Affiliation:
1. Department of Plastic and Hand Surgery, Inselspital
University Hospital Bern, Bern, Switzerland
2. Department of Surgery, Hand Surgery, Kantonsspital
Graubünden, Chur, Switzerland
Abstract
Abstract
Purpose Ultrasound (US) has gained in importance for the visualization of
morphological changes of injured nerves. After surgical repair, changes in
neural structures are seen over time. The correlation of morphologic changes in
US with the corresponding nerve function is uncertain. The aim of this study is
to determine a correlation of post-traumatic morphological nerve changes with US
and with nerve function after surgery.
Materials and Methods This dual-center, prospective cohort study was
conducted between 2017 and 2022 and included 20 mixed sensory motor nerve
lesions. Patients were followed up clinically (sensitivity, pain, and motor
function) with US and electroneuromyography. We determined the US changes of the
nerves including the interaction of the tissue after nerve repair and any
correlation with nerve function. With US nerve cross-sectional area (CSA), the
number of traversing fascicles, hypo-echogenicity, and presence of perineural
scar were analyzed.
Results 20 lesions (12 median and 8 ulnar nerves) of 18 patients with
intraoperatively confirmed nerve injury of at least 50% in the forearm were
included. The average CSA was over 20 mm2 throughout the follow-up
period, corresponding to a neuroma in continuity compared to the opposite side
(10.75 mm2). Sensibility and motor function at 12 months were
6xS3/4 and 10xM3-5. There was a statistically significant correlation between
continuous fascicles on US at 6 months and sensitivity at 12 months.
Conclusion This study supports the presence of post-traumatic
morphological changes in nerve fibers with US after traumatic injury.
Morphological changes in nerve structure after trauma can be detected with US
indicating a correlation between continuity of nerve fascicles and development
of sensitivity and motor function.