TY - JOUR
T1 - Reorganization of the primary motor cortex following lower-limb amputation for vascular disease
T2 - a pre-post-amputation comparison
AU - Hordacre, Brenton
AU - Bradnam, Lynley V.
AU - Crotty, Maria
PY - 2017
Y1 - 2017
N2 - Purpose: This study compared bilateral corticomotor and intracortical excitability of the primary motor cortex (M1), pre- and post-unilateral transtibial amputation.Method: Three males aged 45, 55, and 48 years respectively who were scheduled for elective amputation and thirteen (10 male, 3 female) healthy control participants aged 58.9 (SD 9.8) were recruited. Transcranial magnetic stimulation assessed corticomotor and intracortical excitability of M1 bilaterally. Neurophysiological assessments were performed 10 (SD 7) days prior to surgery and again at 10 (SD 3)days following surgery. Data were analyzed descriptively and objectively compared to 95% confidence intervals from control data.Results: Prior to amputation, all three patients demonstrated stronger short-latency intracortical inhibition evoked from M1 ipsilateral to the affected limb and reduced long-latency intracortical inhibition evoked from M1 contralateral to the affected limb compared to control subjects. Following amputation, short-latency intracortical inhibition was reduced in both M1s and long-latency intracortical inhibition was reduced for the ipsilateral M1. Single-pulse motor evoked potential amplitude and motor thresholds were similar pre-to-post amputation.Conclusions: Modulation of intracortical excitability shortly following amputation indicates that the cortical environment may be optimized for reorganization in the acute post-amputation period which might be significant for learning to support prosthetic mobility.
AB - Purpose: This study compared bilateral corticomotor and intracortical excitability of the primary motor cortex (M1), pre- and post-unilateral transtibial amputation.Method: Three males aged 45, 55, and 48 years respectively who were scheduled for elective amputation and thirteen (10 male, 3 female) healthy control participants aged 58.9 (SD 9.8) were recruited. Transcranial magnetic stimulation assessed corticomotor and intracortical excitability of M1 bilaterally. Neurophysiological assessments were performed 10 (SD 7) days prior to surgery and again at 10 (SD 3)days following surgery. Data were analyzed descriptively and objectively compared to 95% confidence intervals from control data.Results: Prior to amputation, all three patients demonstrated stronger short-latency intracortical inhibition evoked from M1 ipsilateral to the affected limb and reduced long-latency intracortical inhibition evoked from M1 contralateral to the affected limb compared to control subjects. Following amputation, short-latency intracortical inhibition was reduced in both M1s and long-latency intracortical inhibition was reduced for the ipsilateral M1. Single-pulse motor evoked potential amplitude and motor thresholds were similar pre-to-post amputation.Conclusions: Modulation of intracortical excitability shortly following amputation indicates that the cortical environment may be optimized for reorganization in the acute post-amputation period which might be significant for learning to support prosthetic mobility.
KW - Transcranial magnetic stimulation
KW - amputation
KW - motor reorganization
KW - motor cortex
KW - human
UR - http://www.scopus.com/inward/record.url?scp=85002199059&partnerID=8YFLogxK
U2 - 10.1080/09638288.2016.1207110
DO - 10.1080/09638288.2016.1207110
M3 - Article
SN - 0963-8288
VL - 39
SP - 1722
EP - 1728
JO - Disability and Rehabilitation
JF - Disability and Rehabilitation
IS - 17
ER -