Isolated monoparesis following stroke

Isolated Lower Limb Weakness Following Hemorrhagic Stroke: A Case Report

Isolated limb weakness (monoparesis) has many possible etiologies. Although often assumed to be of a peripheral cause, it can be of central origin. This article describes a case from the Emergency Department of left lower limb weakness in a walk-in male patient on no medications, who had a 50-pack-year smoking history, type II diabetes, and asymptomatic atrial fibrillation. The patient had no history of previous episodes or trauma. His vitals were normal, and his speech and facial function were intact. The patient had full function of his upper limbs, no sensory deficits, and equal reflexes bilaterally. The singular clinical finding was decreased strength in the left leg compared to the right. Imaging revealed a right frontal intraparenchymal hemorrhage, which remained stable throughout his hospital admission. His muscle weakness was significantly improved upon discharge. In general, strokes can present with a variety of symptoms, which increase the risk of misdiagnosis. Monoparesis can be the singular sign of a stroke, and it is more common in the upper than the lower limbs.

Ischemic stroke cases presenting with hand weakness mimicking peripheral neuropathy

Pure motor monoparesis due to ischemic stroke involving a single extremity is a rare condition that can be easily misdiagnosed. Herein, we present three cases with isolated upper extremity monoparesis. All of our patients had weakness in the left hand. They were previously evaluated in other centers and were diagnosed with peripheral neuropathy by electromyography. When patients whose complaints did not resolve were admitted to our clinic, we performed electromyography again and observed that it was normal. Hereupon, we detected ischemic infarctions in cranial magnetic resonance imaging that would explain the patients' complaints. Isolated monoparesis mimicking peripheral neuropathy is a rare symptom in stroke patients. Pure motor monoparesis should be kept in mind in every patient presenting with acute-isolated monoparesis, and neuroradiological imaging should be performed.

Acute reversible monoparesis in multiple neurocysticercosis: A case report and review of literature

Focal neurological deficit like monoparesis due to cortical lesions is a rare entity. In spite of the common presentations like seizures and headaches in neurocysticercosis, occurrence of reversible monoparesis is an atypical phenomenon. Even in the absence of infarct or hemorrhages, manifestation of neural deficit due to compressive effect only is an interesting finding. And on top of that, reversible nature of the deficit in space occupying lesion is a rare occurrence in the existing literature. Here, we describe a known case of neurocysticercosis with reversible acute monoparesis secondary to multiple neurocysticercosis. The variations with which neurocysticercosis can present broaden our understanding in its pathophysiology and management protocol.

Selective Hand Motor Cortex Lesions Masquerading as "Pseudoperipheral Nerve Palsy"

Strategic cortical lesions involving the hand motor cortex (HMC) presenting acutely as distal upper limb pure motor weakness certainly do need to be differentiated on clinical grounds from “pseudoperipheral palsy.” This rare phenotype can imitate peripheral motor nerve deficits and should not be easily overlooked. The isolated “central hand and finger weakness” presenting as an acute onset of varying combinations such as pseudomedian, pseudoradial, and/or pseudoulnar nerve palsy is intriguing to the novice. In literature, this phenotype has been reported solely to result from cortical cerebral infarction and documented to occur in <1% of all ischemic strokes. The apropos of six “unforgettable patients” here highlights the heterogeneous pathophysiologic etiologies and mechanisms that included not only the conventional stroke risk factors but also hyperhomocysteinemia, common carotid artery thrombosis due to hyperhomocysteinemia and severe iron-deficiency anemia, biopsy-proven giant cell arteritis (GCA), cerebral metastasis, and dilated cardiomyopathy-related left ventricular thrombosis. Physicians and neurologists alike, as clinicians, need to be familiar with the peculiarities and clinical presentations of central hand control network cortical lesions.

[Poststroke motor and cognitive impairments: clinical features and current approaches to rehabilitation]

Stroke is one of the most common neurological diseases with high morbidity, disability and mortality, which is an urgent medical and social problem. Clinically, stroke, depending on its nature and location, causes a wide range of neurological disorders, including movement disorders, as well as a variety of cognitive and neuropsychiatric disorders. There is an emerging need for new approaches to manage patients with cerebrovascular diseases during the pandemic of COVID-19. Rehabilitation measures for the correction of motor and cognitive impairments are very diverse. The use of drugs stimulating the production of neurotrophic factors is considered as a promising direction of pharmacotherapy. Cerebrolysin promotes significant regression of motor and cognitive impairments in the acute and recovery period of ischemic stroke. Based on the data of clinical studies, Cerebrolysin is included in the guidelines for the rehabilitation of patients with stroke in Canada and Germany.

Symptoms and probabilistic anatomical mapping of lacunar infarcts

Background

The anatomical distribution of acute lacunar infarcts has mainly been studied for supratentorial lesions. In addition, little is known about the association with distinct stroke symptoms, not summarized as classical lacunar syndromes. We aimed to describe the spatial lesion distribution of acute supra- and infratentorial lacunar infarcts and their association with stroke symptoms in patients eligible for thrombolysis.

Methods

All patients enrolled in the WAKE-UP trial (efficacy and safety of magnetic resonance imaging [MRI]-based thrombolysis in wake-up stroke) were screened for lacunar infarcts on diffusion-weighted imaging (DWI). The relationship between the anatomical distribution of supra- and infratentorial lacunar infarcts, their demographic characteristics and acute stroke symptoms, defined by the National Institutes of Health Stroke Scale (NIHSS) score, were correlated and compared.

Results

Maps of lesion distribution from 224 lacunar infarct patients (76 [33.9%] females, mean age [standard deviation] of 63.4 [11.5] years) were generated using computational image mapping methods. Median infarct volume was 0.73 ml (interquartile range [IQR] 0.37–1.15 ml). Median NIHSS sum score on hospital arrival was 4 (IQR 3–6). 165 (73.7%) patients had lacunar infarcts in the supratentorial deep white or grey matter, while 59 (26.3%) patients had infratentorial lacunar infarcts. Patients with supratentorial lacunar infarcts presented with a significantly lower occurrence of deficits in the NIHSS items gaze (p < 0.001) and dysarthria (p = 0.008), but had more often a paresis of the left arm (p = 0.009) and left leg (p = 0.068) compared to patients with infratentorial infarcts.

Conclusions

The anatomical lesion distribution of lacunar infarcts reveals a distinct pattern and supports an association of localization with different stroke symptoms.

Trial registration

NCT01525290.

['Stroke chameleons']

The diagnosis of acute stroke should be correct and early that allows physician planning the most effective treatment strategies (reperfusion therapy, undifferentiated (basic) treatment, early secondary prevention). However, stroke symptoms can be atypical and similar to some other (non-vascular) event. It can significantly complicate the clinical diagnosis of stroke and decrease the patient's chances for effective treatment. A stroke should be suspected in every patient with acute onset of neurological symptoms, especially when the patient has the 'vascular' risk factors. Furthermore it is important to remember that negative CT-scan data and/or MRI data do not exclude the presence of not only ischemic stroke but also hemorrhagic stroke. The article describes the main variants of strokes with atypical symptoms (strokes-chameleons), emphasizes the importance of careful clinical examination, provides supportive differential diagnostic criteria and discusses limitations of neuroimaging methods.

A case report of isolated distal upper extremity weakness due to cerebral metastasis involving the hand knob area

Background

Unilateral weakness of an upper extremity is most frequently caused by traumatic nerve injury or compression neuropathy. In rare cases, lesion of the central nervous system may result in syndromes suggesting peripheral nerve damage by the initial examination. Pseudoperipheral hand palsy is the best known of these, most frequently caused by a small lesion in the contralateral motor cortex of the brain. The ‘hand knob’ area refers to a circumscribed region in the precentral gyrus of the posterior frontal lobe, the lesion of which leads to isolated weakness of the upper extremity mimicking peripheral nerve damage. The etiology of this rare syndrome is almost exclusively related to an embolic infarction.

Case presentation

We present the case of a 70-year-old male patient with isolated left sided upper extremity weakness and clumsiness without sensory disturbance suggesting a lesion of the radial nerve. Nerve conduction studies had normal results excluding peripheral nerve damage. Neuroimaging (cranial CT and MRI) detected 3 space occupying lesions, one of them in the right precentral gyrus. An irregularly shaped tumor was found by CT in the left lung with multiple associated lymph node conglomerates. The metastasis from this mucinous tubular adenocarcinoma with solid anaplastic parts to the ‘hand knob’ area was responsible for the first clinical sign related to the pulmonary malignancy.

Conclusions

Pseudoperipheral palsy of the upper extremity is not necessarily the consequence of an embolic stroke. If nerve conduction studies have normal results, neuroimaging – preferably MRI – should be performed, as lesion in the hand-knob area of the precentral gyrus can also be caused by a malignancy.

Clinching the cause: A review of foot drop secondary to lumbar degenerative diseases

Foot drop is defined as weakness on dorsiflexion of the foot. The top two most common etiologies for foot drop include lumbar degenerative disease and common peroneal nerve injury. This review provides "updates" on understanding the lumbar etiologies of foot drop. Since the publication of "Preoperative motor strength and time to surgery are the most important predictors of improvement in foot drop due to degenerative lumbar disease" in the Journal of Neurological Sciences, three cohort studies have been published on spinal causes of foot drop. Classification, clinical features, diagnosis, and pathogenesis that may 'clinch' the cause of foot drop are discussed in the context of these recent publications.

Lesion Pattern, Mechanisms, and Long-Term Prognosis in Patients with Monoparetic Stroke: A Comparison with Nonmonoparetic Stroke

Background

Monoparetic stroke is rare but could be misdiagnosed as peripheral neuropathy. We investigated the prevalence, lesion pattern, stroke mechanism, and long-term prognosis in patients with monoparetic stroke.

Methods

586 acute ischemic stroke patients (including 31 with monoparesis) were studied. Monoparetic stroke was defined as a motor deficit in either an arm or a leg but without facial weakness or speech disturbance. Median follow-up period was 32.0 months. Kaplan-Meier survival curves, log-rank tests, logistic regressions, and Cox proportional hazards models were used for clinical outcome analyses.

Results

The mean age (313 men and 273 women) was 67.6 years. Among monoparetic patients, most had cortical (80.6%) and multiple (64.5%) lesions. The main stroke mechanisms were cardioembolism (38.7%) and large artery atherosclerosis (29.0%). Precentral gyrus with additional regions was most frequently involved in monoparesis (45.2%). Upper motor neuron signs were found in only 11 patients (35.5%). Compared with the nonmonoparetic group, these patients had better functional outcomes (6-month modified Rankin scale ≤2) and long-term survival but had comparable risks for further vascular events, including stroke recurrences.

Conclusions

Although monoparetic stroke may have a better functional outcome, the risk of the further vascular event seems similar to nonmonoparetic stroke.

Pseudoradial Nerve Palsy Caused by Acute Ischemic Stroke

Pseudoperipheral palsy has been used to characterize isolated monoparesis secondary to stroke. Isolated hand nerve palsy is a rare presentation for acute cerebral stroke. Our patient presented with clinical features of typical peripheral radial nerve palsy and a normal computed tomography scan of the head, which, without a detailed history and neurological examination, could have been easily misdiagnosed as a peripheral nerve lesion deferring further investigation for a stroke. We stress the importance of including cerebral infarction as a critical differential diagnosis in patients presenting with sensory-motor deficit in an isolated peripheral nerve pattern. A good history and physical exam can differentiate stroke from peripheral neuropathy as the cause of radial nerve palsy.

Isolated Painless Foot Drop due to Cerebral Infarction Mimicking Lumbar Radiculopathy: A Case Report

Although they usually originate from peripheral problems, foot drop is caused by lesions affecting the neural pathway related to dorsiflexor muscles, whether of central or peripheral origin. We present a patient with sudden isolated foot drop caused by a small infarct in the primary motor cortex mimicking a peripheral origin. This report indicates that patients presenting isolated foot drop should be managed carefully and the possibility of both central and peripheral causes should be considered. To our knowledge, this is the first report of sudden isolated foot drop caused by a cortical infarction mimicking lumbar radiculopathy.

Acute foot drop syndrome mimicking peroneal nerve injury: an atypical presentation of ischemic stroke

Foot drop syndrome is a frequent neurologic condition usually caused by peroneal nerve damage. On rare occasions, foot drop may present as the single neurologic manifestation of intracranial lesions. We presented a 43-year-old man admitted to our hospital with acute weakness in the dorsiflexion of his right foot that appeared 3 days before admission. Brain magnetic resonance imaging diffusion-weighted sequence revealed a small area of restricted diffusion in the left frontal cortex. Three months later, his motor deficit had completely improved (modified Rankin scale score = 0). To our knowledge, this is the second report of sudden isolated foot drop caused by a cortical infarction.

Hemi- and monoataxia in cerebellar hemispheres and peduncles stroke lesions: topographical correlations

Limb ataxia of sudden onset is due to a vascular lesion in either the cerebellum or the brainstem (posterior circulation, PC, territory). This sign can involve both the upper and the lower limb (hemiataxia) or only one limb (monoataxia). The topographical correlates of limb ataxia have been studied only in brainstem strokes. Therefore, it is not yet known whether this sign is useful to localize the lesion within the entire cerebellar system, both the cerebellar hemisphere and the cerebellar brainstem pathways. Limb ataxia was semi-quantified according to the International Cooperative Ataxia Rating Scale in 92 consecutive patients with acute PC stroke. Limb ataxia was present in 70 patients. Four topographical patterns based on magnetic resonance imaging findings were identified: picaCH pattern (posterior inferior cerebellar artery infarct); scaCH pattern (superior cerebellar artery infarct); CH/CP pattern (infarct involving both the cerebellum and the brainstem cerebellar pathways); and CP pattern (infarct involving the brainstem cerebellar pathways). Hemiataxia was present in (47/70; 67.1%) and monoataxia in (23/70; 32.9%) of patients. Monoataxia involved the upper limb in (19/70; 27.1%) and the lower limb in (4/70; 5.7%) of patients. Limb ataxia usually localized the lesion ipsilaterally (picaCH, scaCH, CH/CP, and CP patterns involving the medulla and sometimes the pons) (53/70; 75.7%), but it might be due also to contralateral (CP pattern involving the pons or midbrain) (16/70; 22.9%) or bilateral lesions (1/70). Limb ataxia usually localizes the lesion ipsilaterally but the infarct might be sometimes contralateral. The occurrence of monoataxia may suggest that the cerebellar system is somatotopically organized.

Pure Motor Monoparesis in the Leg due to a Lateral Medullary Infarction

A 76-year-old man with essential hypertension abruptly presented with slight left-sided leg weakness, despite normal strength in the other extremities. Left-sided Babinski's reflex was detected. There were no other neurologic abnormalities. Cranial magnetic resonance imaging demonstrated a small infarction in the lower lateral medulla oblongata on the left side. Cranial magnetic resonance angiography demonstrated an absence of flow of the left vertebral artery. He became asymptomatic within 10 days under intravenous antiplatelet agent. The corticospinal tract fibers innervating the lower extremity caudal to the pyramidal decussation might be involved. We emphasize that this is a first reported case of pure motor monoparesis in the leg due to lateral medullary infarction.

Atypical presentations of acute cerebrovascular syndromes

Correct diagnosis of acute stroke is of paramount importance to clinicians to enable selection of correct treatments and to ensure prevention of acute complications, including recurrent stroke. Timely diagnosis can be difficult in some cases because patients with acute stroke can present with atypical or uncommon symptoms that suggest another cause altogether. Publications on these patients suggest that the following strategies could help to reduce misdiagnosis. First, clinicians should suspect stroke in any patient with abrupt onset of neurological symptoms. Second, clinicians should be aware that some patients will initially present with various uncommon and atypical stroke symptoms. Third, a complete and systematic neurological examination should be routinely done in patients presenting with acute neurological symptoms because this might shed light on the true nature of the problem. Finally, clinicians should be aware that even with the most sophisticated neuroimaging tests, stroke might be missed in the early hours after the event.

Fractional arm weakness as presentation of stroke due to posterior borderzone infarct: A report of two cases

A 41-year-old male presented with acute onset weakness of the left hand. Magnetic resonance imaging (MRI) of the brain showed hyperacute infarct in the right middle cerebral artery (MCA)–posterior cerebral artery (PCA) watershed territory. Magnetic resonance angiography (MRA), Doppler ultrasonography, and digital subtraction angiography revealed severe right internal carotid artery (ICA) stenosis. The patient underwent carotid endarterectomy. The second patient was a 48-year-old male with acute onset right wrist drop. MRI of brain showed acute infarct in the left MCA–PCA watershed territory. MRA of brain and neck, Doppler ultrasonography of the neck vessels, and echocardiography were normal. Both the cases were not initially considered strokes by the referring physicians. Isolated hand palsy is a rare presentation of stroke, often mistaken for peripheral lesion. Fractional limb weakness as a presentation of acute ischemic stroke due to borderzone infarction involving parietal lobe is a rarely reported entity.

Pure motor upper limb weakness and infarction in the precentral gyrus: mechanisms of stroke

BACKGROUND

Pure arm monoparesis is an uncommon presentation of stroke. Localization of the lesions is variable, including cortical, subcortical or deep brain infarcts. No particular risk factors or unifying mechanisms have been clearly identified.

METHODS

Seven patients (5 women, 2 men) presented with isolated arm weakness and brain magnetic resonance imaging (MRI) documented an infarct in the precentral gyrus. All were evaluated for stroke risk factors, had telemetry monitoring, transthoracic echocardiogram (TTE) and magnetic resonance angiography (MRA) of the head and neck. Transesophageal echocardiogram (TEE) was performed in three cases. Hyper-coagulable work-up was performed in one case. Trans-cranial Doppler was performed in one case.

RESULTS

Mean age was 73 years (range 55-88 years). Arm weakness in all patients was ranging from mild (-5/5) to moderate (2/5) and was predominantly distal (without plegia). None of the patients complained of limb pain or sensory deficit. Infarcts affected one gyrus (5/7) or, less often, 2 adjacent gyri (2/7), along the most distal aspect of the middle cerebral artery (MCA) territory. Risk factors included hypertension (6/7), diabetes (2/7), hyper-lipidemia (7/7), smoking (1/7) and prior TIA/stroke (3/7). The mechanisms of ischemic stroke were determined to be large artery atherosclerosis (2/5), cardioembolic (2/5), other determined etiology [hypoperfusion (1/5)] and undetermined etiology (2/5).

CONCLUSIONS

Our series of patients with small cortical infarcts and pure motor arm weakness show heterogeneous etiologies of stroke mechanisms and related long term outcomes. The risk factors appear to distribute as in most stroke populations, without a pattern specific to this unusual clinical presentation.

Isolated proximal leg paresis due to a small cortical infarction

We describe two patients with small cortical infarcts, who presented with isolated proximal weakness in one of their legs. These lesions were located in the contralateral precentral gyrus, more medial than the precentral knob, but more lateral than the topmost part of the motor cortex. These clinical findings are consistent with the physiological findings of Penfield and Boldrey, and those of recent activation studies by functional MRI. It is clinically important to pay close attention to the contralateral top of the motor cortex when examining pure motor monoparesis of a proximal part of a lower extremity.