TY - JOUR
T1 - Motor adaptation varies between individuals in the transition to sustained pain
AU - Summers, Simon J.
AU - Chipchase, Lucy S.
AU - Hirata, Rogerio
AU - Graven-Nielsen, Thomas
AU - Cavaleri, Rocco
AU - Schabrun, Siobhan M.
PY - 2019
Y1 - 2019
N2 - Musculoskeletal pain is associated with altered motor control that, despite short-term benefit, is hypothesised to have long-term consequences, contributing to the development of chronic pain. However, data on how motor control is altered when pain is sustained beyond a transient event are scarce. Here, we investigated motor adaptation, and its relationship with corticomotor excitability, in the transition to sustained muscle pain. Twenty-eight healthy individuals were injected with nerve growth factor into the right extensor carpi radialis brevis muscle on days 0 and 2. Motor adaptation and corticomotor excitability were assessed on day 22, before injection on days 0 and 2, and again on days 4 and 14.Motor adaptation was quantified during a radial–ulnar movement as kinematic variability of wrist flexion–extension and pronation–supination, and as electromyographic (EMG) variability of extensor carpi radialis brevis activity. Pain, muscle soreness, and functional limitation were assessed from days 0 to 14. Pain, muscle soreness, and functional limitation were evident at days 2 and 4 (P < 0.001). Electromyographic variability reduced at days 4 and 14 (P < 0.04), with no change in kinematic variability (P = 0.9). However, data revealed variation in EMG and kinematic variability between individuals: some displayed increased motor variability, whereas others a decrease. Individuals who displayed an increase in EMG variability after 4 days of pain also displayed an increase in corticomotor excitability (r = 0.43, P = 0.034). These findings suggest individual adaptation of the motor system in the transition to sustained pain that could have implications for clinical musculoskeletal pain disorders.
AB - Musculoskeletal pain is associated with altered motor control that, despite short-term benefit, is hypothesised to have long-term consequences, contributing to the development of chronic pain. However, data on how motor control is altered when pain is sustained beyond a transient event are scarce. Here, we investigated motor adaptation, and its relationship with corticomotor excitability, in the transition to sustained muscle pain. Twenty-eight healthy individuals were injected with nerve growth factor into the right extensor carpi radialis brevis muscle on days 0 and 2. Motor adaptation and corticomotor excitability were assessed on day 22, before injection on days 0 and 2, and again on days 4 and 14.Motor adaptation was quantified during a radial–ulnar movement as kinematic variability of wrist flexion–extension and pronation–supination, and as electromyographic (EMG) variability of extensor carpi radialis brevis activity. Pain, muscle soreness, and functional limitation were assessed from days 0 to 14. Pain, muscle soreness, and functional limitation were evident at days 2 and 4 (P < 0.001). Electromyographic variability reduced at days 4 and 14 (P < 0.04), with no change in kinematic variability (P = 0.9). However, data revealed variation in EMG and kinematic variability between individuals: some displayed increased motor variability, whereas others a decrease. Individuals who displayed an increase in EMG variability after 4 days of pain also displayed an increase in corticomotor excitability (r = 0.43, P = 0.034). These findings suggest individual adaptation of the motor system in the transition to sustained pain that could have implications for clinical musculoskeletal pain disorders.
KW - muscles
KW - musculoskeletal system
KW - pain
KW - motor cortex
KW - motor ability
UR - http://hdl.handle.net/1959.7/uws:52815
U2 - 10.1097/j.pain.0000000000001604
DO - 10.1097/j.pain.0000000000001604
M3 - Article
SN - 1872-6623
SN - 0304-3959
VL - 160
SP - 2115
EP - 2125
JO - Pain
JF - Pain
IS - 9
ER -