Assistant Professor of Physical Medicine and Rehabilitation Mayo Clinic Rochester, Minnesota, United States
Case Diagnosis: Hand-Knob Stroke
Case Description: A healthy 42 y.o. male presented to an ED with acute symptoms of dominant right hand and wrist weakness and paresthesias. While NIH stroke scale was 0, physical exam showed weakness of the right wrist, fingers, and intrinsic hand muscles. Initial diagnosis was peripheral neuropathy (PN) with plan for outpatient EMG, however given lack of PN risk factors and acute symptom onset, brain imaging was obtained. It demonstrated a hypodense lesion in the left postcentral gyrus, within the hand-knob territory. Comprehensive stroke evaluation was unremarkable with the exception of echocardiogram showing a large patent foramen ovale (PFO).
He was treated pharmacologically and with PFO closure. He completed outpatient occupational therapy. Upon follow up in physiatry clinic three months post-stroke, his symptoms were improved, and he was able to return to full-time work without restrictions.
Discussions: Physiatrists evaluating patients with symptoms suggesting peripheral nerve etiologies should consider hand-knob stroke, especially in younger, previously healthy adult patients with no risk factors for peripheral nerve disease.
Classically, the ‘hand knob area” resides in the precentral gyrus, with 90% of lesions taking the form of an inverted Omega on radiographic imaging. Lesions in the postcentral gyrus are also common.
Although rare, hand knob strokes are well-defined stroke entities, most likely of embolic etiology. While atherosclerosis and hypertension are prevalent risk factors, PFOs or thrombophilia are described underlying mechanisms. If diagnosed, treatment involves interventions aimed at stroke prevention and occupational therapy to promote recovery and reduce disability.
Conclusions: A hand-knob stroke should be in the differential when evaluating patients presenting with isolated, unilateral hand/forearm neurologic changes. Early and accurate identification of stroke directs treatment and rehabilitation interventions accordingly.
.jpg "Erica Bellamkonda, MD photo")
