Documentation of brachial plexus compression in the thoracic inlet with quantitative sensory testing

Area of Science:

• Neurology
• Orthopedics
• Sensory Physiology

Background:

• Thoracic outlet syndrome (TOS) involves compression of the brachial plexus in the thoracic inlet.
• Accurate diagnosis of TOS can be challenging, necessitating reliable diagnostic tools.
• Evaluating sensory nerve function is crucial for understanding TOS pathophysiology.

Purpose of the Study:

• To assess the utility of the Pressure-Specifying Sensory Device (PSSD) in quantifying cutaneous pressure thresholds.
• To differentiate between individuals with and without TOS based on sensory testing.
• To determine if provocative maneuvers alter sensory perception in TOS patients.

Main Methods:

• A cohort of 61 controls and 11 TOS patients were evaluated by upper-extremity specialists.
• The PSSD was used to measure the one-point cutaneous pressure threshold on the index and little fingers.
• Measurements were taken in both unprovoked (adducted) and provoked (180-degree abducted) arm positions.

Main Results:

• Control subjects exhibited no significant change in pressure thresholds between positions.
• TOS patients demonstrated a significant increase in pressure thresholds in both positions (p < .0001).
• TOS patients consistently had higher pressure thresholds than controls in both tested positions (p < .0001).

Conclusions:

• Changes in cutaneous pressure threshold, measured by PSSD, can effectively identify patients with symptomatic brachial plexus compression.
• Provocative testing of the brachial plexus in conjunction with PSSD measurements offers a valuable diagnostic approach for TOS.
• This sensory testing method provides objective data for TOS diagnosis.