The KickStrip: a novel testing device for periodic limb movement disorder.

STUDY

OBJECTIVES

In light of the ongoing debate over the clinical significance of periodic limb movement disorder (PLMD) and its monitoring in overnight sleep studies, we introduce a novel, portable, low-cost device for PLMD testing. The KickStrip is a disposable device, which includes a movement sensor, a central processing unit with real-time software, and a display. In the present study, the KickStrip final score (Kscore) is validated against the traditional periodic limb movement index (PLMI) based on overnight recordings in the sleep laboratory. DEISGN: Patients underwent full polysomnographic recordings concomitantly with the use of the KickStrip for a single night.

SETTING

Sleep Disorders Unit at Loewenstein Rehabilitation Hospital and Sleep Medicine Center at Rambam Medical Center, Israel.

PATIENTS: Eighty-two patients referred for overnight sleep recordings due to sleep disturbance of any kind.

INTERVENTIONS: N/A.

MEASUREMENTS AND

RESULTS

The Kscores were collected and the PLMI computed for each leg separately. Pearson correlations between Kscores and PLMI ranged between r = 0.83 to r = 0.88 (p < 0.001). Sensitivity and specificity values of the Kscores for increasing PLMD thresholds showed sensitivity ranging from 50% to 100% and specificity ranging from 83% to 100%. Receiver operating characteristic curves showed area-under-the-curve values ranging from 82% to 92%. Bland-Altman plot showed high agreement between the methods.

CONCLUSIONS

Comparisons between the Kscores and the traditional PLMI show increased accuracy with severity level and excellent agreement. The KickStrip is a valuable tool for PLMD testing for both clinical and research purposes.