Table 3

Comparison of the final values of SSR, PPT and NMJR between the two groups

VariablePatients (n=20)Healthy volunteers (n=20)TimeTime×group interaction
Pre-DN Post-DNPre-DN Post-DNFp ValueEffect sizeFp ValueEffect size
Ipsilateral SSR latency (s)1.15±0.381.34±0.291.11±0.281.35±0.48160.00010.30.20.70.005
Ipsilateral SSR amplitude (mV)2.5±1.41.3±1.01.4±0.71.4±1.17.30.010.26.90.010.15
Contralateral SSR latency (s)1.2±0.371.32±0.341.11±0.331.28±0.378.90.0050.20.30.60.008
Contralateral SSR amplitude (mV)2.0±1.41.2±1.31.2±1.11.5±1.60.50.50.14.20.040.1
PPT (kg/cm2)1.15±0.501.52±0.592.42±1.381.71±1.162.80.10.07280.00010.4
NMJR (%)5.6±26.7−2.9±13.8−0.9±10.90.9±6.8 
PI (NRS score)5 (4–7)2 (1–3.8)z=−3.9, p= 0.0001 
  • p value<0.05 is significant.

  • Data are presented as mean±SD or median (IQR).

  • DN, dry needling; NMJR, neuromuscular junction response; NRS, numerical rating scale; PI, pain intensity; PPT, pressure pain threshold; SSR, skin sympathetic response.