Ossification of the posterior longitudinal ligament of the cervical spine

Introduction

Introduction to ossification of the posterior longitudinal ligament of the cervical spine Cervical posterior longitudinal ligament ossification refers to the ossification of the posterior longitudinal ligament of the cervical vertebra, which oppresses the spinal cord and nerve roots, resulting in limb sensation and movement disorders and visceral autonomic dysfunction. The occurrence and development of ossification of the posterior longitudinal ligament of the cervical spine is generally slow, so patients may not have any clinical symptoms in the early stage, but when the ossification block is thickened to a certain extent, the cervical spinal canal stenosis is caused, or the lesion process is faster. In the case of trauma, or the ossification of the posterior longitudinal ligament is not serious, but with developmental spinal stenosis, it can cause compression of the spinal cord or spinal cord blood vessels, so patients often have symptoms after middle age. basic knowledge The proportion of illness: 0.003% Susceptible people: no specific population Mode of infection: non-infectious Complications: Dehydration Diffuse idiopathic bone hypertrophy

Cause

The cause of ossification of the posterior longitudinal ligament of the cervical spine

Disorders of glucose metabolism (18%):

There are reports in the literature that 15.6% of patients with ossification of the posterior longitudinal ligament of the cervical spine have diabetes. Japanese scholars report that 12.4% of patients with ossification of the posterior longitudinal ligament of the cervical spine have diabetes, and 28.4% of patients with abnormal glucose tolerance test. The incidence of ossification of the posterior longitudinal ligament is also higher than that of normal people.

Trauma factor (10%):

Some people have found in clinical observation that people who like to bend the spine are prone to ossification of the posterior longitudinal ligament, which indicates that the ossification of the posterior longitudinal ligament is related to the dynamic and static load of the spine. When the cervical vertebra activity is large, it is easy to cause the attachment of the posterior longitudinal ligament. Reactive ossification occurs during injury, especially when the cervical vertebra repeatedly performs flexion, and the posterior longitudinal ligament is repeatedly injured due to repeated traction of the posterior longitudinal ligament, and ossification occurs.

Other factors (5%):

Mainly due to the theory of calcium metabolism abnormalities and genetics, the former is found in patients with hypoparathyroidism and familial hypophosphatemic rickets, abnormal calcium metabolism and ossification of the posterior longitudinal ligament Therefore, it is presumed that the two are related. The latter is mainly due to the fact that in the second-degree relatives of patients with ossification of the posterior longitudinal ligament, the incidence of ossification of the posterior longitudinal ligament is as high as 30%, which is significantly higher than that of the general population.

Intervertebral disc degeneration factor

Japanese scholars Suzuki and Sishan believe that after the degeneration of the intervertebral disc, the stress in the posterior longitudinal ligament increases, and in the process of degeneration and repair of the surrounding tissue, local tissue hyperplasia is caused, and calcium deposits cause ossification. Some scholars such as Hamada and others believe that the posterior longitudinal ligament ossification of the intervertebral disc is milder, while the intermittent ossification of the intervertebral disc degeneration is heavier. Therefore, he believes that the continuous posterior longitudinal ligament ossification system Due to factors, it is not related to intervertebral disc degeneration, and the ossification of the posterior longitudinal ligament is caused by degeneration of the intervertebral disc.

Systemic bone hypertrophy

Many scholars have found that in patients with ossification of the posterior longitudinal ligament of the cervical spine, about 23.9% of cases have vertebral idiopathic diffuse mastitis, 6.8% with ligamentum flavum, and 2% with ankylosing spondylitis. Therefore, it is speculated that it is associated with hypertrophic changes in the body and joints.

Prevention

Prevention of ossification of the posterior longitudinal ligament of the cervical spine

The cause of the disease is still unclear, so there are no effective preventive measures. Stay optimistic and happy. Long-term mental stress, anxiety, irritability, pessimism and other emotions will make the balance of the cerebral cortex excitatory and inhibition process imbalance, so you need to maintain a happy mood.

Complication

Complications of ossification of the posterior longitudinal ligament of the cervical spine Complications, dehydration, diffuse idiopathic bone hypertrophy

1. Cervical degenerative changes:

The degenerative changes of the cervical spine are aggravated with the increase of age. The pathological changes involve the intervertebral disc, vertebral body, lamina, facet joints, ligaments and other parts, such as dehydration and degeneration of the intervertebral disc, protrusion, stenosis of the intervertebral space, and hyperosteogeny of the posterior margin of the vertebral body. , small joint hyperplasia, lamina thickening, ligament hypertrophy, etc., there is a close relationship between cervical degenerative changes and ossification of the posterior longitudinal ligament. On the one hand, although the etiology of posterior longitudinal ligament ossification is not clear, the degenerative change is One of the factors that cause ossification of the posterior longitudinal ligament has been recognized. On the other hand, when the posterior longitudinal ligament is ossified and a certain activity is restricted in a certain segment of the cervical vertebra, the upper and lower intervertebral space and the small joint of the part are limited. The load activity will increase and it will gradually appear and accelerate the degenerative changes.

2. Diffuse idiopathic hyperostosis (DISH):

This disease, also known as Forestier disease, is a common disease in the elderly. The clinical symptoms of most patients are not obvious. The main pathological changes are several vertebral anterior and lateral calcifications and ossification of the spine, with or without nerve compression. Symptoms, calcification and bone hyperplasia usually occur in the attachment of peripheral bone and tendon and ligament. DISH is more common in the lower thoracic and lumbar segments. Typical X-ray films show anterior and posterior vertebral coherence, wide ossification zone, and intervertebral space in the affected area. Normally, a considerable number of OPLLs have been found to be associated with DISH, or DISH with OPLL. Some authors believe that OPLL is a special type of DISH, but after epidemiological investigation, it is found that there is a relationship between DISH and OPLL. Differences should not be considered as the same disease.

3. It can also be complicated by urinary incontinence and low bowel function. It can be intermittent, chronic, progressive, and paralyzed.

Symptom

Symptoms of ossification of the posterior longitudinal ligament of the cervical spine Common symptoms Neck can be flexed, afraid of the spinal cord compression sphincter dysfunction, sensory disturbance, limb numb constipation, weakness, quadriplegia, spinal cord disease

1. General overview

The occurrence and development of ossification of the posterior longitudinal ligament of the cervical spine is generally slow, so patients may not have any clinical symptoms in the early stage, but when the ossification block is thickened to a certain extent, the cervical spinal canal stenosis is caused, or the lesion process is faster. In the case of trauma, or the ossification of the posterior longitudinal ligament is not serious, but with developmental spinal stenosis, it can cause compression of the spinal cord or spinal cord blood vessels, so patients often have symptoms after middle age.

2. Neck symptoms

In the early stage of the disease, the patient's neck may be mildly painless and gradually mild pain and discomfort; the cervical vertebra activity is mostly normal or slightly restricted, and the head and neck extension is limited; when the passive activity exceeds its normal range of motion, it may cause Neck pain or soreness.

3. Neurological symptoms

Mainly the symptoms of spinal cord compression, which are characterized by varying degrees, and may have intermittent, chronic progressive, spastic quadriplegia. Generally, upper extremity symptoms gradually appear from the lower extremities. In a few cases, upper extremity symptoms or limbs may occur first. Onset.

(1) Upper extremity symptoms: mainly the weakening of muscle strength on one or both sides of the hand or arm, and numbness, weakness and flexibility of hand movements are reduced. In severe cases, pens cannot be taken, chopsticks or small items are pinched; Most of the patient's grip strength decreased, the muscles showed moderate or mild atrophy, especially large, small fish is obvious, painfulness can be found during the examination; the Hoffman sign is mostly positive.

(2) Lower extremity symptoms: mainly manifested as weakness of the lower limbs, difficulty in lifting, dragging the ground or trepidation of the gait, there is a feeling of stepping on the cotton, the adductor tendons are obvious, the path is scissor gait, and there are double The lower limbs are numb, weak and paralyzed. In severe cases, they can not sit up and turn over themselves. They are completely squatting on the bed. The muscle tension of the lower limbs is increased, the sputum reflexes are active or active, the sputum sputum is positive, the pathological reflex is mostly positive, and there may be deep feeling and shallow feeling. Decrease.

(3) Other symptoms: mainly urinary sphincter dysfunction, manifested as dysuria or urinary incontinence; defecation function is also low, every 3 to 5 days, often constipation and bloating, patients with chest and abdomen can have a sense of belt, and It is easy to detect the plane of pain disorder, abdominal wall reflex and cremaster reflex weakened or disappeared.

4. Classification of spinal cord involvement in ossification of the posterior longitudinal ligament

The degree of involvement of the spinal cord and spinal nerve roots varies, and may even be unchanged. Clinically, the following five types are generally classified according to the degree of involvement of nerve tissue.

(1) spinal cord transection type: refers to the level of spinal cord involvement below the level of movement and sensory function is a transverse disorder, which is a common and more serious type of ossification of the posterior longitudinal ligament, the symptoms include numbness of the limbs, movement disorders, delicate fingers Limited activity, difficulty walking, and loss of urination.

(2) Brown-Sequard sign: manifested as one side of motor paralysis and contralateral sensory disturbance, which is more common in the ossification of the posterior longitudinal ligament, but there are fewer typical cases encountered in the clinic, mostly Symptoms cross each other and gradually transition to the typical manifestations of increasingly symptomatic symptoms.

(3) Sock-like paralysis type: the fingers of the hands and feet, the abnormalities of the toes (numbness, foreign body sensation), and the movement disorders of the hands and feet, etc., are sleeve-shaped, because the outer part of the spinal cord is exposed from the outside to the inside. Caused by oppression, it is also a common type in clinical practice.

(4) central tube type of the spinal cord: patients with ossification of the posterior longitudinal ligament are more prone to paralysis than normal people when they are traumatized, including central tube injury of the spinal cord, which is characterized by severe paralysis of the hand, but the foot has almost no symptoms. Or only mild dyskinesias.

(5) nerve root type: Strictly speaking, this type of patient is rarely encountered clinically. If the patient has neck pain or pain on one side of the upper limb, it should be considered as nerve root damage.

Examine

Examination of ossification of the posterior longitudinal ligament of the cervical spine

1. Simple X-ray film and tomography: On the X-ray lateral slice of the cervical vertebra, there can be abnormal shadows behind the vertebral body. The large ossified shadow of the white stick is continuous ossification, and the large ossified shadow is Hybrid type, easy to diagnose, but small ossification shadows such as segmentation type, limited type, etc., X-ray plain film diagnosis will cause misdiagnosis, at this time often need to do cervical lateral tomography, on the fault film, A white stick-like protrusion thicker than the vertebral body was photographed and adhered to the posterior aspect of the vertebral body.

2. CT examination: CT examination of the cervical cross-sectional state is extremely useful for diagnosing this disease. Generally speaking, when scanning is performed in three layers within the scope of a vertebral body, the vertebra can be clearly displayed. The prominent bone in the tube (OPLL), the shape of the bone is different, there are wide-based, small and sharp, in addition, the degree of maturity of ossification can also be seen from the CT index, the choice of treatment In particular, the operation of surgical procedures is crucial.

3. MRI examination: In recent years, MRI examination has been widely used in the diagnosis of cervical and cervical spinal cord, especially for the diagnosis of disc disease and spinal cord lesions, but for this disease, its specificity is not too high, because ossification The shadow appears as a low signal on the MRI image, which is difficult to distinguish from the epidural tissue around it, the normal posterior longitudinal ligament, etc.; however, it can be seen that the spinal cord morphology is thinned due to the compression of the ossification site, in addition, MRI examination It is also important for the differential diagnosis of cervical spondylotic myelopathy, cervical disc herniation, and spinal cord tumor.

4. Other

(1) Myelography: It is often necessary to use myelography to determine the location of the operation. The angiography of the cerebellar medullary canal is used for the descending stenosis, and the stenosis and obstruction signs can be seen from the radiograph. Wait until the surgical site is determined; CT (CTM) can also be performed at the same time to understand the stenosis from the CT cross section of myelography.

(2) Intervertebral disc angiography: If the ossification of the posterior longitudinal ligament of the cervical spine is the main reason and can discriminate the disc disease, it is not necessary to do discography, but sometimes the disc herniation may be the main pathogenic factor and the MRI examination technique is lacking. , discography should be performed to understand the changes in the intervertebral disc and the presence or absence of induced pain during observation and examination.

(3) EMG examination: EMG examination also has significance for the diagnosis of the level and extent of neurological symptoms, and may be used as appropriate.

Diagnosis

Diagnosis and differentiation of ossification of posterior longitudinal ligament of cervical spine

Through imaging examination, it is not difficult to have a disease similar to the symptoms.

All diseases of the cervical vertebrae should be the target of this disease, such as cervical spondylotic myelopathy, cervical disc herniation, cervical spinal cord tumor and spinal cord degenerative diseases.

Cervical spondylotic myelopathy

The ossification of the posterior longitudinal ligament of the cervical spine must first be differentiated from cervical spondylotic myelopathy. The two symptoms are similar, and the age of onset is similar. It cannot be ignored. In the case of cervical spondylosis, more than two vertebrae are often seen on the X-ray film. The narrowing of the gap, especially at the level of the neck 4 ~ 5, the neck 5 ~ 6 and the neck 6 ~ 7 is more obvious, in addition, the sagittal diameter of the lower cervical spinal canal is often not less than 1.2cm, and, in the cervical vertebrae, When stretching, it is often seen that the posterior edge of the superior vertebral body has a tendency to slide forward and backward for the lower vertebral pedicle (trapezoidal change). Of course, it should also be noted whether the presence of OPLL is accompanied by spinal stenosis and When OPLL coexists with spinal cord lesions, it is almost impossible to distinguish between the two. From the clinical symptoms, cervical spondylosis progresses more slowly, the pain is lighter, and the patient's disease awareness is also mild.

2. Cervical disc herniation

This is a disease of the spinal cord and nerve roots caused by disc disease, usually caused by severe physical activity, rapid cervical flexion and sneezing, and some is caused by the rapid decline of the aircraft. The age of the hair is lighter than OPLL. Most of them are between 30 and 50 years old. Many patients can not fall asleep at night because of severe pain. If the nucleus pulposus is prominent on the MRI image, the diagnosis is very easy.

3. Cervical spinal cord tumor

Cervical spinal cord tumors can be found in all age groups, including those aged 50 to 60 years old, so it is also important to identify them. The cervical subdural extramedullary tumor is characterized by chronic progressive bilateral upper and lower extremity paralysis. It can also be accompanied by pain in the hands and trunk. The distance between the two sides of the vertebral arch is increased on the X-ray film. The vertebral arch itself also gives a fragile feeling. From the CT slice, the vertebral arch of the patient with cervical spinal cord tumor is thin. Chemotherapy is not uncommon. Contrast and MRI can clearly show the shape of the tumor. In patients over 60 years old, the spinal epidural tumor is mostly metastatic tumor, so it is accompanied by severe neck pain. Both the plain film and the CT film show bone destruction. In addition, while doing bone radionuclide scanning, it is necessary to ask other departments to find the primary tumor.

4. Spinal degenerative diseases

Spinal degeneration can also have some degree of cervical vertebra hyperplasia and partial ossification of the posterior longitudinal ligament, but it has the characteristics of bilateral lower limb muscle strength is significantly lower, such as the early stage of amyotrophic lateral sclerosis In addition, spinal degenerative disorders generally do not have sensory disturbances, even if the sensory disturbance is very mild; but muscle atrophy, muscle weakness and other symptoms are progressive, this time should be supplemented by EMG and muscle biopsy to determine the lesions. The part.

5. Identification with ossification of the cervical ligamentum flavum.

Was this article helpful?

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.