Cauda equina syndrome is a clinical symptom complex that occurs when a bundle of nerve trunks of the terminal spinal cord is affected. The main symptoms are weakness in the lower extremities, sensory disorders in the area of innervation of the affected nerves, pelvic dysfunction by the type of delay. It is diagnosed according to neurological examination, the etiology of the lesion is established using MRI, CT, lumbar puncture, analysis of cerebrospinal fluid. Treatment includes conservative and surgical methods, followed by comprehensive rehabilitation.
ICD 10
G83.4 Cauda equina syndrome
General information
The spinal cord ends at the level of the first lumbar vertebra, the spinal nerves of the underlying segments (lumbar, sacral, coccygeal) together with the terminal thread form a bundle called the ponytail. The lesion of this formation, regardless of the etiology, is manifested by a clinically homogeneous symptom complex, isolated by specialists in the field of vertebroneurology into a separate syndrome. Most often, cauda equina syndrome is observed in middle-aged patients. Pathology is rare in children, it occurs due to injuries and anomalies of the structure of the lower parts of the spinal canal. Men get sick more often than women, because lifting weights plays a significant role in the occurrence of the disease.
Causes
The leading mechanism of damage to the terminal nerve bundle is its compression in the spinal canal. The most common cause is an intervertebral hernia of the lumbar spine. Inflammatory and iatrogenic lesions are less common. The main etiofactors that can provoke cauda equina syndrome include:
- Intervertebral hernia. Causes 15% of cases of the disease. It is formed due to osteochondrosis, degenerative changes of the intervertebral disc, leading to its prolapse. When formed in the lumbar region, it causes compression of the ponytail.
- Traumatic injuries. Lumbar spinal cord injury, fracture of the sacrum, coccyx are often accompanied by direct injury to nerve fibers. Hemorrhages in the spinal canal, post-traumatic hematomas lead to their compression. Iatrogenic injury is possible – in rare cases, the syndrome is a complication of epidural anesthesia, surgical operations in this area.
- Neoplasms. Malignant tumors of the ponytail infiltrate nerve bundles, causing the destruction of nerve fibers. Benign neoplasias develop from nerve sheaths (neurinoma), ependyma of the spinal canal (ependymoma), adipose tissue (lipoma), meningioma, are a factor of compression of nerve roots.
- Deformities of the spine. Congenital anomalies of the spine in the lumbosacral region, causing narrowing of the terminal part of the spinal canal, create favorable conditions for compression of nerve bundles passing through it. Acquired deformities occur due to age-related changes (deforming spondyloarthrosis), displacement of the lumbar vertebrae (spondylosis).
Pathogenesis
The lumbar and sacral spinal nerves forming the ponytail innervate the lower extremities, external genitalia, bladder, urethra, and the terminal parts of the rectum. Their defeat at the initial stages causes irritation and hyperexcitability of nerve fibers, which is clinically manifested by pain syndrome. As the nerve trunks are destroyed or compressed, their function fades, leading to a decrease or loss of sensitivity, paresis of the muscles of the innervated zone. Malignant neoplasia can destroy the membranes, the walls of the spinal canal, give metastases, which are accompanied by symptoms of damage to the corresponding organ.
Symptoms
The first manifestation is a pain syndrome. The pains are localized in the lumbar and sacral region, radiate to the lower limb on the side of the lesion, the inguinal zone. Patients complain of hypersensitivity (hyperpathy), unpleasant sensations (paresthesia), which coincide with pain in localization. The pain syndrome increases with coughing, sneezing, decreases in a semi-sitting position. Gradually, hypesthesia develops — a decrease in sensitivity, perceived by patients as numbness.
Motor disorders manifest themselves in the form of slight weakness in the distal parts of the lower limb, rapid fatigue when walking. As the pathological process progresses, the symptoms become bilateral. The aggravation of paresis causes significant difficulties in independent movement. A disorder of the sensitivity of the external genitals leads to a violation of the sexual sphere: anorgasmia is formed in women, erectile dysfunction in men. The function of the pelvic organs suffers, patients lose the feeling of fullness of the bladder, rectum. The result of the lack of urge to urinate, defecation is urinary retention, chronic constipation.
Complications
With the progression of the lesion against the background of lack of treatment, the patient becomes disabled due to walking disorders. Overflow of the bladder due to the lack of timely urination can be complicated by the formation of a diverticulum, stagnation of urine – infection with the development of urethritis, cystitis, ascending pyelonephritis. Prolonged stoolage is accompanied by the absorption of toxic substances in the intestine, which leads to general intoxication of the body. Urgent complications requiring urgent medical care are acute urinary retention and fecal blockage.
Diagnostics
In the initial period, cauda equina syndrome can be misdiagnosed as femoral nerve neuropathy, sciatica, lumboishialgia. The fallacy of such a diagnosis is indicated by the bilateral nature of the changes, the dysfunction of the pelvic and genital organs, the features of the neurological examination data. In order to clarify the diagnosis and identify causal pathology, the following examinations are carried out:
- Neurological examination. The neurologist determines the lower distal mono- or paraparesis, muscle hypotension, atrophic changes. Achilles, anal, bulbo-cavernous (in men) reflexes are significantly reduced or absent. Hypesthesia is detected in zones corresponding to different roots, which indicates the defeat of several lumbosacral nerves at once.
- Computed tomography. CT of the spine is more accurate than radiography, allows you to confirm the presence of bone anomalies, narrowing of the spinal canal. The disadvantage of the study is poor visualization of soft tissue structures.
- Magnetic resonance imaging. MRI of the lumbar spine visualizes hematomas, neoplasias, intervertebral hernias, makes it possible to assess the degree of narrowing of the spinal canal. MRI poorly displays the state of bone structures, so it is used in addition to CT.
- Lumbar puncture. The absence of cerebrospinal fluid during spinal puncture (dry puncture) is observed with a complete block of the cerebrospinal space due to the obstruction of the canal by a large tumor, hernia. Hemorrhagic staining of the cerebrospinal fluid indicates hemorrhage. Neoplasia is characterized by a significant increase in protein in the cerebrospinal fluid, arachnoiditis, myelitis — inflammatory changes.
- Histological examination. It is carried out in the case of a neoplasm to verify its type, determine the degree of malignancy. The study is performed intraoperatively, followed by a control analysis of the removed material.
Cauda equina syndrome must be differentiated from polyneuropathy, mononeuropathy of the nerves of the lower extremity, manifestations of lumbosacral plexitis. It is also necessary to distinguish between the syndrome of discogenic, tumor, traumatic, vascular etiology. In differential diagnostics, the results of magnetic resonance imaging and other additional research methods are of great importance.
Treatment
Therapeutic measures are aimed at eliminating the cause of the disease, decompression of nerve roots, restoration of their functions. Often conservative methods of therapy are insufficient, they are used in combination with surgical treatment. Thus, the treatment consists of the following components:
- Conservative therapy. Provides for the use of analgesics, glucocorticosteroids, muscle relaxants. Severe pain syndrome is an indication for the appointment of therapeutic blockades with the introduction of local anesthetics and corticosteroids. With urinary retention, catheterization of the bladder is performed, with constipation — cleansing enemas.
- Surgical intervention. Taking into account the indications, operations are performed to remove the tumor, hematoma, discectomy is indicated in the presence of a herniated disc. The purpose of surgical intervention may be the correction of a congenital anomaly, stabilization of the spine. If radical removal of neoplasia is not possible, palliative operations are performed to expand the spinal canal by laminectomy. The indication for urgent intervention is pelvic organ dysfunction, increasing lower paraparesis.
- Rehabilitation. It is necessary for the most complete restoration of the lost neurological functions. It is combined with the appointment of vascular, neurometabolic drugs. It is carried out by the efforts of rehabilitologists, massage therapists, physiotherapists, physical therapy doctors. Tumor processes are a contraindication to physiotherapy procedures, massage.
Prognosis and prevention
The success of the disease therapy is determined by its etiology, the prevalence of the process, the duration of the course without therapeutic measures. Timely treatment makes it possible to almost completely eliminate the neurological deficit. Without adequate therapy, irreversible changes occur over time in the affected trunks of the ponytail, the restoration of their function becomes impossible. There are no specific methods of prevention of this pathology. General measures include injury prevention, exclusion of oncogenic effects, compliance with operating techniques during interventions on the lumbar and sacral spine.