BACKGROUND: Peroneal neuropathy with an overt foot drop is a known risk factor for falling. Sub-clinical peroneal neuropathy (SCPN) due to compression at the fibular neck is subtler and does not have foot drop. A previous study found SCPN in 31% hospitalized patients. This was associated with having fallen. The purpose of this study is to determine the prevalence of SCPN in ambulatory adults and investigate if it is associated with falling.
METHODS: A cross-sectional study of 397 ambulatory adults presenting to outpatient clinics at a large academic hospital was conducted in 2016-2017. Patients were examined for dorsiflexion weakness and signs localizing peroneal nerve compression to the fibular neck. Fall risk was assessed with the Activities and Balance Confidence (ABC) Scale and self-reported history of falling. Multivariate logistic regression was used to correlate sub-clinical peroneal neuropathy with fall risk and a history of falls.
RESULTS: The mean age was 54 ± 15 years and 248 patients (62%) were female. Thirteen patients (3.3%) were found to have SCPN. After controlling for various factors known to increase fall risk, patients with SCPN were 3.74 times [95% confidence interval: 1.06 - 13.14] (p=0.04) more likely to report having fallen multiple times in the past year than patients without SCPN. Similarly, patients with SCPN were 7.22 times [95% confidence interval: 1.48 - 35.30] (p=0.02) more likely to have an elevated fall risk on the ABC fall risk scale.
CONCLUSIONS: Sub-clinical peroneal neuropathy affects 3.3% of adult outpatients and may predispose them to falling.