Focal motor weakness and recovery following chronic subdural hematoma evacuation

The incidence of chronic subdural hematomas (cSDHs) is expected to climb precipitously in the coming decades because of the aging populous. Neurological weakness is one of the most common presenting neurological symptoms of cSDH. Yet, the recovery rates of motor strength recovery are seldom documented, as neurological outcomes have predominantly focused on broader functional assessment scores or mortality. In this study, the authors performed one of the first detailed analyses on functional motor weakness and recovery in patients who underwent cSDH evacuation.

Patients who underwent evacuation of a cSDH at a tertiary academic medical center between November 2013 and December 2021 were retrospectively identified using ICD-9 and ICD-10 billing codes. The presence of focal motor weakness was subcategorized by location as upper extremity (UE) or lower extremity (LE). Postoperative improvement, worsening, or resolution of weakness was recorded at the time of discharge. Statistical analysis included univariate and backward stepwise multivariable logistic regression modeling.

A total of 311 patients were included in the analysis. Patients were significantly more likely to experience UE weakness than LE weakness (29% vs 18%, p < 0.001). Forty-one percent (43/104) had both UE and LE weakness present. Risk factors for the development of focal motor weakness at the time of presentation were older age (OR 1.02, p = 0.03), increased cSDH size (OR 1.04, p = 0.02), and the presence of a unilateral cSDH (OR 2.32, p = 0.008). The majority of patients (68%, 71/104) experienced motor strength improvement following cSDH evacuation, with 58% (60/104) having complete resolution of weakness. Multivariable logistic regression analysis revealed that longer symptom duration was associated with lower rates of improvement (OR 0.96, p = 0.024). Older age was also associated with reduced resolution of weakness (OR 0.96, p = 0.02).

This study represents one of the first in-depth analyses investigating the rates of motor strength weakness and recovery following cSDH evacuation. Nearly two-thirds of all patients had complete resolution of their weakness by the time of discharge, and more than three-quarters had partial improvement. Risk factors for impaired neurological recovery were longer symptom duration prior to treatment and older age.