Phenotypes and Electrophysiological Features of Hereditary Neuropathy with Liability to Pressure Palsies (HNPP) According to Physical Activities: A Single Military Hospital Experience

Abstract

AbstractBackgroundThe typical symptom of HNPP is focal nerve palsy with complete or near complete recovery, and it often occurs during military service with upper extremity weakness due to a brachial plexus involvement. This study aimed to analyze the clinical features and neurophysiological examination results of HNPP occurring in the Korean military to determine whether the clinical presentations and electrodiagnostic patterns differ according to the trigger activity and to obtain useful information for the early diagnosis of HNPP.MethodsSixty-four patients with HNPP were included over an 11-year period, and medical records and electrophysiological tests were analyzed.ResultsThirty-five patients presented with isolated compressive neuropathy and 18 patients presented with brachial plexopathy. Analysis of phenotypes according to triggering activity revealed that 13 of 16 patients with symptom onset after military training showed a type of isolated compressive neuropathy and that 11 of 20 patients with symptom onset after push-ups or after backpack carriages showed a type of brachial plexopathy. Six patients experienced symptoms following sleep, while four reported symptoms after trauma. Atypical features were observed in 11 cases (17.2%), including 3 lower lumbosacral radiculopathy-like presentation. Abnormal findings were observed in 91.2% of distal latency of the peroneal motor nerve.ConclusionsThe phenotype varied according to the physical activity that triggered HNPP onset in soldiers. These results are expected to help in the early diagnosis of HNPP in soldiers or those who develop it after physical activity.key messagesThis study underscores the importance of recognizing clinical manifestation of HNPP in military personnel, particularly those involved in physically demanding activities, to facilitate timely diagnosis and intervention.The phenotypes of HNPP in soldiers vary depending on the triggering activity, with isolated compressive neuropathy and brachial plexopathy being the most common presentations.Atypical clinical manifestations were observed, including presentations resembling Guillain–Barré syndrome and lumbosacral radiculopathy.Regardless of the location of symptoms, a peroneal motor conduction study can be valuable in diagnosing HNPP.These findings could significantly contribute to the early diagnosis of HNPP in soldiers.