Table 2.
Timeline of functional motor recovery resulting from successful participation in the grasping and the staircase test and due to evocable compound muscle action potentials (CMAPs) recorded from the thenar muscle upon transcutaneous stimulation of the reconstructed median nerve
| Observation method | Group | 4 weeks | 8 weeks | 12 weeks |
|---|---|---|---|---|
| Paws/group (%) | Paws/group (%) | Paws/group (%) | ||
| Grasping testa | ANG | 1/16 (6.3%) | 14/16 (87.5%*) | 8/8 (100.0%) |
| MVG | 0/16 (0.0%) | 9/16 (56.3%) | 5/8 (62.5%) | |
| Staircase testb | ANG | 7/16 (43.8%*) | 15/16 (93.8%) | 8/8 (100.0%) |
| MVG | 1/14 (7.1%) | 11/14 (78.6%) | 6/8 (75.0%) | |
| Electrophysiological recordingsc | ANG | 12/16 (75.0%) | 16/16 (100.0%) | 8/8 (100.0%) |
| MVG | 14/16 (87.5%) | 15/16 (93.8%) | 8/8 (100.0%) |
ANG, autologous nerve graft; MVG, muscle‐in‐vein graft. Values are given both as exact numbers (left or right paws successfully participating per group) or as percentages (%). Earliest signs of functional motor recovery were found with the help of electrophysiological recordings while later on, the staircase test revealed an earlier onset of recovery of fine motor skills. Finally, reflex‐based grasping with a force representing most complete gross motor skills displayed the latest onset. Chi‐Square test was applied to examine significant differences between both groups (*p < .05 between ANG and MVG at the same time point). At 8 weeks postsurgery, the number of animals was reduced by 50% for interim histomorphometrical analysis.
As successful participation, only those paws were counted that were able to pull the grasping bar with a measurable force.
As successful participation, only those paws were counted that retrieved more than 3.0 pellets because we found that most animals were able to reach the first step with their tongue.
As successful outcome, only those paws were counted that revealed evocable CMAPs recorded from the thenar muscle.