Aim: The aim of the study was to assess the cellular and structural properties of skeletal muscle in Restless legs Syndrome (RLS).
Method: Twenty patients and 16 controls were included. Aerobic performance was assessed using a sub maximal test. On muscle biopsies taken from the tiabialis anterior, fibre distribution and fibre area were analysed together with parameters surveying the microvascularisation, especially the tortuosity which is expressed as a percent of muscle fibre perimeter in contact with the wall of the microvessel, LC/PF-index (length of capillary / perimeter of fibre).
Result: RLS group had significantly lower predicted maximal oxygen uptake (p = 0.01) and significantly higher LC/PF index (P=0.01) compared to the controls. In conclusion, the higher capillary tortuosity in RLS patients indicates the occurrence of significant remodelling in capillary geometry in RLS.