Detection of Sub-Clinical Tarsal Tunnel Syndrome in Rheumatoid Arthritis Patients
Authors: Kandil Rehab S , Abdul Hakim Mervat M , Saber Nayera Z , El-Mallah Reem 
Published: July 2024

Abstract

Background
Asymptomatic or subclinical entrapments are common and frequent specially in patients with rheumatoid arthritis.

Objectives
Detection of sub clinical tarsal tunnel syndrome in rheumatoid arthritis patients and detect its correlation with disease activity and severity.

Patient and Methods
This case control was carried out on 16 patients with rheumatoid arthritis (RA) diagnosed according to American College of Rheumatology (ACR) and European League Against Rheumatism (EULAR) criteria of 2010 and 16 healthy controls matched for age and sex. Assessment of disease activity was done by Disease Activity Score in 28 joints (DAS28) and Rheumatoid Arthritis Severity Scale (RASS). Electrophysiological studies were conducted on a two channel EMG machine, for each patient on both legs.

Results
No significant differences were noted between study groups regarding basal demographic and clinical manifestations. In rheumatoid patient, mean ± SD for disease activity score (DAS) was 4.11±0.51 versus 2.51 ± 0.66 in control patient with p &lt; 0.0001. Regarding RASS, in rheumatoid patient, mean ± SD for disease activity was 28.94 ± 5.78; mean ± SD for functional impairment was 28.44 ± 5.46 and mean ± SD for physical damage was 31.75 ± 5.58 versus 11.44 ± 4.91, 13.88 ± 5.88 and 12.69 ± 4.24 in control group with statistically significant difference between both groups (p &lt; 0.0001). In rheumatoid cases, all patients (100%) were affected on medial plantar nerve “sensory latency and amplitude” of right and left sides, also, all patients (100%) were affected on lateral plantar nerve “sensory latency” of right and left sides, while for amplitude right and left; 31.25% of patients were affected. Medial plantar nerves (motor latency) in both sides weren‟t affected in any patients, while for amplitude and nerve conduction velocity the percentage of patients in right and left was 100%. Lateral plantar nerve (motor latency and amplitude) weren‟t affected in any patients in both sides, while for nerve conduction velocity the percentage of patients in right and left was 100%. Posterior tibial nerves (motor latency and nerve conduction velocity) weren‟t affected in any patients in both sides, while for amplitude the percentage of patients in right and left was 6.25%. No correlation was detected between DAS and RASS as regard clinical, laboratory data and electrophysiological study in rheumatoid cases. This was clearly demonstrated by sensitivity and specificity test that medial and lateral plantar nerved (sensory and motor) were of highly significant value and posterior tibial nerve (motor) was of insignificant value in detection of sub clinical tarsal tunnel syndrome in rheumatoid arthritis patients.

Conclusion
Subclinical entrapments and sub clinical tarsal tunnel syndrome were detected in all rheumatoid arthritis patients using electrophysiological study and they were positively correlated with disease activity and severity. Also, most of joint complaints of rheumatoid arthritis patients as oedema and pain were due undiagnosed subclinical entrapments and sub clinical tarsal tunnel syndrome.