Effects of ethane-1-hydroxy-1,1-diphosphonate on ossification of the posterior longitudinal ligament in Zucker fatty rats

Genetic insights into ossification of the posterior longitudinal ligament of the spine

Ossification of the posterior longitudinal ligament of the spine (OPLL) is an intractable disease leading to severe neurological deficits. Its etiology and pathogenesis are primarily unknown. The relationship between OPLL and comorbidities, especially type 2 diabetes (T2D) and high body mass index (BMI), has been the focus of attention; however, no trait has been proven to have a causal relationship. We conducted a meta-analysis of genome-wide association studies (GWASs) using 22,016 Japanese individuals and identified 14 significant loci, 8 of which were previously unreported. We then conducted a gene-based association analysis and a transcriptome-wide Mendelian randomization approach and identified three candidate genes for each. Partitioning heritability enrichment analyses observed significant enrichment of the polygenic signals in the active enhancers of the connective/bone cell group, especially H3K27ac in chondrogenic differentiation cells, as well as the immune/hematopoietic cell group. Single-cell RNA sequencing of Achilles tendon cells from a mouse Achilles tendon ossification model confirmed the expression of genes in GWAS and post-GWAS analyses in mesenchymal and immune cells. Genetic correlations with 96 complex traits showed positive correlations with T2D and BMI and a negative correlation with cerebral aneurysm. Mendelian randomization analysis demonstrated a significant causal effect of increased BMI and high bone mineral density on OPLL. We evaluated the clinical images in detail and classified OPLL into cervical, thoracic, and the other types. GWAS subanalyses identified subtype-specific signals. A polygenic risk score for BMI demonstrated that the effect of BMI was particularly strong in thoracic OPLL. Our study provides genetic insight into the etiology and pathogenesis of OPLL and is expected to serve as a basis for future treatment development.

Surgical treatment of anterior cervical osteophytes causing dysphagia

PURPOSE

Dysphagia due to anterior cervical osteophytes is a rare condition. However, it can become serious enough to permanently impair the quality of life up to making normal food intake impossible. If conservative treatment fails, there is the option of surgical resection of the osteophytes. The objective of this study was to assess the outcomes of resections of anterior cervical osteophytes causing spondylogenic dysphagia, taking literature into consideration.

METHOD

Resection of anterior cervical osteophytes using a standard anterior approach was performed in 14 consecutive patients with spondylogenic dysphagia between 2009 and 2015. Indomethacin or radiation was used to prevent recurrence. Imaging and clinical data were collected in follow-up examinations over an average of 50 months.

RESULTS

The osteophytes were sufficiently resected in all cases. Anterior plates were placed in three patients due to pronounced segmental mobility. Five patients were given recurrence prevention in the form of indomethacin, nine with radiation. One patient required revision surgery for a hematoma. No other serious complications were observed. All patients had significant improvement of their symptoms. No recurrences or signs of increasing instability were found during the follow-up period.

CONCLUSION

When conservative treatment fails, surgical resection of cervical osteophytes is a sufficient method for treating spondylogenic dysphagia. High patient satisfaction and improvement of the quality of life are achieved with a low complication rate. Routine additional stabilization has been discussed as recurrence prevention. Prophylaxis using indomethacin or radiation, known primarily from hip replacement, also appears to be an option.

Progressive dysphagia and dysphonia secondary to DISH-related anterior cervical osteophytes: A case report

Background:

Dysphagia due to diffuse idiopathic skeletal hyperostosis (DISH)-related anterior cervical osteophytes is not uncommon. However, this rarely leads to dysphonia and/or dysphagia along with life- threatening airway obstruction requiring emergency tracheotomy.

Case Description:

A 56-year-old male presented with progressive dysphagia and dysphonia secondary to DISH-related anterior osteophytes at the C3–C4 and C4–C5 levels. The barium swallow, X-ray, magnetic resonance imaging, and computed tomography scans confirmed the presence of DISH. Utilizing an anterior cervical approach, a large beak-like osteophyte was successfully removed, while preserving the anterior annulus. After clinic-radiological improvement, the patient was discharged with a soft cervical collar and nonsteroidal anti-inflammatory drug (NSAID).

Conclusion:

Large anterior osteophytes in Forestier disease/DISH may cause dysphagia and dysphonia. Direct anterior resection of these lesions yields excellent results as long as other etiologies for such symptoms have been ruled out.

Histological evaluation of symptomatic ossification of the anterior longitudinal ligament treated with etidronate disodium: a case report

Background

Here we report the first autopsied case involving pathological examination after two resections of symptomatic ossification of the anterior longitudinal ligament with anterior osteophytes and etidronate treatment with more than 8 years of follow-up.

Case presentation

A 51-year-old Japanese man complained of severe dysphagia due to esophageal compression by ossification of his anterior longitudinal ligament with anterior cervical osteophytes. Although surgical removal of the anterior cervical osteophytes was performed following etidronate treatment (800 mg/day for 6 months), dysphagia occurred secondary to recurrent ossification of his anterior longitudinal ligament with anterior osteophytes 7 years after the initial resection. A second resection of the anterior cervical osteophytes was performed, and cyclic administration of etidronate disodium (1000 mg/day, 3-month administration and 3-month cessation) did not result in re-outgrowth of ossification of his anterior longitudinal ligament with anterior osteophytes. At 1 year and 6 months after the second surgery, he suddenly died. The pathological findings associated with the ossification of his anterior longitudinal ligament during etidronate therapy showed no recurrence of ossification of the anterior longitudinal ligament with anterior osteophytes.

Conclusion

A recurrence of ossification of the anterior longitudinal ligament with anterior osteophytes formation, which caused dysphagia, was not observed with the cyclic administration of etidronate disodium at a dose of 1000 mg/day every 3 months for a period of 1 year and 5 months in the present case.