Actigraphy for Periodic Limb Movements in Sleep
Periodic Limb Movements in Sleep (PLMS) as well as being a sleep disorder in its own right is also a manifestation of Restless Legs Syndrome (RLS) and can be a symptom either of Parkinson’s disease and other disorders of the central nervous system or can even be the result of drug administration.
Using our specialized software and MotionWatch devices mounted across the toes of the subject, it is possible to detect the occurrence of PLMS and measure its severity.
Overnight recordings can be made to screen for PLMS for up to 6 consecutive nights at a 1 second resolution. The key advantage is that the subjects can wear the devices in their own homes without the need for admission to a sleep clinic.
The frequency and duration of kicks can be automatically classified as bouts of PLMS and the analysis conforms to the ICSD-2 or ICSD-3 specifications. The activity for each leg is displayed graphically and information is provided about the PLMS amplitude, duration and periodicity for individual legs as well as for both legs combined. The analysis is based upon scientific research and validation of actigraphy for PLMS.
The intuitive graphical user interface allows rapid analysis of specific periods of interest with the option to manually exclude unwanted movements or bouts.
The PLMS Analysis functions with standard MotionWatch 8 devices which offers excellent flexibility in terms of equipment ownership costs.
It should be noted that Actigraphy for PLMS is not intended as a replacement for EMG in a sleep lab, but is a valuable tool in gaining insights into the need for the clinical investigation of PLMS.
The PLMS software includes the option for a ‘Suggested Immobilization Test’ (SIT) to aid with diagnosis of RLS in the period of wake before bed time. Set up independent analysis periods to capture motor activity and the movement data are scored automatically as PLMW (Periodic Limb Movement during Wakefulness).
Worn in home environment
6 nights recording @ 1s epoch
Auto PLMS classification
ICSD 2/3 compliant
Cost effective screening tool
RLS detection with SIT function
Detection of PLMS
CNS disorder research
Set-up for Analysis
The PLMS software provides a visualisation of the physical activity, individual ‘kicks’, PLMS bouts, PLMS duration and PLMS periodicity. Both left, right and combined limb data are displayed when loaded. Data can be manually included or excluded as PLMS. The screenshot below shows an example of the analysis window:
The PLMS software provides a results summary for each limb for each night. The report may be printed with options to select the included stats and/or graphs. The full results may also be copied to the clipboard or be saved to a text file. The screenshot below shows an example of the results for combined (merged) for day 1 of the analysis:
References and Validation
The PLMS analysis is based upon research and validation of the application of actigraphy in the detection of PLMS.
One MotionWatch 8 is required for each limb to be monitored. The MotionWatch is a small, light-weight and fully waterproof actigraph providing key endpoints for sleep, chronobiology and physical activity. The MotionWatch 8 is quickly detached from its standard wrist mounting and re-attached to the PLMS foot strap.
The PLMS foot mounting strap is an adjustable, elasticated strap that provides a comfortable method for wearing the MotionWatch 8 near the toes of the limb to be monitored. The MotionWatch 8 is quickly detached from its standard wrist mounting and re-attached to the PLMS foot strap.