Introduction. Recent studies suggested that the progression of osteoarthritis (OA), a chronic degenerative joint disease, may be affected by the autonomic nervous system (ANS). Under healthy conditions, the sympathetic (SNS) and parasympathetic (PNS) branches of the ANS are well coordinated to maintain homeostasis. However, pathological conditions are frequently associated with a disturbance of this fine-tuned balance. Therefore, we analyzed whether an autonomic dysfunction occurs in OA patients. Method. 225 participants with early- or late-stage knee OA as well as 40 healthy age-matched probands were included in this study. Autonomic activity was investigated by analyzing heart rate variability (HRV), which decreases under chronic sympathetic overactivity. Time- and frequency-domain HRV indices SDRR, RMSSD, pRR50 and LF were examined. Linear regression analysis was performed to adjust for clinical characteristics, such as age, sex, BMI, or medication. Moreover, perceived chronic stress (PSQ) and pain (WOMAC) were assessed via questionnaires. In addition, the serum stress hormones cortisol, DHEA-S and IL-6 were analyzed via ELISA. Result. SDRR, RMSSD, and pRR50 were slightly reduced in the early stage of OA and showed significant decrease in the later stage of the disease. Also LF decreased significantly with OA progression. HRV was significantly influenced by the grade of OA, but not other patient characteristics. Moreover, late-stage OA patients demonstrated significantly higher PSQ and WOMAC levels compared to healthy controls. In addition, cortisol/DHEA-S ratio and IL-6 serum concentrations were significantly higher in late-stage than in early-stage OA patients and healthy controls. Conclusion. Reduced HRV, increased cortisol/DHEA-S ratio and PSQ level as well as elevated systemic IL-6 concentration indicated an autonomic shift towards a more pronounced SNS activity due to PNS deficiency in OA patients, particularly in the late-stage of the disease. Therefore, modulation of the ANS, for example by vagus nerve stimulation, might be a potential treatment strategy for of knee OA patients

Osteoarthritis (OA) is the most common degenerative joint disorder. Its multifactorial etiology includes age, sex, joint overloading, genetic or nervous influences. In particular, the autonomic nervous system is increasingly gaining in importance. Its two branches, the sympathetic (SNS) and parasympathetic nervous system, are well-balanced under healthy conditions. OA patients seem to be prone to an autonomic imbalance and therefore, we analyzed their autonomic status. More than 200 participants including patients with early and late stage knee OA (before and 1 year after knee replacement surgery) and healthy probands (age-matched) were analyzed. Heart rate variability was measured via electrocardiogram to assess long-term sympathetic (low-frequency=LF) and parasympathetic (high-frequency=HF, pRR50) activities or general variability (RMSSD, SDRR). Serum cortisol concentrations were measured by ELISA. Perceived chronic stress (PSQ) was assessed via questionnaire. Multivariant regression was performed for data analysis. LF/HF value of early OA was slightly increased compared to healthy controls but significantly higher compared to late OA patients before (p>0.05) and after TKR (p>0.01). HF in late OA patients before TKR was significantly decreased compared to patients after TKR (p>0.001) or healthy controls (p>0.05). Healthy probands exhibited the highest SDRR values, early OA patients had slightly lower levels and late OA patients before TKR displayed significantly reduced SDRR (p>0.001). The same differences were observed in pRR50 and RMSSD. Serum cortisol concentrations and PSQ scores increased in late OA patients before TKR. At the time point of TKR, women with beta blocker medication had significantly higher age (71 ± 9 years) than those without (63 ± 12 years)(p>0.01). An autonomic dysfunction with sympathetic dominance occurs in OA patients. The fact that beta blocker medication in women delayed the need of TKR indicates that SNS inhibition might counteract OA. Future therapeutic interventions for OA should consider a systemic approach with special regard on the ANS

Background & Objectives. Sensory and motor manifestations in carpal tunnel syndrome (CTS) are well documented, whereas the associated autonomic dysfunction is often overlooked. The aim of this study is to demonstrate that autonomic dysfunction of the CTS hands can be quantified by measuring skin capacitance. Methods. Patients with clinical and electrophysiological signs of idiopathic carpal tunnel syndrome meeting the inclusion criteria were recruited. The patients were also scored based on the Brigham carpal tunnel severity score. Skin capacitance was measured using Corneometer CM825 (C&K Electronic, GmbH). The measurements were taken from the palmar aspect of distal phalanx of the index and little finger of the affected hand. Normal healthy patients with no signs and symptoms of carpal tunnel syndrome were recruited as controls and skin capacitance was measured in a similar fashion as the CTS group. Results. The CTS group consisted of 25 patients (18 female & 7 male) and 35 hands with an average age of 59.2 years (33-83 years). The mean symptom severity score was 2.80 (1.27-4.18; SD 0.82) and functional status score was 2.53 (1-4.26; SD 1.08). The mean ratio of skin hydration between the index and little finger was 0.85 (0.6-1.25; SD 0.155). Using the paired t-test to determine paired differences between index and little finger measurements, the mean difference was 12.6 (p<0.001). The control group consisted of 15 people (9 female and 6 male) and 30 hands. The average age was 47.3 years. The mean ratio of skin hydration between the index and little finger was 0.97 (0.77-1.42 SD 0.105). Using the paired t-test to determine paired differences between index and little finger measurements, the mean difference was 1.31 (p=0.317). The difference in skin hydration between the index and little finger was directly compared between the controls and CTS group, this difference was statistically significant, p=0.002. Conclusion. A simple method to determine dysautonomia, using Corneometer CM825, by the clinician has been demonstrated. Measurement of skin capacitance will reduce the dependence on electrophysiological studies, thus reducing the time for arriving at a diagnosis, improved patient satisfaction and cost-effectiveness