Abstract
Background We explore a minimally invasive method (combined ultrasound detection, electrode
placement and electrophysiologic nerve examination) to evaluate the early-stage quality
of a nerve suture site.
Methods Ten patients with median and/or ulnar nerve injuries who had undergone nerve suture
were recruited. Postoperative ultrasound examination found that the nerve injury was
sutured. Then, a stimulating electrode and recording electrode were located beside
the nerve proximal and distal to the suture site guided by ultrasound. Measurement
of nerve action potentials (NAP) were performed with these electrodes, followed by
surgical exploration. The pre- and intraoperative electrophysiologic findings were
compared, together with amplitude, latency, and wave shape of NAP.
Results Of the 10 patients, 3 patients were diagnosed with median nerve injury, 2 with ulnar
nerve injury, and 5 with the median nerve and ulnar nerve injury. NAP could not be
detected pre- and intraoperatively in three median nerves from three patients and
in two ulnar nerves from two patients. NAP was detected in 10 nerves from the remaining
5 patients. The pre- and intraoperative NAP results showed consistent results concerning
the status of the nerve suture. Wilcoxon's signed-rank test indicated no significant
difference in the amplitude and latency detected via sonographically placed electrodes
and during surgical exploration. The number of negative-phase waves were equally distributed.
Conclusion Ultrasound-guided electrode placement and NAP detection can substitute surgery and
serve as a minimally invasive approach to evaluate the regeneration of a sutured nerve.
Keywords
peripheral nerve injury - ultrasound - nerve action potential - electrophysiologic
detection
