Nerve conduction study and gastrocnemius H reflex response in rheumatoid arthritis

We aimed to evaluate nerve conduction studies and gastrocnemius H reflex responses in rheumatoid arthritis (RA) patients and compared to the healthy adult subjects.

Twenty-six RA patients and twenty-two healthy adult subjects were included in the study. The nerve conduction study (NCS) findings and bilateral gastrocnemius H reflex responses were evaluated in all the groups. Age, gender, subcutaneous nodules, joint deformities, laboratory parameters, duration of disease, anti-rheumatic drug and steroid usage were recorded. Activity of disease was assessed using a 28-joint disease activity score (DAS28).The functional status was measured using the health assessment questionnaire (HAQ), pain intensity measured using a visual analog scale (VAS).

The rate of electroneuromyographic (ENMG) abnormalities was 73% in RA patients. The most common diagnosis was carpal tunnel syndrome (61.4%). There were no significant correlations between ENMG findings and clinical and laboratory features evaluated. Right H reflex latencies were statistically longer in RA patients (p=0.03). According to calculated cut-off levels, there were more subjects with longer H reflex latencies in RA patients.

In this study, entrapment neuropathies were found common as independent identity from duration and severity of disease in RA patients. For H reflex latencies, cut-off values were longer in RA patients. It may provide information about the early neuropathic involvement of long peripheral nerves in RA patients. But this findings are needed to be supported by larger population study.