Spinal cord compression caused by unusual location and extension of ossified ligamenta flava in a Caucasian male. A case report and literature review

The Symptomatic Calcification and Ossification of the Ligamentum Flavum in the Spine: Our Experience and Review of the Literature

INTRODUCTION

We report our experience regarding the clinical features and pathological findings of the calcification of the ligamentum flavum (CLF) and ossification of the ligamentum flavum (OLF) in the spine. In addition, we reviewed the previous studies on CLF and OLF to enhance the understanding of these conditions.

MATERIALS AND METHODS

We compared the clinical, radiological, and histopathological features of CLF and OLF.

RESULTS

In CLF, a computed tomography (CT) scan showed egg-shaped or speck-like calcification in the ligamentum flavum. Magnetic resonance (MR) imaging demonstrated spinal cord compression due to a thickened ligamentum flavum, which appeared as a low-intensity mass. Pathological findings demonstrated fused islands of calcification resembling sand-like calcification. In OLF, CT showed beak-like ossification extending into the intervertebral foramen. MR imaging demonstrated spinal cord compression by a low-intensity mass. Pathological findings revealed laminar ossification of LF with chondrocytes near the calcification and laminar hyaline cartilage.

CONCLUSIONS

CLF and OLF appear to be distinct entities based on their clinical, neuroradiological, histopathological, and pathogenetic features. We suggest that the causes of CLF include both metabolic and dystrophic factors, while the pathogenesis of OLF is characterized by enchondral ossification induced by a genetic cascade triggered by shearing/tension stress.

Genetics of Diffuse Idiopathic Skeletal Hyperostosis and Ossification of the Spinal Ligaments

PURPOSE OF REVIEW

The study aims to provide updated information on the genetic factors associated with the diagnoses 'Diffuse Idiopathic Skeletal Hyperostosis' (DISH), 'Ossification of the Posterior Longitudinal Ligament' (OPLL), and in patients with spinal ligament ossification.

RECENT FINDINGS

Recent studies have advanced our knowledge of genetic factors associated with DISH, OPLL, and other spinal ossification (ossification of the anterior longitudinal ligament [OALL] and the yellow ligament [OYL]). Several case studies of individuals afflicted with monogenic disorders, such as X-linked hypophosphatemia (XLH), demonstrate the strong association of fibroblast growth factor 23-related hypophosphatemia with OPLL, suggesting that pathogenic variants in PHEX, ENPP1, and DMP1 are associated with FGF23-phosphate wasting phenotype and strong genetic factors placing patients at risk for OPLL. Moreover, emerging evidence demonstrates that heterozygous and compound heterozygous ENPP1 pathogenic variants inducing 'Autosomal Recessive Hypophosphatemic Rickets Type 2' (ARHR2) also place patients at risk for DISH and OPLL, possibly due to the loss of inhibitory plasma pyrophosphate (PPi) which suppresses ectopic calcification and enthesis mineralization. Our findings emphasize the importance of genetic and plasma biomarker screening in the clinical evaluation of DISH and OPLL patients, with plasma PPi constituting an important new biomarker for the identification of DISH and OPLL patients whose disease course may be responsive to ENPP1 enzyme therapy, now in clinical trials for rare calcification disorders.

Clinical efficacy of single intraoperative 500 mg methylprednisolone management therapy for thoracic myelopathy caused by ossification of the ligamentum flavum

Background

The objective of our study was to compare clinical outcome and postoperative complications between patients with thoracic myelopathy caused by ossification of the ligamentum flavum (OLF) treated with and without intraoperative methylprednisolone (MP).

Methods

This retrospective study enrolled 101 patients who underwent posterior approach surgery for OLF and were followed up at least 1 year. Patients were divided into two groups according to MP use in the operation: MP group (n = 47) and non-MP group (n = 54). Clinical outcomes and complications were evaluated before and after operation and at the last follow-up.

Results

Significant differences were found in modified Japanese Orthopedics Association (mJOA) scores and proportion of Frankel grade (A-C) between the two groups immediately after surgery and at 2-week follow-up. No significant differences were found between the two groups in mJOA score before operation and at the final follow-up. Moreover, no significant differences were observed in recovery rate according to mJOA score at any time points, and there was no significant difference in the proportion of Frankel grade (A-C) between the two groups at final follow-up. There were 13 documented infections: 10 in the MP group and 3 in the non-MP group (P = 0.034).

Conclusion

Management therapy with intraoperative 500 mg MP showed better recovery of nerve function within 2 weeks in patients with thoracic myelopathy caused by OLF compared with those did not receive MP. However, long-term follow-up results showed that there was no significant difference in neurological recovery between patients with intraoperative MP or not. Moreover, intraoperative MP increased the rate of wound infection.

Large Compressive Pseudomeningocele Causing Early Major Neurologic Deficit After Spinal Surgery

STUDY DESIGN

Retrospective review.

OBJECTIVES

Large compressive pseudomeningocele causing a major neurologic deficit is a very rare complication that is not well described in the existing literature.

METHODS

Institutional review board consent was obtained to study 2552 consecutive extradural spinal surgical cases performed by a single senior spinal surgeon during a 10-year period. The surgeon's database for the decade was retrospectively reviewed and 3 cases involving postoperative major neurologic deficits caused by large compressive pseudomeningocele were identified.

RESULTS

The incidence of postoperative compressive pseudomeningocele causing major neurologic deficit was 0.12% (3/2552) per decade of spinal surgery with approximately 1.3% of cases incurring incidental durotomy. Average age of the patients was 57 years (range 45-78). One patient had posterior cervical spine surgery, and 2 patients had posterior lumbar surgery. All 3 patients had intraoperative incidental durotomy repaired during their index procedure. Large compressive pseudomeningocele causing major neurologic deficit occurred in the early 2-week postoperative period in all patients and was clearly identified on postoperative magnetic resonance imaging. All 3 patients were treated with emergent decompression and repair of the dural defect. All patients recovered neurologic function after revision surgery.

CONCLUSIONS

Incidental durotomy and repair causing a large compressive pseudomeningocele after spine surgery is a rare and potentially devastating event. Early postoperative magnetic resonance imaging assists in the diagnosis. Emergent decompression combined with revision dural repair surgery may result in improved outcomes. Surgeons should be cognizant of this rare cause of early postoperative major neurologic deficit in patients who had previous dural repair.

Surgical Technique for Decompression of Severe Thoracic Myelopathy due to Tuberous Ossification of Ligamentum Flavum

STUDY DESIGN

Retrospective review.

OBJECTIVE

To describe a safe surgical procedure, en bloc resection of the posterior wall of the thoracic canal, for the decompression of severe thoracic myelopathy caused by tuberous ossification of the ligamentum flavum (OLF).

SUMMARY OF BACKGROUND DATA

OLF has been widely recognized as a cause of thoracic myelopathy in East Asia. Surgical decompression of thoracic myelopathy caused by OLF is technically demanding. Although several surgical decompression procedures have been described, acute neurological deterioration is common.

MATERIALS AND METHODS

Eighteen patients with severe thoracic myelopathy caused by tuberous OLF underwent posterior decompression via segmental en bloc resection of the posterior wall of the thoracic canal. The ossified ligamentum flavum, laminae, and partial facet joints of each segment were resected en bloc. Ossified dura mater was removed if present. Posterior fixation with pedicle screws was followed by lateral bone graft fusion.

RESULTS

The mean preoperative modified Japanese Orthopaedic Association score (total score, 11) was 4.1 (range, 2-5). Postoperatively, no neurological deterioration occurred, and all patients improved clinically. With an average follow-up of 31.2 months (range, 24-42 mo), the average modified Japanese Orthopaedic Association score was 7.8 (range, 6-10), representing a 2- to 5-point improvement. The average improvement rate was 55.2% (range, 33.3%-83.3%). Most patients were functionally independent at the last follow-up. Forty ossified segments were resected. The average time required for the resection of 1 segment was 77 minutes. Intraoperatively, dural ossification was noted in 11 patients. Complete resection was performed in all patients. Cerebrospinal fluid leakage occurred in 5 patients.

CONCLUSION

Segmental en bloc resection of the posterior wall of the thoracic canal is a safe and effective alternative for OLF-related severe thoracic myelopathy.

Clinical characteristics and surgical outcome of thoracic myelopathy caused by ossification of the ligamentum flavum: a retrospective analysis of 85 cases

STUDY DESIGN

A retrospective comparative study.

OBJECTIVES

To describe the clinical features and radiological findings, to assess the safety and effectiveness of posterior decompressive laminectomy and resection of the ossification of the ligamentum flavum (OLF), and to determine which presurgical and surgical variables were most closely related to postsurgical prognosis of thoracic myelopathy (TM) caused by OLF in China.

METHODS

Eighty-five patients with the diagnosis of TM caused by OLF received surgical treatment from July 1998 to May 2012. Clinical data were collected from medical and operative records. Correlations between the surgical outcome and various factors were also analyzed.

RESULTS

All cases were followed up for a mean of 49.2 months (range, 24-190 months) postoperatively. The mean Japanese Orthopaedic Association score was 3.8 points preoperatively and 8.2 points at the final follow-up, yielding a mean recovery rate of 63.0%. Postoperative complications included transient neurological deficits (9 cases), persistent neurological deficits (4 cases), dural tears (17 cases), cerebrospinal fluid leakage (9 cases), wound dehiscence (2 cases) and wound infection (3 cases). The OLF level (middle thoracic), preoperative duration of symptoms, intramedullary signal change on T2WI and preoperative severity of myelopathy were important predictors of surgical outcome.

CONCLUSIONS

Biomechanical and anatomical factors may have a key role in thoracic OLF progression. Posterior decompressive laminectomy and resection of the OLF can be considered an effective, reliable and safe alternative procedure. The OLF level, preoperative duration of symptoms, intramedullary signal change on T2WI and preoperative severity of myelopathy were confirmed and significantly correlated with the surgical outcome.

Ossification of the ligamentum flavum

Ossification of the ligamentum flavum is a rare cause of thoracic myelopathy. It develops in East Asians more frequently than in people from other areas. The exact pathophysiology has not been elucidated yet; however, it largely depends on biomechanical alterations, especially changes in the tensile force. Because the spinal cord is compressed from the posterior side, the first and most common clinical manifestation is usually loss of functional gait and spastic paralysis, which develop as the spinal cord compression progresses. The choice of diagnostic imaging is T2 sagittal magnetic resonance imaging scanning. Whole spine scanning is mandatory to identify multiple areas of compression and any associated distal lumbar diseases. Fine computed tomography imaging is necessary to make a differential diagnosis and set up a precise surgical plan. Conservative treatment does not work in this disorder. Decompression surgery is the only option and prognosis after surgical treatment is better with this disorder than with other causes of thoracic myelopathy. The severity of preoperative symptoms and the time interval before surgical treatment are the most important prognostic factors.

Treatment strategies for the surgical complications of thoracic spinal stenosis: a retrospective analysis of two hundred and eighty three cases

PURPOSE

Our aim was to investigate the causes of and treatment strategies for surgical complications of thoracic spinal stenosis.

METHODS

Between May 1990 and May 2010, 283 patients with thoracic spinal stenosis were treated in our department. Three physicians were assigned to patient follow-up. Patient medical records and radiographs were reviewed. Complications were categorised as perioperative, mid- to long-term and donor-site.

RESULTS

Follow-up was completed for 254 patients; 249 patients survived. Follow-up time ranged from one to 19 years, with a mean of six years and two months. There were 107 cases with complications an incidence rate of 42.1%. Eleven cases were pulmonary infection, seven transient nerve-root injury, three pulmonary injury and one vertebral canal haematoma, all of which resolved. Thirteen cases of spinal cord injury postoperatively were treated using dehydration and corticosteroid therapy; eight recovered to the preoperation level, and five deteriorated. Eleven cases resulted in dural injury, and four led to cerebrospinal fluid leakage. There were five cases of wound-fat liquefaction and one of wound infection. Seven cases with deep venous thrombosis of the lower limb resolved by elevating the affected limb and administration of low-molecular-weight dextran. Seven cases of delayed wound healing recovered following change of dressings and antibiotic administration. Four cases of delayed bone-graft fusion recovered by extending the external fixation time. One case of bone-graft absorption was treated by iliac bone grafting and bracing. Two cases of internal fixation breakage were treated by removing the internal fixation.

CONCLUSIONS

Thoracic spinal stenosis surgery may result in various complications but has a good prognosis with proper treatment. The key points in reducing complications are the surgeon's familiarity with operative imperatives and the appropriate surgical approach.

Variables affecting postsurgical prognosis of thoracic myelopathy caused by ossification of the ligamentum flavum

BACKGROUND CONTEXT

Ossification of the ligamentum flavum (OLF) may result in thoracic myelopathy (TM) because of narrowing of the spinal canal. Because symptoms vary and are subjective, diagnosis of TM caused by OLF is sometimes difficult when based on symptoms and physical examination. Posterior decompression is indicated in patients with TM caused by OLF because it is believed that surgery is the most effective treatment. However, surgical outcomes vary. We are unaware of reports of objective presurgical diagnostic parameters, such as neurologic and radiologic findings, relating to the postsurgical prognosis in patients with TM caused by OLF.

PURPOSE

To determine which presurgical and surgical variables were most closely related to postsurgical prognosis of TM caused by OLF.

STUDY DESIGN

Retrospective review of the records of the cohort of patients who had undergone surgery from 1988 through 2008 at the University of Toyama Hospital for TM caused by OLF.

PATIENT SAMPLE

Forty-one patients who had surgery for TM caused by OLF that was progressive, severe, or both and for which the diagnosis was based on clinical, radiologic, and pathologic evaluations.

OUTCOME MEASURES

Relationship between the highest follow-up Japanese Orthopaedic Association (JOA) score for neurologic evaluation and of Hirabayashi's formula to indicate the extent of normalization after surgery with respect to the following 10 variables: age at surgery; sex; duration of presurgical symptoms; complications of diabetes mellitus; complications of hypertension; presence of presurgical hyperreflexia in either or both of the patellar tendon reflex and the Achilles tendon reflex; presurgical impairment of joint position sense in the big toes; number of levels affected by OLF; concurrent spinal lesions including ossification of the posterior longitudinal ligament; and intramedullary change of the spinal cord seen on magnetic resonance imaging (MRI).

METHODS

Multiple linear analyses were used to evaluate the variables related to postsurgical recovery.

RESULTS

Presurgical impairment of joint position sense in the big toe was the most important predictor of the highest postsurgical JOA score and of the highest percentage recovery rate. The number of affected OLF levels also predicted the postsurgical highest JOA score, but not statistically significantly so. Age at surgery, sex, and duration of symptoms presurgically did not affect postsurgical recovery. Complications of diabetes mellitus or of hypertension did not affect percentage recovery rate. The difference between recovery rate in patients with or without concurrent spinal lesions was not significant. Presurgical hyperreflexia was not correlated with recovery. Postsurgical JOA scores and percentage recovery rates of scores in patients whose presurgical MRIs had shown intramedullary signal change were not statistically significantly different from those whose MRIs had not shown signal change.

CONCLUSIONS

An excellent postoperative prognosis is not always possible in patients with TM caused by OLF. It may be important to check for impairment of joint position sense in the big toe, the number of levels affected by OLF, and presurgical intramedullary signal change on MRI before continuing to surgery.

The frequency and treatment of dural tears and cerebrospinal fluid leakage in 266 patients with thoracic myelopathy caused by ossification of the ligamentum flavum

STUDY DESIGN

Retrospective review.

OBJECTIVE

To perform a single-institution analysis of incidence, treatment, and clinical outcome in patients with thoracic ossification of the ligamentum flavum (OLF) who experienced dural tears and cerebrospinal fluid (CSF) leakage.

SUMMARY OF BACKGROUND DATA

There is a paucity of clinical reports focusing on dural tears and CSF leakage after thoracic OLF surgery. Because dural adhesion and dural ossification are common features of thoracic OLF, the incidence of CSF leakage in OLF patients is high and represents a significant clinical challenge.

METHODS

A total of 266 patients with thoracic OLF were admitted to our hospital from 1995 to 2011. Each patient's medical records were reviewed to identify cases of dural tears and CSF leakage. Information on therapeutic strategy used to repair the dural tears and complications related to CSF leakage was extracted.

RESULTS

The incidence of dural tears and CSF leakage in OLF patients was 32% (85/266). The incidence of dural ossification was 25.2%. The dural tears were repaired with a range of materials, including gelatin sponge, muscle/fascia, artificial dura, silk suture, and fibrin glue. The intraoperative repair procedure did not resolve CSF leakage in 65 cases, and 16 of those cases experienced complications related to the continued CSF leakage, including CSF pseudocyst, wound dehiscence, and meningitis. Fifty-eight patients with CSF leakage were eventually cured by a series of comprehensive treatments, which included prone position, continuous pressure by sandbag, ultrasound-guided puncture, and aspiration. Only 7 patients required reoperation.

CONCLUSION

Dural ossification was the main reason for dural tears. In all, 78 of the 85 patients with CSF leakage or dural tear were successfully cured. The success rate was 91.8%, which indicated that a series of comprehensive treatments was an effective strategy to treat these patients.

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: a unique report of a Hispanic woman

Ossification of the ligamentum flavum (OLF) is a disease of ectopic bone formation within the ligamentum flavum, which may result in mass effect and neurological compromise. The low thoracic region is the most common region of occurrence, and this is followed by the cervical, then lumbar, spine. The prevalence of OLF is significantly higher in the Japanese population compared with other nationalities and has a male preponderance. Ossification of the ligamentum flavum has been reported in association with the more common ligamentous pathological entities—ossification of the posterior longitudinal ligament and diffuse idiopathic skeletal hyperostosis. These latter two conditions have been linked to several metabolic processes, and a possible genetic basis has been hypothesized. Here, the authors present a unique case of OLF of the cervical spine in a patient with idiopathic hypercalcemia.

Dural ossification in ossification of the ligamentum flavum: a preliminary report

STUDY DESIGN

A retrospective review.

OBJECTIVE

The aim of this study is to highlight one of the under recognized and under reported aspects of ossification of the ligamentum flavum (OLF), namely, dural ossification in OLF and to discuss the incidence, radiologic signs, causes as well as the surgical and prognostic implications of dural ossification in OLF.

SUMMARY OF BACKGROUND DATA

OLF is being increasingly recognized as a cause of myelopathy. One of the surgical pitfalls in the management of this condition is ossification of the dura mater in OLF. Preoperative identification of ossified dura mater will be helpful to the surgeon to modify the surgical technique and to counsel patients regarding the risks of surgery.

METHODS

A retrospective analysis of a database of OLF maintained by this author was done to identify cases of OLF where there was intraoperative evidence of dural ossification and dural laceration. Only those patients who had both computed tomography (CT) and magnetic resonance imaging (MRI) were included in the analysis. Patients with MR imaging alone were excluded from the analysis as CT evaluation was not done routinely in the earlier part of the study. Nurick's grading was used to assess the neurologic status before and after surgery. The CT and MR images of these patients were analyzed to identify radiologic signs of dural ossification. The pattern of dural ossification, if present, was noted. The intraoperative and postoperative complications were recorded.

RESULTS

During the study period from 1997 to 2006, there were 20 patients with OLF who had both CT and MR imaging evaluation. Of these 20 patients, 8 had intraoperative evidence of dural ossification and these patients also sustained dural laceration during surgery. Of these 8 patients, CT evidence of dural ossification was found in 7. In the remaining one patient, there was no radiologic evidence of dural ossification. The radiologic signs of dural ossification as depicted in the bone windows of CT were of 2 types: (1) the "tram track sign," where there was a hyperdense bony excrescence with a hypodense center and (2) the "comma sign," where there was evidence of ossification of one-half of the circumference of the duramater. Of these 7 patients, 4 developed cerebrospinal fluid (CSF) leak following surgery and 1 of these 4 patients developed meningitis. Neurologic function improved by one Nurick's grade in 5 of the 7 patients. In the remaining 2 patients, there was no change in the neurologic status.

CONCLUSION

Dural ossification is a common finding in OLF. There are 2 radiologic signs of dural ossification, namely, the "tram track sign" and the "comma sign." Preoperative identification of dural ossification might help the surgeon to anticipate and appropriately deal with dural laceration during surgery. This will also help to counsel patients regarding the risks of surgery for OLF. The surgical and prognostic implications of dural ossification are being discussed.

Removal of ossified ligamentum flavum via a minimally invasive surgical approach

Ossified ligamentum flavum (OLF) in the thoracic spine is a rare cause of myelopathy, often presenting with progressive symptomatology over an extended period of time. Surgical decompression via wide laminectomy has been the mainstay of treatment for this symptomatic disease phenomenon, but complications such as kyphotic deformity have developed due to extensive bone removal and release of the posterior tension band. The authors present a case of OLF excised via a minimally invasive microsurgical approach in which an expandable tubular retractor system was used. This approach enables complete decompression of the spinal canal while minimizing nerve, vascular, and musculoskeletal disruption, thus maintaining the native biomechanical disposition of the intact vertebral column.

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 at the lumbar spine: a retrospective study

STUDY DESIGN

A retrospective study on 9 patients treated for ossification of the ligamentum flavum (OLF) at the lumbar spine.

OBJECTIVE

To evaluate the clinical and radiologic findings as well as the postoperative results of the patients.

SUMMARY OF BACKGROUND DATA

Ossification of ligamentum flavum (OLF) in the lumbar region causing neurologic impairment is a rare pathologic entity described mainly in Japanese literature. The present study represents the largest surgical series of European patients with OLF at the lumbar spine.

METHODS

A retrospective study of 9 consecutive patients was conducted between 2000 and 2005. The clinical status was evaluated according to the Japanese Orthopedic Association scale. Potential associated disorders were also recorded. Diagnosis in each case was established using computed tomography and magnetic resonance imaging. Whole-spine magnetic resonance imaging was routinely used in order to reveal possible coexisting spinal lesions. Pathologic confirmation was available in all cases.

RESULTS

Radicular pain was the most common presenting symptom. Myotomal weakness was found in most of the cases. A majority of our patients had lesions located at the L3-L5 levels. Thoracic OLF was recorded as a spinal coexisting ossified lesion. Surgery led to neurologic improvement with a statistically significant increase in the Japanese Orthopedic Association score (P = 0.007). The median recovery rate was 91.60% +/- 43.85%.

CONCLUSION

It is possible that OLF is underreported in the Greek population. Surgical treatment is important in order to improve functional outcomes.

Surgical outcome of thoracic myelopathy secondary to ossification of ligamentum flavum

OBJECTIVES

Thoracic myelopathy secondary to OLF is a rare disease described almost exclusively in Japanese patients. Few series of OLF in South Korean subjects has previously been published. This study is to describe the clinical and radiologic aspects, as well as surgical outcomes in a group of South Korean patients.

METHODS

A retrospective study of 8 consecutive patients, including 4 men and 4 women (mean age, 55.6 years), was conducted from 2002 to 2005. Diagnosis in each case was established using CT. Magnetic resonance imaging was also performed in every case. All patients treated surgically and pathologic studies were performed. A comparison between the preoperative neurological status and the status at follow-up was done using Japanese Orthopaedic Association (JOA) scoring system.

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 (T10-T11). Decompressive laminectomy with excision of the OLF resulted in significant improvement in motor weakness and gait in 5 (2 excellent, 3 good) patients who had short duration and no hyperintense intramedullary lesion of spinal cord on MRI. All patients improved in their gait and spasticity, but 2 patients had persistent sensory deficit.

CONCLUSION

OLF is a rare cause of thoracic myelopathy. The frequency appears to have been rarely reported in South Korean subjects. CT with sagittal reconstructions and MRI are helpful for diagnosis and spinal cord involvement. When neurologic symptoms develop, decompressive laminectomy should be done immediately and the surgical outcome is generally good if hyperintense intramedullary signal changes of spinal cord have not yet developed.

Ossification of the ligamentum flavum: diet and genetics

Ossified ligamentum flavum (OLF) is being appreciated as an important cause of thoracic myeloradiculopathy. However, despite numerous epidemiological and basic science studies, the pathogenesis of OLF has not been conclusively established. Ossification and symptom development are significantly more frequent in the Japanese population, therefore supporting a genetic predilection for the disease process. We present an unusual case of OLF in a patient from a low-risk genetic background (Chinese), exposed in youth to a lifestyle and diet from a high-risk population (Japanese). Based on our case report, we support the view that dietary habits may constitute an independent risk factor for OLF and ossification of the posterior longitudinal ligament.

Medical Screening for Red Flags in the Diagnosis and Management of Musculoskeletal Spine Pain

When a patient presents with pain in the different regions of the spine, the clinician executes a region-appropriate basic examination that includes appropriate historical cues and specific physical examination tests that can be used to identify red flags. The clinical tests include a specific examination of the sensory and motor systems. Test outcomes are best interpreted in context with the entire examination profile, where the sensitivity and specificity of these tests can influence their utility in uncovering red flags. These red flags can be categorized based on the nature and severity or the specific elements of the patient's presentation. Many general red flags can be observed in any region of the spine, while specific red flags must be categorized and discussed for each spinal region. This categorization can guide the clinician in the direction of management, whether that management is aimed at redirecting the patient's care to another specialist, reconsidering the presentation and observing for clusters of findings that may suggest red flags, or managing the patient within the clinician's specialty in context with the severity of the patient's presentation.

Pathophysiology of cervical myelopathy

BACKGROUND CONTENT

Cervical myelopathy is a group of closely related disorders usually caused by spondylosis or by ossification of the posterior longitudinal ligament and is characterized by compression of the cervical spinal cord or nerve roots by varying degrees and number of levels. The decrease in diameter of the vertebral canal secondary to disc degeneration and osteophytic spurs compresses the spinal cord and nerve roots at one or several levels, producing direct damage and often secondary ischemic changes.

PURPOSE

Clinicians who treat cervical myelopathy cord injuries should have a basic understanding of the pathophysiology and the processes that are initiated after the spinal cord has been injured.

STUDY DESIGN/SETTING

Literature review.

METHODS

Literature review of human cervical myelopathy and clinically relevant animal models to further our understanding of the pathological mechanisms involved.

RESULTS

The pathophysiology of cervical myelopathy involves static factors, which result in acquired or developmental stenosis of the cervical canal and dynamic factors, which involve repetitive injury to the cervical cord. These mechanical factors in turn result in direct injury to neurons and glia as well as a secondary cascade of events including ischemia, excitotoxicity, and apoptosis; a pathobiology similar to that occurring in traumatic spinal cord injury.

CONCLUSIONS

This review summarizes some of the significant pathophysiological processes involved in cervical myelopathy.

Unusual CT/MR features of putative ligamentum flavum ossification in a North African woman

To display the unusual spinal CT and MR findings in a 48-year-old North African woman presenting with two adjacent intracanalar mineralized epidural outgrowths exhibiting mature bone organization with "cortical" and "trabecular" areas and pseudoarthritic changes at their interface. An unusual form of ligamentum flavum ossification (LFO) was speculated, of which features are discussed under the light of the available literature.

Ossification of the proximal thoracic ligamenta flava causing acute myelopathy in a Caucasian: case report and literature review

STUDY DESIGN

Case report and literature review.

OBJECTIVE

To illustrate that ossification of the proximal thoracic ligamenta flava can be a rare cause of acute myelopathy in a Caucasian patient and that timely surgery can lead to a good outcome.

SETTING

Nottingham, UK.

METHODS

Proximal multiple contiguous ossified thoracic ligamenta flava from T3/T4 to T5/T6 causing acute myelopathy was diagnosed in a Caucasian man based on history and examination followed by magnetic resonance imaging and computed tomography scanning. The literature is reviewed for all reported cases of ossified ligamenta flava causing myelopathy in Caucasians.

RESULTS

Following prompt diagnosis and T3 to T5 laminectomies, our patient made near-complete neurological recovery over a 10-month period. This condition usually affects the lower thoracic spine. Although chronic and subacute myelopathy secondary to this circumstance has been reported in Caucasians, acute myelopathy has not been reported and proximal thoracic involvement has been reported twice.

CONCLUSION

Ossification of the proximal thoracic ligamenta flava can be a rare cause of acute myelopathy in Caucasians. Prognosis following decompressive surgery is usually good.

Surgical treatment of 40 patients with thoracic ossification of the ligamentum flavum

OBJECT

The authors evaluated different surgical methods used to treat thoracic ossification of the ligamentum flavum (OLF).

METHODS

Data obtained in 40 patients who underwent posterior decompression for thoracic myelopathy caused by thoracic OLF were studied retrospectively. There were 32 men and eight women. All patients underwent posterior decompression in which laminoplasty was performed or laminectomy combined with lateral fusion. Every surgical specimen was stained with H & E, and scanning electron microscopy was performed in 20 cases. The mean follow-up period was 28 months. Postoperative outcomes were evaluated using a recovery scale based on the Japanese Orthopaedic Association classification. There were a total of 168 ossified segments in this series, 77.4% of which were located in the lower thoracic spine. Marginal osteophyte formation was found in 36 patients; in 32 of the 36 patients, these marginal osteophytes were located at the intervertebral space either higher or lower than the ossified segment. Scanning electron microscopy showed elastic fiber breakdown, proliferation of collagenous fibers, calcification, and OLF in the same microscopy region. Laminoplasty was performed in four patients. In three cases surgery resulted in unchanged or worse outcome (increased kyphotic deformity in two), and in one it resulted in good outcome. Laminectomy combined with lateral fusion was performed in 36 patients, in 30 cases of which it resulted in a good or fair outcome, and increased kyphotic deformity in only one. Of these 36 laminectomy-treated patients, an en bloc laminectomy-treated procedure was performed in 16 patients; in 11 of the 12 patients with lateral or diffuse-type lesions the surgery resulted in a good or fair outcome. En bloc laminectomy, however, seems ineffective in the treatment of patients with thickened, nodular-type thoracic OLF, as the procedure resulted in worse outcome in two of the four patients. The authors have thus developed a new modality of laminectomy that they have termed "separating laminectomy," which they performed in 16 patients with thickened, nodular-type OLF; in 13 cases it resulted in a good or fair outcome, and in only one case did it result in a worse outcome.

CONCLUSIONS

The pathogenesis of thoracic OLF is mainly due to the localized mechanical stress on the ligament. Laminectomy combined with lateral fusion is the treatment of choice for thoracic OLF; furthermore, in terms of the configuration of the ossified lesion, en bloc laminectomy is suitable for the treatment of lateral-type and diffuse-type OLF, and the separating laminectomy is suitable for the thickened, nodular-type OLF.

Spinal compression due to ossified yellow ligament: a short series of 5 patients and literature review

BACKGROUND

Ossification of ligamentum flavum in the thoracic region causing compressive myelopathy among middle-aged patients is a poorly described entity.

CASE DESCRIPTION

Five patients of Indian origin with OYL are described. Their clinical presentations, surgical options, and long-term outcome are presented. Radiologic and clinical follow-up of one of the patient is described over a span of 10 years.

CONCLUSIONS

Decompressive laminectomy and excision of the OYL is the commonly performed surgical procedure. A rapid neurologic improvement follows decompression. The persistent spasticity in certain patients is attributed to irreversible changes within the cord. The disease is thought to be progressive in nature. The prolonged follow-up of these patients suggests that the long-term prognosis is poor. Selective racial involvement and variable clinical presentations, with treatment options, are discussed.

Clinical and prognostic analysis of ossified ligamentum flavum in a Chinese population

OBJECT

The authors performed a retrospective study of clinical and radiological data obtained in 27 Chinese patients with myelopathy induced by ossification of the ligamentum flavum (OLF) who underwent surgery between March 1990 and March 2002. The factors related to surgical outcome of thoracic OLF-induced myelopathy were also assessed.

METHODS

The preoperative clinical features and radiological findings were reviewed retrospectively. Preoperative and postoperative neurological status was assessed using the Japanese Orthopaedic Association (JOA) scoring system and the Nurick Scale. The ossified lesions were classified into five types (lateral, extended, enlarged, fused, and tuberous). Multiple linear regression and logistic regression analyses were performed to establish the factors affecting surgical outcome. The patients' chief complaints were lower-limb weakness and gait disturbance (93%), numbness and sensory deficit (89%), and low-back pain (48%). The coexisting pathological entities were disc herniation, canal stenosis, and ossification of posterior longitudinal ligament. The ossified ligamentum flavum was mainly located at the T10-12 (67%) and T1-3 (15%) levels. Symptoms in 26 patients improved but resolved completely in only 14 after surgery. The mean overall JOA score was 5.3 +/- 1.9 preoperatively and 7.9 +/- 2.3 postoperatively. There is a significant difference between the pre- and postoperative neurological status (p < 0.05) determined by the Student t-test. The recovery rate was 46.3 +/- 9.4%. Multiple regression analysis revealed negative correlation between the duration of preoperative symptoms and surgical outcome as well as a positive correlation between the preoperative JOA score and surgical outcome. Logistic regression analysis demonstrated that fecal and/or urinary incontinence, positive patellar and/or ankle clonus, and intramedullary high T2-weighted magnetic resonance (MR) imaging signal change had negative effects on the surgical outcome.

CONCLUSIONS

The clinical and radiological features of OLF in the Chinese population are similar to those observed in the Japanese population. The duration of preoperative symptoms and JOA score are the most important predictors of the postoperative JOA score and recovery rate. The patients with fecal and/or urinary incontinence, positive patellar and/or ankle clonus, and intramedullary high T2-weighted MR imaging signal change were at higher risk of poor outcome after surgery.

Acute quadriparesis caused by calcification of the entire cervical ligamentum flavum in a white female--report of an unusual case and a brief review of the literature: case report

STUDY DESIGN

Case report.

OBJECTIVES

To describe an extremely unusual case of acute quadriparesis in a white female caused by calcification of the ligamentum flavum (LF) from C1 to T2, and to review briefly the pertinent literature.

SUMMARY OF BACKGROUND DATA

Diseases characterized by abnormal calcium deposition on the spinal ligaments have an unclear etiology. The overwhelming majority of these cases has been reported in people of Asian descent and has a predilection for the thoracic spine. Multilevel involvement of the cervical LF in white patients is exceptionally rare. To our knowledge, complete calcification of the entire cervical LF has not been previously reported in the literature.

METHODS

The history, physical examination, and radiographic studies of a 64-year-old white female with a history of scleroderma are described. The patient presented with neck pain and acute quadriparesis caused by spinal cord impingement by calcified cervical LF from C1 to T2. The patient underwent emergent C3-C7 laminectomy and C2-C7 posterior spinal fusion.

RESULTS

Operative intervention resulted in marked neurologic improvement and relief from neck pain. Histopathologic examination of the calcified LF showed that the deposits consisted of hydroxyapatite crystals exclusively with no heterotopic bone. However, kyphosis did develop in the patient after laminectomy.

CONCLUSION

To our knowledge, this unusual case of complete calcification of the entire cervical LF has not previously been described. Multilevel laminectomy and fusion can improve neurologic function but may result in kyphosis.

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.

Factors related to long-term outcome after decompressive surgery for ossification of the ligamentum flavum of the thoracic spine

OBJECT

Factors related to long-term surgical outcome of thoracic myelopathy caused by ossification of the ligamentum flavum (OLF) have not been fully investigated. To evaluate these factors, the authors reviewed medical records obtained in patients who had undergone decompressive surgery for thoracic OLF.

METHODS

Thirty-four patients in whom decompressive surgery was performed for thoracic OLF (mean follow-up period 8 years) were recruited. Fourteen patients underwent simultaneous decompressive surgery for cervical or lumbar lesions. Patient age, duration of symptoms, OLF type, dural adhesion, neurological status classified by the Japanese Orthopaedic Association (JOA) scale before and after surgery (1 month postoperatively and at final follow up), and recovery rate were reviewed. The ossified ligamentum flavum was classified into five types according to Sato's classification by assessing preoperative computerized tomography scans. The mean preoperative JOA score (5) was significantly improved at 1 month after surgery (7.1) and at final follow up (7.9) (p < 0.05). Recovery rates at 1 month and at final follow up were 34.6 and 44.2%, respectively. No significant correlations were found between age, OLF type, and neurological status before and after surgery. In patients with dural adhesion, which was observed in cases of larger-type OLF (p < 0.02), lower JOA scores were observed compared with those in patients without dural adhesion both preoperatively and at 1 month after surgery (p < 0.05) but not at the final follow-up examination. Higher JOA scores and recovery rates were demonstrated in patients who had undergone simultaneous surgery than in those who had not undergone simultaneous surgery at 1 month (p < 0.05) but not at the final follow up. Using multiple regression analysis, the authors identified the duration of preoperative symptoms as the most important predictor of a high JOA score and recovery rate at the final follow up.

CONCLUSIONS

Duration of preoperative symptoms represents the most important predictor of long-term surgery-related outcome in patients treated for thoracic OLF. The type of ossified ligamentum flavum, dural adhesion, and simultaneous surgery for coexistent cervical or lumbar lesions do not appear to influence the long-term postoperative prognosis.

Radiculopathy due to ossification of the yellow ligament at the lower lumbar spine

STUDY DESIGN

A case report.

OBJECTIVES

To report a rare case of a 27-year-old female with ossification of yellow ligament at the lower lumbar spine presenting radiculopathy with a drop foot.

SUMMARY OF BACKGROUND DATA

The majority of cases of ossification of yellow ligament occur at the lower third of the thoracic or the thoracolumbar spine. There are only a few reports of ossification of yellow ligament in the lumbar spine and radiculopathy due to ossification of yellow ligament at L4-L5 and L5-S1 levels is very uncommon.

METHODS

A 27-year-old female with a prior fracture of posterior ring apophysis of L5 presented with leg pain and a drop foot. Magnetic resonance imaging demonstrated stenosis with compression of the cauda equina at the L4-L5 and L5-S1 levels.

RESULTS

Decompressive laminectomy of L5 and removal of the ossified yellow ligaments were performed. Histologic examination of en bloc specimen of ossification of yellow ligament revealed degenerative changes of the elastic fibers in the yellow ligament with adjacent chondrosis and ossification. The patient's severe leg pain disappeared completely, although the extent of the drop foot had not fully recovered at the final follow-up examination.

CONCLUSIONS

The mechanism of ossification of yellow ligament in the present case was unclear. The patient did not have any previous generalized disorders besides the history of a ring apophysial fracture or any family history of treatment for ossification of the posterior longitudinal ligament or ossification of yellow ligament. Therefore, localized mechanical stress might have influenced the development of ossification of yellow ligament at lower lumbar spine.

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.

Paraparesis in a black man brought on by ossification of the ligamentum flavum: case report and review of the literature

We present the second case of paraparesis secondary to ossification of the ligamentum flavum at the midthoracic region in a black man. Ossification of the ligamentum flavum is frequently described in the Japanese population where the presentation is often in the lower thoracic region. The patient is a 37-year-old black man who, over the 6 months before admission, noticed progressive paraparesis. CT myelogram revealed severe thoracic stenosis by an ossified ligamentum flavum from T4 to T7 with most severe involvement at the T5, T6, and T7 levels. The patient underwent multilevel laminectomies and medial facetectomies from T4 to T7. Over the past decade, ossification of the ligamentum flavum has been reported with increasing frequency in non-Asian patients. This is the third case report in a black man. In addition, ossification of the ligamentum flavum in this particular location is rarely reported. The increased use of advanced neuroimaging techniques in the evaluation of "back pain" may reveal that the prevalence of this condition is higher than expected in non-Asian populations. Improvement in neurologic symptoms secondary to decompressive laminectomies will depend on the degree and duration of spinal cord compression.

Thoracic vertebral osteophyte-causing myelopathy: early diagnosis and treatment

STUDY DESIGN

A case report is described.

OBJECTIVE

To highlight an unusual cause of thoracic myelopathy.

METHODS

Clinical evaluation of 63-year-old male revealed myelopathy. Thoracic cord compression from a solitary projection of a facetal joint osteophyte at the T9-T10 level was documented on magnetic resonance imaging scans and computed tomography scans.

RESULTS

The osteophyte was successfully excised.

CONCLUSIONS

Thoracic cord compression can be caused by various space-occupying lesions, and a high index of suspicion will lead to diagnosis before neurologic deficit is clinically expressed. Magnetic resonance imaging scans and computed tomography scans both demonstrate the osteophyte, and expedient surgery avoids the progression of the neurologic deficit.

Myelopathy caused by ossification of ligamentum flavum

STUDY DESIGN

Retrospective study of seven cases of ossification of ligamentum flavum from two urban hospitals in a Chinese population.

OBJECTIVES

To inspect the epidemiology, clinical presentation, pathology, and treatment outcome in these Chinese patients with ossification of ligamentum flavum.

SUMMARY OF BACKGROUND DATA

Ossification of ligamentum flavum involving the lower thoracic region is relatively common in the Japanese population. It is usually presented with myelopathy of progressive nature.

MATERIALS AND METHODS

Five patients were male and two were female. The mean age was 52 years (range 41-73 years). Diagnosis was made by CT scan, MRI, and subsequent histology. Six patients have been treated by laminectomy and one by laminoplasty. The average follow-up duration is 34 months (range 26-44 months). The outcome is evaluated by Japanese Orthopaedics Association (JOA) score.

RESULTS

The average time of presentation from the onset of symptoms was 9 months (range 3-12 months). Most of the patients presented with lower limb numbness and gait disturbance. One case was presented after a minor trauma. Mean JOA score was 4.8 (range 2-7, of 11). The lower thoracic level was the most frequently involved region. One case was associated with ossification of the posterior longitudinal ligament. Two patients had transient postoperative neurologic deterioration, which improved subsequently. Mean percentage of recovery after surgery in terms of JOA score is 65% (25-100%), with a mean final JOA score of 7.8.

CONCLUSION

Ossification of ligamentum flavum is an uncommon cause of myelopathy in the Chinese population. It can present acutely after minor trauma. Posterior decompression, especially with en bloc dissection of laminae, gives satisfactory results.

Thoracic spinal cord compression by ligamentum flavum ossifications

Ossification of the ligamentum flavum is common in Japan but rare in Western countries. Myelopathy of variable severity is a possible complication. Extension of the lesions over several levels at the thoracic spine is exceedingly rare. We report a new case in a 50-year-old man who had slowly progressive spinal cord compression with a sensory level at the navel. Computed tomography (CT) and magnetic resonance imaging (MRI) of the thoracic spine showed calcium-density masses that were in contact with the neural arches and bulged into the spinal canal at T5/T6, T7/T8, T9/T10, and T10/T11. Laboratory test findings were unremarkable. Surgical decompression by laminectomy and foraminotomy was followed by a favorable outcome. Histology showed extensive areas of bone metaplasia associated with calcific deposits. The diagnosis, treatment, and possible etiologies of this rare condition are discussed based on a literature review.

Disc Related and Non-Disc Related Disorders of the Thoracic Spine

Different anatomical structures and pathophysiological functions can be responsible for lumbar pain, each producing a distinctive clinical profile. Pain can arise from the intervertebral disc, either acutely as a primary disc related disorder, or as result of the degradation associated with chronic internal disc disruption. In either case, greatest pain provocation will be associated with movements and functions in the sagittal plane. Lumbar pain can also arise from afflictions within the zygapophyseal joint mechanism, as a result of synovitis or chondropathy. Either of these conditions will produce the greatest pain provocation during three-dimensional movements, due to maximal stress to either the synovium or joint cartilage. Finally, patients can experience different symptoms associated with irritation to the dural sleeve, dorsal root ganglion, or chemically irritated lumbar nerve root. Differential diagnosis of these conditions requires a thorough examination and provides information that can assist the clinician in selecting appropriate management strategies.

Cord compression secondary to cervical disc herniation associated with calcification of the ligamentum flavum: case report

OBJECTIVE AND IMPORTANCE

Calcification of the ligamentum flavum is a rare disease that occurs almost exclusively in elderly Japanese people. We report the case of a young Caucasian woman who presented with a C5-C6 disc herniation associated with a cervical calcified ligamentum flavum.

CLINICAL PRESENTATION

The patient presented with a cord compression syndrome of 76 hours' evolution. At exploration, a Brown-Sequard syndrome at the C6 level was found. Magnetic resonance imaging and computed tomography led to a correct diagnosis and planning for decompression.

INTERVENTION

We operated on the patient through a combined anterior and posterior approach. After the patient underwent anterior discectomy with intersomatic arthrodesis, we performed posterior decompression. During the operation, we observed that the dura mater could not be separated from the ligamentum, so an en bloc excision of both structures was performed. Microscopic examination indicated that the excised ligamentum had calcification, and total integration of the dura mater into the structure of the ligamentum was demonstrated. To our knowledge, this circumstance has never been described before. A posterior C3-C7 arthrodesis was performed to prevent postoperative kyphosis. Recovery was successful, with total recovery from neurological deficits 4 months later.

CONCLUSION

Calcification of the ligamentum flavum is a progressive disease that starts early in life and becomes symptomatic later in life when spinal stenosis occurs. Magnetic resonance imaging and computed tomography provide adequate diagnosis and allow proper surgical planning for decompression. The presence of hyperintense areas within the spinal cord parenchyma, in the absence of a traumatic antecedent, does not preclude a complete recovery.

Thoracic myelopathy due to enlarged ossified yellow ligaments. Case report and review of the literature

Enlarged ossified yellow ligaments are a rare and poorly understood cause of thoracic myelopathy. The authors report the case of a patient in whom thoracic myelopathy was caused by enlarged ossified yellow ligaments.