Hand postures in primary and secondary generalized tonic-clonic seizures

To evaluate and identify the frequency of hand postures during generalized convulsions in patients with genetic generalized epilepsy (GGE), localization-related epilepsy (LRE), and nonepileptic attacks (NEA).

We retrospectively analyzed 98 consecutive videos of generalized convulsions in 62 patients who were admitted for diagnostic video-EEG monitoring. Demographics were recorded, and hand postures were subdivided into fanning, fisting, index-finger pointing (IFP), clawing, and flaccid posturing. Hand postures were then compared between patients with GGE, LRE, and NEA for each stage of the convulsion and for the whole event.

In patients with LRE, 96% had IFP, where fanning occurred in 91.3% of GGE (and only at onset), and the flaccid hand posture occurred in 56.0% of NEA. Fisting, fanning, and IFP postures all occurred significantly more frequently during epileptic seizures than during NEA (74.0% vs 32.0%, p = 0.0003; 60.3% vs 20.0%, p = 0.0005; 83.6% vs 12.0%, p < 0.0001). The claw hand posture was present only during NEA, and the flaccid posture occurred significantly more frequently during NEA than during epileptic seizures (56.0% vs 15.1%, p = 0.0001).

Distinct ictal hand or finger posturing is present in patients with GGE, LRE, and NEA. The presence of any fisting, fanning, clawing, IFP, or flaccid hand posturing can help distinguish epileptic seizures from NEA. IFP suggests LRE while fanning with evolution suggests GGE. Overall, hand posturing during seizures provides unique information and aids in the differential diagnosis and classification of epilepsy.