New clinical characteristics and risk factors of hand knob infarction

Hand knob infarction (HKI) is a rare clinical condition which is often misdiagnosed as peripheral neuropathy. This study aimed to identify the clinical characteristics and risk factors of HKI. Nine HKI patients admitted between January 2013 and March 2016 were confirmed by magnetic resonance imaging. Their medical records were collected and analyzed. The modified Rankin Scale was used to assess clinical outcomes. Routine laboratory tests, electrocardiogram, echocardiography, cranial magnetic resonance imaging, magnetic resonance angiography, computed tomography angiography, and Doppler ultrasonography examinations were performed. Seven patients had uniform involvement of all digits. One patient with radial weakness had a lesion in the lateral area of hand knob, and another patient with ulnar weakness had a lesion distributed in the medial area of hand knob. Hyperhomocysteinemia was a most common risk factor for HKI. Most HKI patients had a benign disease course, but three patients (33.33%) with the stroke type of large artery atherosclerosis had disease recurrence. We characterized clinical characteristics and risk factors of HKI which will help the diagnosis and management of HKI.