Table 1.

Magnitude of responses to mechanical stimulation of the lesion site in axotomized cutaneous nerve fibers

Fibers n (A, C)Tests n (A, C)Impulses/30 sec evoked by consecutive trains of von Frey hair stimuli
(1) Stimulus train median; rangeTreatment(2) Stimulus train median; rangeTreatment(3) Stimulus train median; range
I29  (19, 10)42  (28, 14)23.0; 2–24421.0; 1–295*
II8  (5, 3)13  (8, 5)40.0; 6–98Contr. sol.35.0; 2–113*
III40  (24, 16)40  (24, 16)9.0; 2–244IS21.0; 2–337**
IV5  (2, 3)10  (4, 6)29.0; 0–68Contr. sol.21.5; 0–64*IS48.0;  4–98**
  • Consecutive trains of von Frey stimuli were applied within 10 min. Treatment between two trains: I, none; II, 2 min application of control solution (Contr. sol.); III, 2 min application of inflammatory soup (IS); IV, application of control solution between (1) and (2) stimulus train followed by IS application between (2) and (3) stimulus train. Some A and C fibers were tested twice with two consecutive trains using two different von Frey hairs. 11/19 A and 6/10 C fibers listed under I were additionally exposed to IS. These fibers and the corresponding responses are therefore also included in III. The remaining eight A and four C fibers of I were either exclusively mechanically stimulated without any treatment between two stimulus trains (3 A, 1 C) or additionally received control solution between two trains (5 A, 3 C). The responses of the latter fibers induced before and after application of control solution are given under II. A subgroup (2/5 A, 3/3 C) of the latter were tested further by IS; results are given under IV. Wilcoxon matched-pairs test; *p > 0.15; **p < 0.005.