The pressor sign refers to an exacerbation of pre-existing pain with an increase in intrathoracic or intra-abdominal pressure, typically triggered by coughing, sneezing, or straining. In clinical practice, it is primarily considered an indication of space-occupying pathology within the spinal canal. In neurosurgery, the pressor sign is of particular importance in the diagnosis of herniated discs[^1].
Pathophysiology
The underlying pathophysiology of the pressor sign is based on the Valsalva maneuver. Forced expiration against a closed glottis leads to an increase in intrathoracic and intra-abdominal pressure. This pressure is transmitted to the epidural space and results in a transient increase in pressure within the spinal canal.
If pre-existing narrowing of the Spinal canal or a Nerve root is present, the additional increase in pressure may cause a transient exacerbation of nerve root compression. Clinically, this manifests as an acute exacerbation of radicular or localized pain.
Clinical relevance
The pressor sign is a classic clinical symptom indicating pressure-sensitive pathology in the region of the Spine . In neurosurgery, it serves as an important clinical indication of herniated discs and other space-occupying processes, but it does not replace diagnostic imaging. Its strength lies in its ease of elicitation and its value for clinical orientation as part of the neurological examination.