Ghédira M1, Pradines M1, Mardale V1, Bayle N1, Gracies J-M1, Hutin E1
1Hôpitaux Universitaires Henri Mondor, Assistance Publique des Hôpitaux de Paris (AP-HP), Université Paris-Est Créteil (UPEC), Laboratoire Analyse et Restauration du Mouvement (ARM), EA 7377 BIOTN, Department of Rééducation Neurolocomotrice, Créteil, France
Background: Paresis in agonists, contracture and overactivity in antagonists impede ambulation in hemiparesis.
Purpose: The objective is to explore correlations between ambulation speed and coefficients of shortening, spasticity and weakness (involving paresis and cocontraction) in key lower limb extensors in chronic hemiparesis.
Methods: This retrospective study includes 140 subjects with chronic hemiparesis assessed during a single visit at least 3 months after botulinum toxin injection in lower limb using: 10-meter ambulation test at comfortable and fast speed to quantify ambulation speed and measurement of passive range of motion (XV1), angle of catch at fast stretch (XV3) and active range of motion (XA) against gastrocnemius (GN), rectus femoris (RF) and gluteus maximus (GM). Coefficients of shortening (CSHORT=[XN-XV1]/XN; XN, normal expected amplitude), spasticity (CSPAS=[XV1-XV3]/XV1) and weakness (CWEAK=[XV1-XA]/XV1) were derived. For each muscle, multivariable analysis explored CSHORT, CSPAS and CWEAK as potential predictors of ambulation speed.
Results: Mean ambulation speeds were 0.62±0.28m/s (comfortable) and 0.84±0.38m/s (fast). Speed correlated with CSHORT and CWEAK against GN (CSHORT, fast, β=-0.20, p=0.03; comfortable, ns; CWEAK, comfortable, β=-0.21, p=0.010; fast, β=-0.21, p=0.012), against RF (CSHORT, comfortable, β=-0.41, p=6E-7; fast, β=-0.43, p=5E-7; CWEAK, comfortable, β=-0.36, p=5E-5; fast, β=-0.33, p=0.0003) and against GM (CSHORT, comfortable, β=-0.19, p=0.02; fast, β=-0.26, p=0.002; CWEAK, comfortable, β=-0.26, p=0.002; fast, β=-0.22, p=0.010). Speed was not correlated with CSPAS.
Conclusion(s): In chronic hemiparesis, ambulation speed correlates with passive and active range of motion against lower limb extensors, not with their spasticity level. This may encourage therapists to primarily focus on treatment of muscle shortening by sustained stretching and of paresis/cocontraction by active training.
Implications: The main results of this study rule spasticity out preponderant mechanisms of ambulation degradation, against muscle contracture, paresis and spastic contraction, which are strongly associated with ambulation speed. These findings encourage therapists to orient the patient for techniques of muscle stretching coupled with increased active central control training to the agonist and reduced to the antagonist for improvement of ambulation in chronic hemiparesis.
Keywords: Paresis, Overactivity, Walking
Funding acknowledgements: The authors would like to thank the Association Neuroloco for a PhD degree scholarship.
Purpose: The objective is to explore correlations between ambulation speed and coefficients of shortening, spasticity and weakness (involving paresis and cocontraction) in key lower limb extensors in chronic hemiparesis.
Methods: This retrospective study includes 140 subjects with chronic hemiparesis assessed during a single visit at least 3 months after botulinum toxin injection in lower limb using: 10-meter ambulation test at comfortable and fast speed to quantify ambulation speed and measurement of passive range of motion (XV1), angle of catch at fast stretch (XV3) and active range of motion (XA) against gastrocnemius (GN), rectus femoris (RF) and gluteus maximus (GM). Coefficients of shortening (CSHORT=[XN-XV1]/XN; XN, normal expected amplitude), spasticity (CSPAS=[XV1-XV3]/XV1) and weakness (CWEAK=[XV1-XA]/XV1) were derived. For each muscle, multivariable analysis explored CSHORT, CSPAS and CWEAK as potential predictors of ambulation speed.
Results: Mean ambulation speeds were 0.62±0.28m/s (comfortable) and 0.84±0.38m/s (fast). Speed correlated with CSHORT and CWEAK against GN (CSHORT, fast, β=-0.20, p=0.03; comfortable, ns; CWEAK, comfortable, β=-0.21, p=0.010; fast, β=-0.21, p=0.012), against RF (CSHORT, comfortable, β=-0.41, p=6E-7; fast, β=-0.43, p=5E-7; CWEAK, comfortable, β=-0.36, p=5E-5; fast, β=-0.33, p=0.0003) and against GM (CSHORT, comfortable, β=-0.19, p=0.02; fast, β=-0.26, p=0.002; CWEAK, comfortable, β=-0.26, p=0.002; fast, β=-0.22, p=0.010). Speed was not correlated with CSPAS.
Conclusion(s): In chronic hemiparesis, ambulation speed correlates with passive and active range of motion against lower limb extensors, not with their spasticity level. This may encourage therapists to primarily focus on treatment of muscle shortening by sustained stretching and of paresis/cocontraction by active training.
Implications: The main results of this study rule spasticity out preponderant mechanisms of ambulation degradation, against muscle contracture, paresis and spastic contraction, which are strongly associated with ambulation speed. These findings encourage therapists to orient the patient for techniques of muscle stretching coupled with increased active central control training to the agonist and reduced to the antagonist for improvement of ambulation in chronic hemiparesis.
Keywords: Paresis, Overactivity, Walking
Funding acknowledgements: The authors would like to thank the Association Neuroloco for a PhD degree scholarship.
Topic: Neurology: stroke; Disability & rehabilitation; Human movement analysis
Ethics approval required: Yes
Institution: Henri Mondor Hospital
Ethics committee: ANSM
Ethics number: n° ID RCB: 2017-A00974-49
All authors, affiliations and abstracts have been published as submitted.
