ABSTRACT
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) (nâ=â6), DH alone (DH; exposure of left L4 dorsal root ganglion [DRG] to harvested nucleus pulposus and DRG displacement) (nâ=â6), and DHâ+âPEMF (nâ=â7). Rodents from the DHâ+âPEMF group were exposed to PEMF immediately postoperatively and for 3âhours/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: Fâ=â3.82, dfâ=â2, Pâ=â0.044) where a more rapid recovery to baseline threshold was evident for DHâ+âPEMF compared to PC and DH alone. All groups demonstrated gait disturbance postoperatively. However, DHâ+âPEMF rodents were able to regain baseline gait speeds before DH and PC rodents. When comparing gait parameters, DHâ+âPEMF 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.