The influence of experimental anterior knee pain during running on electromyography and articular cartilage metabolism  W.M. Denning, S. Woodland, J.G. Winward, M.G. Leavitt, A.C. Parcell, J.T. Hopkins, D. Francom, M.K. Seeley  Osteoarthritis and Cartilage  Volume 22, Issue 8, Pages 1111-1119 (August 2014) DOI: 10.1016/j.joca.2014.05.006 Copyright © 2014 Osteoarthritis Research Society International Terms and Conditions

Fig. 1 A description of the general timeline for each data collection session. EMG #1 and EMG #2 indicate the times, within the run, that EMG data were collected. Osteoarthritis and Cartilage 2014 22, 1111-1119DOI: (10.1016/j.joca.2014.05.006) Copyright © 2014 Osteoarthritis Research Society International Terms and Conditions

Fig. 2 The knee saline infusion set-up. A pocket (A) that was sewn into the front of a spandex shirt held the portable syringe pump and syringe. A connection tube (B) was used to connect the syringe and the catheter (C) that was inserted into the infrapatellar fat pad. Osteoarthritis and Cartilage 2014 22, 1111-1119DOI: (10.1016/j.joca.2014.05.006) Copyright © 2014 Osteoarthritis Research Society International Terms and Conditions

Fig. 3 Means and 95% CIs for subject-perceived pain across time for each data collection session (95% CIs are not included for the control session because they equaled zero at each time point). Subject-perceived pain significantly increased across time during the pain session only (P < 0.01). Asterisks show statistically significant differences when the pain session was compared to the sham and control sessions. Osteoarthritis and Cartilage 2014 22, 1111-1119DOI: (10.1016/j.joca.2014.05.006) Copyright © 2014 Osteoarthritis Research Society International Terms and Conditions

Fig. 4 Grand ensembles (99% CIs are only shown for involved (right) leg to increase clarity) for GA EMG amplitude (Amp), for the pain (A), control (B), and sham (C) sessions. D–F show results of bilateral functional comparisons, where mean bilateral differences and corresponding 99% CIs are plotted as a function of time. When the shaded area does not overlap with the zero line, a bilateral difference (P < 0.01) is indicated. Positive differences indicate that involved-leg (right) EMG is greater, while negative differences indicate the opposite. Osteoarthritis and Cartilage 2014 22, 1111-1119DOI: (10.1016/j.joca.2014.05.006) Copyright © 2014 Osteoarthritis Research Society International Terms and Conditions

Fig. 5 Grand ensembles (99% CIs are only shown for involved (right) leg to increase clarity) for VM EMG amplitude (Amp), for the pain (A), control (B), and sham (C) sessions. D–F show results of bilateral functional comparisons, where mean bilateral differences and corresponding 99% CIs are plotted as a function of time. When the shaded area does not overlap with the zero line, a bilateral difference (P < 0.01) is indicated. Positive differences indicate that involved-leg (right) EMG is greater, while negative differences indicate the opposite. Osteoarthritis and Cartilage 2014 22, 1111-1119DOI: (10.1016/j.joca.2014.05.006) Copyright © 2014 Osteoarthritis Research Society International Terms and Conditions

Fig. 6 Grand ensembles (99% CIs are only shown for involved (right) leg to increase clarity) for VL EMG amplitude (Amp), for the pain (A), control (B), and sham (C) sessions. D–F show results of bilateral functional comparisons, where mean bilateral differences and corresponding 99% CIs are plotted as a function of time. When the shaded area does not overlap with the zero line, a bilateral difference (P < 0.01) is indicated. Positive differences indicate that involved-leg (right) EMG is greater, while negative differences indicate the opposite. Osteoarthritis and Cartilage 2014 22, 1111-1119DOI: (10.1016/j.joca.2014.05.006) Copyright © 2014 Osteoarthritis Research Society International Terms and Conditions

Fig. 7 Means and 95% CIs for serum COMP concentration at three times for each session. If pooled from each session, serum COMP concentration was significantly greater immediately post-run, relative to pre-run and 60 min post-run; this trend was consistent between sessions. Osteoarthritis and Cartilage 2014 22, 1111-1119DOI: (10.1016/j.joca.2014.05.006) Copyright © 2014 Osteoarthritis Research Society International Terms and Conditions