Pulsed Electromagnetic Fields Accelerate Sensorimotor Recovery Following Experimental Disc Herniation

Spine (Phila Pa 1976). 2021 Feb 15;46(4):E222-E233. doi: 10.1097/BRS.0000000000003762.


Study design: An experimental animal study.

Objective: The aim of this study was to investigate the effect of pulsed electromagnetic fields (PEMF) on recovery of sensorimotor function in a rodent model of disc herniation (DH).

Summary of background data: Radiculopathy associated with DH is mediated by proinflammatory cytokines. Although we have demonstrated the anti-inflammatory effects of PEMF on various tissues, we have not investigated the potential therapeutic effect of PEMF on radiculopathy resulting from DH.

Methods: Nineteen rats were divided into three groups: positive control (PC; left L4 nerve ligation) (n = 6), DH alone (DH; exposure of left L4 dorsal root ganglion [DRG] to harvested nucleus pulposus and DRG displacement) (n = 6), and DH + PEMF (n = 7). Rodents from the DH + PEMF group were exposed to PEMF immediately postoperatively and for 3 hours/day until the end of the study. Sensory function was assessed via paw withdrawal thresholds to non-noxious stimuli preoperatively and 1 and 3 days postoperatively, and every 7 days thereafter until 7 weeks after surgery. Motor function was assessed via DigiGait treadmill analysis preoperatively and weekly starting 7 days following surgery until 7 weeks following surgery.

Results: All groups demonstrated marked increases in the left hindlimb response threshold postoperatively. However, 1 week following surgery, there was a significant effect of condition on left hindlimb withdrawal thresholds (one-way analysis of variance: F = 3.82, df = 2, P = 0.044) where a more rapid recovery to baseline threshold was evident for DH + PEMF compared to PC and DH alone. All groups demonstrated gait disturbance postoperatively. However, DH + PEMF rodents were able to regain baseline gait speeds before DH and PC rodents. When comparing gait parameters, DH + PEMF showed consistently less impairment postoperatively suggesting that PEMF treatment was associated with less severe gait disturbance.

Conclusion: These data demonstrate that PEMF accelerates sensorimotor recovery in a rodent model of DH, suggesting that PEMF may be reasonable to evaluate for the clinical management of patients with herniation-associated radiculopathy.Level of Evidence: N/A.

MeSH terms

  • Animals
  • Cytokines
  • Ganglia, Spinal / physiopathology
  • Ganglia, Spinal / radiation effects
  • Intervertebral Disc Degeneration
  • Intervertebral Disc Displacement / complications
  • Intervertebral Disc Displacement / physiopathology*
  • Intervertebral Disc Displacement / radiotherapy*
  • Male
  • Radiculopathy / etiology
  • Radiculopathy / physiopathology
  • Radiculopathy / radiotherapy
  • Rats
  • Rats, Sprague-Dawley
  • Walking Speed / radiation effects


  • Cytokines

Supplementary concepts

  • Intervertebral disc disease