Fahr's Syndrome

Original Editor - Sarah Dorsey, Maria Tyumkin, Megan Willerth, Jennifer Withers, Logan Wood.

Lead Editors  

Clinically Relevant Anatomy

Definition: Fahr’s syndrome has several different names that it goes by including Fahr’s disease and familial idiopathic basal ganglia calcification. Fahr’s syndrome is a rare neurological disorder characterized by bilateral symmetric calcification's of the areas in the brain responsible for movement including: the basal ganglia most commonly the globus pallidus, the cerebellum most commonly the dentate nucleus, the thalamus, the hippocampus, and the cerebral cortex. The calcifications are hypothesized to be due to lipid deposition and demyelination. The presentation of a patient with Fahr’s disease can vary greatly with some individuals remaining asymptomatic. In more severe cases individuals will present first and most prominently with extrapyramidal symptoms, Further symptoms may include: progressive psychosis, cognitive impairment, dementia, gait disturbance, and sensory changes. Fahr’s syndrome can present at age, but is typically seen in individuals between the ages of 40-60 years old.

Pathological Process/Prognosis

Etiology:  Fahr's syndrome is familial and inherited in an autosomal dominant fashion, making up 60% of the diagnosed cases. Some research has shown that fewer cases may be inherited in an autosomal recessive fashion. When Fahr’s syndrome is inherited the causes of the calcification in the brain are idiopathic. There are also several other factors that could lead to Fahrs syndrome besides genetics, which include: endocrinopathies, vasculitis, mitochondrial disorders, infections, other inherited disorders, radiation, chemotherapy, carbon monoxide poisoning.

Prognosis: The prognosis of Fahr’s syndrome differs from person to person and thus is hard to predict. Fahr’s syndrome is a progressive disease with no known cure and no specific treatments at this time. Due to Fahr’s progressive and degenerative features individuals will often lose previously acquired skills and motor control, which can lead to death. It is interesting to note that there is no direct correlation between the amount of calcium deposits that are seen in the brain, and the degree of neurological impairments shown by an individual with the disease.

Clinical Presentation

Lesions in the basal ganglia can cause patients to present with different motor deficits. These include slowness of movement, involuntary extra movement and alterations in posture and muscle tone. Therefore patients with basal ganglia involvement can present on a continuum of motor behaviour from severely limited as seen in the final stages of Parkinson’s disease to excessive movements apparent in Huntington’s disease.  In “Fahr’s Disease Registry”, the most common symptoms were movement disorders, in particular parkinsonism, which affects more than half of patients.

Associated Movement Disorders

Dystonia: is a movement disorder that causes sustained muscle contractions, abnormal postures and repetitive twisting movements that can vary in speed. Dystonia can affect one or several regions of the body. There is presently no cure for dystonia, but the goal is to help decrease the severity of muscle spasms, pain and awkward postures to improve overall quality of life.

Athetosis: involuntary movement disorder characterised by slow, smooth, sinuous, writhing movements, also described as “wormlike movements”. More common in the distal upper extremities, also prevalent in other areas of the body such as face, trunk, neck and tongue. Pure Athetosis is uncommon, usually presents with a combination of spasticity, tonic spasms, or chorea.

Chorea: described as abnormal movement involving involuntary, irregular, purposeless, non-rhythmic, abrupt, rapid and unsustained, that can flow from one area of the body to another. These movements can vary in amplitude, small movements of the fingers to flailing of limb movements, referred to as ballism. Patients are at an increased falls risk due to impairments in balance, strength and increased fatigue. Musculoskeletal and respiratory changes can result in physical deconditioning and contribute to decreased participation in daily activities and social participation.

Spasticity: motor disorder characterized by a velocity dependent increase in muscle tone with increased resistance to stretch, the larger and quicker the stretch, the stronger the resistance of the spastic muscle. During the rapid movement, a sudden inhibition or letting go of the limb termed the “clasp knife” response may follow initial high resistance.

Chronic spasticity is associated with contracture, abnormal posturing and deformity, muscle weakness, functional limitations and disability.

Tremor: is an involuntary shaking movement.  It can be seen in the extremities, usually as a resting tremor seen when a patient is at rest, or in the head and trunk when the patient is trying to hold an upright posture.  A resting tremor can eventually progress to an action tremor, which is tremor with movement. Although the pathophysiology is slightly different, Parkinson’s patients tend to exhibit a mild tremor first on only one side of the body; there is not enough data to decisively say if this it true for Fahr’s patients.  Tremors tend to worsen with stress, anxiety or an excited emotional state. Particularly in later stages, tremors interfere with the ability to perform fine motor tasks such as picking up or holding objects.

Rigidity: is an increased resistance to passive movement that is not affected by speed or amplitude of motion.  There are two types: lead pipe - which is constant throughout range - and cogwheel - which is jerky with tension felt intermittently throughout a movement.  Rigidity affects a patient’s ability to move and therefore independently carry out activities of daily living (ADLs). In many patients, rigidity can be increased by stress or active movements.

Hypomimia: is the reduced ability to portray facial expressions, both automatic and voluntary, that is often seen in Parksinon’s and Fahr’s patients.  This frozen, masked expression is often incorrectly interpreted by others as depression, coldness, apathy and reduced cognition. This can cause difficulty in communication and relationships, including patient-therapist relationships; studies have shown that practitioners - including physiotherapists - tend to view patients with facial masking as more depressed, less sociable and less cognitively competent.  Therefore it is an important component of the treatment of Fahr’s disease to not allow oneself to form negative preconceptions about a client based on a symptom they cannot control.

Gait: is affected by Fare’s disease similar to Parkinson’s disease.  Fare’s patients can exhibit unsteadiness, clumsiness, a shuffling gait, or freezing of gait.  Gait abnormalities can be exacerbated by other symptoms such as tremor or rigidity (O’sullivan Rehabilitation text).

Diagnostic Procedures

add text here relating to diagnostic tests for the condition

Differential Diagnosis

add text here relating to the differential diagnosis of this condition

Assessment and Outcome Measures

add links to outcome measures here (see Outcome Measures Database)

Medical Management

add text here relating to management approaches to the condition

Physiotherapy Intervention

add text here relating to physiotherapy treatments

Resources for Patients

add appropriate resources here