The immediate effect of whole-body vibration therapy on mechanical nociceptive thresholds in horses with thoracolumbar pain.

Overview

• This study investigated the immediate effects of whole-body vibration therapy (WBV) on pain sensitivity in horses suffering from thoracolumbar (mid to lower back) pain.
• It aimed to measure the mechanical nociceptive thresholds (MNTs), which indicate pain sensitivity, before, immediately after, and 24 hours after a single session of WBV.

Introduction and Background

• Back pain in horses is difficult to manage and usually requires multiple treatment approaches.
• Whole-body vibration therapy (WBV) has been previously used in both horses and humans as a way to relieve pain and improve muscle strength.
• Previous research indicated that WBV could potentially worsen back pain if used long-term, but immediate effects after a session were not clearly studied.

Objective

• The study’s main goal was to determine how a single session of WBV affects mechanical nociceptive thresholds in horses with thoracolumbar pain.
• Mechanical nociceptive thresholds (MNTs) measure how much pressure or force causes pain, acting as an objective indicator of pain sensitivity.

Methods

• The study enrolled eight horses diagnosed with thoracolumbar pain and spinal pathology.
• Each horse received one 30-minute WBV session with the following parameters:
  • Frequency: 40 Hz
  • Amplitude: 0.8 mm
  • Acceleration: 4.9 m/s²
  • Vertical vibration
• MNTs were measured using pressure applied about 2 cm to each side of the midline at five anatomical locations:
  • Thoracic spine at vertebrae T13 and T18
  • Lumbar spine at vertebrae L3 and L6
  • Sacrum at vertebra S2
• Measurements were taken at three time points:
  • Before WBV treatment
  • Immediately after the 30-minute WBV session
  • 24 hours after WBV treatment

Results

• Immediately after the WBV session:
  • Mean MNTs were slightly higher (0.2 times increase), indicating a minimal and statistically insignificant change in pain sensitivity (P = 0.98).
  • This suggests almost no immediate pain relief or sensitivity change after one session.
• 24 hours after WBV:
  • Mean MNTs dropped by about two times compared to baseline, indicating a significant increase in pain sensitivity or worsening of pain (P < 0.0001).
  • This decrease was consistent regardless of the location of pain, the severity of back pathology, or the specific measurement site on the spine.

Conclusions

• WBV therapy showed no significant immediate pain relief effect on horses with thoracolumbar pain.
• More concerning, pain sensitivity significantly worsened 24 hours after a single WBV session, suggesting that short-term use might exacerbate back pain.
• The study advises caution in the short-term use of WBV for treating back pain in horses.
• Further research would be necessary to explore long-term effects, different WBV parameters, or combinations with other therapies.