Prevalence and characteristics of thoracic ossification of the posterior longitudinal ligament in 3299 Black patients: a cross-sectional study of a prospectively registered database

OBJECTIVES

To the best of our knowledge, the prevalence of thoracic ossification of the posterior longitudinal ligament (T-OPLL) in the Black population has never been studied and is still unknown. The purpose of this study was to examine the prevalence and characteristics of T-OPLL in the Black patients.

METHODS

This is a cross-sectional study. All patients who underwent chest CT for the trauma screening and whose race was classified as 'Black' on the questionnaire were recruited in the study from March 2019 to March 2020. Demographic data, including age, sex, body mass index (BMI) and presence of diabetes mellitus (DM), were recorded. T-OPLL was defined as ectopic OPLL of more than 2 mm thickness in the axial plane image of the CT scan. The prevalence and characteristics of T-OPLL, and the association of T-OPLL with BMI and DM were evaluated.

RESULTS

A total of 3299 Black patients (1507 women and 1792 men) were included for the analysis. The prevalence of T-OPLL was 1.5% (50 patients), with 2.4% for females and 0.8% for males. The highest prevalence was observed in patients at the age of 70 years (3.8%). Thickness of T-OPLL was between 2 and 3 mm in 46% (23/50) of the patients, and the largest thickness was 6.1 mm. T-OPLL was significantly associated with female sex and the presence of DM.

CONCLUSIONS

The prevalence of T-OPLL was 1.5% in the 3299 Black patients who underwent chest CT for the trauma screening, with 2.4% for females and 0.8% for males.

Global Trends Of The Researches On Ossification Of Posterior Longitudinal Ligament In Thoracic Spine: A Bibliometric And Visualization Study

STUDY DESIGN

Bibliometric analysis OBJECTIVE: Thoracic ossification of the posterior longitudinal ligament (TOPLL) was a rare but intractable disease, and was the second leading cause of thoracic myelopathy. This study aimed to illustrate the overall knowledge structure, and development trends of TOPLL, using a bibliometric analysis and newly developed visualization tools.

METHODS

Research datasets were acquired from the Web of Science. The literature search was also limited to articles that were published until Oct 30, 2021. VOS viewer and Citespace software was provided to analyze the data and generate visualization knowledge maps. Annual trend of publications, distribution, H-Index status, co-authorship status and research hotspots were analyzed.

RESULTS

206 publications met the requirement. Japan published most papers (92), both total citations (1574) and H-index (24) ranked first of all the countries. The most productive organizations were Peking University (22). The most productive authors were Yamazaki M (18). The most productive journals were Spine (33). Diagnosis and treatment on the accuracy of surgical segments, prognosis of patients, and gene research were the research hotspots in the recent years.

CONCLUSION

The study showed an upward trend with a stable rise in recent years. Japan is country with the highest productivity, not only in quality, but also in quantity. Peking University and Spine have been the largest contributor. Indeed, this study provides great insights to the growth and development of TOPLL. Moreover, it will contribute to the growth of the international frontier.

Efficacy of Intraoperative Neuromonitoring Using Transcranial Motor-Evoked Potentials for Degenerative Cervical Myelopathy: A Prospective Multicenter Study by the Monitoring Committee of the Japanese Society for Spine Surgery and Related Research

STUDY DESIGN

A prospective multicenter observational study.

OBJECTIVE

To elucidate the efficacy of transcranial motor-evoked potentials (Tc(E)-MEPs) in degenerative cervical myelopathy (DCM) surgery by comparing cervical spondylotic myelopathy (CSM) to cervical ossification of the posterior longitudinal ligament (OPLL) and investigate the timing of Tc(E)-MEPs alerts and types of interventions affecting surgical outcomes.

SUMMARY OF BACKGROUND DATA

Although CSM and OPLL are the most commonly encountered diseases of DCM, the benefits of Tc(E)-MEPs for DCM remain unclear and comparisons of these two diseases have not yet been conducted.

METHODS

We examined the results of Tc(E)-MEPs from 1176 DCM cases (840 CSM /336 OPLL) and compared patients background by disease, preoperative motor deficits, and the type of surgical procedure. We also assessed the efficacy of interventions based on Tc(E)-MEPs alerts. Tc(E)-MEPs alerts were defined as an amplitude reduction of more than 70% below the control waveform. Rescue cases were defined as those in which waveform recovery was achieved after interventions in response to alerts and no postoperative paralysis.

RESULTS

Overall sensitivity was 57.1%, and sensitivity was higher with OPLL (71.4%) than with CSM (42.9%). The sensitivity of acute onset segmental palsy including C5 palsy was 40% (OPLL/CSM: 66.7%/0%) whereas that of lower limb palsy was 100%. The most common timing of Tc(E)-MEPs alerts was during decompression (63.16%), followed by screw insertion (15.79%). The overall rescue rate was 57.9% (OPLL/CSM: 58.3%/57.1%).

CONCLUSION

Since Tc(E)-MEPs are excellent for detecting long tract injuries, surgeons need to consider appropriate interventions in response to alerts. The detection of acute onset segmental palsy by Tc(E)-MEPs was partially possible with OPLL, but may still be difficult with CSM. The rescue rate was higher than 50% and appropriate interventions may have prevented postoperative neurological complications.Level of Evidence: 3.

Risk factors for the development of degenerative cervical myelopathy: a review of the literature

Degenerative cervical myelopathy (DCM) encompasses various pathological conditions causing spinal cord (SC) impairment, including spondylosis (multiple level degeneration), degenerative disc disease (DDD), ossification of the posterior longitudinal ligament (OPLL), and ossification of the ligamentum flavum (OLF). It is considered the most common cause of SC dysfunction among the adult population. The degenerative phenomena of DDD, spondylosis, OPLL and OLF, is likely due to both inter-related and distinct factors. Age, cervical alignment, and range of motion, as well as congenital factors such as cervical cord-canal mismatch due to congenital stenosis, Klippel-Feil, Ehler-Danlos, and Down syndromes have been previously reported as potential factors of risk for DCM. The correlation between some comorbidities, such as rheumatoid arthritis and movement disorders (Parkinson disease and cervical dystonia) and DCM, has also been reported; however, the literature remains scare. Other patient-specific factors including smoking, participation in contact sports, regular heavy load carrying on the head, and occupation (e.g. astronauts) have also been suggested as potential risk of myelopathy development. Most of the identified DCM risk factors remain poorly studied however. Further researches will be necessary to strengthen the current knowledge on the subject, especially concerning physical labors in order to identify patients at risk and to develop an effective treatment strategy for preventing this increasing prevalent disorder.

Open-door Laminoplasty for Multilevel Cervical Spondylotic Myelopathy and Ossification of the Posterior Longitudinal Ligament (OPLL) using Titanium Reconstruction Miniplate and Screws

To review outcome of 25 patients who underwent open-door cervical laminoplasty for multilevel cervical spondylotic myelopathy (MCSM) and ossification of the posterior longitudinal ligament (OPLL) using titanium reconstruction miniplate and screws. Records of 18 men and 7 women aged 35 to 78 (mean, 62.6) years were reviewed retrospectively from October 2009 and October 2014 at Bangabandhu Sheikh Mujib Medical University (BSMMU) and in our private settings, Dhaka, Bangladesh. Four patients had 5 levels (C3-C7), 21 patients had 4 levels (C3-C6) decompression and 3 patients (12%) performed foraminotomies. A total of 104 laminae were opened, all of them were fixed with a titanium reconstruction miniplates. In 21 patients, a 20-hole titanium miniplate bent to the contour of a lamina was used and fixed into 4 laminae and 4 patients fixed in 5 laminae levels. In most patients, screw fixation was unicortical and no spacer or bone graft was used. Demographic and surgical data were collected and clinical outcomes were assessed with neck pain score, neck disability index and Nurick's grading. Outcome analysis was done using Odom's criteria. The mean follow-up duration was 1.8 (range, 1-5) years. Diagnoses were MCSM (n=20), OPLL (n=5). Mean estimated blood loss (EBL) was 120ml (range: 50-200), mean surgery time was 153 min (range: 75-240). Following Nurick's grading, 23 patients (92%) improved, 2 (08%) had the same Nurick grade. No intraoperative complications were noted and average hospital stay was 6.12 days (range: 5 to 9). Significance improvements in overall NDI scores occurred at 1 year follow up (p<0.002). Radiographic evaluation showed an increase in the mean sagittal diameter from 13.3mm at pretreatment to 19.4mm post surgery. Two patients developed transient C5 palsy. Open-door Laminoplasty technique is safe, easy and achieves a good canal expansion and neurological recovery and can be used as an alternative treatment for cases of MCSM and OPLL patients without instability.

Prevalence of complications after surgery in treatment for cervical compressive myelopathy: A meta-analysis for last decade

PURPOSE

We aim to perform a meta-analysis on prevalence of all kinds of operation-related complications following surgery treating cervical compressive myelopathy (CCM) and to provide reference for surgeons making surgical plan.

METHODS

An extensive search of literature was performed in PubMed/MEDLINE, Embase, the Cochrane library, CNKI, and WANFANG databases on incidence of operation-related complications from January 2007 to November 2016. Data was calculated and data analysis was conducted with STATA 12.0 and Revman 5.3.

RESULTS

A total of 107 studies included 1705 of 8612 patients (20.1%, 95% CI 17.3%-22.8%) on overall complications. The incidence of C5 plasy, cerebrospinal fluid (CSF), infection, axial pain, dysphagia, hoarseness, fusion failure, graft subsidence, graft dislodgment, and epidural hematoma is 5.3% (95% CI 4.3%-6.2%), 1.9% (95% CI 1.3%-2.4%), 2.8% (95% CI 1.7%-4.0%), 15.6% (95% CI 11.7%-19.5%), 16.8% (95% CI 13.6%-19.9%), 4.0% (95% CI 2.3%-5.7%), 2.6% (95% CI 0.2%-4.9%), 3.7% (95% CI 2.0%-5.5%), 3.4% (95% CI 2.0%-4.8%), 1.1% (95% CI 0.7%-1.5%), respectively. Patients with ossification of posterior longitudinal ligament (OPLL) (6.3%) had a higher prevalence of C5 plasy than those with cervical spondylotic myelopathy (CSM) (4.1%), and a similar trend in CSF (12.2% vs 0.9%). Individuals after laminectomy and fusion (LF) had highest rate of C5 plasy (15.2%), while those who underwent anterior cervical discectomy and fusion (ACDF) had the lowest prevalence (2.0%). Compared with patients after other surgical options, individuals after anterior cervical corpectomy and fusion (ACCF) have the highest rate of CSF (4.2%), infection (14.2%), and epidural hematoma (3.1%). Patients after ACDF (4.8%) had a higher prevalence of hoarseness than those with ACCF (3.0%), and a similar trend for dysphagia between anterior corpectomy combined with discectomy (ACCDF) and ACCF (16.8% vs 9.9%).

CONCLUSIONS

Based on our meta-analysis, patients with OPLL have a higher incidence of C5 palsy and CSF. Patients after LF have a higher incidence of C5 palsy, ACCDF have a higher incidence of dysphagia, ACCF have a higher incidence of CSF and infection and ACDF have a higher incidence of hoarseness. These figures may be useful in the estimation of the probability of complications following cervical surgery.

Calcific deposits on degraded shunt catheters: long-term follow-up of V-P shunts and late complications in three cases

OBJECT

Three cases with late complications and nine cases without late complications are presented to demonstrate the long-term results of ventriculoperitoneal (V-P) shunting, particularly those concerning degradation and mineral deposits of shunt catheters.

METHODS

Plain X-rays were taken in every case to detect any calcification. The catheters removed following late complications were examined in a scanning electron microscope (SEM). Spectroscopy and conventional histology were also performed.

CONCLUSION

Routine histology, spectroscopy, and SEM revealed that the mineral deposits consisted of hydroxyapatite. Plain X-ray and operative findings showed that the most extensive calcification was present in the neck, where the catheters were subject to heavy mechanical stress. No calcification was detected on catheters that did not contain barium particles. Our findings indicate that mechanical stress contributes to the process of degradation, and that barium sulfate admixed with silicone during the manufacturing process might accelerate late complications owing to the formation of cracks in the catheters and by enhancing the nucleation rate.