History and Physical Examination
The diagnosis of restless legs syndrome (RLS) is based primarily on the patient’s clinical history. Often, patients do not bring RLS symptoms to the attention of the physician; accordingly, it can be helpful to include a few general sleep questions in the review of systems. RLS patients typically report dysesthetic sensations variously described as “pins and needles,” an “internal itch,” or a “creeping or crawling” sensation.
Approximately 85% of patients with RLS have periodic movements of sleep, usually involving the legs (periodic leg movements of sleep [PLMS]). [2] PLMS are characterized by involuntary, forceful dorsiflexion of the foot lasting 0.5-5 seconds and occurring every 20-40 seconds throughout sleep.
A large majority of patients (85%) with RLS report difficulty falling asleep at night as a consequence of the condition, and they may experience excessive daytime somnolence because of poor sleep quality resulting from multiple PLMS-induced arousals. PLMS noted on polysomnography (PSG) alone do not warrant treatment. Clinicians should consider treating PLMS if they are causing frequent arousals.
Other features commonly associated with RLS but not required for diagnosis include sleep disturbances, daytime fatigue, and involuntary, repetitive, periodic, jerking limb movements (either while the patient is asleep or while he or she is awake and at rest). A positive family history also aids in the diagnosis of RLS, especially in children.
RLS can be difficult to diagnose in children, especially younger ones. [22] For a definite diagnosis, patients must endorse the diagnostic criteria and be able to describe leg symptoms in their own language. [23] Alternatively, they must have the diagnostic criteria plus sleep disturbances, a sibling or parent with RLS, and a PLMS index higher than 5 on PSG. [22] For a possible diagnosis, a PLMS index higher than 5 on PSG and a first-degree family member with RLS are required. These strict criteria are intended to prevent overdiagnosis of RLS in children.
The physical examination is usually normal in patients with RLS; it is performed to identify secondary causes and to exclude other disorders. In particular, the patient should be evaluated for neuropathy, radiculopathy, and parkinsonism.
