Ossification of the ligamentum flavum with myelopathy

Ossification of the Ligamentum Flavum in a Nineteenth-Century Skeletal Population Sample from Ireland: Using Bioarchaeology to Reveal a Neglected Spine Pathology

Ossification of the ligamentum flavum of the spine (OLF) is rarely reported in individuals of European ancestry. It has, however, been observed in archaeological skeletons from Europe. The aim of this study was to revisit OLF rates, utilising a mid-nineteenth-century skeletal sample from Ireland. The hypothesis was that the OLF prevalence rate was similar to studies on non-Europeans. Spines from 345 individuals were analysed, and the extent of OLF recorded on the cranial and caudal attachment sites of each vertebra using the following classification system: Grade 0 (no change); Grade 1 (<2 mm); Grade 2 (2–4 mm); Grade 3 (≥4 mm). OLF was observed at prevalence rates of 83.6%. There was no disparity in prevalence based on sex, except for individuals aged 36–45 years at death in which the male rate was higher. Advancing age was a determining factor in the OLF occurrence with an onset in young adulthood (18–25 years), and most severe grades occurring over the age of 25 years. OLF coincides with spinal osteoarthritis, spondylosis deformans and Schmorl’s nodes in both sexes, and with intervertebral osteochondrosis in females. The results of this study indicate that OLF is likely to be an understudied rather than rare condition in European populations.

Surgical treatments of myelopathy caused by cervical ligamentum flavum ossification

OBJECTIVE

To present a small case series reporting the outcomes of surgical treatment for myelopathy caused by cervical ossification of the ligamentum flavum (OLF).

METHODS

The authors assessed 15 cases of myelopathy caused by cervical OLF. Patients were eight women and seven men 37-75 years old (mean age 59.7 years). All patients underwent bilateral laminectomy, and the lesions were removed. The decompression range was confined within the medial sides of the bilateral facets and within the involved segments. Intraoperative specimens were examined histologically to confirm the diagnosis. During the operation, the extent of adherence of the lesions to the dura was recorded. The patients were followed for 3-70 months. Neurofunctional improvements were evaluated with the Japanese Orthopaedic Association (JOA) score.

RESULTS

Definite adherences were present in 67.7% of all cases. JOA score showed a 71.5% improvement after operation from a preoperative score of 5-8 (mean 6.4) to a postoperative score of 10-14 (mean 13.5). The operative outcomes were satisfactory without extensive decompression of adjacent segments.

CONCLUSIONS

A high rate of adherence to the dura was observed in patients with myelopathy caused by cervical OLF. Bilateral laminectomy and removal of the lesions, without extensive decompression of adjacent segments, provides an optimistic prognosis.

Ossification of the ligamentum flavum in a Caucasian man

Abnormal ossification of spinal ligaments is a well-known cause of myelopathy in East Asian populations, with ossification of the ligamentum flavum (OLF) and the posterior longitudinal ligament being the most prevalent. In Caucasian populations, OLF is rare, and there has been only 1 documented case of the disease affecting more than 5 spinal levels. In this report, the authors describe the clinical presentation, imaging characteristics, and management of the second published case of a Caucasian man with OLF affecting almost the entire thoracic spine. The literature is then reviewed with regard to OLF epidemiology, pathogenesis, presentation, and treatment.

Symptomatic ossification of the ligamentum flavum: a clinical series from the French Antilles

STUDY DESIGN

A series of 14 patients from the French Antilles treated for ossification of the ligamentum flavum (OLF).

OBJECTIVES

To describe the clinical and radiologic aspects, as well as disease course in a group of Caribbean patients. Also describe the use of sagittal computerized tomography (CT) reconstructions to distinguish OLF from calcification of the ligamenta flava.

SUMMARY OF BACKGROUND DATA

OLF is a rare disease described almost exclusively in Japanese patients. Only rarely are patients of African descent affected. No series of OLF in African American or African Caribbean subjects has previously been published.

METHODS

A retrospective study of 14 consecutive patients, including 7 men and 7 women (mean age, 66.8 years), was conducted from 1996 to 2003. Diagnosis in each case was established using CT. Magnetic resonance imaging was also performed in every case. For the 11 patients treated surgically, pathology studies were performed.

RESULTS

Walking difficulties were the most common presenting complaint. A picture of spastic paraparesis associated with sphincter dysfunction was the most common finding on initial examination. In each case, CT provided sufficient information to establish a diagnosis of OLF, while magnetic resonance imaging was helpful for showing spinal cord involvement. In most of the patients, OLF was located in the lower thoracic spine. Surgical decompression through a posterior approach resulted in regression of symptoms in all 11 patients treated surgically.

CONCLUSIONS

This study is the first reported series of OLF in a group of Caribbean patients. The disease appears to be underreported in the African Caribbean population. OLF can lead to debilitating thoracic myelopathy. Surgery is frequently indicated and achieves favorable results.

Ossified ligamentum flavum of the atlantoaxial region

A 30-year-old male presented complaining of a six-month history of progressive weakness and paraesthesia in all four limbs. Symptoms occurred following moderately severe neck trauma. Investigations revealed ossification of the ligamentum flavum (OLF) between the atlas and axis, with marked cord compression. The patient showed remarkable neurological recovery following excision of the OLF. OLF causing cord compression is rare and has never been reported in the atlantoaxial region.

Cough induced by ossification of the ligamentum flavum in the high cervical spine

✓ The authors report a very rare case of high cervical ossification of the ligamentum flavum (OLF) in a 40-year-old woman who developed an intractable cough after a traffic accident. The patient's symptoms subsided immediately after decompressive laminectomy and removal of the lesion. To the authors' knowledge, this is the first reported case of high cervical OLF in a patient who presented with a cough. The pathophysiological mechanism underlying the cough was determined to be symptomatic of high cervical spine OLF.

Thoracic myelopathy caused by ossification of the ligamentum flavum: a report of 18 cases

OBJECT

Thoracic myelopathy caused by ossification of the ligamentum flavum (OLF) is a rare entity, most evident in Japan. The authors studied the clinical manifestations, radiological aspects, surgical treatment, and pathogenesis of this disease.

METHODS

Eighteen patients with OLF-induced thoracic myelopathy underwent laminectomy. The severity of myelopathy varied. Complete paraplegia was seen in three cases. Compression of the upper and middle third of the thoracic spine was evident in six cases and of the lower third in 12 cases. Multilevel OLF was demonstrated in 13 cases. In most cases, the ossified ligamentum flavum appears as a V-shaped lesion on computerized tomography and magnetic resonance images. In all patients the diameter of the posterior spinal canal, already narrowed, was further exacerbated by the OLF. Laminectomy was limited to the levels of compression, and the ligamentum flavum was resected in all cases. The symptoms and signs improved in 13 cases and stabilized in four cases. In one case symptoms recurred as a result of ossified lesions forming at other sites. Histological examination showed that the mode of development of the ossified ligaments was endochondral ossification.

CONCLUSIONS

Reports of OLF-induced myelopathy are rare and mainly described in Japan. The incidence also seems high in North Africa. An early laminectomy limited to the level of compression is recommended. Ossified ligamentum flavum is different from the calcification of the ligamentum flavum, which is due to crystal deposits.

Surgical treatment for thoracic spinal stenosis

OBJECTIVES

To describe the underlying causes, surgical results and prognostic factors in thoracic stenosis causing myelopathy.

METHODS

The underlying causes and surgical results were analyzed retrospectively in 28 cases of thoracic spinal stenosis which caused myelopathy. Degenerative spondylosis was the most common cause, and three cases were associated with systemic diseases. Decompressive laminectomy was performed in 24 cases, anterior decompression in five cases, and combined decompression in one case. Ossification of ligamentum flavum was found in 18 cases, facet hypertrophy in 13, ossification of posterior longitudinal ligament in six, and ventral spur in four. Postoperatively 16 patients improved and four patients worsened. Follow-up ranged from 2 months to 5 years and 8 months). Statistical analysis was performed using a chi(2) test to investigate the relationship between subjects. Multivariant analysis (general linear model) was used to determine the factors which influence surgical outcome.

RESULTS

There were neurological improvements in 16 patients, in whom Nurick grade changed from 3.3 preoperatively to 1.8 postoperatively. Eight patients showed no significant change in functional grade and four patients deteriorated after decompressive laminectomy. The group of which initial symptom duration was less than 2 years showed better results (P=0.006). The group with sufficient decompression and no additional proximal stenosis had better treatment outcome (P=0.005, P=0.002).

CONCLUSION

Chronic severe myelopathy caused by thoracic spinal stenosis can be reversible with appropriate decompression. Surgical outcome was dependent on initial symptom duration, sufficient decompression and presence of additional proximal stenosis.

SPONSORSHIP

This study was supported by a grant No. 02-1997-071-0 from the Seoul National University Hospital Research Fund.