Thermal stimulus elicits post-neurotomy pain.
(A) Hollow circles indicate the summed behavioral response score for each animal for both TNT (red) and SHAM (grey) groups. Statistically significant mean pain response scores (solid black line) were observed between TNT and SHAM groups in week 4 and in weeks 6–8, following bulb resection (B). Lidocaine was found to be a successful moderator of heat-induced neuroma pain. Dashed black lines indicate population median. (B) Following bulb resection surgery, significant heat-induced neuroma pain persisted from week 6 until week 28. No statistically significant difference was found between animals receiving bulb resections vs TNT-SHAM animals. For statistical comparisons between groups, a two-tailed Mann-Whitney test was used (* p<0.05, ** p<0.01). (C) Thermal stimulus exposure induces a significant mean skin temperature increase. A mean skin temperature increase of approximately 5°C was observed following 5 minutes of heat-lamp exposure. (D) Recovery-to-Stimulus behavioral response ratios for all time points.