Subacute Combined Degeneration

Subacute Combined Degeneration is a condition that affects the spinal cord, specifically damaging the nerves responsible for movement and sensation. It is caused by a deficiency of vitamin B12, which is essential for maintaining healthy nerve cells. This damage leads to symptoms such as weakness, difficulty walking, and problems with balance and coordination. The condition primarily affects the posterior and lateral columns of the spinal cord, which are important for transmitting sensory and motor signals. If untreated, it can cause permanent nerve damage and disability. Early recognition and treatment are crucial to prevent progression.

Subacute Combined Degeneration (SCD) is a neurological disorder characterized by demyelination of the posterior (dorsal) columns and lateral corticospinal tracts of the spinal cord. It is most commonly caused by vitamin B12 deficiency, which impairs myelin synthesis due to disrupted methylation and accumulation of toxic metabolites. The condition leads to combined sensory ataxia from dorsal column involvement and upper motor neuron signs from corticospinal tract damage. Clinically, patients present with paresthesias, gait ataxia, and spastic paresis. SCD is a major cause of subacute myelopathy and is often associated with pernicious anemia or malabsorption syndromes. Early diagnosis and treatment with vitamin B12 supplementation can halt progression and partially reverse symptoms.