated with the susceptibility and clinical characteristics of lumbar disc degeneration (LDD).

Methods

We examined 320 patients with LDD and 447 gender- and age-matched control subjects. We also determined the HIF-1α gene variants, including C1772T (P582S) and G1790A (A588T) polymorphisms.

Results

Significant differences were observed in allelic and genotypic distributions of 1790 A > G polymorphisms between LDD cases and control subjects. Logistic regression revealed that 1790 AA genotypes indicated a protective effect against the development of LDD. The HIF-1α 1790 A > G polymorphisms also affected the severity of LDD as evaluated based on the modified Japanese Orthopedic Association (mJOA) scores. The 1790 AA genotype carriers exhibited significantly lower mJOA scores than AG and GG carriers. C1772T did not show any association with the risk and severity of LDD.

Conclusion

Our study suggested that HIF-1α 1790 A > G polymorphisms may be used as a molecular marker to determine the susceptibility and severity of LDD.

Anterior Limbus Vertebra and Intervertebral Disk Degeneration in Japanese Collegiate Gymnasts

Background:

Magnetic resonance imaging (MRI) studies have shown that gymnasts have a high prevalence of radiological abnormalities, such as intervertebral disk degeneration (IDD) and anterior limbus vertebra (ALV). These 2 abnormalities may coexist at the same spinal level. However, the relationship between IDD and ALV remains unclear.

Hypothesis:

A significant relationship exists between IDD and ALV in Japanese collegiate gymnasts.

Study Design:

Case-control study.

Methods:

A total of 104 Japanese collegiate gymnasts (70 men and 34 women; age, 19.7 ± 1.0 years) with 11.8 ± 3.6 years of sporting experience participated. T1- and T2-weighted MRIs were used to evaluate ALV and IDD.

Results:

The prevalence among the gymnasts of IDD and ALV was 40.4% (42/104) and 20.2% (21/104), respectively. The prevalence of IDD was significantly higher in gymnasts with ALV than those without ALV, as determined using the chi-square test. Logistic regression analysis demonstrated a significant association between IDD and ALV (adjusted odds ratio [OR], 6.60; 95% confidence interval [CI], 2.14-20.35). IDD was further grouped by whether it was present in the upper lumbar region (L1-2, L2-3, and L3-4 disks) or in the lower lumbar region (L4-5 and L5-S1 disks). Upper IDD had a greater association with ALV (adjusted OR, 33.17; 95% CI, 7.09-155.25) than did lower IDD (adjusted OR, 6.71; 95% CI, 1.57-28.73).

Conclusion:

In Japanese collegiate gymnasts, ALV is a predictor of IDD, especially in the upper lumbar region.

Clinical Relevance:

Information regarding ALV is important to prevent IDD in Japanese collegiate gymnasts.

Safety and efficacy of an add-on therapy with curcumin phytosome and piperine and/or lipoic acid in subjects with a diagnosis of peripheral neuropathy treated with dexibuprofen

We conducted an 8-week, open, randomized controlled clinical trial on 141 subjects affected by neuropathic pain to investigate the role of an adjunctive therapy added to the administration of dexibuprofen (400 mg twice a day) and based on a multi-ingredient formula (Lipicur), consisting of lipoic acid plus curcumin phytosome and piperine, in patients with a diagnosis of lumbar sciatica, lumbar disk herniation, and/or lumbar canal stenosis (96 subjects), or with carpal tunnel syndrome (45 subjects). A total of 135 participants completed the study. Treatment with the multi-ingredient formula (Lipicur) reduced neuropathic pain by more than 66% in both conditions (subjects with lumbar sciatica and with carpal tunnel syndrome), and these reductions were statistically significant. Moreover, the treatment reduced dexibuprofen use by about 40%. An add-on therapy with only lipoic acid has not shown any significant results. On the basis of its safety and efficacy, Lipicur could be considered an effective complementary therapy to be added to conventional treatments to achieve better efficacy in reducing neuropathic pain.

The molecular basis of intervertebral disc degeneration

BACKGROUND

Intervertebral disc (IVD) degeneration remains a clinically important condition for which treatment is costly and relatively ineffective. The molecular basis of degenerative disc disease has been an intense focus of research recently, which has greatly increased our understanding of the biology underlying this process.

PURPOSE

To review the current understanding of the molecular basis of disc degeneration.

STUDY DESIGN

Review article.

METHODS

A literature review was performed to identify recent investigations and current knowledge regarding the molecular basis of IVD degeneration.

RESULTS

The unique structural requirements and biochemical properties of the disc contribute to its propensity toward degeneration. Mounting evidence suggests that genetic factors account for up to 75% of individual susceptibility to IVD degeneration, far more than the environmental factors such as occupational exposure or smoking that were previously suspected to figure prominently in this process. Decreased extracellular matrix production, increased production of degradative enzymes, and increased expression of inflammatory cytokines contribute to the loss of structural integrity and accelerate IVD degeneration. Neurovascular ingrowth occurs, in part, because of the changing degenerative phenotype.

CONCLUSIONS

A detailed understanding of the biology of IVD degeneration is essential to the design of therapeutic solutions to treat degenerative discs. Although significant advances have been made in explaining the biologic mediators of disc degeneration, the inhospitable biochemical environment of the IVD remains a challenging environment for biological therapies.

Vitamin D receptor gene and aggrecan gene polymorphisms and the risk of intervertebral disc degeneration - a meta-analysis

BACKGROUND

A series of studies have been conducted to evaluate the associations between vitamin D receptor (VDR) and aggrecan variable numbers of tandem repeat (VNTR) polymorphisms and the risk of intervertebral disc degeneration (IDD), but produced conflicting results.

OBJECTIVE

we performed a meta-analysis to address a more accurate estimation of the associations between the above gene polymorphisms and the risk of IDD.

METHODS

A comprehensive literature search was conducted to identify all the relevant studies. The fixed or random effect model was selected based on the heterogeneity test among studies evaluated using the I(2). Publication bias was estimated using Begg's funnel plots and Egger's regression test.

RESULTS

A total of 9, 5, 3, and 7 studies were finally included in the analyses for the associations between the VDR TaqI (rs731236), FokI (rs2228570), ApaI (rs7975232), or aggrecan VNTR polymorphisms and the risk of IDD, respectively. The combined results showed that none of the VDR (TaqI, FokI, ApaI) polymorphisms were significantly associated with the risk of IDD. In contrast, the alleles with shorter VNTR length was found to significantly increase the risk of IDD (≦25 vs. >25: OR = 1.850, 95%CI 1.477-2.318; ≦23 vs. >23: OR = 1.955, 95%CI 1.41-2.703). Subgroup analysis confirmed the above results. After excluding studies deviated from Hardy-Weinberg equilibrium (HWE) in controls, no other studies were found to significantly influence the pooled effects in each genetic model. No potential publication bias was detected.

CONCLUSION

This meta-analysis suggested that the alleles with shorter VNTR length significantly increased the risk of IDD, while the VDR (TaqI, FokI, ApaI) gene polymorphisms were not significantly associated with the risk of IDD. Since potential confounders could not be ruled out completely, further studies are needed to confirm these results.

Surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs in females: a comparative study of incidence and causative factors and treatment

Background and Objective:

There are various postulated possible causes of surgically symptomatic prolapsed intervertebral discs in the lumbar and sacral regions. They may be acting singularly or collectively. Yet, these factors, which could vary in different environments, have not been satisfactorily confirmed. The intention of this study is to share the experience of the author in the occurrence, possible causative factors, and treatment of surgically symptomatic prolapsed lumbar and sacral intervertebral discs in females, and to compare this experience in Switzerland, Nigeria, and Jamaica using surgery records for a period of over 39 years.

Materials and Methods:

Records of these cases were examined and analyzed with the intent of comparing the frequency of occurrence and possible causative factors of this lesion in some countries.

Results:

There were 60 locations in 51 patients in Basel (Caucasian population only), 4 locations in 1 patient in Imo and Ebonyi States (African population only), and none in Jamaica (mixed population). The patients’ ages ranged from 19 to 71 years in Switzerland, and the only patient in Nigeria was 49 years old.

Conclusion:

The study revealed that surgically treated symptomatic prolapsed lumbar and sacral intervertebral discs in females occurred more in Basel, Switzerland, than in Imo and Ebonyi States of Nigeria and none occurred in Jamaica, West Indies. Racial differences, certain sporting/recreational activities, smoking, and type of profession could have contributed to the development of this disease.

An Association Study of Interleukin 18 Receptor Genes (IL18R1 and IL18RAP) in Lumbar Disc Degeneration

Objectives:

To examine association of candidate genetic variants in structural, inflammatory, matrix modifying, vitamin D receptor genes and variants associated with osteoarthritis, with surgical candidates and surgical patients with lumbar disc degeneration (LDD), in light of their previously reported susceptibility for LDD.

Methods:

Genotyping of 146 Norwegian LDD patients and 188 Norwegian controls was performed for 20 single-nucleotide polymorphisms (SNPs) from collagen, aggrecan, interleukin, VDR, MMP3 and COX2 genes and 7 SNPs from osteoarthritic genes.

Results:

The neighboring genes IL18R1 and IL18RAP polymorphisms (rs2287037 and rs1420100), showed a statistically non-significant risk for developing LDD (OR 1.36 [95 % CI 0.99 – 1.87]; p=0.06 and OR 1.33 [95 % CI 0.98-1.81]; p=0.07). Homozygosity of these risk alleles was associated with LDD (p=0.023 and p=0.027). The non-risk alleles at these SNPs were situated on a haplotype negatively associated with LDD (p=0.008). Carriage of at least one non-risk allele at both loci also reduces the risk of developing LDD (OR 0.51 [95 % CI 0.33-0.80]; p=0.003).

Conclusion:

Our findings support the polygenic nature of LDD and suggest that variation in interleukin 18 receptor genes could affect the risk of severe LDD and associated low back pain.

Cartilage intermediate layer protein (CILP) regulation in intervertebral discs. The effect of age, degeneration, and bone morphogenetic protein-2

STUDY DESIGN

An in vitro study using rabbit intervertebral disc tissue and disc cells.

OBJECTIVE

To evaluate the effects of disc degeneration, age, and bone morphogenetic proteins-2 (BMP-2) on cartilage intermediate layer protein (CILP) expression and elucidate the molecular mechanism by which BMP-2 regulates CILP expression.

SUMMARY OF BACKGROUND DATA

CILP is implicated in several diseases that affect cartilage. The CILP polymorphism acts as a modulator of lumbar disc disease susceptibility. However, regulation of the CILP gene in disc tissue remains poorly understood.

METHODS

Intact discs from young rabbits were punctured to induce disc degeneration. These young rabbits and other older rabbits were used to measure the expression of CILP, proteoglycan, and collagen II using Western blot and real-time PCR. Primary disc cells from the rabbits were treated with rhBMP-2, or siRNAs, and the gene expression was analyzed by Western blot and real-time PCR. The activity of the CILP promoter was measured by using the Dual Luciferase Reporter Assay System.

RESULTS

Our study demonstrates that the intervertebral disc expresses significant levels of CILP and that the expression of CILP increases substantially with increasing age and disc degeneration. In contrast, the expression of proteoglycan and collagen II decrease with increasing age and disc degeneration. BMP-2 induces the expression of CILP protein and stimulates the activity of the CILP promoter in rabbit primary disc cells. The induction of CILP by BMP-2 can be augmented with age. Knockdown of Smad1 by siRNA abolishes the stimulatory effects of BMP-2 on CILP expression in the primary disc cells.

CONCLUSION

Our data demonstrate that disc degeneration, age, and BMP-2 are regulators of the CILP gene. BMP-2 induces CILP expression by activating the Smad1 signal pathway.

Association between single nucleotide polymorphism in collagen IX and intervertebral disc disease in the Indian population

BACKGROUND

Symptomatic intervertebral disc degeneration is being recently reported in younger population, questions the basis of its degenerative etiology. Latest evidences show that genetics play a significant role. Collagen IX, an important constituent of disc, is found to be altered in genetically predisposed individuals. Mutations have been reported in COL9A2 and COL9A3 genes, which encode Collagen IX, in Finnish and various other populations. The purpose of the present study is to test the significance of these genes in the Indian population.

MATERIALS AND METHODS

One hundred proven cases of intervertebral disc disease (IDD) of various regions of spine were selected for the study, along with matched controls. They were tested for the above mentioned alleles by allelic discrimination method with real-time polymerase chain reaction (PCR) study after isolation of DNA from blood sample. Each blood sample was classified into one of the three types - homozygous, heterozygous, and wild (normal) type allele - separately for COL9A2 and COL9A3 genes.

RESULTS

Homozygosity for COL9A2 allelic variation was associated with 100% occurrence of the disease. Heterozygous allele of COL9A2 was significantly higher in the study group (42%) as compared to the control group (17%). In contrast, allelic variation in COL9A3 gene was found to have no significant correlation with disc disease. There was no single patient with homozygous allelic variation for COL9A3, suggesting predominance of COL9A2 variation in the Indian population.

CONCLUSION

This candidate gene strategy approach adds considerably to our knowledge of genetic makeup of Indian populations in relation with disc disease. This study highlights importance of COL9A2 gene variation especially of homozygous variety in contrast to COL9A3 variation in causing disc disease in Indian population.

Structure and biology of the intervertebral disk in health and disease

The intervertebral disks along the spine provide motion and protection against mechanical loading. The 3 structural components, nucleus pulposus, annulus fibrosus, and cartilage endplate, function as a synergistic unit, though each has its own role. The cells within each of these components have distinct origins in development and morphology, producing specific extracellular matrix proteins that are organized into unique architectures fit for intervertebral disk function. This article focuses on various aspects of intervertebral disk biology and disruptions that could lead to diseases such as intervertebral disk degeneration.

Genetics of lumbar disk degeneration: technology, study designs, and risk factors

Lumbar disk degeneration (LDD) is a common musculoskeletal condition. Genetic risk factors have been suggested to play a major role in its cause. This article reviews the main research strategies that have been used to study the genetics of LDD, and the genes that thus far have been identified to influence susceptibility to LDD. With the rapid progress in genomic technologies, further advances in the genetics of LDD are expected in the next few years.

Herpes virus infection can cause intervertebral disc degeneration

It has been proposed that intervertebral disc degeneration might be caused by low-grade infection. The purpose of the present study was to assess the incidence of herpes viruses in intervertebral disc specimens from patients with lumbar disc herniation. A polymerase chain reaction based assay was applied to screen for the DNA of eight different herpes viruses in 16 patients and two controls. DNA of at least one herpes virus was detected in 13 specimens (81.25%). Herpes Simplex Virus type-1 (HSV-1) was the most frequently detected virus (56.25%), followed by Cytomegalovirus (CMV) (37.5%). In two patients, co-infection by both HSV-1 and CMV was detected. All samples, including the control specimens, were negative for Herpes Simplex Virus type-2, Varicella Zoster Virus, Epstein Barr Virus, Human Herpes Viruses 6, 7 and 8. The absence of an acute infection was confirmed both at the serological and mRNA level.

To our knowledge this is the first unequivocal evidence of the presence of herpes virus DNA in intervertebral disc specimens of patients with lumbar disc herniation suggesting the potential role of herpes viruses as a contributing factor to the pathogenesis of degenerative disc disease.

On the quantitative relationships between individual/occupational risk factors and low back pain prevalence using nonparametric approaches

OBJECTIVES

To explore dual quantitative relationships between low back pain (LBP) prevalence and different individual and occupational risk factors, and detect the most important ones which can be used as weighted input data in LBP prediction diagnosis models, providing effective tools to help with the implementation of protection and prevention strategies among hospital staff.

METHODS

Fourteen predictor individual risk factors (e.g., age, gender, body mass index BMI [kg/m(2)], domestic activity, etc.) and 17 occupational risk factors (e.g., job status, standing hours/day, sufficient break time, job dissatisfaction, etc.) were collected using self-reported questionnaire among the staff of Sacré-Coeur hospital - Lebanon (used as a case study), and correlated with LBP prevalence using Kendall's tau-b bivariate nonparametric approaches.

RESULTS

This study indicates that among the investigated occupational risk factors, job status, working hours/day, and standing hours/day are the most influencing on LBP prevalence (highly correlated with other factors at 1 and 5% confidence levels). It also shows that strong positive (between 0.25 and 0.65)/negative (from -0.38 to -0.26) statistical correlations to LBP prevalence exist between these risk occupational factors and working days/week, sitting hours/day, job stress, job dissatisfaction, children care, and car driving. The weekly hours of domestic activity, the staff height, and gender type have proven also to be the strongest individual factors in aggravating LBP disease. These individual factors are highly correlated at 1% significance level (ranging between 0.28 and 0.49 for positive correlations, and from -0.49 to -0.25 for negative ones) to children care, weight, extra professional activity, and use of handling techniques.

CONCLUSIONS

These obtained bivariate correlations can be used successfully by expert physicians in their decision making for LBP diagnosis.

Evidence for an inherited predisposition to lumbar disc disease

BACKGROUND

A genetic predisposition for the development of symptomatic lumbar disc disease has been suggested by several twin sibling studies and subsequent genetic marker studies. The purpose of the present study was to define population-based familial clustering among individuals with a diagnosis of, or treated for, lumbar disc herniation or disc degeneration.

METHODS

The Utah Population Database allows analysis of combined health and genealogic data for over one million Utah residents. We used the International Classification of Diseases, Ninth Revision, diagnosis codes entered in patient records to identify patients with a diagnosis of either lumbar disc herniation or lumbar disc degeneration and genealogic data. The hypothesis of excess relatedness (familial clustering) was tested with use of the Genealogical Index of Familiality, which compares the average relatedness of affected individuals with expected population relatedness. Relative risks in relatives were estimated by comparing rates of disease in relatives with expected population rates (estimated from the relatives of matched controls). This methodology has been previously reported for other disease conditions but not for spinal diseases.

RESULTS

The Genealogical Index of Familiality test for 1264 patients with lumbar disc disease showed a significant excess relatedness (p < 0.001). Relative risk in relatives was significantly elevated in both first-degree (relative risk, 4.15; p < 0.001) and third-degree relatives (relative risk, 1.46; p = 0.027).

CONCLUSIONS

Excess relatedness of affected individuals and elevated risks to both near and distant relatives was observed, strongly supporting a heritable contribution to the development of symptomatic lumbar disc disease.