Skin temperature changes following sciatic nerve injury in rats.

Area of Science:

• Neuroscience
• Physiology
• Surgical Research

Background:

• Skin temperature is a clinically accessible indicator for assessing sympathetic dysfunction.
• Understanding peripheral nerve injury mechanisms is crucial for clinical management.
• Sciatic nerve injury models in rats allow for controlled investigation of neurophysiological changes.

Purpose of the Study:

• To track serial skin temperature changes in rat hindlimbs after different sciatic nerve injuries.
• To explore the underlying mechanisms influencing these temperature alterations.
• To correlate skin temperature with functional recovery and electrophysiological parameters.

Main Methods:

• Established three sciatic nerve injury models in Sprague-Dawley rats: complete transection and ligation (CTL), crush injury (CRI), and chronic constriction injury (CCI).
• Monitored serial skin temperature differences (ΔT) between intact and injured hindlimb areas.
• Evaluated sciatic functional index, sensory perception (hypoesthesia/hyperesthesia), and compound muscle action potential (CMAP) amplitude and latency.

Main Results:

• Skin temperature differences (ΔT) varied acutely across CTL, CRI, and CCI models.
• CCI model showed significantly higher ΔT in subacute to chronic stages (7-28 days) compared to CTL and CRI.
• Skin temperature changes (ΔT) were directly correlated with CMAP amplitude, indicating muscle functional status influences skin temperature post-injury.

Conclusions:

• Sciatic nerve injury significantly impacts hindlimb skin temperature, with patterns differing based on injury type.
• Skin temperature measurement can help differentiate between mild and moderate-to-severe peripheral nerve injuries.
• The functional status of the innervated muscle, reflected by CMAP, is a key determinant of post-injury skin temperature.