Reflexspannungen

Reflexspannungen, or reflex tensions, refer to involuntary muscle contractions that arise as part of the somatic reflex arc. When a muscle spindle detects stretch, sensory afferents relay the signal to the spinal cord, where it synapses with alpha motor neurons. The motor neurons send efferent impulses that cause the muscle to contract, counteracting the stretch. This stretch reflex is fundamental for maintaining posture, balance, and for protecting joints and tissues from overextension.

The most common examples of reflex tensions include the patellar (knee-jerk) reflex, ankle jerk, and the jaw jerk. Under normal circumstances, these reflexes are of short duration and moderate strength. However, in certain neurological or muscular conditions, reflex tensions can become hyperactive (hyperreflexia) or diminished (hyporeflexia). Hyperreflexia is often associated with upper motor neuron lesions, while hyporeflexia may indicate peripheral neuropathy or peripheral nerve damage.

Clinically, evaluation of reflex tensions is performed using a reflex hammer or handheld device. The amplitude and latency of the reflex contraction are recorded to detect abnormalities. Electrodiagnostic tests, such as electromyography and nerve conduction studies, can further elucidate the underlying cause of altered reflex tensions.

Management of abnormal reflex tensions depends on the underlying pathology. For hyperreflexia, antispasmodic medications (e.g., baclofen) or selective dorsal rhizotomy may be employed. In cases of hyporeflexia, addressing the peripheral nerve injury or supplementing with vitamin B12 and neurotrophic factors can aid recovery.

Research continues to explore the role of reflex tensions in motor learning, rehabilitation after injury, and in the development of age‑related sarcopenia.