Why Chronic Subdural Hematomas Present with Gait Imbalances
Chronic subdural hematomas (CSDH) frequently present with gait disturbances because the slowly expanding mass compresses frontal motor regions and disrupts cortical-subcortical pathways controlling balance, motor planning, and coordination—symptoms that often mimic other neurodegenerative conditions and can delay diagnosis. 1
Pathophysiologic Mechanisms
The gait impairment in CSDH results from several interconnected mechanisms:
Mass effect on motor cortex and supplementary motor areas: The gradual accumulation of blood products creates compression of frontal and parietal regions responsible for motor control and spatial awareness, leading to impaired motor planning and execution 1
Disruption of cortical-subcortical circuits: CSDH compresses white matter tracts connecting cortical motor regions to basal ganglia and cerebellum, impairing the integration of motor commands with balance and postural reflexes 2
Cognitive-motor interference: The concurrent cognitive impairment (memory, attention, executive function) that accompanies CSDH creates a dual-task deficit where patients cannot simultaneously process cognitive demands and maintain stable gait 1, 3
Clinical Presentation Pattern
The triad of symptoms in CSDH creates a particularly high-risk scenario for falls:
Headache, altered consciousness, gait impairment, and hemiparesis are the most frequent presenting symptoms, with gait disturbance being particularly prominent in elderly patients 1
Cognitive decline co-occurs with motor deficits: Patients present with both focal neurological deficits and cognitive impairment, creating compounded risk for falls and injury 4
Insidious onset mimics other conditions: The gradual development over weeks to months means symptoms are often attributed to normal aging, stroke, or dementia rather than a surgically treatable lesion 5, 1
Differential Diagnosis Considerations
CSDH must be distinguished from other conditions causing gait disturbance in elderly patients:
Normal pressure hydrocephalus (NPH): Both present with gait disturbance and cognitive impairment, but NPH classically includes urinary incontinence and shows ventriculomegaly rather than extra-axial fluid collection 2
Vascular dementia: Can present with similar gait abnormalities, but imaging shows white matter changes and lacunar infarcts rather than subdural collections 2
Hepatic encephalopathy: May present with gait disturbances and altered consciousness, but subdural hematoma cases are commonly accompanied by focal neurological signs like hemiplegia that help differentiate them 2
Prognostic Implications
The presence of gait impairment has important implications for outcomes:
Balance and trunk control are significantly impaired: Studies show that even after successful surgical evacuation, patients require intensive rehabilitation focused on trunk control and standing balance to regain ambulatory function 3
Only 74.2% of previously ambulatory patients maintain gait function at discharge despite surgical treatment and rehabilitation, highlighting the severity of motor pathway disruption 3
Discharge disposition is affected: Only 45.7% of elderly patients with CSDH are discharged home, with residual gait and balance impairments being the primary factor preventing home discharge 3
Clinical Pitfalls
Several factors contribute to delayed recognition of CSDH as the cause of gait disturbance:
Symptoms overlap with common geriatric conditions: Headache, cognitive decline, and gait impairment are prevalent in multiple diseases affecting older adults, leading to misattribution 1
Lack of clear trauma history: Many patients do not recall a precipitating head injury, as the trauma may have been minor and occurred weeks to months prior 5, 1
Gradual progression masks urgency: Unlike acute subdural hematomas, the insidious nature of CSDH means patients and families adapt to slowly worsening function without recognizing the need for urgent evaluation 4