Diffusion tensor imaging of the median nerve healing. Preliminary results.

AIMS: This study aimed to examine the correlation between DTI, clinical assessment, and electromyography results in patients who underwent primary median nerve repair.

METHODS

Ten patients who underwent primary repair of the complete median nerve transection were included. Study assessments were performed on both the traumatized and non-traumatized extremities and patients were followed up for a minimum duration of 11 months. Clinical assessments, (Tinnel test, static 2-point discrimination test, motor and quality of life assessments), electromyography and DTI were performed.

RESULTS

None of the clinical or electromyographic parameters correlated significantly with any of the diffusion tensor imaging parameters, i.e. fractional anisotropy (FA) or apparent diffusion coefficient (ADC) (p>0.05 for all). In addition, The Disabilities of the Arm, Shoulder and Hand (DASH) scores did not correlate with either FA (r=0.55, p=0.098) or ADC (r=0.40, p=0.260) values. However, Tinnel positive cases (n=3) had lower relative FA when compared to Tinnel negative cases (n=7) (-0.11±0.19 vs. 0.05±0.04, p=0.033).

CONCLUSION

Our findings do not support the presence of relations between DTI parameters and electromyographic or most of the clinical parameters. Further MRI studies with larger numbers of patients with complete transection of the median nerve using the novel imaging parameters are warranted.

KEY WORDS: Diffusion Tensor Imaging (DTI), Electromyography (EMG), Median nerve, Nerve injury, Nerve repair.