Hemorrhage affecting the spinal cord is rare. Spinal cord hemorrhage can be divided based on etiology, into two types: (1) traumatic and (2) non-traumatic. It can also be divided based on the compartment into which the hemorrhage occurs, namely: (1) intramedullary (including hematomyelia), (2) subarachnoid (SAH), (3) subdural (SDH), and/or (4) epidural (EDH).[1] Spinal cord hemorrhage is most commonly caused by trauma, vascular malformations, or bleeding diatheses. Spinal cord hemorrhage usually presents as sudden, painful myelopathy, which may reflect the anatomic level of the hemorrhage.[2]
For perfusion, three longitudinal vessels form an anastomotic network that supplies the spinal cord: two posterior spinal arteries, and the anterior spinal artery. Blood flows from the anterior spinal artery into medullary branches of the intradural vertebral arteries, and subsequently into segmental radiculomedullary arteries. The blood flow to the posterior spinal arteries originates from intradural vertebral arteries, which are from medullary segments of the posterior inferior cerebellar arteries and segmental radiculopial arteries. Blood flow to the lower portion of the spinal cord (T8–L3) is supplied by a large radicular artery with somewhat variable positioning, termed the Artery of Adamkiewicz.[1]
The cross-sectional blood supply of the spinal cord can be divided into (1) central and (2) peripheral systems, which supply the grey and white matter, respectively (with some degree of overlap). The central perfusion region receives blood supply from the anterior spinal artery, which forms the central sulcus artery and courses into the ventral median sulcus and supplies the grey matter of spinal cord. The posterior spinal arteries give rise to the “vasocorona,” which eventually branches into peripheral arteries and mainly supplies the white matter of the spinal cord.[1]
Anterior and posterior median spinal veins drain the anterior and posterior regions of the spinal cord, respectively. The pial surface and superficial regions of the spinal cord are drained by radial veins and the coronal venous plexus.[1, 3, 4]
The most common cause of spinal cord hemorrhage is traumatic injury. With trauma, shear forces acting upon the spinal cord and surrounding structures may lead to hemorrhage and vascular damage. These may in turn cause additional injury through edema and infarction. Autopsy studies demonstrate the hemorrhagic necrosis of the spinal cord that is caused by trauma. In non-traumatic cases, vascular malformations and coagulopathies are the most common etiologies, in almost equal proportions.
Hematomyelia is defined as the presence of a well-defined focus of hemorrhage within the spinal cord itself. Trauma is the leading cause of hematomyelia. Hematomyelia more commonly involves the cervical rather than thoracic or lumbar spinal cord. In hematomyelia, blood tends to dissect longitudinally above and below the hemorrhage, disrupting grey matter more than white matter. The most common location is within the central grey matter of the spinal cord, centered at the point of mechanical impact. Ischemia results from mass effect and disruption of blood flow, which may cause infarction of the spinal cord. Such infarction also usually involves the grey matter to greater extent than the white matter.[1, 5, 6]
Hematomyelia can also be spontaneous, and has been reported in patients with hereditary coagulation disorders and/or patients on antiplatelet and anti-coagulation therapies. Intramedullary spinal cord tumors, both primary CNS and metastatic (especially renal cell carcinoma), can also bleed and lead to hematomyelia.[7, 8] The causes for bleeding within the spinal cord are summarized in Table 1.
Table 1. Summary of intramedullary spinal cord hemorrhage etiologies, with history and associated clues, common imaging findings, and representative management. Adapted from Leep, Hunderfund, & Wijdicks (2009).
View Table | See Table |
Hemorrhage due to a vascular malformation (such as arteriovenous malformation [AVM], cavernoma, or spinal arteriovenous fistulas [AVF]), is the second most common cause of intramedullary spinal cord hemorrhage. Vascular malformations can also lead to spinal subarachnoid hemorrhage (SAH). A small percentage of spinal AVMs are associated with Osler-Webber-Rendu disease.
Spinal cavernomas are much less common than cranial cavernomas. Up to 45% of patients with a spinal cavernoma will have at least one cranial cavernoma.[1] Spinal AVFs often arise from the posterior aspect of the spinal cord, and most commonly occur in the thoracic region. AVFs may cause venous congestion, with lack of adequate drainage of the spinal cord. The subsequent congestive ischemia usually involves the posterior sensory elements of the spinal cord, but can progress to paralysis. Spinal AVFs do not typically bleed, but hemorrhages due to AVFs (when they do occur) are intramedullary in most cases.
Foix-Alajouanine syndrome results from compression of the spinal cord due to increased venous pressure (usually due to AVF; less commonly AVMs) and often involves acute to sub-acute progression of neurological deficits from spastic paraplegia to flaccid paralysis, loss of sphincter tone, and ascending sensory loss.[9]
Spinal subarachnoid hemorrhage (SAH) may cause symptoms due to blood in the subarachnoid space, or blood dissecting into the spinal cord or along nerve root sheaths. Causes of spinal cord SAH include vascular malformations and spinal aneurysms, however, hemorrhagic spinal tumors, and rarely, extension of cranial SAH, may present as spinal SAH. Spinal aneurysms are usually located in the cervical and thoracic regions and are most often dissecting or fusiform in morphology. It is also possible for a blood clot to form in the spinal subarachnoid space, forming a subarachnoid space hematoma. This is recognized as a separate entity and usually presents with gradual compression of the spinal cord rather than acute pain and paralysis. The cause for this is also different from SAH, and is usually associated with procedures such as lumbar puncture or epidural anesthesia, especially in patients on anticoagulation therapy.[1, 10]
Spinal epidural hemorrhage (EDH) is usually due to trauma or iatrogenic etiologies including spinal surgeries, obstetrical birth trauma, lumbar puncture, spinal manipulations, and epidural procedures. The epidural space is the most common compartment for bleeding affecting the spinal cord.[1]
Spinal subdural hemorrhage (SDH) occurs less commonly than spinal EDH, however, it presents similarly and is also usually due to trauma, or iatrogenic due to surgical procedures or anticoagulation.[11, 12]
Spinal SDH and EDH may cause symptoms and signs of spinal cord compression, corresponding (or caudal) to the level of the hematoma. The timing of symptom onset and progression may vary based on the rate of hematoma expansion. Unlike cranial hematomas, the vascular source for both spinal SDH and EDH is usually venous.
Symptoms may develop more slowly in cases of spinal SDH due to a slower rate of bleeding.[13, 14] Otherwise, the features distinguishing EDH from SDH include the evidence from imaging studies, usually MRI. Epidural hematomas are generally located dorsally, due to the firm adherence of the thecal sac to the posterior longitudinal ligament at the ventral aspect of spinal canal. They usually have characteristic biconvex shape on imaging, with tapering superior and inferior boarders in sagittal view. Spinal SDHs, on the other hand, are often located ventral to the spinal cord.
Intrasyringal hemorrhage may rarely occur in patients with pre-existing syringomyelia. Conditions known to predispose to syrinx formation include Arnold-Chiari malformation, meningitis, trauma, scoliosis and trauma. In rare cases, such a hemorrhage may occur spontaneously.[2]
Spontaneous spinal EDH has an incidence of 0.1 per 100,000 person-years. Spinal EDH occurs at least 4 times more commonly than spinal subdural hemorrhage. Spinal SAH accounts for less than 1% of all CNS subarachnoid hemorrhages. Minor trauma is a possible causative factor for most of these cases.[15]
Otherwise, the precise frequencies and breakdown of spinal cord hemorrhages by type and/or cause are difficult to find in the literature. As mentioned, the most common etiology is trauma, followed by iatrogenic, neoplastic, and vascular malformation causes.[1]
Hemorrhage of the spinal cord can lead to irreversible myelopathy (including conus medullaris and cauda equina syndromes) and/or radiculopathy, depending on the location and the extent of the hemorrhage. The presence of intramedullary hemorrhage and extended segments of edema have been associated with clinically complete spinal cord injury. Prognosis may often be poor due to the added effect of reduced perfusion, edema, and secondary injury.[16, 17]
The incidence of hematomyelia, spinal SAH, and spinal EDH is higher in males than in females. Spinal SDH is more common in women, with a female-to-male ratio of 2:1.[18, 19]
Spinal EDH has a bimodal distribution, with peaks during childhood and the fifth and sixth decades of life. Spinal EDH is most common in the cervical region in children and in the thoracic and lumbar regions in adults. Spinal SDH predominates in the sixth decade.[20, 21, 22]
Prognosis varies but generally is correlated with severity of deficit, particularly the “completeness” of the spinal cord injury. The clinical outcome of spinal cord hemorrhage also depends on the type (i.e., the compartment and level involved) and acuity of the symptoms.[27] Several studies have reported that more extensive and acute hemorrhages result in higher morbidity and mortality even with prompt intervention. Similarly, intramedullary and subarachnoid spinal hemorrhages are associated with higher morbidity and mortality.[2, 26, 28, 29, 30] Prompt diagnosis and intervention is advocated if possible, in an effort to improve outcome regardless of hemorrhage etiology.[1, 9, 16, 24, 28]
The presentation of all types of spinal cord hemorrhage varies based on the acuity of the hemorrhage as well as the longitudinal and cross-sectional extent of the hemorrhage and its rate of expansion. The following descriptions are typical, but not absolute.
Clinical presentation may include the following:
Clinical presentation may include the following:
Clinical presentation may include the following:
Physical examination may reveal the following:
Physical examination may reveal the following:
Physical examination may reveal the following:
Causes may include the following:
Causes may include the following:
Causes may include the following:
Causes may include the following:
The following laboratory studies may aid in diagnosis:
Cervical, thoracic, or lumbar spinal MRI is the preferred test to confirm presence and delineate location of hemorrhage.
May indicate underlying pathology, for instance, with enhancement.
An alternative when clinical suspicion is high and MRI is not available, or the patient who is not able to tolerate MRI. CT myelogram shows fluid collections (such as EDH, SDH) and is also useful for CSF leak detection. In general, CT is not as sensitive as MRI for non-boney structures. CT alone may or may not show acute hematomyelia.
If hemorrhage extends into the cerebrospinal fluid (CSF), the CSF sample is usually bloody appearing or xanthochromic, and protein content is increased. Xanthochromia is the yellowish discoloration of CSF due to the presence of bilirubin, which is the result of RBC lysis and subsequent heme breakdown occurring over time. An initial “bloody tap” (in the absence of a preceding hemorrhagic event) should clear and not be xanthochromic.
Xanthochromia may be present as early as 4 hours post hemorrhage, but usually takes about 12 hours to occur, after the appearance of blood within the subarachnoid space. It may persist up to four days after the original hemorrhage. Detection of xanthochromia is done by visual inspection pre- and post CSF centrifugation, which eliminates red blood cells. Mass spectroscopy of CSF may also be useful, for detection of bilirubin and to rule out other possible causes of xanthochromia (such as high protein content, or melanin). This is especially useful when the suspicion for SAH is high and the imaging findings are negative due to the time elapsed since the hemorrhage, or with smaller amounts of blood.[23]
This may be helpful in delineating the size, location, configuration, and blood flow of a spinal vascular malformation, such as AVM or AVF.
Medical therapies for spinal cord hemorrhage are limited.
If the bleed is caused by a coagulopathy, reversal of the bleeding tendency is crucial. Examples include fresh frozen plasma and vitamin K or prothrombin complex concentrate for warfarin-induced bleeds, protamine sulfate for heparin-induced bleeds, platelet transfusions for thrombocytopenia, specific clotting factor concentrates or fresh frozen plasma for clotting factor deficiencies such as hemophilia and Christmas disease. The optimal treatment to reverse the effects of the new oral anticoagulants is unknown.
Another potential medical treatment, drug therapy for cord edema, is unproved.
Depending on etiology (deduced from history, lab work, and imaging) and clinical findings (such as the presence or progression of neurological deficits), surgery may be indicated for hemorrhage affecting the spinal cord. Surgery would not be expected to reverse the damage already caused by infarction.
In general, surgery should be strongly considered in spinal subdural hemorrhage and epidural hemorrhage. Patients with these conditions may benefit from immediate decompressive operation if associated neurological signs and symptoms are present (e.g., weakness, paresthesiae, loss of sphincter control, positive Babinski, etc.).[24, 25]
It should be noted, however, that even emergency surgery cannot guarantee full return of function, and management decisions are made on a case-by-case basis. If coagulopathy is present, it may need to be corrected, and the patient may require medical stabilization.
Spinal vascular lesions may be approached by catheter-based interventional techniques, such as embolization or coiling.
Endovascular embolization for AVF or combined embolization followed by surgical resection for AVM may be indicated for patients with spinal SAH.[1] The decision of embolization vs. surgery or whether or not to perform any intervention is complex and depends on the presence of neurologic symptoms, acuity of symptom presentation and hemorrhage, location of the AVM (ventral vs. dorsal; proximity to critical spinal cord tracts), and location and number of feeding arteries and draining veins, presence of nidus, and any associated fistulas.
Even if significant obliteration is achieved by endovascular embolization, an AVM may still require operative resection. In the case of partial embolization, surgery is usually performed. The long-term clinical outcome of patients treated for AVMs (by endovascular intervention, surgery, or both) varies according to the nidus versus fistulous type of AVM. Patient outcomes are usually better in the latter type, which may depend on the degree of obliteration, and inherent hemodynamic differences between the two types.[26]
The following consultations may prove helpful:
The primary goal of pharmacotherapy for patients with hemorrhage affecting the spinal cord is to reverse the effect of anticoagulants (in individuals taking such medications), with the goal of limiting any additional bleeding. Such agents and their antidotes are described in Table 2.
Table 2. Commonly used anticoagulants and antiplatelet agents, and the antidotes used to reverse their effects. Antidotes may be used in patients who have had a hemorrhage, are actively bleeding, in preparation for surgical intervention, or are at high risk for further hemorrhage.
View Table | See Table |
Attempts to treat spinal cord hemorrhage with medications such as mannitol or corticosteroids have not been tested in randomized, double-blind studies.
If spinal cord hemorrhage presents a situation similar to spinal cord injury, high-dose corticosteroids (e.g., methylprednisolone) might be beneficial, but this needs to be weighed against possible side effects.
Spasticity secondary to spinal cord hemorrhage is treated in similar ways to spasticity secondary to other causes of traumatic spinal cord injury, or multiple sclerosis. Drugs include baclofen, tizanidine, and diazepam.
Pain following spinal cord hemorrhage (other than pain secondary to spasticity), is treated similarly to other neuropathic pain syndromes such as those in multiple sclerosis. Drugs may include gabapentin, pregabalin, amitriptyline, and/or carbamazepine.
Bladder complications of spinal cord hemorrhage also receive treatment similar to those of spinal cord injury / multiple sclerosis. Consultation with a urologist may be necessary. Drug therapy with anticholinergic agents may be beneficial for reflex uninhibited bladder (i.e., failure to store), and intermittent self-catheterization is essential in patients with inability to void (i.e., failure to empty).
Clinical Context: Neutralizes heparin effects by forming a salt.
Clinical Context: Promotes liver synthesis of clotting factors that in turn inhibit warfarin effects.
Once the patient with spinal cord hemorrhage has been treated, whether medically, via interventional radiology, or surgery, rehabilitative care can begin, depending on the nature of the spinal cord injury. Usually such care is initiated in an inpatient rehabilitation setting.
After the patient is discharged from inpatient care, outpatient therapies continue. Medical treatments are frequently necessary for the late complications of spinal cord hemorrhage, especially spasticity, pain, and neurogenic bladder.
It is not unusual for patients to have residual myelopathy, weakness, or bladder dysfunction even after receiving optimal intervention to stop the cause of hemorrhage and even decompress the spinal cord.
As with other types of spinal cord injury, outpatient follow-up is also important to identify any new or unexpected sequelae (such as urinary tract infection; deep venous thrombosis), and to monitor the progress of recovery and rehabilitation. Patients may experience significant improvements in strength and sensation, but these again depend on factors such as extent and level of injury, and existing comorbidities.[29, 31, 32, 33, 34, 35, 36, 37]
Given the varying etiologies of spinal cord hemorrhage, efforts at prevention would depend on the causative factor. For instance, the pros and cons of lumbar puncture in patients with hematologic disorders or in those treated with anticoagulants (as well as the risks of reversing anticoagulation) should be carefully considered.
Etiology History clues Imaging findings Management Spinal trauma MVA, falls, sports Associated injury to bony and/or ligamentous structures Spine stablization/decompression; debated rolde of steroids Spinal AVM Sudden onset of neurological deficits, severe back pain, and meningismus Abnormal vessels with flow voids Endovascular embolizations vs. surgical resection Spinal cavernoma Family or personal history of cavernomas “Popcorn”-like lesions with associated hemosiderin rings Possible surgery if recurrent bleeds Coagulation deficits History of warfarin, heparin, or other medications; elevated PTT or INR; sudden onset of deficits; genetic causes; liver or autoimmune disease; malignancy Possible air-fluid levels Anticoagulation reversal; correction of deficient coagulation factor(s); treatment of underlying problem Spinal cord tumor Progressive neurological deficits; known history of cancer (especially renal cell carcinoma) Mass effect with spinal cord enlargement; contrast enhancement Surgical resection; radiation for malignancy
Anticoagulant/antiplatelet agent Antidote Heparin (UFH and LMWH) Protamine sulfate Warfarin Vitamin K, fresh frozen plasma (FFP), prothrombin protein concentrate (PPC), Factor VII concentrateNote: PPC and Factor VII have effects within minutes; FFP and Vitamin K require hours–days to take full effect. Direct factor X inhibitors (Fondaparinaux, Apixaban) Four factor PCC
Oral activated charcoal
Andexanet alfaNovel oral anticoagulants (NOAC) Four factor PPC
Oral activated charcoal
Idarucizumab (Praxbind) for dabigatran reversal
+/- platelet transfusion for clopidogrel and ticagrelor